description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF THE INVENTION
1. Field of the Invention
Filtering and particulate washing device.
2. Background of the Invention
The rapid and efficient filtering of a number of different liquids and the washing of the particulates resulting therefrom has in the past required excessive time in laboratories.
A major object of the present invention is to provide a device to selectively carry out the filtering of a number of liquids, either concurrently or individually, and to wash the particulates resulting therefrom with a desired liquid prior to the particulates being removed from the invention.
Another object of the invention is to supply a multiple filtering and particulate washing device that has a simple mechanical structure, is simple and easy to use, requires a minimum of maintenance attention, and one that will substantially reduce laboratory time required in filtering and particulate washing operations.
SUMMARY OF THE INVENTION
The present invention is used in conjunction with a vacuum creating source and a source of a pressurized first liquid to selectively filter one or more desired second liquids either concurrently or in sequence, and to wash the particulates resulting therefrom with the first liquid prior to the particulates being removed from the invention.
Each of the devices includes a number of assembliesfor holding individually a number of second liquids prior to the latter being subjected to a filtering operation. Each of the assemblies includes an elongate vertically positionable cylinder having an upper end and a lower end. Each cylinder is provided with a cover that engages the upper end, with the cover having first, second and third spaced openings therein. The first openings serve to introduce one of the second liquids into the cylinder prior to the filtering operation. A stopper is provided that removably engages the first opening.
A number of lengths of pliable tubing are provided, each of which lengths is in communication with one of the second openings. A number of rotatable first valve means are provided, each of which is removably secured to the lower end of one of the cylinders. Each of the valve means has a longitudinal passage therein, and each first valve means further including a lower end portion on which external threads are defined. Each first valve means includes a resilient seal supported thereon and situated below the external threads previously mentioned. Each of the first valve means includes a filter so disposed therein that second liquid in the cylinder must pass through the filter prior to flowing from the first valve means.
Each of the devices includes an elongate rigid manifold block that has a flat lower surface, a top, first and second end walls and a pair of first and second side walls, and first and second passages that extend longitudinally through the manifold block to terminate at the first and second end walls.
A number of longitudinally spaced first bores extend downwardly in the manifold box from the top thereof to the first passage. Each of the first bores includes a tapped portion and a circular body shoulder situated therebelow. Each of the previously mentioned tapped portions of the first bores is rotatably engaged by one of the threaded portions of one of the first valve means. The manifold block also has a number of longitudinally spaced second bores therein that extend inwardly from the first side wall to the second passage.
A number of second valve means are provided that are connected to the second bores, as well as to the pliable hose, with each of the second valve means capable of occupying either first or second positions in which communication is blocked or effected between the pliable hose and the second passage. A pair of plugs are provided for sealing the first and second passages at the first end wall of the manifold block. A first conduit is provided that connects the vacuum creating source to the first passage at the second end wall, and a second conduit serves to likewise connect the source of pressurized first liquid to the second passage at the second end wall. Each of the third openings in the cover has a vent assembly therein, which vent assembly includes a porous member that prevents air-borne material entering the cylinder with which the vent assembly is associated, but allows air to escape from the cylinder when the first liquid is being discharged therein to wash particulate on the filter associated with that cylinder.
The use and operation of the invention is as follows.
The second valve means are placed in the first position to obstruct communication between the second passage and the interior of the cylinders. Each second liquid to be filtered is introduced into a cylinder through the first opening in the cover thereof. During introduction of a second fluid into one of the cylinders, the first valve means is disposed in a second position in which communication between the interior of the cylinders and the first passage is blocked. A number of the second liquids may be concurrently filtered, by moving the first valve means of the cylinders in which they are diposed to second positions where communication is established between the interior of the cylinder and the first passage. The vacuum in the first passage causes second liquids in the cylinder to flow downwardly through the filters, with their particulate being deposited thereon. After all of the second liquids have been drawn into the first passage to flow to the vacuum creating means, the second valve means are placed in second positions for first liquids to flow under pressure from the second passage and the pliable hose into the cylinders to wash the particulates that have been deposited on the filters therein. The first liquid after the washing particulates is drawn downwardly through the filters into the first passage to be discharged therefrom. The filters bearing the particulates are now separated from the portion of the first valve means that held the filters, and also held the cylinders in fixed relationship therewith.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of the device and the vacuum creating source and source of pressurized first liquid being illustrated diagrammatically;
FIG. 2 is a combined side elevational and vertical cross sectional view of the device illustrated in FIG. 1;
FIG. 3 is a fragmentary vertical cross-sectional view of the device with both the first and second valve means illustrated in the closed position;
FIG. 4 is the same view as shown in FIG. 3 but with both the first and second valve means illustrated in open positions;
FIG. 5 is an end view of the device;
FIG. 6 is a longitudinal cross sectional view of a first manifold block illustrating the manner in which the second passage therein may be removably connected to a second passage of the manifold block;
FIG. 7 is a top plan view of one of the covers that is removably mounted on one of the cylinders;
FIG. 8 is a fragmentary longitudinal cross-sectional view of the upper portion of one of the second liquid holding container assemblies;
FIG. 9 is a fragmentary side elevational view of two of the filtering devices disposed end-to-end and the first passages therein removably connected by a conduit assembly; and
FIG. 10 is a fragmentary longitudinal cross sectional view of the upper portion of one of the second liquid holding container assemblies and illustrating a quick release connector that establishes communication between one of the resilient tubes and the interior of the container assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The filtering and particulate washing invention A is illustrated in FIG. 1 in association with a vacuum creating source B and source C of pressurized first liquid D. The device A is used to separate particulates 10 from a number of separate second liquids E, and wash the particulates so separated with the first liquid D prior to the particulates being removed. The vacuum creating source B and source C of pressurized first liquid D are shown diagrammatically in FIG. 1.
The invention A includes a number of assemblies F that are shown in FIGS. 1 to 4 inclusive. Each assembly F includes an elongate, rigid, transparent, vertically disposed cylinder 12 that has an upper end 14 and lower end 16. Each cylinder 12 has an upper section 12a and a lower section 12b of lesser diameter. The sections 12a and 12b at their junction define a circumferentially extending groove 13 in which a resilient sealing ring 15 is disposed.
Each cylinder 12 is provided with a cover G as shown in FIGS. 1 and 8. In FIG. 8 it will be seen that each cover G includes a cylindrical body 17 from which a circular flange 19 projects outwardly from the upper portion thereof. Body 17 has a circumferential groove 17a therein in which a resilient sealing ring 21 is disposed. The sealing ring 21 is in pressure sealing contact with a recessed interior circular side wall portion of the upper cylinder section 12a when body 17 of cover G is pressed downwardly therein as shown in FIG. 8. Each cover G has first, second and third spaced openings 18, 20 and 22 extending downwardly therethrough. The first opening 18 in each cover G has a stopper H removably and sealingly mounted therein. Each second opening 20 is, by a quick release fitting 2, connected to a length of pliable tubing J as shown in FIG. 1.
Each cylinder 12 has the lower section 12a removably engaged by a first valve assembly K shown in detail in FIGS. 3 and 4. Each valve assembly K includes a threaded section 24 and a resilient seal 26 situated therebelow. The valve assemblies K serve to hold the cylinder assemblies F in vertical positions above a manifold block L shown in FIGS. 1, 3 and 4.
The manifold block L is formed from a rigid material and has a flat lower surface 28, top 30, first and second end walls 32, 34, and first and second side walls 36 and 38. Manifold block L has first and second laterally spaced passages 40 and 42 that extend longitudinally between the first and second end walls 32 and 34. A number of longitudinally spaced first bores 44 of circular transverse cross-section extend downwardly in block L from the top 30 thereof and are in communication with first passage 40.
Each of the first bores 44 includes an internally threaded portion 46 and a circular body shoulder 48 therebelow. A number of longitudinally spaced second bores 50 are formed in manifold block L and extend inwardly from second side wall 38 to communicate with second passage 42. Each of the second bores 50 has a second valve assembly M mounted therein and extending outwardly from manifold block L as shown in FIGS. 3 and 4. The entrance to first and second passages 40 and 42 at first end wall 32 are removably sealed by plugs N. First passage 40 at the second end wall 34 has a tubular fitting O sealingly mounted therein and the second passage 42 likewise has a tubular fitting P in engagement therewith.
Each cover G as may be seen in FIG. 8 has an air vent assembly Q mounted in the third opening 22 thereof. Each third opening 22 has a circular body shoulder 22a defined therein. A screen 52 rests on body shoulder 22a and spans the third opening 22. A porous sheet 54 is supported on screen 52. The outer peripheral portion of screen 52 has a resilient sealing ring 56 resting thereon, and the sealing ring being held in place by a tubular member 58 that frictionally engages the third opening 22.
The first valve assemblies K not only serve to support the cylinders 12 in upwardly extending positions relative to manifold block L, but also provide supports for filter assemblies R as may be seen in FIGS. 3 and 4. Each of the filter assemblies R includes a circular, rigid, apertured plate 60, preferably formed from stainless steel, a screen 62 of larger diameter that rests on plate 60, and a circular filter media 64 of the same diameter as the screen and is supported on the upper surface thereof as shown in FIGS. 3 and 4.
Each first valve assembly K includes a rigid vertically disposed tubular shell 66 that slidably and snugly receives the lower cylinder section 12b within the interior thereof. Shell 66 has an upper interior grooved portion 68 that is removably and sealingly engaged by resilient ring 15. Shell 66 defines a circular interior body shoulder 70 from which a threaded interior circular surface 72 of the shell extends downwardly as shown in FIGS. 3 and 4.
Body shoulder 70 has a resilient sealing ring 74 in abutting contact therewith. Sealing ring 74 is also in abutting contact with the outer peripheral edge portion of filter media 64. A rigid circular body 76 is provided that has a tubular neck 78 depending therefrom, with the bore 80 in neck 78 developing into a tapered surface 82 in the body 76. The tapered surface 82 on the upper edge develops into a flat ring-shaped surface 84 on which the apertured plate 60 rests. Ring-shaped surface 84 is surrouned by a circular rib 86 that forms a part of body 76, with the rib having a flat upper surface on which the outer peripheral portion of screen 62 rests. The rib 86 and a portion of body 76 therebelow have threads 88 formed on the interior surface thereof that engage threads 72 of shell 66. When shell 66 is rotated in an appropriate direction relative to body 76 it moves downwardly relative to the latter due to engagement of threads 72 and 80, and resilient ring 74 effects a pressure seal between body shoulder 70 and filter media 64.
Valve assembly K also includes a valve member 90 that includes an upper portion 92 from which an elongate lower portion 94 of smaller diameter depends, with lower portion having a threaded section 24 defined thereon. The lower extremity of lower portion 94 supports resilient seal 26 as shown in FIGS. 3 and 4. Lower portion 94 adjacent the upper portion 92 of valve member 90 has a circumferential groove 96 therein in which a resilient seal ring 98 is disposed that is at all times in pressure sealing contact with the upper poart of bore 44.
The neck 78 as may be seen in FIGS. 3 and 4 has a circumferentially extending groove 100 on the external surface thereof in which a resilient sealing ring 102 is disposed. The neck 78 and sealing ring may be slid downwardly in a cavity 104 defined in valve member 90. Cavity 104 is in communication with a bore 106 that extends downwardly in lower portion 94 to terminate in a number of transverse bores 108.
When valve body 90, shell 66, and cylinder 12 associated therewith are concurrently rotated in an appropriate direction relative to manifold block L, the threads 24 and 46 rotate relative to one another and move seal 26 into pressure sealing contact with body shoulder 48. When such a seal is effected, second liquid E in cylinder 12 cannot be drawn downwardly through filter assembly R, even though a vacuum exists in first passage 40. Valve assembly K is shown in a sealing position in FIG. 3. In FIG. 4 the valveassembly K is shown in a position where a vacuum in first passage 40 will cause second liquid E in cylinder 12 to be drawn downwardly through filter assembly R, bore 106 and transverse bores 108 into first passage 40, with particulates 10 in the second liquid being retained on filter media 64.
The flow of first liquid D to wash the particulates is controlled by the second valve assemblies M. Each valve assembly M includes a valve body 110 that includes a cylindrical shell 112 having a tubular plug 114 extending longitudinally therefrom, which plug has external threads 116 thereon that engage threads 50a defined in one of the second bores 50. Shell 112 has intermediately disposed threads 118 on the interior surface thereof, and the shell and tubular plug 114 at their junction defining an interior ring-shaped body shoulder 120.
Threads 116 are in engagement with threads 122 on an elongate valve member 124, which valve member on the lower extremity supports a resilient seal 126 that may be brought into pressure sealing contact with body shoulder 120 as shown in FIG. 3. The portion of valve member 124 supporting seal 126 is of smaller transverse area than that of the interior portion of the shell 112 in which it is disposed. Valve member 124 has a circumferential groove 128 therein above threads 122, which groove has a resilient sealing ring 130 mounted therein that is at all times in sealing engagement with a smooth interior cylindrical surface 132 in valve body shell 112.
Valve member 124 includes an externally knurled cylindrical handle 134 outwardly disposed from the shell 112 as best seen in FIG. 3. An externally barbed tubular nipple 136 extends outwardly from handle 134 and is longitudinally aligned with the latter. The nipple 136 has one of the pliable tubes J removably secured thereto. A longitudinal bore 138 is defined in valve member 124 that communicates with nipple 136, and the bore developing into a number of transverse bores 139 adjacent the seal 126.
When the handle 134 is rotated in an appropriate direction the valve member 124 moves from the first position shown in FIG. 4 to the second position illustrated in FIG. 3 where seal 126 is in pressure contact with body shoulder 120 that serves as a valve seat. When seal 126 is so disposed communication between second passage 40 and bore 138 in valve member 124 is obstructed. By rotating the valve member 124 in the opposite direction the valve member may be moved to the first position illustrated in FIG. 4. Pressurized liquid F may now flow from second passage 42, tubular plug 114, and around seal 126 and through transverse bores 139 as indicated by arrow in FIG. 4 into bore 138 and then through pliable tube J into cylinder 12 to wash the particulates 10 on filter media 64. The shell 112 of valve body 110 at the junction with tubular plug 114 has a resilient seal ring 140 mounted thereon that is in sealing contact with second side wall 38 as shown in FIGS. 3 and 4.
The use of the invention A in filtering a number of different second liquids E and recovering the particulates 10 therefrom after the latter have been washed with the first liquid D is as follows.
The valve bodies 90 are rotated to move the seals 26 from the first position shown in FIG. 4 to the secondposition illustrated in FIG. 3 where the seals are in pressure contact with body shoulders 48 that serve as valve seats. Valve members 124 are likewise rotated to move seals 126 from the first position shown in FIG. 4 to the second position illustrated in FIG. 3. Each of the second liquids is now introduced into one of the cylinders 12. The valve bodies 90 shown in FIGS. 3 and 4 are rotated to dispose the seals in the second position in FIG. 3. The vacuum in first passage 40 causes the second liquid E to be drawn downwardly through filter assemblies R into bores 106 to flow through transverse bores 108, and thereafter flow around seals 26 to discharge into first passage 40. The particulates 10 from the second liquids E are deposited on the filter media 64.
The valve members 124 are now rotated to move seals 126 from the second positions shown in FIG. 3 to the first positions illustrated in FIG. 4. Pressurized first liquid D now flows from second passage 42 through second valve assemblies M, tubes J into cylinders 12 to flow over particulates 10 on filter media 64 to wash the particulates. The first liquid D is drawn downwardly through the first valve assemblies K into first passage 40 due to the vacuum in the latter.
After the particulates 10 have been washed, the first and second valve assemblies K and M are moved to the second positions shown in FIG. 3. Each of the cylinders 12 with the associated shell 66 and body 76 may now be lifted upwardly to separate neck 78 from valve body 90. The shells 66 are now unscrewed from the bodies 76 and the filter media 64 with washed particulates 10 thereon obtained for subsequent laboratory procedures.
The separation of the cylinders 12 with the associated shells 66 and bodies 76 from valve members 90 as above described results in there being a temporary negative air pressure in the cylinders 12 prior to the necks 78 separating from the valve members 90. This negative pressure is prevented from forming in the invention A by each first cavity 104 having a transverse bore 142 extending therefrom to a cylindrical recess 144. A tubular member 146 is pressed into the recess 144 and abuts against a sealing ring 148 that is in contact with a porous transverse sheet 150. Sheet 150 presses against a screen 152 that is in contact with a portion of the bottom 144a of recess 144. Bore 142 is disposed above sealing ring 102 on neck 78 as may be seen in FIG. 4.
Due to the above-described structure when neck 78 is moved upwardly in first cavity 104 above bore 142, air from the ambient atmosphere may flow through tubular member 146, filter sheet 150 and screen 152 into the interior of body 76. Thus, there is no differential in pressure between the interior of cylinder 12 and the ambient atmosphere that would cause a rush of air onto the filter media 64 to disturb particulates 10 thereon or contaminate the same with air borne material. Air borne material is removed by the porous sheet 150, which may be filter paper, as air flows from the ambient atmosphere into the interior of each body 76.
The vacuum creating source B and source C of first pressurized liquid D are conventional and are shown diagrammatically in FIG. 1. The first passage 40 as shown in FIG. 2 has enlarged cylindrical end portions 40a. The fitting O that engages the end portion 40a adjacent second end wall 34 as shown in FIG. 2 includes a knurled cylindrical handle 154 that has an externally barbed tubular member 156 projecting from a first side and a cylindrical member 158 from the opposite side. A bore 160 extends longitudinally through tubular member 156, handle 154 and cylindrical member 158. Cylindrical member 158 has two longitudinally spaced circumferentially extending grooves 162 therein in which resilient sealing rings 164 are disposed. The barbed tubular member 156 is engaged by a pliable tube 166 that extends to a tubular connection 168 that extends through the top 170 of a cylindrical trap 172. A second tubular connection 174 extends through top 170, with the second connection being in communication with a tube 176 that extends to the suction side of a vacuum pump 178 that is driven by a prime mover 180, an electric motor, or the like.
When a single invention A is being used as shown in FIG. 1, the passage portion 40a adjacent the first end wall 32 is removably engaged by a sealing plug N. The plug N includes a rigid cylindrical body 182 that has a knurled cylindrical handle 184 on one end thereof. Body 182 has two longitudinally spaced, circumferentially extending grooves 186 therein in which resilient sealing rings 188 are supported. The plug N when pressed into passage portion 40a seals one end of first passage 40 from communication with the ambient atmosphere.
The second passage 42 as may be seen in FIG. 6 has tapped end portions 42a. The fitting P that engages the end portion 42a adjacent second end wall 34 is similar to fitting O and differs from the latter only in that the handle 189 has a number of flat wrench engageable faces defined thereon and the portion (not shown) that extends into the end portion 42a is externally threaded.
The fitting P is connected to a tube 190 that extends downwardly through a top 192 of a pressure vessel 194 to terminate adjacent the bottom 196 thereof. A tube 198 is connected to a cylinder 200 containing a pressurized inert gas such as nitrogen, which tube extends through the top 192 to communicate with the interior of the pressure vessel. The pressure vessel contains a quantity of the first liquid D. By opening a valve 202 on cylinder 200 pressurized gas flows to the interior of vessel 194 and first liquid D under pressure flows to second passage 42 for subsequent washing of the particulates 10 as previously described.
When it is desired to concurrently filter more second liquids E than may be handled by a single invention A as shown in FIG. 1, one of the inventions A and an identical invention A' may be disposed end-to-end as shown in FIG. 9. A connector 204 is now used to establish communication between the first passages 40 and 40' as shown in FIG. 9. The connector 204 includes a knurled handle 206 that has first and second cylindrical bodies 208 and 210 that extend outwardly from opposite ends thereof. The bodies 208 and 210 have two longitudinally spaced circumferentially extending grooves 212 thereon in which resilient sealing rings 214 are disposed. A bore 216 extends longitudinally through connector 204. The connector 204 removably and sealingly engages the adjacent end portions 40a and 40a' of the two aligned first passages 16 and 16'. Thus, when a vacuum is established in first passage 40 it will also be effected in first passage 40'. By the above-described means any number of longitudinally aligned manifold blocks L may have the first passages 40 therein removably and sealingly connected to one another.
The second passages 42 and 42' in manifold blocks L and L' are connected by a connector 218 shown in FIG. 6 which includes a tube 220 that has two longitudinally spaced, externally threaded tubular members 222 rotatably and sealingly mounted thereon that engage end portions 42a and 42a' of the second passages 42 and 42'. Thus when pressurized second liquid E is supplied to second passage 42 for particulate 10 washing purposes it is also supplied to second passage 42' in manifold block L'.
The manifold block L preferably has spaced recesses 26 extending upwardly from the bottom 28 thereof that frictionally receive resilient supporting pads 228.
The quick release fitting Z as may be seen in FIG. 10 includes a ring-shaped intermediate member 300 that has a circumferential groove 302 in the exterior surface thereof that is occupied by an outwardly projecting resilient O-ring 304. An externally barbed first tubular member 306 extends from a first side of member 300 and frictionally and sealingly engages an interior end portion of one of the resilient tubes J. A smooth surfaced second tubular member 308 projects from a second side of intermediate member 300 as shown in FIG. 10. Second opening 20 in cover G has an intermediately disposed inwardly extending lip 20a. Second tubular member 308 has a slightly tapered external end portion 308a. When second tubular member 308 is extended downwardly through opening 20 the intermediate member 300 is disposed therein to the extent that O-ring 304 is in pressure contact with the upper portion of second opening 20 and effects a fluid tight seal therewith, with the intermediate member 30 being in abutting contact with the lip 20a.
The use and operation of the invention has been described previously in detail and need not be repeated. | A device which in combination with a vacuum creating source and a pressurized source of a first liquid, permits all or a portion of a number of second liquids to be selectively filtered either singly or concurrently, and the particulates resulting from the filtering operation washed separately with the first liquid prior to the particulates being removed from the device. The device is of such structure that a number thereof may be connected by tubular means end-to-end to permit the separate filtering of any desired number of second liquids and the subsequent washing of the particulates from the second liquids with a first liquid from a pressurized source thereof. | 1 |
This application is a continuation of application Ser. No. 07/826,075, filed on Jan. 27, 1992, abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for depositing an oxide film on the surface of a wafer.
Conventionally, an oxygen ion or gas atmosphere has been used when depositing an oxide film on a wafer by reactive ion-beam sputtering. However, if oxygen gas is used, the merging of sputtered particles is insufficient to achieve the desired film formation. On the other hand, the presence of oxygen ions can potentially cause damage to the deposited film. In addition, the films produced by these conventional techniques have an undesirably low crystallinity since the film is formed with sputtered particles which react with an oxygen ion in flight to form an oxide which builds up between the wafer and the deposited material. Further, the use of an oxygen atmosphere causes the reaction to be carried out at high temperatures resulting in various problems.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a method and apparatus for depositing an oxide film which overcomes the disadvantages of the prior art.
Another object of the invention is to provide a method and apparatus adapted to deposit oxide films of high quality at low temperature.
These and other objects of the invention are attained by depositing an oxide film by ion-beam sputtering of particles from a target toward the surface of a wafer and applying ozone to the particles that have been sputtered from the target in a region close to the surface of the wafer.
A film-depositing apparatus according to the invention includes a target, an ion beam source that emits an ion beam toward the target, a support for a wafer disposed in a position to receive particles sputtered from the target, and an ozone supply for providing ozone in a region near the surface of a wafer supported in the wafer support.
In accordance with the present invention, ozone provided in a region near the surface of the wafer is sufficiently active by itself to react with sputtered particles at a low temperature. In addition, the reaction of the ozone is promoted when the ozone receives heat from the wafer in the region adjacent to the wafer. Consequently, the mechanism of epitaxial growth can be used with the invention to form highly crystalline films.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and advantages of the invention will be apparent from a reading of the following description in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic diagram showing a representative method for depositing an oxide film according to a preferred embodiment of the present invention; and
FIGS. 2(a) and 2(b) are schematic illustrations showing oxide films deposited on wafers in accordance with the invention.
DESCRIPTION OF PREFERRED EMBODIMENT
In the representative method for depositing an oxide film in accordance with the present invention as shown in FIG. 1, an ion beam source 1 emits an ion beam 2 toward a target 3. Typical target materials are Si, SiO 2 and PZT (lead titanate zirconate). When the emitted ion beam 2 impacts the target 3, sputtered particles of the target material 4 are ejected in a given direction.
A wafer 5 is mounted in a position to receive the sputtered particles 4. The wafer 5 is typically heated from the back with a back-heating apparatus (not shown). In accordance with the invention, an ozone supply device 6 supplies ozone (O 3 ) so that it flows onto the surface of the wafer 5. An ozonizer is typically used as the ozone supply device.
In the film-depositing apparatus according to the illustrated embodiment, the surface of the wafer 5 is blanketed with an ozone layer. Since the ozone becomes active in response to the relatively low heat which it receives from the wafer 5, it will react readily with the sputtered particles 4 as they approach the wafer 5 so as to be deposited as an oxide on the wafer surface.
If PZT is used as the target 3, Pb is present in the sputtered particles 4. Since Pb has a low vapor pressure, it tends to vaporize from the wafer 5 once it has been deposited. To compensate for this, 10-20% more PbO is conventionally added to the target. However, if active ozone is present in the atmosphere near the wafer surface, as in the illustrated embodiment, the Pb in flight will readily react with ozone to form PbO so that the vaporization of Pb from the surface can be prevented. An obvious advantage of this phenomenon is that an oxide of a desired compositional ratio (Pb ratio) can be formed on the wafer even if the target is PZT and therefore there is no need to add an excess amount of PbO or other supplementary compounds to the target as in the prior art.
It is not essential that the ozone be heated by heat from the wafer 5. However, in the illustrated embodiment, where ozone is heated from the wafer 5 so as to react with sputtered particles 4, epitaxial growth will take place in response to the heat received from the back of the wafer so that an oxide film of very high crystallinity can be obtained. This will provide a benefit in the case where a semiconductor device of the type shown in FIG. 2(a), having a surface 9 which is uneven because of the presence of wiring 7, must be provided with a protective film 8. By using the present invention, an oxide film 8 can be formed which has good coverage and uniform thickness to fill any recesses and cover any ridges as shown in FIG. 2(a). In contrast, FIG. 2(b) shows a protective film 8 that has been formed without using the method of the invention. Consequently, the deposited film has poor coverage and nonuniform thickness.
As described above, the present invention utilizes a very simple construction and yet it is capable of forming an oxide film of high crystallinity and good coverage at low temperature. As a further advantage, a film of desired com positional ratio can be obtained with a multi-element target such as PZT since the constituent particles for the film will rapidly undergo an oxidation reaction. Therefore, the present invention will find great industrial utility.
Although the invention has been described herein with reference to a specific embodiment, many modifications and variations therein will readily occur to those skilled in the art. Accordingly, all such variations and modifications are included within the intended scope of the invention. | The specification discloses a method and apparatus for depositing an oxide film by ion-beam sputtering in which an oxide film is formed on the surface of a wafer by sputtering particles from a target toward the wafer and supplying ozone adjacent to the wafer to oxidize the particles that are close to the surface of the wafer. | 2 |
FIELD OF THE INVENTION
[0001] The invention relates to a pulley for drive system of an internal combustion engine. More particularly, the invention relates to pulley having a shape that counteracts and substantially reduces mechanical vibrations, in particular but exclusively in internal combustion engines.
DESCRIPTION OF THE RELATED ART
[0002] The serpentine accessory belt of the internal combustion engine drives devices like an alternator, an air conditioning compressor, a water pump, and a power steering pump. The energy is provided by the engine's crankshaft and is transmitted to driven components via a poly-V belt. This power delivery is not smooth. It occurs with the speed fluctuating intensely particularly at low rpm. Crankshaft torsionals are caused by the cycles of the internal combustion engine (intake, compression, combustion and exhaust). Particularly, the combustion cycle affects the amplitude of crankshaft torsionals.
[0003] When the frequency of these vibrations is close to the natural frequency of the drive, system resonance occurs. At resonance, the torsional vibrations and the span tension fluctuations are at their maximum. Tension fluctuations at resonance can easily cause the belt to slip on the crankshaft pulley or on the other pulleys depending on the magnitude of tension fluctuations, wrap angle, friction factor, etc. The belt slip is undesired because it disrupts power transmission, produces noise and reduces belt life. Vibrations may also cause wear of other components and result in other undesirable effects.
[0004] A novel approach to attenuating vibrations in internal combustion engines has been proposed in WO 03/046413. In this commonly assigned patent publication, it is proposed that a synchronous drive system in an engine be provided with a pulley or sprocket that has a non-circular profile. The non-circular profile produces an opposing fluctuating corrective torque. The angular position of the non-circular profile coincides with an angular position for which a maximum elongation of the drive span coincides with a peak value of the fluctuating load torque of the rotary load.
[0005] In the prior publication, the non-circular pulley or drive sprocket is fixed. However in many engines, as the RPM increases, the engine usually has smaller fluctuations in load torque. Thus, the need to introduce a counteracting torque as provided by the non-circular profile also diminishes. With a fixed profile, the counteracting torques will nonetheless be introduced into the drive system.
SUMMARY OF THE INVENTION
[0006] It is desirable to provide a rotor or pulley for a drive apparatus, wherein the rotor or pulley has a non-circular profile and an indicia marking enabling the pulley to be installed on a crankshaft in a desired orientation.
[0007] It is desirable to provide a rotor or pulley for a drive apparatus, wherein the rotor or pulley is able to alter its profile between a non-circular profile and a circular profile, so that the rotor can be dynamically altered depending on engine conditions.
[0008] According to one aspect of the invention, there is provided a pulley having a hub configured to be mountable on a driving shaft and a rim. There is a driving connection between the hub and rim. A drive assembly is operable to configure the rim between a circular profile and a non-circular profile. The drive assembly can be electrical, inertial, hydraulic or any combination thereof.
[0009] According to another aspect of the invention, there is provided a method for operating an engine. The engine has an endless drive system including a configurable crankshaft pulley. The method includes the steps of sensing engine conditions, such as RPM, accessory drive belt tension, to determine whether torque loads in the endless drive are in excess or about to be in excess of a predetermined value and responsively altering the profile of the crankshaft pulley between a circular and a noncircular profile to generate a counteracting torque in the belt.
[0010] According to another aspect of the invention, there is provided a pulley having a hub and a rim. The hub is configured to be mounted on a driving shaft, such as a crankshaft. The rim has a non-circular profile. The pulley has indicia thereon for orienting the pulley in a predetermined position relative to the driving shaft.
[0011] According to another aspect of the invention, there is provided a pulley having a hub and a rim. The hub is configured to be mountable on a driving shaft. The rim has a non- circular profile. The hub has means for orienting the hub in a predetermined position relative to the driving shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Advantages of the invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
[0013] FIG. 1 is a schematic view of a front of a vehicle engine with an endless belt extending through a serpentine path around a plurality of conventional pulleys and a pulley of the present invention;
[0014] FIG. 2 is a partial perspective view of an engine incorporating a pulley of the present invention;
[0015] FIG. 3 is a graph illustrating the relationship between torsional vibrations of a typical four cylinder engine resulting from an air conditioner compressor and an alternator;
[0016] FIG. 4 is perspective view of a first embodiment of a pulley of the present invention;
[0017] FIG. 5 is a partial elevational view of the pulley of FIG. 4 ;
[0018] FIG. 6 is schematic view of an endless drive system similar to FIG. 1 but having a different arrangement of pulley elements;
[0019] FIG. 7 is a plan view of a second embodiment of the present invention, with the inertia elements in the non-circular profile position;
[0020] FIG. 8 is a plan view of the embodiment of FIG. 7 , with the inertia elements in the circular profile position;
[0021] FIG. 9 is a partial sectional view of the embodiment of FIG. 7 , with the inertial element in the circular profile position;
[0022] FIG. 10 is a partial sectional view of the embodiment of FIG. 7 , with the inertial element in the non-circular profile position;
[0023] FIG. 11 is perspective view of a third embodiment of the present invention;
[0024] FIG. 12 is a partial plan view of the embodiment of FIG. 11 ;
[0025] FIG. 13 is a perspective view, partially in sectional, of fourth embodiment of the present invention;
[0026] FIG. 14 is sectional view of the embodiment of FIG. 13 ; and
[0027] FIG. 15 is a perspective view of a fifth embodiment of the pulley or rotor of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] Referring to FIGS. 1 and 2 , an endless belt 10 is shown extending through a serpentine path. Typically, the endless belt 10 is mounted on the front of an engine 11 for driving various accessories or components. Alternatively, the endless belt 10 may also be a chain, particularly timing systems, as is known in the art. The curved serpentine path is defined by six pulleys 12 , 14 , 16 , 18 , 20 , 22 and a tensioner pulley 24 . The pulleys 12 , 14 , 16 , 18 , 20 are shown here by way of example, although not every internal combustion engine includes all of these pulleys. In the present example, the pulleys are as follows: a crank shaft pulley 12 , an alternator pulley 14 , an idler pulley 16 , a power steering pulley 18 , an air conditioning pulley 20 and a water pump pulley 22 . Depending on the location and size of the pulley 12 - 24 various percentages of the periphery of each of the pulleys 12 - 24 are engaged by the belt 10 .
[0029] The belt 10 can transfer in excess of 3000 Newtons of force for driving the various components of the internal combustion engine. Typical forces required to drive an accessory drive or timing drive vary widely with the engine and application. However, in most cases, a typical force range is somewhere in the region of 300 N to 500 N, when measured on the “slack side” of the belt. A typically low applied belt tension would be in the 100 N range. A typically high force range is somewhere in the range of 1000 to 2000 N.
[0030] Referring to FIG. 3 , a graph illustrates the relationship between the torsional vibrations in degrees versus the speed of the engine in RPM on two components of the engine, namely the alternator pulley and the air conditioner compressor pulley for a typical four cylinder engine. As is illustrated, relatively high torsional vibrations are observed at about 500 to 750 RPM and as the engine speed increases, the torsional vibrations diminish.
[0031] Referring now to FIGS. 4 and 5 , a rotor or pulley 12 of the present invention is illustrated. The pulley 12 generally comprises a hub 32 , a rim 34 and a plurality of circumferentially spaced torque transfer sleeves 36 . Inside each sleeve 36 is a drive actuator 38 .
[0032] Hub 32 is configured for mounting on the end of the crankshaft of the engine. Hub 32 is oriented on the crankshaft relative to the top dead center mark. Hub 32 is provided with an axle 33 . A pair of copper sleeves 35 , 37 is mounted for rotation with the axle 33 and hub 32 . An electrical connection 39 is provided from sleeve 35 to each of the actuators 38 , presenting a first voltage rail. An electrical connection 41 is provided from sleeve 37 to each of the actuators 38 , presenting a second voltage rail. A pair of brushes 43 , 45 is mounted to engage the sleeves 35 , 37 , respectively, to provide current to the sleeves 35 , 37 as the hub 32 rotates. Each of the brushes 43 , 45 are connected to a satellite controller 52 .
[0033] Rim 34 is generally ring shaped, having an outer circumferential surface 42 . The outer circumferential surface has poly-V grooves, which are conventional in the art. Rim 34 is relatively stiff but is capable of a degree of flexibility or malleability. Preferably, rim 34 is molded from an organic resin material, such as Nylon. Additional reinforcement materials, such as glass fibres, nano particles, may be added to increase strength. On a conventional sized engine, the rim 34 must be capable of repeatably flexing about 4 mm in diameter along the major diameter.
[0034] Each of sleeves 36 consists of an inner sleeve 44 and an outer sleeve 46 . The inner sleeves 44 are mounted to the hub 32 and the outer sleeves 46 are mounted to the rim 34 . The sleeves 44 , 46 slide relative to each other yet provide a driving connection between the hub 32 and the rim 34 enabling torque to be transferred from the crankshaft 13 to the belt 10 . Sleeves 36 provide a flexible driving connection between the hub 32 and the rim 34 . As is now apparent to those skilled in the art, the particular arrangement of the sleeves could be reversed without departing from the present invention. Additionally, other flexible driving arrangements, such as a rubber ring may also be utilized to provide the flexible driving connection.
[0035] The number of sleeves 36 will depend upon the number of cylinders of the engine. For example, a four cylinder or V-8 engine will preferably have four or multiples of four actuators 36 . An inline six or V-6 engine will preferably have three or multiples of three actuators 36 .
[0036] Inside each sleeve is a drive actuator 38 . In the present embodiment, actuator 38 is a shape memory alloy (SMA) actuator, as is well know in the art. Examples of such actuators are detailed in U.S. Pat. No. 6,390,878, www.steadlands.com and http://www.cim.mcgill.ca/˜grant/sma.html. Other drive actuators such as solenoids may also be substituted.
[0037] Upon application of an electrical current, the actuator 38 will responsively expand or retract depending upon the polarity of the current. The actuators 38 will be electrically connected such that certain ones of the actuator 38 will contract and others will expand upon application of an electric current. As illustrated in FIG. 5 , two diametrically opposed actuators will expand and the other two diametrically opposed actuators will contract, causing the rim 34 to move from a circular configuration to a non-circular profile or configuration, in this example, oval.
[0038] The oval profile of rim 34 has at least one reference radii, in the present example reference radii 50 a and 50 b, which together form the major axis 50 of the oval and a minor axis 51 . Each reference radius 50 a, 50 b passes from the centre of the rotor 12 and through the centre of the respective protruding portion 52 , 53 . The angular position of the non- circular profile is related to a reference direction of the rotor 12 , the reference direction being the direction of a vector or imaginary line 54 that bisects the angle or sector of wrap of the continuous loop belt 10 around the rotor 12 . This vector that bisects the angle of wrap is in the same direction as the hub load force produced by engagement of the belt 10 with the rotor 12 when the belt drive system is static. It should be appreciated, however, that the hub load force direction changes dynamically during operation of the belt drive system. The timing of the non-circular profile is set to be such that, at the time when the torsionals are at a maximum, the peak torsional point, the angular position of the reference radius 50 a is about 90° (four or eight cylinders) to 120° (three or six cylinders) from the reference direction of the angle of wrap bisection 54 ( FIG. 6 ), taken in the direction of rotation of the rotor 12 .
[0039] The magnitude of the eccentricity of the non-circular profile is determined with reference to the amplitude of the peak torsional. In some arrangements the amplitude of the torsional may be substantially constant, and in other arrangements the amplitude of the fluctuating torsional may vary, as illustrated in FIG. 3 . Where the amplitude of the fluctuating torsional is constant, the magnitude of the eccentricity is determined with reference to that substantially constant amplitude of fluctuating torsional. Where the amplitude of the fluctuating torsional varies, the value thereof which is used to determine the magnitude of the eccentricity will be selected according to the operating conditions in which it is desired to eliminate or reduce the unwanted vibrations.
[0040] For each engine, the dynamic peak torsional point can be measured relative to the crankshaft angle. The orientation of the rotor 12 of the present invention relative to the crankshaft can be predetermined. In particular, the minor reference radius 50 is positioned within the first quadrant of the belt wrap a with the peak torsional point.
[0041] Referring to FIG. 6 , a schematic of a typical engine is illustrated. The arrangement is similar to the schematic of FIG. 1 . Both arrangements are provided for illustration purposes only. Tensioner 56 is provided with a position sensor 58 . Position sensor 58 measures the relative position of the tensioner pulley 24 and generates a tensioner position signal. Take-up pulley 60 is also provided with a position sensor 62 . Position sensor 62 measures the relative position of the take-up pulley and generates a take-up pulley signal. The tensioner position signal and the take-up pulley signal are proportional to belt tension on the respective sides of pulley 12 or the present invention. The two signals are fed into a controller 64 . Controller 64 also receives inputs 66 from other vehicle sensors to provide information such as engine speed, and engine load. Controller 64 compares the signals to determine if the engine is experiencing relatively high torsionals. The controller 64 responsively sends a signal to satellite processor 52 to energize the actuators 38 in a first polarity, altering the profile or configuration of the pulley 12 from circular to non-circular. Once the controller 64 determines that the engine is operating in a range outside of the relatively high torsionals, the controller 64 sends a signal to the satellite processor 52 , which responsive energizes the actuators 38 in a second polarity, opposite the first polarity, returning the pulley 12 to a circular profile or configuration.
[0042] Referring to FIGS. 7-10 , a second embodiment of the present invention is illustrated. The pulley 212 is conventional in design in that the pulley 212 has a hub 232 and a rim 234 . Preferably, pulley 212 is made of sheet steel according to U.S. Pat. No. 4,273,547. The outer rim 234 is provided with cut-outs or openings 236 , preferably diametrically opposed. A series of inertia elements 238 are pivotally mounted on the hub 232 at pins 240 . Each inertia element 238 has head portion 244 and a tail portion 246 . The inertia elements 238 are each connected to a spring 242 at the tail end 246 . The head portion has a series of V-grooves, matching the V-grooves of the outer rim 234 . The inertia elements 238 are mounted to pivot between a non-circular profile position ( FIGS. 7 and 10 ) and a circular profile position ( FIGS. 8 and 9 ).
[0043] The spring rate of springs 238 and the mass of the inertia elements 238 , particularly the ratio of the tail portion 246 versus the head portion 244 , is selected such that at low RPM the spring 242 urges the inertia element 238 to pivot about pin 240 to extend the head portion 244 outwardly. In this non-circular profile position, the head portion 244 extends outwardly from the circumferential extent of the outer rim 234 , presenting a series of lobes or bumps. At higher RPM, the inertial forces overcome the spring forces causing the inertia elements 238 to pivot about pin 240 to retract head portion 244 , presenting a generally circular profile on the outer rim 234 .
[0044] Optionally, the springs 238 could be replaced or supplemented with actuators, preferably SMA actuators.
[0045] As with the first embodiment, the number of inertia elements depends on the number of cylinders of the engine. For four and eight cylinder engines, the pulley 212 of the present invention has two or four inertia elements 238 . For six or twelve cylinder engines, the pulley 212 has three or six inertia elements 238 . Positioning of the lobes or bumps relative to TDC is determined in the same fashion as the first embodiment. The present embodiment is passive device, only responsive to RPM of the engine.
[0046] Referring to FIGS. 11 and 12 , a third embodiment of the present invention is illustrated. This embodiment 312 is similar to the first embodiment in that it is a dynamic or active device. In this embodiment, a piezoelectric stack 338 is mounted to the hub 332 . The rim 334 has a series of apertures in the V-grooves. The stack 338 has a head portion 344 that is configured to correspond with the poly-V grooves of rim portion 334 . The pulley 312 is provided with an electrical connection similar to the first embodiment. Upon energizing the stack 338 , the head portion 344 extends outwardly to present a non-circular profile. Upon de- energizing the stack 338 , the head portion 344 retracts inwardly to present a circular profile.
[0047] Referring to FIGS. 13 and 14 , a fourth embodiment of the pulley of the present invention is illustrated. Pulley 412 has a hub 432 connected to a rim 434 . Preferably, hub 434 has a non-circular profile having a major axis 450 of an oval. Preferably, hub. 432 and rim 434 are relative stiff but flexible, molded with an organic resin material. Hub 432 must be capable of stretching along the minor axis about 4 mm. Apertures could be provided in hub 432 to allow for such movement.
[0048] The center of the spreader 452 operatively engages a rod 454 the is connected to an hydraulic plunger 456 of cylinder 457 . Cylinder 457 communicates with the oil lubricating network of the engine via passageway 458 . Return spring 460 provides a return force on the hydraulic plunger 456 .
[0049] A spreader 452 is mounted along the minor axis of the oval. The spreader 452 is generally sigma-shaped in cross section with the upper and lower portions engaging the inner face of rim 434 .
[0050] At low RPM, the engine oil pressure is also low. The hydraulic forces acting on plunger 456 is low allowing the spring 460 to retract rod 454 . In this condition, the outer rim 434 will present a non-circular profile. As the RPM increases, so does the engine oil pressure. The hydraulic cylinder 456 begins to overcome the bias of the spring 460 to extend the rod 454 . As the rod 454 extends, the spreader 452 urges the minor axis of the outer rim 434 to move outwardly to present a generally circular profile.
[0051] Referring to FIG. 15 , a fifth embodiment is illustrated. In this embodiment, the rotor 512 has a non-circular profile having a major axis 550 defined by reference radii 550 a and 550 b and a minor axis 551 . The rotor 512 has a hub 532 and an outer rim 534 . The rotor 512 is provided with an orientation indicia or other marking to enable the rotor 512 to be installed on an end of crankshaft in a predetermined orientation. Hub 532 has a reference mark 552 , which is located at a predetermined angle θ relative to one of the major reference radii 550 a or 550 b. Alternatively, the hub 532 can be provided with a key way 554 enabling the pulley 512 to be mounted on the crankshaft in only one predetermined orientation. Other known methods of mounting devices in a predetermined orientation may be apparent to those skilled in the art and are incorporated herein.
[0052] Many modifications and variations of the invention are possible in light of the above teachings. Therefore, within the scope of the appended clairns, the invention may be practiced other than as specifically described. | A pulley has a hub and a rim. The hub is configured to be mountable on a driving shaft. A driving connection between the hub and rim is provided. In a first embodiment, a drive mechanism is operable to configure the rim between a circular profile and a non-circular profile. The non-circular profile produces a counteracting torque to offset load torques produced by the engine. The drive mechanism can be electrical, inertial, hydraulic or any combination thereof. In a second embodiment, the rim is fixed with a non-circular profile. | 5 |
FIELD OF INVENTION
[0001] The present invention relates to an improved process for the preparation of Clopidogrel bisulfate crystalline form-1 of formula I from (S)-methyl-2-(2-thiophen-2-yl) ethylamino)-2-(2-chlorophenyl) acetate hydrochloride of formula II. The present invention also provides a highly pure crystalline form of Clopidogrel bisulfate from (S)-methyl-2-(2-thiophen-2-yl) ethylamino)-2-(2-chlorophenyl) acetate hydrochloride of formula II without any degradation of Clopidogrel base.
[0000]
BACKGROUND OF INVENTION
[0002] (S)-(+)-(2-chlorophenyl)-2-(6,7-dihydro4H-thieno[3,2c]pyridine-5-yl-acetate hydrogen sulfate, known for platelet aggregation inhibitor, drug having International Nonproprietary Name [INN] Clopidogrel hydrogensulfate.
[0003] Clopidogrel is administrated as it bisulfate salt and currently being marketed under the brand name PLAVIX™.
[0004] Clopidogrel hydrogen sulfate was first revealed in U.S. Pat. No. 4,847,265 assigned to Sanofi SA and was claimed as dextrorotatory isomer of methyl α-5(4,5,6,7-tetrahydro (3,2-c) thieno pyridyl) (2-chlorophenyl)-acetate and its salts. The separation of enantiomers [dextrorotatory enantiomers and leavo rotatory enantiomers] from the racemic mixture of methyl α-5(4,5,6,7-tetrahydro(3,2-c)thieno pyridyl) (2-chlorophenyl)-acetate in the specification as illustrated in Scheme-1 of U.S. Pat. No. 4,847,265 (as given below)
[0000]
[0005] The product is characterized by its melting point and optical rotation, which are 182° C. and [α] D 20 =+51.61 [c=2.044 g/100 ml, methanol] respectively. The specification does not deal with the crystalline form of Clopidogrel hydrogen sulphate prepared in this way.
[0006] EP99802 provides a new process for the preparation of Clopidogrel bisulfate. JP4230387 also discloses the process for the preparation of (+)-Clopidogrel bisulfate in detail with a few modifications.
[0007] The polymorphic forms 1 and 2 for Clopidogrel bisulfate were first revealed in U.S. Pat. No. 6,504,030 assigned to Sanofi. It reveals that Polymorphic form-1 was prepared according to the method described in U.S. Pat. No. 4,847,265. Polymorphic form-1 is specified as monocline crystal form, characterized by X-ray Diffraction pattern and Infrared spectrum.
[0008] Melting point and Optical rotation of polymorph form are 184° C. and [α] D 20 =+55.10 [c=1.891/100 ml, methanol], respectively. Its melting point of 176° C. characterizes the orthorhombic polymorph form 2.
[0009] The study of polymorphic forms 1, 2, 3, 4, 5 and its preparations are extensively revealed in U.S. Pat. No. 7,074,928 assigned to Teva Pharmaceutical Industries Ltd.
[0010] U.S. Pat. No. 6,429,210 discloses that Form 2 exhibits a lower solubility than Form 1 as a result of its greater thermodynamic stability
[0011] U.S. Pat. No. 7,291,735 discloses a process for the preparation of blood-platelet aggregation inhibiting agent, in particular Methyl-(+)-(S)-.alpha.-(2-chlorophenyl)-6,7-dihydrothieno [3,2-c]pyridine-S-(4H)acetate bisulfate Form-1. It also reveals the preparation of 99.96% pure (+)(S)-Clopidogrel from the racemic mixture of Clopidogrel base. The obtained (+)(S)-Clopidogrel is dissolved in ethyl acetate and treated with Concentrated sulphuric acid followed by the seeding with Clopidogrel bisulfate form-1 to prepare (+) (S)-Clopidogrel bisulfate crystals.
[0012] US Patent Application 2006047121 reveals a process for the preparation of Clopidogrel bisulfate form-1 from form-2. It reveals that form-1 was prepared by dissolving form-2 in C 1-4 carboxylic acid followed by the addition of antisolvent i.e. dimethyl ether; diethyl ether; and diisopropyl ether.
[0013] European patent 1554284 reveals the process for the preparation of hydrogen sulfate (α-S) of α-(2-chlorophenyl)-6,7-dihydro-thieno[3,2c]pyridine-5(4H)-acetic acid methyl ester in crystalline form 1, which comprise the separating out of a solution of Clopidogrel in form of a free base or salt in a solvent selected form primary, secondary or tertiary C 1-5 alcohols or their ester with C 1-4 carboxylic acids or optionally their mixture.
[0014] PCT Application 2008118030 reveals a process for the preparation of substantially pure Clopidogrel Bisulfate form-1. It reveals the preparation of form-1 by treating sulfuric acid with optically active Clopidogrel base in the presence of mixture of at least two solvents. The first one chosen from group I, comprising aliphatic ethers, and the second one from group II, comprising ketones, esters of C 1-5 carboxylic acids and C 1-4 aliphatic alcohols, primary, secondary and tertiary aliphatic C 1-4 alcohols.
[0015] US Patent Application 2009247569 reveals a process for the preparation of Clopidogrel Bisulphate form-1 comprising, dissolving Clopidogrel base in an organic solvent like C 6 ketone, C 6-12 aromatic hydrocarbon to obtain the solution; and addition the sulfuric acid to the solution. It also reveals a novel process for the preparation of. Form-1, comprises dissolving Clopidogrel base in MTBE (methyl-t-butyl-ether), cooling, adding formic acid or acetic acid to obtain a cooled solution; and adding the cooled solution to a mixture of sulfuric acid and MTBE (methyl-t-butyl-ether) at a temperature less than about 40° C.
[0016] The above-mentioned prior-art methods are inconsistent in the presence Form2, which is one of the major impurity. So, there exists a need for still further improvement of the economical process for the production of Clopidogrel Bisulfate, with high purity and without detectable minimized polymorphic impurities specifically Form-2.
[0017] The present invention provides a novel and industrially feasible process for the preparation of form-1 crystalline form of Clopidogrel hydrogen sulfate minimized polymorphic impurities and the crystalline form-2.
SUMMARY OF THE INVENTION
[0018] The present invention reveals the novel process for the preparation of Clopidogrel bisulfate in crystalline form-1 from (S)-methyl-2-(2-thiophen-2-yl) ethylamino)-2-(2-chlorophenyl) acetate hydrochloride without any degradation of Clopidogrel base.
[0019] Clopidogrel bisulfate crystalline form-1 obtained in the current process is of highly pure.
[0020] In one embodiment of the present invention Clopidogrel base is not isolated and is directly obtained as form-1.
[0021] In yet another embodiment, present invention is useful to control the OVI [Organic Volatile Impurities] impurities as per the guidelines of ICH [International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use].
DETAILED DESCRIPTION OF THE INVENTION
[0022] The present invention relates to an improved process for the preparation of Clopidogrel Bisulfate crystalline Form-1 of formula from (S)-methyl-2-(2-thieno-2-yl)ethylamino)-2-(2-chlorophenyl) acetate hydrochloride of formula II. The present invention also provides a highly pure crystalline form of Clopidogrel bisulfate from (S)-methyl-2-(2-thieno-2-yl)ethylamino)-2-(2-chlorophenyl) acetate hydrochloride of formula II without any degradation of Clopidogrel base.
[0023] The improved process for the preparation of Clopidogrel bisulfate form-1 of formula (I) comprises steps of:
[0000]
i. (S)-methyl-2-(2-thiophen-2-yl)ethylamino)-2-(2-chlorophenyl) acetate hydrochloride of general formula II is treated with 37-41% WN formaldehyde solution at a temperature of 25-30° C. and then to a temperature raised to 50-55° C.
[0000]
ii. The reaction is then cooled to a temperature of 25-30° C. and is continued until (S)-methyl-2-(2-thiophen-2-yl)ethylamino)-2-(2-chlorophenyl) acetate hydrochloride content reaches to <0.5%. The reaction is then cooled to a temperature range of 5-10° C.
iii. C 1-4 alcohol, C 1-5 carboxylic acid ester are added to the reaction and then pH is adjusted to a range of 7-8 by employing a base. The reaction is heated to a temperature of 25-30° C.
iv. Aqueous layer and organic layers are separated and aqueous layer is further extracted with C 1-5 carboxylic acid ester.
v. Combined C 1-5 carboxylic acid ester layer is washed with 1-20% sulphuric acid solution to remove the impurities.
vi. Then C 1-5 carboxylic acid ester layer is washed with inorganic base solution followed by water.
vii. The organic layer obtained is treated with activated charcoal at a temperature of 25-30° C. for about 20-30 minutes. The reaction mass is then filtered. viii. Sulfuric acid dissolved in C 1-5 carboxylic acid ester is added to the filtered reaction mass at a temperature of −10-0° C. for about 90-120 minutes.
ix. C 1-5 carboxylic acid is added slowly to the reaction mass for 30-45 mins at the same temperature. The reaction mass is heated to a temperature of 25-30° C. and is maintained for 20-24 hrs.
The precipitated solid is filtered, washed with C 1-5 carboxylic acid ester; the suck dried cake is washed with Acetone.
x. The crystalline material obtained is dried at 40-45° C. under vacuum until LOD and OVI reaches as per limit.
Schematically the present process can be represented as:
[0000]
[0034] (S)-methyl-2-(2-thiophen-2-yl)ethylamino)-2-(2-chlorophenyl) acetate hydrochloride (obtained from known methods of prior art), formaldehyde employed in step (i) are 1 w/w and 8 V/W respectively. C 14 alcohol employed in step (iii) is selected from the group of simple acyclic alcohol, preferably methanol. C 1-5 carboxylic acid ester is ethyl acetate, n-butyl acetate etc., preferably n-butyl acetate.
[0035] Inorganic base employed in step (vi) is alkali metal carbonates or bicarbonates, preferably sodium bicarbonate, more preferably 5% sodium bicarbonate and C 1-5 carboxylic acid employed in step (ix) is acetic acid
[0036] Sulfuric acids, C1-5 carboxylic acid employed in step (viii), step (ix) are 1 mole equivalent of the reaction mass.
[0037] pH of the solution in step (vi) i.e. after using inorganic base is in the range from 7 to 8.
[0038] Employing C1-5 carboxylic acid esters in step (iii) will provide the improved quality of the final product.
[0039] Employing C 1-4 alcohol in step (iii) is providing the improved quality, particularly control of the other surplus isomer along with three mysterious impurities.
[0040] Washing of C 1-5 carboxylic acid ester layer with 1% sulphuric acid solution to remove the major tricky mysterious impurities excluding the methanol controlled.
[0041] After the acidic wash pH of the reaction mass is adjusted to a range of 7-8 by employing inorganic base wash followed by water wash. If the above operation is not conducted during the formation of Form-1, infrequently no solid separation and even the separated content will also be gummy in nature.
[0042] Subsequently, water is removed from the organic layer by applying high vacuum 1-2 mbar at a temperature range of 30-40° C. This will provide the best results for water removal and the usage of drying agents can also be avoided.
[0043] The above step is very crucial, without the water removal operation further proceeding into the reaction leads to Form-2.
[0044] A high volume of C 1-5 carboxylic acid ester is preferable to avoid the formation of form-2. And employing C 1-5 carboxylic acid also avoids the formation of form-2.
[0045] Cyclohexane washing in the final stage while preparing form-1 of Clopidogrel bisulfate is useful for controlling the OVI impurities as per the guidelines of ICH.
EXAMPLES
Example—1
Clopidogrel Bisulfate Form-1
[0046] (I) (S)-methyl-2-(2-thiophen-2-yl)ethylamino)-2-(2-chlorophenyl) acetate hydrochloride is treated with 37-41% W/V formaldehyde solution at a temperature of 25-30° C. and then slowly heated to a temperature of 50-55° C. and continued until (S)-methyl-2-(2-thiophen-2-yl) ethylamino)-2-(2-chlorophenyl)acetate hydrochloride content reaches to <0.5%. The reaction is then cooled to a temperature range of 5-10° C. Methanol, n-butyl acetate are added to the reaction and then pH is adjusted to a range of 7-8 by employing a base. The reaction is heated to a temperature of 25-30° C. Aqueous layer of reaction mass is further extracted with n-butyl acetate and then the layers are combined. n-Butyl acetate layer is washed with 1% sulphuric acid solution to remove the impurities. Now, the n-butyl acetate layer is washed with 5% sodium bicarbonate solution followed by water. Distilled off about 10% of the n-butyl acetate under vacuum till the moisture content is below 0.5%. The pre-dried Activated Charcoal is added to the organic layer at a temperature of 25-30° C. for 20-30 minutes. The reaction mass is then filtered for making particle free.
[0047] (II) Sulfuric acid dissolved in n-butyl acetate is added to the filtered reaction mass at a temperature of −10-0° C. for 90-120 minutes. Acetic acid is added slowly to the reaction mass for 30-45 minutes at the same temperature. The reaction mass is heated to a temperature of 25-30° C. and is maintained for 20-24 hours. The gummy free material is filtered, washed with n-butyl acetate, kept under suck dry for 30-60 minutes. Now, the cake is washed with acetone and kept under suck dry for 30-60 minutes. The obtained crystalline material is dried at 40-45° C. under vacuum until LOD and OVI reaches as per limit. | An improved process for preparing crystalline form-1 of (S)-methyl 2-(2-chlorophenyl)-2-{6,7-dihydrothieno[3,2-c]pyridine-5(4H)-yl}acetate bisulfate (clopidogrel bisulfate) of formula I is provided The preparation comprises the straight conversion of an uncyclized material of (S)-methyl 2-[2-(thiophen-2-yl)ethylamino]-2-(2-chlorophenyl) acetate hydrochloride into clopidogrel bisulfate crystalline form-1 without any degradation of clopidogrel base | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention.
[0002] This invention relates to hoists used in building concrete walls and in particular to a wall climbing form hoist for handling form units in the construction of concrete wall structures for multi-story buildings.
[0003] 2. Background of the Prior Art.
[0004] In the construction of a multi-story building, such as an office building, apartment building and the like, these buildings may have thirty or more floors. Where concrete is used in the construction of the outside or inside walls, it is necessary to provide cranes in the setting up and then stripping of the forms from a set wall panel for reuse in continuing the completion of the wall. Unless a crane is available as required in the setting up and stripping of the forms the wall not only becomes costly, but additional cost increases are incurred by lost time on other operations, that must be performed on a meshing or synchronized time schedule with the wall forming operation. It is apparent also that appreciable down time of the crane may take place, when it could be more efficiently utilized on other jobs at the building site. Where open crane time for timely handling of the form units is not available, construction usually proceeds behind schedule with resultant monetary losses. In some instances, the size of the building being constructed relative to the building site may preclude the use of a crane.
[0005] A system for constructing concrete walls about two stories high is shown in U.S. Pat. No. 2,516,318; and for multi-story buildings, in U.S. Pat. Nos. 4,043,087; and 2,118,374. Self-lifting form systems now in use are generally cumbersome and, although inconvenient to manipulate during both a wall climbing operation and a form handling operation, have been found to be generally satisfactory. U.S. Pat. No. 3,628,223 discloses a climbing form hoist that includes a telescopic mast comprised of a pair of vertical lower mast sections for telescopically receiving associated upper mast sections which are extended and retracted by a common reversible electric motor. The upper mast sections carry an outer form unit. With the mast retracted and attached at its lower end to a completed lower wall section, the inner and outer form units are braced or tied together in any well-known manner after which a new lift or wall section is poured. When the new pour has set, the outer form unit, after being stripped from the wall structure, is elevated by the extension of the upper mast sections to a new pour position wherein its lower end is attachable to the previously poured wall section. The lower mast sections are then released from the wall, the upper mast section is retracted and the lower mast section again connected to the wall. The inner form unit is then repositioned for another lift to be poured.
[0006] U.S. Pat. No. 4,290,576 discloses a climbing scaffolding which utilizes a guiding rail only as a vertical guide, but not to support the load resulting from the weight of the scaffolding in the vertical direction. The '576 patent requires its operators to manually fix the scaffolding in its lifted position by inserting pins into cutouts or by placing wedges underneath to support the load. U.S. Pat. No. 5,000,287 discloses a displaceable platform which is movable sectionwise on a wall, comprising support shoes, carrying rails, and a bracketing arrangement to support the platform. The thrust of the '287 patent is the correction of non-uniform upward travel of its displacement elements through very small advancements on a toothed displacement rack and a common drive and controller apparatus that prohibits further upward displacement until all linear drives have completed the preceding working step or one of the proceeding working steps. While the ratcheting mechanism of the '287 patent's tooth displacement rack may provide for fewer incidents of jamming, therefore minimizing related down time due to mechanical failures, the construct of the present invention is designed such that the platform will move in a substantially level manner without the need to correct the movement along one rail while fixing the position of the platform along another rail.
[0007] U.S. Pat. No. 5,630,482 discloses a self-climbing device which utilizes two types of scaffolding shoes: one for guiding and one for guiding and exhibiting attachment devices; two types climbing heads: a lower head with a pivotable member supported by a sidewall enclosure, and an upper head with a pivotable member supported by two additional housing walls provided between the outer housing walls of the sidewall enclosure; and two types of protuberances extending from a guide rail which provide, in a plurality of steps, a locking and loosening means by which a platform may be lifted or lowered along the length of a mounting rail. The present invention alleviates much of the complexity of the '482 patent by providing a simplified means for alternately supporting the wall climbing form hoist and moving the mounting rail or mast by utilizing one type of mounting support and a simplified mounting rail or mast.
SUMMARY OF THE INVENTION
[0008] the wall climbing form hoist of the present invention provides for an appreciable reduction both in the amount of labor and crane time required in the construction of multistory outside or inside concrete walls (for example interior core shafts like stairwells and elevator shafts). The hoist is efficient in operation to handle both the inside and the outside form units for the pouring and setting of successive lifts or horizontal wall sections and is readily adapted for handling form gangs. The hoist is hydraulically operated and remotely controlled and includes a platform or scaffold upon which workmen can be safely carried. A base or supporting frame carries the platform and the outer form unit. A pair of masts are releasably secured to a lower section of the poured concrete wall and movably carried on the base frame for relative up and down movement by a hydraulic cylinder and a pair of ratcheting dog latch assemblies, a movement much like that undertaken in the operation of a common car jack, where a human arm provides a force like that of a hydraulic cylinder on a ratcheting means which displaces a vehicle while preventing the reversal of such a displacement
[0009] With the first two stories of the concrete wall structure previously constructed in any suitable manner, two pair of mounting supports are secured to the poured wall sections and the hoist is lifted in position by a crane or suitable alternative means to provide for the securement of the masts to the wall and the setting of the outer form unit and an inner form unit for a new pour. When the new pour has set, the support frame is supported on the upper mounting supports and the hydraulic cylinder and latch dog assemblies are used to move the masts upwardly a story height. The support frame is moved upwardly relative to the masts to locate the form unit in a next pour position wherein the lower end thereof is attached to a base sill secured to the set pour. A new pour is then made and the cycle of operations repeated until a desired height of the wall structure is attained. A further advantage of the invention is its ability to overcome uneven sections of poured wall through the utilization of shims mountable when necessary between the wall and the wall mounting assemblies. In an embodiment of the invention, linear activators are positioned such that the base frame and masts are manipulated to lower the climbing form hoist a distance equal to the length of its ascent path, or a portion thereof. In another embodiment of the invention a crane is utilized to lower the climbing form hoist to the ground.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is a side elevational view of the wall climbing form hoist of the present invention shown attached to a concrete wall that is being formed by the wall climbing form hoist.
[0011] [0011]FIG. 2 is a front view of the wall climbing form hoist with parts of the associated scaffolding removed for clarity.
[0012] [0012]FIGS. 3 a - 3 d are side elevational views showing the climbing action of the wall climbing form hoist of FIG. 1.
[0013] [0013]FIGS. 4 a - 4 b are enlarged detail views of a mount base assembly that is used for supporting portions of the wall climbing form hoist on a moveable mast.
[0014] [0014]FIGS. 5 a - 5 c are a front view, top view, and side view, respectively, of dog latch assembly.
[0015] [0015]FIGS. 6 a and 6 b are front and side views, respectively, of a mast assembly of the present invention.
[0016] [0016]FIG. 7 is an enlarged detail view of the upper end of the mast assembly of FIG. 6 b.
[0017] [0017]FIG. 8 is an enlarged detail view of a hydraulic cylinder extending between upper and lower dog latch assembliew of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Referring to FIG. 1 of the drawings, the wall climbing form hoist of this invention, indicated generally at 20 , is illustrated as including a platform or support frame 22 which is supported for vertical movement on a pair of masts 24 and 26 which are of an I-shape in transverse cross section. The support frame 22 adjustably carries a vertical form panel 28 for sliding movement toward and away from an outer surface of a concrete wall 30 being constructed.
[0019] As best illustrated in FIG. 2, a rear flange of each of the masts 24 and 26 are guideably received inside a pair of wall mounting bases, upper wall mounting base 32 and lower wall mounting base 34 . The wall mounting bases 32 and 34 are releasably secured to the concrete wall 30 , typically by bolts (not shown) which are received in throughbores formed in the wall 30 .
[0020] The support frame 22 includes an upper deck assembly 36 and a lower frame assembly 38 which depends therefrom. The lower form assembly 38 consists of sufficient horizontal, vertical, and diagonal frame members to complete a generally box shaped lower frame assembly 38 . A pair of upper dog latch assemblies 40 and 42 are received in a pair of platform mounting assemblies 44 and 46 which in turn are secured to the upper deck assembly 36 on the right and left sides thereof, respectively. As will be described in more detail below, the dog latch assemblies are operated to alternatively engage in release from the mast to assist in the self-climbing action of the wall form hoist 20 .
[0021] The platform mounting assemblies 44 and 46 are slideably received about the forward flange of the corresponding one of the masts 24 and 26 , in the same manner as the wall mounting bases 32 and 34 slideably receive the rear flange of the masts 24 , 26 . The platform mounting assemblies 44 and 46 (FIG. 4) assist in maintaining the relative alignment of the wall climbing form hoist 20 as it climbs the concrete wall 30 and also, as will be described in more detail below, support the weight of the wall form hoist 20 while the masts are being moved.
[0022] As recited above, the masts 24 and 26 are slideably received inside the wall supports 32 and 34 . Because the masts 24 and 26 freely slide within the channels of the wall supports 32 and 34 , they must be supported to maintain their adjusted positions. One means of support is a pivotable finger 50 (see FIGS. 6 and 7) mounted at the top of the masts 24 and 26 . As the masts 24 and 26 are moved upwardly, the finger 50 will come into contact with the wall supports 32 and 34 . The shape of the fingers 50 will cause it to pivot out of the way to allow the upper end portion of the masts 24 , 26 to pass above the wall support 32 , 34 . Thereafter, if the masts 24 , 26 are released, the finger 50 will engage the upper edge of the wall support 32 , 34 and prevent the mast from dropping further.
[0023] The dog latch assemblies 40 and 42 are illustrated in detail in FIGS. 5 a - 5 c. Each dog latch assembly 40 , 42 includes a mounting collar 52 that includes a channel 54 which accommodates the foward flange of the masts 24 , 26 . A dog 56 is mounted for pivotable movement about a horizontal axis located centrally of the dog 56 and defined by a horizontal mounting pin 58 . The dog is pivotable between a first position in which a lower end portion of the dog 56 is extended by spring 57 into the area between the channels 54 and a second position which an upper end portion of the dog 56 is extended by spring 57 between the channels 54 . The first position is illustrated in FIG. 5 c. The pivot of the dog 56 between the first and second positions can be accomplished manually by repositioning handle 61 (FIG. 8), or through the action of a hydraulic cylinder (as shown in FIGS. 1 and 3). Elongated hole 63 allows sufficient mobility during dog pivoting operations between the first and second positions.
[0024] As illustrated in FIG. 6, the outwardly facing face of forward flange of the masts 24 , 26 , include a plurality of regularly spaced cleats 60 . The upper and lower end portions of the dog 56 are shaped with a notch 62 which are adapted to engage the cleats 60 as will be described in more detail.
[0025] Below each of the upper dog latch assemblies 42 on either side of the form hoist 20 is located a lower dog latch assembly 66 . Similar to the upper dog latch assemblies 42 , the lower dog latch assemblies 66 are received about a corresponding one of the masts 24 , 26 for sliding movement vertically relatively thereto. In contrast, however, to the upper dog latch assemblies 42 , the lower dog latch assemblies 66 are only connected to the support frame 22 by a corresponding one of a pair of hydraulic cylinders 64 (see FIGS. 1 and 5). The lower dog latch assemblies 66 are constructed nearly identically to the upper dog latch assemblies 42 in that they also include a pivotable dog that can move into and out of supporting contact engagement with the cleats 60 of either of the masts 24 , 26 .
[0026] The construction of the dog latch assemblies 42 and 66 act to support the weight of the wall climbing form hoist 20 by contact engagement of the notches 62 with the upper portion of a corresponding one of the cleats 60 so that once the dog latch assembly 42 , 66 is raised to a position such that the lower proximate end portion of the dog 56 just clears the upper surface of a corresponding one of the cleats 60 , the dog latch assembly 42 , 66 can be loaded and it will latch into place supporting the full weight of the wall climbing form hoist 20 on the masts 24 and 26 . Accordingly, by alternately supporting the wall climbing form hoist 20 on the upper dog latch assembly 42 and then the lower dog latch assembly 66 , the hydraulic cylinder 64 can be used to raise the wall climbing form hoist in a ratchet fashion.
[0027] The action of the wall climbing form hoist 20 will be more fully understood by reference to a description of a cycle of the wall climbing form hoist 20 in pouring a story of a concrete wall for a structure. Initially, two stories of a concrete wall 30 are poured in a conventional fashion. Once the concrete has set, a crane or other independent hoist means is used to lift the wall climbing form hoist 20 into position adjacent the concrete wall 30 . The two pairs of upper mounting supports 32 and 34 are releasably secured to the concrete wall 30 by any suitable means. In this position, as illustrated in FIG. 3 a, the wall climbing form hoist 20 is supported on the upper pair of mounting supports 32 by a pair of mount base assemblies 44 , 46 (FIG. 4). The mount base assemblies 44 , 46 are secured to the upper deck assembly 36 and extend toward the concrete wall 30 . The mount base assemblies 44 , 46 include a channel 70 that is of a size and shape to be received about a corresponding one of the masts 24 , 26 . On either side of channel 70 is located a pivotable finger 74 that is pivotable between a engaging position wherein the projecting portion 72 of the finger 74 extends into the channel 70 . The fingers 72 are positioned so that the projecting portion 74 will engage the top of the upper mounting supports 32 when in the appropriate position and, accordingly, will act to support the wall climbing form hoist 20 . The vertical form panel 28 is advanced towards the wall 30 until it is in position to form the adjacent surface of the next story. A corresponding form panel is positioned on the opposite side of the concrete wall 30 by conventional forming methods or, alternatively, by another wall climbing form hoist. Concrete can then be poured between the opposing forms which are left in place until the concrete cures.
[0028] Once the concrete cures, the vertical form panel 28 is retracted away from the newly formed face of the concrete wall 30 . Another pair of upper mounting supports 34 ′ are releasably attached in the new concrete wall section positioned vertically above the other mounting supports on the lower sections.
[0029] At this time, the hydraulic cylinders 64 are extended, resulting in movement of the lower dog latch assembly 66 downwardly. Once the upper end portion of the dogs 56 clears the lower end portion of a corresponding one of the cleats 60 of the masts 24 , 26 , the hydraulic cylinder 64 is stopped and reversed. Upon reversal, the notch 62 in the upper end portion of the dogs 56 will engage the lower end portion of the corresponding cleat 60 . Further retraction of the hydraulic cylinder 64 will raise the masts 24 , 26 . As the masts 60 move past the dog 56 in the upper latch assembly 42 , the dog 56 will allow the cleats 60 and the masts 24 , 26 to pass. After the hydraulic cylinder 64 has been fully retracted, it is again extended. As it begins its extension, the cleat 60 next above the dog 56 of the upper latch assembly 42 will engage with the upper end portion of the notch 62 in the dog 56 , thus preventing the masts 24 , 26 from falling. This cycle is repeated until the masts 24 , 26 have been raised a full story wherein the upper end portion of the masts 24 , 26 has passed through the newly mounted upper mounting supports. The hydraulic cylinders 64 are then extended until the fingers 50 on the upper end portion of the masts 24 , 26 engage the newly mounted upper mounting supports and thereby support the masts 24 , 26 .
[0030] The hydraulic cylinders 64 are again extended and retracted. This time, however, since the masts 24 , 26 are supported on the upper mounting supports, the lower end portions of the dogs will alternatively engage successive cleats on the masts. Accordingly, the upper dog latch assemblies 42 and the lower dog latch assemblies 66 will alternatively be engaged and supported on the masts 24 , 26 . In this way, the wall climbing form hoist 20 is ratcheted upwardly relative to the masts 24 , 26 (FIG. 3 c ). The entire cycle can then be repeated until the full height of the concrete wall 30 has been poured.
[0031] Once the full height of the wall is poured, the wall climbing form hoist 20 is normally picked off of the building by a crane. Alternatively, The form hoist 20 can be adapted for lowering itself down the formed wall. In this procedure, the masts 24 , 26 and support frame 22 are alternatively and sequentially lowered using the hydraulic cylinders 64 as above, except that the dog latches are manually operated, such as by handle 61 , or a hydraulic cylinder 76 , to allow the latches to clear the adjacent cleat and permit lowering of the platform 22 and masts 24 , 26 , similar in the way in which an automobile jack is operated to lower the automobile. Additionally, a plurality of hydraulic cylinders 78 (FIGS. 4 and 7) are shown for moving of the fingers 50 and 72 to allow the masts 24 , 26 and platform 22 , respectively, to move past the mounting assemblies or bases 32 and 34 . Accordingly, in an embodiment of the climbing form hoist, the movement of the form hoist to a downward position may be effectuated under its own power rather than being picked off by a crane.
[0032] The foregoing description and drawings comprise illustrative embodiments of the present inventions. The foregoing embodiments described herein may vary based on the ability, experience, and preference of those skilled in the art. The foregoing description and drawings merely explain and illustrate the invention, and the invention is not limited thereto, except insofar as the claims are so limited. Those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention. | A self-climbing concrete wall form hoist for forming a concrete wall section atop a previously formed wall section has a wall mounting releasably secured to the previously formed wall section, a moveable vertical mast, a channel in the wall mounting which guideably receives the moveable mast, a platform alternatively supported on the mast and on the wall mounting, upper and lower dog latch assemblies mounted on the platform and pivotable between a platform raising position when the mast is supported on the wall mounting and a mast raising position when the platform is supported on the wall mounting, and an extensible and retractable linear actuator interconnecting the upper and lower dog latch assemblies for raising the platform relative to the mast when the dog latch assemblies are in the platform raising position and for raising the mast relative to the platform when the dog latch assemblies are in the mast raising position. The self-climbing concrete wall form hoist can descend a wall by effectively reversing the steps required to complete wall climbing. | 4 |
PRIORITY CLAIM
This application claims priority of U.S. Provisional Application Ser. No. 60/496,175, filed on 08/19/2003.
TECHNICAL FIELD OF THE INVENTION
The present invention relates to the field of RF antennas and, in particular, dual ridge horn antennas.
BACKGROUND OF THE INVENTION
Among the simplest and probably most widely used antennas is the horn, with applications including use as a feed element for dish antennas, reflectors and lenses, as elements of phased array antennas, for calibration and gain measurements of other antennas and devices, and for electromagnetic compatibility (EMC) testing. The widespread applicability of horns arises from its relative simplicity, ease of construction, ease of excitation, versatility, large gain and performance.
Horn antennas are essentially flared waveguides that produce a uniform phase front larger than the waveguide itself. A commercially available horn antenna is the Model 3115, manufactured by ETS Lindgren. See http://www.ets-lindgren.com/. A three dimensional view of this antenna is shown in FIG. 1 . FIG. 2 shows a bottom view, side view and rear view of the Model 3115. This antenna comprises a connection assembly 1000 , an upper plate 1100 , a lower plate 1200 , and side plates 1001 and 1002 . The dimensions shown are nominal dimensions for the ridged horn antenna designed for operation in the 1 to 18 giga-Hertz (gHz) frequency band. Thus, upper and lower plates 1100 , 1200 are nominally 9.63 inches wide at the wide end 1210 of the flare and 3.63 inches at the narrow end 1220 (bottom view). Upper plate 1100 and lower plate 1200 are each at an angle of +/−13 degrees, 14 minutes from the horizontal, extending 6 inches from connection assembly 1000 . This is referred to herein as a pyramidal horn since the horn formed by the plates is flared in both the E-plane and the H-plane. Connection assembly 1000 provides a connection 1050 to couple power to the antenna from a coaxial cable (not shown). A threaded stud 1003 is provided for mounting the antenna.
FIG. 1 also shows a ridge 1250 attached to lower plate 1200 . A second ridge 1150 of identical contour is attached to upper plate 1100 . A side view and an edge view of a ridge 1150 or 1250 are shown in FIG. 3 . The ridge exhibits a nominal edge thickness of 0.3550 inches and a nominal length of 7.5 inches. The ridge also exhibits a curvature or flare with nominal coordinates in inches as follows:
X 0.000 0.5000 1.000 1.500 2.000 2.500 3.000 3.500 Y 0.000 0.000 0.016 0.032 0.049 0.085 0.133 0.200 X 4.000 4.500 5.000 5.500 6.000 6.500 7.000 Y 0.290 0.422 0.605 0.875 1.265 1.855 2.695
At its widest point, the ridge is 1.66 inches wide. Further, the ridge termination 1151 coincides with the end 1210 of a plate 5100 , 5200 .
The implementation of ridges 1150 and 1250 vastly extends the usable bandwidth of the basic horn antenna. Adding ridges to the horn antenna increases its bandwidth by lowering the cut off frequency of the dominant mode, while raising the cut off frequency of the next higher order mode. A gain pattern for the Model 3115 antenna is shown in FIG. 4 , which shows a substantial gain over the frequency range between one and eighteen gHz. The Voltage Standing Wave Ratio (VSWR) for this frequency range is shown in FIG. 5 , and the half power beam width is shown in FIG. 6 .
A typical normalized radiation pattern of the ridge horn antenna is shown in FIGS. 7 , 8 and 9 , corresponding to 3, 12, and 17 gHz respectively. The preferred pattern is one in which the maximum power is delivered on the main axis (zero degrees), with monotonically decreasing power over a wide angular sector off the main axis. As shown in FIGS. 7 , 8 , and 9 , as frequency increases, the main lobe of the antenna pattern becomes narrower and side lobes increase in power. Moreover, as reported in a recent technical journal, when the frequency of operation increases, the amplitude of off-axis side lobes increases and eventually surpasses the on-axis power. See IEEE Transactions on Electromagnetic Compatibility, Vol. 45, No. 1, February 2003, pages 55–60, Bruns, et.al.
Thus, although the standard ridged horn antenna provides usably high gain over a very broad frequency range, its directivity deteriorates at the high frequency end of that range. This is undesirable in most applications especially when the ridged horn antenna is used for calibration, gain measurements, or EMC testing. For EMC Immunity or susceptibility measurements it is also desirable to have the main lobe of the pattern wide enough to illuminate the equipment being tested, the narrow beam of the 3115 antenna is not well suited for this purpose. Improvement of an antenna's directivity without an increase in the VSWR within the frequency range of operation is difficult. Thus, what is needed is a ridged horn antenna that exhibits improved directivity at the high end of the frequency range for which its gain remains usably high, while providing a relatively low VSWR across the frequency range of operation.
SUMMARY OF THE INVENTION
Accordingly, the present invention presents methods and apparatus for directivity enhancement of a ridged horn antenna that overcome limitations of the prior art. More particularly, a ridged horn antenna, and method of design there for, is presented that exhibits superior directivity at the high end of the frequency range for which its gain remains usably high, while providing a relatively low VSWR across the frequency range of operation.
According to an aspect of the invention, ridges of a ridged horn antenna are provided that exhibit a pronounced curvature extending beyond the end of the plates that form the flared horn.
According to another aspect of the invention, the curvature of a ridge exhibits an arc that is tangent to a line perpendicular to a surface of the plate to which the ridge is affixed.
According to another aspect of the invention, the curvature of a ridge exhibits an acute arc that terminates on a surface of the plate to which it is affixed, the arc being tangent to a line perpendicular to a surface of the plate.
According to another aspect of the invention, an aperture of smaller dimension and a smaller antenna length are achieved.
According to another aspect of the invention the side plates of the pyramidal horn structure are eliminated as they affect the behavior of the main beam.
The foregoing has outlined rather broadly aspects, features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional aspects, features and advantages of the invention will be described hereinafter. It should be appreciated by those skilled in the art that the disclosure provided herein may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. Persons of skill in the art will realize that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims, and that not all objects attainable by the present invention need be attained in each and every embodiment that falls within the scope of the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a 3-dimensional view of a prior art ridged horn antenna.
FIG. 2 shows a bottom, side and rear view of the prior art ridged horn antenna of FIG. 1 .
FIG. 3 shows the side and edge view of a ridge employed in the prior art ridged horn antenna of FIG. 1 .
FIGS. 4 , 5 , and 6 are charts of the gain, VSWR, and Half Power Beam width versus frequency, respectively, for the prior art antenna of FIG. 1 .
FIGS. 7 , 8 , 9 show the normalized radiation patterns for prior art ridged horn antenna of FIG. 1 for 3, 12, and 17 gHz, respectively.
FIG. 10 is a 3-dimensional view of a preferred embodiment of the ridged horn antenna of the present invention.
FIG. 11 shows an aperture view of a preferred embodiment of the ridged horn antenna of the present invention.
FIG. 12 shows a side view of a preferred embodiment of the ridged horn antenna of the present invention.
FIG. 13 shows a top view of a preferred embodiment of the ridged horn antenna of the present invention.
FIG. 14 shows a side view and edge view of a preferred embodiment of a ridge for the present invention.
FIGS. 15 , and 16 are charts of the gain, and VSWR versus frequency, respectively, for the preferred embodiment of the present invention.
FIGS. 17 , 18 , 19 show the normalized radiation patterns for prior art ridged horn antenna of FIG. 1 for 3, 12, and 17 gHz, respectively.
FIG. 20 shows a comparison between a ridge of the prior art and a ridge of a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A 3-dimensional view of a preferred embodiment of a ridged horn antenna 5000 of the present invention is shown in FIG. 10 . An aperture view is shown in FIG. 11 . The embodiment comprises an upper plate 5100 and a lower plate 5200 that are affixed to a cavity assembly 5001 . Cavity assembly 5001 is preferably rectangular in cross-section and is open at one end. Affixed to upper plate 5100 is an upper ridge 5150 and affixed to lower plate 5200 is a lower ridge 5250 .
A side view of the preferred embodiment of antenna 5000 is shown in FIG. 12 , comprising upper plate 5100 , lower plate 5200 , upper ridge 5150 , lower ridge 5250 , and cavity assembly 5001 . The angle between upper and lower plates 5150 and 5250 is nominally 41.97 degrees in the preferred embodiment as shown in FIG. 12 . In a side 6010 of cavity assembly 5001 is a fitting 6020 , such as a precision type N jack, to receive a coaxial cable (not shown) to deliver RF power to antenna 5000 . The center conductor 6030 of the coaxial feed inserts through a hole in lower ridge 5250 , through the gap 6040 between upper and lower ridges 5250 and 5150 , and terminates in upper ridge 5150 .
Upper plate 5100 , upper ridge 5150 , and cavity assembly 5001 are shown in FIG. 13 , which is a top view of the preferred embodiment of antenna 5000 . Also shown is a tuning tongue 7100 for higher order mode suppression. The dimensions of the tongue are nominally 800 mils long by 620 mils and being 15 mils in thickness, the tongue has a notch centered on the width that is 320 mils by 700 mils deep for this embodiment. Directly behind the tongue is a smaller interior cavity formed in the inner rear wall of cavity assembly 5001 for additional control over the characteristics of the antenna, such as for example reducing the VSWR of the antenna. The dimensions of this interior cavity are 163 mils deep by 800 mils by 500 mils.
Further, extending from the rear 7200 of cavity assembly 5001 is a threaded stud 7300 for centering and mounting antenna 5000 , as well as indexing pins 7400 for alignment. Note, as indicated in FIG. 13 , that upper and lower ridges 5150 and 5250 extend beyond the edges 5175 of upper and lower plates 5100 and 5200 , respectively.
FIG. 14 is a side view and an edge view of a ridge 5150 or 5250 of the present invention. Each ridge exhibits a nominal edge thickness of 0.266 inches and a nominal length of 6.486 inches. The ridge also exhibits a curvature or flare with nominal coordinates in inches as follows:
X 0.249 0.679 1.395 1.750 2.110 2.473 2.841 3.215 3.592 3.983 4.780 Y 1.102 1.268 1.516 1.639 1.748 1.848 1.936 2.007 2.071 2.100 2.117
for coordinates extending to a point where the tangent to the curve is parallel to a plate;
X 5.083 5.399 5.571 5.750 6.047 6.179 6.3 6.423 6.474 6.486 Y 2.112 2.073 2.018 1.943 1.759 1.609 1.426 1.235 1.040 0.838
for coordinates extending to a point where the tangent to the curve is vertical; and
X 6.436 6.342 6.021 Y 0.648 0.515 0.447
for coordinates extending to the plate edge.
FIGS. 15 , and 16 are charts of the gain, and VSWR versus frequency, respectively, for the preferred embodiment of the present invention. Clearly, comparing FIGS. 4 and 15 , and FIGS. 5 and 16 , a smoother gain curve is achieved by the present invention and a substantial improvement in gain is obtained at the highest frequency of operation, without a substantial sacrifice in VSWR.
FIGS. 17 , 18 , 19 show the normalized radiation patterns for the preferred embodiment of the present invention for 3, 12, and 17 gHz, respectively. Comparing these to the corresponding plots for the prior art antenna shown in FIGS. 7 , 8 , and 9 , a clear and substantial improvement in the main lobe is achieved. At 17 gHz the side lobe level has been reduced while the 3 dB beamwidth has been improved making the antenna more suitable for immunity EMC testing.
Shown in FIG. 20 is a comparison of ridge 1150 of the prior art Model 3115 and the ridge 5150 of the preferred embodiment of the present invention. Note that the angle of the prior art flare measured from the horizontal to the plate, φ 1 , is about 13 degrees, whereas for the preferred embodiment, the angle of the flare measured from the horizontal to the plate, φ 2 , is about 21 degrees.
Expressing the dimensions of the preferred embodiment in terms of fractions of a wavelength at the lowest frequency of operation, λ L , in this instance, 1 gHz with λ L =11.811 inches, we have as follows:
the length, L=6.977 inches, of the antenna is about 0.591λ L , compared to L=8.13 inches=0.688λ L for the Model 3115; the aperture width, W=6.949 inches, of the antenna is about 0.588λ L , compared to W=9.63 inches=0.82λ L for the Model 3115; and the aperture height, H=6.036 inches, of the antenna about 0.511λ L , compared to H=6.25 inches=0.53λ L for the Model 3115.
Expressing the dimensions of the preferred embodiment in terms of fractions of a wavelength at the highest frequency of operation, λ H , in this instance, 18 gHz with λ H =0.656 inches, we have as follows:
the length, L=6.977 inches, of the antenna is about 10.63λ H , compared to L=8.13 inches=12.39λ H for the Model 3115; the aperture width, W=6.949 inches, of the antenna is about 10.59λ H , compared to W=9.63 inches=14.68λ H for the Model 3115; and the aperture height, H=6.036 inches, of the antenna is about 9.20λ H , compared to H=6.25 inches=9.52λ H for the Model 3115.
Note that although the angle of the flare formed by upper and lower plates 5150 and 5250 of the preferred embodiment is much greater than the corresponding angle for the Model 3115, the aperture height, H, is about the same for both antennas, yet the antenna length and width has been shortened considerably in the present invention compared to the prior art.
Thus, although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. The invention achieves multiple objectives and because the invention can be used in different applications for different purposes, not every embodiment falling within the scope of the attached claims will achieve every objective.
Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. | The present invention provides apparatus and methods for a ridge horn antenna that exhibits improved directivity and main lobe of the radiation pattern at the high end of the frequency range for which its gain remains usably high, while providing a relatively low VSWR across the frequency range of operation. | 7 |
CROSS REFERENCE TO RELATED DOCUMENTS
[0001] This application claims priority benefit of U.S. provisional patent application No. 60/907,603, filed Apr. 11, 2007 which is hereby incorporated by reference.
COPYRIGHT NOTICE
[0002] A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
[0003] Change detection out in the field for the identification of anomalies in areas of interest is of primary importance in the gathering of information vital to the discovery of changing conditions in the field of view. This type of discovery can presage the ability to move resources into the area to deal with the changing conditions. This type of data-intensive activity is extremely time-intensive and requires highly trained personnel for the greatest effectiveness. Instituting a human-machine interaction for change detection in extremely dense sensor datasets may provide for much greater accuracy, greater efficiency and improved definitions for targets of interest within the dataset.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The above and other objects, features and advantages of the present invention will become more apparent in light of the following detailed description of exemplary embodiments taken in conjunction with the attached drawings, in which:
[0005] FIG. 1 : provides a system block diagram of processing relationships consistent with certain embodiments of the invention.
[0006] FIG. 2 : provides a view of Active Learning with an analyst-in-the-loop consistent with certain embodiments of the invention.
[0007] FIG. 3 : is a view of an analyst-in-the-loop target probability consistent with certain embodiments of the invention.
[0008] FIG. 4 : provides a view of an accuracy comparison for two analysts consistent with certain embodiments of the invention.
[0009] FIG. 5 : is a view of analyst results efficiency consistent with certain embodiments of the invention.
DESCRIPTION OF THE INVENTION
[0010] The pages that follow describe experimental work, presentations and progress reports that disclose currently preferred embodiments consistent with the above-entitled invention. All of these documents form a part of this disclosure and are fully incorporated by reference. This description incorporates many details and specifications that are not intended to limit the scope of protection of any utility patent application which might be filed in the future based upon this provisional application. Rather, it is intended to describe an illustrative example with specific requirements associated with that example. The description that follows should, therefore, only be considered as exemplary of the many possible embodiments and broad scope of the present invention. Those skilled in the art will appreciate the many advantages and variations possible on consideration of the following description.
[0011] Thus, the reader should understand that the present document, while describing commercial embodiments, should not be considered limiting since many variations of the inventions disclosed herein will become evident in light of this discussion. While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail specific embodiments, with the understanding that the present disclosure is to be considered as an example of the principles of the invention and not intended to limit the invention to the specific embodiments shown and described.
[0012] Turning to FIG. 1 , consistent with certain embodiments of the invention the system consists of two major functions, Automated Preprocessing 100 of the received sensor data and Change Detection for identification and classification of areas of interest within the sensor data. The Automated Preprocessing begins by extracting and loading Change Detection features from the server storage media 115 . These features provide the foundation upon which the automated processes rely in processing the incoming sensor data for areas of interest. The Prescreener module then utilizes the feature definitions to define Regions of Interest for further examination 120 . A Classifier module then constructs a list of classified features as those areas that require further analysis and/or classification 125 and forwards this data to the Change Detection process.
[0013] To provide greater efficiency in the detection of pre-defined targets to be located within captured sensor data, a Change Detection (CD) 110 software process and tool is provided. The CD 110 uses a hierarchical registration procedure to align captured sensor data and highlight areas where any one of a set of pre-defined targets may have been emplaced. The CD 110 uses identified disturbances to the surrounding environment as threshold events to capture areas that should be highlighted and presented as cues to an Analyst-in-the-loop. The Analyst may then use the cues, presented as a prioritized list, to achieve much greater efficiencies in the identification of any pre-defined targets embedded within the captured sensor data set 145 .
[0014] The identification of pre-defined targets within a set of data collected from a sensor array may be accomplished with any sensor array and within any collected data set. The CD 110 process is dependent upon the identification of those targets of interest 130 within the collected data set as defined by an expert analyst with deep knowledge of what targets are to be designated as “of interest” 145 . In this manner, the CD 110 process utilizes the expert analyst knowledge of designated targets as the starting basis for training the CD 110 process in recognition of targets within a collected data set 135 .
[0015] Turning to FIG. 2 , consistent with certain embodiments of the invention the Active Learning Flow 200 is the module that utilizes the training and experience of the Analyst-in-the-loop to increase the basis level of region of interest recognition, identification and classification. Having an initial database of targets defined and optimized by an expert analyst 140 allows all analysts to take advantage of an expert's work. In this manner, further target definition and learning is emplaced within the target database as further optimization of the defined target data 140 . This process also mitigates and partially bypasses the analyst learning curve for target identification. Each analyst begins with an expert's knowledge of targets that are to be identified and continues to optimize the database as new targets and categories of targets are recognized and defined.
[0016] The Active Learning Flow 200 module receives the current Basis Selection Labels 205 as an initial identification and classification starting point. This data set is directed as input to a logistic regression classifier module 210 that provides a list of all recognized and labeled targets within a region of interest as well as a list of unlabeled suspected targets that meet some or all of the classification parameters but do not fit into an established classification category. The logistic regression classifier module 210 also receives as input any new labels for unlabeled suspected targets that have been provided by the Analyst-in-the-loop 220 . The system server then reconciles the newly added labels with the incoming unlabeled suspected targets in an information gain for all unlabeled data 215 , and presents this data to the Analyst. In an iterative step, the Active Learning Flow module 200 compares the labeled data, unlabeled data, and classification parameters to determine what, if any, substantial new information remains in the incoming data 225 . If there are newly characterized targets within the remaining data, these targets are presented to the Analyst for labeling, if there are newly characterized targets that are sufficiently within the parameters of previously defined labels or classification parameters, the Active Learning Flow 200 module labels these targets and presents them to the Analyst for concurrence. Once all new information within the remaining data has been processed and there are no further data objects that might be considered for labeling as being targets or of interest, the Basis Selection Labels 205 data tables are updated 235 to reflect the new level of data identification and understanding.
[0017] The CD 110 process can be utilized with any target that can be defined as “of interest” within any set of collected data from any deployed sensor array. In an embodiment of interest, the deployed sensor array is an array that collects visual data, from both visible light and infrared spectra. The targets of interest within this same embodiment are Improvised Explosive Devices (IEDs) and analysts have established a pre-identified set of targets based upon changes in a visual environment. Although this embodiment has been deployed and tested the invention herein described is in no way limited to just this type of sensor array, or the targets defined for this embodiment. An Analyst may use the most recent Basis Selection Labels 205 data tables to perform a simple Target/No Target analysis process 230 to provide feedback and concurrence with the most recent data tables. This step provides training for less experienced analysts and insures the quality and integrity of the labeled data within the Basis Selection Labels 205 stored data tables. Other embodiments of interest could include medical, financial, security, intelligence and process control sensor arrays with targets of interest comprising anomalous objects specific to each of these industry segments. Thus, the described invention is in no way limited to the single embodiment of interest that is further discussed herein below.
[0018] Turning to FIG. 3 , consistent with certain embodiments of the invention, this diagram presents a representation of the sorted probability of unlabeled data being associated with a target. For a data set consistent with an embodiment of the invention the system has provided a list of probable labeled targets from a set of hundreds of data points that may represent clutter, along with their probabilities relative to clutter. This data is presented to an Analyst in probability order with the highest probability labeled data presented first, lowest probability labeled data presented last.
[0019] For this embodiment of interest, the CD 110 process requires visible light data (monochromatic) and infrared data (MWIR) collected for the same target area over two separate collection periods (day 1 and day 2). The data from both mono and MWIR passes requires coarse registration (within approximately 10 pixels across the images). The registration solves for differences in parameters such as sensor height and sensor angle in order to align all captured images. This coarse scale registration assures that a fine scale (pixel level) registration can be performed during feature extraction via a simple horizontal and vertical translation. The pixel level registration is accomplished by finding the local translation that produces the maximum correlation between day 1 and day 2 imagery data. The coarse level registration is required across all four data sets, mono day 1, mono day 2, MWIR day 1 and MWIR day 2. Because of the difference in resolution between the sensors, the MWIR data is up-sampled prior to the registration procedure so that all four image sets are the same resolution.
[0020] Suitable key points in all sets of imagery are identified, such as the locations represented by the key points. The key points are used in an elastic registration technique to coarsely register the images. Once the four sets of images are registered with each other, features can be extracted based on the changes between the mono day 1 and day 2 and the MWIR day 1 and day 2 captured data sets. Change detection 110 features between mono and MWIR data sets can then also be associated with each other because of the initial co-registration.
[0021] For each of the image sets (mono day 1 and day 2, and MWIR day 1 and day 2) the system applies an initial detector to identify regions of interest (ROI). The goal of defining the ROIs is to associate the extracted CD 110 features which are related to a particular physical disturbance in the collected data image. This association reduces the false alarms (features that are selected but that do not, upon subsequent view by an analyst, correspond to targets) to a manageable size and removes ambiguity between features and the objects in the collected data images.
[0022] A target detection process is applied to the imagery to extract targets by element-wise multiplying the feature plots of the between day mono and MWIR images. The resulting plot represents areas where there are day 1 to day 2 changes for both the mono and the MWIR imagery. A threshold may then be applied based upon a desired probability of target detection versus the number of false alarms. The threshold is applied to the captured image data and determines the total number of ROIs and the possibility of missing actual targets, with a threshold set to achieve a very high probability of detection of ROIs containing targets.
[0023] Once the detector process selects a set of ROIs, the original features for those ROIs are assembled into a feature vector for each ROI. A feature vector is created using the maximum mono Mean Square Error (MSE) in the ROI, the maximum MWIR MSE in the ROI, the distance of the ROI centroid from a road, the area of the ROI, the eccentricity of the ROI shape, and the orientation, relative to the axes, of the ROI shape. The last three features help exclude ROIs associated with shadow artifacts which account for a majority of false alarms.
[0024] Turning to FIG. 4 , the feature vectors are then prioritized based upon the probability that the ROI may contain a target of interest, based upon the learned classification for targets previously identified. This prioritized list of ROI feature vectors is then presented to analysts viewing the captured imagery. In this manner, each analyst is presented with high probability of target ROIs, minimizing the amount of time an analyst must view non-productive portions of the imagery and maximizing target identification versus false alarms. In a certain embodiment the presentation of priority classified data and the automated pre-classification of targets within regions of interest improves the accuracy of the target identification and labeling of real targets in the field. This figure illustrates an improvement in the accuracy for two different analyses. The computer server was presented with sensor data that had been pre-classified for regions of interest and then attempted to locate and label a set of real targets that were placed in known positions in the field. A second set of sensor data with targets placed in known positions was then presented to the computer server, but this time with an analyst assisting in the identification and labeling of targets. The results data is graphed as the number of targets located (Number of FA) versus the Percentage Detected (Pd) accurately. For each analyst there was a marked improvement in the accuracy of targets identified and labeled within the data sets presented.
[0025] Turning to FIG. 5 , active learning is an integral portion of utilizing analyst feedback to improve target and ROI identification in an iterative fashion. Not all unlabeled data are equally informative for reducing the uncertainty of the classifier weights for the feature vectors chosen. A classifier process is trained based on labels provided by an analyst for feature vectors chosen via basis selection with the active learning objective function being calculated for all remaining unlabeled data. The goal is to select the unlabeled feature vector to maximize the mutual information between the unknown label for a new feature and the classifier weights to be sought. By labeling the most informative data first, the classifier can be training with the fewest number of labeled data points. As shown in the exemplary figure, two different analysts are presented with a data set in which each analyst must locate a plurality of targets with known positions but without the assistance of the CD 110 server. Each analyst is then presented with a second data set containing known targets and tasked with locating all targets with the assistance of the CD 110 server. As shown in the exemplary figure, when operating as an Analyst-in-the-loop each analyst improved markedly in both the number of targets identified and labeled (percent detected) and the amount of time required to locate the targets that were identified and labeled. In a plurality of trials with a number of analysts this improvement is in the range of 300 to 400 percent over target identification and labeling by an analyst alone. This maximizes the training effort and reduces the cost in terms of time and data that must be collected for training.
[0026] Once the ROIs and possible target information is presented to an analyst, the analyst will view the captured imagery, scanning back and forth between day 1 and day 2 imagery. The analyst will provide feedback to the learning database in the form of reinforcement verification for targets that are positively identified, negative verification for those possible identified targets that are false alarms, and identification data for objects that are new target types. All ROIs are labeled in order of probability to provide positive verification for targets within the captured imagery data and to maximize the probability of detection per unit of analyst time.
[0027] In the disclosed embodiment, the process disclosed above prior to presenting this list to an analyst has resulted in performance improvements in the 300 to 400 percent range for test data supplied. This performance improvement can be partially ascribed to the advantage of an analyst having prioritized and pre-screened ROIs presented for labeling, thus reducing the amount of imagery each analyst must review. In addition, the prioritization of ROIs allows analysts to view the ROIs most likely to contain targets at the beginning of a review cycle when an analyst is more alert. At the same time, the disclosed method is more efficient at allowing an analyst to operate on an identified list of ROIs in significantly less time than operations performed without such a prioritized list. This results not only in the positive identification of a larger percentage of true targets in a shorter time period, but also contributes to a huge reduction in false alarms.
[0028] While certain illustrative embodiments have been described, it is evident that many alternatives, modifications, permutations and variations will become apparent to those skilled in the art in light of the description. | The Analyst Cueing method addresses the issues of locating desired targets of interest from among very large datasets in a timely and efficient manner. The combination of computer aided methods for classifying targets and cueing a prioritized list for an analyst produces a robust system for generalized human-guided data mining. Incorporating analyst feedback adaptively trains the computerized portion of the system in the identification and labeling of targets and regions of interest. This system dramatically improves analyst efficiency and effectiveness in processing data captured from a wide range of deployed sensor types. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
In one of its aspects, the present invention relates to a fastener assembly with a peripheral seal. More particularly, the present invention relates to a fastener assembly which may advantageously be molded into a cushion and used to secure a cover material to the cushion. In another of its aspects, the present invention relates to a process for producing a fastener assembly. In yet another of its aspects, the present invention relates to a cushion comprising a fastener assembly.
2. Description of the Prior Art
In the art of adhering or securing cover materials to cushion elements, it is known to utilize a mechanical fastener assembly to adhere a cover material to a cushion element.
One particular class of cushion elements comprises isocyanate-based polymer foams. Isocyanate-based polymer foams are known in the art. Generally, those of skill in the art understand isocyanate-based polymer foams to be polyurethane foams, polyurea foams, polyisocyanurate foams and mixtures thereof.
It is also known in the art to produce isocyanate-based polymer foams by a variety of techniques. Indeed, one of the advantages of isocyanate-based polymers compared to other polymer systems is that polymerization and foaming can occur in situ. This results in the ability to mold the polymer while it is forming and expanding.
One of the conventional ways to produce an isocyanate-based polymer foam, such as a polyurethane foam, is known as the "one-shot" technique. In this technique, the isocyanate, a suitable polyol, a catalyst, water (which acts as an indirect, reactive blowing agent and can optionally be supplemented with one or more blowing agents) and other additives are mixed together at once in a suitable mixer to produce a liquid foamable composition. The liquid foamable composition and is then expanded and/or molded to produce polyurethane foam. Generally, if one were to produce a polyurea, the polyol would be replaced with a suitable polyamine. A polyisocyanurate may result from cyclotrimerization of the isocyanate component. Urethane-modified polyurea foam or polyisocyanurate foam are known in the art. In either scenario, the reactants would be intimately mixed very quickly using a suitable mixer.
When it is desired to utilize a mechanical fastener to adhere a cover material to the isocyanate-based polymer foam, it is known to place the mechanical fastener in the mold such that it is molded into the finished foam product. Generally, a conventional mechanical fastener comprises a touch fastening surface. As used throughout this specification, the term "touch fastening surface" is intended to mean a surface which will adhere to a complementary surface on the cover material to be adhered to the cushion element. Practically, the touch fastening surface has taken the form of one half of a "hook and loop" fastener system. This type of touch fastening surface has gained commercially popularity due to its reliability and separability after initial adhesion. In other words the touch fastening surface comprises a plurality of hook elements and the cover material comprises a plurality of loop elements, or vice versa, such that the hook elements and loop elements mechanically engage one another when pressed into contact. Generally, it has been preferred to have the hook elements on the mechanical fastener molded in the cushion element and the loop elements on the cover material to be adhered to the cushion element. Alternatively, the touch fastening surface may be an adhesive which, upon contact, will adhere to an appropriate cover material.
Conventionally, the mechanical fastener is placed in the mold such that the touch fastening surface is flush against a surface of the mold (usually the mold surface is provided with a trench for receiving the touch fastening surface of the mechanical fastener)--i.e. such that the touch fastening surface is exposed in the finished foam product. When utilizing such a mechanical fastener in a mold for producing an isocyanate-based polymer foam, specific care must be taken to avoid fouling of the touch fastening surface of the mechanical fastener with the liquid foamable composition which is dispensed into the mold. Fouling of the touch fastening surface can occur as a result of the liquid nature of the foamable composition, together with the generally above-ambient pressure conditions within the mold. Specifically, these pressure conditions within the mold tend to drive the liquid foamable composition into any available cracks and crevices which may be present between the touch fastening surface and the mold surface.
Thus, much attention in the prior art has been devoted to development of mechanical fasteners which are designed to obviate or mitigate fouling of the touch fastening surface by ingress of the liquid foamable composition.
The conventional approach has been to place a temporary, removable tape/film over the touch fastening surface of the mechanical fastener. During polymerization and expansion of the liquid foamable composition, the tape/film inhibits fouling of the touch fastening surface. After production of the foam cushion element with the mechanical fastener molded therein, the tape/film may then be removed. This type of mechanical fastener is still the predominant system in current commercial use. Notwithstaning this, the system is disadvantageous since the cost of the mechanical fastener is increased by the need for the tape and significant labor expense is incurred in removal of the tape/film after production of the foam cushion element.
The prior art has attempted to overcome these disadvantages using a number of different approaches.
U.S. Pat. No. 4,784,890 Black!, the contents of which are hereby incorporated by reference, teaches a tapeless fastener assembly with a peripheral temporary attachment layer. Specifically, the elongate fastener assembly taught in this patent comprises a pair of longitudinally extending strips containing ferromagnetic particles which, when placed in the vicinity of magnets in the mold, purportedly seal the hook elements in the fastener assembly from ingress of liquid foamable composition. Generally, the temporary attachment layer is a binder containing iron particles, the binder coated on the longitudinal edges of the fastener assembly. The fastener assembly may contain a seal at the ends thereof. In one embodiment, this end seal contains ferromagnetic particles and is ultrasonically staked to the backing layer of the fastener, thereby necessitating: (i) the use of additional magnets in the mold (i.e. retooling), and/or (ii) significant material and labor cost to place two specially designed end seals for each fastener assembly.
U.S. Pat. No. 4,842,916 Ogawa et al.!, the contents of which are hereby incorporated by reference, teaches a tapeless fastener assembly. Specifically, the elongate fastener assembly taught in this patent comprises a pair of longitudinally extending strips containing a sealing member. The sealing member can be fibrous, resinous or a foam. This fastener assembly is disadvantageous since there is no disclosure or suggestion of a provision for sealing the ends of the assembly. The present inventors have determined that failure to seal the ends of the fastener assembly results in significant fouling of the touch fastening surface.
U.S. Pat. No. 5,500,268 Billarant!, the contents of which are hereby incorporated by reference, teaches a tapeless fastener assembly with magnetic side and end seals. The side seals comprise a flexible sheeting material containing magnetically attractable powder. The fastener assembly comprises a plurality of hook members on the fastening surface. The end seals are simply a small portion of loop material located at each end of the fastening surface. This fastener assembly is disadvantageous for a number of reasons. First, the use of magnetically attractable side seals necessitates the use of additional magnets in the mold (i.e. retooling). Second, the ends seals must be very carefully placed since reliance is placed on the "hook and loop" engagement provide a seal against ingress of liquid foamable composition. Third, the combination of side seals and end seals does not provide a complete, continuous seal around the periphery of the hook members on the fastening surface. Fourth, the end seals are generally deficient since they are designed to be located in the trench in the mold (FIG. 5), while the seals are intended to be located out of the trench and against the mold surface. Fifth, the use of end seals which comprise hook members facilitates fouling of the touch fastening surface due to the difficulty in compressing the hook (or loop) members to provide an adequate seal.
See also the following references:
U.S. Pat. No. 4,470,857 Casalou!;
U.S. Pat. No. 4,563,380 Black et al!;
U.S. Pat. No. 4,617,214 Billarant!;
U.S. Pat. No. 4,693,921 Billarant!;
U.S. Pat. No. 4,710,414 Northrup et al.!;
U.S. Pat. No. 4,726,975 Hatch!;
U.S. Pat. No. 4,802,939 Billarant!;
U.S. Pat. No. 4,814,036 Hatch!;
U.S. Pat. No. 4,933,035 Billarant!; and
U.S. Pat. No. 5,171,395 Gilcreast!;
the contents of each of which are hereby incorporated by reference.
Despite all of these attempts in the prior art to improve mechanical fasteners, the result is that the mechanical fastener of this type in widespread commercial use is the one comprising a temporary, manually removable tape over the touch fastening surface of the mechanical fastener.
It would be desirable to have a mechanical fastener which reduces or overcomes one or more of the above-identified disadvantages of the prior art. It would also be desirable if such an improved mechanical fastener could be readily produced and used in existing molds.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a novel mechanical fastener which obviates or mitigates one or more of the above-mentioned disadvantages of the prior art.
It is another object to provide a novel process for producing a mechanical fastener.
It is yet another object of the prior art to provide a novel cushion comprising a mechanical fastener.
Accordingly, in one of its aspects, the present invention provides a fastener assembly capable of being molded into a cushion, the fastener assembly comprising:
(i) a backing layer and (ii) a fastening layer opposed to one another, the backing layer comprising anchor means to secure the fastener assembly to the cushion, the fastening layer comprising a touch fastening surface spaced inwardly from the marginal edges of the fastening layer to define a peripheral margin around the fastening layer, and (iii) a foam seal disposed on the peripheral margin, the foam seal having an Indentation Force Deflection, when measured pursuant to ASTM D3574-95, in the range of from about 10 to about 1000 pounds.force.
In another of its aspects, the present invention provides, a process for producing a fastener assembly comprising the steps of:
(i) providing an elongate fastening layer comprising a plurality of hook members disposed substantially orthogonal to and spaced inwardly from the longitudinal marginal edges of the fastening layer to define a pair of longitudinal margins substantially free of the hook members;
(ii) removing at least two sections of the plurality of hook members, each section being substantially transverse to the longitudinal marginal edges, to define a peripheral margin around the touch fastening surface, the peripheral margin being substantially free of touch fastening surface;
(iii) adhering a foam seal to the peripheral margin.
In yet another of its aspects, the present invention provides a cushion comprising a substrate body and a fastener assembly molded into a surface of the cushion, the fastener assembly comprising:
(i) a backing layer and (ii) a fastening layer opposed to one another, the backing layer comprising anchor means to secure the fastener assembly to the cushion, the fastening layer comprising a touch fastening surface spaced inwardly from the marginal edges of the fastening layer to define a peripheral margin around the fastening layer, and (iii) a foam seal disposed on the peripheral margin, the foam seal having an Indentation Force Deflection, when measured pursuant to ASTM D3574-95, in the range of from about 10 to about 1000 pounds.force.
Thus, the present inventors have discovered an improved fastener assembly having a foam seal disposed along a peripheral margin of the fastening layer, the foam seal having an Indentation Force Deflection (IFD), when measured pursuant to ASTM D3574-95, in the range of from about 10 to about 1000 pounds.force. Specifically the fastening layer has a touch fastening surface spaced inwardly from all marginal edges of the fastening layer to define a peripheral margin substantially completely free of touch fastening surface. Provision of such a foam seal having the above-mentioned IFD along this peripheral margin results in a fastener assembly which significantly eliminates most (if not all) fouling of the touch fastening surface during molding into the cushion.
Preferably, the foam seal is substantially non-magnetically attractable (i.e. the foam is magnetically inert). In this embodiment, if a magnetically attractable element is used to facilitate positioning of the fastener assembly in sealing engagement with the mold, it is preferred that the magnetically attractable element not be disposed in the seal portion of the fastener assembly (i.e. in contrast to the approach used by Black and Bilarant '268 discussed hereinabove). Specifically, it has been discovered that, when a magnetically attractable member is disposed in the present fastener assembly independent of the foam seal (e.g. incorporated in one or both the backing layer and the fastening layer, or disposed between the backing layer and the fastening layer and the like), the performance of the foam seal in preventing fouling of the touch fastening surface is improved. This is believed to occur as a result of: (i) the compressive force being applied across substantially the entire thickness of the seal; (ii) avoiding use of metal in the seal to provide a low firmness, compressible seal, (iii) the ability to utilize the body of the fastener assembly to compress the foam seal against the mold surface producing an improved seal while eliminating the possibility that magnetic forces will separate the seal from the fastener assembly (e.g. as a result of pulling on a magnetically attractable seal). Thus, in one embodiment, the magnetically attractable member may be a magnetically attractable metal layer disposed between the backing layer and the fastening layer. In another embodiment, the magnetically attractable member may be a magnetically attractable metal disposed in the fastening layer. In this embodiment, the magnetically attractable metal, inter alia, may be in the form of particulate metal molded into the fastening layer or it may be in the form of a wire mold in or otherwise affixed to the fastening layer. In yet another embodiment, the magnetically attractable member comprises a magnetically attractable metal disposed in the backing layer. Thus, if one considers the foam seal to have a mold abutment surface and a fastening layer abutment surface, it is preferred the magnetically attractable metal (if present) be disposed away from and not form part of the foam seal. The result of this feature is that, when the present fastener assembly is placed in the vicinity of one or more magnets appropriately located in the mold, substantially the entire body of the fastener assembly compresses the foam seal to the mold thereby providing an improved seal with the mold (i.e. compared with urging the seal only against the mold).
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will be described with reference to the accompanying drawings, wherein like numerals refer to like parts and in which:
FIG. 1 illustrates a perspective view of a portion of an embodiment of the present fastener assembly;
FIG. 2 illustrates a perspective view of a portion of another embodiment of the present fastener assembly;
FIG. 3A is a sectional view along line III--III of FIG. 2;
FIG. 3B illustrates the fastener assembly illustrated FIG. 3A urged against a surface of a mold;
FIG. 4A is a sectional view of a fastener assembly modified from that illustrated in FIG. 3A;
FIG. 4B illustrates the fastener assembly illustrated FIG. 4A urged against a surface of a mold;
FIGS. 5-7 illustrate a schematic of the fastener assembly illustrated in FIG. 2 at various points along a process embodiment for production thereof; and
FIGS. 8-12 illustrate a schematic of the fastener assembly illustrated in FIG. 1 at various points along another process embodiment for production thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIG. 1, there is illustrated a fastener assembly 10. Fastener assembly 10 comprises a backing layer 15 and a fastening layer 20. Fastening layer 20 comprises a touch fastening surface 25 which consists of a plurality of hook members 30 spaced inwardly from all marginal edges of fastening layer 20. Spacing in of hook members 30 in this manner defines a peripheral margin on fastening surface 25. Disposed on this peripheral margin are a pair of longitudinal foam seals 35,40. An end foam seal 45 is provided in the portion of the peripheral margin between longitudinal foams seals 35,40. The other end of fastener assembly 10 (not shown) comprises a similar foam end seal.
With reference to FIG. 2, there is illustrated a fastener assembly 110. Fastener assembly 110 comprises a backing layer 115 and a fastening layer 120. Fastening layer 120 comprises a touch fastening surface 125 which consists of a plurality of hook members 130 spaced inwardly from all marginal edges of fastening layer 120. Spacing in of hook members 130 in this manner defines a peripheral margin on fastening layer 120. Disposed on this peripheral margin is an integral foam seal 135 which is disposed along the entire periphery of fastening layer 120, including the other end (not shown) of fastening layer 120.
With reference to FIG. 3A, it can be seen that backing layer 115 of fastener assembly 110 comprises a plurality of loop members 150. Further, interposed between backing layer 115 and fastening layer 120 is a magnetically attractable strip 155.
With reference to FIG. 3B, fastener assembly 110 illustrated in FIGS. 2 and 3A is illustrated in use. Specifically, fastener assembly 110 is placed against a mold surface 160 such that foam seal 135 contacts mold surface 160. As illustrated, mold surface 160 further comprises a trench 165 adapted and dimensioned to receive hook members 130 of fastening layer 120. Trench 165 comprises a magnet 170 positioned below a point corresponding generally to where magnetically attractable strip 155 will be located. As illustrated, magnet 170 attracts magnetically attractable strip 155 which serves to urge the entire surface of fastening layer 120 against mold surface 160. This interaction results in compression of foam seal 135 to provide a highly desirable seal which substantially reduces and, in certain cases, eliminates ingress of foamable composition into trench 165 and thereafter to touch fastening surface 125. Thus, foam seal 135 is compress along the periphery of trench 165 rather than having a portion thereof located in trench 165.
A particularly preferred aspect of the embodiment illustrated in FIG. 3B is compression of foam seal 135 as a result of urging of substantially the entire surface of fastening layer 120 toward mold surface 160. This approach is more preferred to utilizing magnetically attractable particles in foam seal 135. Thus, it has been discovered that a particularly advantageous seal is formed when foam seal 135 has an Indentation Force Deflection (IFD) when measured pursuant to ASTM D3475-95, in the range of from about 10 to about 1,000, preferably from about 10 to about 500, more preferably from about 10 to about 250, most preferably from about 10 to about 100, pounds.force. The precise nature of foam seal 135 is not particularly restricted provided that it have the requisite IFD. Preferably, foam seal 135 is comprised of polyurethane foam. The precise nature of useful polyurethane foams is not particularly restricted--see "Flexible Polyurethane Foams" by Herrington et al. (1991), the contents of which are hereby incorporated by reference. A particularly useful polyurethane foam is commercially available from Woodbridge Foam Corporation under the tradename ES150.
With reference to FIGS. 4A and 4B, there is illustrated a fastener assembly slightly modified from the one illustrated in FIGS. 3A and 3B. Specifically, foam seal 135A in FIGS. 4A and 4B has a height greater then hook members 130 on fastening layer 120. The result of this is mold surface 160A is not required to have a trench (similar to trench 165 in FIG. 3B) to receive hook members 130 of fastening layer 120. Otherwise, the fastener assembly illustrated in FIGS. 4A and 4B can be used in substantially the same manner as the one illustrated in FIGS. 3A and 3B.
Thus, once the fastener assembly is located in and urged against the mold surface, a liquid foamable composition may be dispensed into the mold and expanded to produce a cushion comprising a substrate body having a surface comprising the present fastener assembly molded therein. A particularly advantageous feature of the present fastener assembly is that the foam seal disposed along the periphery of the fastening layer facilitates adhesion of the fastener assembly to the substrate body of the cushion by "locking in" the foamable composition as it expands to produce the substrate body of the final cushion product. This feature reduces product failures where the fastener assembly is not properly secured to the substrate body.
The seal against ingress of liquid foamable composition to touch fastening surface of the fastening layer is achieved, at least in part, by the provision of a peripheral margin on the fastening layer defined by spacing end of the touch fastening surface from the marginal edges of the fastening layer. This facilitates provision of a continuous seal around the periphery of the fastening layer which mitigates or obviates fouling of the touch fastening surface due to ingress of the liquid foamable composition.
The precise nature of the backing layer, the fastening layer, the touch fastening surface and the magnetically attractable strip (if present) is not particularly restricted--see, for example the various United States patent references referred to above and incorporated herein by reference.
In a preferred embodiment of the present fastener assembly, various elements may be integral. Thus, for example, the backing layer and the fastening layer may be integrally formed such that the anchor means in the backing layer can be a plurality of integral loops, mushrooms and the like. Alternatively, the backing layer and the fastening layer may be integrally formed such that the anchor means in the backing layer can be a magnetically attractable element conformed to facilitate engagement of the fastener assembly to the cushion. Of course, the backing layer may be an independent element such as a fibrous or non-fibrous material. Non-limiting examples of fibrous materials include at least one member selected from the group consisting essentially of glass fibres (e.g. in the form of a cloth or a mat, chopped or unchopped, such as Nico 754 1 oz/ft 2 ), polyester fibres, polyolefin fibres (e.g. polyethylene and polypropylene), Kevlar fibres, polyamides fibres (e.g. nylon), cellulose fibres (e.g. burlap), carbon fibres, cloth materials such spun bound polyesters (e.g. Lutravil 1DH7210B/LDVT222 and Freudenberg PTLD585G/PTLD600B), nylon and paper (e.g. Kraft #60). For certain such fibrous materials (e.g. paper), the anchor means may be integral in the fibrous material. It will be appreciated that the fibrous reinforcing layer may be woven or non-woven. Non-limiting examples of a non-fibrous materials comprise at least one member selected from the group consisting essentially of thermosets (e.g. polyurethanes, polyesters and epoxies), metals such as aluminum foil, polycarbonates (e.g. Lexan and Dow Calibre), polycarbonate/ABS alloys (e.g. Dow Pulse), ABS terpolymers (e.g. Royalite 59 and Dow Magnum), polyester terphthalate (PET), vinyl, styrene maleic anhydride (e.g. Arco Dylark), and fibreglass reinforced polypropylene (e.g. Azdel). If such fibrous materials are used in the backing layer, it may be appropriate, in certain cases, to modify the materials to comprise anchor means to facilitate engagement of the fastener assembly to the cushion. It will be appreciated that many non-fibrous materials may themselves be reinforced with fibrous materials and thus, the backing layer may be a combination of fibrous and non-fibrous materials, either mixed or composite in construction.
With reference to FIGS. 5-7, a preferred process for the production of fastener assembly 110 illustrated in FIGS. 2, 3A and 3B will now be discussed. Initially, a supply of foam having a thickness equal to that desired for foam seal 135 is obtained. The width of this foam feedstock should be substantially the same as the width of fastener assembly 110. This foam feedstock is fed to a die cutting station resulting in the production of die cut foam 200. Die cut foam 200 comprises longitudinal foam elements 205 and transverse foam elements 210. The provision of elements 205,210 defines a plurality of die cut openings 215. The dimensions of die cut opening 215 are preselected such that they correspond to the dimensions of the touch fastening surface in fastener assembly 110 which is to be produced.
With reference to FIG. 6, there is illustrated a fastening layer 120. Fastening layer 120 comprises a pair of longitudinal margins 122,124 and a pair of transverse margins 126,128. Fastening layer 120 further comprises touch fastening surface 125 as discussed hereinabove. As illustrated in FIG. 6, touch fastening surface 125 is spaced inwardly from all marginal edges of fastening layer 120.
Practically, fastening layer 120 illustrated in FIG. 6 may be produced by starting with a feed material comprising touch fastening surface disposed on the entire surface and thereafter removing selected portions of touch fastening surface 125 to define longitudinal margins 122,124 and transverse margins 126,128. Alternatively, it is possible to produce fastening layer 120 with longitudinal margins 122,124 intact and thereafter selectively remove portions of touch fastening surface 125 to define transverse margins 126,128. In either case, removal of selected portions of touch fastening surface 125 can be achieved by any convenient means. For example, if touch fastening surface 125 comprises a plurality of hook members, the hook members may be selectively removed by one or more of cutting, stamping, grinding, sanding and melting operations.
At this point, die cut foam 200 is positioned over fastening layer 120 such that elements 205,210 of die cut foam 200 are in alignment with longitudinal margins 122,124 and transverse margins 126,128, respectively. Die cut foam 200 is then adhered to fastening layer 120 using any convenient means. For example, die cut foam 200 may be adhered to fastening layer 120 by a suitable adhesive such as contact cement, hot melt adhesive, glue and the like.
Once die cut foam 200 has been adhered to fastening layer 120, a length of fastener assembly 110 is produced--see FIG. 7. At this point, individual fastener assemblies may be produced by cutting the overall length of fastener assembly 110 along lines 220,225. Such cutting can be achieved by conventional means.
Although not illustrated in FIGS. 5-7, backing layer 115 may be adhered to fastening layer 120 prior to or after (preferably prior to) adhesion of die cut foam 200 to fastener assembly 120.
The process described with reference to FIGS. 5-7 is particularly advantageous for entities who manufacture such fastener assemblies. The principal reason for this is that the foam die cut operation and fastening layer stamping or other similar operation which selectively removes a portion of the touch fastening surface may conveniently and conventionally be conducted in the same production line together with the adhesion and cutting operations.
With reference to FIGS. 8-12, the production of fastener assembly 10 will now be described.
A pair of longitudinal foam strips 35,40 may be obtained by any conventional means--see FIG. 8.
With reference to FIG. 9, fastening layer 20 is provided and comprises a pair of longitudinal margins 22,24. Fastening layer 20 further comprises touch fastening surface 25 which is spaced inwardly from the marginal edges of fastening layer 20 thereby defining longitudinal margins 22,24. As will be clear to those of skill in the art, longitudinal margins 22,24 are free of touch fastening surface 25. Fastening layer 20 with the provision of longitudinal margins 22,24 may be obtained as discussed above with respect to fastening layer 120 (FIGS. 5-7). Longitudinal foam strips 35,40 are adhered to longitudinal margins 22,24 of fastening layer 20, respectively. The manner by which adhesion is effected is not particularly restricted--see the foregoing discussion with respect to FIGS. 5-7. This results in production of a fastening layer comprising longitudinal foam seals 35 and 40 disposed at the longitudinal margins of fastening layer 20--see FIG. 10. As is evident, touch fastening surface 25 is spaced in from foam seals 35,40 the longitudinal margins of fastening layer 20.
With reference to FIG. 11, transverse portions 26 are provided in fastening layer 20 by selective removal of portions of touch fastening surface 25. The removal of touch fastening surface 25 at desired locations may be effected as discussed hereinabove with reference to FIGS. 5-7.
With reference to FIG. 12, a pair of foam seals 27,28 are adhered to portions 26 of fastening layer 20. Adhesion of foam seals 27,28 may be effected as discussed hereinabove. The results of this is an overall length of fastening assembly 10. Individual fastening assemblies may be obtained by cutting the overall length of fastener assembly 10 at lines 230,235. Such cutting can be effected in any conventional manner.
The process described with reference to FIGS. 8-12 is particularly advantageous since it allows the foam manufacturer to predetermine and select the overall length of each fastening assembly. Thus, the foam manufacturer may obtain fastening layer 20 as illustrated in FIG. 10 in bulk form and effect the process steps described with reference to FIGS. 11 and 12 to customize the length of each fastener assembly.
Again, fastening layer 20 may contain backing layer 15 prior to or after adhesion of the foam seals.
As will be appreciated by those of skill in the art, many variations of the disclosed process are possible without deviating from the spirit and substance thereof. Accordingly, while the invention has been described with reference to illustrative embodiments, the description is not intended to be construed in a limiting sense. Various modifications of the illustrative embodiments as well as other embodiments of the invention will be apparent to persons skilled in the art upon reference to this description. For example, those of skill in the art will be readily able to employ the illustrative embodiments in either a bulk production operation or a die cut production operation. It is therefore contemplated that the appended claims will cover any such modifications or embodiments. | A fastener assembly capable of being molded into a cushion, the fastener assembly comprising: (i) a backing layer and (ii) a fastening layer opposed to one another, the backing layer comprising anchor means to secure the fastener assembly to the cushion, the fastening layer comprising a touch fastening surface spaced inwardly from the marginal edges of the fastening layer to define a peripheral margin around the fastening layer, and (iii) a foam seal disposed on the peripheral margin, the foam seal having an Indentation Force Deflection, when measured pursuant to ASTM D3574-95, in the range of from about 10 to about 1000 pounds.force. A process for producing the fastener assembly and a cushion describing the fastener assembly are also disclosed. | 8 |
BACKGROUND OF THE INTENTION
The invention is concerned with a procedure for the correction of error in regard to speed related measurement values, in particular, the thickness of a fiber band in a textile machine, more particularly, in a stretch works such as a drawframe.
DE 44 41 067 concerns a controlled stretch works for fiber bands with a feed element for a plurality of incoming fiber bands. In this case, there is available a delay mechanism, a drive system, and a control or regulating means for the drive system. The control, or regulation, reacts to a measurement signal that is sent by the feed element to change the delay of the fiber band by the drive system, so that weight variances in the feed fiber band can be corrected. The regulated stretch works should make possible an improved tendency toward uniformity of the fiber bands, especially by a change in the speed of the feed delivery system by use of braking and acceleration.
The measurement signal of the feed element should be made to conform to and depend on the operating conditions to compensate for changes to the measurements caused by the operating conditions. The state of the technology proceeds from the standpoint of correcting the measurement signal from the feed element on the basis of the output speed (see in said Patent Column 2, lines 52 to 54). This output speed is, however, determined at the exit rolls at the end of the stretchworks arrangement (relative to the calender rolls behind the band receiving hopper.) This approach to speed measurement arises from the conventional concept of the present practice. On the feeler rolls, the speed of the fiber band cannot be determined, because first, delay adjustments are made as part of the control, and second, the feeler roll pair are mechanically interlocked with the delay roll pair. This left only the conclusion to be made that the speed of the fiber band had to be measured at the exit end of the stretch works.
So, from the values of the output speed and the values of the delay, the intake feed speed of the fiber band was then determined by calculation.
This former method of thinking was based on the idea that at the feed entry, speed changes caused by regulation were not available for a measuring instrument. That is, the entry speed as well as the exit speed were assumed to remain equal.
This assumption did not consider the actual available speed changes and the errors which arose therefrom. The use of the delivery speed in the correction which is proposed by the previous state of the technology cannot find support in the actual factual situation. Doing so, leads to the point that an error in the incoming band can be as much as ±25% of the thickness. For instance, at an error of 25%, a rotational speed change of 33% relative to the nominal delay can occur. The use of the exit speed according to the state of the technology again is not supported by the actual body of facts. That described correction process is thus not adaptable to a modern stretch works.
The measurement element is a measuring instrument which actually touches the fiber material. In the spinning world, such measurement elements are known as "feeler rolls", or a feeler probe. A characteristic of the measuring instrument is that a means of sensing, for instance a pivotable roll in a touch roll pair, or a movable probe of a conical sensing probe, touches the moving fiber material. The sensing means is pressed with a specified pressure against the fiber material. The back-thrust from the material is transduced into an electrical measurement signal, the measurement value of which corresponds to the measured thickness of the fiber material.
This kind of measuring element is installed on spinning machines to determine the thickness of the fiber material. Such an element is, for instance, customary for the regulation of the draw works for carding, drawing, or ring spinning machines as well as in the regulation of the entry of fiber material into the spinning box of a rotor spinning machine. The measurement value output by said element is sent to a regulating means which controls the operation center of a spinning machine. The development of a spinning machine with higher productivity is accompanied by an increase in the speed of the fiber material. In place of spinning machines, this advance in regard to a stretch machine will serve to explain the development.
From an original delivery speed of 850 m/min, a speed of 1000 m/min has been achieved, in the case of delivery from modern stretch works. Accordingly, the speed at the feed end is substantially increased. Since regulated stretchworks have a measuring instrument for the control of the delay, in every case, an increasing speed of the fiber material at the measuring instrument is relevant.
It is generally recognized that a disturbing error in the measurement signal is produced when the speed of fiber material is in a startup phase, or the fiber material finds itself at a standstill. This is also true in regard to speed changes at the measuring instrument as a result of the regulation of the delay. It becomes evident, that upon acceleration or braking of the movement of the fiber material, the error of the measured signal will be just that much greater, in direct proportion to the speed difference of the fiber material to be measured.
The disadvantage of this is, that in the presence of speed differences with the moving fiber material, a misleading measurement signal is produced. Upon further conditioning in the control apparatus of a spinning machine, this signal is noticeably disturbing, lending to faulty regulation.
In the case of regulated drawframe, this situation brings about faultily tensioned fiber material during startup, as well as at standstill or during speed changes at the time of can exchange. This yields clear deviations in the band number as opposed to the band number derived from the operational speed.
This quantitative embracing of the speed related error in the measurement signal first became clear upon the installation of digital technology. As a result of a more exact computational ability for the evaluated measurement values, the quantitative effect of the error became noticeable. Previously, the error was always estimated as negligible. From this background, questions arose in regard to the reason for the error.
The fiber material, as occurs with natural fibers, has a fuzziness, a roughness, or hairiness. On this account, there are air inclusions between the fibers. Upon increasing speed of the fiber material, the interfering influence of this factor becomes evident at an increasing rate, in spite of uniform pressure of the feeler means on the fiber material.
SUMMARY OF THE PRESENT INVENTION
It is therefore a principal object of the present invention to correct, in a textile machine, the speed related error in signals from a measurement instrument which touches the fiber material, i.e. fiber band, for the determination of the thickness, or the weight of the fiber material or fiber band. Additional objects and advantages of the invention will be set forth in part with the following description or may be obvious from the description, or may be learned through practice of the invention.
In the case of high speeds of the fiber materials in modern industrial spinning machines, the connection has been found, that upon increasing speed of the fiber material, the degree of the compression of the fiber material by the feeler means of the measuring instrument is lessened, although the specified applied pressure through said feeler instrument remains essentially the same. This leads to an error, dependent on the speed of the fiber material, in a signal regarding the thickness of the fiber material. This becomes obvious, when the error-carrying measurement signal is employed for such an important function, such as, for instance, the regulation of the delay of the fiber material. This erroneous reading might further be used for quality control supervision of the fiber material or a quantity based apportionment of the material feed into the spinning machine. In the older machines, this influence was not sufficiently brought into correction curves for the measurement signal. The concept "fiber material" is to be understood particularly as one or more fiber bands in a textile machine, i.e. draw frame or stretch works.
The quantitative development of the error in measurement signals in relationship to the speed of the to-be-measured fiber material up until now has not been exactly understood. It has been discovered, that the error in the measurement signal represents a function with a rising monotonic, particularly logarithmic curve.
Proceeding from that assumption, at a speed of 0 m/min (standstill), the error has a value of zero. Further, the error is observed up to about 25%. This range of error represents the possible operational situations for the fiber material, and therewith, the greatest error to be compensated for in the said measurement value.
The functional curve of the error shows, that the error is dependent on the speed of the fiber material and the kind of fiber material. Upon startup from standstill in a spinning machine, the fiber material runs through, for instance at the feed end of a stretch works, at speed values from 0 m/min to 290 m/min.
An exact replica of the functional curve of the error, for instance during startup, is scarcely possible to obtain. On the grounds of the customary switching time of digital measurement technology (represents a digital step), the existing intervening values between a measurement reading and the following measurement reading cannot be captured.
During a very short machine startup (about 100 ms) for the fiber material up to operational speed (approximately 290 m/min), an extremely short gate time must be achieved to obtain a sufficient speed measurement in the short startup time. A high resolution, expensive pulse generator would be required. This possibility acts to the contrary, in that with low rotational counts (the RPMs practically zero) such a small pulse frequency of the pulse generator would evolve. In the case of an extremely short gate time, no pulse could be captured for individual gate times.
These factual conditions show themselves in the startup phase as hindering features for the installation of the digital pulse frequency measurement for the exact reproduction of the course of the fiber intake speed and band thickness error.
It has been found that faulty measurement values from a function can be corrected through corresponding assigned values, which are derived from an inverse function. For each measurement point of the speed of the fiber material, there is produced a corresponding error of a measurement value and a corresponding corrective value from an inverse function.
For this purpose, one requires the exact functional curve of the error in relation to changes in the entry speed to determine the exact curve of the inverse function thereof.
Only with an exact, inverse function curve are exact corrective increments available for each value of the entry speed. If the functional curve of the error is not precisely determined, that is, without omissions, then the inverse function derived from the basic function cannot be exact. Within the framework of the invention, the determination of the functional curve of the error (exact) has been omitted. To a much greater extent, the goals of the invention concentrate on a direct determination of the corrective value.
The fundamental, basic, general principle on which the invention rests, lies in that, for a given value, in particular a measured value, there is a respective inverse and speed-dependent corrective value formed. By means of this corrective value, each value will be correspondingly corrected. Collectively, there arises from the measurement values, in dependency on the speed of the fiber band, an advantageously monotonic rising (or falling) course of the functional curve and from the corrective values, an inverse advantageous monotonic falling (or rising) curve. By an inversion of the measuring value curve, that is to say, the single values, an error corrective of the faulty value is obtained. By means of the direct assignment of a correction value for the faulty value, a speed dependent direct influence of the regulation of a stretch machine is attained. Upon startup in accord with correction of the faulty measuring value, a comparison of the fiber band enters, which during the startup extends through the stretchworks. The value to be corrected can, for instance, also be an average of several measurement values or the like.
Within the framework of the invention, it is foreseen to develop this general principle in an empirical and an automatic way, that is, a self teaching concept. In both cases, it will be achieved that the corrective measure curve, after difference computation from faulty measurement value and the respective corrective value, will result in a straight line, which is, essentially parallel to the abscissa. In this case, the settings curve exhibits an increase from zero upwards. After correction of the speed dependent error (measured value), by means of a corresponding, likewise speed dependent correction value, the error free measured value is essentially not speed dependent. First, the empirical correction procedure and its apparatus will be described.
To have a background for an empirical approach for the motion of the fiber band during a change in speed, signals proportional to that change in speed must be produced by means of a measuring instrument. These signals can include, for example, a pulse train or a pulse train with a predetermined pulse repetition rate. This measuring instrument can advantageously be a pulse generator, which is coupled with a roll pair, in particular a fiber material contacting pair. What is measured then, is the rotational velocity of the contacting roll pair, which is an equivalent for the speed of the fiber material running therethrough.
The proportional speed signals thereby emitted, that is the pulse train of the pulse generator, are sent to an evaluation apparatus. The evaluation apparatus includes apparatuses for determination, transducing, and adaption.
The determination apparatus ascertains the pulse repetition period of virtual segment distances on the circumference of the contact rolls relative to the intake speed of the fiber material, such as at startup, at stand still, or in delay related alteration in speeds. In this way, each value of the intake velocity may be assigned to a specific pulse length. The pulse length, in its relationship to the intake speed of the fiber material reflects a monotonic falling, particularly an exponential curve. This determined, monotonic downward curve of the function corresponds to an inverse function curve. This inverse function curve represents a monotonic but upwardly directed and logarithmic curve of the error. In order to work with values from this inverse curve, each value of the pulse length must be converted in a transducing apparatus into terms of frequency.
In a further step, there is effected through inverse formation a transposing of the pulse length. From this transposition, which expresses a kind of reversal or a negation of the measured value, there is formed a delineated outline around an increment of the monotonic falling inverse function in which the value of the pulse length exists.
Each value of the pulse length is eventually input to an adaption apparatus. In this adaption apparatus, the relationships of the fiber material in use are given consideration or matched. This "matching" can be brought about, for instance, by a reinforcement or a weakening. The resulting value, which is now conditioned, represents a corrected value that is now to be used in a corrective apparatus for the correction of the faulty original measurement value.
In order to ascertain, that the now "valid" correction value has its source in the proper inverse function, a "plausibility-examination is executed. To two given speed values, selected as far from each other as possible, the correction, determined as above, is given consideration. In both cases of the speed value, the amount of difference must lie on a common "median line". The "median line" runs parallel to the abscissa. The said examination will show, only by means of the "median line", that the corresponding inverse function has been found.
The correction procedure has the advantage of being independent of the characteristic line of the fiber material at machine startup. The correction procedure accordingly, also operates independently of the speed. Since the same lengths of fiber material sections are being observed, the procedure in this concept is "length dependent".
Besides the above explained empirical correction procedure, it is possible in an alternative development of the general principle to construct the correction procedure as self-teaching. In this way, the error function, contrary to the empirical way, is determined automatically and self sufficiently, so that each faulty and speed-dependent measurement value is corrected immediately by means of self-optimizing and automatic operations without outside intervention. The compensation of the error of a measurement value is done continuously during the operation of the stretch machine. Besides this, the formation of a dynamic adjustment of the error function is provided. By means of the self-correction procedure, it is not necessary to consider material and machine conditioned characteristics and/or the effect of further possible influences.
In accord with the invention, a correction value is evolved out of the measured values of the measuring instrument and a comparative measure value is made. By means of this so developed correction value in combination with the original measured value of the fiber band, the measured values are corrected. All employed and developed values are, on the input side, directly or indirectly connected with the measuring instrument.
It is particularly of advantageous if the measurement value of the fiber band, and/or the correction value, and/or the comparative value, and/or the corrected value is determined in connection with the speed of the fiber band.
In this way, the dynamic adaption and automatic correction of the procedure is achieved in such a manner that the procedure essentially attains a result, which is independent of, but applicable to, all speeds of the fiber band. By the speed-relationship of the thus determined values, these values are dynamically and continuously adjusted. This automatic adaption leads to an autonomous functional operation, without intervention into the run of the process from outside.
Further, it is of advantageous worth if the measured values of the fiber band are captured in predetermined band sections. The procedure takes cognizance of the fact that the fiber band cannot be continually subjected to measurement technology, but rather it is to be measured in sections of predetermined length. The length of the fiber band under examination is chosen adequately small, for instance 30 mm, so that upon startup of the stretch works, the various speeds of the to-be-stretched fiber band are captured upon entry into the textile machine.
Moreover, the fact that average values can be formed from the measurements of the fiber band is advantageous. This average value is presented, in a further development of the procedure, as an average value of a measurement captured by the measuring instrument from the section of the fiber band. In this way, each fiber band section can be assigned an exact average value.
In particular, the dynamic and self teaching auto-correction is advantageously designed so that if the comparative measurement value is expressed as a speed-dependent value at high speeds of the fiber band.
In the case of high fiber band speeds, it may be generally assumed, that the measured values differ insignificantly from one another. That is, the relative change of the measured value is very small. The comparative value so determined serves as a reference for the formation of the correction value.
Further, it is to be preferred that the average value of the fiber band also plays a part in the value of the comparative measurement, particularly if the latter is a sliding scale average. The comparative measurement value forms, respectively, a definite speed of the fiber band section. By means of averaging of the respective average values for several startups, then the determined average measured value of a fiber band section at a definite speed is once again established, so that spontaneous swings in value are averaged out. As a result, one obtains a function which is essentially stable, practically free of value swings, and is dependent upon the speed of the fiber band. In addition to this, the comparative measured value that is used as a reference has a base with small or negligent value swings. In order to acquire the most actual data for the automatic correction, the average values are collected together in accord with the FIFO-principle in a sliding scale average value, for instance, over the most recent 16 startups.
In order to have visible evidence in regard to the textile machine and the fiber bands, the sliding scale average value is advantageously converted into a "Correction Graph" or a "Correction Table." By means of the recording of these values, the data can be analyzed during or after the operation period. Quality and excellence of the produced fiber band and of the operation of the textile machine can be monitored. In a favorable manner, the deviation, that is the correction value, of the fiber band is arrived at from the difference of the average value at high speeds of the fiber band and the average value of a fiber section. By the assignment of the fiber band average value to a respective correction value during the same speed, the individual deviation from the reference value is achieved.
Moreover, the correction measured value is advantageously calculated out of the measured value of the fiber band and the correction value.
That means each measurement value of the fiber band, i.e., the fiber band section, is individually corrected by the deviation of the average value over the entire fiber band section by reference values (average value of several startups of the fiber band at a high speed of the fiber band). In this matter, one proceeds from the assumption that the speed of the fiber band within the length of the selected section is small or scarcely changed. On this account, the selected fiber band section must be very short.
In a development of the invention, collected values, which were taken by the measurement instrument or produced by the method of the invention, were assigned memory storage addresses in at least one memory device, i.e., one computer. By means of conversion of the values into digital values and with the memory device or computer, the obtained data can be easily and quickly managed and computed. With the high capacity and favorable computer chips, now devices are available, which can manage large quantities of data. By the installation of multi-processors, the self teaching auto-correction process is easy and economical to realize.
It is advantageous if the storage addresses of the memory device, i.e. computer, are addresses in dependency on the speed of the fiber band. This makes possible a substantially better and more favorable management of the data. Especially advantageous, in accord with the invention, is the obtaining of virtual band segments of constant length. The pulse length of these segments is determined by means of an apparatus for pulse length measurement. In accord with this, the speed of the virtual band segment is determined. At low fiber band speeds, a large period length arises which, with increasing band speed, becomes lessened. Since the changes of the measurement error at startup are very large, more memory storage is required than at higher speeds of the fiber band, because the relative change of the measurement value at higher speeds in comparison to lower speeds is small. By means of converting period lengths into frequencies, large period lengths, i.e., low frequencies, match up with a large memory demand, and conversely, small period lengths, i.e., high frequencies, match up with a small memory demand.
Through this addressability of the storage spaces with dependency on the speed of the period length, the storage needs can be optimally managed, since little redundance in the data record is present. In the case of startup, more memory capacity is required than during high speed operation of the fiber band. The respective storage address is then, in an advantageous way, defined as a function of the period length, i.e., frequency, of a virtual band segment of constant length. Because of the addressability of the storage (RAM) one obtains an exact copy of the graph of the function.
In order to make a long term record of the machine, the correction graph or the correction table can be advantageously generated or executed during a can exchange of a textile machine. With the correction graph as a reference, the determined measurement value, i.e., sliding scale, may be inferred. The usefulness of a correction table serves for the partitioning and equalization of the computer capacity, if a processor is being used, which possesses too small a computer capacity.
Moreover, it is a goal of the invention to propose an apparatus with which the automatic correction procedure can be carried out. The apparatus for error correction exhibits a measurement instrument, which captures the measurement value of a fiber band running therethrough and inputs the measurement to a correction apparatus. The correction apparatus sends the adapted value to a regulation system for an operating control of a textile machine, in particular, a stretch works. In accord with the invention, the apparatus is developed in such a manner that the correction apparatus contains a device for the formation of the corrected measurement value, it also contains a correction value apparatus, wherein the device for the formation of the corrected measurement value is connected on its input side with the measurement instrument. The measurement instrument captures the original measurement and on that same input side with the correction value apparatus. By this means, measurement values of the measurement instrument are sent parallel to one another to both apparati, (first, apparatus for formation of the corrected measurement value, and second, correction value apparatus).
The correction value apparatus is connected on the output side of the apparatus for the formation of the corrected measurement value. In the correction value apparatus, the deviation of a measurement value from a reference value is determined and forwarded to the apparatus for the formation of the corrected measurement value. In this apparatus, each measured value captured by the measurement instrument is given the corresponding corrective value at the same speed of the fiber band. As a result, the corrected measurement value is sent to a further unit, i.e., the regulation system.
In a further development, the correction value apparatus includes an apparatus for the formation of correction values, which is connected on the input side of an apparatus for the averaging of the measurement values and, further, connected to a comparative measurement apparatus. For the simplification of the automatic correction, average values are developed by a predetermined small fiber band section in the apparatus. The comparative value apparatus delivers a reference value.
Moreover, it is advantageous if the comparative value apparatus is connected on the input side of the apparatus for the average value formation. By means of this connection, the execution of the automatic correction of the determined average value of the fiber band is used for the determination of a reference value. The reference value determines itself therein, in that the relative error change of the measured value at high speeds is very small.
Advantageously, the comparative value apparatus includes an apparatus for the formation of sliding scale average values and/or an apparatus for formation of a correction graph or correction table. By this means, the reference value can be very easily determined.
The correction apparatus is designed into an advantageous embodiment of the invention by means of at least one computer unit. By the availability of computer capacities, the large data quantities can be well managed and evaluated. The computer capacities allows the corrected measured values to be forwarded to the regulator unit or another operational element, in order that the measured position of the fiber band can be correspondingly regulated.
Further, it is provided that the correcting apparatus possesses storage means for the data.
Also, in accord with the invention, the correction apparatus is connected with a feeler apparatus (i.e., a feeler roller), for the fiber band, i.e., the fiber band sections, and/or connected with their device for determining their speed. In accord with the invention, virtual band segments with a constant length are measured, whereby the period length of a band segment will be correspondingly determined. By means of the connection of the correction apparatus with the feeler apparatus, the values can be assigned to one another in the respective sections depending on the speed of the respective section.
Moreover, it is advantageous, if the memory storage apparatus is addressable depending on the speed of the fiber band, i.e., the fiber section. Because of this definite relationship between speed and the values stored in the computer equipment, a definite assignment does exist.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, the invention will be explained in more detail with the embodiments shown in the drawings.
FIG. 1 shows a schematic presentation of the apparatus for the execution of the empirical correction procedure;
FIG. 2 shows schematically, the adjustment setting curve of the empirical correction procedure;
FIG. 3 shows a schematic presentation of an apparatus for a self-optimizing correction procedure;
FIG. 4 shows a schematic presentation of an alternative to the self-optimizing correction procedure; and
FIG. 5 shows a schematic presentation of the graphs of the function.
DETAILED DESCRIPTION
Reference will now be made in detail to the presently preferred embodiment of the invention, one or more examples of which are shown in the figures. Each example is provided to explain the invention, and not as a limitation of the invention. In fact, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a further embodiment. It is intended that the present invention cover such modifications and variations.
FIG. 1 shows fiber material FM in transport in the direction of the arrow. In front of an operational element AO, the fiber material FM is tested for thickness by a feeler or contact roll pair TR 1 and TR 2 . The operational element AO is comprised of stretch works or drawings elements VS. The stretch works VS possess an output delivery roll pair W 5 , W 6 , which assures an approximately constant delivery speed for the fiber material FM. The change of the delay is carried out by a regulating motor RM. The regulating motor RM is equipped with a planetary gear drive PG. Through this planetary drive PG, the regulating motor RM imparts to the stretch roll pairs W 1 , W 2 and W 3 , W 4 in case of a change in stretching, i.e., an increase or decrease in speed of rotation. These stretch conditioned rotational speed changes carry over to the contact roll pair TR 1 and TR 2 because of their mechanical coupling to the stretch roller pairs W 1 , W 2 and W 3 , W 4 .
The feeler roll pair TR 1 , TR 2 possesses a stationary, rotating feeler roll TR 2 and a pivotably movable feeler roll TR 1 . The movable feeler roll TR 1 is pressed against the stationary, rotating feeler roll TR 2 with a constant pressure. Upon change in the thickness of the fiber material, the movable feeler roll TR 1 changes its thrust. This change in thrust is converted to an electrical signal by a signal transducer SW. This electrical measurement signal represents the thickness of the fiber material. This signal then is sent to an analog/digital transducer 12. The output forms a digital measurement value of the measurement signal. This measurement signal or valve is input into a correction apparatus 1. In correction apparatus 1, a corrective value is produced, which corrects the measured value for the amount of the error. The so corrected measurement is sent to an adjustment regulator 2, which can bring about, based on the correction, a change in the rotational speed of the regulating motor RM. Upon the accomplished rotational speed change of the regulating motor RM, a stretching tension change in the stretch works is effected.
In the following, the explanation will emphasize how the correction value is generated.
A necessary element is a measuring instrument which produces a signal proportional to the speed of the movement of the fiber material. This can be, for instance, an instrument operating on either an analog or digital basis.
In accord with FIG. 1, a digitally operating pulse generator IG is coupled mechanically with the feeler roll TR 2 . The transport speed of the fiber material FM is proportional in relation to the rotational speed of the feeler rolls TR 1 , TR 2 . As a result of the mechanical coupling between the feeler roll TR 2 and the pulse generator IG, the latter outputs a pulse repetition frequency proportional to the speed. This speed-proportional pulse repetition rate is input into an apparatus 3 for correction rate generation. The apparatus 3 includes within itself, an apparatus 4 for period length measurement, a transducer 5 and an adaption apparatus 6. The apparatus 4 for period length measurement also contains an apparatus 7 for providing virtual path segments, i.e., the generation of pulse periods. The apparatus 7 for providing virtual path segments, as stated, contains the speed proportional pulse repetition rate. By means of interrupt control, for instance every 20 pulses is periodically marked off, that is, produced. The distance from one up to the 20th pulse corresponds to a period. This period is so chosen, because it reflects a travel section of the fiber material transported between the contact feeler roll pair. In the way of example, the distance between every 20th pulse from the pulse repetition rate represents a length of transport of 30 mm. The circumference of the feeler roll is apportioned into circular segments of known length, for instance 30 mm). Such periods are input to the period length counter 9. An oscillator 8 delivers pulses of a specified frequency. After the running of a period, then the period length counter 9 delivers the result to a period length intermediate memory 10. The period counter 9 is switched to "reset" and operates in renewed condition with the subsequent period.
A compilation of these values or the period length provides a monotonic, decreasing, particularly logarithmic curve to which an inverse function for the error curve may be plotted.
So that this inverse function, because of its endpoint at infinity, can be useable, intermediate steps allow its use for the error curve. For this purpose a conversion computation of the values of the period length T to values of frequency is made, and then a retro-calculation of the values to period length is computed. These calculations are realized by transducer 5.
The value from transducer 5 is input to the adaptor 6. In adapter 6, the value adaption to the fiber material being used occurs. In adapter 6, the characteristics of the fiber material are taken into account, such as fuzziness and compressibility. This is done by means of a multiplication factor, that correspondingly reinforces or weakens the respective value. Thus, the fiber band-dependent influences, i.e. factors, can be determined by an empirical method of operation and input into adapter 6 as pre-specified data. In this way, the inverse function is so brought into a coordinate system, that it lies precisely on the speed dependent error curve. In a further development of the invention, adapter 6 can be manually activated, that is, in accord with the type of the fiber, the adaption can be altered by the operating personnel.
This so adjusted correction value now leaves the adapter 6 and exits apparatus 3, whereupon it is sent into correction apparatus 1. The correction of each original measurement value by this incoming corrected value is accomplished in correction apparatus 1. Thus, regulator control 2 contains the now fully corrected measurement value.
In order to check the correction value produced by the correction procedure, that is, the position of the pertinent inverse function, a settings control is necessary.
A possibility for making this check is found in observing the resulting correction of two speed values, which lie as far from one another as possible. For each speed value, the difference between erroneous value and corrected value must lie on a common settings curve. FIG. 2 shows such a settings curve EK. Furthermore, the monotonic, rising, especially logarithmic running curve of Function K 1 is shown. For a speed value v o during the startup, a correction of x 1 has been determined.
From this is determined the corresponding erroneous value x 2 . From the erroneous value x 2 , the deduction of the corrective value x 1 gives a difference value of x 3 . An analogous procedure method will be made to another speed value v 1 . The correction value x' 1 is determined and the error value x' 2 is determined. The two determined difference values x 3 and x' 3 must lie on a straight line, which runs parallel to the abscissa. If this is the case, then the conditions are fulfilled, in that difference value x 3 =difference value x' 3 and thus to the error curve, a correctly determined inverse curve K 2 is established. That is the goal of the settings curve.
In actual practice, it may come about, that the settings control does not immediately show an equivalence of the difference values of x 3 and x' 3 . In such a case, for instance, it is required that through an optimizing procedure (iterative procedure) the equality of the different values x 3 and x' 3 are fixed. The finding of this optimal value can be done as follows:
The correction procedure is isolated from the stretch operation. Therefore, the machine obtains no correction values, that is, no faulty measuring values would be delivered. The possibility exists of examining the pressure of the contact roller at various values of the speed, including during the startup. The pressure is changed in one direction and again installed with a new value. Then the measurement is taken again at a different speed and the determined increase between the two points is examined in regard to its approach to the real, predetermined error curve.
FIGS. 3 and 4 show, respectively, an embodiment of a correction apparatus 20, 30, in accord with the self teaching and self optimizing error correction at band measuring sensors, i.e., on a stretch works or drawing equipment. In both cases, the correction apparatus 20, 30 respectively are loaded on the input side with measuring values TW of a known measuring instrument (see FIG. 1). Each of the correction apparatuses 20, 30 are further comprised of a correction value evaluation apparatus 21, 31 and an apparatus 22, 32 for the formation of the correction measurement value. The two apparatuses 21, 22, 31, 32 are supplied in parallel paths with the measured value TW. From the output side, the corrected value apparatus 24, 34 delivers a corrected value to the apparatus for the formation of a corrected measurement 22, 32.
The correction apparatus 20, 30, on its outlet side, sends the error-free measuring value which is produced for formation of corrected measuring values in the apparatus 22, 32, to a regulator 2 for operational control.
The measuring value TW delivered to the correction value apparatus 21, 31 from the feeler roller, which presents the measurement value of a fiber band segment, were averaged in an apparatus for average formation, 23, 33. From this apparatus for average formation, the averaged mean value MW of a fiber band segment is forwarded to a comparator apparatus 25, 35. In this comparator apparatus 25, 35, the average values, which were made at a particular fiber band speed, were compiled on a sliding average from about 16 starting operations of the machine. This apparatus operates in accord with the FIFO principle, that is, if, over n runs of band, a sliding average is formed and after a further start, the (n+1) average value is obtained at this specific speed, then the first average value is struck out and the new (n+1) comes into consideration for the new sliding average value GM. This process assists in that only actual values for the determination of a comparative value are brought into the computation. The comparative measured value is a value from the obtained function graph which is obtained as an average value determined at high fiber band speeds. At this high speed, the relative change of the measurement is negligibly small, so that a nearly error free measurement value can be assumed. The sliding average GM used as a reference value, found at a high fiber band speed, is sent to an apparatus for the formation of corrective values 24 (FIG. 3).
The average values of a fiber band segment MW will, simultaneously with the above, be sent in parallel directly to the apparatus for the formation of correction values 24, 34. In this apparatus 24, 34, the difference between the reference value and the average value MW of a fiber band segment is formed. As a result, the error deviation is obtained, that is, the error FW. Error FW is forwarded from the correction value apparatus 21, 31 to the apparatus for the formation of the corrected measurement values 22, 32. At this apparatus 22, 32, the measurement data from the feeler roll TW is delivered parallel to the illustrated conditioning path in the correction value apparatus 21, 31.
In the apparatus 22, 32 for the formation of the corrected measuring value, the sum of the measurement data TW and the error values FW is made. As a result, essentially faultless measurements are obtained that, for instance, can be sent further to a regulating unit.
In the development and alternatives of the procedure and the apparatus of FIG. 3, it is possible as in FIG. 4, to forward sliding average value GM which was formed in the comparator apparatus 35, to an apparatus 36 for the formation of a corrective graph or a corrective table. From this correction table, in the above described concept the comparative value will be determined, which is forwarded to the apparatus for the formation of corrective value 34 (FIG. 4). The transfer of the sliding average value GM in a correction table KT is to only be preferred when insufficient computer capacity is available and thus, supplies a compensation for the over-demand on the processor. The transmission of the sliding average value GM into the correction table KT can be done advantageously, when a can exchange is being made on the machine.
By means of the constant updating (above all, the sliding average GM), new data always stand available for the correction of the measured values, which represent the actual characteristics of the fiber band that are at hand in the textile machine. In this way, the procedure is self teaching and self optimizing and takes on the characteristics of the fiber bands currently running in the textile machine. It also takes on the characteristics of the production relevant influences, so that a dynamic adaption of the measured values is updated and carried out continuously.
For an easier management of the data, the presented procedure is designed into a computer apparatus with storage addresses. Since, in accord with the procedure, measurement of virtual fiber band segments with a constant length were taken, the period lengths of which were determined by an apparatus for period length measurement (see FIG. 1), then the measured period length may be used for the purpose of addressing the RAM storage cells of the computer equipment. Since each storage cell is assigned a specified speed of the fiber band, then an exact reproduction of the function graph of the measurement values and the deviation is stored therein.
Contributing to this is the apparatus for the period length determination connected with the correction apparatus 20, 30. In a further alternative, the apparatus for period length measurement is connected with individual apparatuses for the correction apparatus 20, 30.
In FIG. 5 the function graphs of the average values M is presented, that is, the sliding average and the deviation F in connection with the fiber band speed. The function graph M represents a monotonic, rising function curve which approaches a straight limit line asymptotically. In accord with the procedure, in the case of a high speed of the fiber band v H , a reference value M H is determined. From this reference value M H , all other values of the function graph M are drawn. On this basis, the deviation of the respective measurement values is formed which provides the deviation curve F. Thus, at every speed to each determined measurement value, a corresponding error value, i.e., deviation value, is uniquely determined. For instance, at a low fiber band speed v L , an average M L with the deviation value F L is determined. For the correction of the measurement value M L , the sum is formed out of the two values of M L and the deviation value F L .
In this way, the error-free measurement value M' L is obtained which is forwarded to the regulation control unit of a stretch works.
The advantage of the self teaching, self optimizing procedure is, that the error function, that is to say, the deviation of the respective measurement values are found on an individual basis, which adapts itself to a compensation of the measurement error. It is not necessary that any manual corrective operation from the outside must intrude into the operating sequence of the correction procedure.
Altogether, the invention makes possible a better control of the fiber bands, for instance, in a stretch machine and upon startup of a stretch machine. This can be carried out just as well either on an empirical basis or in a self-optimizing manner. | The invention concerns a procedure for correction of error of speed and mechanical related error, particularly in the thickness of a fiber band in a textile machine, especially stretch machines. The purpose of the invention lies in the correction of the speed related errors in measurement signals from an instrument of the textile machine. This purpose is achieved by each measurement value generating a respective corresponding inverse and speed related correction value. By means of this correction value, each measurement value can be correspondingly and individually corrected. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to window blind assemblies and, more particularly, to a blind assembly particularly well adapted for mounting over doorlights.
Window units incorporating blinds are well known in the prior art. These units include two panes of glass an a blind assembly sandwiched between the two panes. The blind assemblies include mechanisms both for raising and lowering the blinds and for tilting the blind slats. The units include slides or knobs or handles coupled to the mechanisms and accessible from the outside of the unit. When a window unit is especially designed or adapted for installation in a door, the unit is referred to as a doorlight.
Because it is difficult, time-consuming and costly to replace existing doorlights with doorlights having integral blinds, retrofit assemblies have been developed for retrofitting blinds over doorlights. These retrofit assemblies include a frame that supports both a pane of glass and a blind assembly. The frame is attached over the frame of the existing doorlight such that the blind assembly is sandwiched between the pane of the assembly and the existing doorlight. Screws are typically used to attach the assembly to the doorlight and/or the door. One particularly good example of a retrofit assembly is illustrated in U.S. Pat. No. 5,996,668 issued Aug. 14, 1998 to DeBlock et al.
Retrofit units are superior to the simple attachment of a blind assembly first because the retrofit units protect the blinds from wear and tear and encase the cords of the blind assembly. Freely hanging cords can be a hazard to children and pets. Second, the retrofit unit confines the blind and prevents the blind from swinging into the door as the door is opened and closed or during high winds, thus preventing damage to the blind and the door. Finally, the encased window blind is more aesthetically pleasing than a traditionally hung window blind; and the encased blind requires cleaning less frequently, if ever.
Despite the advantages of these systems, there is room for improvement. First, the cords in the units can become tangled if the blind is permitted to free fall within the unit and/or if the unit is inverted (e.g. prior to or during installation). Second, the mechanism of the units often are visible along the sides or edges, contributing to an unsightly appearance. Third, the units require a considerable amount of time to install. Fourth, the fasteners for the units leave permanent marks (e.g. holes) in the face of the door, which are unsightly if the retrofit unit is removed. Fifth, stocking of units of blinds having different colors creates a significant inventory issue. Sixth, replacing a blind in a unit is extremely difficult, if not impossible. This can be a problem if a consumer wishes to change the color of the blind assembly or if a defective blind must be replaced. A consumer usually replaces the entire unit if they wish to change the color of the blind.
SUMMARY OF THE INVENTION
The present invention overcomes the noted problems by providing a an improved retrofit doorlight blind assembly having several novel features.
In a first aspect of the invention, the operator mechanism for the raise/lower feature includes gears and a toothed drive belt to ensure positive engagement of the drive mechanism. More particularly, a first gear drives the blind operator rod; a second gear provides an idler, and the toothed belt is looped around the two gears to provide the driving mechanism.
In a second aspect of the invention, the frame includes multipurpose blind guides. First, the guides have a C-shaped section that surrounds the edges of the blind to guide the blind during raising and lowering. Second, the guides secured the glass panel within the frame. Third, the guides hide the mechanism from view. And, fourth, the guides reinforce the frame.
In a third aspect of the invention, the assembly includes an improved mounting system for mounting the retrofit assembly over a doorlight. More specifically, the mounting system includes a top bracket that is secured behind the top of the doorlight frame on which the assembly is easily hung. The system also include latches that lock behind a lower portion of the doorlight frame to secure the bottom of the assembly.
In a fourth aspect of the invention, the blind snap-fits into the assembly frame so that the blind is easily attached to and detached from the frame. Specifically, the blind assembly includes a catch that snaps into a slot on the header. This feature reduces inventory, because assemblies can be made to order by snapping any one of a plurality of blinds (e.g. having a desired feature such as color) into a common frame. This feature also facilitates subsequent changes to the assembly, such as replacing a blind having one feature with a blind have a different feature.
In a fifth aspect of the invention, the blind actuator rod includes an improved technique for securing the actuator cords. More specifically, small barrels are mounted transversely in the rod; and the actuator cords are secured within the barrels. This technique eliminates the prior art need to glue the cords to the barrel, with the attendant manufacturing difficulties and costs.
These and other objects, advantages, and features of the invention will be more readily understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of a door incorporating the blind assembly of the present invention;
FIG. 2 is a front elevational view of the blind assembly;
FIG. 3 is a rear perspective view of the assembly;
FIG. 4 is an exploded fragmentary view of the assembly;
FIG. 5 is a top cross-sectional view of the assembly showing the blinds retained in the frame taken along the line V—V in FIG. 3;
FIG. 6 is a rear elevational of the interior of the header of the blind assembly;
FIG. 7 is a side cross-sectional view of the height control mechanism taken along line VII—VII in FIG. 3;
FIG. 8 is a fragmentary side cross-sectional view of the door of FIG. 1 taken along line VIII—VIII;
FIG. 9 is a fragmentary bottom cross-sectional view of the door of FIG. 1 taken along line IX—IX; and
FIG. 9A is a front elevational view of a clip of the assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A blind assembly according to a preferred embodiment of this invention is illustrated in FIGS. 1-3 and generally designated 10 .
I. Structure
The assembly 10 includes a window pane 12 , a frame 20 , a set of blinds 22 , a tilt control mechanism 24 , and a height control mechanism 26 . The assembly 10 is described for installation over a door D and doorlight L. However, the assembly 10 may be installed over other, various window types.
The frame 20 is preferably molded of plastic, although other materials, such as wood or metal, may be used. The frame 20 includes top and bottom sides 28 and 30 and left and right sides 32 and 34 . The sides 28 , 30 , 32 , and 34 meet at right angles and form a rectangle, although the frame 20 may include a larger or smaller number of sides and form other shapes, such as a triangle or octagon. A pane opening 36 is defined in the center of the frame 20 . Although the frame will be described with reference to a rectangular pane opening 36 , and accordingly a rectangular window pane 12 , it is to be understood that the opening can be of essentially any shape, such as oval or triangular.
Each of the bottom, left and right sides 30 , 32 , and 34 of the frame 20 includes a rib 40 , extending along its length. As shown in FIG. 5, the rib 40 is a substantially rectangular protrusion that extends approximately the length of the pane opening 36 on each side of the frame 20 . The rib 40 is preferably integrally molded as part of the frame 20 , however the rib 40 may be separately formed and attached to the frame 20 by conventional means.
Connected to each rib 40 is a blind guide 42 . Blind guides 42 are preferably molded of plastic, but may be produced of other materials such as metal or plastic. As will be explained below, the blind guides 42 guide the blinds 22 during use and secure the pane 12 to the frame 20 . Further, the blind guides 42 reinforce the frame 20 and prevent viewing of the internal workings of the assembly 10 when the assembly is installed. Each blind guide 42 has a connecting portion 44 and a blind retainer 46 .
The connecting portion 44 is a substantially U-shaped section of each blind guide 42 that defines a cavity, the cavity fitting over a rib 40 of the frame 20 . As shown in FIG. 5, the dimensions of the connecting portion 44 are preferably such that there is a close fit between each connecting portion 44 and the corresponding rib 40 . When connected to the rib 40 , a first leg 48 of the connecting portion 44 is in contact with the pane 12 and a second leg 50 of the connecting portion 44 is in contact with the frame 20 . This construction secures the pane 12 to the frame 10 . The connecting portion 44 can be connected to the rib 40 by any conventional means, such as the use of glue or fasteners.
Further, each blind guide 42 includes a blind retainer 46 . The blind retainer is an essentially C-shaped section of the blind guide 42 and is connected to the connecting portion 44 . The width 52 of the blind retainer 46 is approximately equal to the width 54 of the blinds 22 . When connected, the open side of the blind retainer 46 faces the pane 12 of the assembly 10 , providing a channel for the blinds 22 to travel in as they are raised and lowered during use. As with the connecting portion 44 , the blind guide has one leg 56 that contacts the pane 12 of the assembly 10 .
The connecting portion 44 and blind retainer 46 are preferably molded as an integral piece, though the elements can be formed separately and later connected. If molded as an integral piece, the back leg 58 of the blind retainer 46 and the first leg 48 of the connecting portion 44 are preferably molded as a single leg, thus connecting the two sections. If not molded as an integral piece, the back leg 58 of the blind retainer 46 is preferably connected to the first leg 48 of the connecting portion 44 by conventional means, such as the use of glue or other adhesive.
The set of blinds 22 are conventional window blinds and, therefore, will not be described in detail. The blinds include a plurality of slats 64 , preferably manufactured of vinyl or aluminum; of course, other materials such as wood may be used. As discussed above, the blinds 22 , and specifically the ends 66 and 68 of the slats 64 of the blinds 22 , are loosely retained in the blind retainers 46 of the left and right sides 32 and 34 of the frame 20 . A header 70 , as seen in FIG. 4, from which the slats 64 are suspended, is fixedly mounted on the top side 28 of the frame 20 . The slats 64 are suspended from conventional lift adjustment and tilt adjustment, or string ladder, tilt cords 74 . The lift cords 72 have first and second ends 75 and 76 ; the first ends 75 are threaded through apertures (not shown) defined by the slats 64 and secured to the lowermost slat 77 . The second end 76 of each lift cord 72 is secured within the header 70 . Front and rear tilt cords 78 and 79 extend along the front and rear edges 80 and 82 of the slats 64 . A connector cord (not shown) extends between the front and rear tilt cords 74 and supports each slat 64 . The tops of the tilt cords 74 are secured within the header 70 .
The header 70 is a substantially L-shaped bar that is connected to the top side 28 of the frame such that a ledge is formed along the top edge of the pane 12 . The header 70 can be connected to the frame 20 by any conventional means, such as integrally molding the header 70 as part of the frame 20 or connecting the two using an adhesive. The header 70 includes an attachment leg 106 . The attachment leg 106 is a short protrusion extending at a right angle from the back leg 108 of the header 70 such that the back leg 108 of the header 70 lies flat against the pane 12 and the attachment leg is connected to the interior of the frame 20 . The header 70 further includes a base leg 110 having slots 112 for the connection of the tilt control mechanism 24 and height control mechanism 26 to the frame 20 . Each slot 112 is a substantially rectangular groove in the base leg 110 of the header 70 .
As seen in FIGS. 4 and 5, the tilt control mechanism 24 includes a tilt actuator 84 , which is slidably mounted along the left side 32 of the frame 20 . The tilt actuator 84 includes a spine 86 that protrudes from the tilt actuator 84 and fits within a groove 85 present along the left side 32 of the frame. The spine 86 is preferably a substantially rectangular protrusion and the groove 85 is preferably substantially U-shaped, the height of the spine 86 being approximately equal to the depth of the groove 85 . Additionally, the tilt actuator 84 includes a rearward extending connector 88 for connecting to the remainder of the tilt control mechanism 24 , as will be explained in more detail below. The connector 88 extends inwardly from this the groove 85 into the interior of the frame 20 . Preferably, a portion of the edge of the frame is cut away along the groove 85 to facilitate movement of the tilt actuator 84 , the tilt actuator 84 being positioned along this cut-away portion 87 .
The remainder of the tilt control mechanism 24 is located within the interior of the frame 20 and is not visible to the user. The tilt control mechanism 24 further includes a tilt belt 90 attached to the tilt actuator 84 by the connector 88 . The tilt belt 90 wraps around a tilt gear 92 that is affixed to a tilt bar 94 , preferably with screws or adhesive. The tilt belt 90 preferably includes grips 98 that interfit with teeth 100 on the gear to provide a more secure grip between the two. A tilt control gear 93 is essentially identical to the tilt gear 92 and is mounted at the bottom of the frame 20 . The tilt gear 92 and tilt control gear 93 control rotation of the tilt belt 90 during operation of the assembly 10 . The tilt belt 90 is most preferably molded from plastic, although other suitable materials such as rubber and fabric may be used. A portion of the tilt belt 90 optionally consists of a spring 102 , the spring 102 accounting for thermal expansion of the resulting belt. The tilt bar 94 extends lengthwise within the interior of the header 70 and is supported within barrel 114 which snaps into the floor of the header 70 . The front and rear tilt adjustment cords 78 and 79 are secured to the tilt bar 94 .
The tilt gear 92 and tilt control gear 93 are housed within baskets 104 . Each basket 104 includes two side walls 106 and a back wall 108 . Each side wall includes a nesting portion 110 , which is a substantially semicircular ridge along the top edge of the wall. The tilt gear 92 and tilt control gear 93 rest on the nesting portions 110 of the side walls 106 . The back wall 108 connects the basket 104 and is attached to the frame 20 . The back wall 108 can be connected to the frame 20 by any conventional means, such as screwing the back wall 108 onto the frame 20 or attaching the two with an adhesive.
The height control mechanism, or adjuster, 26 includes a height actuator 120 which is slidably mounted on the right side 34 of the frame 20 . The height actuator 120 is essentially identical to the tilt actuator 84 and includes a spine 122 which interfits with a groove 124 on the right side 34 of the frame 20 . As with the tilt control mechanism 24 , the groove 124 preferably includes a cut-away portion to facilitate movement of the height actuator 120 , and thus adjustment of the blinds 22 . The height actuator 120 further includes a connector 126 that connects the height actuator 120 to the height control mechanism 26 .
The connector 126 of the height actuator 120 is attached to a height belt 128 which is wrapped around an adjustment gear 130 and adjustment control gear 131 , which are housed in baskets 104 . The height belt 128 , adjustment gear 130 and adjustment control gear 131 are essentially identical to the tilt belt 90 , tilt gear 92 and tilt control gear 93 , and therefore will not be described in further detail. The height control mechanism 26 further includes an adjustment rod 136 , a threaded rod 138 , and a rod support 140 . The adjustment rod 136 is a substantially circular rod that is connected to the adjustment gear 130 such that when the adjustment gear 130 rotates, the adjustment rod 136 rotates. Optionally, a bar can be used to connect the adjustment gear 130 to the adjustment rod 136 . The adjustment rod 136 , or at least a substantial portion thereof, is hollow and is internally threaded. The adjustment rod includes throughholes 137 through which the second ends 76 of the lift cords 72 are threaded. The first ends of the lift cords 72 are preferably knotted to secure them to the adjustment rod 136 . A cap 139 is also connected to the second end 76 of each lift cord 72 around the knotted portion to further ensure the connection of the lift cords 72 to the adjustment rod 136 .
The threaded rod 138 is a substantially circular rod having threads along substantially its entire the length, the threads of the threaded rod 138 corresponding to the threads of the adjustment rod 136 so that that threaded rod 138 can be screwed into the adjustment rod 136 . One end of the threaded rod 138 is screwed at least partially into the adjustment rod 136 and the opposite end of the threaded rod 138 being rigidly connected to the rod support 140 , such that as the adjustment rod 136 rotates the adjustment rod 136 is screwed onto the threaded rod 138 . The rod support 140 preferably includes a circular portion 142 that houses an end of the threaded rod 138 and prevents the threaded rod 138 from rotating during operation of the assembly 10 . The rod support 140 also preferably includes a clamp 144 that is connected to the header. The clamp 144 is preferably substantially U-shaped and interfits with the base leg 110 of the header 70 to connect the rod support 140 to the header 70 , and thus the frame 20 . Alternatively, the rod support may be connected to the header 70 by other conventional means, such as the use of glue or fasteners.
Each of the adjustment rod 136 and tilt bar 94 extends through barrels 114 , thus connecting the tilt control mechanism 24 and height control mechanism 26 to the barrels 114 . Barrels 114 include catches 116 that interlock with the slots 112 . Each barrel 114 is essentially two FIG. 8 shaped sections, each section having a large circle 118 beneath a small circle 120 . A base 122 is attached to the bottom of each large circle 118 and extends between the two sections to connect them. A catch 116 is a substantially T-shaped protrusion that extends from the bottom of each base 122 . Each catch 116 is designed to “snap” fit with a slot 112 on the header 70 to connect the tilt control mechanism 24 and height control mechanism 26 to the header 70 .
As can perhaps be best seen in FIG. 8, latches 150 are connected along the top side 28 of the frame 20 . Each latch 150 includes a short frame leg 152 connected to the top side 28 of the frame 20 and a door leg 154 that is substantially longer than the frame leg 152 and extends in a direction opposite that of the frame leg 152 . An intermediate leg 156 connects the frame leg 152 and door leg 154 and is preferably perpendicular to them both. There are preferably at least two latches 150 connected along the top side 28 of the frame 20 . Latches 150 can be formed from any materials, but are preferably metal, and can be connected to frame 20 in any conventional manner.
As can be seen in FIG. 9, clips 160 are connected along either the bottom side 30 or a lower portion of both the left and right sides 32 , 34 of the frame 20 . Each clip 160 is substantially L-shaped and includes a base leg 164 and an extending leg 166 . Each clip 160 optionally includes a substantially rectangular lip 162 extending perpendicularly from the base leg 164 of the clip 160 . The clips 160 are rotatably connected to the frame 20 such that, if the lip 162 is pulled, the clip 160 rotates. The clips can be connected to the frame by any conventional means, but are preferably connected to the frame 20 with screws.
II. Operation
The assembly 10 is preferably installed over the doorlight of an existing door. However, the assembly 10 may be used in conjunction with any window style or with windows in any type of structure, such as a home or office building.
Before installing the assembly, the blinds 22 must be installed. To install the blinds 22 , the catches 116 of the barrels 114 connected to the tilt control mechanism 24 and the height control mechanism 26 , which in turn are connected to the blinds 22 , are snapped into slots 112 on the header 70 . To change the color of the blinds, the barrels 114 can be detached from the header 70 and new barrels 114 , with new blinds 22 , can be snapped in.
After installing the blinds, the assembly 10 is positioned so that the blinds 22 are sandwiched between the pane 12 and the existing doorlight. To install the assembly 10 on a doorlight, the latches 150 of the assembly 10 are first placed over the existing frame of a doorlight in such a manner as to allow the door leg 154 of each latch 150 to “snap” in between the frame of the existing doorlight and the door. The snapping interaction of the latches 150 and the existing frame provides a secure connection of the assembly to the door.
After connecting the assembly 10 to the door, the clips 160 are rotated such that the extending leg 166 of each clip 160 “snaps” between the frame of the existing doorlight and the door. In this case, the securing of the clips 160 between the doorlight frame and door prevents the assembly 10 from swinging or swaying as the door is opened or closed or during windy conditions.
To raise or lower the blinds 22 , the user grasps the height actuator 120 of the height control mechanism 26 and slides height actuator 120 vertically along the cut away portion 132 of the groove 124 . As the user slides the height actuator 120 down, the height belt 128 is moved downward, thus rotating the adjustment gear 130 and, in turn, the adjustment rod 136 . As the adjustment rod 136 rotates, it is threaded onto the threaded rod 138 and the lift cords 72 are coiled onto the adjustment rod 136 , thus pulling the slats 64 vertically upward. The slats 64 may be raised to any height desired by the user. When the slats 64 are raised to the desired position, the user ceases sliding the height actuator 120 down the track 40 .
To lower the blinds 22 , the user slides the height actuator 120 vertically upward along the groove 124 . As the height belt 128 is pulled upward, the adjustment gear 130 is rotated in the opposite direction, causing the lift cords 72 to unwind from the adjustment rod 136 and lower the slats 54 .
To open the blinds 22 , the user grasps the tilt actuator 84 and slides it along the groove 85 along the left side 32 of the frame 20 to the middle of the left side 32 . As the tilt actuator 84 is moved, the tilt belt 90 is moved causing the tilt gear 92 to rotate. As the tilt gear 92 rotates, the tilt cords 74 are twisted causing the slats 64 to rotate. When the tilt actuator 84 is positioned in the middle of the assembly 10 , the front and rear tilt cords 74 are level, and the connector cords are horizontal. Thus, the slats 64 lie in a horizontal position, and the blinds 22 are opened. To close the blinds 22 , the user slides the tilt actuator 84 to upwards or downwards from the middle position. This causes the tilt gear 92 to rotate, thus rotating the tilt bar 94 and causing the tilt cords 74 to twist. As the tilt cords 74 twist, one edge of the slats 64 is pulled upward causing the blinds to close.
The above description is that of a preferred embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular. | A retrofit blind assembly for a doorlight. The assembly includes a frame, a transparent panel, and a blind snap-fitted to the frame. The blind actuator includes gears and a toothed belt for positive, non-slip actuation. A pair of blind guides are mounted on the opposite sides of the frame to receive and guide the opposite ends of the blind. The mounting system includes a pair of brackets that can be secured between the doorlight and the door and upon which the assembly can be hung. The mounting system also includes a pair of movable catches on the lower portion of the frame snap that can be locked behind the doorlight to secure the lower end of the assembly. | 4 |
[0001] This is a continuation-in-part patent application claiming priority to U.S. patent application Ser. No. 10/915,553, filed on Aug. 10, 2004, which claims priority to U.S. Provisional Patent Application Ser. No. 60/494,259 filed Aug. 11, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to the immune system, and more particularly to a unique GnRH II analog designed to be useful in the immune system and with certain immune system disorders, and its use within the immune system as a protagonist or antagonist. Such disorders can include allergies, asthma, graft versus host disease, immune deficiency diseases, and autoimmune diseases, inflammatory responses, as well as immune processes regulating implantation and pregnancy and tumor rejection.
[0004] 2. Description of the Related Art
[0005] Applicant has found that GnRH II analogs are useful in the immune system and in various immune system disorders. Applicant performed a number of studies on GnRH II in the immune system, relating to its localization and that of its specific receptor and its effect on B cells, monocytes, macrophages, dendritic cell and natural killer cells and immune system cells and functions.
[0006] It has been reported that GnRH II stimulates T cell adhesion and homing, but these effects were only seen after twenty-four hours. Thus, this effect appears to be secondary to a more immediate action. Based on Applicant's studies of GnRH II and its specific receptor localization and its activity on leukocytes, GnRH II and Applicant's GnRH II analogs directly affect monocytes, macrophages, B cells, dendritic cells, mast and natural killer cells directly. Other than Applicant's studies, no other studies on specifically designed stable GnRH II receptor analogs have been reported.
[0007] Applicant's studies of GnRH II, Applicant's GnRH II analog and its specific receptor have led to Applicant's proposal that GnRH II regulates cells of the immune system, including but not limited to monocyte and macrophage, B cell, dendritic cells, mast and natural killer cells differentiation and function. These GnRH II receptor-mediated events participate in the regulation of what is recognized to the human body to be foreign, whether it is sperm, embryo implantation, and endometrial implant, tumor acceptance, another self protein, tissue transplantation, tumor rejection or an infection such as a virus, such as HIV. These GnRH II receptor-mediated events form the basis of Applicant's invention described herein. Applicant envisions that the GnRH II and Applicant's analogs, and its interactions with the specific GnRH II receptor, when appropriately formulated and administered, can be used to stimulate or inhibit immune function. Applicant further envisions that Applicant's analog, and the use of antibodies to GnRH II, GnRH II receptors and Applicant's analog can be used for diagnosis of immune disorders, monitoring the treatment of immune disorders, and treating immune disorder.
BRIEF SUMMARY OF THE INVENTION
[0008] The present invention relates to analogs of GnRH II specifically designed to be administered into the immune system and used in immune system disorders, such as allergies, asthma, graft versus host disease, immune deficiency diseases, autoimmune diseases, inflammation and tumor rejection, immune processes regulating implantation and pregnancy, endometriosis, uterine fibroids, and immune-involved diseases. Applicant's analogs are designed to be stable in blood or tissue and resistant to degradation by peptidase or other enzymes. Applicant's analogs are designed, and as discussed herein are intended to be administered directly into the immune system for binding to immune system GnRH receptors. Applicant's analogs are not designed to be mediated through the hypothalamus-pituitary-gonadal-thymus axis.
[0009] As used herein, unless otherwise specified, reference to “GnRH I” means native, naturally occurring GnRH I having the sequence set forth in SEQ ID NO: 1 in the Sequence Listing attached hereto. As used herein, unless otherwise specified, reference to “GnRH II” means native, naturally occurring GnRH II having the sequence set forth in SEQ ID NO: 2 in the Sequence Listing attached hereto. As used herein, unless otherwise specified, reference to “GnRH II analogs,” “Applicant's analogs”, “the analogs of the present invention” or the “analogs” means Applicant's GnRH II analogs having the sequence set forth in SEQ ID NO: 3 in the Sequence Listing attached hereto.
[0010] Applicant specifically incorporates the material contained in the attached Sequence Listing herein by reference. The Sequence Listing is attached in an ASCII text file, identified by the name “Sequence Listing.txt”, which was created on Aug. 27, 2010. The Sequence Listing file has a size of 1.08 KB.
[0011] Applicant's GnRH II analogs of the present invention may act either as an agonist of GnRH II with acute direct action on the immune system or as an antagonist using chronic delivery at immune system receptors leading to down regulation. Applicant's analogs may also act as a pure antagonist of immune system GnRH II at the GnRH II receptor.
[0012] The analogs of the present invention are resistant to enzymatic degradation by enzymatic activity of peptidases or other enzymes. The GnRH II analogs' resistance to degradation by peptidases or other enzymes is due to the substitution of a D-amino acid at position 6, and the substitution at the C-terminus (position 10 of Applicant's analogs) with an amino acid-amide.
[0013] Specifically, Applicant's analogs are GnRH II analogs that are modified at the C-terminus by an amino acid-amide substitution. Any suitable amino acid-amide substitution at the C-terminus, including but not limited to aza-Gly 10 -NH 2 substitution, may be used making the sequence more stable in the circulation and in the immune system and lymph. The substitution at the C-terminus resists degradation by post-proline peptidases present in the blood, lymph and tissues. Applicant's studies have shown that substitution at the C-terminus with an amino acid-amide makes Applicant's analogs more stable in the blood and lymph and higher in binding affinity than substitution at the C terminus with an ethylamide.
[0014] Since human pituitary, blood and lymph also contain an enzymatic activity by endopeptidases that can degrade GnRH II at the 5-6 position, the present GnRH II analogs have also been designed to inhibit the endopeptidase degradation by having substitutions in the 5-6 position of the molecule. Specifically, the GnRH II analog of the present invention is also substituted at the 6-position with a D-Arg or other D-amino acid. Any D-amino acid is suitable to substitute at position 6 to reduce endopeptidase degradation.
[0015] The substitutions of Applicant's analogs at position 6 with a D-amino acid and the C-terminus (i.e. position 10 of Applicant's analogs) with an amino acid-amide are the only two positions of Applicant's analogs where substitutions are made. Importantly, the native GnRH II backbone (i.e. the native GnRH II amino acids at positions 5, 7 and 8 of the GnRH II decapeptide) must be preserved in Applicant's analogs. The native GnRH II backbone and the substitutions at positions 6 and 10 enhance the binding of the GnRH II analogs to GnRH II receptors in the immune system. The native GnRH II backbone of the analogs binds with high affinity to GnRH II receptors in the blood, lymph, thymus, spleen, and other tissues where immune cells and immune tissues are found, while the substitutions at positions 6 and 10 resist degradation, resulting in a high potency of Applicant's analogs and hence high affinity binding to GnRH II receptors. Substitution at position 10 with an amino acid-amide also increases the potency of Applicant's analogs over substitution with an ethylamide.
[0016] In fact, the stability of the present GnRH II analogs in the presence of peptidases and immune system tissues has been examined. Replacement of the native Gly 10 -NH 2 with aza-Gly-NH 2 made each of the GnRH II analogs more resistant to degradation by post proline peptidases. It was found that the less active an analog is as a competitor for GnRH degradation by peptidase, the more stable that analog will be in the immune system tissues and in lymph. Thus, the existing GnRH I analogs commonly used in medicine can be degraded much more rapidly in the immune system and lymph than Applicant's GnRH II analogs.
[0017] Because of the stability and high-affinity binding of Applicant's GnRH II analogs, there are several applications of the analogs to the immune system. Applicant's GnRH II analogs may be used to stimulate or inhibit over-activity of the immune system to treat such immune disorders as allergies, asthma, graft versus host disease, immune deficiency diseases, autoimmune diseases, inflammation, tumor rejections and immune processes regulating implantation and pregnancy.
[0018] Applicant's analogs can also be used to alter either or both the innate or adaptive immune system, such as bone, lymph nodes, circulating leukocytes, thymus lymphocytes, mast cells, natural killer cells, spleen, T-cell, B-cell, and antibody production. Applicant's GnRH II analogs may be administered in pharmaceutical preparations to treat immune system disorders.
[0019] In other embodiments, the invention provides GnRH II analogs with enhanced activity within the tissues of the immune system and lymphatic system as well as the bone, thymus and spleen. This can include, but is not limited to, enhanced activity with T cells, monocytes, macrophages, dendritic, mast and natural killer cells.
[0020] In addition, a method of monitoring a course of treatment or detection and localization of immune activity using an antibody to Applicant's analogs, an antibody to GnRH II or an antibody to GnRH II receptors to bind free GnRH II, GnRH II analog and/or GnRH receptors in the blood, lymph and immune tissues and cells is provided.
[0021] In other embodiments, the invention provides a method of diagnosing immune disorders using an antibody to Applicant's analogs, an antibody to GnRH II or an antibody to GnRH II receptors to bind free GnRH II, GnRH II analog and/or GnRH receptors in the blood, lymph and immune tissues and cells.
[0022] It is envisioned that Applicant's GnRH II analogs will be administered intravenously, intra-nasally, orally, transdermally, subcutaneously, vaginally or intramuscularly. However, virtually any mode of administration may be used in the practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 shows localization of GnRH II in the human spleen.
[0024] FIG. 2 is a graph showing stability of Applicant's GnRH II analog in serum and plasma. GnRH II Analog is stable throughout twenty-four hour of incubation in plasma and for the seventeen hours in serum following the initial serum formation.
[0025] FIG. 3 is a graph comparing antibody response for Applicant's GnRH II analog and a normal response titre. The IL-6 response in rabbit serum is shown following booster immunization with GnRH II analog (|—|), or C-ase-1 (Δ---Δ).
[0026] FIG. 4 is a graph showing the effect of GnRH isoforms on leukocyte function. The effect of GnRH II and GnRH I on GM-CSF release from human leukocytes at 3 and 20 hours is compared.
[0027] FIG. 5A is a graph showing absorption of Applicant's GnRH II analog and circulating concentration of IL-8 where Applicant's analog was absorbed when administered vaginally to a baboon.
[0028] FIG. 5B is a graph showing absorption of Applicant's GnRH II analog and circulating concentration of IL-8 and IFNγ where Applicant's analog was absorbed when administered vaginally to a baboon.
[0029] FIG. 6A is a graph showing Applicant's GnRH II analog as an immune system antagonist, showing monocyte production of PGE after 3 hours of analog administration. Applicant's GnRH II analog induced PGE production at 10 −8 and 10 −7 M, but concomitant addition of GnRH II reversed the activity.
[0030] FIG. 6B is a graph showing Applicant's GnRH II analog as an immune system antagonist, showing monocyte production of TNFα after 3 hours of analog administration. Applicant's GnRH II analog induced TNFα production at 10 −8 and 10 −7 M, but concomitant addition of GnRH II reversed the activity.
[0031] FIG. 7 is a graph showing Applicant's GnRH II analog as an agonist, showing monocyte production of IL-10 after 24 hours incubation with an agonistic embodiment of Applicant's GnRH II analog. GM-CSF was also increased by the agonistic embodiment of Applicant's GnRH II analog.
[0032] FIG. 8 is a table showing binding affinity, normalized to GnRH II of D-Arg (6)-GnRH II-des-Gly(10)-ethylamide compared to D-Arg(6)-GnRH II-aza-Gly(10)-NH 2 in the placenta. Receptor binding affinity for D-Arg(6)-GnRH II-aza-Gly(10)-NH 2 was three times stronger than the binding affinity of ethylamide at the C-terminus.
[0033] FIG. 9A is a graph showing the inhibitory activity of D-Arg(6)-GnRH II-aza-Gly(10)-NH 2 on post proline peptidases.
[0034] FIG. 9B is a graph showing the inhibitory activity of D-Arg (6)-GnRH-des-Gly(10)-ethylamide on post proline peptidases.
[0035] FIG. 10 is a graph showing circulating levels of Applicant's analog in a monkey following vaginal delivery of the analog emulsed in a universal gel.
[0036] FIG. 11 shows localization of GnRH II receptor in immune tissues.
DETAILED DESCRIPTION OF THE INVENTION
[0037] GnRH II is the primary form of GnRH involved in the immune system. Disorders of the immune system are affected by GnRH II action. Because native GnRH II is subject to degradation in the blood, lymph, immune tissues and other tissues where immune cells and immune tissues are found, regulation of GnRH II action is best managed using stable analogs with high specificity and GnRH II affinity. The two major degradation molecules are (a) endopeptidases, which cleave GnRH II bond between the 5-6 positions, and (b) post-proline peptidases which attack the C-terminus, or tenth position of GnRH II.
[0038] Applicant has solved the problem of degradation of GnRH II within the immune system by creating novel GnRH II analogs that are modified in the sixth and tenth positions to resist attack and digestion by endopeptidases and post-proline peptidases while increasing GnRH II receptor affinity. Different embodiments of Applicant's analogs may act either as an agonist of GnRH II with acute direct action on the immune system or as an antagonist of GnRH II.
[0039] Applicant's GnRH II analogs are modified at the tenth position by an amino acid-amide substitution. Any suitable amino acid-amide substitution at the tenth position, including but not limited to aza-Gly 10 -NH 2 substitution, may be used making the sequence more stable in the circulation and in the immune system, immune tissues, lymph and other tissues where immune cells and immune tissues are found. Referring to FIGS. 9A and 9B , the advantage of substituting an amino acid-amide at position 10 over use of an ethylamide is shown. FIG. 9A shows the stability study of Applicant for one embodiment of Applicant's analog, D-Arg(6)-GnRH II-aza-Gly-NH 2 . FIG. 9B shows the stability study of Applicant for a D-Arg(6)-GnRH II-des-Gly(10)-ethylamide. D-Arg(6)-GnRH II-aza-Gly-NH 2 is shown in FIG. 9A to be fifty percent more stable than D-Arg(6)-GnRH I-des-Gly(10)-ethylamide.
[0040] Moreover, referring to FIG. 8 , the receptor binding affinity for GnRH analogs is shown. Substitution with an aza-Gly 10 -NH 2 shows receptor binding affinity almost three times more than an analog substituted with an ethylamide without an amino acid at position 10. Applicant's data shows that the substitution by Applicant at the tenth position with an amino acid-amide such as aza-Gly 10 -NH 2 resists degradation by post-proline peptidases present in the blood, lymph, immune tissues, and other tissues where immune cells and immune tissues are found, thus increasing stability therein.
[0041] The present GnRH II analogs have also been designed to inhibit endopeptidase degradation by having substitutions in the 5-6 position of the molecule. Endopeptidases in the human pituitary and blood degrade GnRH II at the 5-6 position. Applicant's GnRH II analogs substitute at the 6-position a D-Arg or other D-amino acid, including but not limited to D-Asn or D-Leu. Substitution of any D-amino acid will cause Applicant's analogs to resist degradation by endopeptidases. Any D-amino acid may be substituted at position 6 to reduce endopeptidase degradation.
[0042] However, the substitution of some D-amino acids cause Applicant's analogs to have an antagonistic affect on the human immune system, while other D-amino acid substitutions cause an agonistic affect on the immune system. In one embodiment of Applicant's analogs, Applicant substitutes D-Arg at position 6 (in addition to an amino acid-amide at position 10). Applicant has found that substitution of D-Arg and position 6 causes Applicant's analogs to have an antagonistic affect on the immune system.
[0043] Referring to FIGS. 6A and 6B , an example of the antagonistic effect of an embodiment of Applicant's analogs is disclosed. In FIGS. 6A and 6B , “AHA” represents the embodiment of Applicant's analogs D-Arg(6)-GnRH II-aza-Gly-NH 2 Monocyte production of PGE was shown to be affected antagonistically by Applicant's analog. PGE was measured after three hours of exposure to the analog in a dose range of 10 −10 to 10 −7 M (signified by the triangles in FIG. 6A ), and after three hours of exposure to a combination Applicant's analog and GnRH II at a dose of 10 −7 M (signified by the open circles in FIG. 6A ). Applicant's analog induced PGE production at 10 −8 and 10 −7 M. However, addition of GnRH II reversed the PGE activity.
[0044] Similarly, referring to FIG. 6B , monocyte production TNFα was shown to be affected antagonistically by Applicant's analog. TNFα was measured after three hours of exposure to the analog in a dose range of 10 −10 to 10 −7 M (signified by the solid squares in FIG. 6B ), and after three hours of exposure to a combination Applicant's analog and GnRH II at a dose of 10 −7 M (signified by the open squares in FIG. 6B ). Applicant's analog induced TNFα production at 10 −8 and 10 −7 M. However, addition of GnRH II reversed the TNFα activity.
[0045] Conversely, referring to FIG. 7 , monocyte production of IL-10 was shown to be affected agonistically. In FIG. 7 , “nIIA” represents the embodiment of Applicant's analogs D-Asn(6)-GnRH II aza-Gly-NH 2 . After twenty four hours of incubation with applicant's analog, production of IL-10 increased. GM-CSF was also increased by this analog.
[0046] The substitutions of Applicant's analogs at position 6 with a D-amino acid and the position 10 with an amino acid-amide must be made. Importantly, however, the native GnRH II backbone (i.e. the native GnRH II amino acids at positions 5, 7 and 8 of the GnRH II decapeptide) must be preserved in Applicant's analogs. The native GnRH II backbone and the substitutions at positions 6 and 10 enhance the binding of the GnRH II analogs to GnRH receptors in the immune system. The native GnRH II backbone of the analogs binds with high affinity to GnRH II receptors in the blood, lymph, immune tissues and other tissues where immune cells and immune tissues are found, while the substitutions at positions 6 and 10 resist degradation, resulting in a high stability of Applicant's analogs, while having high affinity binding to GnRH receptors. Using chimeras of GnRH I, GnRH II, or any other GnRH or GnRH like substance wherein portions of the backbone (positions 5, 7 and 8) of Applicant's analog are substituted with other corresponding amino acids from non GnRH II sources/forms of GnRH will diminish the GnRH II receptor binding capacity, and therefore are not acceptable for use as the analogs of the present invention. Said differently, to bind with high affinity directly to immune GnRH II receptors, Applicant's analog must originate from native GnRH II, and maintain the native GnRH II backbone at positions 5, 7 and 8.
[0047] Because of the stability and high-affinity binding of Applicant's GnRH II analogs, there are several applications of the analogs to the immune system. Applicant's GnRH II analogs may be used to stimulate or inhibit over-activity of the immune system to treat such immune disorders as allergies, asthma, graft versus host disease, immune deficiency diseases, autoimmune diseases, inflammation, tumor rejections and immune processes regulating implantation and pregnancy. Moreover, Applicant's analogs and antibodies of GnRH II, GnRH II receptors and GnRH II analogs can be used as a monitoring device to monitor the course of treatment of immune diseases, and to diagnose or detect expression, over expression, under expression of GnRH II receptors, or GnRH II peptide.
[0048] The following examples are included to demonstrate preferred embodiments of the invention. It should be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.
Example I
Design of Applicant's GnRH II Analogs
[0049] The present example outlines how analogs of GnRH II with increased activity in immune system tissues are designed.
[0050] Existing GnRH I analogs are designed for activity at the pituitary GnRH receptor and with extended stability in the circulation of individuals. Yet, the existing data indicate that the immune system tissues have a high affinity GnRH receptor which differs from that in the pituitary. In addition, the degradation of GnRH I is different in the immune system. Therefore, prior known pituitary GnRH I analogs have not been designed for use at immune system sites, and potent GnRH II analogs have not been designed for use at immune system sites. The present invention provides potent GnRH II analogs for use at immune systems sites.
[0051] Applicants GnRH II analogs were specifically designed to prevent degradation of the analog in immune system tissues. This allows for the maintenance of sufficient concentrations of analog to remain active when administered to the individual and to reach the immune system tissues. Analogs GnRH II sequences that show greater affinity for the immune system receptors than for the pituitary receptor, were modified to the tenth amino acid to aza-Gly 10 -NH 2 analog to make them resistant to degradation in the circulation and by peptidases. The GnRH II analogs were also modified at the 6 position using D-Arg, D-Asn, or D-Leu, making them resistant to degradation by the peptidase in blood, and were modified at the 10 position making them stable in blood and the immune system tissues. These analogs have increased binding to the immune system receptors and increased metabolic stability. See FIGS. 8 , 9 A and 9 B.
Example II
Localization of GnRH II in Tissues of the Immune System
[0052] Tissue of the immune system were examined for the presence of GnRH II in their cells. The presence of GnRH II demonstrated in immune cells and immune tissues of mammalian tissues that GnRH II isoforms are produced in the mammals and that they are present in the immune system.
[0053] Human tissues from the thymus, spleen and lymph nodes were fixed and sectioned and plated by sections on glass slides. The human tissues on the glass slides were incubated with anti-GnRH II ( 1/100) for 1 hour at RT. The tissues were then washed with phosphate buffered saline and anti-rabbit gamma globulin conjugated with biotin is incubated for 4 minutes at 55 C. The slide was rinsed in buffer followed by blocking of the endogenous peroxidase activity. Then streptavidin horse radish peroxidase was added and incubated for 4 minutes at 55 C. Stable diaminobenzidine (5 minutes at 55 C) was used to generate the signal. The slides were rinsed, mounted and read. The presence of GnRH II was localized via the DAB using microscopy. In the immune tissues examined, spleen, thymus and lymph node GnRH II was visualized. See FIG. 1 . Tissues such as atrium and liver were negative.
Example III
Stability Studies of GnRH Analogs
[0054] The present example demonstrated the stability of the GnRH II analogs. The enzymatic degradation of the GnRH II and its analog were studied using whole blood and plasma stability studies. A peptidase present in the immune system was used. GnRH II analogs were designed with these specific criteria in mind. The stability of these GnRH II analogs to the enzymatic activity of the peptidase and in immune system cells were examined.
[0055] The stability of most potent receptor-active GnRH II analogs in the presence of peptidase and immune system cells was identified. Each of these analogs was then studied for their ability to resist degradation over time of incubation with the immune system cells at 37° C. The reaction was stopped by freezing and the remaining GnRH I substrate, GnRH II substrate or non-mammalian analog was directly quantified by radioimmunoassay.
[0056] Studies using whole immune system cells were also performed. The enzymatic degradation of GnRH I was studied as described above, replacing peptidase with immune system homogenate. FIG. 2 is a graph showing stability of GnRH II analog in blood and plasma.
Example IV
Inhibition of Antibody Response
[0057] The production of antibodies is a function of the immune system. The ability of the immune system to respond to substances perceived as foreign by the body with the production of specific antibodies which will effect the inactivation of the substance is a function of the immune system. GnRH II or its analogs can regulate this activity in a mammal and this is a novel activity. The chronic administration of GnRH II activity can lead to the inhibition of the immune system's antibody response to a foreign substance.
[0058] The very stable, long acting GnRH II analog, D-Arg-GnRH II-aza-Gly-amide was conjugated to KLH and injected into rabbits to generate polyclonal antibodies. The titre of the antiserum was tested for binding to D-Arg-GnRH II-aza-Gly-amide and compared to the serum before treatment in each of four animals. This was compared to the generation of anti-serum using proteins other than GnRH II or its analogs. In three animals no antibodies were detected. In one of the four animals only an antibody of low titer was generated after four treatments, which inhibition occurred with continued immunization. FIG. 3 shows the antibody response for GnRH II analog and normal response titre and IL-6 response.
Example V
GnRH II and Methods for Treating Immune System Disorders
[0059] The present example discloses a method by which the present invention may be used to treat immune system disorders. As a proposed dose regimen, it is anticipated that a human between 100 lbs and 150 lbs would be administered about 10 nanogram to 1.0 gram of GnRH II analogs or their natural isoforms with or without a release regulating carrier. This would be expected to be effective for treating immune system disorders when administered.
[0060] It is also anticipated that pulsatile administration will cause stimulation of its activity while chronic administration can be used to down regulate receptors leading to inhibition of GnRH II activity. In some embodiments, the dosing regimen will comprise a pulsatile administration of the GnRH II analog over a 24-hour period, wherein the daily dosage is administered in relatively equal 1/24 th fractions. For example, where the daily dose is about 2.4 micrograms, the patient would be administered about 0.1 micrograms per hour over a 24-hour period. Such a daily pulsatile administration would create an environment in the patient sufficient to treat certain types of immune system disorders.
Example VI
Use of Antibodies Specific for GnRH II for Immune System Disorders
[0061] Referring to FIG. 1 , the present example demonstrates the utility for using the present invention GnRH II decapeptides to prepare antibodies that preferentially bind the GnRH II peptide sequences, or that bind the immune system GnRH II peptide or protein, Applicant's GnRH II analogs, or the GnRH receptors in the immune system. It is also anticipated that these antibodies may be used in a variety of screening assays. For example, these antibodies may be used to determine levels of GnRH II in a sample as an indicator molecule. The levels of such GnRH II may be used to monitor and follow a patient's immune system treatment. The antibodies may also be used to treat immunological disorders and diseases. The antibodies to GnRH II may be monoclonal or polyclonal antibodies.
[0062] These antibodies may be used for treatments that regulate the immune system via inhibiting the activity of GnRH II. Polyclonal antibodies may be created by standard immunization techniques, wherein the immunogen used will be native GnRH II. These peptides may be used either alone or together in a pharmaceutically acceptable adjuvant. The subject can be administered several doses of the GnRH II preparation, and the levels of the subject's antibody thereto monitored until an acceptable antibody level (titer) had been reached.
[0063] For the preparation of monoclonal antibodies, following standard techniques for the immunization of an animal, again using the peptides specific for GnRH II can be used. Once sufficiently high acceptable antibodies are reached (titer) in the animal, the spleen of the animal would be harvested, and then fused with an immortalized cell line, such as a cancer cell line, to produce a population of hybridoma cells. This hybridoma population of cells would then be screened for those that produce the highest amount of antibody that specifically bind the GnRH II. Such hybridoma cells would be selected, and then cultured. The antibody to GnRH II would then be collected from the media of the cell culture using techniques well know to those of skill in the art.
[0064] For purposes of the practice of preparing polyclonal and monoclonal antibody, the textbook Sambrook et al (1989) Molecular Cloning, A Laboratory Manual, 2 nd Ed., Cold Springs Harbor Laboratory, Cold Springs Harbor, N.Y., is specifically incorporated herein by reference. All of the compositions and methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure.
Example VII
GnRH II Analogs and Methods of Use in Treatment of Conditions of the Immune System
[0065] Due to the stability of Applicant's GnRH II analogs, in the blood and lymph, the presence of binding receptors in immune system tissues, and their biological activity in immune system tissues, Applicant's analogs can be used in the treatment of conditions of or regulation of the immune system and the tissues therein. Such treatment or regulation may be for allergies or asthma, graft-versus-host disease, immunodeficiency disorders, and autoimmune disorders.
[0066] Conventional methods, known to those of ordinary skill in the art of medicine, can be used to administer the pharmaceutical formulation(s) to the patient. Typically, the pharmaceutical formulation will be administered to the patient by intramuscular injection, subdermal pellet, or nasal spray. The pharmaceutical formulation(s) can also be administered via other conventional routes (e.g., oral, subcutaneous, intrapulmonary, transmucosal, intraperitoneal, sublingual, or intrathecal routes) by using standard methods. In addition, the pharmaceutical formulations can be administered to the patient via injection depot routes of administration such as by using 1, 3, or 6-month depot injectable or biodegradable materials and methods.
[0067] Referring to FIG. 5A and FIG. 5B , the absorption of Applicant's analog and circulating concentrations of IL-8 and IFNγ are shown. Baboons were vaginally administered Applicant's analog and measurements of GnRH II analog absorption and concentration levels of IL-8 and IFNγ were taken. Circulating concentration levels of IL-8 and IFNγ dramatically increased in response to administration of Applicant's analog.
[0068] Regardless of the route of administration, the therapeutic agent typically is administered at a daily dosage of 0.001 μg to 30 mg/kg of body weight of the patient. The pharmaceutical formulation can be administered in multiple doses per day, if desired, to achieve the total desired daily dose or as a long acting depot. The effectiveness of the method of treatment can be assessed by monitoring the patient for known signs or symptoms of the disorder.
[0069] The effectiveness of the method of treatment may also be assessed by following treatment with administration of a labeled GnRH II antibody. The antibody binding levels to either GnRH receptors or free, unbound GnRH II analog can be monitored to determine the effectiveness of the analog or its delivery.
Example VIII
Identification of the GnRH II Receptor in Human Immune System Tissues
[0070] Tissues of the immune system were examined for the presence of GnRH II receptors in their cells. The presence of GnRH II receptors in the tissues of humans has not been previously described. This present investigation demonstrated in immune cells of mammalian tissues that GnRH II receptors are produced in the mammals and that they are present in the immune system. See FIG. 11 .
[0071] Human tissues from the thymus, spleen and lymph nodes were fixed and sectioned and plated by sections on glass slides. The human tissues on the glass slides were incubated with anti-GnRH II ( 1/100) for 1 hour at RT. The tissues were then washed with phosphate buffered saline and anti-rabbit gamma globulin conjugated with biotin is incubated for 4 minutes at 55° C. The slide was rinsed in buffer followed by blocking of the endogenous peroxidase activity. Then streptavidin horse radish peroxidase was added and incubated for 4 minutes at 55° C. Stable diaminobenzidine (5 minutes at 55° C.) was used to generate the signal. The slides were rinsed, mounted and read. The presence of GnRH II receptor was localized via the DAB using microscopy. In the immune tissues examined, spleen, thymus and lymph node GnRH II receptor was visualized. Tissues such as atrium and liver were negative.
Example IX
Use of Antibodies Specific for GnRH II Receptor for Immune System Disorders
[0072] The antibodies specific for GnRH II receptor can be used to regulate immune system function. The present example demonstrates the utility for using the present invention GnRH II receptor to prepare antibodies that preferentially bind the GnRH receptor peptide sequences, or that bind the immune system GnRH receptor peptide or protein. It is anticipated that these GnRH II receptor antibodies may be used in a variety of screening assays. For example, these antibodies may be used to determine levels of GnRH II, or the GnRH receptor that binds GnRH II, in a sample as an indicator molecule. The levels of such GnRH may be used to monitor and follow a patient's immune system treatment. The antibodies to GnRH II may be monoclonal or polyclonal antibodies. Referring to FIG. 10 , circulating levels of Applicant's analog (“AIIA”) following vaginal delivery in a universal gel is shown. Vaginal absorption of Applicant's analog remained in the 70 PG/ml to 80 PG/ml range up to four hours post administration.
[0073] These antibodies may be used for treatments that regulate the immune system via inhibiting the GnRH II or the activity of the GnRH II receptor. Other antiserum may interact with the GnRH II receptor to stimulate its activity. Polyclonal antibodies may be created by standard immunization techniques, wherein the immunogen used will be peptides specific to the GnRH II receptor. These peptides may be used either alone or together in a pharmaceutically acceptable adjuvant. The animal, such as a rabbit, would be administered several doses of the peptide preparation, and the levels of the animal's antibody blood levels monitored until an acceptable antibody level (titer) had been reached.
[0074] For the preparation of monoclonal antibodies, one would follow standard techniques for the immunization of an animal, again using peptides specific to the GnRH II receptor. Once sufficiently high acceptable antibodies are reached (titer) in the animal, the spleen of the animal would be harvested, and then fused with an immortalized cell line, such as a cancer cell line, to produce a population of hybridoma cells. This hybridoma population of cells would then be screened for those that produce the highest amount of antibody that specifically bind the GnRH II receptor. Such hybridoma cells would be selected, and then cultured. The antibody to GnRH II receptor would then be collected from the media of the cell culture using techniques well known to those of skill in the art.
Example X
Receptor Binding Activity
[0075] Referring to FIG. 8 , the receptor binding activity of GnRH II and GnRH II analogs of the present invention are compared. There is a human GnRH II receptor which is distinct from the GnRH I receptor at the pituitary. Prior GnRH I analogs have been designed to increase activity at the pituitary GnRH I receptor and stability in the circulation of individuals. These GnRH I analogs do not demonstrate potent binding activity at the immune system's GnRH II receptors as they do at the pituitary's GnRH receptor. The present GnRH II analogs have been designed to interact with preference at the immune system GnRH II receptors and not the GnRH I receptor. They have also been designed to limit degradation by the immune system enzymes, present in lymphatic circulation. Binding activity of the newly synthesized GnRH II analogs has been studied in plasma. Referring to FIG. 8 , the receptor binding affinity for Applicant's analogs is compared to a GnRH II analog with a substitution of ethylamide at position 10. Applicant's analog (D-Arg (6)—GnRH II-aza-Gly (10)-amide) shows receptor binding affinity almost three times more than an analog substituted with an ethylamide without an amino acid at position 10.
[0076] The newly synthesized GnRH II analogs and other commercially available analogs have been used in receptor binding studies in plasma and enzyme stability study described here. On the basis of these studies, the most receptor potent and most enzyme-stable analogs have been chosen for further biopotency studies. GnRH receptors have been purified from the fractions from immune system tissues. The purification procedure for the GnRH receptor utilized ethanol precipitation of the receptor and not the GnRH. The remaining GnRH II binding assays activity using 125 I-D-Arg-GnRH II-Aza-Gly-NH 2 125 label and GnRH II have been performed. Receptors from two different tissues from the same type of immune system cells have been used to study each of these analogs. These data have enabled the inventor to predict the most potent GnRH II analog structure for the GnRH II receptor in the immune system, and assist in the design of even more potent analogs for the GnRH receptor.
[0077] In these studies, GnRH receptors have been purified from human immune system tissue after ethanol precipitation and extraction of GnRH in the supernatant. The binding affinity for the receptor free and containing supernatants were compared for each GnRH II or analog have been compared. Each study has been done using two different human immune system tissues.
Example XI
Activity of GnRH II or its Analogs on Immune System Tissues
[0078] Tissues of the immune system have been examined for the ability of their cells in vitro to respond to GnRH II in culture medium. The media from cell cultures of immune system tissues have been examined for the release of cytokine into the medium after incubation with and without GnRH II analog.
[0079] Cell cultures of human leukocytes tissues have been prepared. These cells have been cultured in the presence and absence of GnRH II and its analogs and GnRH I and its analogs at varying doses. The release of cytokines into the medium have been determined and compared for each form of GnRH studied. GnRH II and its analogs had greater activity on immune systems cytokines and GnRH II analog was the most active.
[0080] Applicant studied the effect of cytokines produced by T cells. Applicant found no effects of GnRH II, or Applicant's GnRH II analog on Interferon γ (INFγ), IL-4, IL-8 and IL-10 on the low production of these cytokines by any of these peptides using this system. Concentrations of 2×10 −9 to 2×10 −7 M at 1, 3 and 20 hours were studied.
[0081] Applicant also studied cytokine produced primarily by B cells and macrophages. Applicant observed that GnRH II analog inhibited Interleukin 12 (IL-12) after even one hour of treatment, which was still observed at 3 and 20 hours. The natural isoform of GnRH II also effected an inhibition at 3 hours while GnRH I increased IL-12 followed by a decrease at 20 hours using high dose of GnRH I. This is consistent with opposing activities followed by down regulation of the receptors with chronic high concentrations of the ligand.
[0082] Applicant also demonstrated that GnRH II at low dose is a potent stimulant of granulocyte macrophage colony stimulating factor, GM-CSF, while at high dose inhibits this cytokine as expected with down-regulation or the GnRH II receptor. The activity is observed at 3 hrs but not at 20 hours due to the limited stability of GnRH in biological fluids. FIG. 4 shows the effect of GnRH isoforms I and II on leukocyte function, specifically granulocyte/macrophage colony stimulating factors (GM-CSF) release from human leukocytes, at three hours and twenty hours. Using Applicant's GnRH II analog an inhibition of GM-CSF was clearly apparent after 20 hours of exposure. Monocyte production of IL-10 was shown to be affected agonistically. In FIG. 7 , after twenty four hours of incubation with applicant's analog, production of IL-10 increased. GM-CSF was also increased by this analog.
[0083] Applicant also demonstrated that Applicant's analog is an antagonist of GnRH II activity of PGE and TNFα. See FIGS. 6A and 6B . Monocyte production of PGE was shown to be affected antagonistically by Applicant's analog. PGE was measured after three hours of exposure to the analog in a dose range of 10 −10 to 10 −7 M (signified by the triangles in FIG. 6A ) and three hours of exposure to a combination Applicant's analog and GnRH II at a dose of 10 −7 M (signified by the open circles in FIG. 6A ). Applicant's analog induced PGE production at 10 −8 and 10 −7 M. However, addition of GnRH II reversed the PGE activity.
[0084] Similarly, monocyte production TNFα was shown to be affected antagonistically by Applicant's analog. TNFα was measured after three hours of exposure to the analog in a dose range of 10 −1 ° to 10 −7 M (signified by the solid squares in FIG. 6B ) and three hours of exposure to a combination Applicant's analog and GnRH II at a dose of 10 −7 M (signified by the open squares in FIG. 6B ). Applicant's analog induced TNFα production at 10 −8 and 10 −7 M. However, addition of GnRH II reversed the TNFα activity.
[0085] Applicant also demonstrated that monocyte production of IL-10 was shown to be affected agonistically. In FIG. 7 , “nIIA” represents the embodiment of Applicant's analogs D-Asn(6)-GnRH II aza-Gly-NH 2 . After twenty four hours of incubation with applicant's analog, production of IL-10 increased. GM-CSF was also increased by this analog.
[0086] While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the are that variations may be applied to the composition, methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. | Specially designed GnRH II analogs that are resistant to degradation by peptidases, are disclosed. The GnRH II analogs incorporate D-Arg, D-Leu, D-tBu-Ser, D-Trp, D-Asn or other active D amino acids at position 6 and aza-Gly-amide or other amino acid-amide at position 10. The D-Arg (6)—GnRH II-aza-Gly (10)-amide, D-Asn—GnRH II-aza-Gly (10)-amide, and D-Leu(6)—GnRH II-aza-Gly(10)-amide analogs are also provided, and demonstrate preferential binding to immune system GnRH receptors. These GnRH II analogs or their antibodies may be used in pharmaceutical preparations, and specifically in treatment of various immune system disorders. Antibodies to GnRH II, Applicant's GnRH TI analogs, and GnRH receptors can be used for the detection of GnRH II or the GnRH II analog or the GnRH II receptors as a diagnostic tool and/or to monitor treatment. | 2 |
FIELD OF THE INVENTION
The present application relates to video games and in particular relates to video games which are easily understood, requirement an element of skill and are competitive.
BACKGROUND OF THE INVENTION
Sophisticated video games that require specialized input devices to play, have proven very popular with children, adolescences and young adults. These games require a substantial degree of skill and have multiple levels with each level requiring additional expertise. Other computer video games are directed to an alternate world or game challenge where the player sets environmental conditions of the game and also selects or sets certain player characteristics or attributes. In some games the players work cooperatively for a common goal and in other games the players work against each other in a competitive environment.
Many of the more sophisticated games are played on home computers and are ongoing games played over a substantial period of time that need not be continuous.
Pay to play video arcade games are still available and range from the basic games to the more sophisticated games. In addition, there is a different market and consumer for countertop pay to play video games which are simplified games that are easy to play particularly using a touch screen as the input device. A host of different card games shooting games, etc. are available where the games typically have a relatively short time duration of from 1 to 3 minutes. These games are for entertainment purposes and are designed to be player friendly irrespective of the player's skill level. Such countertop games or console games are used in restaurants, bars, airports or other waiting areas and often function as a low cost time filler.
The players of these countertop video games are not typically game enthusiasts but may be somewhat older. The players enjoy a game having a competitive characteristic involving a degree of player skill but the game should also be easy to understand and execute. These games have very short learning curves and a player can then focus on the skill and the competitive aspect of the game to either play against himself for a personal best or against others in a competitive environment.
An important feature of a pay to play video game having such a short learning curve is the ability of the game to provide an experience to the player which is fulfilling in a relatively short period of time. Such an arrangement allows the entertainment device to be available to play more often or to execute a substantial number of games in a relatively short period of time. This is an important aspect as a pay to play game apparatus is often idle much of the time and usage may be very time dependent. There are often well known peak periods when it is important for the game apparatus to generate sufficient revenue to justify the cost of the device. It is also important that the price to play such games remain relatively low to encourage play and convince the customer they are receiving good value.
Many of these video game terminals have a host of different games available for play where the player may already have knowledge of a non computer version of the game such as a card game. Knowledge of pre-existing games available in other forms are also of assistance in overcoming a customers' potential reluctance or sensitivity to play a new game given that he may not be particularly successful. Furthermore, for many of these environments the consumer prefers a simplified video game for entertainment purposes during a relaxation or non-challenging escape period.
Some video game entertainment devices are avoided based on a potential consumers' fear that they will embarrass themselves due to a lack of knowledge of the details of the game or failure to understand or poorly implement the operation of the terminal. For this reason games which are relatively simple and easy to understand are often included in these video game entertainment devices, however the most popular games and revenue generating games have an element of competition and skill. Obviously these aspects have to be balanced with a game having a fast learning curve.
SUMMARY OF THE PRESENT INVENTION
A simplified video game for play on a pay to play computing device having a touch screen display and input device according to the present invention includes a series of timed events displayed on the touch screen. Each event produces a positive result or a negative result determined by the timing of a player's input signal relative to the event being displayed. The game for a positive result produces a series of screens depicting the actual positive result and displays a quantified measurement of the positive result. The game for a negative result produces a series of screens depicting the negative result. The event for a positive result requires a time duration greater than the time duration of a negative result. The game further includes the automatic initiation of the next event of the series of timed events after completion of one of said events until a total time period for the series of events has expired.
According to an aspect of the invention the series of events includes a first series of events and a bonus series of events. The first series of events is associated with a first round of the game and the first round has a fixed time period. The game includes a bonus round including the bonus series of events and having a fixed time period. The game provides a bonus round following a successful first round where a predetermined value has been exceeded. The predetermined value is compared to a cumulative total of at least some of the quantified measurements of events of the first round.
In a further aspect of the invention at least some of the quantified measurement of events of the first round includes at least the best 3 events of the first round.
In yet a further aspect of the invention at least some of the quantified measurement of events of the first round includes at least the best 5 events of the first round.
In a different aspect of the invention the ratio of total time for a positive result to the total time for a negative result is at least 3:2.
In a different aspect of the invention the ratio of total time for a positive result to the total time for a negative result is at least 2:1.
In a preferred aspect of the invention the time duration for a first round is less than 4 minutes.
In different aspect of the invention the time duration of a bonus round is less than 2 minutes.
In an aspect of the invention each event is associated with a falling object being displayed on the touch screen and a displayed character for attempting to strike the falling object to displace the falling object based the player's input controlling the timing of the strike of the falling object.
BRIEF DESCRIPTION OF THE DRAWINGS
The above as well as other advantages and features of the present invention will be described in greater detail according to the preferred embodiments of the present invention in which;
FIG. 1 is a screen shot from the game Gone Fishing during a play event;
FIG. 2 is a screen shot showing a particular result for one play event;
FIG. 3 is a screen shot showing a result of a different play event;
FIG. 4 is a screen shot providing instructions for the game;
FIG. 5 is a screen shot where the time for the particular game has expired and a cumulative score for various play events and the best result of an individual event of the game is posted;
FIG. 6 is a further screen shot providing the posting of the result for the particular game and a awarding a bonus round based on the results achieved;
FIG. 7 is an acknowledgement screen that the bonus round is about to start.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The screen of FIG. 1 is essentially the screen that will be shown on the touch screen video game device. The touch screen 2 includes a batter 4 , shown as a polar bear, with a baseball bat 6 for striking the jumping fish 8 . The jumping fish 8 jumps out of the hole in the ice 10 . The fish 8 achieves a substantial height above the hole 10 as indicated in the depiction of the touch screen 2 of FIG. 1 before falling by gravity towards the hole 10 . The jumping of the fish out of the hole 10 provides a warning to the player to be ready for striking of the fish on its subsequent downward travel.
The player playing the game is presented with a series of screens with the polar bear generally as indicated in FIG. 1 with a fish at various positions as it jumps from the hole in the ice 10 and falls toward the hole 10 . The player has an input area indicated as 12 in the form of a depiction of the head of the polar bear 4 . Touching of the nose portion 14 causes the polar bear 4 to swing the bat 6 . In the preferred embodiment 1 illustrated the input area corresponding to the nose position is quite specific. It is possible to merely allow player input by touching the touch screen anywhere.
Basically the swinging of the bat 6 is a timed event and is compared with the position of the jumping fish 8 to determine whether an impact will occur (a series of screens). Thus the player's input is solely the time of his touching input signal. There is no variation based on the position of the touch input. If an impact does occur the results of the impact are shown on the touch screen. The timing of the impact and the position of the fish as it falls toward the hole 10 , determines a certain trajectory of the jumping fish 8 and the eventual final location of the jumping fish, a distance from the hole in the ice 10 . Two results are shown in the touch screens of FIGS. 2 and 3 . In FIG. 2 the particular timing of the swing of the bat 6 has resulted in the jumping fish 8 taking on a relatively high trajectory from the bat. The fish when it impacts the snow packed surface shown as 14 is partially buried in the surface. There is no bounce or roll associated with this particular event and the distance of 132.3 meters is shown on the result sign 20 adjacent the buried fish 8 . The final distance is also shown in the center of the screen at the top indicated as 22 .
A slightly different result from a different event of the game is shown in FIG. 3 . In this case the fish 8 has achieved a distance of 183.2 meters from the hole in the ice 10 . The fish 8 is shown merely supported on the snow surface 14 and this particular fish due to the trajectory of the fish was initially bounced off the surface 14 and achieved a further distance. Depending upon the particular trajectory one or more bounces may occur and are shown to the player on the screen. The greatest distance from the hole 10 is achieved by a particular impact with the jumping fish determined by the timing of the player activating the swing of the bat relative to the position of the jumping fish as it is falling towards the hole 10 . Basically, this is merely a time relationship and certain results are predetermined and provided in a table. These results are then shown illustrating a particular trajectory of the fish the impact of the fish with the snow surface 14 and any bounce associated with that impact. The fish then comes to rest and a result is posted based on the calculated distance from the hole. Thus the jumping of the fish and the swinging of the bat and the result of the swinging of the bat represent a particular game event. If the timing of the input signal produces a miss the fish returns to the hole in the ice (i.e., a negative outcome) and a new game event is automatically commenced. If the timing associated with the swinging of the bat results in impact with the fish, then various screens are shown depicting the particular result. The results are then posted and after the results have been posted the next game event automatically occurs without further player input.
In this way the player is automatically brought to the next game event which commences with a fish jumping out of the hole 10 . If a successful hit occurs exclusively dictated by the timing of the players input signal certain screens are shown and the distance result is posted. The time required to show and post a positive outcome is somewhat longer than the time to show and post a negative outcome where impact with the fish does not occur. Certain screens are shown illustrating the non-impact with the fish followed by the next game event automatically commencing. The time required to confirm and show the negative impact is shorter than a successful result.
With this automatic commencing of the next game event, a non-skilled player and a skilled player are subject to a different number of events as the game has a certain time duration. A non-successful hit does result in some time elapsing from the total game time, however the next event occurs more quickly and provides the less skilled player with an additional opportunity to achieve a better result. Furthermore, a skilled player may indeed have produced a hit of the fish but this hit may not produced in a desirable result. For example, the screen of FIG. 2 with the result of 132.3 meters is a poor result given that under the particular game characteristics shown, a bonus round is provided if the player's best five events result in a cumulative distance greater than 1000 meters. This cumulative result of the best five events is shown at area 24 at the top of the screen. Area 26 shows the present all time best for the particular machine. Thus an undesirable positive result requires more time than a negative event and acts to provide further balance between skilled and non-skilled players.
FIG. 4 shows the particular initial screen providing instructions with respect to game play. Given that the play is relatively simple and easily understood this screen is quickly bypassed by hitting the OK button indicated as 30 .
FIG. 5 shows the result of a particular game of player number 1 where the total time for the game has expired. In this case the screen of FIG. 5 is displayed indicating that the time has expired. In addition, the player's best result is shown in area 40 and in this case the player achieved a distance of 212.5 meters. The player's total distance for his best five events are shown at the top of the screen and indicated as 895 meters at position 42 . This screen will be maintained for a short period of time and then the game will return to an attract mode or allow the player to play the game again or play a different game if credits are available on the machine.
FIG. 6 shows a slightly different result for the game. In this case the time for the game has expired however the player number 1 has achieved a total distance of 1006 meters indicated at 42 and 44 of FIG. 6 and his last result is indicated at a distance of 199.5 meters at area 46 . A bonus round is awarded if the player based on his best five events achieves a distance in excess of a certain number. In this case the bonus round is awarded at a distance of 1000 meters or more. The player has achieved five events that cumulatively exceed this amount and therefore the game displays the official results and awards a bonus round. As can be seen, two of the player's events are in excess of 200 meters and three are short of the 200 meters distance. This results in a total of 1006 meters and therefore the bonus round is awarded. The individual best results are shown on the screen of FIG. 6 as well. In this way, recognition of a good opening round is achieved and a total for his best five events is displayed for his own personal record and a prize is awarded allowing the player to participate the bonus round indicated in FIG. 7 .
The game is preferably set up such that it is not possible to achieve a bonus round from a bonus round. Basically, when the time for the bonus round expires the game ends. The game will post the results of the bonus round to provide feedback and recognition to the player.
This particular video game is simple to play in that the player merely touches the activation area 14 to solely determine the timing of a bat swing. The game then determines whether an impact occurs and displays the results. If a successful result occurs, i.e., impact with the jumping fish, the results of this impact are shown and a distance displayed. In the event that the timing of the swing does not result in a successful impact, this non-successful event is also displayed, i.e., the fish is shown returning to the hole however the next game event is automatically commenced within a shorter time period. In the event of a successful strike the results are displayed and once again after the results have been displayed the game automatically commences the next game event.
In this way, the game is played and continues and the player merely provides input regarding timing of the swinging of the bat. There is no input to initiate the next event as the game automatically determines this and executes the necessary steps. The play of the game is fast and the time of the game allows and effectively guarantees a relatively substantial number of events to occur. For example, given that this game is designed where the bonus round is determined on a players' best five events, the timing of the game can be set such that even if the player's timing of the swing of the bat results in all successful impacts with the fish the number of events for the game will be in excess of 10 for example. Thus the player has a significant number of events to attempt to provide five good results for achieving the bonus round.
In the event that a player is not as skilled, some of the events will be a failure to impact the fish and the game is designed to commence the next event more quickly and thus the player over the length of the game will have attempted more game events to the number of attempted where all events or most of the events were positive.
Although the game is extremely straightforward to understand, the degree of control or perceived control, i.e., player skill in achieving a good result, is relatively high. The automatic triggering of the next event assures a relatively quick pace and allows the player to concentrate on the timing of the bat swing.
It has been found that this game having a certain time duration, a certain time period for a particular game event, and the automatic initiation of the next game event based on the outcome of the previous particular event, is competitive and satisfying. Players of different experience can compete favorably with each other and also the players can compete against their own personal best. Furthermore, the game does not provide a technology challenge for the individual players. In particular, all players can quickly understand the game and play the game effectively without any substantial experience. Limiting the player's input to the timing of an input signal with the outcome then being predetermined has proven to be well accepted.
The game allows the player with a single input signal, to produce a great result. For example, the last swing of the bat prior to time running out could produce a personal or all time best result. Thus the game continues to hold the player's attention as there is always a chance to produce a rewarding outcome. A bonus round can also be awarded on the basis of a single event equaling or exceeding a certain level.
Although various preferred embodiments of the present invention have been described in detail, it will be appreciated by those skilled in the art that variations may be made without departing from the spirit of the invention or the scope of the appended claims. | A simplified video game includes a series of timed events where each event is capable of a positive or negative result based on the timing of player input signal. A positive result requires a time period greater than a negative result. The following event automatically is initiated after completion of the preceding event until a certain cumulative time period is reached. | 0 |
FIELD OF THE INVENTION
[0001] Embodiments of the present invention generally relate to containers and container end closures, and more specifically metallic beverage container end closures adapted for interconnection to a neck of a beverage container body.
BACKGROUND OF THE INVENTION
[0002] Containers, and more specifically metallic beverage containers, generally contain a neck or an upper portion that is adapted for interconnection to a metallic end closure. The container end closure is formed from a flat sheet of metallic material and generally includes a pull tab or other form of stay on tab (SOT). Beverage containers commonly store carbonated beverages, thus, both the container body and the container end closure are required to sustain internal pressures up to 90 psi without catastrophic failure or permanent deformation. Further, depending on the various conditions that the sealed container is exposed to heat, over fill, high CO2 content, vibration, etc., the internal pressure in a typical beverage container may at times exceed 90 psi. Thus, the container and end closure must be designed to resist deformation and failure while utilizing thin metallic materials.
[0003] Beverage containers are manufactured of thin and durable materials, such as aluminum, to decrease the overall cost of the manufacturing process and the weight of the finished product. It is also desirable to reduce the volume of material needed to fabricate the container end closure by optimizing the geometry and to more effectively improve buckle resistance and deformation. Accordingly, there exists a significant need for a durable beverage container end closure that can withstand high internal pressures associated with stored carbonated beverages and external forces applied during shipping, yet which is manufactured with durable, lightweight, reduced gage metallic materials with geometric configurations that reduce material requirements.
[0004] In an attempt to decrease material costs and improve strength, end closure engineers position the central panel proximate to the upper portion of the peripheral curl, which can result in other performance issues. More specifically, container end closures with a raised central panel height may experience problems associated with “tab-over-chime.” “Tab-over-chime” refers to a geometry where the pull tab is located above the height of the container, which creates stacking problems and thus potential damage during shipping and increased expenses. Thus, it is a challenge to design a container end closure that has improved geometry so that reduced gauge aluminum materials may be used while maintaining buckling and deformation performance of the end closure.
[0005] Previous attempts have been made to manufacture container end closures with unique geometric configuration in an attempt to provide material savings and improve strength. One example of a prior art beverage can end may be found in U.S. Pat. No. 7,100,789 to Nguyen et al., which is incorporated by reference in its entirety. Nguyen discloses a beverage container end closure that utilizes less material and has a chuck wall with improved buckle strength attributed to an inwardly oriented concave arch with a radius of curvature between about 0.015 inches and 0.080 inches. Container end closures that employ other unique geometries are disclosed in U.S. Pat. Nos. 7,506,779; 5,685,189; 6,460,723; 6,968,724 and U.S. Patent Application Publication Nos. 2002/015807 and 2005/0029269, which are each incorporated herein by reference.
[0006] The following disclosure describes an improved container end closure that is adapted for interconnection to a container body and that employs countersink and chuck wall geometry that decreases material costs while maintaining or improving performance.
SUMMARY OF THE INVENTION
[0007] It is thus one aspect of various embodiments of the present invention to provide a metallic container end closure with a novel geometry that can withstand significant internal pressures at times exceeding 90 psi, yet saves material costs. Although the end closures described herein generally apply to beverage containers for carbonated beverages, it should be appreciated by one skilled in the art that various aspects of the invention may be used for any type of container. In one embodiment of the present invention, these attributes are achieved by providing a countersink with an inner panel wall and an outer panel wall that are not parallel or slightly offset to a normal axis that passes through a horizontal plane of a substantially horizontal central panel. For example, one embodiment has an outer panel wall of the countersink that is interconnected to a lower portion of the chuck wall at an angle of about 21 degrees to define an outwardly disposed wall portion, and an inner panel wall, which is substantially parallel to the outer panel wall.
[0008] It is a further aspect of the present invention to provide a container end closure with an inner panel wall oriented outwardly away from the normal axis of the central panel. In one embodiment, the inner panel wall is disposed at an angle between about 20° and 30° from the normal axis of the center panel. In a preferred embodiment, the inner panel wall is disposed at angle between about 24° and 26° from the normal axis. In a more preferred embodiment, the inner panel wall is disposed at angle of approximately 25° from the normal axis.
[0009] In another aspect of the present invention, a method for forming a beverage can end closure is provided, wherein the container end closure is provided with a countersink radius of no greater than about 0.015 inches, and which is generally positioned at a depth no greater than about 0.084 inches from the central panel. Furthermore, the method forms a metallic end closure with a container having both inner and outer panel walls that are oriented outwardly from a vertical plane, and which utilizes a “reforming” process that alters the original geometry of the end closure or “shell.”
[0010] In another aspect of the present invention, a container end closure is provided that is manufactured with conventional manufacturing equipment. Thus, existing and well-known manufacturing equipment and processes can be implemented to produce an improved beverage can container end closure as contemplated herein. In another embodiment standard punches and dies used in container manufacturing industry are utilized. After the end closure is initially formed, a “reforming” process is performed to alter the geometry of the container end closure.
[0011] It is another related aspect of the present invention to provide a beverage container end closure that saves material costs by reducing the size of the blank material and/or utilizing thinner materials that have improved aluminum alloy properties. Thus, the integrity and strength of the beverage can end closure is not compromised, material costs are significantly reduced, and/or improved material properties are provided.
[0012] It is thus one embodiment of the present invention to provide a container end closure adapted for interconnection to a container body, comprising: a peripheral curl adapted for interconnection to a side wall of the container body; a chuck wall interconnected to said peripheral curl and extending downwardly at an angle of at least about 8 degrees as measured from a vertical plane; an outer panel wall interconnected to the lower portion of the chuck wall, said outer panel wall being angled about 8 degrees relative to the vertical plane in an outward direction away from a central longitudinal axis of the container; a countersink interconnected to a lower portion of said outer panel wall and having a radius of curvature less than about 0.017 inches; an inner panel wall interconnected to said countersink and extending upwardly at an angle of between about 15 degrees and 30 degrees as measured from the vertical plane; a central panel interconnected to an upper end of said inner panel wall and raised above a lowermost portion of said countersink at least about 0.084 inches.
[0013] It is yet another aspect of the present invention to provide a container end closure, comprising: a circular end wall adapted for interconnection to a side wall of a container; a chuck wall integrally interconnected to said circular end wall and extending downwardly, said chuck wall also interconnected to an outer panel wall; a countersink interconnected to a lower portion of said chuck wall and a lower portion of an inner panel wall and having a radius of curvature less than about 0.017 inches, said inner panel wall being outwardly angled about 25° relative to a vertical plane; and a central panel interconnected to an upper end of said inner panel wall and raised above a lowermost portion of said countersink no greater than about 0.084 inches.
[0014] It is still yet another aspect of the present invention to provide a method of manufacturing a metallic end closure, comprising: providing a preformed metallic end closure comprised of: a peripheral curl and a chuck wall extending downwardly therefrom at an angle of at least about 13 degrees as measured from a vertical plane, a countersink having an inner panel wall and an outer panel wall, and a central panel interconnected to an upper end of said inner panel wall; providing a reforming tool which generally comprises an upper cap and a lower cap that provides pressure to deform said metallic end closure, said countersink being held in place by at least one lower key ring; reforming said preformed metallic end closure by: engaging said central panel with said upper cap; engaging an underside of said central panel with a lower insert, said lower insert engaging with a lower retainer via a plurality of springs; contacting an outer surface of said upper cap with said chuck wall; contacting said countersink with said at least one lower key ring; moving said upper cap adjacent to said lower insert; and bringing an outer surface of said lower retainer in contact with said inner panel wall to deflect the inner panel wall, where said inner panel wall is deflected outwardly with respect to an axis perpendicular to said central panel.
[0015] The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detailed Description, particularly when taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The accompanying drawings, which are incorporated herein, and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these inventions.
[0017] FIG. 1 is a cross-sectional view of a prior art container end closure;
[0018] FIG. 2 is a detailed view of FIG. 1 , showing the countersink portion, chuck, wall and inner and outer wall portion in more detail;
[0019] FIG. 3 is a cross-section of a container end closure depicting one embodiment of the present invention;
[0020] FIG. 4 is a detailed view of the countersink and chuck wall of FIG. 3 ;
[0021] FIG. 5 is a detail of FIG. 3 , wherein dimensions associated with one embodiment of the present invention are provided;
[0022] FIG. 6 is an exploded perspective view of a reforming tool used to make one embodiment of the present invention;
[0023] FIG. 7 is a cross-sectional front elevation view of the countersink tool shown in
[0024] FIG. 6 ;
[0025] FIG. 8 is a cross-sectional view similar to that of FIG. 7 , wherein a container end closure is shown positioned within the tool;
[0026] FIG. 9 is a cross-sectional view of the countersinking tool wherein the container end closure has been reformed;
[0027] FIG. 10 is a detail view of FIG. 9 showing the container end closure positioned within the reforming tool prior to reforming;
[0028] FIG. 11 is a detail view of FIG. 9 showing the container end closure just prior to reforming;
[0029] FIG. 12 is a detail view of FIG. 9 showing the container end closure after reforming, and depicting the alteration of the countersink inner and outer panel walls; and
[0030] FIG. 13 is a cross sectional front elevation view of the container end closure of one embodiment of the present invention interconnected to a neck of a container body.
[0031] To assist in the understanding of one embodiment of the present invention the following list of components and associated numbering found in the drawings is provided herein:
[0000]
No.
Components
2
Container end closure
4
Container body
6
Peripheral curl
10
Chuck wall
14
Lower end
18
Upper end
22
Outer panel wall
26
Inner panel wall
30
Countersink
34
Central panel
38
Normal axis
42
Countersink forming tool
46
Upper cap
50
Lower cap
54
Lower key ring
58
Clamp ring
62
Upper surface
66
Underside
70
Lower insert
74
Lower retainer
78
Springs
82
Outer surface
90
Angled surface
94
Inner profile
[0032] It should be understood that the drawings are not necessarily to scale, and various dimensions may be altered. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.
DETAILED DESCRIPTION
[0033] Referring now to FIGS. 1 and 2 , a prior art container end closure 2 is shown. Container end closures 2 are typically comprised of a peripheral curl 6 that is adapted for interconnection to an upper edge of a neck of a container body 4 (See FIG. 13 ) in a double seaming process. The peripheral curl 6 is interconnected to a chuck wall 10 that is angled downward and inwardly toward a central longitudinal axis of the container body. Often, the chuck wall will have more than one angle as disclosed in U.S. Pat. No. 6,460,723. A lower end 14 of the chuck wall 10 is interconnected to an upper end 18 of an outer panel wall 22 that is interconnected to an inner panel wall 26 via a countersink 30 . The inner panel wall 26 is also interconnected to a central panel 34 that includes an opening member, for example such as a pull tab or other stay on tab or SOT.
[0034] Referring now to FIGS. 3-5 , the container end closure 2 of one embodiment of the present invention is shown. Here, a peripheral curl 6 is interconnected to a chuck wall 10 that is interconnected on a lower end to an outer panel wall. Again, it is contemplated that the chuck wall be made of two or any number of separate chuck walls, as disclosed generally in U.S. Pat. No. 6,460,723, and which may include any number of linear, or non-linear arcuate shaped segments. The lower end 64 of the chuck wall 10 is associated with the inner panel wall 26 by the countersink 30 . Although the inner panel wall 26 and the outer panel wall 22 are shown to be generally continuous, one skilled in the art will appreciate, however, that the inner panel wall 26 and the outer panel wall 22 may possess dimples or other radii integrated therein as taught by U.S. Pat. No. 7,506,779.
[0035] As shown in FIGS. 4 and 5 , the outer panel wall 22 in certain embodiments of the present invention is angled outwardly with respect to a normal axis 38 of the central panel (See FIG. 3 ). The chuck wall 10 is also angled in a different direction with respect to the normal axis 38 . Here, the chuck wall 10 is angled inwardly at least about 13 degrees from the normal axis 38 of the central panel 34 and the outer panel wall 22 is angled outwardly from the central panel wall 34 at an angle of at least about 8 degrees. This configuration creates a countersink 30 with an outward orientation. In addition, the inner panel wall 26 is angled (α) outwardly in one embodiment of the present invention at least about 25 degrees.
[0036] The outward orientation of the countersink as provided herein has the advantage of increasing buckle strength of the container end closure. The table below provides buckle strength test data. Here, “Control Ends” describe prior art or conventional container end closures and are compared to “reformed” container end closures of embodiments of the present invention. On average, buckle strength is increased by about 0.8 psi.
[0000]
Control Ends
Reformed Ends
Δ
Test
(psi)
(psi)
(psi)
1
96.6
99.0
2.4
2
97.7
98.4
0.7
3
97.1
100.4
3.3
4
98.6
98.9
0.3
5
97.3
101.0
3.7
6
97.3
100.0
2.7
7
98.2
99.8
1.6
8
98.6
100.5
1.9
9
97.4
100.2
2.8
10
97.2
99.7
2.5
11
97.7
98.7
1
12
96.8
99.5
2.7
13
97.9
98.6
0.7
14
98.6
95.1
−3.5
15
97.2
96.6
−0.6
16
97.8
96.9
−0.9
17
97.6
98.4
0.8
18
96.5
96.9
0.4
19
97.8
99.4
1.6
20
97.0
96.5
−0.5
21
98.0
97.2
−0.8
22
97.2
97.8
0.6
23
99.0
97.2
−1.8
24
96.6
100.3
3.7
25
98.1
96.0
−2.1
26
96.6
97.7
1.1
27
96.8
99.0
2.2
28
98.0
97.9
−0.1
29
97.4
97.2
−0.2
30
98.1
96.4
−1.7
Avg.
97.6
98.4
0.8
Dev.
0.672
1.542
High
99.0
101.0
Low
96.5
95.1
[0037] Referring now to FIGS. 6-12 , a countersink reforming tool 42 of one embodiment of the present invention is shown that is comprised of an upper cap 46 and a lower cap 50 that provides pressure to deform the container end 2 . The countersink 30 of the container end 2 is held in place by lower key rings 54 that are held in place by a clamp ring 58 . The upper surface 62 of the central panel 34 is contacted by the upper cap 46 and the underside 66 of the central panel 34 contacts a lower insert 70 . The lower insert 70 interacts with a lower retainer 74 via a plurality of springs 78 . The lower retainer 74 abuts the lower cap 50 .
[0038] During reforming operations, the end closure 2 is placed upon the lower insert 70 and the upper cap 46 is brought in contact with an upper surface 62 of the central panel 34 . An outer surface 82 of the upper cap 46 contacts the chuck wall 10 and the outer panel wall 22 of the countersink 30 is contacted by at least one lower key 54 , which is held in place by a clamp ring 58 . The lower insert 70 rests upon the plurality of springs 78 that are associated with the lower retainer 74 . The lower retainer 74 includes an angled surface 90 , which will contact an inward facing portion of the inner panel wall 26 .
[0039] During reforming, with particular reference to FIGS. 11 and 12 , the upper cap 46 is brought down upon the lower insert 70 . As the force acting on the upper cap 46 is increased, the lower insert 70 along with the container end closure 2 is brought to bear onto the outer surface 82 of the lower retainer 74 . This abutting relationship deflects the inner panel wall 26 outwardly as shown. The upper cap 46 will also help maintain 1) the radius between the central panel 34 and the inner panel wall 26 (about 0.015 inches in FIG. 5 ); 2) the angle of the outer panel wall 22 (about 13° in FIG. 5 ); and 3) the curl height (about 0.186 inches in FIG. 5 ). Furthermore, the lower key ring 54 includes an inner profile 94 that creates the distinct transition between the countersink and the outer panel wall as shown. As the inner panel wall 26 and associated countersink 30 is forced outwardly, the outer panel wall 22 is brought to bear against the profile 94 of the lower key ring 54 to create the outwardly deflected outer panel wall 22 . Deflecting the countersink 30 outwardly also reduces the countersink radius. In one embodiment the countersink radius is reduced from 0.015 inches to about 0.010 inches.
[0040] The lower key ring 54 defines a pivot point that deflects the countersink outwardly. In one trial the pivot point was set about 0.0216 inches below the central panel 34 and a 0.0500 inch improvement to “tab to chime” distance was achieved. Again, as used herein “tab to chime” refers to the distance from the central panel to the top of the peripheral curl. This pivot point position also increased the buckle strength of the container end closure by about 0.8 psi.
[0041] FIG. 13 is a cross-sectional view showing the container end closure 2 interconnected to the container body 4 after a double seaming operation has been conducted to interconnect the end closure with the neck of the container. For comparison, the outline of a standard container end closure is shown as well. The container end closure 2 of the present invention is shown with an inner panel wall of the countersink angled at least about 30 degrees outwardly from the normal axis of the central panel 38 , which is clearly distinct from the about 5 degree angulation of the inner panel wall of the prior art.
[0042] While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims. Further, the invention(s) described herein is capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. | The present invention describes a beverage container end closure that utilizes less material and has improved internal buckle strength based on the geometric configuration of a chuck wall, inner panel wall, outer panel wall, and central panel and that utilizes an outwardly oriented countersink. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation, under 35 U.S.C. §120, of copending international application No. PCT/EP2014/055721, filed Mar. 21, 2014, which designated the United States; this application also claims the priority, under 35 U.S.C. §119, of German patent application DE 10 2013 005 063.4, filed Mar. 22, 2013; the prior applications are herewith incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to an anti-trap protection method for an adjustable vehicle part and an associated anti-trap protection device.
For safety reasons, an anti-trap protection device is required for motor-driven adjusting devices for vehicle parts which are adjustable with respect to a fixed frame, in order to stop the motor operation, and reverse it if necessary, in a trapping situation in which an object or a body part is trapped while adjusting the vehicle part. In this case, the adjustable vehicle part is, for example, a vehicle window, a vehicle seat, a sliding door, a tailgate, etc. The body of the motor vehicle generally forms the fixed frame interacting with the adjustable vehicle part.
Customarily, a distinction is made in anti-trap protection devices between indirect and direct anti-trap protection. An indirect anti-trap protection device detects the trapping situation based on monitoring an operating variable of the servomotor driving the vehicle part, for example, an abnormal increase of the motor current or an abnormal decrease in the motor speed. A direct anti-trap protection device generally includes one or multiple sensors which detect a measured variable that is characteristic of the presence or absence of an obstacle in the adjustment path of the vehicle part, and an evaluation unit which decides, based on this measured variable, whether an obstacle is present in the opening area, and triggers appropriate countermeasures if necessary. In order to prevent the anti-trap protection device from stopping or reversing the adjustment of the vehicle part only in the case of direct contact of the obstacle with the vehicle part, non-contact sensors are often used in a direct anti-trap protection device which already detect an obstacle at a certain distance from the sensor. Non-contact sensors include in particular so-called capacitive proximity sensors.
A capacitive proximity sensor includes one or multiple electrodes via which an electric field is established along the adjustment path of the vehicle part. An obstacle in the adjustment path is detected by monitoring the capacitance of the electrode arrangement. Thus, use is made of the fact that an obstacle, in particular a human body part, influences the electric field generated by the sensor and thereby influences the measurable capacitance of the electrode arrangement. Alternatively to capacitive proximity sensors, other sensors functioning in a non-contact manner may be used, for example, optical sensors or ultrasonic sensors.
Under certain circumstances, a direct anti-trap protection device which is equipped with non-contact sensors may not correctly detect an obstacle in the adjustment path. This is the case, for example, with an optical sensor if the obstacle is transparent to the optical wavelength. On the other hand, a capacitive proximity sensor often does not detect obstacles which do not influence or only weakly influence the electric measuring field due to electrically neutral material properties, for example, obstacles made of electrically insulating material having low permittivity (dielectric constant).
Commonly assigned German published patent application DE 44 16 803 A1 describes an anti-trap protection device which combines direct anti-trap protection and indirect anti-trap protection. There, the direct anti-trap protection is based on a capacitance measurement, whereas the indirect anti-trap protection is based on a measurement of the motor speed. The goal is thus to provide redundancy for detecting the trapping situation if the direct or the indirect anti-trap protection fails. With the aid of this anti-trap protection device, a trapping situation may also be detected if the (functioning) direct anti-trap protection does not detect the obstacle in the adjustment path.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide an anti-trap protection device and an associated anti-trap protection method which overcome the above-mentioned and other disadvantages of the heretofore-known devices and methods of this general type and which provide for a simplified anti-trap protection device and method without decreasing the reliability with which a trapping situation is detected.
With the foregoing and other objects in view there is provided, in accordance with the invention, an anti-trap protection method for an adjustable vehicle part, the method comprising the following steps, to be performed continuously during an adjustment of the vehicle part:
acquiring a test value with the aid of a distance sensor;
performing a direct anti-trap protection test based on the test value by ascertaining whether an obstacle is detectable in the adjustment path of the vehicle part and, if necessary, stopping or reversing the adjustment; and
performing an indirect anti-trap protection test based on the same test value by ascertaining whether a motion of the vehicle part has slowed down in an irregular manner or has come to a standstill and, if necessary, stopping or reversing the adjustment.
In other words, in the anti-trap protection method according to the present invention for an adjustable vehicle part (hereinafter adjustment part), during the adjustment of the adjustment part, a test value is continuously ascertained with the aid of a distance sensor. Based on this test value, in a direct anti-trap protection test, it is initially ascertained whether an obstacle is detectable in the adjustment path of the adjustment part. If necessary, the adjustment of the adjustment part is stopped or reversed. Furthermore, according to the method, in an indirect anti-trap protection test based on the same test value, it is ascertained whether the motion of the adjustment part has slowed down in an irregular manner or has come to a standstill. If necessary, the adjustment of the adjustment part is stopped or reversed. A slowing down of the motion of the adjustment part is detected as “irregular” in particular if it occurs before reaching the final position of the adjustment path or a predefined stopping position of the ongoing adjustment operation and exceeds typical fluctuations in the adjustment speed.
The indirect anti-trap protection test is preferably carried out temporally in parallel (simultaneously) with, or having a slight time offset from, the direct anti-trap protection test.
The adjustment part is preferably a tailgate of the vehicle which is motor-driven in order to reversibly close the trunk opening. Alternatively, the adjustment part is a window, a sunroof, a vehicle seat, or a folding top of a convertible, each being motor-driven. Preferably, the anti-trap protection method is carried out during a closing motion of the adjustment part (in the case of a vehicle seat, when adjusting it downward, i.e., in the direction of the floor of the vehicle interior), since a particularly high risk of trapping exists in this situation. However, within the scope of the present invention, it is also conceivable in particular in the case of the tailgate to carry out the anti-trap protection method also during an opening motion of the tailgate. As a result, the tailgate striking an obstacle (for example, an adjacent vehicle, a parking garage wall) or trapping a person or an object on such an obstacle may be prevented in a simple manner.
The anti-trap protection method according to the present invention achieves a particularly high level of reliability with respect to the detection of a trapping situation, in other words, a particularly low risk of error, by carrying out a direct anti-trap protection test redundantly with an indirect anti-trap protection test. The direct anti-trap protection test thus makes possible a particularly early detection of a trapping situation via the direct detection of the obstacle. In particular, in many cases, the trapping situation may be already proactively detected before the adjustment part actually exerts a considerable trapping force on the obstacle. The indirect anti-trap protection test also acts as an additional safeguard in that it also ensures the detection of trapping situations which are not detected in the direct anti-trap protection test due to unfavorable properties of the trapped object.
The fact that both anti-trap protection tests are based on the evaluation of the same test value thus makes possible a considerable simplification of the implementation of the method, since only a single distance sensor is required to ascertain the test value. An additional simplification of the implementation of the method is made possible in that intermediate results of the method, in particular when calculating the test value, may be used for both anti-trap protection tests, so that these intermediate results must be calculated only one time.
In order to be able to differentiate simply and reliably between a “direct trapping situation” (i.e., an irregular profile of the test value which is caused directly by the presence of an obstacle in the adjustment path) and an “indirect trapping situation” (i.e., an irregular profile of the test value which is caused indirectly by the influence of the obstacle on the motion of the adjustment part) based on the same test value, the test value is preferably compared with a reference value which is in particular predefined as a function of time, this reference value reproducing the profile of the test value to be expected during trouble-free operation, i.e., when the trapping situation does not exist. During the course of the direct anti-trap protection test, the adjustment is stopped or reversed if the test value has a time dependence which is significantly stronger than the reference value according to stored criteria. During the course of the indirect anti-trap protection test, however, the adjustment is stopped or reversed if the test value has a time dependence which is significantly weaker than the reference value according to stored criteria. Preferably, threshold value comparisons, which are described in greater detail below, are used as criteria for the comparison of the time dependence of the test value with the time dependence of the reference value. Within the scope of the present invention, it is also conceivable that the reference value is predefined in a path-dependent manner. In this case, the path dependence of the reference value for carrying out the direct and indirect anti-trap protection tests is converted into a time dependence.
The method variant described above is based on the discovery that on the one hand, an indirect trapping situation always results in a reduction of the time dependence of the signals output by a distance sensor (and thus the test value derived from it), particularly as the ambient conditions of the distance sensor also always change more slowly with the trapping situation-dependent slowing down of the adjustment part.
On the other hand, an obstacle situated in the adjustment path of the adjustment part always forms the nearest object which is detectable by the distance sensor. Therefore, if the obstacle is directly detectable by the distance sensor, the introduction of the obstacle into the adjustment path must, as is known, always result in a greater time dependence of the test value than would be expected in the trouble-free case, particularly as the distance measured by the distance sensor is necessarily shortened by the obstacle.
Within the scope of the present invention, the relationship of the test value to the signal of the distance sensor may generally be defined in many different ways. Preferably, the signal of the distance sensor is used unchanged as the test value. However, within the scope of the present invention, it is also conceivable to derive the test value from the signal of the distance sensor according to a linear or non-linear relationship. For example, within the scope of the present invention, the test value could have a logarithmic, exponential, or polynomial (i.e., quadratic, cubic, etc.) relationship to the signal of the distance sensor.
The test value is preferably correlated running in the same direction or in the opposite direction to the distance measured by the distance sensor. “Correlation running the same direction” refers to a relationship of the test value to the measured distance in which the test value changes in the same direction as the distance, in which the test value thus becomes larger with increasing distance and smaller with decreasing distance. On the other hand, “correlation running in the opposite direction” refers to a relationship of the test value to the measured distance in which the test value changes in the opposite direction to the distance, in which the test value thus becomes smaller with increasing distance and larger with decreasing distance.
Alternatively to this, within the scope of the present invention, the test value may also be correlated running in the same direction or in the opposite direction to the temporal change, in particular a time-delayed (moving-averaged) derivative of the distance measured by the distance sensor. “Correlation running in the same direction and in the opposite direction” refers to a change of the test value running in the same direction or the opposite direction to the change in distance.
In any case, the reference value is adapted to each definition of the test value in such a way that it corresponds to the profile of the test value to be expected in trouble-free operation.
In one preferred embodiment of the method, the reference value is defined in such a way that it has a magnitude which decreases over time. In this case, in the direct anti-trap protection test, the adjustment is stopped or reversed if the test value falls below the reference value by a first threshold value. On the other hand, in the indirect anti-trap protection test, the adjustment is stopped or reversed if the test value exceeds the reference value by a second threshold value.
Alternatively to this, the reference value is defined in such a way that it has a magnitude which increases over time. In this case, in the direct anti-trap protection test, the adjustment is stopped or reversed if the test value exceeds the reference value by a first threshold value. On the other hand, in the indirect anti-trap protection test, the adjustment is stopped or reversed if the test value falls below the reference value by a second threshold value.
The first threshold value and the second threshold value may in both cases be set independently of each other to equal or different values.
Within the scope of the present invention, the reference value may be ascertained once in test runs of the adjustment of the adjustment part and unchangeably stored in a memory module for carrying out the anti-trap protection method. Preferably, however, the reference value is continuously taught-in during trouble-free operation and is thus updated with variable ambient conditions if necessary. As a result of this teach-in process, it is, for example, possible to take into account influences which variably influence the adjustment motion over the service life of the adjustment part, for example, temperature and aging of the adjustment mechanism.
Here and below, “anti-trap protection device” generally refers to a device for carrying out an anti-trap protection method. The anti-trap protection device according to the present invention includes an anti-trap protection control unit (hereinafter control unit), which is configured in terms of circuitry or programming to automatically carry out the anti-trap protection method according to the present invention, in particular in one of the specific embodiments described above.
Within the scope of the present invention, the control unit may be designed as a non-programmable electronic circuit and, for example, may be integrated into a controller of a servomotor driving the vehicle part. However, within the scope of the present invention, the control unit may also be formed by a microcontroller in which the functionality for carrying out the anti-trap protection method according to the present invention is implemented in the form of a software module. This software module may in particular form an integral part of a comprehensive control software program (firmware) of the controller of the servomotor.
In one preferred embodiment, the distance sensor is a capacitive proximity sensor. This proximity sensor preferably includes an electrode arrangement including at least one transmitting electrode and one receiving electrode which are preferably situated next to each other on the adjustment part or opposite to it on the vehicle frame along the adjustment path. The electrode arrangement is in particular situated on the adjustment part (the vehicle frame) in such a way that an electric measuring field is emitted from it in the direction of the adjustment path to be covered. The approach of a capacitively conductive and grounded object (for example, a body part) into the electric measuring field results in a reduction of the capacitance measured between the two electrodes.
Alternatively, within the scope of the present invention, it is also conceivable to arrange the, or each, transmitting electrode and the, or each, receiving electrode in juxtaposition on the vehicle frame and the adjustment part. Furthermore, within the scope of the present invention, the electrode arrangement of the distance sensor may also include only one electrode or multiple electrodes of the same type, with the aid of which the capacitance to ground, for example, the grounded vehicle frame, is measured.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in anti-trap protection for an adjustable vehicle part, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 shows a schematic side view of the rear of a vehicle including an adjustable vehicle part which is equipped with an anti-trap protection device;
FIG. 2 shows a schematic block diagram of the anti-trap protection device; and
FIG. 3 shows a schematic diagram of a typical profile of a test value ascertained by the anti-trap protection device and two threshold values for the indirect and direct detection of a trapping situation.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown a schematic illustration of the rear 1 of a motor vehicle. A tailgate 2 is pivotally hinged on an upper edge 3 on the rear 1 . The tailgate 2 is an adjustable vehicle part which is provided for reversibly closing a trunk opening 4 situated in the area of the rear 1 . For this purpose, the tailgate 2 is pivotable between a closed position and an open position along an adjustment path X which approximately describes a quarter circle.
The tailgate 2 is motor-driven for adjustment by an adjustment unit 5 . For this purpose, the adjustment unit 5 includes, in a manner not shown in detail, an electric motor and a gear which is subordinate to the electric motor, with the aid of which an adjusting force is transmitted to the tailgate 2 via a lever arm 6 .
In order to prevent an obstacle, for example, a body part of a person or another object, from being trapped between the tailgate 2 and the vehicle frame 7 bordering the trunk opening 4 when closing the tailgate 2 , i.e., when moving from the open position to the closed position, an anti-trap protection device is associated with the adjustment unit 5 . The anti-trap protection device includes an anti-trap protection control unit (hereinafter control unit 8 ) and a capacitive distance sensor 9 . The distance sensor 9 is connected to the control unit 8 using signal transmission technology via a sensor line 10 .
When closing the tailgate 2 , the control unit 8 is configured to detect an obstacle between the tailgate 2 and the vehicle frame 7 by carrying out an anti-trap protection method which is described in greater detail below, and to stop or reverse the motor of the adjustment unit 5 if necessary. For this purpose, the control unit 8 is connected to the adjustment unit 5 via a control line 11 .
FIG. 2 schematically depicts the anti-trap protection device in greater detail. For measuring the distance between the tailgate 2 and the vehicle frame 7 , or the obstacle which may possibly present, the capacitive distance sensor 9 includes a transmitting electrode 14 and a receiving electrode 16 which are situated next to each other on the tailgate 2 . By applying a voltage, an alternating electric field (i.e., an electric field in which the field strength periodically changes signs), referred to as a measuring field 18 , is established between the transmitting electrode 14 and the receiving electrode 16 . The transmitting electrode 14 and the receiving electrode 16 are situated on the tailgate 2 in such a way that the measuring field 18 is emitted in the closing direction 20 of the adjustment path X, i.e., in the direction of the vehicle frame 7 . The transmitting electrode 14 and the receiving electrode 16 thus form an electric capacitor having a capacitance C. The capacitance C is detected by the distance sensor 9 and fed to the control unit 8 via the sensor line 10 .
If electrically conductive and grounded material reaches the range of the measuring field 18 , the measuring field 18 interacts with this material, whereby the capacitance C of the distance sensor 9 is reduced (see FIG. 3 ). In the alternating field emitted by the distance sensor 9 , both the vehicle frame 7 and the human body act as an electrically conductive and grounded material. On the other hand, electrically insulating material having low permittivity, for example, dry wood, interacts only weakly with the measuring field 18 . An obstacle which is made up of such a material is thus “invisible” to the distance sensor 9 and is thus not directly detectable.
In order nonetheless to be able to prevent such an obstacle which is “invisible” to the capacitive distance sensor 9 from being trapped between the tailgate 2 and the vehicle frame 7 , the temporal profile of the capacitance C (capacitance profile C(t)) is checked by the control unit 8 as a test value for a direct trapping situation in a direct anti-trap protection test 22 and for an indirect trapping situation in an indirect anti-trap protection test 24 .
A “direct trapping situation” exists if an obstacle which is situated in the adjustment path X between the tailgate 2 and the vehicle frame 7 is directly detected by the control unit 8 , without direct contact with the tailgate 2 . In contrast, an “indirect trapping situation” exists if an obstacle which is “invisible” to the distance sensor 9 is trapped between the tailgate 2 and the vehicle frame 7 and is only indirectly detected by the control unit 8 based on the resulting irregularly stopping tailgate motion.
When detecting a direct trapping situation as well as when detecting an indirect trapping situation, a stop signal H is output to the adjustment unit 5 via a triggering unit 26 of the control unit 8 , on the basis of which the adjustment motion is stopped or reversed.
Referring now to FIG. 3 , we shall describe an anti-trap protection method carried out by the control unit 8 in greater detail based on a diagram in which the profile of the capacitance C is plotted over time t. During trouble-free operation, i.e., when a trapping situation does not exist, the measured capacitance profile C(t) corresponds to a reference profile C R (t) of a reference value C R , which is plotted by a solid line in FIG. 3 . The reference profile C R (t) is taught in by the control unit 8 during the ongoing trouble-free operation of the adjustment unit 5 , the reference value C R preferably being averaged over multiple previous adjustment operations. In order to achieve a repeatability of the adjustment operations which is as high as possible, the adjustment motion of the tailgate 2 is preferably regulated to a predefined speed profile via a control device of the adjustment unit 5 .
The reference value C R thus describes the value to be expected of the time-dependent capacitance C. The reference profile C R (t) thus specifically describes the decrease in capacitance C to be expected in a typical trouble-free closing operation of the tailgate 2 , which is based on the approach of the tailgate 2 to the conductive and grounded vehicle frame 7 .
An abrupt drop in the measured capacitance C is caused by an obstacle made of electrically conductive, grounded material, in particular by a human body, introduced between the tailgate 2 and the vehicle frame 7 , as is depicted by way of example in FIG. 3 as a capacitance profile C d (t). As a result, the capacitance profile C d (t) of the measured capacitance C decreases earlier or more steeply than the reference profile C R (t). The time dependence of the measured capacitance profile C d (t), which is thus stronger compared to the reference profile C R (t), is detected by the control unit 8 in the direct anti-trap protection test 22 in that the measured capacitance profile C d (t) falls below the reference profile C R (t) by a predefined threshold value ΔS 1 (t).
In the case of an indirect trapping situation, the tailgate motion is stopped in an irregular manner before reaching the closed position by the obstacle, which is invisible to the distance sensor 9 in this case. As a result, the distance between the distance sensor 9 and the grounded vehicle frame 7 and the capacitance C which is correlated with it are constant over time. The corresponding profile of the capacitance C is depicted in FIG. 3 as a capacitance profile C i (t). The capacitance profile C i (t) therefore has a time dependence which is significantly weaker compared to the reference profile C R (t). This time dependence is detected by the control unit 8 in the indirect anti-trap protection test 24 in that the measured capacitance profile C i (t) exceeds the reference profile C R (t) by a predefined threshold value Δ S 2(t).
Specifically, within the scope of the direct anti-trap protection test 22 , the control unit 8 continuously tests the condition
C ( t )< S 1 ( t )= C R ( t )−Δ S 1 ( t ). Equ. 1
The time coordinate in the capacitance profile C(t) in particular describes the elapsed time interval since the start of the ongoing adjustment operation. The zero point of the time coordinate of the reference profile C R (t) is calibrated taking into consideration the starting position of the tailgate 2 at the beginning of the adjustment operation, so that corresponding values in the capacitance profile C(t) and the reference profile C R (t) are always compared, even for adjustment operations starting from different positions. The threshold value ΔS 1 (t) is predefined as a function of time. Alternatively, this may, however, also be predefined as constant over time.
If the capacitance profile C(t) falls below the reference profile C R (t) by the threshold value ΔS 1 (t) (as depicted in FIG. 3 by way of example based on the value of the capacitance profile C d (t) at time t 1 ), the stop signal H is output to the adjustment unit 5 by the triggering unit 26 (see FIG. 2 ).
In parallel with the direct anti-trap protection test 22 , in an indirect anti-trap protection test 24 (see FIG. 2 ), the control unit 8 tests the condition
C ( t )> S 2 ( t )= C R ( t )+Δ S 2 ( t ). Equ. 2
If the capacitance profile C(t) exceeds the reference profile C R (t) by the threshold value ΔS 2 (t) (as depicted in FIG. 3 based on the value of the capacitance profile C i (t) at time t 2 ), the stop signal H is also output to the adjustment unit 5 by the triggering unit 26 (see FIG. 2 ). The threshold value ΔS 2 (t) is predefined as a function of time. Alternatively, this may, however, also be predefined as constant over time.
The control unit 8 thus uses the capacitance C as a test value for testing the direct as well as the indirect trapping situation. In an alternative embodiment of the control unit 8 , instead of the capacitance profile C(t), its time derivative averaged over time may also be used.
The threshold values ΔS 1 (t) and ΔS 2 (t) are chosen in such a way with respect to the taught-in reference profile C R (t) that a typical fluctuation range of the capacitance profile C(t) around the reference profile C R (t) is taken into account during operation, so that an erroneous triggering of the trapping situation is prevented. For example, fluctuations may occur due to temperature-dependent smooth running or sluggishness of the adjustment mechanism or due to weather-dependent influences on the measurement behavior of the distance sensor 9 .
The subject matter of the present invention is not limited to the exemplary embodiment described above. Rather, additional specific embodiments of the present invention may be derived from the above description by those skilled in the art.
The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention:
1 Rear 2 Tailgate 3 Upper edge 4 Trunk opening 5 Adjustment unit 6 Lever arm 7 Vehicle frame 8 (Anti-trap protection) control unit 9 Distance sensor 10 Sensor line 11 Control line 14 Transmitting electrode 16 Receiving electrode 18 Measuring field 20 Closing direction 22 (Direct) anti-trap protection test 24 (Indirect) anti-trap protection test 26 Triggering unit X Adjustment path C Capacitance C R Reference value C(t) Capacitance profile C R (t) Reference profile C d (t) Capacitance profile C i (t) Capacitance profile ΔS 1 (t) Threshold value ΔS 2 (t) Threshold value H Stop signal t Time t 1 Point in time t 2 Point in time | In the course of an easily implemented anti-trap protection method for an adjustable vehicle part, a test variable is continuously determined by way of a distance sensor during the adjustment of the vehicle part. A direct anti-trap protection test determines, based on the test variable, whether an obstacle is detectable in the adjustment path of the vehicle part. The adjustment is stopped or reversed if necessary. An indirect anti-trap protection test determines on the basis of the same test variable whether the movement of the vehicle part has slowed down irregularly or come to a stop, and the adjustment is stopped or reversed if necessary. An associated anti-trap protection device includes an anti-trap protection control unit, which is designed for automatically performing the method. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent application Ser. No. 14/507,983, filed on Oct. 7, 2014 which is currently under allowance, which is a continuation of U.S. patent application Ser. No. 13/892,792, filed on May 13, 2013, now U.S. Pat. No. 8,886,142, issued on Nov. 11, 2014, which is continuation of U.S. patent application Ser. No. 13/010,225, filed on Jan. 20, 2011, now U.S. Pat. No. 8,463,216, issued on Jun. 11, 2013, the disclosures of which are hereby incorporated by reference in their entireties for all purposes.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to radios for use in vehicles, and, more particularly, to improving signal reception quality in radios for use in vehicles.
[0004] 2. Description of the Related Art
[0005] Car radio reception quality is an important element of overall consumer vehicle satisfaction. Consequently, car original equipment manufacturers (OEMs) and suppliers perform extensive in-field testing in different countries to tweak the reception quality to suit each market segment.
[0006] Users listening to radios while driving near an AM or FM radio transmission tower may hear two types of distortion. A first type of distortion is front end overload distortion where transmission from a nearby station overwhelms the car radio's RF digital signal processing (DSP) receiver. Front end overload can lead to clipping distortion at the intermediate frequency analog-to-digital conversion chain process. A method to avoid this is to increase the attenuation at the front end and tweak the automatic gain control (AGC) that is prior to the analog-to-digital conversion (ADC) stage. However, since the overload affects the entire FM frequency range, the radio frequency (RF) designer is presented with the challenge of accommodating both strong and weak signal reception in such a scenario.
[0007] A second type of distortion is inter-modulation distortion arising from the use of non-linear devices. In the car radio environment, the non-linear devices are primarily the low noise amplifier (LNA) and the heterodyne mixer or mixers depending on whether the heterodyne mixing process is one step 10.7 MHz intermediate frequency or a lower frequency down-shifted base band intermediate frequency operating for low power devices using multi-stage down conversion. The current trend with respect to low power devices is to operate in base band intermediate frequency to ensure that the sampling rate is lower, as this translates into lower power utilization at the analog-to-digital conversion stage onwards.
[0008] Inter-modulation occurs when the input to a non-linear device (NLD) is composed of two or more frequencies of high signal levels and results in the creation of frequency artifacts that are a product of the inputs. These artifacts can result in either new ‘phantom’ stations (e.g., artifacts occur on frequencies where no valid station exists in the vicinity of the car radio) or overlap on a existing valid frequency. When a user tunes to the overlapped frequency, he hears audio modulations from the multiple audio sources including the valid radio station and the modulations arising from station frequencies involved in the creation of the artifacts themselves.
[0009] For example, third order inter-modulation can arise from the following permutations:
[0000] L*f 1 +/−M*f 2 +/−N*f 3, where f 1, f 2 and f 3 are distinct frequencies and L+M+N= 3, where L, M and N are integers (1)
[0000] Here f 1 , f 2 and f 3 are signals over 70 dBuV (which may be calibratable)
OR from
[0000] L*f 1 +/−M*f 2, where f 1, f 2 are distinct frequencies and L+M= 3 where L and M are integers (2)
[0000] Here f 1 and f 2 are signals over 70 dBuV (which may be calibratable)
[0010] While inter-modulation is typically caused by a car's proximity to strong transmission towers, other causes may originate from inside the car's passenger compartment through the use of powerful in-car FM transmitters which are used to stream audio from an external device (e.g., an iPod or external mp3 player) into a non-receivable FM radio station frequency so that the external audio source can be heard through the car speakers. These devices may output signal levels from 70 to 90 dBuV. Signals of a level exceeding 70 dBuV are considered strong signals and when mixed with other strong signals in the vicinity of the car, can lead to third order inter-modulation artifacts.
[0011] While inter-modulation distortion in the car radio can be of second order and third order types, the third order inter-modulation poses a bigger problem than second order inter-modulation. This is because second order inter-modulation can be typically filtered out using the band-pass filter. However, third order inter-modulation is harder to filter out as it lies very close to the center frequency of the frequency tuned by the radio head unit. A filter with characteristics steep enough to filter out third order inter-modulation but leave the tuned frequency intact is difficult to achieve.
[0012] Illustrated FIG. 1 is an example of typical prior art RF receiver topology that results in the creation of inter-modulation artifacts. The RF signal from the antenna goes through a low noise amplifier (LNA), which is a non-linear device, and then goes through a band-pass filter which tends to filter out frequencies outside the FM band. The next stage is the mixing with the local oscillator to provide the intermediate frequency. The mixer is also a non-linear device. The output product from the mixer passes through another filter stage to ensure that only the required intermediate frequency is output before the signal is digitally sampled at the RF analog to digital converter (ADC) and then again passes through an intermediate frequency (IF) filter.
[0013] FIG. 2 illustrates the characterization or mapping of the input power versus output power of a typical non-linear device. The plotted line 10 represents the third order inter-modulation characterization. The gain of the output inter-modulation product is based on the slope of line 10 . For Global A boards, for example, the third order inter-modulation is between 10 and 15 dBuV and is known to cause audio distortion.
[0014] Illustrated in FIG. 3 is an example expanded characterization of output power versus input power for a non-linear device. FIG. 3 illustrates a typical model that is used to characterize the level of artifacts created. Line 12 represents the third order inter-modulation characterization.
[0015] The level of expected inter-modulation is shown in FIG. 4 , which illustrates modeling of third order inter-modulation. The third order input intercept point (IIP 3 ) is in units dBm and is a function of AP from the input levels of the fundamental strong frequencies at the input to the non-linear device.
[0016] FIG. 5 illustrates the third order intercept point (IP 3 ) inter-modulation power increase for non-linear devices with no saturation. As shown in FIG. 5 , the effects of inter-modulation vary based on the RF design and the characteristics of the components used. If the system has no saturation, then the third order inter-modulation can be as high as the fundamental frequencies at the input of the non-linear device.
[0017] FIG. 6 also illustrates IP 3 inter-modulation power increase for non-linear devices with no saturation. As shown in FIG. 6 , the third order inter-modulation effects depend on the performance of the gain stages at the latter part of the RF chain. This is true because the gain value increases geometrically towards (G n ) at the end of the chain.
[0018] FIG. 7 illustrates a characterization of the problem posed by third order inter-modulation. FIG. 7 highlights the reason why it is difficult to filter out the third order inter-modulation artifacts. While the second order harmonics are outside the pass band, the third order inter-modulations such as 2f 1 −f 2 and 2f 2 −f 1 are very close to the fundamental frequencies f 1 and f 2 (where f 1 and f 2 are strong signals of 70 dBuV or above). Because of the difficulty in filtering the third order inter-modulations, this poses a serious reception problem.
[0019] Accordingly, what is neither anticipated nor obvious in view of the prior art is a method of sensing inter-modulation distortion and mitigating its effects on signal reception quality.
SUMMARY OF THE INVENTION
[0020] The present invention may provide a method of using known car radio hardware architecture in conjunction with a novel software algorithm to thereby sense and mitigate inter-modulation artifacts and improve the overall performance of the car radio reception quality.
[0021] There are several end applications contemplated for the present invention with respect to the car radio. A first end application is to improve single and dual tuner alternative frequency switch behavior. Global A radios have a test route which exhibits a classical use case: On Mount Taunus in Germany, there exists two strong transmitters operating at 102.5 MHz and 105.9 MHz. These two strong signals (over 90 dBuV) result in a third order inter-modulation product (2×102.5)−105.9=99.1 MHz. Also in the vicinity (2×96.7)−94.3=99.1 MHz, another intermodulation is produced on the same frequency. When the user is tuned to station SWR 1 and drives up the mountain, an unwanted alternative frequency (AF) switch occurs to the strongest station (99.1 MHz) which has good quality and yields a proper Program ID code prior to the switch. However when the radio switches to this station, the user hears distorted audio artifacts where there are audio products from three separate stations (SWR 1 +station operating 102.5 MHz and station operating 105.9 MHz). In the above scenario, with regards to audio quality, the reception quality can be improved if the radio switches to an alternate frequency that is of secondary signal quality rather than the strongest quality, and that is not an inter-modulation product, thus yielding better audio quality performance.
[0022] A second end application of the invention is radio data system (RDS) preset recall/digital audio broadcasting (DAB) FM link performance enhancement. Preset recall or DAB FM link to an RDS station involves tuning by Program ID code rather than frequency. Herein the radio checks all the best alternative frequencies associated with the Program ID code and tunes to the best alternative frequency with the criteria being signal quality and the frequency transmits the Program ID code. With inter-modulation at play the radio risks tuning to a station that is an inter-modulation product. This results in the end user tuning to a station whose audio quality is composed of the inter-modulating frequencies and the actual audio content.
[0023] A third end application of the invention is autoseek performance enhancement. A car radio parked or being driven near a transmission tower may need to ensure that it does not seek stops on inter-modulation tainted frequencies even if the quality of these stations are considered good and within limits with respect to field-strength levels, multipath, ultrasonic and frequency offset metrics.
[0024] A fourth end application of the invention is to optimize distortion artifacts during manual tune operation. In the event that the user especially wants to listen to a station frequency through direct tune or manual tune operation, the radio, upon detecting that the frequency has inter-modulation artifacts, can choose to adjust the automatic gain control to improve audio quality.
[0025] The present invention may provide a mechanism to detect inter-modulation in single tuner and dual tuner radios and utilize this apriori information in avoiding the inter-modulation artifacts. The inventive method may accommodate the case in which the car moves away from the strong signal transmitters, or when the in-car FM transmitters have been turned off. The invention may enable the car radio to recognize that inter-modulation artifacts are no longer present and thus adapt itself.
[0026] The inventive method may detect the inter-modulation and use this apriori information to improve the performance of a number of applications. Specifically, the method may improve RDS AF switching behavior in single and dual tuner radios by ensuring that the radio does not switch to a tainted inter-modulation frequency. The method may also improve RDS Preset recall performance by ensuring that the tune by PI code ensures that the alternative frequency picked for reception is not a frequency tainted by inter-modulation artifacts. The method may further improve auto-seek seek stop performance in the FM mode to ensure that seek stop does not occur at a frequency associated with an inter-modulation artifact.
[0027] In Europe, DAB FM link occurs when a user is tuned to a digital DAB station. When the bit error rate (BER) increases, the decoding of the MP 2 compressed audio stream becomes difficult for the DAB receiver. In such a circumstance, the radio typically falls back on the simulcast FM station frequency to produce audio. FM stations in Europe employ RDS which categories stations with a program ID code whereby multiple frequencies are associated with a single station. In such a case, a tune by PI operation of the present invention to trigger the DAB FM link may ensure that the final strongest alternative frequency picked for tune operation in the FM band is not an inter-modulation artifact.
[0028] The present invention may be applied to AF switching in either a single or double tuner environment. European countries embrace the full features set out by the RDS standard which is AF switching. The way this scheme works is that low power transmitters encompass the European FM landscape. A station operates under different frequencies whereby audio on all these alternate frequencies consists of simulcast audio and data information from the station.
[0029] A single tuner radio operating in this environment, when tuned to a RDS station, may receive the AF that the radio can switch to in case the currently tuned-to frequency fades in signal quality. Before an actual switch is done, the single tuner RDS radio may typically perform quality checks, such as for fieldstrength, multipath, adjacent channel energy, and frequency offset, for example. After the quality checks have been performed, and the AF is noted to be better than the currently tuned-to station frequency, the radio may switch over to this stronger AF after a mute operation and delve on this target station for a program ID code check. The program ID confirms that the station being switched to is transmitting the same audio as the most recently tuned-to station. This may result in mutes which can vary in time duration based on the time used for the PI wait time. The mute time duration may range between 500 ms and 1500 ms depending on the RDS block error rate, which may be affected by frequency offset errors, multi-path and/or adjacent channel activity, assuming the sampled signal is of good quality (e.g., 32 dBuV or above for field strength). If the PI code (a sixteen bit word termed “program identification code” and defined in the RBDS standard) matches the PI code of the last tuned-to station, then the AF switch occur, and an unmute of audio is performed. If the PI code does not match the sampled AF, then the radio switches back to the originally tuned-to station and unmutes. The latter is a partly failed AF switch attempt as the radio transmitter list of alternate frequencies is not fully correct because either these station frequencies are operating as regional variants, or a true case of co-channel situation exists such that the frequencies can carry different audio content.
[0030] When the PI code cannot be received, then the alternate frequency switch may be delayed.
[0031] Muted PI checks may be performed for single tuner variants. OEM customers require this program ID check partly to reduce the risk of potentially switching over to a different station (with different audio modulation) and are willing to tolerate the mute. However, in order to prevent too many mutes from occurring, what is referred to as a “trust timer” is used to perform an un-muted alternate frequency switch. The trust timer may minimize the number of audible mutes.
[0032] The way this scheme works is that after acquiring the PI code through a mute, typically a trust timer is set for the frequency. The trust timer is usually a counting up timer starting from 0 seconds (the time at which the PI code is received) to a maximum of 15 minutes. The way this trust timer helps in reducing the number of mutes is such that once a single tuner radio sets the trust timer, the radio can potentially switch over to this station frequency in what is termed an unmuted PI check (frequency is switched without muting the audio) during the valid duration of the trust timer as specified by the developer. The duration of the trust timer specified by the developer can vary based on the locality and proximity of the radio stations. This approach of using a trust timer may not work well, however, in certain FM landscapes where co-channel frequency exists, e.g., where a second station uses the same alternate frequency known to the radio. In this instance, an unmuted AF switch can result in what is termed a “wrong audio modulation” lasting from the time the AF switch occurs, the radio variant tunes to this new station, senses through the reception that the new station has the wrong PI code, and finally reacts by switching back to the original frequency. To prevent the software from using the sampled frequency, what may be referred to as a “disable timer” may be set.
[0033] In summary of the above limitations on the operation of a single tuner RDS radio, there may be mutes during a PI code switch. An unmuted AF switch based on the trust timer can reduce mutes but does not combat against wrong modulation in case frequencies are reused by different stations. Stations in Europe also operate as regional variant stations. Single tuner radio variants have these operational limitations because there is no luxury of a second tuner to perform background scanning and inaudible PI checks.
[0034] The method of the present invention adds a third degree of optimization by performing the PI check only for alternative frequencies that are presented to the car radio and that are not third order inter-modulation artifacts. The way such alternative frequencies may be sensed in a single tuner is through the use of information gathered in the frequency learn memory of the frequencies in the FM band.
[0035] The invention comprises, in one form thereof, a method of performing alternate frequency switching in a radio, including tuning the radio to a primary frequency. A candidate alternate frequency is identified. It is determined whether the candidate alternate frequency is a third order inter-modulation artifact. Tuning is switched from the primary frequency to the candidate alternate frequency only if it is determined in the determining step that the candidate alternate frequency is not a third order inter-modulation artifact.
[0036] The invention comprises, in another form thereof, a method of performing autoseek in a radio, including scanning a radio frequency band for a candidate frequency having a quality exceeding a threshold quality level. It is determined whether the candidate frequency is a third order inter-modulation artifact. The radio is tuned to the candidate frequency only if it is determined in the determining step that the candidate frequency is not a third order inter-modulation artifact.
[0037] The invention comprises, in yet another form thereof, a method of automatically tuning an FM radio to a frequency, including identifying a plurality of first frequencies within an FM band that have a signal quality above a threshold level. A plurality of second frequencies that are third order inter-modulation artifacts of the first frequencies are calculated. Tuning to the second frequencies is avoided.
[0038] An advantage of the present invention is that it prevents the radio from tuning to a third order inter-modulation artifact in autoseek, AF switching, and DAB FM Link operations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] The above-mentioned and other features and objects of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
[0040] FIG. 1 is a block diagram illustrating an example of typical prior art RF receiver topology that results in the creation of inter-modulation artifacts.
[0041] FIG. 2 is a plot of the input power versus output power of a typical non-linear device.
[0042] FIG. 3 is an example expanded plot of output power versus input power for a typical non-linear device.
[0043] FIG. 4 is a plot of frequency versus a level of expected third order inter-modulation.
[0044] FIG. 5 is a series of plots illustrating the third order intercept point (IP 3 ) inter-modulation power increase versus frequency for non-linear devices with no saturation.
[0045] FIG. 6 is a schematic illustration of IP 3 inter-modulation power increase for non-linear devices with no saturation.
[0046] FIG. 7 is an amplitude versus frequency plot of inter-modulation artifacts in a radio frequency signal.
[0047] FIG. 8 is a block diagram of one embodiment of a single tuner radio system of the present invention.
[0048] FIG. 9 is a timing diagram depicting muting during a neighbor frequency check according to the present invention.
[0049] FIG. 10 is a table depicting one embodiment of a frequency learn memory used to gather apriori information for the European market according to the invention.
[0050] FIG. 11 is a table depicting one embodiment of a frequency learn memory for the North American market according to the invention.
[0051] FIG. 12 is a block diagram of one embodiment of a dual tuner radio system of the present invention.
[0052] FIG. 13 is a block diagram of one embodiment of a dual tuner phase diversity system of the present invention.
[0053] FIG. 14 is a block diagram of one embodiment of a dual tuner external switched diversity system of the present invention.
DETAILED DESCRIPTION
[0054] The embodiments hereinafter disclosed are not intended to be exhaustive or 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 utilize its teachings.
[0055] In one embodiment, the method enables the radio to build up signal level metrics of frequencies in the FM band in a memory repository and then utilize the information using the formulae such as (1) and (2) below in identifying the artifact:
[0000] L*f 1 +/−M*f 2 +/−N*f 3, where f 1, f 2 and f 3 are distinct frequencies and L+M+N= 3, where L, M and N are integers (1)
[0000] OR from
[0000] L*f 1 +/−M*f 2, where f 1, f 2 are distinct frequencies and L+M= 3, where L and M are integers (2)
[0000] The way the information is updated in the repository memory area may vary between single and dual tuner.
[0056] Referring now to FIG. 8 , there is shown one embodiment of a single tuner radio system 20 of the present invention. Radio system 20 may include a microcontroller 22 which may be used to process user input. A digital signal processor (DSP) 24 may be used to provide audio demodulation of the air-borne intermediate frequency (IF) input signal. DSP 24 may also be used to provide quality information parameters to the main microcontroller 22 via a serial communication protocol such as I2C. The quality information parameters may include multipath, adjacent channel noise, FM frequency offset, FM modulation and field strength. The I2C channel may be a dedicated channel so that delays due to shared resource contentions are prevented. DSP 24 may rely on a Tuner IF Front End IC 26 to perform the front end RF demodulation and the gain control. Tuner IF Front End IC 26 may also output the Intermediate Frequency to DSP 24 where the Intermediate Frequency may be demodulated and processed. Tuner IF Front End IC 26 may further provide a gain to the IF (Intermediate Frequency) signal of up to 6 dBuV prior to forwarding the signal to DSP 24 . Communication between Tuner IF Front End IC 26 and DSP 24 , as indicated at 27 , may be via a serial communication protocol such as I2C, which may operate at 400 kbps.
[0057] An antenna system 28 may be communicatively coupled to Tuner IF Front End IC 26 . Antenna system 28 may be in the form of a passive mast, or an active mast of phase diversity, for example.
[0058] An AF sample line 29 and an AF hold line 31 provide an interface between DSP 24 and Tuner IF Front End IC 26 to coordinate a quick mute as described hereinbelow. A pause interrupt line 33 between DSP 24 and microcontroller 22 may be used to inform microcontroller 22 whenever a pause occurs.
[0059] DSP 24 may provide signal quality parameterization of demodulated tuner audio and may make it available to microcontroller 22 via a serial communication bus 30 . In one embodiment, serial communication bus 30 is in the form of a 400 kbps high speed I2C.
[0060] The signal parameterization may include field strength, multipath, FM frequency offset, FM modulation and ultrasonic noise. Field strength may give an indication of signal reception and may help determine whether the radio station has good signal coverage in the vicinity of the user. This field strength quality parameter may be applicable for both AM and FM modulation signal reception.
[0061] Although the signal can have high field strength, it can be subject to reflections which can arise from trees and tall building which reflect/deflect the signal. The multipath parameter may enable the level of multipath to be ascertained, and may affect reception quality. The multipath quality parameter may be more applicable to FM modulation signal reception than to AM because in AM reception the wavelength is wider.
[0062] With regard to the ultrasonic noise quality parameter, it sometimes happens that stations over-modulate their signal leading to adjacent channel interference. For example, in the U.S., FM frequencies are spaced apart 200 kHz. There can arise times in which an adjacent station over-modulates its signal past the 75 kHz modulation and beyond the 50 kHz guard band, which may result in the adjacent station being heard on the tuned-to station's frequency.
[0063] With regard to the FM modulation quality parameter, the detector may provide the amount of frequency deviation about the FM carrier center frequency. The amount of frequency deviation may be directly proportional to the audio content being played in the FM station. The typical modulation bounds of this detect is 75 kHz for North America and between 22.5 kHz and 40 kHz for Rest of World and Europe. The FM modulation quality parameter is discussed in more detail hereinbelow.
[0064] The quality parameter of FM frequency offset is a measure of misalignment between modulation and demodulation frequencies. The misalignment value is typically small. However, a large offset error in the form of a large misalignment value may signify strong adjacent channel presence. Alternatively, a large offset error in the form of a large misalignment value may signify that the transmitting station is a “pirate” station and is not operating exactly on its assigned frequency, but rather has an inherent offset error. This tends to occur in Italy.
[0065] A novel feature of the present invention is the sampling of FM signals while the user is listening to an FM signal as the current foreground source. The difficulty associated with performing the sensitivity check while in FM mode, especially in a single tuner environment, is that the tuner to which the listener is listening has to momentarily switch to another station, perform the quality check, and then re-tune to the listened-to station. The user is not able to listen to the station during the time period between the switching of the station and the re-tuning of the station. This interruption in the signal of the listened-to station may be perceptible by the user, and thus may be a source of annoyance to the user.
[0066] If the audio system is in compact disc (CD) mode or is using some other non-tuner source, the bandscan checks of the frequencies can be easily performed as the tuner can perform the checks without the checks being perceptible to the user since the user is listening to a non-tuner source. To be able to perform the checks in an imperceptible manner, the present invention may utilize a DSP including pause detection logic that is able to detect pauses (i.e., periods of silence or unvoiced activity) in the demodulated audio stream. In one embodiment, pause is detected by computing the number of zero crossings in a particular window of time, wherein a zero crossing may be defined as the value where the modulation drops to zero or nearly zero. In addition, or alternatively, pause may be detected by utilizing a signal strength threshold below which the audio may be characterized as being in a pause. In one embodiment, a pause may be recognized when the duration of the pause exceeds about 40 milliseconds.
[0067] It may be assumed that the longer the period of time that a pause has gone on, the longer the period of time that the pause will continue in the future. Thus, a quality check may be initiated after a pause has gone on for a predetermined period of time, such as 40 milliseconds, on the assumption that the pause is more likely to continue long enough for the quality check to be completed.
[0068] Each recognized pause may interrupt the main microprocessor, which may then query a neighboring frequency for the quality value of the neighboring frequency. The quality value may be a function of multipath, signal strength, FM frequency offset, FM modulation and/or adjacent channel noise (also termed “ultrasonic noise”).
[0069] FIG. 9 is a timing diagram depicting the muting during a neighbor frequency check triggered by the pause detection logic of DSP 24 . The muting may occur while the audio frequency (AF) Hold line is LOW, as indicated at 32 . In the example illustrated in FIG. 9 , the neighbor frequency check indicated at 32 has a duration of about 5.2 milliseconds using Tuner IF Front End IC 26 interacting with DSP 24 . The magnitude of the tuning voltage may be dependent on the neighbor frequency jump, i.e., on the frequency difference between the currently listened-to frequency and the neighbor frequency to be checked. The overall time required to perform a neighbor check may be about seven milliseconds in one embodiment. The AF Hold line may go LOW in order to mute the audio prior to the actual tuning of Tuner IF Front End IC 26 to the particular neighboring frequency, which tuning is indicated at 34 . After the commencement of tuning, as indicated at 36 , about one millisecond may be provided for settling of phase-locked loop (PLL) locking prior to actual sampling being performed during the time that the AF Sample line goes HIGH, as indicated at 38 . After the quality AF Sample check, the tuning frequency may be set back to the originally listened-to station, as indicated at 40 . After the tuning frequency is set back, time may be provided for PLL setting before the AF Hold Line goes HIGH, as indicated at 42 , to unmute the audio of the presently listened-to station.
[0070] In one embodiment, after Tuner IF Front End IC 26 has switched to the neighboring frequency, as indicated at 34 , the quality sample check is performed to gather readings of the five parameters of fieldstrength, multipath, ultrasonic noise, FM frequency offset and FM modulation. The readings may be gathered via an I2C bus which is set at 400 kbps. In order to promote fast access and avoid having to make five consecutive I2C reads from five separate and disparate memory locations in the DSP for the fieldstrength, multipath, ultrasonic noise, FM frequency offset and FM modulation parameters, DSP 24 may support calling the five registers which hold this information through one I2C read. In order to enable the single I2C read, DSP 24 may support autoincrement and the ability to map disparate memory locations via pointer access. These features may be instrumental in performing the quality sample check within the stipulated time frame and in avoiding the mute, i.e., the interruption of the audible broadcast, from being perceived by passengers of the vehicle.
[0071] When the quality sample check is performed on the neighboring frequency, the audio is muted for up to 5 . 2 milliseconds, i.e., the approximate duration of 32 in FIG. 9 , which may be imperceptible by the user.
[0072] When the audio system is in tuner mode, each quality sample check may take about seven milliseconds, which may be imperceptible to listeners so long as the quality sample checks are not performed consecutively, i.e., back to back, with no breaks in between. In one embodiment, precautions may be added in order to prevent or inhibit consecutive quality sample checks from being performed. Otherwise, consecutive performance of the checks could result in an interruption of the audible broadcast of greater than seven milliseconds, which could be perceptible to the end user listeners.
[0073] Preventing checks from occurring consecutively (e.g., back to back) is a feature of the invention that may be applied to both automated FM station list and AF switching methodology. In order to inhibit or prevent checks from being performed back to back or consecutively, which can result in the user perceiving the audio mute, a one-shot timer may be set each time a check is performed. The setting of the one-shot timer may ensure that even if there were to be a pause detect trigger immediately after a previous pause detect triggered check has been performed, the second check would be performed only if this timer has elapsed. Thus, the quality check may be an AND logic condition, meaning that a pause has occurred AND the timer is not running. If pause occurs and Timer is running, then the quality check is ignored. This consecutive check prevention one-shot timer may be calibratable.
[0074] Ensuring quality check efficiency is another feature of the invention that may be applied to both automated FM station list and AF switching methodology. The FM frequency band in the North American market has 102 frequencies ranging from 87.7 MHz to 107.9 MHz. In order to enhance efficiency in the quality sample checks, a trust timer in software may be utilized when quality check is performed on a station frequency to ensure further checks are postponed in order to achieve check efficiency. The timer value may be decremented using speed information provided by a vehicle local area network, or may be decremented by periodic tick. As soon as a station has been sampled for quality, a timer associated with that particular station may be set. As long as the timer is valid (i.e., has a non-zero value), a quality check may not be performed again on that station. Once the timer decrements to zero however, another quality check may be performed.
[0075] The trust timer may be decremented either by periodic timer tick or through speed information provided by the local area network within the car. The timer decrement via speed information may be particularly advantageous in one embodiment because if the vehicle is stationary there is no decrement of the timer. The rate of decrement may be dependent upon the speed of the vehicle.
[0076] For example, it is possible to sample station 87.5 MHz 0 (index of 87.5 MHz) and an associated trust timer for about fifteen, which time is calibratable. Subsequent checks ignore checking 87.5 MHz until its trust timer expires.
[0077] A table depicting one embodiment of a frequency learn memory used to gather apriori information is shown in FIG. 10 . The learn memory is the repository from which the subsequent logic may be derived. The learn memory may include 102 entries for the U.S. region (e.g., 87.7 MHz to 107.9 MHz with 200 kHz steps), 205 entries for the worst case FM range (e.g., 87.5 MHz to 108 MHz with 100 kHz steps), and 140 entries for the Japan region (e.g., 76 MHz to 90 MHz with 100 kHz steps).
[0078] The invention may be applied to perceptually weighted checks. To complement the pause detect logic check, the invention provides a methodology which triggers a neighborhood frequency check when the currently listened-to station has poor reception quality. More particularly, when the currently listened-to station has poor reception quality, the present invention may “sneak in” a performance check that is not easily perceived by the user. In order to enable such checks, a perceptual weighting filter based on the quality parameter is utilized. The perceptually weighted checks take advantage of the poor signal reception of the presently listened-to station to perform checks.
[0079] In order to support the checks, a one shot timer having a duration of 500 ms is used to continuously check on the current quality state of the currently tuned-to station in FM mode. If the quality state indicates noise AND a previous quality check was not performed within the one second time frame, then a quality check is initiated. This one second check guard may ensure that back to back quality checks are not performed, because such back to back checks could be perceived by the user.
[0080] The perceptual filter that may be utilized includes a three-dimensional function which inputs field strength, multipath and ultrasonic noise into a quality factor. The three parameters may be received from the DSP through autoincrement registers.
[0081] The quality information gathered may be updated into what may be termed a “frequency learn memory,” which is mapped onto on-chip RAM. One embodiment of a frequency learn memory for the North American market is shown in FIG. 11 .
[0082] To optimize on RAM, instead of storing frequency, each frequency may be presented as an index that is mapped over the range. For example, in a frequency range spanning from 87.7 MHz to 107.9 MHz, index 0 represents frequency 87.7 MHz, and index 102 represents 107.9 MHz. To otherwise store the frequency uncoded in BCD format, for example, would consume two bytes, which is not an efficient use of memory.
[0083] Quality may be derived from the three-dimensional table taking into consideration fieldstrength, multipath and ultrasonic noise. The trust timer may be a timer value that gets set once a quality check has been performed on a station.
[0084] The learn memory may be updated through the following four methods on a single tuner radio. First, when a user is tuned to an FM station and the volume knob is set to a perceivable volume level, then automatic quality checks of neighboring frequencies may be triggered whenever there is a pause in the currently tuned-to station's audio. The novelty of this idea is extended in the second through fourth options described below.
[0085] A second option for the automatic update of the FM station list is that when a user is tuned to an FM station and the volume knob is set to a perceivable volume level, then automatic quality checks of neighboring frequencies may be triggered whenever the currently tuned-to audio signal quality is poor. In one embodiment, the present invention provides a novel perceptual based table which characterizes the signal quality level. The characterization of the signal quality level may be used to trigger a 7 ms long, unperceivable quality check of a neighboring frequency.
[0086] A third option for the automatic update of the FM station list is that when a user is tuned to an FM station and the volume knob is set to total mute (or if a mute pushbutton is activated), then the neighboring frequencies are checked and updated onto the FM learn memory.
[0087] A fourth option for the automatic update of the FM station list is that when a user is sourced to a non-tuner source (e.g., CD mode, auxiliary mode), then the update of the FM station list can freely be performed without the concern that the update will be perceived by the user. Dual tuner radios may not have this limitation, as the second tuner can scan the FM memory and keep it updated.
[0088] The invention may be applied to AF switching methodology in a dual tuner radio. A dual tuner radio system 120 of the present invention is illustrated in FIG. 12 . Dual tuner radio system 120 may include a microcontroller 122 which may be used to process user input. A digital signal processor (DSP) 124 may be used to provide audio demodulation of the air-borne IF input signal. DSP 124 may also be used to provide quality information parameters to the main microcontroller 122 via a serial communication protocol such as I2C. The quality information parameters may include multipath, adjacent channel noise, FM frequency offset, FM modulation and field strength. The I2C channel may be a dedicated channel so that delays due to shared resource contentions are prevented. DSP 124 may rely on a Two-tuner IC 126 to perform the front end RF demodulation and the gain control. Two-tuner IC 126 may also output the Intermediate Frequency to DSP 124 where the Intermediate Frequency may be demodulated and processed. Two-tuner IC 126 may further provide a gain to the IF (Intermediate Frequency) signal of up to 6 dBuV prior to forwarding the signal to DSP 124 . Communication between Two-tuner IC 126 and DSP 124 , as indicated at 127 , may be via a serial communication protocol such as I2C, which may operate at 400 kbps.
[0089] An antenna system 128 may be communicatively coupled to Two Tuner IC 126 . Antenna system 128 may be in the form of a passive mast, or an active mast of phase diversity, for example.
[0090] AF sample lines 129 a - b and AF hold lines 131 a - b provide an interface between DSP 124 and Tuner IC 126 to coordinate a quick mute as described hereinbelow. In contrast to the single tuner embodiment of FIG. 8 , this dual tuner embodiment of FIG. 12 includes a separate AF Sample, AF Hold and Pause sensor for the second tuner path. Pause interrupt lines 133 a - b between DSP 124 and microcontroller 122 may be used to inform microcontroller 122 whenever a pause occurs either on the primary or secondary tuner paths.
[0091] DSP 124 may provide signal quality parameterization of demodulated tuner audio and may make it available to microcontroller 122 via a serial communication bus 130 . In one embodiment, serial communication bus 130 is in the form of a 400 kbps high speed I2C.
[0092] For dual tuner variants, second tuner may be used to conduct the PI check in an unperceived manner since the user is listening to the main tuner for the audio source. This allows the frequency learn memory to be updated with respect to quality metrics more easily than with single tuner radios, especially when the user is sourced to either AM or FM source.
[0093] Dual tuner radio variants can be of either the phase diversity type or the external switching diversity type. On dual tuner variants with phase diversity ( FIG. 13 ), a main tuner 226 is connected to an antenna 228 a, and a second tuner 227 is connected to an antenna 228 b. While main tuner 226 produces an audio signal, second tuner 227 can scan the FM spectrum in the background until the main tuned-to station experiences severe multipath. In response to the severe multipath, the background scanning may be ceased and second tuner 227 may tune to the same station that main tuner 226 is tuned to. Thus, the audio quality may be enhanced by using algorithms known as Constant Modulus Algorithm (CMA) that make use of the phase differences between the main tuner demodulated audio and the second tuner demodulated audio. For dual tuner variants with phase diversity, whenever the phase diversity is functionally enabled, the dual tuner in part operates mostly as a single tuner radio.
[0094] On dual tuner variants with external switching diversity ( FIG. 14 ), a main tuner 326 and a second tuner 327 are associated with antennas 328 a - b. While main tuner 326 produces an audio signal, second tuner 327 is constantly engaged in background scanning. The diversity in tuner variants with external switching diversity is a front end switching circuitry box 334 which chooses the better antenna signal quality. For example, as shown in FIG. 9 , box 334 determines that antenna 328 a is the stronger antenna, and thus chooses antenna 328 a, as indicated at 336 .
[0095] The frequency learn memory contains the updated information of the station frequency landscape that is currently available to the car radio. The invention provides different methods of updating the learn memory by use of single and dual tuners.
[0096] Using the quality metrics gathered in the frequency learn memory, the inventive system can employ various methods to detect the existence of an inter-modulation artifact. A first method of detecting an inter-modulation artifact includes inter-modulation detection, in which the learn memory may be checked through for all frequencies above a calibratable threshold, such as 70 dBuV for example.
[0097] In a second method of detecting an inter-modulation artifact, if the frequency signal quality is greater than or equal to 70 dbuV, and if the number of stations found equals two, then third order 2f 1 +/−f 2 and 2f 1 +/−f 2 combinations are computed. It may be checked whether the frequency is within range of the FM band, which varies based on the region. The FM band is 87.5 to 108.0 MHz for Europe (ECE) and rest of world (ROW); 76 to 90 MHz for Japan; and 87.75 to 107.9 MHz for the North American market.
[0098] In a third method of detecting an inter-modulation artifact, if the number of stations found equals three, then combinations of f 1 +/−f 2 +/−f 3 are computed and a check is made that the frequencies are within range of the respective tuner region (e.g., 87.7 to 107.9 MHz in the U.S.; 76 to 90 MHz in Japan; and 87.5 to 108.0 MHz in the Rest Of World). If the frequencies are within range of the respective tuner region, then a bit is set for these frequencies in learn memory along with a trust timer. For example, a valid count down timer may be set for fifteen minutes, or some other chosen time period. As long as the trust timer is running, the radio may be able to judge this station and skip this station frequency in Autoseek, AF switching and DAB FM link use cases.
[0099] The present invention may improve the tuner reception quality performance by avoiding third order inter-modulation artifacts in single and dual tuner radio variants in the presence of strong signal environment. The inventive method can be applied to car radios, and FM receivers in mobile devices such as cell phones, USB—FM receivers, etc.
[0100] The inventive method for detection of inter-modulation uses apriori information in improving several different applications. First, RDS AF switching behavior may be improved in single and dual tuner radios by ensuring that the radio does not switch to a tainted inter-modulation frequency.
[0101] Second, RDS preset recall performance may be improved by using the Tune by PI code to ensure that the alternative frequency picked for reception is not a frequency tainted by inter-modulation artifacts.
[0102] Third, Auto-seek seek stop performance may be improved in the FM mode to ensure that seek stop does not occur at an inter-modulation artifact.
[0103] Fourth, in Europe, DAB FM link occurs when a user is tuned to a digital DAB station. When the BER (Bit Error Rate) increases, the decoding of the MP 2 compressed audio stream becomes difficult for the DAB receiver. In such a circumstance, the radio typically falls back on the simulcast FM station frequency to produce audio. FM stations in Europe employ RDS which categorizes stations with a program ID code whereby multiple frequencies are associated with a single station. In such a case, a Tune by PI operation to trigger the DAB FM link may ensure that the final strongest alternative frequency picked for tune operation in the FM band is not an inter-modulation artifact.
[0104] Fifth, the invention may reduce effects of inter-modulation in the scenario where the user manually tunes to a station, and the radio computes the station to be a known inter-modulation tainted station frequency. For example, the radio may narrow the bandwidth of filtering in order to filter out the inter-modulation artifact. If the radio determines that it is tuned to a frequency that is itself an inter-modulation artifact, then the radio may switch to one of the “pure” frequencies that contribute to the inter-modulation artifact.
[0105] While this invention has been described as having an exemplary design, the present invention may 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. | A method of performing alternate frequency switching in a radio includes tuning the radio to a primary frequency. A candidate alternate frequency is identified. It is determined whether the candidate alternate frequency is a third order inter-modulation artifact. Tuning is switched from the primary frequency to the candidate alternate frequency only if it is determined in the determining step that the candidate alternate frequency is not a third order inter-modulation artifact. | 8 |
This is a continuation of U.S. application Ser. No. 10/146,934 filed May 17, 2002 now U.S. Pat. No. 7,037,426, which is a continuation-in-part of U.S. Ser. No. 09/889,352 filed Jul. 17, 2001, issued as U.S. Pat. No. 6,790,360 on Sep. 14, 2004, which is a National Stage entry of PCT/CA00/01359 filed Nov. 15, 2000. All of the applications listed above are incorporated herein, in their entirety, by this reference to them.
FIELD OF THE INVENTION
This invention relates to filtering membranes and particularly to modules of immersed, suction driven, ultrafiltration or microfiltration membranes used to filter water or wastewater.
BACKGROUND OF THE INVENTION
Submerged membranes are used to treat liquids containing solids to produce a filtered liquid lean in solids and an unfiltered retentate rich in solids. For example, submerged membranes are used to withdraw substantially clean water from wastewater and to withdraw potable water from well water or surface water.
Immersed membranes are generally arranged in modules which comprise the membranes and headers attached to the membranes. The modules are immersed in a tank of water containing solids. A transmembrane pressure (“TMP”) is applied across the membrane walls which causes filtered water to permeate through the membrane walls. Solids are rejected by the membranes and remain in the tank water to be biologically or chemically treated or drained from the tank.
U.S. Pat. No. 5,639,373, issued to Zenon Environmental Inc. on Jun. 17, 1997, describes one such module using hollow fibre membranes. In this module, hollow fibre membranes are held in fluid communication with a pair of vertically spaced headers. TMP is provided by suction on the lumens of the fibres through the headers. Other modules are shown in U.S. Pat. No. 5,783,083 issued to Zenon Environmental Inc. on Jul. 21, 1998, PCT Publication No. WO 98/28066 filed on Dec. 18, 1997 by Memtec America Corporation and European Patent Application No. EP 0 931 582 filed Aug. 22, 1997 by Mitsubishi Rayon Co., Ltd. As discussed in these documents, various means are provided for fixing modules together generally permanently into larger units.
SUMMARY OF THE INVENTION
It is an object of the present invention to improve on the prior art. It is another object of the present invention to provide a filtration apparatus comprising a plurality of elements, for example, elements of immersed, suction driven, hollow fibre membranes, mounted to a frame. Embodiments of the invention provide few components to interfere with the flow of tank water through the apparatus, efficient permeate pipe connections, elements that may be removed easily and without interfering with adjacent elements, elements that may be economically manufactured to a wide range of sizes, an apparatus that may be assembled with variable spacing between elements, and a distance between headers of the elements that can be altered to account for membrane shrinkage in use. The objects of the invention are met by the combinations of features, steps or both described in the claims. The following summary may not describe all necessary features of the invention which may reside in a sub-combination of the following features or in a combination of some or all of the following features and features described in other parts of this document.
In various aspects of the invention, the invention is directed at an apparatus for filtering a liquid in a tank having a plurality of elements, and a frame for holding the elements while they are immersed in the liquid. The elements have a plurality of hollow fibre membranes attached to and suspended between an upper header and a lower header. The membranes are in fluid communication with one or more permeate channels in one or more of the headers. Releasable attachments between the headers and the frame allow the frame to releasably hold the elements by their headers. While the frame is holding the elements, the elements themselves do not have any means for holding the headers in position relative to each other. For example, if the frame were removed, the headers would be free to move out of position relative to each other. As a result, the size and configuration of the frame determines the positions of the upper and lower headers of each element relative to each other. When out of the frame, the elements may be inserted into a separate carrying frame, if desired, for transport or handling.
An assembled filtration apparatus, which may be called a cassette, has a plurality of elements held such that the membranes are generally vertical when immersed in the liquid in the tank. The headers may be elongated in shape and held in a generally horizontal orientation when the membranes are immersed in the tank. The frame holds the elements so as to provide a spacing between adjacent elements and allows tank water to rise vertically through the frame and past the elements.
To assemble a filtration apparatus, the upper headers are slid into the frame, for example, through track and slider mechanism that may support the element whenever about one quarter of the length of the upper header is inserted into the frame. The lower header may similarly slide into the frame, for example through another track and slider mechanism. Or, while the element is supported by the upper header, the lower header may be swung into position to attach to releasable supports which engage with the ends of the lower header.
The frame holds or restrains the elements in place, but the restraint provided by the frame may be released for a selected element individually. The selected element may be removed by reversing the steps for assembly without disassembling the remainder of the module. Connections between the permeate channels and one or more permeate collection tubes attached to the frame are releasable and resealable connections which are made or broken automatically by the movements involved in inserting or removing an element into or out of the frame.
The frame may have cross bars located on uprights, the cross bars holding the elements. The vertical location of the cross bars may be changed from time to time to maintain the membranes in a slightly slackened condition although their length may decrease in use.
Aerators are mounted generally below the elements and supply scouring bubbles to the cassette and circulate tank water. The elements may be narrow, each element being a rectangular skein of hollow fibres having an effective thickness of between 4 and 8 rows of hollow fibres. The headers, which may be extruded, may be thin to not greatly increase the width of the element. The attachments between the frame and the elements are positioned to provide horizontal spaces between adjacent elements, preferably at least one third of the width of the headers measured in the direction of the horizontal spacing, to promote penetration of the bubbles and tank water into the elements.
Elements may be placed back to back in pairs separated by permeate pipes. The connections between the permeate pipes and the elements release when an element is pulled out of the cassette and reseal when the element is replaced in the cassette. Thus a single element can be removed for maintenance without disconnecting other parts of the permeate pipe network. A large permeate collector may be connected to a small group of elements by a short local permeate pipe with a valve that permits the small group of elements to be isolated. Thus, while waiting for repair, permeation can continue with the remaining elements. The large permeate collector may be located above the water surface and connect to an even larger collector which may be located on the edges of a tank.
The headers may be made of an extrusion which may be cut to any desired length and capped with caps. The horizontal distance between the cross bars of the frame can be altered by changing the dimensions of the frame or the location of the cross bars relative to the frame. Longer or shorter cross bars can be used which hold fewer or more elements. The vertical distance between cross bars can be altered by changing the dimensions of the frame or the location of the cross bars relative to the frame. Accordingly, a cassette may be produced in a variety of sizes by altering the length of cut of one or more of the header extrusion, the cross bars or the frame members.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will now be described with reference to the following figures.
FIG. 1 is a somewhat schematic front elevation of a filtering element.
FIG. 2 is a somewhat schematic side elevation of the filtering element of FIG. 1 .
FIG. 3 is an isometric view of a header of an element of a first embodiment.
FIG. 4 is an elevation of the end of 4 adjacent headers of FIG. 3 .
FIG. 5 is an isometric view of a frame for a cassette with headers attached.
FIG. 6 is a close up of the top of FIG. 5 .
FIG. 7 is a diagrammatic drawing of part of two elements placed back to back and connected to a permeate pipe.
FIG. 8A is a perspective view of a header and releasable attachment of a second embodiment.
FIG. 8B is a side view of the header of FIG. 8A .
FIGS. 9 and 10 are assembled and exploded views of a component of the releasable attachment of FIG. 8 .
FIG. 11 is a perspective view of parts of a frame and releasable attachments of the second embodiment.
FIGS. 12 , 13 and 14 are perspective, front and side views of a frame and parts of releasable attachments of the second embodiment.
FIG. 15A is a perspective view of an element of a third embodiment.
FIG. 15B is a close up view of part of FIG. 15A .
FIGS. 16A , 16 B and 16 C are schematic views of elements and permeate connections of a third embodiment.
FIG. 17 is a perspective view of a header and parts of a releasable attachment of the third embodiment.
FIGS. 18A and 18B are side views of the releasable attachment between a lower header and frame of the third embodiment.
DETAILED DESCRIPTION OF THE INVENTION
A First Embodiment
The following paragraphs describe a first embodiment that is shown in FIGS. 1 to 7 . Although the description below may at times refer to specific figures, some components discussed may be shown only in others of FIGS. 1 to 7 .
FIGS. 1 and 2 show simplified front and side elevations respectively of a filtering element 10 . The element 10 has a plurality of hollow fibre membranes 12 in the form of a rectangular skein 14 suspended between an upper header 16 and a lower header 18 . The rectangular skeins 14 may be between four and eight layers of membranes 12 deep (five layers being shown in FIG. 2 ), optionally up to 12 layers deep, and are in the range of several tens of membranes 12 wide. The element 10 itself does not include any permanently attached means for holding the headers 16 , 18 in position relative to each other but the element 10 may be connected to a carrying frame if required for transport or handling. The lack of means for holding the headers 16 , 18 in position relative to each other improves the flow of tank water about the element 10 and avoids a possible source of damage to the membranes 12 .
The membranes 12 typically have an outside diameter between 0.4 mm and 4.0 mm. The length of the membranes 12 is chosen to maximize flux for a given cost according to relationships known in the art and is typically between 400 mm and 1,800 mm. The membranes 12 have an average pore size in the microfiltration or ultrafiltration range, preferably between 0.003 microns and 10 microns and more preferably between 0.02 microns and 1 micron.
The upper header 16 has a permeate channel 20 in fluid communication with the lumens of the membranes 12 . The membranes 12 in FIGS. 1 and 2 are sealed in the lower header 18 , but the lower header 18 may also have a permeate channel in fluid communication with the lumens of the membranes 12 to permit permeation from both ends of the membranes 12 . The membranes 12 are potted into the upper header 16 (and any other permeating header) such that the membranes 12 are all closely spaced apart from each other. Potting resin completely surrounds the outsides of the end of each membrane 12 to provide a watertight seal so that water can only enter the permeate channel after first flowing though the membranes 12 . Suitable potting resins include polyurethane, epoxy, rubberized epoxy and silicone resin. One or more resins may also be used in combination to meet objectives of strength and providing a soft interface with the membranes 12 and avoiding cutting edges.
A potting method like that described in U.S. Pat. No. 5,639,373, which is incorporated herein by this reference, may be used to pot layers of membranes 12 . Other potting methods known in the art, include methods that produce non-layered or random arrangements of the membranes, may also be used. In particular, the methods described in Canadian Patent Application No. 2,308,234, filed May 5, 2000 by Zenon Environmental Inc., and in U.S. application Ser. No. 09/847,338, filed on May 3, 2001 by Rabie et al., both of which are incorporated herein by this reference, may be used. The thickness of the assembled mass of membranes 12 may be between 18 and 40 mm. Headers 16 , 18 to accommodate such masses of membranes may be 40 to 50 mm wide, typically 40 mm. The potting densities may be between 10% and 40%. For example, an element 10 may use membranes 12 as used in commercially available ZW 500 (TM) modules made by Zenon Environmental Inc. which have an outside diameter of about 2 mm, an un-potted length (meaning the unsupported length of membrane 12 between the upper header 16 and lower header 18 ) of 1,600 to 1,900 mm, and a pore size of approximately 0.1 microns.
Referring to FIG. 3 , the upper header 16 is shown. The lower header 18 is the same would be mounted in an inverted position. The upper header 16 includes a body 22 preferably extruded from a suitable plastic such as PVC or ABS. The extrusion can be cut to a wide range of sizes as desired. A back cap 24 is attached to the body 22 by gluing or welding. The body 22 includes a key 26 running the length of the top of the upper header 16 . The back cap 24 is shaped to extend the key 26 . The key 26 fits into slots in cross bars 30 of which only short sections are shown. The back cap 24 has an upper wing 32 and a lower wing 34 . The back cap 24 and the body 22 each have an upper channel 36 and a lower channel 38 . A front cap is attached to the front of the body 22 but has been omitted from FIG. 3 to show the cross-section of the body 22 . The front cap need not have any wings 32 , 34 but it does have channels 36 , 38 ,
Referring to FIG. 4 , four upper headers 16 are attached to a section of cross bar 30 spaced to leave about 20 to 25 mm between adjacent upper header 16 . The lower headers 18 are similarly attached to another crossbar 30 but in an inverted position. The cross bar 30 can be cut to any desired length. To avoid the need to cut slots 28 into a long cross bar, the one piece cross bar 30 shown can be replaced with a standard extruded section, such as an inverted “C” channel, which supports any suitable hanger containing a slot 28 . In that case, the standard extrusion is cut to a desired length and an appropriate number of hangers are attached or slid into it which allows the number of elements 10 to be easily varied.
The upper headers 16 and their associated upper wings 32 , lower wings 34 , upper channels 36 and lower channels 38 are all designated a, b, c, d to indicate which of those parts is associated with which upper header 16 . As shown, the upper wing 32 of a first upper header 16 engages the upper channel 36 of an adjacent upper header 16 and the lower wing 34 of the first upper header 16 engages the lower channel 38 of an adjacent upper header 16 on the other side. But, the upper wings 32 and lower wings 34 do not interfere with each other in the direction of the length of the upper headers 16 . Accordingly, each upper header 16 can be moved into or out of its position in a direction parallel to the upper header 16 . Further, although the cross bar 30 provides support at only one point, a moving upper header 16 is supported and vertically positioned by its adjacent upper headers 16 aong its travel. This makes it much easier to insert or withdraw an element 10 despite the lack of (a) means within the element 10 itself for maintaining separation between the headers 16 , 18 or (b) continuous frame channels paralleling the length of each header 16 , 18 which would add many parts, add to the overall cost and manufacturing time, as well as interfere with bubbles and tank water moving past the headers 16 , 18 . A releasable catch can be incorporated into the slot 28 and key 26 structure, typically at the front only, to provide a releasable restraint in the direction of the headers 16 , 18 .
Referring to FIGS. 5 and 6 , a cassette 50 includes a frame 40 for holding several elements 10 . The frame 40 includes top and bottom, front and back cross bars 30 , uprights 42 and struts 44 as shown. Three elements 10 (with membranes 12 removed for clarity) are shown being withdrawn from the frame 40 . Extra blank (ie. unpotted) headers 48 are optionally included between the uprights 42 to provide support for the wings 32 , 34 of the first element 10 on each side. An element 10 may be completely withdrawn and then supported by hand or a single element carrying frame (not shown) may be placed against the frame 40 . The element 10 is then slid into the carrying frame which may allow the element 10 to be more easily worked with.
The length of the uprights 42 is chosen as appropriate for any desired length of membranes 12 . The vertical distance between cross bars 30 is chosen so that the membranes 12 will be slightly slacked, their free length being, for example, 0.1% to 2% more than the distance between proximal faces of the headers 16 , 18 . Particularly in wastewater applications where the tank water will be warm, ie. 30-50 C, the membranes 12 may shrink within the first few weeks or months of operation. To account for this shrinkage, the uprights 42 may be provided with a series of mounting holes 46 which allow at least one set of the upper or lower cross bars 30 to be moved to maintain the membranes 12 in a slightly slackened position. Although not shown, a suitable aerator (designs are known in the art) may be mounted to the frame 40 or placed on a tank floor below the frame 40 to provide bubbles from below the cassette 50 . The aerator is designed and positioned to encourage bubbles and tank water to flow upwards through the frame 40 and past the elements 10 , through the spaces between adjacent elements 10 and between the membranes 12 within the elements 10 .
To connect the headers 16 , 18 to permeate pipes, the back of any permeating headers 16 , 18 are fitted with header permeate connections 52 that can be released and resealed to a permeate pipe located behind the headers 16 , 18 and permit movement of the element 10 parallel to the headers 16 , 18 . For example, FIGS. 5 and 6 show commercially available clip on adapters sold under the trade mark UNI-SPRAY. These connectors 52 , however, require a clip to be released at the back of the element 10 which is difficult to do if the elements 10 are placed back to back to share common permeate pipes.
Referring to FIG. 7 , pairs of cassettes 50 (partially shown, frames 40 omitted, for example) are placed back to back with a local permeate pipe 60 in between them. The frames 40 (not shown) of the two cassettes 50 are tied together to maintain a fixed distance between them. The upper headers 16 (and lower headers 18 if they are permeating) include male fittings 54 which releasably form a seal with a female fitting 56 attached to the local permeate pipe 60 . The seal is made by means of O-rings 58 fitted into O-ring grooves 66 in the male fittings 54 . The male fittings 54 are thus connected to a local permeate pipe 60 which may service a small number of elements 10 , ie. 2-6 elements 10 . The local permeate pipe 60 has an isolation valve 62 , for example a ball valve located above the water line, which permits the small group of elements 10 to be isolated from the rest of the cassette 50 . The local permeate pipes 60 connect into a larger permeate collector 64 which may be located at the level of even larger collector which may be located at the edge of a tank. Thus, the necessary connections may be made simply and without expensive flexible pipes. If the bottom headers 18 are also permeating, appropriate male fittings 54 are attached to the bottom headers 18 at the level of female fittings 56 on or in communication with a local permeate pipe extension 68 which may be an extension of the local permeate pipe 60 . If the bottom headers 18 are permeating headers, then the top headers may not be.
A Second Embodiment
The following paragraphs describe a second embodiment, parts of which are shown in FIGS. 8 to 14 . Although the description below may at times refer to specific figures, some components discussed may be shown only in others of FIGS. 8 to 14 or in figures discussed with other embodiments. The second embodiment is similar to the first embodiment in many respects. Aspects of the second embodiment that do not differ substantially from the first embodiment may not be described in the following paragraphs which will concentrate on the features of the second embodiment which differ from the first.
A second lower header 118 is shown in FIGS. 8A and 8B . A second upper header 116 (not shown in this figure) is similar, but mounted in an inverted position. The second lower header 118 has a second key 126 on its lower surface that may be continuous like that of the second header 18 . Optionally, the second key 126 may be segmented, for example as shown in FIG. 8B , which helps prevent the second key 126 from sticking in the second slot 128 , which will be described below.
The second lower header 118 does not have an upper channel 36 or a lower channel 38 . A second back cap 124 of the second lower header 188 also does not have an upper wing 32 or a lower wing 34 , but rather is of a similar section as the second body 122 of the second lower header. A second front cap 125 is fitted to the front of the second body and has a pull tool fitting 180 adapted to allow a tool to pull on the second lower header 118 for removal.
FIG. 8A also shows a track piece 182 located below the second lower header 118 . A similar track piece 182 would be located above the second upper header 116 . The track piece 182 provides part of a continuous second slot 128 that the second keys 126 may slide into and be supported by. The track piece 182 is supported at both ends by the cross bars 30 . For example, in the embodiment shown, one end of the track piece 182 fits over and is supported by an abutment 184 attached to the side of a permeate pipe stub 186 resting on a cross bar 30 . The permeate pipe stub 186 is sealed at its lower end and ready to be connected to a local permeate pipe extension 68 (not shown in FIG. 8A , refer to FIG. 7 ) at its upper end. The permeate pipe stub 186 also has female fittings 56 in fluid communication with the inside of the permeate pipe stub 186 . The female fittings 56 are located and oriented so that when the second lower header 118 is fully inserted in the second slot 128 , a male fitting 54 (not visible) is sealingly connected to the female fitting 56 . The other end of the track piece 182 in the embodiment shown is supported by a locking clip 188 which both supports the track piece 182 relative to the cross bar 30 , but also completes the second slot 128 and releasably locks the second lower header 118 in position when the second lower header 118 is fully inserted in the second slot 128 . The locking clip 188 is held in place by fitting into a cross bar channel 192 and is located along the length of the cross bar 30 by interaction with a positioning hole 190 . The description above also applies, but with inverted orientation, for the second upper headers 116 .
FIGS. 9 and 10 show the locking clip 188 in greater detail. A locking clip abutment 194 is sized and shaped to fit into and support the track piece 182 . A peg 196 fits into a peg slot 198 to provide a means for locating the locking clip 188 over a positioning hole 190 . A catch 200 fits over the body of the locking clip 188 and, in an unbent position, fills a part of the second slot 128 . However, the catch 200 has tapered faces so that the catch 200 can move out of the second slot when a second key 126 is slid into the second slot 128 . After the end of a second key 126 , or series of discontinuous second keys 126 passes the catch 200 , they are prevented from moving back out of the second slot 126 . However, a release hole 202 also provides access to the tapered faces of the catch 200 . By inserting a rod into the release hole 202 , the catch 200 can be held open to allow a second key 126 to be pulled back out of the second slot 128 . The locking clip 188 also has a foot 204 sized to engage with the cross bar channel 192 .
FIG. 11 shows how the bottom part of a frame 40 ready to receive second elements 110 . As shown, a pair of struts 44 are attached to a central cross bar 30 a and two end cross bars 30 b , only one visible. Four brackets 206 are provided to attach to uprights 42 . The central cross bar 30 a supports a number of permeate pipe stubs 186 which in turn have abutments 184 holding track pieces 182 . The end cross bars 30 b support locking clips 188 which support the other ends of the track pieces 182 . If the second lower headers 118 were not permeating headers, then the central cross bar 30 a would also be used to support locking clips 188 .
FIGS. 12 to 14 show a more fully assembled frame 40 forming part of a second cassette 150 . A second assembly like that shown in FIG. 11 is inverted and placed over the assembly of FIG. 11 . Uprights 42 hold the two assemblies together. The connection between the uprights 42 and one or both of the assemblies may be made though slots 208 which allow the distance between the two assemblies to be adjusted to fit the second elements 110 . The distance between the two assemblies may also be adjusted after the membranes 12 have been used, for example, to account for shrinking. The upper track pieces 182 are held at the central cross bar 30 a by flow through permeate stubs 210 which connect the local permeate pipe extensions 68 to local permeate pipes 60 which are in turn connected to a permeate collector 64 mounted to upper mounting tabs 212 at the top of the frame. Lower mounting tabs 214 at the bottom of the frame 40 may be used to mount an aerator grid below the second cassette 150 . Only one of various components, such as second elements 110 , local permeate pipe extensions 68 , local permeate pipes 60 and isolation valves 62 , are shown for clarity, but these components would be repeated across the second cassette 150 . Also, although the second cassette 150 is shown as configured to collect permeate from second upper headers 116 and second lower headers 118 , it may be adapted for use with permeating second upper headers 116 only by replacing the permeate pipe stubs 186 shown on the lower central cross bar 30 a with locking clips 188 and replacing the flow through permeate stubs 210 shown at the upper central cross bar 30 b with permeate pipe stubs 186 . For use with permeating second lower headers 118 only, the female fittings 56 of the flow through permeate stubs 210 are plugged up or altered flow through permeate stubs not having female fittings 56 are provided.
A Third Embodiment
The following paragraphs describe a third embodiment, parts of which are shown in FIGS. 15 to 18 , or in figures discussed with other embodiments. The third embodiment is similar to the first and second embodiments in many respects. Aspects of the third embodiment that do not differ substantially from the first or second embodiment may not be described in the following paragraphs which will concentrate on the features of the third embodiment which differ from the first or second.
FIGS. 15A and 15B show a third element 310 . The third element 310 has a third lower header 318 and a third upper header 316 which are similar to the second lower header 118 and second upper header 116 . However, the third headers 316 , 318 differ, for example, in having third keys 326 , third back caps 324 and third front caps 325 unlike related components of the second headers 116 , 118 . The third element 310 shown has two permeating third headers 316 , 318 , but like previous elements may be made with either the third lower header 318 not a permeating header or the third upper header 316 not a permeating header.
Referring to FIGS. 15 B and 16 A,B,C, the third headers 316 , 318 have third back end caps 324 with male fittings 54 that are offset from the center of the third back end caps 324 . Third back end caps 324 A (shown schematically in FIGS. 16 A,B,C as having truncated tops) have a male fittings 54 offset to one side of the center while third back end caps 324 B (shown schematically in FIG. 16 A,B,C as having rounded tops) have a male fitting 54 offset to the other side of the center. By placing one of third back end cap 324 A and one third back end cap 324 B on the third headers 316 , 318 , third elements 310 I and 310 II can be made have male fittings 54 offset to opposite sides. If both of the third headers 316 , 318 are permeating, then separate third elements 310 I and 310 II need not be made, as one will be an inverted version of the other. In conjunction with third permeate pipe stubs 386 having female fittings 56 on either side, a variable horizontal spacing between third elements 310 I and 310 II can be achieved with a single design of third permeate pipe stub 386 and without needing a third permeate pipe stub 386 for each third element 310 . In particular, as shown in FIGS. 16A and 16C , swapping third element 310 I for third element 310 II (or turning each third element 310 I or 310 II over if both third headers 316 , 318 are permeating) significantly alters the space between third elements 310 I and 310 II. By using third permeate pipe stubs 386 that can be mounted at various positions along a cross bar 30 , two different spacings of all of the third elements 310 of a third cassette 350 can be achieved without requiring a separate local permeate pipe 60 and local permeate pipe extension 68 for each third element 310 and with only one small component, the third back caps 324 , manufactured in two versions. The ability to have variable spacing is useful, for example, because a wider spacing can be chosen for wastewater applications and a narrower spacing chosen for drinking water filtration. As shown in FIG. 16B , an intermediate spacing may also be achieved by using a pair of third elements 310 II. The same intermediate spacing may also be achieved by using a pair of third elements 310 I.
The comments made in the paragraph above regarding the third permeate pipe stubs 386 similarly apply to third flow through permeate stubs 310 . The third permeate stubs 310 also have a pair of mounting pins 220 on each side to support the end of the third track piece 382 (to be described below) at either spacing. Similar pairs of mounting pins 220 may also be provided on the third permeate pipe stubs 386 if they will also be used to support the ends of third track pieces 383 , although this is optional as will be described further below.
FIGS. 15B and 17 show a third key 326 that which has a key ridge 224 . Although FIGS. 15B and 17 show only a third upper header 316 , the third lower header 318 is the same, but is mounted in an inverted orientation. Similarly, other components of FIG. 17 may all be used in inverted orientation at the bottom of a third cassette 350 . The key ridge 324 provides a line of contact between the distal surface of the third key 326 and the third track piece 382 . Similarly, the edges of the third track piece 382 curl inwards to provide a line of contact with the proximal surfaces of the third key 326 . These lines of contact are less prone to fouling than planes of contact.
FIG. 17 also shows the connection between one end of the third track pieces 382 and a cross bar 30 . The connection between the other end of the third track piece 382 and the third permeate pipe stubs 386 , or third flow through permeate stubs 310 , was discussed above. The end shown in FIGS. 15B and 17 is supported on a pin (not visible) one a track mounting plate 226 mounted on a cross bar 30 . The track mounting plate 226 also supports a third lock 388 that assists in keeping the third track piece 382 in position. The third lock 388 also mates with a twist knob 228 to allow the third upper header 316 to be releasably secured when it has been fully inserted into the third slot 328 .
As an alternative to using an inverted version of the components shown in FIG. 17 to releasably attach the third lower header 318 , FIGS. 18A and 18B show how the third lower header 318 may be Releasably attached to the frame 40 without using a third track piece 382 . Referring to FIG. 18A , the third top header 316 (not shown) is partially inserted, for example between about one half to three quarters of the way, into the third track piece 382 (not shown). At this point, the third lower header 318 hangs from the membranes 12 . The third lower header 318 is then pushed into its final position which is shown in FIG. 18B . Because the third upper header 316 was only partially inserted, the third lower header 318 arcs upwards slightly. Through trial and error or measurement and calculation, a position of the third upper header 316 can be determined at which the upward movement of the third lower header 318 , despite the excess length of the membranes 12 required to produce slackened membranes 12 when the third element 310 is fully installed, allows the male fitting 54 to meet the female fitting 56 and allows the twist knob 228 to meet and be releasably connected to the third lock 388 . The third upper header 318 is then fully inserted which restores the slack in the membranes 12 . The twist knob 228 of the third upper header 316 is then engaged with the third lock 388 of the upper part of the frame 40 .
The embodiments described above are examples of the invention only. Modifications and other embodiments within the scope of the invention will be apparent to those skilled in the art. The scope of the invention is defined by the following claims. | An apparatus for filtering a liquid in a tank has a plurality of elements and a frame for holding the elements while they are immersed in the liquid. The elements have a plurality of hollow fibre membranes attached to and suspended between an upper header and a lower header. The membranes are in fluid communication with one or more permeate channels in one or more of the headers. Releasable attachments between the headers and the frame allow the frame to releasably hold the elements by their headers. The size and configuration of the frame determines the positions of the upper and lower headers of each element relative to each other. Connections between the permeate channels and one or more permeate collection tubes attached to the frame are releasable and resealable connections which are made or broken automatically by the movements involved in inserting or removing an element into or out of the frame. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to electronic circuits and semiconductor devices that will receive light and convert the light to an electronic signal representing the amplitude of the light commonly referred to as photo-sensors or pixel sensors. More particularly this invention relates to methods and apparatus for testing light sensing devices, circuits, and blocks. This invention further identifies the use of such DFT methods and apparatus for testing of functionality and manufacturing process values to assure the operation of photosensors or pixel sensors in providing reliable and accurate electronic shuttering of captured light information as an array of pixels. This invention especially relates to methods and apparatus for testing of circuits and blocks known as active pixel sensors (APS).
2. Description of Related Art
Imaging circuits typically include a two dimensional array of photo-sensors. Each photo-sensor comprises one picture element (pixel) of the image. Light energy emitted or reflected from an object impinges upon the array of photo-sensors The light energy is converted by the photo-sensors to an electrical signal. Imaging circuitry scans the individual photo-sensors to readout the electrical signals. The electrical signals of the image is processed by external circuitry for subsequent display.
Modern metal oxide semiconductor (MOS) design and processing techniques have been developed that provide for the capture of light as charge and the transporting of that charge within APS and other structures so as to be accomplished with almost perfect efficiency and accuracy.
U.S. Pat. No. 5,841,126 (Fossum, et. al.) describes a CMOS active pixel sensor (APS) type imaging system on a chip. The imaging system consists of an APS and a controller on a single substrate. The controller provides specialized support electronics that are integrate onto the same substrate as the APS array. The controller includes integration, timing, control electronics, signal chain electronics, A/D Conversion, and other important control systems.
U.S. Pat. No. 5,900,623 (Tsang, et. al.) describes an active pixel sensor implemented with CMOS technology that employs an array of photocells. Each cell includes a photodiode to sense illumination and a separate storage node with a stored charge that is discharged during an integration period by the photocurrent generated by the photodiode. Each photocell includes a switching network that couples the photocurrent to the storage node only during the integration period while ensuring that a relatively constant voltage is maintained across the photodiode during integration and non-integration periods.
While the prior art patents describe the system, circuitry, functioning, and timing of pixel circuits and APS. None of the patents include any aspects of testing apparatus and methods for testing functionality, evaluating performance or determining capacitance of an APS.
FIG. 1 shows a typical CMOS Active Pixel Sensor (APS) of the prior art, using a photo-diode as a photo-conversion device for example. The drain terminals of the transistors M 1 and M 2 are connected to the power supply voltage distribution line, V DD . The source of the transistor M 2 is connected to the anode of the photo-diode D F . The cathode of the photo-diode is connected to the ground reference point. The capacitance C FD is the inherent capacitance of the photo-diode D F .
The gate of the transistor M 2 is connected to a reset terminal to receive the reset signal V rst . The sensor readout node FD, that is the anode of the photo-diode D F , is first reset to a high voltage level (V DD ) by changing the reset signal V rst from a low voltage level (0) to a high voltage level (V DD ) to charge the capacitance C FD . At the completion of charging the capacitance C FD , the reset signal V rst is changed from the high voltage level (V DD ) to the low voltage level. Since light is shown on the photo-diode D F , photo-generated electrons are collected at node FD and the voltage at the node FD decreases in the process. At the end of the exposure duration the voltage at node FD is measured, thus completing one photo-sensing cycle. The photo-sensing cycle is completed by deactivating the transistor M 3 by changing the row select signal from the high voltage level (V DD ) to the low voltage level (0).
The gate of the transistor M 1 is connected to the node FD and the source of the transistor M 1 is connected to the drain of the transistor M 3 . The transistor M 1 acts as a source follower such that the voltage present at the source of the transistor M 1 “follows” directly the voltage present at the gate of the transistor M 1 and is one transistor threshold voltage V T below the voltage present at the gate of the transistor M 1 .
The gate of the transistor M 3 is connected to the row select line to receive the row select signal V row . The source of the transistor M 3 is connected to the column bus ColBus. The column bus interconnects all the APS's present on a column of an array of APS's. When the row select signal changes from a low voltage level (0V) to a high level (V DD ), the transistor M 3 turns-on and the voltage present at the source of the transistor M 1 is transferred to the output of the APS to couple the voltage that is proportional to the intensity of the light L. The output signal V out — pixel of the APS is coupled to the column bus ColBus for further conditioning and readout.
An APS signal conditioning and readout circuit as shown in FIG. 2 and described in Fossum, et. al. is connected to the column bus ColBus of each column of APS's of an array of APS's. The APS signal and readout circuit employs correlated double sampling (CDS) to determine the level of the light L impinged upon the photodiode D f . Correlated double sampling (CDS) is achieved by sampling both a reset reference level and a signal level. The difference between the signal level and the reset reference level represents the net signal induced by level of the light L illuminating the photodiode D F . The resulting voltage of the node FD is read out through the transistors M 1 and M 3 of the APS pixel circuit of FIG. 1 onto the column bus ColBus. The voltage V out — pixel on the column bus ColBus is sampled onto a first holding capacitor C 1 by an activation pulse SHR to the gate of the transistor M 6 . This initial charge is used as the baseline. After raising the reset signal V rst , the signal charges within the APS pixel circuit due to the impinging of photoelectrons and the capacitance C FD . The resulting voltage V out — pixel is also transferred onto the column bus ColBus and sampled onto a second holding capacitor C 2 by an activation pulse SHS to the gate of the transistor M 5 . The difference between the voltages on the first capacitor C 1 and the second capacitor C 2 is therefore indicative of the number of photoelectrons of the light L that were allowed to enter the photodiode D f .
A key element in the calculation of the conversion gain in a CMOS APS imager pixel is the measurement of the capacitance C FD at the pixel readout node, FD.
In the prior art, a conventional APS test scheme used to measure the capacitance is shown in FIG. 3 . To summarize how such an APS test approach is used, a photo-diode pixel of FIG. 1 is used as an example.
The structure of FIG. 1 is modified such that the drain connections of the transistors M 1 and M 2 are separately connected. The drain of M 1 is now connected to the supply line, V DD 1 , while the drain of M 2 is connected to another supply line, V DD 2 .
The voltage source VS 1 driving the supply line V DD 1 is set to a voltage level of the power supply voltage source V DD . A second voltage source connected to the V DD 2 line is also set to the same value, the power supply voltage source V DD . Bright light is shown on the pixel so that it is saturated. The reset signal V rst is pulsed periodically and the resulting average current from the voltage source is measured. The equation relating the measured average current I and the capacitance C FD on the node FD of the photo-diode D F is calculated by the formula:
I=dQ/dt=Q FD *dV/dt Eq. 1
where:
dt is the period of the reset signal V rst
dV is the voltage difference between reset level and saturation level.
The capacitance is therefore: C FD = I V t Eq . 2
Although the electrical design of the APS pixel test approach shown in FIG. 2 is similar to the one shown in FIG. 1, the physical layout of the two pixels are quite different. In a normal pixel design, in order to increase the density of the pixels per unit area of the APS's and to reduce the complexity of signal routing, the drains of M 1 and M 2 are connected together to the same supply, V DD , through a single metal line.
However in the APS cell test approach of the prior art, since the drain connections of transistors M 1 and M 2 in FIG. 3 need to be separated in order to facilitate the above test measurement, two metal lines are needed to route the two drain connections. As a result, the pixel design is less area efficient than a design that includes no special test circuitry.
In the design approach for imaging products using arrays of APS cells, in actual application, it is preferred that the more efficient pixel in FIG. 1 is used. In order to measure the conversion gain of the pixel design implemented using a particular semiconductor manufacturing process, an additional row of the pixel cells implemented using an approach such as shown in FIG. 3 needs to be added to the normal APS pixel array.
In addition, in a conventional APS array embodiment, the additional row of testable APS pixels cannot be covered up by light shielding material to form part of the “dark pixels” normally placed around the active pixels since they must operate under bright light for the measurement
SUMMARY OF THE INVENTION
It is an objective of this invention is to provide an apparatus for testing an active pixel sensor to ensure that a signal proportional to the quantity of light energy impinging on the active pixel sensor is reliably and accurately captured and made available for further on processing the rest of the APS system circuitry.
It is another objective of this invention is to provide a method and apparatus for determining the capacitance of a photo-conversion device of the active pixel sensor.
Further, it is an object of this invention to provide a method and apparatus for determining that an active pixel sensor is functioning correctly.
Still further, is it is an object of this invention to provide a method and apparatus for determining the performance of an active pixel sensor. Where the performance of the active pixel sensor is a measure of linearity of the active pixel sensor and a connected chain of circuitry that process the signal converted by the photo-conversion device of the active pixel sensor.
To accomplish these and other objectives, an apparatus for testing functionality, evaluating performance and measuring capacitance of a photo-conversion device of at least one active pixel sensor of an array of active pixel sensors has a test voltage selection circuit. The test voltage selection circuit selectively applies any of a plurality of voltage levels that vary incrementally from a first voltage level to a second voltage level to a reference distribution node of the active pixel sensors. The apparatus further has a timing control circuit. The timing control circuit is connected to the test voltage circuit and to the array of active pixel sensors, and to a signal conditioning and readout circuit to provide signals to select timings to select application of the first voltage level and the second voltage level to the reference distribution node of the active pixel sensors, signals at appropriate timings to condition the active pixel sensors in preparation for sensing light impinging upon the array of active pixel sensors, and providing signals for timing the signal conditioning and readout circuit to sense a signal from each active pixel sensor indicating a magnitude of light impinging upon the array of active pixel sensors.
A first embodiment of the test voltage selection circuit includes a first switch. The first switch has a first terminal connected to a first voltage source that provides the first voltage level, a second terminal connected to the reference distribution node of at least one active pixel sensor on a row of active pixel sensors, and a control terminal connected to the controlling circuit to selectively connect and disconnect the first terminal with the second terminal. The test voltage selection circuit has a second switch. The second switch has a first terminal connected to a second voltage source that provides the second voltage level, a second terminal connected to the reference distribution node of at least one active pixel sensor on the row of active pixel sensors in the array of active pixel sensors, and a control terminal connected to the controlling circuit to selectively connect and disconnect the first terminal with the second terminal. The test voltage selection circuit has a current measuring device connected so as to measure a current flowing from the first voltage source.
The timing control circuit enables measurement of the capacitance of the photo-conversion device within one active pixel sensor by selecting the active pixel sensor at a first time. At a second time, the second voltage level is placed at the reference distribution node of the active pixel sensor and simultaneously, at the second time, the second voltage level is coupled to the photo-conversion device. Subsequent to applying the second voltage level to the photo-conversion device, the first voltage level is applied to the reference distribution node at a third time. Simultaneously, at the third time, the first voltage level is coupled to the photo-conversion device. The current flowing to the photo-conversion device to charge the capacitance of the photo-conversion device from the first voltage level to the second voltage level is measured. The capacitance of the photo-conversion device is determined by the formula: C FD = I V t
where
C FD is the total capacitance of the photo-conversion devices and the parasitic capacitance of the test voltage select circuit,
I is the current flowing from the first voltage source,
dv is the difference between the first voltage level and the second voltage level, and
dt is a charging time for the capacitance;
The timing control circuit enables testing functionality of a row of the active pixel sensors within the array of active pixel sensors and the chain of circuitry connecting the selected row of active pixel sensors selecting the row of active pixel sensors at a first time. At a second time, one of the plurality of voltage levels is placed on each reference distribution node of each active pixel sensor. The magnitude of the voltage level placed on each reference distribution node is indicative of a position on the row of active pixel sensors of each active pixel sensor. Simultaneously, at the second time, the voltage level of the plurality of voltage levels is coupled to the photo-conversion device to charge the capacitance of the photo-conversion device to the voltage level. The voltage level of the capacitance of each active pixel sensor on the selected row of active pixel sensors sampled and held the within the signal conditioning and readout circuit at a third time. The first voltage level is placed at the reference distribution node of each active pixel sensor on the row of active pixel sensors at a fourth time. Simultaneously, at the fourth time, the first voltage level is coupled to the capacitance of the photo-conversion device of each active pixel sensor of the row of active pixel sensors. At a fifth time, the first voltage level sampled and held on the capacitance of the photo-conversion device of each active pixel sensor on the selected row of active pixel sensors within the signal conditioning and readout circuit. The sampled and held voltage level of the plurality of voltage levels and the sampled and held first voltage level of each active pixel sensor of the selected row of active pixel sensors are then transferred to an output port of the signal conditioning and readout circuit for transfer to external circuitry. The external circuitry differentially compares the sampled and held voltage level of the plurality of voltage levels with the sampled and held first voltage level and the functionality of each active pixel sensor on the selected row of active pixel sensors, and the chain of circuitry connected to each active pixel sensor of the row of active pixel sensors is determined as a function of a difference between the sampled and held voltage level of the plurality of voltage levels and the sampled and held first voltage level.
The timing and control circuit enables evaluating performance of at least one active pixel sensor and the chain of circuitry connected to the active pixel sensor by selecting the active pixel sensor at a first time. At a second time, the second voltage level is placed at the reference distribution node of the active pixel sensor. Simultaneously, at the second time, the second voltage level is coupled to the capacitance of the photo-conversion device. The second voltage level sampled and held the within the signal conditioning and readout circuit at a third time. At a fourth time, the first voltage level is placed at the reference distribution node of the active pixel sensor and simultaneously, the first voltage level is coupled to the capacitance of the photo-conversion device at the fourth time. At a fifth time, the first voltage level from the capacitance of the photo-conversion device of the active pixel sensor sampled and held to the signal conditioning and readout circuit. The sampled and held first voltage level and the sampled and held second voltage level is transferred to an output of the signal conditioning and readout circuit for transfer to external circuitry. The external circuitry differentially compares the sampled and held first voltage level and the sampled and held second voltage level such that the difference of the sampled and held first voltage level and the sampled and held second voltage level determines performance of the active pixel sensor.
In a second embodiment the test voltage selection circuit has a first voltage distribution line containing a first distribution voltage level and a second voltage distribution line containing a second distribution voltage level. The test voltage selection circuit has a first switch. The first switch has a first terminal connected to a first voltage source that provides the first voltage level, a second terminal connected to the first voltage distribution line, a third terminal connected to the second voltage distribution line, and a control terminal connected to the timing and control circuit to selectively connect the first terminal to the second and third terminals concurrently. The test voltage selection circuit further has a second switch. The second switch has a first terminal connected to a second voltage source that provides the second voltage level, a second terminal connected to the first voltage distribution line, a third terminal connected to the second voltage distribution line, and a control terminal connected to the timing and control circuit to selectively connect the first terminal to the second and third terminals concurrently. The test voltage selection circuit has a third switch. The third switch has a first terminal connected to the first voltage source, a second terminal connected to the second voltage source, a third terminal connected to the first voltage distribution line, a fourth terminal connected to the second voltage distribution line, and a control terminal connected to the timing and control circuit to selectively connect the first terminal to the third terminal and concurrently connect the second terminal to the fourth terminal. Additionally, the test voltage selection circuit has a voltage divider. The voltage divider is connected between the first voltage distribution line, and connected to the reference distribution node of each active pixel sensor on a row of active pixel sensors for the array of active pixel sensors for distributing an incremental voltage level that varies fractionally from the first distributed voltage level present at the first voltage distribution line to the second distributed voltage level present at the second voltage distribution line. The test voltage selection circuit includes a current measuring device connected so as to measure current flowing from the first voltage source.
In the second embodiment of the test voltage selection circuit the timing and control circuit enables measurement of the average capacitance of the photo-conversion device within a group of active pixel sensors of the array of active pixel sensors by selecting the group of active pixel sensors, at a first time. During a period of time between a second time and a third time, the second switch is activated to connect the first terminal of the second switch to the second terminal and third terminal of the second switch to apply the second voltage level to the first and second voltage distribution lines and thus to the reference distribution node of each active pixel sensor of the group of active pixel sensors. Simultaneously, during the period between the second time and the third time, the second voltage level is coupled to the capacitance of the photo-conversion device of each active pixel sensor of the group of active pixel sensors to charge the capacitance to the second voltage level. During a period of time between a fourth time and a fifth time, the first switch is activated to connect the first terminal of the first switch concurrently to the second and third terminals of the first switch to apply the first voltage level to the first and second voltage distribution lines and thus to the reference distribution node of each active pixel sensor of the group of active pixel sensors. Simultaneously, during the period between the fourth and fifth time, the first voltage level is coupled to the capacitance of the photo-conversion device of each active pixel sensor of the group of active pixel sensors to charge the capacitance of the photo-conversion device to the first voltage level. The current flowing from the first voltage source to charge the capacitance of the photo-conversion device of each active pixel sensor of the group of active pixel sensors is then measured. The total capacitance of the photo-conversion devices of the group of active pixel sensors and a parasitic capacitance of the test voltage select circuit is determined by the formula: C T = I T V t CT
where
C T is the total capacitance of the photo-conversion devices and the parasitic capacitance of the test voltage select circuit,
I T is the current flowing from the first voltage source,
dv is the difference between the first voltage level and the second voltage level, and
dt CT is a charging time for the total capacitance;
The parasitic capacitance is now measured by activating the second switch to connect the first terminal of the second switch to connect the second terminal and third terminal of the second switch to apply the second voltage level to the first and second voltage distribution lines and thus to the reference distribution node of each active pixel sensor of the group of active pixel sensors, during a period of time between a sixth time and a seventh time. The first switch is then activated to connect the first terminal of the first switch concurrently to the second and third terminals of the first switch to apply the first voltage level to the first and second voltage distribution lines and thus to the reference distribution node of each active pixel sensor of the group of active pixel sensors, during a period of time between an eighth time and a ninth time. The current flowing from the first voltage source to charge the parasitic capacitance of the test voltage select circuit is then measured. The parasitic capacitance of the test voltage select circuit is determined by the formula: C P = I P V t CP
where
C P is the parasitic capacitance of the test voltage select circuit,
I P is the current flowing to the parasitic capacitance C P during charging from the second voltage level to the first voltage level,
dv is a difference between the first voltage level and the second voltage level, and
dt CP is a charging time for the parasitic capacitance,
The average capacitance of the photo-conversion device of each of the active pixel sensors of the group of active pixel sensors is determined by the formula: C FD _ = C T - C P n
where
{overscore (C FD )} is the average capacitance of the photodiode,
C T is the total capacitance,
C P is the parasitic capacitance, and
n is a number of active pixel sensors of the group of active pixel sensors.
The second embodiment of the timing and control circuit enables testing functionality of a group of at least one active pixel sensor by, at a first time, selecting the group of active pixel sensors. During a period of time between a second time and a third time, the third switch is activated to apply the first voltage level to the first voltage distribution line and to apply the second voltage level to the second voltage distribution line such that one of the incremental voltage levels is applied to the reference distribution node of each active pixel sensor of the group of active pixel sensors. Simultaneously, during the period between the second and third time, the incremental voltage level is coupled to the capacitance of the photo-conversion device of each active pixel sensor to the row of active is pixel sensors to charge the capacitance of the photo-conversion device to the incremental voltage level. The incremental voltage level present on the capacitance of the photo-conversion device of each of the active pixel sensors of the group of active pixel sensors is sampled and held within the signal conditioning and readout circuit, during a period of time between a fourth time and a fifth time. The first switch is activated to apply the first voltage level to the first voltage distribution line and the second voltage distribution line to place the first voltage level at the reference distribution node of each active pixel sensor of the group of active pixel sensors during a period of time between a sixth time and a seventh time. Simultaneously, during the period of time between the sixth time and the seventh time, the first voltage level is coupled from the reference distribution node to the capacitance of the photo-conversion device of each active pixel sensor of the group of active pixel sensors to charge the capacitance of the photo-conversion device from the incremental voltage level to the first voltage level. The first voltage level present on the capacitance of the photo-conversion device of each active pixel sensor of the group of active pixel sensors is sampled and held within the signal conditioning and readout circuit during a period of time between an eighth time and a ninth time. The sampled and held incremental voltage level present of the capacitance of the photo-conversion device of each of the active pixel sensors of the group of active pixel sensors and the sampled and held first voltage level of each of the active pixel sensors of the group of active pixel sensors are placed at an output port of the signal conditioning and readout circuit for transfer to external circuitry. The external circuitry differentially compares the sampled and held increment voltage level and the first voltage level, thus determining the functionality of each active pixel sensor of the group of active pixel sensors, and the chain of circuitry connected to each active pixel sensor of the group of active pixel sensors is determined as a function of a difference between the sampled and held incremental voltage level and the sampled and held first voltage level.
The timing and control circuit enables evaluating performance of a group of at least one active pixel sensor of the array of active pixel sensors by at a first time, selecting the group of active pixel sensors. Then during a period of time between a second time and a third time, the second switch is activated to apply the second voltage level to the voltage distribution line such that the second voltage level is applied to the reference distribution node of each active pixel sensor of the group of active pixel sensors. Simultaneously, during the period of time between the second and third time, the second voltage level is coupled to the capacitance of the photo-conversion device of each active pixel sensor to the it i row of active pixel sensors to charge the capacitance of the photo-conversion device to the second voltage level. The second voltage level present on the capacitance of the photo-conversion device of each of the active pixel sensors of the group of active pixel sensors is sampled and held within the signal conditioning and readout circuit during a period of time between a fourth time and a fifth time. During a period of time between a sixth time and a seventh time, the first switch is activated to apply the first voltage level to the first voltage distribution line and the second voltage distribution line to place the first voltage level at the reference distribution node of each active pixel sensor of the group of active pixel sensors. Simultaneously, during the period of time between the sixth time and the seventh time, the first voltage level is coupled from the reference distribution node to the capacitance of the photo-conversion device of each active pixel sensor of the group of active pixel sensors to charge the capacitance of the photo-conversion device from the incremental voltage level to the first voltage level. The first voltage level present on the capacitance of each active pixel sensor of the group of active pixel sensors is sampled and held within the signal conditioning and readout circuit during a period of time between an eighth time and a ninth time. The sampled and held second voltage level present on the capacitance of the photo-conversion device of each of the active pixel sensors of the group of active pixel sensors and the sampled and held first voltage level of each of the active pixel sensors of the group of active pixel sensors are placed at an output port of the signal conditioning and readout circuit for transfer to external circuitry. The external circuitry differentially compares the sampled and held second voltage level and the first voltage level, thus determining performance of each active pixel sensor of the group of active pixel sensors and of the chain of circuitry connected to each active pixel sensor of the group of active pixel sensors is determined as a function of a difference between the sampled and held incremental voltage level and the sampled and held first voltage level.
The group of active pixel sensors being tested for functionality, evaluated for performance and having its capacitance measured is usually a row of an array of active pixel sensors. The group of active pixel sensors can be a row of active pixel sensors placed in an area of dark pixels of the array of active pixel sensors at an edge of the array of active pixel sensors.
The evaluating performance of each active pixel sensor of the group of active pixel sensors includes evaluating range and linearity of each active pixel sensor and the chain of circuitry connected to active pixel sensor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 . is a schematic of an active pixel sensor of the prior art.
FIG. 2 . is a schematic of an active pixel sensor output signal conditioning and readout circuit of the prior art.
FIG. 3 . is a schematic of a structure of an active pixel sensor to measure the capacitance of the photo-diode of an active pixel sensor of the prior art.
FIG. 4 . is a schematic of a test system for an active pixel sensor of this invention.
FIG. 5 . is a schematic of an array of testable active pixel sensor cells of this invention.
FIG. 6 . is a schematic of an array of testable active pixel sensor cells employing a test signal voltage selection circuit for use in functional testing of an APS array for range and linearity of this invention.
FIG. 7 a . is a signal timing diagram for a method to test and verify an active pixel sensor readout chain of this invention.
FIG. 7 b . is a signal timing diagram for a method to evaluate performance an active pixel sensor readout chain of this invention.
FIG. 7 c . is a signal timing diagram for a method to measure the capacitance of the photo-conversion device of an active pixel sensor of this invention.
FIG. 7 d . is a signal timing diagram for a method to measure the the total capacitance for all the pixels on the selected row of the photo-conversion device of an active pixel sensor of this invention.
FIG. 8 . is a signal timing diagram for the method of FIG. 6 a to test and verify an active pixel sensor readout chain of this invention illustrating functional test results of an active pixel sensor readout as a function of physical location.
FIG. 9 a . is a flow diagram for a method validate functioning of an active pixel sensor readout chain of this invention.
FIG. 9 b . is a flow diagram for a method to test and verify an active pixel sensor readout chain of this invention.
FIG. 9 c . is a flow diagram for a method to evaluate performance an active pixel sensor readout chain of this invention.
FIG. 9 d . is a flow for a method to measure the capacitance of the photo-conversion device of an active pixel sensor of this invention.
DETAILED DESCRIPTION OF THE INVENTION
The new Design-for-Test (DFT) structure of the present invention is shown in FIG. 4 . The drains of the transistors M 1 and M 2 are connected respectively to the power supply distribution line V DD and the reference voltage distribution line RD, respectively. The power supply distribution line V DD is driven by a fixed voltage source set at a value equal to the power supply voltage level V DD required by the target semiconductor manufacturing process. However, instead of connecting to the same fixed voltage of V DD as described above, the RD node is switched between two external voltage levels, V 1 and V 2 , through the switches S 1 and S 2 which are implemented as CMOS switches. The clock signals controlling the activation of the switches S 1 and S 2 should be non-overlapping to prevent excess current flowing between the voltage sources supplying the voltage levels, V 1 and V 2 .
By holding the reset signal V rst high at the power supply voltage level V DD , the transistor M 2 is fully turned on. By switching the between V 1 and V 2 , where V 1 >V 2 , the current I drawn from the voltage source V 1 can be measured by the current measuring device X 1 in this test step.
Alternately, as another test approach, the reset signal V rst can be pulsed first to reset the FD node voltage through S 1 to the node voltage level of V 1 , then pulsed again to discharge the FD node through S 2 to V 2 . Since the node FD is discharged and then discharged to V 1 and V 2 through the switching sequence, there is no need to test this embodiment of an APS cell using a light source.
The effective capacitance in the area of the photosensitive element may then be calculated, which includes both the interconnect parasitic capacitance of the circuitry in the area of the RD node and the capacitance C FD of the photo-diodeD F . The effective capacitance is:
C
T
=C
P
+C
FD
where
C T is the total capacitance of the test voltage select circuit and the capacitance of the node FD.
C P is the parasitic capacitance of the test voltage select circuit.
C FD is the capacitance of the node FD of a pixel.
It is well-known in the art that the total capacitance is determined by the equation C T = I T V t
where:
I is the current measured by the current measuring device X 1 of.
dv is the difference between the voltage level V 1 and the voltage level V 2 .
dt is the period required for the capacitance C T to charge.
and the parasitic capacitance is determined by the equation: C P = I P V t
where:
I P is the current measured by the current measuring device X 1 .
dv is the difference between the voltage level V 1 and the voltage level V 2 .
dt is the period required for the capacitance C P to charge.
The net capacitance at the APS floating diffusion of the photosensitive element is therefore:
C
FD
=C
T
−C
P
As a result with the present invention's testable APS pixel circuit and above test steps, the net capacitance C FD of the photo conversion device D F can be tested and calculated without the need for an external light source.
The testable APS pixel circuit of this invention can also be incorporated with an embodiment of supporting design-for-test (DFT) structures to verify key properties of the functionality of the associated APS pixel's signal conditioning readout circuitry Sig C/R. With proper of timing of switch control signals for S 1 and S 2 , a known voltage can be established on the floating diffusion node FD just before the pixel readout operation. This known voltage undergoes the full readout operation and the corresponding output can be compared with the expected output. Any deviation of the measured output from the expected output indicates non-ideal effects along the complete readout chain. Thus the functionality such as range and linearity of the complete signal conditioning and readout chain can be verified.
The operational mode for the testable APS cell of this invention is activated by dosing switch S 1 to connect the voltage level V 1 to the read distribution line RD. During the normal operation, the voltage level V 1 is set to the level of the power supply voltage source V DD . The testable APS pixel cell is reset by turning on the transistor M 2 bringing the reset line V rst to a high level. The capacitance C FD is charged to the voltage level V 1 which turns on the transistor M 1 . The row select signal V row is then activated and the reference level of the node FD is sampled by the signal conditioning and readout circuit Sig C/R as described above. The reset signal line V rst disables the transistor M 2 . The light exposes the photodiode D F and as described above, electrons are collected at the node FD. After an integration time, the signal conditioning and readout circuit Sig C/R senses the collected charge of the node FD, conditions the signals and provides the readout as also described above.
A preferred embodiment of this functionally-testable APS pixel cell circuit invention is shown in FIG. 5 as a testable APS array subsystem. The pixel array is formed of rows and columns of interconnected testable APS cells of this invention as shown in FIG. 4 . The row decode driver circuit provides, at the appropriate time, the row select signal V row to one row of the pixel array. Each column of the testable APS cells in the pixel array is connected to a signal conditioning and readout circuit Sig C/R at the base of each column. The signal conditioning and readout circuits Sig C/R are interconnected to provide the image output signal V sig — out and the reference output signal V rs — out . The image output signal V sig — out and the reference output signal V rst — out are differentially compared to determine the intensity of light illuminating the pixel array.
The timing and control circuit provides the appropriate timing and control signals to the row decode driver and the signal conditioning and readout circuit Sig C/R during normal operation. When the test mode signal is activated to place the pixel array in the test mode, the timing and control circuit creates the appropriate timing and control signals to the test voltage select circuit to control the voltage levels V 1 and V 2 on the read voltage distribution line RD for each row of the pixel array.
In a second embodiment of the testable APS subsystem shown in FIG. 6, a resistor string R 1 , R 2 , . . . , R n−1 , and R n is used as the voltage divider to generate different voltage levels between the voltage levels V 1 and V 2 . The resistor string R 1 , R 2 , . . . , R n−1 , and R n is connected at tap points to the reference distribution node RD of each pixel cell such that each pixel cell has a unique voltage level that is a function of the location of the tap point on the resistor string R 1 , R 2 , . . . , R n−1 , and R n . Therefore the voltage levels that will be fed to the pixel RD nodes are predetermined and known, provided that the two terminal voltages are known. Connecting to the resistor string R 1 , R 2 , . . . , R n−1 , and R n at intervals has several advantages. One advantage is to reduce the RC time constant so each node can settle faster. In addition, the voltage step between the neighboring APS pixel cells is larger so the effect of circuit noise on signal integrity and test accuracy is reduced.
To verify the signal conditioning and readout circuit Sig C/R functionality in this test step, the voltages V 1 and V 2 should be set to different levels. In normal implementations of this test approach in order to satisfy design practice requirements of typical semiconductor manufacturing processes, both V 1 and V 2 should be less than one transistor threshold below the supply voltage to ensure that when M 2 is turned on, M 2 is in the linear region of operation and the voltage on RD can be driven or passed on to the FD node.
The signal timing diagram of FIG. 7 a illustrates timing signals created by the timing and control circuit of FIG. 6 during normal operation. At the time t 0 , the timing and control circuit provides a signal to the row decoder driver to select a row of pixels by changing the row select signal V row from a low voltage level (0V) to a high voltage level (V DD ). The switch S 1 is activated such that the reference distribution line RD of each pixel of the selected row of pixels is set at voltage level V 1 . For normal operation, the voltage level V 1 is set to the power supply voltage level (V DD ).
At the time T 1 , the reset signal V rst changes from the low voltage level (0V) to the high voltage level (V DD ) to activate the transistor M 2 and charge the capacitance C FD of the node FD to the voltage level V 1 . The voltage level V 1 acts as a reference voltage level for the operation.
Since the row select signal V row is set to the voltage level (V DD ) and the node FD is also at the voltage level (V DD ), the transistors M 1 and M 3 are turned on and the voltage V out — pixel at the output of the pixel is set to the power supply voltage level (V DD ).
At the time t 2 , the reset signal changes from the high voltage level (V DD ) to the to the low voltage level (0V) to deactivate the transistor M 2 . The reference sample and hold signal SHR is changed from the low voltage level (0V) to the high voltage level (V DD ) to activate the sampling of the voltage signal present on the column bus ColBus. The sampling of the voltage on the column bus ColBus is completed at time t 4 .
The reset signal V rst changes from the low voltage level (0V) to the high voltage level (V DD ) at time t 5 to again turn on the transistor M 2 and charge the capacitance C FD at the node FD to the reference voltage level V 1 . At the time t 6 , the reset signal changes from the high voltage level (V DD ) to the low voltage level (0V) to deactivate the transistor M 2 .
In the time interval t 6 to t 7 , the light impinging upon the photodiode DF causes the photo-generated electrons to modify the voltage level of the node FD which is translated through the source-follower transistor M 1 to the output voltage level V out — pixel .
At the time t 7 , the sense sample hold signal SHS changes from a low voltage level (0V) to a high voltage level (V DD ) to activate the signal conditioning and readout circuit to acquire the voltage level indicating the level of light impinging on the pixel.
The signal timing diagram of FIG. 7 b illustrates the timing of the signals necessary to verify the functioning of the signal conditioning and readout circuit Sig C/R of FIG. 6 and evaluate the pixel signal of each pixel within a row to insure proper operation of each signal. The method of verification of functionality and evaluating proper operation begins at the time t 0 by changing the row select signal for the chosen row from the low voltage level (0V) to the high voltage level (V DD ) to turn on transistor M 3 . At time t 1 , the switch S 3 is activated to apply the voltage level V 1 to the voltage distribution line DFTN 1 and the voltage level V 2 to the voltage distribution line DFTN 2 . Applying the voltage level V 1 to the voltage distribution line DFTN 1 and the voltage level V 2 to the voltage distribution line DFTN 2 cause the resistor string R 1 , R 2 , . . . , R n−1 , R n to act as a voltage divider. Also at the time t 1 , the reset signal V rst changes from the low voltage level (0V) to the high voltage level (V DD ) to turn on the transistor M 2 . Thus the voltage to each pixel of the row is incrementally varied from the voltage level V 1 to the voltage level V 2 .
Since the row select signal has turned on, the pixel output voltage V out — pixel rises to a voltage level that is a voltage threshold level of the transistor M 2 less than the voltage level present at the node FD.
At the time t 2 , the switch S 3 is deactivated and the reset signal V rst changes from the high voltage level (V DD ) to the low voltage level (0V) turning off the transistor M 2 . At the time t 3 , the sense sample and hold signal SHS changes from the low voltage level (0V) to the high voltage level (V DD ) to cause the signal conditioning and readout circuit Sig C/R to sample and retain the voltage V out — pixel present at the output of the pixel. At the time t 4 , the sense sample and hold signal SHS changes from the high voltage level (V DD ) to the low voltage level (0V) to deactivate the signal conditioning and readout circuit Sig C/R.
At the time t 5 , the switch S 1 is activated to apply the voltage level V 1 to the reference voltage node RD of each pixel of the selected row. Also at time t 5 , the reset signal V rst changes from the low voltage level (0V) to the high voltage level (V DD ) to turn on the transistor M 2 and allow the capacitance C FD at the node FD to charge to the voltage level V 1 and thus allowing the voltage level V out — pixel at the output of the pixel to reach a voltage level that is a threshold voltage V T less than the voltage level V 1 .
The reset signal change from the high voltage level (V DD ) to the low voltage level (0V) to deactivate the transistor M 2 and the switch S 1 is deactivated at the time t 6 .
The reference sample and hold signal SHR changes from the low voltage level (0V) to the high voltage level (V DD ) at the time t 7 to activate the signal conditioning and readout circuit Sig C/R to sample and retain the reference voltage level. The reference sample and hold signal SHR is changed from the high voltage level (V DD ) to the low voltage level (0V) at the time t 8 . The sensed signal output V sig — out and the reference signal output V rst — out are differentially compared to determine the voltage that is present at each node FD of each pixel. Since the voltage at each node FD of each pixel varies incrementally from the voltage level V 2 to the voltage level V 1 , the output voltage of the signal conditioning and readout circuit Sig C/R will vary incrementally, dependent on the position of the connection of each to the resistor string R 1 , R 2 , . . . , R n−1 , R n . Since the values of the voltage level V 1 and V 2 are known, the linearity and functioning of the pixel and the intermediate circuitry can be determined. FIG. 8 shows the results of testing a row of pixels as described above. As each pixel in the row is evaluated, the voltage level is recorded according to its position on the row. As is shown, the voltage level varies incrementally between zero volts and the difference between the voltage levels V 1 and V 2 depending on its position in the row and its connection location to the resistor string R 1 , R 2 , . . . , R n−1 , R n .
FIG. 7 c illustrates the timing diagram of the testable APS array of this invention to evaluate the performance and linearity of the pixel array and the signal conditioning and readout circuit Sig C/R. At the time t 0 , the row select signal changes from the low voltage level (0V) to the high voltage level (V DD ) to activate the transistor M 3 of each pixel on the selected row. At the time t 1 , the switch S 2 is activated to place the voltage level V 2 at the reference distribution node RD of each pixel of the selected row. The voltage level V 2 is chosen to emulate the voltage level achieved during the exposure of the photodiode DF to impinging light. Also at the time t 1 the reset signal V rst changes from the low voltage level (0V) to the high voltage level (V DD ) to turn on the transistor M 2 such that the capacitance C FD at the node FD is charged to the voltage level V 2 . The switch S 2 is deactivated and the reset signal V rst is changed from the high voltage level (V DD ) to from the low voltage level (0V) to turn off the transistor M 2 .
The voltage V out — pixel present at the output of the pixel is to be set to a threshold voltage V T lower than the voltage level V 2 . At the time t 3 , the sense sample and hold signal SHS is activated such that the signal conditioning and readout circuit Sig C/R is activate to capture and retain the voltage level V out — pixel . At the time t 4 , the sense sample and hold signal SHS changes from the high voltage level (V DD ) to from the low voltage level (0V) to deactivate the signal conditioning and readout circuit Sig C/R.
At the time t 5 , the switch S 1 is activated to place the voltage level V 1 at the reference distribution node RD of each pixel of the row of the row of pixels. Also at time t 5 , the reset signal V rst changes from the low voltage level (0V) to the high voltage level (V DD ) to activate the transistor M 2 so as to charge the capacitance C FD at the node FD to the voltage level V 1 . The voltage level V out — pixel at the output of the pixel thus rises to a voltage level that is a threshold voltage V T less than the voltage level V 1 . At the time t 6 , the switch S 1 is deactivated and the reset signal V rst changes from the high voltage level (V DD ) to the low voltage level (0V) turning off the transistor M 2 .
The reference sample and hold signal SHR changes from the low voltage level (0V) to the high voltage level (V DD ) at time t 7 to activate the signal conditioning and readout circuit Sig C/R to capture the reference voltage level at the output of the pixel V out — pixel . At the time t 8 , the reference sample and hold signal SHR changes from the high voltage level (V DD ) to the low voltage level (0V) to deactivate the signal conditioning and readout circuit Sig C/R.
The reference output signal V rst — out and the sense output signal V sig — out are differentially compared to determine the performance of the total chain of circuitry from the pixel to the column bus ColBus to the signal conditioning and readout circuit Sig C/R. The voltage level difference between reference output signal V rst — out and the sense output signal V sig — out represents the magnitude of the voltage difference between the voltage level V 1 and the voltage level V 2 . The voltage level differences of the reference output signal V rst — out and the sense output signal V sig — out for each pixel on the selected row of pixels are recorded, and operational parameters such as linearity and range for each testable APS cell of the selected row of pixels, each column bus ColBus and signal conditioning and readout circuit Sig C/R are extracted from the recorded voltage level differences.
The testable APS cell coupled to the test voltage select circuit TestVSelect of FIG. 6 is used to measure the total capacitance C FD of the row of pixels. Referring to FIG. 6, the voltage sources V S 1 and V S 2 provide the voltage levels V 1 and V 2 to the test voltage select circuit. In series with the voltage source V S 1 is a current measuring device X 1 to determine the current I flowing from the voltage source V S 1 to the test voltage select circuit. Refer to FIG. 7 d for the description of the method to measure the total capacitance C FD for all the pixels on the selected row. The row select signal is held at the low voltage level (0V) to keep the transistor M 2 turned off. At the time t 0 , the reset signal V rst changes from the low voltage level (V0) to the high voltage level (V DD ) to activate the transistor M 2 of each APS pixel cell. At the time t 1 , the switch S 2 is activated to place the voltage level V 2 at the reference distribution node RD of each pixel on the row of pixels. Once all the capacitances C FD at the node FD of each pixel is charged to the voltage level V 2 , the switch S 2 is deactivated at the time t 2 . The switch S 1 is activated at the time t 3 to place the voltage level V 1 at the reference distribution node RD of each pixel. As the capacitance C FD of all the pixels on the selected row are charged, the current I is recorded by the current measurement device X 1 of FIG. 6 . When all the capacitances C FD of the node FD of all the pixels have charged to the voltage level V 1 , the switch S 1 is deactivated at the time t 5 .
The total capacitance charged is the parasitic capacitance of the test voltage select circuit and the capacitance C FD of the node FD of all the pixels as shown by the equation: C T = C P + ∑ n 1 C FD
where
C T is the total capacitance of the test voltage select circuit and the capacitance of the node FD.
C P is the parasitic capacitance of the test voltage select circuit.
C FD is the capacitance of the node FD of a pixel.
n is the number of pixels on the selected row.
It is well-known in the art that the total capacitance is determined by the equation: C T = I T V t
where:
I is the current measured by the current measuring device X 1 of FIG. 6 .
dv is the difference between the voltage level V 1 and the voltage level V 2 .
dt is the period required for the capacitance to charge or the time elapsed from the time t 3 to t 4 .
If the transistor M 2 of all the pixels on a selected row of pixels is turned off and the previous method of setting the voltage at the reference distribution node RD of each pixel to the voltage level V 2 , then to the voltage level V 1 , and then observing the charging current I is followed, the parasitic capacitance C P of the test voltage select circuit can then be determined. To accomplish this, the reset signal V rst is changed from the high voltage level (V DD )to the low voltage level (0V) at the time t 6 to deactivate the transistor M 2 of all the pixels of the selected row of pixels. At the time t 7 , the switch S 2 is activated to place the voltage level V 2 at the reference distribution node RD of all of the pixels. When the parasitic capacitance C P of the test voltage select circuit is charged to the voltage level V 2 , the switch S 2 is deactivated at the time t 8 . At the time t 9 , the switch S 1 is activated to charge the parasitic capacitance C P of the test voltage select circuit from the voltage level V 2 to the voltage level V 1 . The current I from the voltage source V S 1 is measured by the current measurement device X 1 . When the reference distribution node RD of all of the pixels on the selected row are charged to the voltage level V 1 , the switch S 1 is deactivated.
The parasitic capacitance C P is determined by the equation: C P = I P V t
where:
I P is the current measured by the current measuring device X 1 of FIG. 6 .
dv is the difference between the voltage level V 1 and the voltage level V 2 .
dt is the period required for the capacitance to charge or the time elapsed from the time t 9 to t 10 .
The total capacitance C FD — TOT of the nodes FD of all the pixels then is determined by the equation:
C
FD
—
TOT
=C
T
−C
P
The average node capacitance {overscore (C FD )} of the nodes FD of all the pixels then is determined by the equation: C FD _ = C T - C P n
The testable APS cell of this invention, as described above, is configured as an array of testable APS cells. A row of the testable APS cells can be placed at the edge of an array of APS cells of the prior art. The row of testable APS cells are placed at the edge of the array opposite the signal conditioning and readout circuit Sig C/R.
Further, the peripheral rows of APS cells are marked to prevent light from impinging on the photodiodes D F of the APS cell. These are commonly referred to as “dark” pixels.
Since no external light source is needed to verify the functionality of the testable APS and associated readout circuit of this invention, there is no need for optical setup during this particular testing phase of the testable APS pixel circuits. An advantage of the part of the present invention's test steps is that it can be used to pre-screen the APS sensor chips, and, when found by these test steps, to reject the chips with defective APS cell and readout circuitry before they undergo the final optical test. In addition, a row of selected testable APS pixel cells can be placed as part of the “dark” pixels surrounding the active pixel array, typically as the top-most or bottom-most row, since the resistor string needs to be close by. Another advantage of this invention is that, in this approach of this embodiment of the invention, the array regularity needed for layout and routing chip physical design and area efficiency is preserved since the additional routing is outside of the pixel array.
In summary, one advantage of this invention is that the photosensitive element and parasitic capacitance test measurement can be done in a dark environment. This allows the testable APS cells required for test and measurement of APS imaging products to be part of the “dark” pixels used to measure and project reliability and functional quality of an overall sensor chip. A further advantage is that the DFT structure of this invention enables the measurement and verification of the testable APS pixel readout circuit functionality without the need to use a dedicated optical sensor and associated design and test circuitry.
Refer now to FIGS. 9 a - 9 d to discuss the method to verify performance of a row of active pixel sensors. The steps of the method as shown in FIG. 9 a are to test the functionality 100 of each APS on the selected row of APS's and the chain of circuitry connected to the APS's on the row of APS's. The chain of circuitry tested is the column bus connected to each APS of a column of APS's of FIG. 4 and the signal conditioning and readout circuit Sig C/R of FIG. 4 . The next step of the method of this invention evaluates the performance 200 of each APS of the selected row of APS's and the chain of circuitry connected to each APS. The evaluation of the performance determines the range and linearity of the APS and the connected chain of circuitry to insure the accurate determination of the light impinging on the APS's.
The next step of the method of this invention is the determination of an average capacitance per APS for a row of APS's.
The sequential order of the steps of the method of this invention is not unique. The steps may be performed in any order. Further, the method for verifying performance may include only one of the steps as listed or any combination of the steps as shown.
Refer now to FIG. 9 b for a discussion of the testing of the functionality 100 of a row of APS's and the chain of circuitry connected to each APS. The row of APS's whose functionality is to be tested are selected 105 . In FIG. 4 the row select signal V row is activated to connect each APS on the row to the column bus and through the column bus to the signal conditioning and readout circuit SIG C/R. The capacitance C FD of the photodiode D F of each APS of a selected row of APS's of FIG. 6 is charged 110 to one of a group of incremental voltages. These incremental voltages vary from the voltage level V 2 to the voltage level V 1 as above-described and are formed by the voltage divider created by the resistor string R 1 , R 2 , . . . , R n−1 , R n of FIG. 6 .
To charge the capacitance C FD to the incremental voltage level, the switch S 3 is activated to place the first voltage distribution line DFTN 1 and the second voltage level V 2 on the second voltage distribution line DFTN 2 . The voltage divider formed by the resistor string R 1 , R 2 , . . . , R n−1 , R n then forms the incremental voltages. At the time the switch S 3 is activated, the reset signal V rst turns on the transistor M 2 to allow the capacitance C FD to charge to the incremental voltage level present at the reference distribution node RD.
The incremental voltage present on the capacitance C FD is buffered by the source follower formed by the transistor M 1 such that the output signal V out — pixel at the output of the APS is approximately a threshold voltage V T lower than the incremental voltage present at the capacitance C FD .
The voltage V out — pixel at the output of the APS representing the magnitude of the voltage that has charged the capacitance C FD is sampled and held 115 by the signal conditioning and readout circuit SIG C/R.
The capacitance C FD of the photodiode D FD of each APS of the row of selected APS's is now charged 120 to the voltage level V 1 . To accomplish this, the switch S 1 of FIG. 6 is activated to place the first voltage level V 1 on the voltage distribution lines DFTN 1 and DFTN 2 , and thus to the reference distribution node RD. At this same time, the reset signal V rst turns on the transistor M 2 to charge the capacitance C FD to the voltage level V 1 .
The voltage level V 1 present on the capacitance C FD is buffered by the source follower formed by the transistor M 1 such that the output signal V out — pixel at the output of the APS is approximately a threshold voltage level V T lower than the voltage level V 1 present at the capacitance C FD .
The voltage V out — pixel at the output of the APS representing the magnitude of the voltage that has charged the capacitance C FD is sampled and held 125 by the signal conditioning and readout circuit SIG C/R.
The sampled and held incremental voltage and the sampled and held voltage level V 1 are differentially compared 130 to form a difference signal. The magnitude of the difference signals of the APS's on the selected row of APS's are compared to determine 135 that all the APS's of the selected row of APS's are functioning and the chain of circuitry connected to each APS is also functioning.
Refer now to FIG. 9 c for a discussion of evaluating performance 200 of a row of APS's and the chain of circuitry connected to each APS. The row of APS's whose functionality is to be tested are selected 205 . In FIG. 4 the row select signal V row is activated to connect each APS on the row to the column bus and through the column bus to the signal conditioning and readout circuit SIG C/R. The capacitance C FD of the photodiode D FD of each APS of a selected row of APS's of FIG. 6 is charged 210 to the voltage level V 2 .
To charge the capacitance C FD to the voltage level V 2 , the switch S 3 is activated to place the voltage level V 2 on the first and second voltage distribution lines DFTN 1 and DFTN 2 . At the time the switch S 3 is activated, the reset signal V rst turns on the transistor M 2 to allow the capacitance C FD to charge to the voltage level V 2 present at the reference distribution node RD.
The voltage level V 2 present on the capacitance C FD is buffered by the source follower formed by the transistor M 1 such that the output signal V out — pixel at the output of the APS is approximately a threshold voltage V T lower than the voltage level V 2 present at the capacitance C FD .
The voltage V out — pixel at the output of the APS representing the magnitude of the voltage that has charged the capacitance C FD is sampled and held 215 by the signal conditioning and readout circuit SIG C/R.
The capacitance C FD of the photodiode D FD of each APS of the row of selected APS's is now charged 220 to the voltage level V 1 . To accomplish this, the switch S 1 of FIG. 6 is activated to place the first voltage level V 1 on the voltage distribution lines DFTN 1 and DFTN 2 , and thus to the reference distribution node RD. At this same time, the reset signal V rst turns on the transistor M 2 to charge the capacitance C FD to the voltage level V 1 .
The voltage level V 1 present on the capacitance C FD is buffered by the source follower formed by the transistor M 1 such that the output signal V out — pixel at the output of the APS is approximately a threshold voltage level V T lower than the voltage level V 1 present at the capacitance C FD .
The voltage V out — pixel at the output of the APS representing the magnitude of the voltage that has charged the capacitance C FD is sampled and held 225 by the signal conditioning and readout circuit SIG C/R.
The sampled and held voltage level V 2 and the sampled and held voltage level V 1 are differentially compared 230 to form a difference signal. The magnitude of the difference signals of the APS's on the selected row of APS's are compared to determine 235 the performance of each of the APS's of the selected row of APS's and the chain of circuitry connected to each APS. By evaluating the difference voltages, the linearity of the APS's and the attached chain of circuitry is determined.
From the measure of the linearity of the APS's of an array of APS's, the intensity of the light impinging upon the array of APS's can be more accurately determined.
The method for determining 300 an average capacitance C FD per APS of the row of APS's within the array of APS's is first selected 305 . In this case, the row select signal V row may or may not be activated to turn on the transistor M 3 of FIG. 4 .
The total capacitance C T is defined as the capacitance C FD of the photodiodes D FD of all of the APS's on the selected row and the parasitic capacitances C P1 and CP 2 (referred to hereinafter in total as C T of the test voltage select circuit of FIG. 6 . The total capacitance C T is charged 310 to the voltage level V 2 . The switch S 2 of the test voltage select circuit of FIG. 6 is activated to apply the voltage level V 2 to the first and second voltage distribution lines DFTN 1 and DFTN 2 , and thus to the reference distribution nodes RD of all of the APS's on the selected row. The parasitic capacitance C T is now charged to the voltage level V 2 . The voltage reset signal V rst is simultaneously activated to turn on the transistor M 2 to couple the voltage level V 2 to the capacitance C FD of the photodiode D FD . The switch S 2 and the reset signal V rst are deactivated at the completion of the charging 310 of the total capacitance C T to the voltage level V 2 .
Next, the total capacitance C T is charged 315 from the voltage level V 2 to the voltage level V 1 . The switch S 1 is activated to apply the voltage level V 1 to the first and second voltage distribution lines DFTN 1 and DFTN 2 , and thus to the reference distribution nodes RD of all of the APS's on the selected row. The parasitic capacitance C P is now charged to the voltage level V 1 . The reset signal V rst is simultaneously activated to turn on the transistor M 2 to couple the voltage level V 1 to charge the capacitance C FD of the photodiode D FD to the voltage level V 1 .
While the total capacitance C T is being charged, the current determining device X 1 measures 320 the current I T flowing to the total capacitance C T . Further, the charging period t CT to charge the total capacitance C T is measured 325 .
The total capacitance C T is calculated 330 by the formula: C T = I T V t CT
where
C T is the total capacitance,
I T is the current flowing to the total capacitance,
C T during charging from the voltage level V 2 to the voltage level V 1 ,
dv is the difference between the voltage level V 1 and the voltage level V 2 , and
dt CT is the charging period of the total capacitance C T .
The parasitic capacitance C P is charged 335 to the voltage level V 2 . The switch S 2 of the test voltage select circuit of FIG. 6 is activated to apply the voltage level V 2 to the first and second voltage distribution lines DFTN 1 and DFTN 2 , and thus to the reference distribution nodes RD of all of the APS's on the selected row. The parasitic capacitance C P is now charged to the voltage level V 2 . The voltage reset signal V rst is not activated to turn on the transistor M 2 to couple the voltage level V 2 to the capacitance C FD of the photodiode D FD . The switch S 2 is deactivated at the completion of the charging 335 of the parasitic capacitance C P to the voltage level V 2 .
Next, the parasitic capacitance C P is charged 340 from the voltage level V 2 to the voltage level V 1 . The switch S 1 is activated to apply the voltage level V 1 to the first and second voltage distribution lines DFTN 1 and DFTN 2 , and thus to the reference distribution nodes RD of all of the APS's on the selected row. The parasitic capacitance C P is now charged to the voltage level V 1 .
The reset signal V rst again is not activated to turn on the transistor M 2 and the voltage level V 1 is not coupled to the capacitance C FD of the photodiode D FD to the voltage level V 1 .
While the parasitic capacitance C P is being charged, the current determining device X 1 is measuring 345 the current I P flowing to the parasitic capacitance C P . Further, the charging period t CP to charge the parasitic capacitance C P is measured 350 .
The parasitic capacitance C P is calculated 355 by the formula: C P = I P V t CP
where
C P is the parasitic capacitance,
I P is the current flowing to the parasitic capacitance C P during charging from the voltage level V 2 to the voltage level V 1 ,
dv is the difference between the voltage level V 1 and the voltage level V 2 , and
dt CP is the charging period of the total capacitance C P .
The average capacitance {overscore (C FD )} of the photodiode of the selected row of APS's is calculated 360 by the formula: C FD _ = C T - C P n
where
{overscore (C FD )} is the average capacitance of the photodiode,
C T Is the total capacitance,
C P is the parasitic capacitance, and
n is the number of APS's in the selected row of APS's.
The method as described in FIG. 9 a generally selects a row for verifying performance of the APS's. It is in keeping with the intent of this invention that any convenient grouping of APS's can be selected for verifying performance. Further, it is apparent to those skilled in the art that the grouping of APS's may contain any number of APS's. An individual APS may be selected to verify performance.
While this invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention. Reversing the polarities of the silicon materials implanted in a integrated circuit implementation of the DFT APS can easily form a corresponding active pixel sensor circuit with the roles of P-type and N-type CMOS devices reversed. The operational voltage biases and the signal levels shown in each of the figures will also be reversed appropriately. | Apparatus and methods for testing an active pixel sensor ensure that a signal proportional to the quantity of light energy impinging on the active pixel sensor is reliably and accurately captured and made available for further on processing the rest of the APS system circuitry. The apparatus and method determines the capacitance of a photo-conversion device of the active pixel sensor. The apparatus and method determines that an active pixel sensor is functioning correctly. The apparatus and method determines the performance of an active pixel sensor. Where the performance of the active pixel sensor is a measure of linearity of the active pixel sensor and a connected chain of circuitry that process the signal converted by the photo-conversion device of the active pixel sensor. | 7 |
This application is a continuation of application Ser. No. 08/387,011, filed Feb. 10, 1995, now U.S. Pat. No. 5,556,771.
FIELD OF THE INVENTION
This invention relates to the fields of molecular biology, nucleic acid amplification and stabilized biological compositions generally. In particular, the present invention relates to a stable lyophilized enzyme composition containing one or more nucleic acid polymerases.
BACKGROUND OF THE INVENTION
Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are large linear macromolecules composed of covalently-linked nucleotide subunits. DNA is usually found in a "double-stranded" form in which two DNA chains are associated by hydrogen bonding in an antiparallel fashion. RNA usually exists in nature as a single polynucleotide chain. Nucleotides are molecules having a sugar (either deoxyribose or ribose) and a nitrogenous base moiety, and are usually connected together in nucleic acids by a phosphodiester linkage. There are five common nitrogenous bases. Three are found in both DNA and RNA: these are adenine (A), guanine (G) and cytosine (C). The other two, thymine (T) and uracil (U), are specific to DNA and RNA, respectively.
Most (if not all) of every organism's genetic information is transmitted from one generation to the next in the form of DNA or RNA. This information is conveyed in the sequence of the nucleotides along a single nucleic acid chain or "strand", which constitutes a genetic code. Moreover, each of the nitrogenous bases of a nucleic acid strand has the ability to specifically hydrogen bond with one or more other nitrogenous bases of the same or a different nucleic acid strand. Thus, under usual conditions, A hydrogen bonds with T (or U), and C hydrogen bonds with G; this specific hydrogen-bonding is called base-pairing. In double-stranded DNA each of the two strands consists of a chain of nucleotides in which most or all of the nucleotides are base-paired with nucleotides of the other strand. In such a case, the order of nucleotides on one DNA strand determines the order of nucleotides on the other DNA strand. Two nucleic acid strands which are "mirror images" of each other in this way are said to be perfectly complementary.
Nucleic acids are synthesized in vivo by a mechanism exploiting the fact that each nucleic acid strand dictates the order of nucleotides of a perfectly complementary strand; this remains true whether the desired nucleic acid is RNA or DNA, and regardless whether the nucleic acid to be used as a template is RNA or DNA. Most of the specific mechanisms for DNA replication involve the use of a DNA polymerase to sequentially add nucleotides to a 3' hydroxyl group of a polynucteotide primer hydrogen-bonded to the template nucleic acid strand. The newly added nucleotides are chosen by the DNA polymerase based on their ability to base-pair with the corresponding nucleotide of the template strand. This process of adding nucleotides to one end of a primer is sometimes called primer extension.
Unlike DNA synthesis, RNA synthesis does not normally require the existence of a polynucleotide primer. Rather, RNA synthesis is usually mediated by an RNA polymerase which recognizes one or more specific nucleotide sequences of a nucleic acid template. The region of the template to which the RNA polymerase binds, called a promoter, is usually double-stranded. After binding to the promoter, the RNA polymerase "reads" the template strand and synthesizes a covalently-linked polyribonucleotide strand complementary to the template. RNA polymerases from different organisms preferentially recognize different promoter sequences.
DNA and RNA polymerase enzymes have been purified from a number of diverse organisms. Some of these enzymes, such as E. coli DNA polymerase I, the Klenow fragment of DNA polymerase I, and various RNA polymerases are commonly used in vitro as tools in molecular biology and nucleic acid biochemistry research. See generally e.g., Sambrook et al., Molecular Cloning: A Laboratory Manual (2d ed. Cold Spring Harbor Press 1989).
Another use for nucleic acid polymerases has arisen with the advent of various methods of nucleic acid amplification, such as the polymerase chain reaction (PCR), see e.g., Mullis et al., U.S. Pat. Nos. 4,683,195, 4,683,202, and 4,800,159. In the simplest form of PCR, two oligonucleotide primers are synthesized, each primer complementary to a region of a target nucleic acid positioned to the 3' side, with respect to the target nucleic acid, of a target nucleotide sequence region. Each primer is complementary to one of two complementary nucleic acid strands; the target region comprises a nucleotide sequence region encompassing both nucleic acid strands of a double-stranded target nucleic acid. When these primers are allowed to hydrogen-bond ("hybridize") with the substrate and a DNA polymerase is added to the reaction mixture along with nucleotide triphosphates, each hybridized primer is extended by the enzyme in a 5'→3' direction. The reaction mixture is then heated to melt the primer extension product:template hybrid, the temperature is decreased to permit another round of primer/target hybridization, and more DNA polymerase is added to replace the DNA polymerase inactivated by the high temperature step. By repeating the process through a desired number of cycles, the amount of nucleic acids having the target nucleotide sequence is exponentially increased. More recently, a thermostable DNA polymerase derived from Thermus aquaticus has been successfully used in the PCR method to lessen the need for repeated addition of large amounts of expensive enzyme. The Taq polymerase resists inactivation at 90°-95° C., thus obviating the need for repeated additions of enzyme after each round of strand separation.
Other methods of nucleic acid amplification have been devised, such as those using RNA transcription as a step in the amplification process. One such method functions by incorporating a promoter sequence into one of the primers used in the PCR reaction and then, after amplification by the PCR method, using the double-stranded DNA as a template for the transcription of single-stranded RNA by a DNA-directed RNA polymerase, see e.g., Murakawa et al., DNA 7: 287-295 (1988)).
Other amplification methods use multiple cycles of RNA-directed DNA synthesis and transcription to amplify DNA or RNA targets, see, e.g., Burg et al,, WO 89/1050; Gingeras et al., WO 88/10315 (sometimes called transcription amplification system or TAS); Kacian and Fultz, EPO Publication No. EPO 408,295 (which enjoys common ownership with the present application); Davey and Malek, EPO Application No. 88113948.9; Malek et al., WO91/02818). These methods make use of an enzyme, reverse transcriptase (RT), which can use RNA or DNA as a template for synthesis of a complementary DNA strand. Some of these methods also utilize cellular RNAse H activity as an essential component. Most retroviral reverse transcriptases, such as those encoded by Moloney Murine Leukemia Virus (MMLV) and Avian Myeloblastosis Virus (AMV), possess an RNA-directed DNA polymerase, a DNA-directed DNA polymerase activity as well as RNaseH activity. RNAse H activity selectively degrades the RNA strand of an RNA:DNA hybrid nucleic acid molecule, thus allowing the amplification reaction to proceed without the need for temperature cycling.
Nucleic acid amplification is an increasingly popular tool for the specific identification and/or amplification of unique or characteristic nucleic acid segments in a variety of settings. Thus, nucleic acid amplification is used in food and agricultural testing, medical diagnostics, human genetic testing and counseling, archeology, and criminal forensics. Because these methods all utilize enzymes, methods of producing, packaging, transporting and storing large quantities of highly active enzymes has become an issue of critical importance in the manufacture, marketing and sale of enzymes and kits for nucleic acid amplification. Specifically, for methods employing transcription-based amplification, commercially acceptable methods and preparations for storing active preparations of reverse transcriptase and RNA polymerase are necessary for the successful manufacture and marketing of kits for nucleic acid amplification.
The usual method of stabilizing reverse transcriptase and RNA polymerase enzymes (as well as many other enzymes used in molecular biology research) is by storing a liquid preparation of each enzyme in a solution containing 50% (v/v) glycerol and a reducing agent such as dithiothreitol (DTT) or β-mercaptoethanol (βME) at -20° C. This method preserves the activity of the enzymes for many months with little loss of activity. By contrast, enzyme activities are readily lost when the enzymes are stored at room temperature or at 4° C. These preparations are generally shipped from the enzyme supplier to the end user in dry ice; losses of 30% or more of enzyme activity are common during such transport due to freezing and thawing of the enzyme preparation. These enzymes are formulated and supplied separately.
A method of storing and shipping reverse transcriptase and RNA polymerase without the need for refrigeration would obviate the necessity for refrigerated transport and/or methods of cold storage such as dry ice, wet packs, dry packs, or styrofoam shipping containers. Such methods would also be more cost effective, since the production overhead associated with these methods of maintaining enzyme activity would be unnecessary. Methods of storing enzymes which would allow the enzyme preparation to tolerate a limited exposure to higher temperatures would eliminate the losses in enzyme activity which could result if the enzyme preparation sits on a loading dock or in a truck during shipment. Such a method would have to be highly reproducible. Moreover, if the enzymes could be provided in a single container in a form compatible with their intended use (such as in a formulation containing all or most of any necessary co-factors and substrates) such a preparation would be more economical to manufacture and more convenient to use.
Freeze-drying (lyophilization) has been used to preserve foods, biological membranes, whole cells (see. e.g., American Society for Microbiology, Manual of Methods for General Bacteriology 210-217 (1981), and biological macromolecules including enzymes. Lyophilization involves the removal of water from a frozen sample by sublimation under lowered pressure. Sublimation is the process by which a solid is evaporated without passing through the liquid stage.
The theoretical aspects of lyophilization are complex. It is thought that When a biological substance such as a protein is in aqueous solution the molecule is surrounded by a hydration shell comprising water molecules; this hydration shell stabilizes the protein and helps maintain its activity. When water is removed, the protein's reactive groups, which are normally masked by the hydration shell, are free to react with each other, thus forming new, essentially irreversible bonds. These bonds can distort the protein's native conformation. Also, new hydrophobic/hydrophilic interactions may take place in the absence of water which also can distort the conformation of the protein. Since the three-dimensional conformation of many proteins confers a biological activity, the distortion of the conformation can alter biological activities upon drying. By the same mechanism, cross-linking and aggregation of proteins can occur.
Freezing a protein sample prior to drying helps reduce the degree of conformational distortion due to drying. The lowered initial temperature helps keep unwanted reactions between amino acid reactive groups to a minimum by depriving the reactants of energy. At the same time, while in a frozen state the protein has less stearic freedom than when in solution and is less prone to gross conformational change.
However, completely dried lyophilizates tend to have a shorter "shelf" or storage life than do incompletely dried lyophilizates still containing a low percentage of water. Such incompletely dried lyophilizates must often be stored at temperatures no higher than about 4°-10° C., and are still capable of undergoing inactivating chemical reactions that would not be possible were water not present. Thus, while the shelf life of many incompletely dried lyophilized biologically active proteins is longer than those that are completely dried, it is still necessary to refrigerate the preparation in order to maintain activity. Even so, there is a loss of activity in such preparations over a relatively short period of time. Moreover, some enzymes, such as phosphofructokinase, are completely inactivated after lyophilization in the absence of a cryoprotectant, regardless of whether the preparation is completely dried or not. See e.g., Carpenter et al., Cryobiology 25: 372-376 (1988).
As used herein, the term "cryoprotectant" is intended to mean a compound or composition which tends to protect the activity of a biologically active substance during freezing, drying, and/or reconstitution of the dried substance.
The term "stabilizing agent" is meant to mean an agent that, when added to a biologically active material, will prevent or delay the loss of the material's biological activity over time as compared to when the material is stored in the absence of the stabilizing agent.
A variety of cryoprotectant additives have been used or proposed for use as excipients to help preserve biological activity when biological materials, including particular proteins, are dried. Clegg et al., Cryobiology 19: 106-316 (1982) have studied the role of glycerol and/or trehalose in the ability of cysts of the brine shrimp Artemia to remain viable after desiccation. Carpenter et al., Cryobiology 24: 455-464 (1987), report that the disaccharides maltose, sucrose, lactose and trehalose can play a role in increasing the stabilization of phosphofructokinase activity in a purified enzyme preparation subjected to air-drying. EPO Publication No. 0431882A2, discloses a stabilized preparation of purified alkaline phosphatase that had been derivatized and then lyophilized in the presence of mannitol or lactose. EPO Publication No. 0091258A2, discloses a method for stabilizing tumor necrosis factor (TNF) by storage or lyophilization of the purified protein in the presence of a stabilizing protein, such as human serum albumin, gelatin, human γ globulin, or salmon protamine sulfate. U.S. Pat. No. 4,451,569 discloses the use of pentoses, sugar alcohols and some disaccharides to stabilize the activity of purified glutathione peroxidase. The stabilized composition may be freeze-dried and then stored at temperatures below 20° C. EPO Publication No. 0448146A1 discusses stabilized, lyophilized gonadotropin preparations containing a dicarboxylic acid salt. The preparation can further contain a disaccharide such as sucrose or trehalose. Roser, Biopharm, 47-53 (September 1991) discusses preserving the biological activity of various biological molecules dried at ambient temperature using trehalose. PCT Publication No. W087/00196 reports the stabilization of monoclonal antibodies and calf intestine alkaline phosphatase by air drying in the presence of trehalose. PCT Publications W089/00012 and W089/06542 discuss the use of trehalose to preserve some foods and the antigenicity of live virus particles. EPO Publication 02270799A1 reports the stabilization of recombinant β-interferon in a formulation containing a stabilizing agent such as a detergent or glycerol. The compositions can further comprise various sugars including sucrose and trehalose, sugar alcohols, and proteins as additional stabilizing agents; most preferred among these is dextrose.
Some of these additives have been found to extend the shelf life of a biologically active material to many months or more when stored at ambient temperature in an essentially dehydrated form. However, the effectiveness, suitability or superiority of a particular prospective additive depends on the chemical composition of the biologically active material sought to be stabilized; in the case of a protein these factors may include, without limitation, the amino acid sequence of the protein, and its secondary, tertiary and quaternary structure. Thus, whether a particular composition will function to preserve biological activity for a particular biologically active material is not a priori predictable.
Moreover, if a protein is lyophilized, additional factors including, without limitation: the buffer composition, the speed of freezing, the amount of negative pressure, the initial, operating and final lyophilization temperatures and the length of the lyophilization procedure are important in determining the stability and shelf life of the active protein.
Some proteins are known to have multiple enzymatic activities. Thus, retroviral reverse transcriptase enzymes such as those derived from Moloney Murine Leukemia Virus (MMLV-RT) have a DNA-directed DNA polymerase activity, an RNA-directed DNA polymerase activity, and an RNAse H activity. While these activities are contained in the same enzyme, conditions for the preservation of any one of these activities in a dried preparation does not assure that one or both of the remaining enzyme activities will also be preserved under the same conditions.
Moreover, when a particular application requires that the balance of relative specific activities of the three activities of reverse transcriptase remain similar after reconstitution to the balance of these activities before drying, as in the transcription-based nucleic acid amplification system of Kacian & Fultz, supra (which enjoys common ownership with the present application and is incorporated by reference herein), a particular preservation method may upset the delicate balance of these enzymatic activities, thereby making the enzyme unsuitable for such use. Thus, if the RNaseH activity of the enzyme is preserved more than the RNA-directed DNA polymerase activity, the RNA:DNA initiation complex may be degraded before DNA synthesis can begin.
Since a given cryoprotectant composition effective for the long-term preservation of a given enzymatic activity is not clearly effective or superior when applied to another enzymatic activity, different enzymes often require quite different protestants for activity stabilization. As a result, among commercially manufactured lyophilized enzyme preparations, all or most contain only a single enzyme dried in a formulation customized to preserve the activity of that specific enzyme.
SUMMARY OF THE INVENTION
The present invention is directed to compositions and kits comprising dried formulations of reverse transcriptase and RNA polymerase able to be stored at ambient temperature for prolonged periods of time without substantial losses of enzymatic activities. Preferably, the formulations comprise preparations of retroviral reverse transcriptase and/or bacteriophage RNA polymerase. More preferably, the formulations comprise reverse transcriptase derived from Moloney Murine Leukemia Virus (MMLV-RT) and bacteriophage T7 RNA polymerase in a cryoprotectant excipient. Even more preferably, the invention is directed to single containers comprising dried formulations containing both MMLV-RT and T7 RNA polymerase in one or more cryoprotectant excipients. Most preferably, the invention is directed to single containers comprising dried formulations containing MMLV-RT and T7 RNA polymerase, one or more cryoprotectant excipients comprising either or both trehalose and polyvinylpyrrolidone (PVP), nucleotide triphosphates, and metal ions and co-factors necessary for said enzymatic activities wherein, upon reconstitution of the stabilized lyophilizate and addition of a target nucleic acid and one or more appropriate primers, the formulation is in a convenient and cost-effective form for nucleic acid amplification without the need for excessive handling. Optionally, such a formulation may contain primers for initiation of nucleic acid synthesis. Lastly, the present invention is directed to methods of making and using the dried formulations described above.
Reverse transcriptase and RNA polymerase enzymes are important agents in transcription-mediated nucleic acid amplification methods, such as those described in Burg et al., supra; Gingeras et al., supra, (sometimes called transcription amplification system or TAS); Kacian and Fultz, supra; Davey and Malek, EPO Application No. 8811394-8.9 and Malek et al., PCT Publication No. WO91/02818). Such methods are increasingly important in fields such as forensics and medical diagnostics, where the stability of the amplification reagents over time is an significant consideration in the cost of manufacturing, marketing and use of products which employ nucleic acid amplification.
Applicant has discovered a method and a dried formulation for the preservation of the DNA-directed DNA polymerase, RNA-directed DNA polymerase, and RNAse H activities of reverse transcriptase. The same method and formulation has been discovered to be suitable for the preservation of RNA polymerase activity. Moreover, Applicant has surprisingly found that both enzymes and all four enzymatic activities can be stabilized and preserved as a dried formulation in a single container without significant loss of any of the four activities over a substantial period of time, even after prolonged incubation at high temperature.
One aspect of the present method comprises providing an active purified reverse transcriptase with a cryoprotectant excipient comprising a non-reducing disaccharide (preferably sucrose or trehalose), or polyvinylpyrrolidone (PVP), or an amount of a mixture of these compounds effective to act as an agent protecting and preserving the DNA-directed DNA polymerase, RNA-directed DNA polymerase, and RNAse H activities of reverse transcriptase after drying the enzyme by methods such as, without limitation, lyophilization of a solution containing reverse transcriptase and the cryoprotectant.
In a second aspect, the invention features a method for stabilizing and preserving active purified RNA polymerase, preferably T7 RNA polymerase, in a dehydrated form substantially stable at room temperature for more than 90 days. In this aspect, the RNA polymerase is dried in the presence of metal salts, such as those containing Mg ++ or Zn ++ , one or more protective stabilizing agents selected from the group consisting of non-reducing disaccharides, preferably trehalose, and polyvinylpyrrolidone (PVP), and a reducing agent, such as n-acetyl-L-cysteine (NALC). While not wishing to be limited by theory, Applicant believes that the reducing agent helps to prevent inactivation of the enzyme through oxidation of any cysteine residues present in the enzyme. In this aspect, the RNA polymerase retains at least 70% of its original activity, preferably after exposure of the dehydrated formulation to a temperature of 45° C. for at least 30 days or 35° C. for at least 61 days.
In another aspect, the invention features a single dried formulation containing a mixture of reverse transcriptase (preferably MMLV-RT), RNA polymerase (preferably T7 RNA polymerase), an amount of a cryoprotectant excipient (preferably trehalose and/or polyvinylpyrrolidone) effective to preserve the enzymatic activities of the dried enzymes, nucleotide triphosphates, necessary co-factors, optional oligonucleotide primers, and a reducing agent, preferably a thiol compound.
In yet another aspect, the present invention comprises a component of a kit for the amplification and specific identification of nucleic acids belonging to one or more phylogenetic groupings of organisms, for example for the specific detection of one or more species within a genus or one or more genera within a family. The invention provides a reconstitutable dried formulation comprising a reverse transcriptase, an RNA polymerase, ribonucleotide triphosphates, deoxyribonucleotide triphosphates, zinc and/or magnesium salts, and a reducing agent in a single container. Amplification primers and an aqueous reconstitution solution may be supplied as one or more additional separate components of the kit. Alternatively, amplification primers may be comprised in the dried formulation. Target sequence-specific nucleic acid hybridization assay probes and any desired unlabeled helper oligonucleotides may be included in the dried formulation or provided in a separate reagent. Upon reconstitution of the dried formulation and addition of the oligonucleotide primers (if not already present), the mixture is contacted with a partially or wholly single-stranded target nucleic acid. If the target nucleic acid has nucleotide sequences complementary to the primer(s) (or the primer portion of a promoter-primer(s)), the reaction will proceed upon incubation of the reaction mixture at a temperature sufficient for nucleic acid amplification.
In another aspect, the invention comprises a single lyophilizate containing a combination of reverse transcriptase (preferably MMLV-RT), RNA polymerase (preferably T7 RNA polymerase), a cryoprotectant excipient, nucleotide triphosphates, necessary co-factors and a reducing agent, preferably containing a thiol group. The lyophilizate may be transported and stored without the need for refrigeration, and can withstand transient exposure to elevated temperatures, for example, without limitation, 55° C. for 30 days, without significant diminution of enzyme activity.
By "nucleotide triphosphates" is meant ribo- or deoxyribonucleotide triphosphates and derivatives thereof which are able to serve as substrates for an RNA polymerase and a DNA polymerase, preferably a reverse transcriptase, respectively. Such derivatives may include, without limitation, nucleotides having methyl (or other alkyl) and/or sulfur groups incorporated at the nitrogenous base (usually adenine, thymine or uracil, cytosine and guanine), the ribose or deoxyribose moiety, or the phosphate group.
By "nucleotide" is meant a nucleic acid subunit comprising a single nitrogenous base (usually adenine, thymine or uracil, cytosine and guanine), a sugar moiety (ribose or deoxyribose) and a phosphate group. As used herein, the term refers both to unincorporated ribo- or deoxyribonucleotide triphosphates and to the covalently-linked nucleotide subunits of an oligonucleotide or nucleic acid strand, depending upon the context of usage.
DETAILED DESCRIPTION OF THE INVENTION
The present invention involves methods for stabilizing the enzymatic activities of DNA polymerase and RNA polymerase enzymes by removing the solvent from a solution containing one or more of these enzymes in the presence or a cryoprotectant, or stabilizing "bulking agent". Such cryoprotectants include saccharides, particularly non-reducing disaccharides, and water soluble polymers having electropositive and/or electronegative groups available for hydrogen-bonding with the enzyme. Particularly preferred cryoprotectants are the disaccharides sucrose and trehalose and the polymer polyvinylpyrrolidone (PVP).
The present invention also relates to stabilized compositions comprising a desiccated DNA polymerase, a desiccated RNA polymerase, or a desiccated mixture containing both a DNA polymerase and an RNA polymerase. Preferred enzymes comprising these compositions are reverse transcriptases and bacteriophage RNA polymerases; particularly preferred enzymes are the retroviral reverse transcriptase from Moloney Murine Leukemia Virus and the RNA polymerase from bacteriophage T7.
A preferred method of desiccating the DNA polymerase and RNA polymerase of the present invention is by lyophilization. In this process, a solution containing the enzyme is frozen, a vacuum applied to the frozen enzyme solution, and the solvent removed from the preparation by sublimation, leaving behind the solutes.
The present invention also features a composition for the replication of one or more particular nucleic acid sequences which includes a desiccated preparation of a DNA polymerase (preferably a reverse transcriptase), an RNA polymerase, nucleotide triphosphates, and co-factors necessary for enzyme activity. The desiccated preparation may also contain amplification primers for the specific replication of the target nucleotide sequence and/or hybridization assay probes and helpers. Preferably, the desiccated composition is prepared by lyophilization.
The compositions of the present invention are stable for a prolonged period, even when stored at high temperatures. Such compositions are thus useful in shipping and storage of commercial preparations of these enzymes and of kits for nucleic acid amplification which contain these enzymes.
EXAMPLES
It will be understood that the following examples are intended to illustrate various presently preferred embodiments of the present invention and do not in any way limit its scope. Nor is the disclosure of an embodiment a representation that other embodiments of the invention might not exist which are more effective to achieve one or more object sought to be addressed by the present invention.
Example 1
Lyophilization of Reverse Transcriptase and RNA Polymerase
The reverse transcriptase used in this and the following examples was either a recombinant Moloney Murine Leukemia Virus reverse transcriptase expressed in E. coli strain 1200 and purified from a cell paste or a commercially available, purified MMLV-RT preparation obtained from United States Biochemicals, Cleveland, Ohio. The enzyme preparation was stored at -20° C. in a storage buffer containing 20-50 mM Tris-HCl (pH 7.5), 0.1M NaCl, 0.1 mM ethylenediamine tetraacetic acid (EDTA), 1.0 mM dithiothreitol (DTT), 0.01% (v/v) TERGITOL NP®-40 (TERGITOL NP® is a registered trademark of Union Carbide Chemicals and Plastics Co., Inc.) or 0.1% (v/v) TRITON® X-100 (TRITON® is a registered trademark of Union Carbide Chemicals and Plastics Co., Inc.), and 50% (v/v) glycerol. Purified T7 RNA polymerase was obtained from Epicentre Technologies, Madison, Wis. Prior to dialysis the enzyme was stored in 50% (v/v) glycerol, 50 mM Tris-HCl (pH 7.5), 0.1M NaCl, 1.0 mM DTT, 0.1 mM EDTA and 0.1% (v/v) TRITON® X-100. This enzyme was also stored at -20° C. prior to dialysis.
Three enzyme preparations were dialyzed in preparation for lyophilization. The first preparation contained 324,012 units of MMLV-RT diluted into a buffer containing 20 mM HEPES ([2-hydroxyethyl]piperazine-N'-[2-ethanesulfonic acid])(pH 7.5), 0.1M NaCl, 0.1 mM EDTA, 2 mM NALC, 0.1 mM zinc sulfate, 0.2M trehalose and water. The final volume was 720 μl. This was dialyzed against 250 ml of the same buffer (Trehalose Buffer) for 6 hours at 4° C. The dialysis membranes were prepared by boiling in 2% (w/v) sodium bicarbonate and 10 mM EDTA (pH 8.0), then in 10 mM EDTA (pH 8.0), and finally in deionized water for 10 minutes each time. The membranes were then thoroughly rinsed with deionized water prior to use. The dialysis buffer was changed with the same volume of fresh buffer and dialysis continued for an additional 10 hours. Buffer was changed again and continued for another 3 hours. The final volume was 655 μl.
The second preparation contained 144,000 units of T7 RNA polymerase in 720 μl. This was dialyzed against Trehalose Buffer on the same schedule and in the same volumes as the reverse transcriptase preparation. Final volume was 1270 μ.
The third preparation contained both reverse transcriptase and RNA polymerase; 324,012 units of reverse transcriptase and 144,000 units of RNA polymerase were combined to a final volume of 1440 μl. This was dialyzed against 3 equal volumes of Trehalose Buffer on the same schedule as the other two preparations. The final volume of the dialysate was 1975 μ.
After dialysis, each preparation was divided into 12 equal aliquots in vials. Each vial contained 27,000 units of reverse transcriptase, 12,000 units of T7 RNA polymerase, or both enzymes in these amounts. The vials were placed in a programmable Virtis model lyophilizer 101-SRC with a FCP-III control system. The vials were cooled to -40° C. in approximately 5 minutes. Lyophilization was commenced by decreasing the pressure to -180 Torr; the vacuum was kept constant throughout the lyophilization protocol. The temperature was then raised in a linear fashion to -10° C. during the following 2 hours and maintained at this temperature for the next 6 hours. The temperature was then linearly raised to 10° C. over the next hour, and maintained at 10° C. for 4 hours. The temperature was again linearly ramped up to 25° C. over the next 30 minutes and maintained at 25° C. for the following 10.5 hours. The pressure was then returned to atmospheric with the introduction of dry nitrogen, and the vials were sealed under nitrogen before their removal from the lyophilizer. The vials were then stored at 25° C. for 22 days.
After the storage period, the lyophilized enzyme preparations were reconstituted in Reconstitution Buffer (0.01% (v/v) TRITON® X-100, 41.6 mM MgCl 2 , 1 mM ZnC 2 H 3 O 2 , 10% (v/v) glycerol, 0.3% (v/v) ethanol, 0.02% (w/v) methyl paraben, and 0.01% (w/v) propyl paraben) and assayed for their ability to support nucleic acid amplification.
Reaction mixtures of 90 μl total volume were prepared containing 50 mM Tris-HCl (pH 8.0), 17.5 mM, 2 mM spermidine, 25 mM KCl, 2 mM each of dATP, dCTP, dTTP and dGTP, 2.5 mM CTP and UTP, 6.5 mM ATP and GTP, 5 mM DTT, 0.44 μl of a 675 μg per ml solution of a promoter-primer (SEQ ID NO: 1) having a target binding region complementary to a region of one strand of bacteriophage T7 Gene 10, 0.3 μl of a 451 μg per ml solution of a primer (SEQ ID NO: 2) having a target binding region complementary to the other strand of bacteriophage T7 Gene 10, one hundred copies of the T7 Gene 10 target nucleic acid and water. The T7 Gene 10 RNA target was a (+) sense transcript of a plasmid-borne T7 Gene 10 restriction fragment derived from plasmid pGEMEX-1 (Promega Corporation, Madison, Wis.). The purified RNA transcript was present at a concentration of 0.61 picomoles/μl. One hundred copies of the target nucleic acid were added to each tube. Each tube was also overlayed with 200 μl of mineral oil to prevent evaporation of the sample during the assay.
All tubes were incubated at 95° C. for 5 minutes and allowed to cool to room temperature before the addition of enzyme reconstituted as described above; while this step is not necessary when the target nucleic acid is RNA or single-stranded DNA rather than double-stranded DNA, an initial heat step helps to melt any regions of RNA intramolecular hydrogen-bonding. The experimental tubes containing the separately lyophilized enzyme preparations were then given 10 μl of a solution containing 400 units of T7 RNA polymerase and either 600 or 900 units of lyophilized MMLV-RT; the co-lyophilized T7 RNA polymerase and MMLV-RT were present at concentrations of 400 units and 900 units per 10 μl, respectively. The tubes were incubated at 37° C. for 3 hours.
The amount of amplified nucleic acid produced during the reaction was determined using the homogeneous protection assay described in Arnold and Nelson, U.S. Pat. No. 5,283,174 (which enjoys common ownership with the present application and which is incorporated by reference herein); it will be clear to one of skill in the art that many other assay systems and methods of detecting a nucleic acid target, such as by employing radiolabeled probes, are available in the art.
The amplification reaction was terminated with the addition to each tube of 100 μl of a hybridization buffer containing 200 mM lithium succinate (pH 5.2), 17% (w/v) lithium lauryl sulfate, 3 mM EDTA (ethylenediamine tetraacetic acid) and 3 mM EGTA ([ethylenebis(oxyethylenitrilo)]-tetraacetic acid)) and an acridinium ester-labeled probe (SEQ ID NO: 3) complementary to the T7 Gene 10 RNA transcript. The tubes were incubated at 60° C. for 20 minutes. The acridinium ester associated with unhybridized probe was hydrolyzed with the addition of 300 μl of 182 mM NaOH, 600 mM boric acid and 1% (v/v) TRITON® X-100 and the tubes incubated at 60° C. for 5 minutes. The remaining chemiluminescence was measured in a luminometer upon the addition of 200 μl of 1% (v/v) H 2 O 2 in 0.4 N HNO 3 followed immediately with alkalination of the solution with the immediate addition of (200 ul) 1M NaOH. The results are reported in relative light units (RLU), which is a measure of the number of photons emitted by the chemiluminescent label. Results are shown in Table 1 below.
TABLE 1__________________________________________________________________________Comparison of Lyophilized Enzymes Stored at 25° C. for 22 dayswithUnlyophilized Enzymes RNA Target Negative Control 600 units 900 Units 600 units 900 Units MMLV-RT and MMLV-RT and MMLV-RT and MMLV-RT and 400 units of 400 units of 400 units of 400 units of T7 polymerase T7 polymerase T7 polymerase T7 polymerase__________________________________________________________________________Liquid MMLV-RT 321329 428872 1868 5630and Liquid T7RNA polymeraseLyophilized 301253 463561 1681 1684MMLV-RT andLiquid T7 RNApolymeraseLiquid MMLV-RT 549204 343582 1366 1545and LyophilizedT7 RNApolymeraseLyophilized 415080 493779 1352 1374MMLV-RT andLyophilized T7RNA polymerase(SeparatelyLyophilized)Co-Lyophilized 677531 654359 1376 1296MMLV-RT and T7 (900 units (900 unitsRNA polymerase MMLV-RT) MMLV-RT)__________________________________________________________________________
These results indicate that the co-lyophilized MMLV-RT and T7 RNA polymerase caused amplification of the RNA Gene target more effectively than in reaction mixtures with either enzyme preparation paired with a liquid enzyme preparation of the other enzyme, or where both enzymes were unlyophilized. The was no significant diminution in the ability of any of the lyophilized enzyme preparations to catalyze amplification as compared to the liquid enzymes. Thus, the results also demonstrate that each enzyme can be effectively stabilized by storage in a dried state in the presence of trehalose, either alone or together. Because nucleic acid amplification under these conditions depends on the presence of all three of the enzymatic activities of reverse transcriptase (RNA-directed DNA polymerase, DNA-directed DNA polymerase and RNAse H), the assay is an effective indication both that these activities are effectively stabilized by the present method and that the activities remain coordinated in such a way as to promote nucleic acid amplification.
Additional experiments showed that reverse transcriptase can be lyophilized in the presence of sucrose rather than trehalose under similar conditions; trehalose appeared to be slightly superior to sucrose as a cryoprotectant stabilizing agent. (See Example 6.)
b. Lyophilization Of Reverse Transcriptase and T7 RNA Polymerase in the presence of Non-Ionic Detergent
Reverse transcriptase and RNA polymerase were co-dialyzed and lyophilized in the presence of a non-ionic detergent in order to attempt to minimize precipitation of protein during the lyophilization procedure while maintaining the enzymatic activity dialysis of the enzymes. Six dialysis mixtures were prepared containing 0%, 0.01%, 0.05%, 0.1%, 0.2%, and 0.5% TRITON® X-102 in a dialysis buffer. The dialysis buffer contained 20 mM HEPES, 0.1M NaCl, 0.1 mM EDTA, 5 mM NALC, 0.1 mM zinc acetate and 0.2M trehalose. Final volume of each dialysis mixture was 250 ml. Four hundred sixty seven microliters of each buffer was combined with 46 μl MMLV-RT (2900 units/μl) and 74 μl T7 RNA polymerage (800 units/μl) for a starting volume for each dialysate of 587 μl. The samples were dialyzed against 60 ml of the corresponding buffer at 4° C. with three changes of the same volume of buffer. Following the third buffer change, a precipitate was seen in the samples containing 0%, 0.01% and 0.05% TRITON® X-102; no such precipitate was seen in the samples containing 0.1%, 0.2% or 0.5% TRITON® X-102.
After dialysis, the volume of each dialysate was measured and the calculated enzyme concentrations adjusted accordingly. Each sample was divided into 4 vials, with each vial containing 24,750 units of MMLV-RT and 11,000 units of T7 RNA polymerage. Lyophilization was performed as above. The appearance of the detergent-containing lyophilizates after drying was indistinguishable from lyophilizates prepared in the absence of TRITON® X-102. Following lyophilization, the vials were stored at 4° C. and 55° C. for 32 days.
The effect of the non-ionic detergent on the activity of the enzymes was assessed in an amplification assay using the T7 Gene 10 amplification system. Each lyophilized enzyme preparation was rehydrated in Reconstitution Buffer; 900 units of MMLV-RT and 400 units of T7 RNA polymerage were assayed in each reaction mixture. RNA Gene 10 transcripts (100 copies per reaction) were used as the target nucleic acid. The assay was conducted as described above unless expressly indicated otherwise. Results are reported in RLU.
TABLE 2______________________________________Stability of Lyophilized Enzymes Upon 32 Days' Storagein the Presence of DetergentStored at 4° C. Stored at 55° C.Sam- RNA target No RNA Target Nople* (Duplicates) Target (Duplicates) Target______________________________________A 1612901 1317601 1543B 1151828 1146113 1700 791757 320417 1701C 1286845 1219888 1544 1190527 905066 1690D 1215264 1205790 1513 1251635 1388493 1513E 1208586 1418260 1545 1245880 1052251 1591______________________________________ *Sample A = Unlyophilized enzymes stored at -20° C. Sample B = Lyophilized enzymes in 0% TRITON ® X102. Sample C = Lyophilized enzymes in 0.1% TRITON ® X102. Sample D = Lyophilized enzymes in 0.2% TRITON ® X102. Sample E = Lyophilized enzymes in 0.5% TRITON ® X102.
These results demonstrate that a non-ionic detergent such as TRITON® X-102 can effectively prevent the formation of a protein precipitate after dialysis of MMLV-RT or T7 RNA polymerase. The results also show that TRITON® X-102 dos not have a deleterious effect upon amplification of the target nucleic acid, and may even act to better stabilize the enzyme activities when the lyophilized enzymes are stored at elevated temperatures over time. The detergent does not cause an increase in the background luminescence in this assay. These results also demonstrate that even the sample lyophilized in the absence of detergent (Sample B) remains approximately as active as non-lyophilized enzymes. The results indicate further that when the lyophilized enzyme preparation is stored at elevated temperature for a prolonged period of time the lyophilized enzyme preparation does not experience detectable diminution in activity.
It will be clear to one of skill in the art that these results immediately suggest that other non-ionic detergents such as, without limitation, detergents of the BRIJ series, the TWEEN series, other detergents of the TRITON series, and the TERGITOL series may be easily screened as indicated above for their ability to maintain the dried proteins in a soluble state during lyophilization without having an adverse effect on enzyme activity.
Example 2
Co-Lyophilization of Reverse Transcriptase and RNA Polymerase with Amplification Reagents
Moloney Murine Leukemia Virus reverse transcriptase and T7 RNA polymerase enzyme preparations were kept at -20° C. in a storage buffer containing 50 mM Tris-HCl (pH 7.5), 0.1M NaCl, 0.1 mM EDTA, 1 mM DTT, 0.01% (v/v) NP®-40 or 0.1% (v/v) TRITON® X-100 and 50% (v/v) glycerol prior to drying.
In preparation for lyophilization, 3×10 6 units of MMLV RT and 1.3×10 6 units of T7 polymerase (2.5 ml of each preparation) were combined and dialyzed against at least 50 volumes of a buffer containing 20 mM HEPES (pH 7.5), 5 mM NALC, 0.1 mM EDTA, 0.1 mM zinc acetate, 0.2% (v/v) TRITON® X-102, and 0.2M trehalose using dialysis membranes with a molecular weight cutoff of 12,000 Daltons at 2°-8° C. with three changes of the same volume of buffer for at least 8 hours between each buffer change.
Twenty milliliters of the dialyzed enzyme preparation was combined with 60 ml of an Amplification Reagent containing 10.0 mM spermidine, 250 mM imidazole/150 mM glutamic acid (pH 6.8), 99 mM NALC, 12.5% (w/v) PVP, 12.5 mM each of rCTP and rUTP, 31.2 mM each of rATP and rGTP, and 10.0 mM each of dCTP, dGTP, dATP and dTTP (6:2 volume ratio). Additional experiments have shown that the reagents may be combined in a 7:1 volume ratio (Amplification Reagent to enzyme preparation) without significantly different results. Theoretically, the dialyzed enzyme preparation and the Amplification Reagent may be combined in equal proportions; determination of an appropriate ratio of Amplification Reagent to enzyme is well within the ability of the skilled artisan.
The final composition of the combined enzyme:Amplification Reagent formulation prior to lyophilization was: 2.7×10 6 units of MMLVRT and 1.2×10 6 of T7 polymerase 6×10 6 units of each enzyme, 5.0 mM HEPES (pH 6.8 to 7.0), 0.025 mM EDTA, 0.025 mM zinc acetate, 10.0 mM spermidine, 187.5 mM imidazole, 112.5 mM glutamic acid, 75.6 mM NALC, 0.05% (v/v) TRITON®X-102, 9.4% (w/v) PAP (average MW 40,000 Daltons), 0.05 M trehalose, 9.4 mM each of rCTP and rUTP, 23.4 mM each of rATP and rGTP, and 7.5 mM each of dCTP, dGTP, dATP and dTTP.
Eight hundred microliters of the combined enzyme:Amplification Reagent preparation (hereafter Enzyme:Amplification Reagent) Were placed into each individual glass vial for lyophilization (approximately 39,000 units of total enzymes per vial). Lyophilization was conducted as follows in Example 1. After lyophilization, the vials were then treated as indicated in the following examples.
Example 3
Amplification Activity Assay of Lyophilized Reagent
Freshly lyophilized preparations of reverse transcriptase, RNA polymerase, and Amplification Reagent were incubated at 25° C., 35° C. and 45° C. for various times, ranging from 3 to 61 days. All vials were prepared identically from the same preparation. At the indicated time points vials containing the lyophilized reagents were removed from elevated temperature and stored at -30° C. until the last samples had been collected. Samples representing the "zero" time for each temperature were stored at -30° C. for the entire experimental time period.
When the vials from the last time point had been collected all samples were rehydrated in 1.5 ml of Reconstituting Reagent (0.01% (v/v) TRITON® X-102, 41.6 mM MgCl 2 , 1 mM ZnC 2 H 3 O 2 , 10% (v/v) glycerol, 0.3% (v/v) ethanol, 0.02% (w/v) methyl paraben, and 0.01% (w/v) propyl paraben) and the contents of each vial assayed for the ability to cause nucleic acid amplification.
Activity in a model amplification system was measured in the following way in this example. Each amplification reaction mixture contained 500 copies of a double-stranded DNA restriction fragment from a plasmid containing part of the hepatitis B virus genome as the target nucleic acid (a PUC plasmid containing a 2.6 kb fragment of the hepatitis B virus genome). The target DNA was diluted in 20 μl of either water or human serum. Negative controls were made in the same way, but without target DNA. This was added to 20 μl of a 2X primer solution; the final composition of this solution was 0.1N KOH, 17.5 mM EGTA, 25 mM imidazole, 25 mM glutamic acid, 0.025% (w/v) phenol red, and 0.3 μM of each of two primers in a total volume of 40 μl. The first primer ((-) sense) consisted of a 3' target-binding nucleotide sequence region complementary to the (+) sense strand of the DNA target and a 5' non-complementary region was situated downstream from a 5' non-complementary region having the nucleotide sequence of the promoter for T7 RNA polymerase. The second primer ((+) sense) had a nucleotide sequence consisting of a target-binding region complementary to the other ((-) sense) DNA strand.
Each 40 μl reaction mixture was incubated at about 95° C. to denature the double-stranded DNA target. The reaction was then cooled to room temperature for 5 minutes and neutralized with 10 μl of a buffer containing 330 mM imidazole and 200 mM glutamic acid. Had the target nucleic acid been RNA rather than DNA this denaturation step would not be necessary.
Fifty microliters of each reconstituted Enzyme:
Amplification Reagent was given to 50 μl of the denatured, neutralized DNA reaction mixture, which was then incubated at 37° C. for 3 hours. Each reaction was terminated by the addition of 20 μl (40 units) of RNAse-free DNAse I.
The relative amplification of each reconstituted Enzyme:Amplification Reagent was determined by using the homogeneous protection assay (HPA) described in Arnold & Nelson, U.S. Pat. No. 5,283,174; it will be understood by those of skill in the art that other assay methods employing different detection means, such as radioactive labels, may be used. Each amplification reaction was given 100 μl of a solution of 10 mM lithium succinate (pH 5.0), 2% (w/v) lithium lauryl sulfate, 1 mM mercaptoethanesulfonic acid, 0.3% (w/v) PVP-40, 230 mM LiOH, 1.2 M LiCl, 20 mM EGTA, 20 mM EDTA, 100 mM succinic acid (pH 4.7) and 15 mM 2,2'-dipyridyl disulfide containing approximately 75 femtomoles (fmol) of an acridinium ester-labeled oligonucleotide probe ((+) sense) designed to be complementary to the amplified RNA amplicons. Each tube was mixed, incubated at 60° C. for 20 minutes, and then allowed to cool. Each reaction mixture was given 300 μl of a solution containing 0.6M sodium borate (pH 8.5), 1% (v/v) TRITON® X-100 and 182 mM NaOH and incubated for 6 minutes at 60° C. to destroy label unassociated with hybridized probe.
The reaction mixtures were cooled for 5 minutes, and the remaining chemiluminescence was measured in a 30200 luminometer (LEADER®Gen-Probe Incorporated, San Diego, Calif.) after an automatic injection of 200 μl 0.1% (v/v) H 2 O 2 , 0.1 mM nitric acid, followed immediately by an injection of 1.0N NaOH. The amount of subsequently emitted light is reported in Relative Light Units (RLU). Under these conditions the background level of light emission was in the range of about 2000 to 4000 RLU.
The results were recorded and tabulated for each temperature of storage (25° C., 35° C. and 45° C.) as indicated below. Each sample was assayed in triplicate and averaged. This average was used to plot the data for each temperature graphically.
TABLE 3__________________________________________________________________________Stability of Lyophilized Enzyme:Amplification ReagentStorage Temperature 25° C. Days of Storage 0 11 16 20 30 40 61__________________________________________________________________________Reagents 2053 1911 1524 2188 1851 1548 1972without DNA 2130 1590 1561 1990 1847 1726 1655Target 2148 1752 2037 1606 1923 2382 1538(RLU)Average RLU 2110 1751 1707 1928 1874 1885 1722Reagents 1562029 2105440 1248988 2129935 1927067 1417883 1486111with DNA 1756224 1903081 1509929 2363198 1422699 1601071 1290950Target 1070164 1492458 1944566 1922529 1274124 1889588 1210344(RLU)Average RLU 1462806 1833659 1567828 2138554 1541297 1636181 1329135Reagents in 8437 2904 2660 3044 2919 2465 2946Human 3902 2893 2993 3152 2971 3089 3473Serum, No 3534 3003 2768 2951 2379 2958 3686DNA Target(RLU)Average RLU 5291 2933 2807 3049 2756 2837 3368Reagents in 1955525 2282336 2282171 1760428 2034705 1936366 1643624Human 2255411 2204415 1860043 1992765 2101999 1770109 1762360Serum, with 2282281 2206778 1903519 2093235 2064041 1811820 1622750DNA Target(RLU)Average RLU 2164406 2231176 2015244 1948809 2066915 1839432 1676245__________________________________________________________________________
TABLE 4__________________________________________________________________________Stability of Lyophilized Enzyme/Amplification ReagentStorage Temperature 35° C. Days of Storage 0 3 9 16 21 50 61__________________________________________________________________________Reagents 2429 17989 1768 1878 2378 1430 1559without DNA 2203 1775 1649 1919 2330 1411 1566Target 1996 1891 1840 2043 1995 1338 1692(RLU)Average RLU 2209 7218 1752 1947 2234 1393 1606Reagents 1173260 2310573 2186899 1559681 1876363 1458120 1366068with DNA 1580018 2136598 2119044 1385165 1919833 1932847 1443874Target 1389614 2303010 1568334 1632416 1979406 1343433 1421081(RLU)Average RLU 1380964 2251060 1958092 1525754 1925201 1578133 1410341Reagents in 4819 3298 3608 3575 2912 3074 3836Human 4779 9577 3200 3535 3422 3044 4160Serum, No 24541 3349 3114 3712 3151 3027 3901DNA Target(RLU)Average RLU 11380 5408 3307 3607 3162 3048 3966Reagents in 1946881 2228745 2233566 2087936 1984355 2255784 1873070Human 2158003 2289829 2303812 2163922 2192597 2147927 1789954Serum, with 2110796 2286956 2179206 2152655 2121658 2087549 2049762DNA Target(RLU)Average RLU 2071893 2268510 2238861 2134838 2099537 2163753 1904262__________________________________________________________________________
TABLE 5______________________________________Stability of Lyophilized Enzyme/Amplification ReagentStorage Temperature 45° C.Days of Storage0 6 11 16 33______________________________________Reagents 2508 1613 1687 2626 1594without 2250 1872 1781 2027 1596DNA Tar- 2159 1903 2206 2056 1661get (RLU)Average 2306 1796 1891 2236 1617RLUReagents 1431296 1097084 975001 1320113 1017853with DNA 1329706 949892 758705 939417 1368153Target 1288191 798877 1242188 972442 1015174(RLU)Average 1349731 948618 991965 1077324 1133727RLUReagents in 3554 3375 3011 3068 3183Human 3109 4452 3119 3559 3115Serum, No 4239 2960 3382 3381 2826DNA Tar-get (RLU)Average 3634 3596 3171 3336 3041RLUReagents in 1663770 1850263 1691590 1691372 1615426Human 1677985 1868747 1684565 1709387 1913706Serum, 1747637 2016609 1646303 1765393 1799445with DNATarget(RLU)Average 1696464 1911873 1674153 1722051 1776192RLU______________________________________
These data show that the co-lyophilized Enzyme:Amplification Reagent prepared in accordance with the method herein described retains all four of the enzymatic activities (RNA-directed DNA polymerase, DNA-directed DNA polymerase, RNAse H, and RNA polymerase) necessary to achieve nucleic acid amplification according to the transcription-mediated amplification method employed. Additionally, the data indicate that there is no noticeable deleterious effect on the nucleotide triphosphates or any other component of the Amplification Reagent when the reagent is co-lyophilized with reverse transcriptase and RNA polymerase.
These results also show that the enzymatic activities of reverse transcriptase and RNA polymerase enzymatic activities are not significantly inhibited when the amplification reaction is performed in the presence of a complex biological sample, such as human serum. Hence, the lyophilized amplification reagent appears to be suitable for use in conjunction with samples such as those obtained in clinical diagnostic settings.
The data can be interpreted in a number of ways; one of the more useful means of interpretation utilizes a form of the Arrhenius equation to predict the stability of the composition over an even greater time than actually tested. The Arrhenius equation is commonly used by those of skill in the art to predict the rates of chemical reactions and the stability of various thermolabile compounds as a function of temperature.
As utilized herein, the Arrhenius equation assumes a first order reaction of enzyme (or reagent) inactivation wherein an active enzyme or reagent has a single rate of inactivation at a given temperature and a single mechanism of inactivation at all tested temperatures. The equation utilized by the Applicant is:
ln(k.sub.2 /k.sub.1)=(-E.sub.a /R)((T.sub.2 -T.sub.1)/(T.sub.2 ×T.sub.1))
where k 2 equals the rate constant at the experimental temperature (°K.), k 1 equals the rate constant for the reaction at a reference temperature, E a equals the activation energy of the reaction, R equals the gas constant (1.987 cal/°K.-mole), T 1 equals the reference temperature (e.g., 298.16° K. (25° C.)), and T 2 equals the experimental temperature (expressed in °K.).
If E a is assumed to be 15,000 cal/mole and the reference and experimental temperatures are known, then a ratio of the rate constants k 2 /k 1 can be determined. In the simple case where both the reference and experimental temperatures are 25° C., the ratio of these constants is 1 since the constants are identical. If the experimental temperature is 35° C. and the reference temperature is 25° C., the predicted ratio will be 2.27. If the experimental temperature is 45° C. and the reference temperature is 25° C., the predicted ratio will be 4.91. Using the same equation, if the reference temperature is 5° C. and the experimental temperature is 45° C., the ratio is 30.33.
The rate constant ratios can be considered the "decomposition ratio" of the experimental storage time to the normal storage time, whether this time is expressed in hours, days, weeks, etc. Therefore, if the lyophilized enzyme/amplification reagent decomposes to 90% of its original potency in 30 days at 45° C., the Arrhenius equation predicts that it would take 147.3 (30×4.91) days at 25° C. for the activity to be similarly reduced.
Thus, the data demonstrate that the combined components of the lyophilized preparation do not noticeably lose their ability to support amplification in "real time", even after 30 days at 45° C. Moreover, by utilizing the Arrhenius equation the same data predict that the reagents would not suffer a significant loss in activity if the lyophilized reagent was actually stored for almost 5 months at 25° C. or for 2.5 years (30.33×30 days) at 5° C. prior to use.
The Applicant presents these methods of data analysis as an aid to the understanding of the present invention, and does not wish to be limited or bound by theoretical considerations. The actual stability of the compositions of the present invention may vary from the predictions of the Arrhenius equation, which provides general guidance toward predicting the stability of the lyophilized reagents.
Example 4
T7 RNA Polymerase Assay of Lyophilized Reagent
The lyophilized Enzyme:Amplification Reagent prepared in Example 2 was incubated at 35° C. for 0, 3, 9, 16, 21 and 30 days. At each of these time points vials were removed from the stress temperature and stored at -30° C. until the last samples had been collected.
RNA polymerase activity was measured by reconstituting each aliquot of lyophilized reagent in 1.5 ml of Reconstituting Buffer (0.01% (v/v) TRITON® X-100, 41.6 mM MgCl 2 , 1 mM ZnC 2 H 3 O 2 , 10% (v/v) glycerol, 0.3% (v/v) ethanol, 0.02% (w/v) methyl paraben, and 0.01% (w/v) propyl paraben). The reagent was then diluted 100-fold, 200-fold and 400-fold in a solution containing 20 mM HEPES (pH 7.5), 5 mM NALC, 0.1 mM EDTA, 0.1 mM ZnC 2 H 3 O 2 , 0.1 M NaCl and 0.2% (v/v) TRITON® X-102. A reaction pre-mix was made up separately, containing 22 mM MgCl 2 , 7.8 mM each of ATP and GTP, 2.5 mM each of CTP and UTP, 62.5 mM Tris (pH 7.5), 2.5 mM spermidine and 0.5 nanomoles of a target nucleic acid. The target was a linearized pUC T7G10 plasmid having a T7 promoter positioned immediately upstream from bacteriophage T7 Gene 10. This plasmid was derived from plasmid pGEMEX-1 (Promega Corporation, Madison, Wis.).
The reaction pre-mix was divided into 40 μl aliquots, and each aliquot was incubated for 3 minutes at 37° C. Ten microliters of each dilution of the Enzyme:Amplification Reagent was added to the warmed pre-mix tubes and incubated for 20 minutes at 37° C. Fifty microliters of a solution of 10 mM lithium succinate, 2% (w/v) lithium lauryl sulfate, 1 mM mercaptoethanesulfonic acid, 0.3% (w/v) PVP-40, 230 mM LiOH, 1.2M LiCl, 20 mM EGTA, 20 mM EDTA, 100 mM succinic acid (pH 4.7) and 15 mM 2.2'-dipyridyl disulfide containing approximately 75 femtomoles of an acridinium ester labeled Gene 10 oligonucleotide probe ((-) sense) designed to be complementary to the transcriptional products was added to each tube. A standard sample containing 10 femtomoles (fmol) of single-stranded DNA complementary to the Gene 10 probe was included in the HPA step to quantitate the amount of RNA produced in the experimental reaction mixtures. Hybridization was performed essentially as in Example 2, except that the hybridization volumes were half as large. Following degradation of the unhybridized label, the remaining acridinium ester was reacted and the emitted light measured in a luminometer as RLU.
The raw data was converted to units of RNA polymerase activity per μl as follows. The raw RLU obtained for the positive control reaction was subtracted from the RLU obtained in the negative control (no target DNA). This figure represents the net amount of emitted light obtained when 10 fmol of RNA are in the sample, and can be expressed as RLU/fmol RNA. Likewise, the RLU obtained for each sample can be subtracted from the background luminescence (RLU per 20 minutes). When this figure is divided by the figure obtained for the standard (RLU per fmol RNA) the result is the number of fmol RNA produced in each reaction per 20 minutes. Because 1 unit RNA polymerase activity was defined as the production of 1 fmol RNA in 20 minutes under the assay conditions, this figure is also the number of units of RNA polymerase activity in each 10 μl volume of enzyme originally added.
The data obtained from these reactions were first plotted for each time of storage at 35° C. by expressing fmol of RNA produced as a function of the number of microliters of the original 1.5 ml reconstituted Enzyme:Amplification Reagent represented in each experimental tube. A simple linear function was described. When the data had been plotted, a best-fit line for the data obtained for each time point was calculated; the slope of this curve was expressed as units of T7 polymerase activity per microliter. When the "zero time" time point is considered as 100% activity, the calculated units of T7 RNA polymerase for each remaining time point was expressed as percent activity remaining.
The results indicate that little if any decrease in T7 RNA polymerase occurs over the 30 day 35° C. incubation period.
Example 5
Reverse Transcriptase Assay of the Lyophilized Reagent
The activity of lyophilized MMLV reverse transcriptase incubated for 3, 9, 16, 21 and 30 days at 35° C. was assayed as follows. Individual vials were removed from the stress temperature at the indicated times and stored at -30° C. until the last samples had been collected.
Each vial was reconstituted in 1.5 ml reconstitution buffer and diluted 100 fold, 200-fold, and 400-fold as in Example 4. A separate reverse transcriptase pre-mix mixture was made containing 5 mM MgCl 2 , 30 mM KCl, 0.25 mM each of dATP, dTTP, dCTP, and dGTP, 62.5 mM Tris (pH 7.5), 2.5 mM spermidine, 3.75 nM target RNA, and 750 nM of an amplification primer. The target RNA was the T7 Gene 10 RNA transcripts generated in Example 4. The primer was an oligonucleotide 22 bases in length designed to hybridize to a region near the 3' end of the target RNA. Ten microliters of the enzyme dilutions were each added to 40 μl of the reaction pre-mix on ice. The reactions were conducted by incubation at 37° C. for 15 minutes. Each reaction was terminated with the addition of 50 μl of an acridinium ester-labeled hybridization probe. The probe was designed to be complementary to the newly synthesized Gene 10 cDNA.
Detection by HPA was conducted as described in Example 3. Results were measured in RLU.
This assay measured the RNA-directed DNA polymerase activity and the RNAse H activity of the MMLV reverse transcriptase. The latter activity is indirectly measured, since without degradation of the RNA strand of the RNA:DNA hybrid produced by extension of the Gene 10 primer, the probe would not be able to hybridize to the cDNA.
One unit of these combined enzymatic activities was defined as the detection of 1 fmol cDNA in 15 minutes under the reaction conditions described above. Calculation of the units of enzyme activity remaining at each time point and dilution was performed as in Example 4 using 10 fmol of the amplified cDNA as a standard.
The results indicate that little if any decrease in RT activity occurs over the 30 day 35° C. incubation period.
Example 6
Co-Lyophilization of Reverse Transcriptase and RNA Polymerase with Nucleotides and Primers
The preceding examples have illustrated the preparation and use of a single reagent containing a desiccated preparation of RNA polymerase and reverse transcriptase together with nucleotide triphosphates and co-factors necessary for nucleic acid amplification. It will be clear to one of skill in the art that, given the ability of such a "single vial" reagent to amplify nucleic acids after prolonged storage at raised temperatures, it should easily be possible to include the amplification primer(s) in the lyophilized preparation so as to reduce the number of steps in methods of using such a reagent, and to reduce the number of containers in a kit for nucleic acid amplification from three (for example, lyophilized Enzyme:Amplification Reagent, primers and Reconstitution Reagent) to two (for example, lyophilized Enzyme/primer/Amplification Reagent and Reconstitution Reagent).
Such a preparation is useful when the amplification reaction does not make use of temperatures which will denature one or both of the enzymes, such as when the initial target nucleic acid is RNA and the amplification method is an isothermal one, for example as in Kacian & Fultz, PCT Publication No. WO91/01384 or Kacian et al., PCT Publication No. W093/22461.
Example 7
Lyophilization of Reverse Transcriptase with Sucrose
Applicant has also discovered that sucrose, (for example, at a concentration of 0.2M), can be used as a cryoprotectant stabilizing agent in the lyophilization of reverse transcriptase; the stabilizing effect of sucrose appears to be good; compared to a standard liquid solution containing MMLV-RT and stored for the same period of time in 50% (v\v) glycerol at -20° C. the preparation lyophilized in 0.2M sucrose maintained 93% of the activity of the standard MMLV-RT preparation following storage of the lyophilizate for 30 days at 4° C. A similarly treated lyophilizate containing 0.2M trehalose rather than sucrose showed an average of 105% of the activity of the standard under the same conditions.
Example 8
Lyophilization in the Presence of PVP
Applicant has further discovered that polyvinylpyrrolidone (PVP) improves the stability of a lyophilized T7 RNA polymerase:MMLV-RT:Amplification Reagent preparation when combined with trehalose in a buffer before lyophilization to an even greater degree than when the Enzyme:Amplification Reagent is lyophilized in the presence of trehalose alone. This surprising finding suggests that the stability of the lyophilized Enzyme:Amplification Reagent can be maintained to approximately the same or a greater extent by using PVP alone rather than in a lyophilized composition containing trehalose alone or a combination of trehalose and PVP as a cryoprotectant stabilizing agent. Lyophilization of the enzymes may be optimized by dialyzing the purified enzymes as detailed in Example 2 against Dialysis Solution containing TRITON® X-100 or another non-ionic solubilizing agent. The Dialysis Solution does not contain trehalose. Following the buffer exchange step, aliquots of the enzyme solution can be made and various amounts of PVP added to each aliquot. The aliquots can then be given the Enzyme:Amplification Reagent and lyophilized as detailed in Example 2. These lyophilized samples may be incubated at different temperatures for various times and assayed for each enzymatic activity and for the reconstituted reagent's ability to support nucleic acid amplification as in Example 3.
It will be understood by those of skill in the art that the above examples only describe preferred embodiments of the methods and compositions of the present invention, and are not intended to limit or define the invention. Other embodiments are contained in the claims which follow these examples.
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 3(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 48 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(iii) HYPOTHETICAL: NO(iv) ANTI-SENSE: NO(v) FRAGMENT TYPE:(vi) ORIGINAL SOURCE:(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:AATTTAATACGACTCACTATAGGGAGAGAGAAGTGGTCACGGAGGTAC48(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 22 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(iii) HYPOTHETICAL: NO(iv) ANTI-SENSE: NO(v) FRAGMENT TYPE:(vi) ORIGINAL SOURCE:(xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:CATGACTGGTGGACAGCAAATG22(2) INFORMATION FOR SEQ ID NO:3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 26 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(iii) HYPOTHETICAL: NO(iv) ANTI-SENSE: NO(v) FRAGMENT TYPE:(vi) ORIGINAL SOURCE:(xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:CTGCTGGAGATAAACTGGCGTTGTTC26__________________________________________________________________________ | Stabilized enzyme compositions for use in nucleic acid amplification. Compositions are provided for the stabilization of one or more enzymes in a single stabilized formulation. Additional compositions incorporate a dried, stabilized enzyme mixture together with necessary cofactors and enzyme substrates in a single container for use upon rehydration. Also disclosed are methods for making and using stabilized enzyme compositions and kits for nucleic acid amplification incorporating the disclosed compositions. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. Ser. No. 12/846,253, filed Jul. 29, 2010 now U.S. Pat. No. 8,114,789, which is a continuation of U.S. Ser. No. 11/240,189, filed Sep. 30, 2005 now U.S. Pat. No. 7,781,326, which is a continuation of Ser. No. 11/088,072, filed Mar. 23, 2005, now U.S. Pat. No. 7,094,680, which is a continuation of U.S. Ser. No. 09/776,329, filed Feb. 2, 2001, now U.S. Pat. No. 6,951,804, all of which are hereby incorporated by reference in their entireties.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to formation of one or more barrier layers and, more particularly, to one or more barrier layers formed using chemisorption techniques.
2. Description of the Related Art
In manufacturing integrated circuits, one or more barrier layers are often used to inhibit diffusion of one or more materials in metal layers, as well as other impurities from intermediate dielectric layers, into elements underlying such barrier layers, such as transistor gates, capacitor dielectrics, transistor wells, transistor channels, electrical barrier regions, interconnects, among other known elements of integrated circuits.
Though a barrier layer may limit to prevent migration of unwanted materials into such elements, its introduction creates an interface at least in part between itself and one or more metal layers. For sub half-micron (0.5 μm) semiconductor devices, microscopic reaction at an interface between metal and barrier layers can cause degradation of integrated circuits, including but not limited to increased electrical resistance of such metal layers. Accordingly, though barrier layers have become a component for improving reliability of interconnect metallization schemes, it is desirable to mitigate “side effects” caused by introduction of such barrier layers.
Compounds of refractory metals such as, for example, nitrides, borides, and carbides are targets as diffusion barriers because of their chemical inertness and low resistivities (e.g., sheet resistivities typically less than about 200 μΩ-cm). In particular, borides such as, including but not limited to titanium diboride (TiB 2 ), have been used as a barrier material owing to their low sheet resistivities (e.g., resistivities less than about 150 μΩ-cm).
Boride barrier layers are conventionally formed using chemical vapor deposition (CVD) techniques. For example, titanium tetrachloride (TiCl 4 ) may be reacted with diborane (B 2 H 6 ) to form titanium diboride (TiB 2 ) using CVD. However, when Cl-based chemistries are used to form boride barrier layers, reliability problems can occur. In particular, boride layers formed using CVD chlorine-based chemistries typically have a relatively high chlorine (Cl) content, namely, chlorine content greater than about 3 percent. A high chlorine content is undesirable because migrating chlorine from a boride barrier layer into adjacent interconnection layer may increase contact resistance of such interconnection layer and potentially change one or more characteristics of integrated circuits made therewith.
Therefore, a need exists for barrier layers for integrated circuit fabrication with little to no side effects owing to their introduction. Particularly desirable would be a barrier layer useful for interconnect structures.
SUMMARY OF THE INVENTION
An aspect of the present invention is film deposition for integrated circuit fabrication. More particularly, at least one element from a first precursor and at least one element from a second precursor is chemisorbed on a surface. The at least one element from the first precursor and the at least one element from the second precursor are chemisorbed to provide a tantalum-nitride film. This sequence may be repeated to increase tantalum-nitride layer thickness. This type of deposition process is sometimes called atomic layer deposition (ALD). Such a tantalum-nitride layer may be used as a barrier layer.
Another aspect is forming the tantalum-nitride layer using in part annealing of at least one tantalum-nitride sublayer. This annealing may be done with a plasma.
Another aspect is using a plasma source gas as a nitrogen precursor. The plasma source gas may be used to provide a plasma, which may be sequentially reacted or co-reacted with a tantalum containing precursor.
In another aspect, a method of film deposition for integrated circuit fabrication includes forming a tantalum nitride layer by sequentially chemisorbing a tantalum precursor and a nitrogen precursor on a substrate disposed in a process chamber. A nitrogen concentration of the tantalum nitride layer is reduced by exposing the substrate to a plasma annealing process. A metal-containing layer is subsequently deposited on the tantalum nitride layer.
In another aspect, a method of film deposition for integrated circuit fabrication includes forming a tantalum nitride layer with a first nitrogen concentration on a substrate by an atomic layer deposition process. An upper portion of the tantalum nitride layer is exposed to a plasma annealing process to form a tantalum-containing layer with a second nitrogen concentration. A metal-containing layer is then deposited on the tantalum-containing layer.
In another aspect, a method of film deposition for integrated circuit fabrication includes forming a tantalum-containing layer with a sheet resistance of about 1,200 μΩ-cm or less by a plasma annealing process on a tantalum nitride layer deposited by an atomic layer deposition process on a substrate.
In yet another aspect, a method of forming a material on a substrate is disclosed. In one embodiment, the method includes forming a tantalum nitride layer on a substrate disposed in a plasma process chamber by sequentially exposing the substrate to a tantalum precursor and a nitrogen precursor, followed by reducing a nitrogen concentration of the tantalum nitride layer by exposing the substrate to a plasma annealing process. A metal-containing layer is then deposited on the tantalum nitride layer by a deposition process.
These and other aspects of the present invention will be more apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, 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.
FIGS. 1 and 4 depict schematic illustrations of exemplary portions of process systems in accordance with one or more integrated circuit fabrication aspects of the present invention;
FIGS. 2 a - 2 c depict cross-sectional views of a substrate structure at different stages of integrated circuit fabrication;
FIGS. 3 a - 3 c depict cross-sectional views of a substrate at different stages of chemisorption to form a barrier layer; and
FIG. 5 depicts a cross-sectional view of a substrate structure at different stages of integrated circuit fabrication incorporating one or more tantalum-nitride barrier sublayers post plasma anneal.
DETAILED DESCRIPTION
FIG. 1 depicts a schematic illustration of a wafer processing system 10 that can be used to form one or more tantalum-nitride barrier layers in accordance with aspects of the present invention described herein. System 10 comprises process chamber 100 , gas panel 130 , control unit 110 , along with other hardware components such as power supply 106 and vacuum pump 102 . For purposes of clarity, salient features of process chamber 100 are briefly described below.
Process Chamber
Process chamber 100 generally houses a support pedestal 150 , which is used to support a substrate such as a semiconductor wafer 190 within process chamber 100 . Depending on process requirements, semiconductor wafer 190 can be heated to some desired temperature or within some desired temperature range prior to layer formation using heater 170 .
In chamber 100 , wafer support pedestal 150 is heated by an embedded heating element 170 . For example, pedestal 150 may be resistively heated by applying an electric current from an AC power supply 106 to heating element 170 . Wafer 190 is, in turn, heated by pedestal 150 , and may be maintained within a desired process temperature range of, for example, about 20 degrees Celsius to about 500 degrees Celsius.
Temperature sensor 172 , such as a thermocouple, may be embedded in wafer support pedestal 150 to monitor the pedestal temperature of 150 in a conventional manner. For example, measured temperature may be used in a feedback loop to control electric current applied to heating element 170 from power supply 106 , such that wafer temperature can be maintained or controlled at a desired temperature or within a desired temperature range suitable for a process application. Pedestal 150 may optionally be heated using radiant heat (not shown).
Vacuum pump 102 is used to evacuate process gases from process chamber 100 and to help maintain a desired pressure or desired pressure within a pressure range inside chamber 100 . Orifice 120 through a wall of chamber 100 is used to introduce process gases into process chamber 100 . Sizing of orifice 120 conventionally depends on the size of process chamber 100 .
Orifice 120 is coupled to gas panel 130 in part by valve 125 . Gas panel 130 is configured to receive and then provide a resultant process gas from two or more gas sources 135 , 136 to process chamber 100 through orifice 120 and valve 125 . Gas sources 135 , 136 may store precursors in a liquid phase at room temperature, which are later heated when in gas panel 130 to convert them to a vapor-gas phase for introduction into chamber 100 . Gas panel 130 is further configured to receive and then provide a purge gas from purge gas source 138 to process chamber 100 through orifice 120 and valve 125 .
Control unit 110 , such as a programmed personal computer, work station computer, and the like, is configured to control flow of various process gases through gas panel 130 as well as valve 125 during different stages of a wafer process sequence. Illustratively, control unit 110 comprises central processing unit (CPU) 112 , support circuitry 114 , and memory 116 containing associated control software 113 . In addition to control of process gases through gas panel 130 , control unit 110 may be configured to be responsible for automated control of other activities used in wafer processing—such as wafer transport, temperature control, chamber evacuation, among other activities, some of which are described elsewhere herein.
Control unit 110 may be one of any form of general purpose computer processor that can be used in an industrial setting for controlling various chambers and sub-processors. CPU 112 may use any suitable memory 116 , such as random access memory, read only memory, floppy disk drive, hard disk, or any other form of digital storage, local or remote. Various support circuits may be coupled to CPU 112 for supporting system 10 . Software routines 113 as required may be stored in memory 116 or executed by a second computer processor that is remotely located (not shown). Bi-directional communications between control unit 110 and various other components of wafer processing system 10 are handled through numerous signal cables collectively referred to as signal buses 118 , some of which are illustrated in FIG. 1 .
Barrier Layer Formation
FIGS. 2 a - 2 c illustrate exemplary embodiment portions of tantalum-nitride layer formation for integrated circuit fabrication of an interconnect structure in accordance with one or more aspects of the present invention. For purposes of clarity, substrate 200 refers to any workpiece upon which film processing is performed, and substrate structure 250 is used to denote substrate 200 as well as other material layers formed on substrate 200 . Depending on processing stage, substrate 200 may be a silicon semiconductor wafer, or other material layer, which has been formed on wafer 190 (shown in FIG. 1 ).
FIG. 2 a , for example, shows a cross-sectional view of a substrate structure 250 , having a dielectric layer 202 thereon. Dielectric layer 202 may be an oxide, a silicon oxide, carbon-silicon-oxide, a fluoro-silicon, a porous dielectric, or other suitable dielectric formed and patterned to provide contact hole or via 202 H extending to an exposed surface portion 202 T of substrate 200 . More particularly, it will be understood by those with skill in the art that the present invention may be used in a dual damascene process flow.
FIG. 2 b illustratively shows tantalum-nitride layer 204 formed on substrate structure 250 . Tantalum-nitride layer 204 is formed by chemisorbing monolayers of a tantalum containing compound and a nitrogen containing compound on substrate structure 250 .
Referring to FIG. 2 c , after the formation of tantalum-nitride layer 204 , a portion of layer 204 may be removed by etching in a well-known manner to expose a portion 202 C of substrate 200 . Portion 202 C may be part of a transistor gate stack, a capacitor plate, a node, a conductor, or like conductive element. Next, contact layer 206 may be formed thereon, for example, to form an interconnect structure. Contact layer 206 may be selected from a group of aluminum (Al), copper (Cu), tungsten (W), and combinations thereof.
Contact layer 206 may be formed, for example, using chemical vapor deposition (CVD), physical vapor deposition (PVD), electroplating, or a combination thereof. For example, an aluminum (Al) layer may be deposited from a reaction of a gas mixture containing dimethyl aluminum hydride (DMAH) and hydrogen (H 2 ) or argon (Ar) or other DMAH containing mixtures, a CVD copper layer may be deposited from a gas mixture containing Cu(hfac) 2 (copper (II) hexafluoro acetylacetonate), Cu(fod) 2 (copper (II) heptafluoro dimethyl octanediene), Cu(hfac) TMVS (copper (I) hexafluoro acetylacetonate trimethylvinylsilane) or combinations thereof, and a CVD tungsten layer may be deposited from a gas mixture containing tungsten hexafluoride (WF 6 ). A PVD layer is deposited from a copper target, an aluminum target, or a tungsten target.
Moreover, layer 206 may be a refractory metal compound including but not limited to titanium (Ti), tungsten (W), tantalum (Ta), zirconium (Zr), hafnium (Hf), molybdenum (Mo), niobium (Nb), vanadium (V), and chromium (Cr), among others. Conventionally, a refractory metal is combined with reactive species, such as for example chlorine (Cl) or fluorine (F), and is provided with another gas to form a refractory metal compound. For example, titanium tetrachloride (TiCl 4 ), tungsten hexafluoride (WF 6 ), tantalum pentachloride (TaCl 5 ), zirconium tetrachloride (ZrCl 4 ), hafnium tetrachloride (HfCl 4 ), molybdenum pentachloride (MoCl 5 ), niobium pentachloride (NbCl 5 ), vanadium pentachloride (VCl 5 ), or chromium tetrachloride (CrCl 4 ) may be used as a refractory metal-containing compound gas.
Though layer 206 is shown as formed on layer 204 , it should be understood that layer 204 may be used in combination with one or more other barrier layers formed by CVD or PVD. Accordingly, layer 204 need not be in direct contact with layer 206 , but an intervening layer may exist between layer 206 and layer 204 .
Monolayers are chemisorbed by sequentially providing a tantalum containing compound and a nitrogen containing compound to a process chamber. Monolayers of a tantalum containing compound and a nitrogen containing compound are alternately chemisorbed on a substrate 300 as illustratively shown in FIGS. 3 a - 3 c.
FIG. 3 a depicts a cross-sectional view of an exemplary portion of substrate 300 in a stage of integrated circuit fabrication, and more particularly at a stage of barrier layer formation. Tantalum layer 305 is formed by chemisorbing a tantalum-containing compound on surface portion 300 T of substrate 300 by introducing a pulse of a tantalum containing gas 135 (shown in FIG. 1 ) into process chamber 100 (shown in FIG. 1 ). Tantalum containing gas 135 (shown in FIG. 1 ) may be a tantalum based organometallic precursor or a derivative thereof. Examples of such precursors include but are not limited to pentakis(ethylmethylamino) tantalum (PEMAT; Ta(N(Et)Me) 5 ), pentakis(diethylannino) tantalum (PDEAT; Ta(NEt 2 ) 5 ), pentakis(dimethylamino) tantalum (PDMAT; Ta(NMe 2 ) 5 ) or a derivative thereof. Other tantalum containing precursors include TBTDET ( t BuNTa(NEt 2 ) 3 or C 16 H 39 N 4 Ta), tantalum halides (e.g., TaX 5 , where X is F, B or C) or a derivative thereof.
Wafer 190 is maintained approximately below a thermal decomposition temperature of a selected tantalum precursor or a derivative thereof to be used and maintained at a pressure of approximately less than 100 Torr. Additionally, wafer 190 may be heated by heating element 170 . An exemplary temperature range for precursors identified herein is approximately 20 to 400 degrees Celsius. For example, approximately 150 to 300 degrees Celsius may be used for PEMAT.
Though temperatures below a thermal decomposition temperature may be used, it should be understood that other temperatures, namely those above a thermal decomposition temperature, may be used. An example temperature ranges above a thermal decomposition temperature is approximately 400 to 600 degrees Celsius. Accordingly, some thermal decomposition may occur; however, the main, more than 50 percent, deposition activity is by chemisorption. More generally, wafer surface temperature needs to be high enough to induce significant chemisorption of precursors instead of physisorption, but low enough to prevent significant decomposition of precursors. If the amount of decomposition during each precursor deposition is significantly less than a layer, then the primary growth mode will be ALD. Accordingly, such a film will tend to have ALD properties. However, it is possible if a precursor significantly decomposes, but an intermediate reactant is obtained preventing further precursor decomposition after a layer of intermediate reactant is deposited, then an ALD growth mode may still be obtained.
While not wishing to be bound by theory, it is believed that this tantalum-containing precursor combines tantalum atoms with one or more reactive species. During tantalum layer 305 formation, these reactive species form byproducts that are transported from process chamber 100 by vacuum system 102 while leaving tantalum deposited on surface portion 300 T. However, composition and structure of precursors on a surface during atomic-layer deposition (ALD) is not precisely known. A precursor may be in an intermediate state when on a surface of wafer 190 . For example, each layer may contain more than simply elements of tantalum (Ta) or nitrogen (N); rather, the existence of more complex molecules having carbon (C), hydrogen (H), and/or oxygen (O) is probable. Additionally, a surface may saturate after exposure to a precursor forming a layer having more or less than a monolayer of either tantalum (Ta) or nitrogen (N). This composition or structure will depend on available free energy on a surface of wafer 190 , as well as atoms or molecules involved. Once all available sites are occupied by tantalum atoms, further chemisorption of tantalum is blocked, and thus the reaction is self-limiting.
After layer 305 of a tantalum containing compound is chemisorbed onto substrate 300 , excess tantalum containing compound is removed from process chamber 10 by vacuum system 102 (shown in FIG. 1 ). Additionally, a pulse of purge gas 138 (shown in FIG. 1 ) may be supplied to process chamber 10 to facilitate removal of excess tantalum containing compound. Examples of suitable purge gases include but are not limited to helium (He), nitrogen (N 2 ), argon (Ar), and hydrogen (H 2 ), among others, and combinations thereof that may be used.
With continuing reference to FIGS. 3 a - c and renewed reference to FIG. 1 , after process chamber 100 has been purged, a pulse of ammonia gas (NH 3 ) 136 is introduced into process chamber 100 . Process chamber 100 and wafer 190 may be maintained at approximately the same temperature and pressure range as used for formation of layer 305 .
In FIG. 3 b , a layer 307 of nitrogen is illustratively shown as chemisorbed on tantalum layer 305 at least in part in response to introduction of ammonia gas 136 . While not wishing to be bound by theory, it is believed that nitrogen layer 307 is formed in a similar self-limiting manner as was tantalum layer 305 . Each tantalum layer 305 and nitrogen layer 307 in any combination and in direct contact with one another form a sublayer 309 , whether or not either or both or neither is a monolayer. Though ammonia gas is used, other N containing precursors gases may be used including but not limited to N x H y for x and y integers (e.g., N 2 H 4 ), N 2 plasma source, NH 2 N(CH 3 ) 2 , among others.
After an ammonia gas compound is chemisorbed onto tantalum layer 305 on substrate 300 to form nitrogen monolayer 307 , excess ammonia gas compound is removed from process chamber 10 by vacuum system 102 , and additionally, a pulse of purge gas 138 may be supplied to process chamber 10 to facilitate this removal.
Thereafter, as shown in FIG. 3 c , tantalum and nitrogen layer deposition in an alternating sequence may be repeated with interspersed purges until a desired layer 204 thickness is achieved. Tantalum-nitride layer 204 may, for example, have a thickness in a range of approximately 0.0002 microns (2 Angstrom) to about 0.05 microns (500 Angstrom), though a thickness of approximately 0.001 microns (10 Angstrom) to about 0.005 microns (50 Angstrom) may be a sufficient barrier. Moreover, a tantalum-nitride layer 204 may be used as a thin film insulator or dielectric, or may be used as a protective layer for example to prevent corrosion owing to layer 204 being relatively inert or non-reactive. Advantageously, layer 204 may be used to coat any of a variety of geometries.
In FIGS. 3 a - 3 c , tantalum-nitride layer 204 formation is depicted as starting with chemisorption of a tantalum containing compound on substrate 300 followed by chemisorption of a nitrogen containing compound. Alternatively, chemisorption may begin with a layer of a nitrogen containing compound on substrate 300 followed by a layer of a tantalum containing compound.
Pulse time for each pulse of a tantalum containing compound, a nitrogen containing compound, and a purge gas is variable and depends on volume capacity of a deposition chamber 100 employed as well as vacuum system 102 coupled thereto. Similarly, time between each pulse is also variable and depends on volume capacity of process chamber 100 as well as vacuum system 102 coupled thereto. However, in general, wafer 190 surface must be saturated by the end of a pulse time, where pulse time is defined as time a surface is exposed to a precursor. There is some variability here, for example (1) a lower chamber pressure of a precursor will require a longer pulse time; (2) a lower precursor gas flow rate will require a longer time for chamber pressure to rise and stabilize requiring a longer pulse time; and (3) a large-volume chamber will take longer to fill, longer for chamber pressure to stabilize thus requiring a longer pulse time. In general, precursor gases should not mix at or near the wafer surface to prevent co-reaction (a co-reactive embodiment is disclosed elsewhere herein), and thus at least one gas purge or pump evacuation between precursor pulses should be used to prevent mixing.
Generally, a pulse time of less than about 1 second for a tantalum containing compound and a pulse time of less than about 1 second for a nitrogen containing compound is typically sufficient to chemisorb alternating monolayers that comprise tantalum-nitride layer 204 on substrate 300 . A pulse time of less than about 1 second for purge gas 138 is typically sufficient to remove reaction byproducts as well as any residual materials remaining in process chamber 100 .
Sequential deposition as described advantageously provides good step coverage and conformality, due to using a chemisorption mechanism for forming tantalum-nitride layer 204 . With complete or near complete saturation after each exposure of wafer 190 to a precursor, each of uniformity and step coverage is approximately 100 percent. Because atomic layer deposition is used, precision controlled thickness of tantalum-nitride layer 204 may be achieved down to a single layer of atoms. Furthermore, in ALD processes, since it is believed that only about one atomic layer may be absorbed on a topographic surface per “cycle,” deposition area is largely independent of the amount of precursor gas remaining in a reaction chamber once a layer has been formed. By “cycle,” it is meant a sequence of pulse gases, including precursor and purge gases, and optionally one or more pump evacuations. Also, by using ALD, gas-phase reactions between precursors are minimized to reduce generation of unwanted particles.
Co-Reaction
Though it has been described to alternate tantalum and nitrogen containing precursors and purging in between as applied in a sequential manner, another embodiment is to supply tantalum and nitrogen containing precursors simultaneously. Thus, pulses of gases 135 and 136 , namely, tantalum and nitrogen containing compounds, are both applied to chamber 100 at the same time. An example is PEMAT and NH 3 , though other tantalum-organic and nitrogen precursors may be used. Step coverage and conformality is good at approximately 95 to 100 percent for each. Moreover, deposition rate is approximately 0.001 to 0.1 microns per second. Because a co-reaction is used, purging between sequential pulses of alternating precursors is avoided, as is done in ALD.
Wafer surface temperature is maintained high enough to sustain reaction between two precursors. This temperature may be below chemisorption temperature of one or both precursors. Accordingly, temperature should be high enough for sufficient diffusion of molecules or atoms.
Wafer surface temperature is maintained low enough to avoid significant decomposition of precursors. However, more decomposition of precursors may be acceptable for co-reaction than for sequentially reacting precursors in an ALD process. In general, wafer 190 surface diffusion rate of molecules or atoms should be greater than precursors' reaction rate which should be greater precursors' decomposition rate.
For all other details, the above-mentioned description for sequentially applied precursors applies to co-reaction processing.
Plasma Anneal
After forming one or more combinations of layers 305 and 307 , substrate structure 250 may be plasma annealed. Referring to FIG. 4 , there is illustratively shown a schematic diagram of an exemplary portion of a process system 10 P in accordance with an aspect of the present invention. Process system 10 P is similar to process system 10 , except for additions of one or more RF power supplies 410 and 412 , showerhead 400 , gas source 405 , and matching network(s) 411 . Notably, a separate plasma process system may be used; however, by using a CVD/PVD process system 10 P, less handling of substrate structure 250 is involved, as layer 204 may be formed and annealed in a same chamber 100 .
Showerhead 400 and wafer support pedestal 150 provide in part spaced apart electrodes. An electric field may be generated between these electrodes to ignite a process gas introduced into chamber 100 to provide a plasma 415 . In this embodiment, argon is introduced into chamber 100 from gas source 405 to provide an argon plasma. However, if argon is used as a purge gas, gas source 405 may be omitted for gas source 138 .
Conventionally, pedestal 150 is coupled to a source of radio frequency (RF) power source 412 through a matching network 411 , which in turn may be coupled to control unit 110 . Alternatively, RF power source 410 may be coupled to showerhead 400 and matching network 411 , which in turn may be coupled to control unit 110 . Moreover, matching network 411 may comprise different circuits for RF power sources 410 and 412 , and both RF power sources 410 and 412 may be coupled to showerhead 400 and pedestal 150 , respectively.
With continuing reference to FIG. 4 and renewed reference to FIG. 3 c , substrate structure 250 having one or more iterations or tantalum-nitride sublayers 309 is located in process chamber 401 . Argon (Ar) gas from gas source 405 is introduced into chamber 401 to plasma anneal substrate structure 250 . While not wishing to be bound by theory, it is believed that plasma annealing reduces nitrogen content of one or more sublayers 309 by sputtering off nitrogen, which in turn reduces resistivity. In other words, plasma annealing is believed to make tantalum-nitride layer 204 more tantalum-rich as compared to a non-plasma annealed tantalum-nitride layer 204 . For example, a 1:1 Ta:N film may be annealed to a 2:1 Ta:N film. Tantalum-nitride films having a sheet resistance of approximately equal to or less than 1200 microohms-cm for 0.004 micron (40 Angstrom) films may be achieved.
It will be appreciated that other non-chemically reactive gases with respect to layer 204 may be used for physically displacing nitrogen from layer 204 , including but not limited to neon (Ne), xenon (Xe), helium (He), and hydrogen (H 2 ). Generally, for a plasma-gas that does not chemically react with a tantalum-nitride film, it is desirable to have a plasma-gas atom or molecule with an atomic-mass closer to N than to Ta in order to have preferential sputtering of the N. However, a chemically reactive process may be used where a gas is selected which preferentially reacts for removal of N while leaving Ta.
Referring to FIG. 5 , there is illustratively shown a cross sectional view of layer 204 after plasma annealing in accordance with a portion of an exemplary embodiment of the present invention. Plasma annealing may be done after formation of each nitrogen layer 307 , or may be done after formation of a plurality of layers 307 . With respect to the latter, plasma annealing may take place after approximately every 0.003 to 0.005 microns (30 to 50 Angstroms) of layer 204 or after formation of approximately every 7 to 10 sublayers 309 . However, plasma annealing may be done after formation of a sublayer 309 , which is approximately 0.0001 to 0.0004 microns (1 to 4 Angstroms).
Plasma annealing with argon may be done with a wafer temperature in a range of approximately 20 to 450 degrees Celsius and a chamber pressure of approximately 0.1 to 50 Torr with a flow rate of argon in a range of approximately 10 to 2,000 standard cubic centimeters per minute (sccm) with a plasma treatment time approximately equal to or greater than one second. Generally, a tantalum-nitride film should be annealed at a temperature, which does not melt, sublime, or decompose such a tantalum-nitride film.
The specific process conditions disclosed in the above description are meant for illustrative purposes only. Other combinations of process parameters such as precursor and inert gases, flow ranges, pressure ranges and temperature ranges may be used in forming a tantalum-nitride layer in accordance with one or more aspects of the present invention.
Although several preferred embodiments, which incorporate the teachings of the present invention, have been shown and described in detail, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings. By way of example and not limitation, it will be apparent to those skilled in the art that the above-described formation is directed at atomic layer CVD (ALCVD); however, low temperature CVD may be used as described with respect to co-reacting precursors. Accordingly, layers 305 and 307 need not be monolayers. Moreover, it will be appreciated that the above described embodiments of the present invention will be particularly useful in forming one or more barrier layers for interconnects on semiconductor devices having a wide range of applications.
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 method of forming a material on a substrate is disclosed. In one embodiment, the method includes forming a tantalum nitride layer on a substrate disposed in a plasma process chamber by sequentially exposing the substrate to a tantalum precursor and a nitrogen precursor, followed by reducing a nitrogen concentration of the tantalum nitride layer by exposing the substrate to a plasma annealing process. A metal-containing layer is subsequently deposited on the tantalum nitride layer. | 2 |
FIELD OF THE INVENTION
The present invention relates to a method for exchanging rectangular sliver cans between a can transport vehicle and a can storage device disposed at a can filling station for filling cans with slivers which has an area for receiving and storing empty cans and an area for storing full cans by means of a can transport vehicle, and wherein empty cans are brought to the filling station between the two areas and after being filled with sliver are returned and placed in the area for storing full cans.
BACKGROUND OF THE INVENTION
Many suggestions have already been made for automating the transport of sliver cans from the can filling stations of a sliver producing machine to the textile machines which process the sliver. Driverless can transport vehicles have been suggested, particularly for supplying the work stations of the textile machines which process the sliver, and are known, for example, from German Patent Publication DE 43 23 726 A1. These vehicles are able to automatically deliver empty cans to the can filling stations, to pick up full cans freshly filled with sliver, to transport them to the textile machines and to set them down at the work stations of the machines which require sliver after an empty sliver can which had previously been standing in an empty storage space has been picked up. Such a can transport vehicle relieves the machine operator of heavy manual labor.
The can transport vehicle known from the above-mentioned publication transports so-called rectangular cans which are sufficiently narrow that they can be placed under a respective work station of a textile machine processing the sliver, for example an open end spinning machine, and only take up the appropriate space of the work station which is assigned to them. Rectangular cans with these dimensions considerably simplify the supply of the work stations of the textile machines processing the sliver.
In the same way in which the exchange of empty cans for filled cans is possible without problems at the textile machines, the exchange of empty cans for full cans must also take place reliably and without interruption at the filling stations.
So-called can storage devices are known for making a smooth can change possible at the can filling stations, namely the transfer of empty cans from the can transport vehicle to the can filling station and the placement of filled cans from the can filling station onto the can transport vehicle. The storage devices which are located upstream of the filling station offer the opportunity of unloading empty sliver cans from a can transport vehicle while an empty can is being filled with sliver and subsequently loading the can transport vehicle with ready, sliver-filled cans.
Exemplary embodiments of can storage devices at can filling stations are known from International Patent Publication WO 91/18135. Once a can transport vehicle has been positioned at such a storage device, the empty cans are unloaded and the full cans are loaded successively at a single position of the can transport vehicle. One respective empty can is replaced by one full can, which takes up time. In accordance with a representative embodiment, the unloaded cans are moved on a belt to a transfer point, from there into the can filling station by means of a perpendicularly extending chain with carriers, from there back to the transfer point, and from there are moved away by means of a further belt. Thus, it is not clear how the full cans waiting in the storage device may be exactly associated with parking places on the can transport vehicle. Since the occupancy of the storage spaces in the storage device is not monitored, a can exchange on a can transport vehicle is only possible if, in the empty can storage area the same number of empty spaces behind the already moved empty cans lies opposite the parking places on the can transport vehicle, which docks in a predetermined position. In the area of the full cans, the full cans to be exchanged must be located opposite the parking places on the can transport vehicle in the loading position.
OBJECT AND SUMMARY OF THE INVENTION
It is accordingly an object of the present invention to provide an improved method for the exchange of empty sliver cans for full cans at a loading station for a can transport vehicle.
This object is attained by means of the novel method and apparatus of the present invention for exchanging rectangular sliver cans between a can transport vehicle and a can storage device disposed at a can filling station for filling cans with slivers, wherein the can transport vehicle has a plurality of aligned can parking spaces, the can storage device has a section for storing empty cans in a plurality of aligned empty can spaces and a section for storing full cans in a plurality of aligned full can spaces, and the filling station is disposed between the empty can storage section and the full can storage section. Briefly summarized, under the present invention, the can transport vehicle is positioned by appropriate means at the empty can storage section of the can storage device, empty cans are transferred to the empty can storage section from the can transport vehicle, the empty cans from the empty can storage section are moved to the filling station to be filled with sliver, the filled cans are moved from the filling station to the full can storage section, the can transport vehicle is positioned at the full can storage section of the can storage device, and full cans from the full can storage section are transferred to the can transport vehicle positioned at the can storage device.
In accordance with the invention, the transferring of empty cans to the empty can storage section is basically accomplished by determining the arrangement of empty cans already stored in the empty can spaces of the empty can storage section and moving such arrangement of empty cans by a sufficient number of empty can spaces that the empty can spaces located opposite the parking spaces having empty cans on the can transport vehicle to be transferred are unoccupied, and subsequent to the transferring of empty cans to the empty can storage section, moving the already-stored arrangement of empty cans and the empty cans transferred from the can transport vehicle to occupy the empty can spaces of the empty can storage section most closely adjacent the filling station.
The transferring of full cans from the full can storage section is accomplished by determining the arrangement of full cans already stored in the full can spaces of the full can storage section and moving such arrangement of full cans by a sufficient number of full can spaces that a forwardmost one of the full can spaces occupied by a full can is located opposite a forwardmost occupyable can space on the can transport vehicle, and subsequent to the transferring of full cans to the can transport vehicle, moving any full cans remaining at the full can storage section to occupy the full can spaces most closely adjacent the filling station.
In a preferred embodiment, the empty cans and the filled cans are moved as indicated by respective moving means which include can carrier elements spaced from one another by a distance of one can width. Another can moving means with spaced can carrier elements for supporting a single can is provided at the transfer space to the filling station, and means are provided for selectively coupling the can moving means at the transfer space alternatingly or mutually with the means for moving empty cans and with the means for moving filled cans. The means for moving empty cans preferably includes a controllable drive means for selectively displacing the empty can storage section by a predeterminable distance and the means for moving filled cans likewise has an independent controllable drive means for selectively displacing the full can storage section by a predeterminable distance.
Equipping the respective can moving means in the empty can storage section and in the full can storage section of the can storage device with carriers allows the positionally correct placement of the cans onto and removal from these moving means. The carriers make it possible for all cans standing on the moving means, and therefore in the storage device, to take up identical positions in respect to each other. The further moving means provided at the transfer point to the filling station between the full can storage section and the empty can storage section is exactly dimensioned to conform to the width of a can and has two couplings to permit coupling alternatingly or together with the moving means of the full can storage section and with the moving means of the empty can storage section. Since both the moving means in the full can storage section and the moving means in the empty can storage section have individual drive means, the can moving means in the area of the transfer location can be coupled with the can moving means of the empty can storage section during the receipt of an empty can and with the can moving means of the full can storage section during the transfer of a full can.
If an empty can is filled at the filling station, the can space defined at the transfer location is empty. Since the can transport vehicle at the can storage device has a fixed position in the empty can storage section and a fixed position in the full can storage section, it is necessary in the course of transferring empty cans to the empty can storage section to displace the cans in the can storage device by a predeterminable distance such that the empty cans can be simultaneously transferred from the can transport vehicle in one work step into the empty can storage section. In the process, the cans in the empty can storage section, at the transfer point and in the full can storage section are displaced by the respective can moving means such that the empty cans removed from the can transport vehicle immediately follow the empty cans which are already on the storage device in the empty can storage section. For the purpose of transferring empty cans by means of the can transport vehicle positioned at the can storage area to the empty can storage section, the defined arrangement of cans already standing in the can storage device is displaced transversely to the transfer direction sufficiently until empty storage spaces are located opposite all empty cans to be transferred. If the empty cans to be transferred from the can transport vehicle follow the last empty can standing in the empty can storage section, storage spaces are advantageously saved and the outlay for technical control devices for eliminating the gaps is unnecessary.
During the transfer operation, the empty space normally at the transfer location is maintained between the stored empty cans and the stored full cans and, after the empty cans have been transferred, the respective can moving means are operated to return this empty can space back into its original position at the transfer location. For this purpose, the cans which were already present prior to the transfer operation must again take up their original places. In this manner, the transfer of an empty can to the filling station at the transfer point and the subsequent placement of the same can in the same place in the sequence of cans is possible. Since the occupation of the individual storage spaces of the can storage device is monitored by means of sensors, the displacement of an empty space can advantageously be identified easily. The moving means are moved in reverse by the number of the displaced storage spaces, so that the empty space previously present at the transfer location returns again to its initial position at the transfer location.
So that the number of full cans which the can transport vehicle can receive for one trip can be taken up in one work step without gaps in the alignment of cans of the respective storage areas being created, the alignment of full cans present in the full can storage section is displaced transversely to the can transfer direction such that, as viewed in the direction of travel of the can transport vehicle, the first full can standing in the can storage device is located opposite the first parking space of the vehicle available to be occupied. Thus, the displacement of the cans takes place over a predeterminable distance which is comprised of the defined number of can spaces which are displaced.
A can transport vehicle can unload empty cans in the empty can storage section only if the number of the still empty storage spaces corresponds to the number of empty cans to be delivered. The can transport vehicle leaves the full can storage section only when the can parking places on the can transport vehicle intended for the transport of full cans are occupied by full cans.
The advantages of the invention become apparent in particular when the empty can storage section as well as the full can storage section have more storage spaces than the can transport vehicle. Thus, the can transport vehicle can always discharge empty cans and take on full cans independently of the occupancy of the storage sections of the storage device. If required, empty cans temporarily move into the full can storage section and full cans into the empty can storage section in the process.
The invention will be explained in more detail by means of an exemplary embodiment as well as by means of can changing situations at the can storage device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view of the can storage device at a filling station with a can transport vehicle positioned in front of the empty can storage section;
FIG. 2 shows the arrangement of the transport means of the can storage device in a top view;
FIG. 3 shows the arrangement of the transport means of the can storage device in a front view;
FIGS. 4 and 5 show the transfer of empty cans by a can transport vehicle to a partially filled storage empty can storage section;
FIGS. 6 and 7 show the subsequent takeover of full cans by the can transport vehicle;
FIG. 8 shows the subsequent return of the remaining cans in the initial position;
FIGS. 9 and 10 show the transfer of empty cans by means of a can transport vehicle to a can storage device, whose empty can storage section is not occupied and whose full can storage section is completely occupied;
FIG. 11 shows the subsequent takeover of full cans by the can transport vehicle;
FIG. 12 shows the subsequent return of the remaining cans into the base position;
FIG. 13 shows a so-called block exchange, for example during a batch change, the transfer of empty cans by a can transport vehicle;
FIG. 14 shows the subsequent transfer of full cans to the can transport vehicle; and
FIG. 15 shows the subsequent return of the remaining cans into the base position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the accompanying drawings and initially to FIG. 1, a can storage device S is schematically shown wherein stored sliver cans stand on a flat continuous sheet metal plate 1 which rests on a frame (not shown). The can storage device S is divided into a section or area for storing empty cans BL and a section or area for storing full cans BV, separated from one another by a can transfer location U. Empty cans are moved from this transfer location U to a can filling station F to be loaded with sliver, after which the filled cans are again pushed back onto the can storage device S at the transfer location U.
A pair of parallel belts extend in the longitudinal direction of the storage device S along both the empty can storage section BL and the full can storage section BV to serve as the means for transporting the cans in the respective sections. More specifically, two belts 2a and 2b are disposed parallel with each other in the empty can storage section BL within recesses or indentations 3 in the sheet metal plate 2 such that their upper belt surfaces lie below the level of the sheet metal plate 1. Similarly, two belts 4a and 4b also extend parallel in respect to each other in the full can storage section BV in symmetrical relation to the belts in the empty can storage section BL. Thus, the belts 4a and 4b and the belts 2a or 2b are respectively disposed in alignment with one another.
Each of the belts 2a, 2b, 4a, 4b are respectively equipped with can carrier devices or elements 5 spaced along the belts at a distance equal to the width of a sliver can K. For example, these carriers can be upstanding pins or plates standing on their short edges, which make it possible to displace the cans on the sheet metal plate 1 during the synchronous movement of the belts. The carriers 5 respectively define the boundaries of individual can storage spaces BL1 to BLn or BV1 to BVn in the respective storage sections BL and BV. Instead of the sheet metal plate 1, it is also possible to provide elongate bars to extend rightwardly and leftwardly in parallel with the belts for supporting the cans.
The belts 2a and 2b are trained around coaxially arranged reversible drive rollers 6', 6" and 7', 7" with the drive rollers 6' and 6" being driven by a motor 8. The belts 4a and 4b similarly are trained about the reversible drive rollers 9', 9", 10' and 10", with the drive rollers 9' and 9" being driven by a motor 11.
Two parallel belts 12a and 12b extend across the area of the transfer location U intermediate the belts 2a, 2b, 4a and 4b, and are dimensioned in length to be exactly the width of the transfer location U, which in turn is the width of a sliver can. The belts 12a and 12b are also equipped with carrier elements 5 which are likewise spaced apart from each other by the width of a can. The belts 12a and 12b extend around two supporting rollers 13 and 14, which are rotatably seated coaxially on the shafts 7a, 10a, respectively, independently of the reversing rollers 7', 7" and 10', 10". In this manner, the belts 12a and 12b can be selectively coupled either with the belts 2a and 2b or with the belts 4a and 4b by the provision of respective switchable couplings 15 , 16 disposed between the supporting rollers 13, 14 and the respective shafts 7a, 10a (see FIG. 2). Thus, if the belts 12a and 12b are intended to run together with the belts 2a and 2b, the coupling 15 between the supporting roller 13 and the shaft 7a is engaged. If the belts 12a and 12b are intended to run together with the belts 4a and 4b, the coupling 16 between the supporting roller 14 and the shaft 10a is engaged. The carriers 5 are arranged on the belts 12a and 12b such that they are respectively located in alignment with the positions of the carriers 5 on the belts 2a, 2b, 4a and 4b. Thus, if a can is standing at the transfer location U, the carriers 5 of the belts 2a and 2b rest against the one side and the carriers 5 of the belts 4a and 4b against the other side, while at the same time the carriers 5 of the belts 12a and 12b enclose the can standing on them. During the respective coupling of the belts 12a and 12b to either the belts 2a and 2b or the belts 4a and 4b, the respective carriers run synchronously.
FIG. 3 shows the arrangement of the transport means of the can storage device in a front view. Two full sliver cans Kv are depicted upstanding on the sheet metal plate 1 in the full can storage section BV, with the carriers 5 bordering the respective can storage locations BV1 and BV2. The belts 2a, 2b, as well as 4a and 4b and the belts 12a and 12b, lie in a common plane, either in a depression in the sheet metal plate 1 or within slits formed in the sheet metal plate 1 through which the carriers 5 project to engage and transport the cans. In place of continuous endless belts, it is also possible to utilize chains. The belts must be disposed in respect to the bottom sheet metal plate i such that, when the cans are displaced transversely to their lengthwise dimension, they do not interfere with the transfer location U and are not damaged. When transferring empty cans into the empty can storage section BL in the direction of the arrow 17, or when transferring full cans from the full can storage section BV in the direction of the arrow 18, the belts also must not hamper the displacement of the cans. The same requirements apply to the arrangement of the belts 12a and 12b in the area of the transfer location U, where the transfer of empty cans Kl to the filling station F and the transfer of filled cans Kv from the filling station F takes place in the direction indicated by the two-headed arrow 19.
As can be seen in FIG. 1, the can storage device S has a total of 16 storage spaces, which are arranged symmetrically at each side of the can parking space defined by the transfer location U, the empty can storage section BL comprising eight storage spaces and the full can storage section BV also comprising eight storage spaces. In the circumstance illustrated in FIG. 1, three empty cans Kl are standing in the empty can storage section BL while five full cans Kv are standing in the full can storage section BV. Another can Kf is standing in the filling position at the filling station F on a section 20 having a filling head 21 suitable for filling rectangular cans with sliver in coordination with a device 23 which is suitable for executing a reciprocating movement 22 of the can. For example, the device 23 can be a carriage which is adapted to perform the reciprocating movement by a further mechanism 24 which also moves an empty can from the transfer location U to the filling station F and back into the transfer location U when the can is filled. Alternatively, a manipulating device may be provided by which the empty cans can be pulled or pushed out of the transfer location U and under the filling head 21, for example by means of a gripper device, and then the filled can returned to the transfer location by means of the same manipulating device. A testing station (not shown) can be installed between the transfer location U of the can storage device S and the filling station F for detecting sliver remnants in the empty cans moving to the filling station and for detecting possible damage of the empty cans and the testing station may be equipped to perform the emptying of sliver remnants from the cans if required. The transfer location can also be equipped in accordance with German Patent Publication DE 41 30 463 A1, which discloses the removal of empty cans from an endless belt to a filling station and the return of the filled cans to the endless transport belt.
When a can has been filled at the filling station F and has been transferred to the transfer location U, the coupling 16 is engaged to connect the belts 12a and 12b with the belts 4a and 4b, whereupon the motor 11 is actuated to cause the belts to move in unison rightwardly in the direction of the arrow 25 in FIG. 1 by exactly one can width. In the process, the freshly filled can is pulled into the full can storage section BV, and the transfer location is freed for transfer of another empty can Kl from the empty can storage section BL. The coupling 16 may then be disengaged and the coupling 15 may be engaged to couple the belts 12a and 12b with the belts 2a and 2b for transferring another empty can Kl from the empty can storage section BL to the transfer location U. Upon actuation of the motor 8, the coupled belts are displaced in unison rightwardly by one can width in the direction of the arrow 26 in FIG. 1. As a result, the empty can Kl which was previously adjacent the transfer location U moves into the transfer location U and is moved out of the transfer location U and under the filling head 21 of the section 20 by means of the device 24.
As can be further seen from FIG. 1, a can transport vehicle KF has been positioned in front of the empty can storage section BL of the storage device S. The can transport vehicle KF has six parking spaces 27a to 27f for cans. By way of example, in the instant circumstance illustrated, the can transport vehicle KF supports five empty cans Kl in the spaces 27a to 27e, with the space 27f empty. The can transport vehicle KF is supported on three wheels 28a to 28c as indicated in broken lines, of which the forward wheel 28a can be driven and steered. The can transport vehicle moves only in the indicated direction 29 under the guidance of an induction track 30, for example.
The can transport vehicle KF can be positioned at two locations alongside the can storage device S, namely, at the empty can storage section BL and at the full can storage section BV. Positioning takes place by means of sensors appropriately placed on the can transport vehicle KF and on the can storage device S. More specifically, a sensor 31 is disposed at the front end of the can transport vehicle KF on the side thereof facing the can storage device S and forwardly of the parking spaces 27a-27f for the cans, as viewed in the direction of travel of the can transport vehicle KF. A compatible sensor PL is disposed on the can storage device S at the empty can storage section BL, and another like sensor PV is disposed at the full can storage section BV. The sensors PL, PV and 31 are adapted to function not only for position determination of the can transport vehicle KF, but are also designed for the wireless electronic exchange of data bidirectionally between the can transport vehicle KF and a central control device 32 of the can storage device S.
The can transport vehicle KF with its load of empty cans Kl moves along the induction track 30 in the direction of travel 29 until the sensors PL and 31 are located directly opposite each other. In this position, the can transport vehicle KF is correctly positioned in front of the empty can storage section BL for the transferral of the empty cans Kl thereto. The transfer of the empty cans to the can storage device is initiated by means of a bidirectional exchange of data between a control device 33 of the can transport vehicle KF and the control device 32 of the can storage device S. For this purpose, it is first necessary to determine which can storage spaces in the empty can storage area BL are occupied, which is determined by means of sensors 34 associated with the individual spaces. As illustrated in FIG. 1, of the eight storage spaces BL1 to BL8 of the empty can storage area BL, the three storage spaces BL1 to BL3 most closely adjacent to the transfer location U are occupied by empty cans Kl. Thus, in this circumstance, the can transport vehicle KF would not be capable of transferring the empty can Kl in the first parking space 27a to the occupied adjacent space of the empty can storage area BL of the can storage device S. Thus, in accordance with the present invention, it is provided under such circumstances for each of the cans already stored at the empty can storage area BL to be respectively displaced rightwardly (as viewed in FIG. 1) toward the transfer location U by a sufficient number of storage spaces (in this case, one storage space), so that the transfer of all empty cans Kl from the parking spaces 27a to 27e on the can transport vehicle KF can take place.
How the transfer of empty cans from the can transport vehicle KF to the empty can storage section BL of the can storage device S takes place and how subsequently the transfer of filled cans from the full can storage section BV to the can transport vehicle KF takes place will be explained in more detail by means of the schematic drawings of FIGS. 4-8.
The situation shown in FIG. 1 is again represented schematically in FIG. 4. Here, and in the further exemplary sequences of FIGS. 5-8, the representation of the details of the can storage device S and the can transport vehicle KF as well as the filling station F is omitted and, for sake of clarity and simplicity, only the configuration of the empty cans Kl and the full cans Kv in the can storage device S and the occupation of the can transport vehicle KF with cans to the extent required for understanding the invention are represented.
So that all empty cans Kl can be transferred from the can transport vehicle KF to the empty can storage section BL of the can storage device S, all of the cans stored by the can storage device S, including both the empty cans Kl in the empty can storage section BL and the full cans Kv in the full can storage section BV, are moved to the right in the direction of the arrow 35 by one storage space, as represented in FIG. 5. As a result, the storage space BL3 in the empty can storage section BL is freed for receiving the empty can Kl from the adjacent first parking space 27a of the can transport vehicle KF. For this purpose, the couplings 15 and 16 are engaged and each of the belts 2a, 2b, 12a, 12b, 4a, 4b are moved in unison by one can width by means of the motors 11 and 8.
In the instant exemplary circumstance of FIGS. 1 and 4, it was only necessary to move the belts by one storage space width. Since the can transport vehicle KF may only transfer its empty cans to the storage device S if the same number of storage spaces in the empty can storage section BL of the storage device S are free as the number of empty cans carried by the can transport vehicle, it will be understood to be necessary that the belts of the storage device S be moved by the same respective number of storage spaces of the storage device S as the number of cans on the parking spaces of the can transport vehicle which stand opposite the cans stored in the empty can storage section BL once the can transport vehicle has been positioned. Thus, the belts are moved by the number of storage spaces necessary until the sensors 34 no longer detect cans on the storage spaces BV1-BV8 which are opposite the occupied parking spaces of the can transport vehicle KF.
In FIG. 5 the transfer of all empty cans Kl of the can transport vehicle KF to the empty can storage section BL is in the process of taking place, as indicated by the arrow 17, and may be performed, for example, with the aid of devices disposed on the can transport vehicle such as are known from German Patent Publication DE 43 23 726 A1.
So that a correct transfer of the cans takes place and no can projects past the contour of the can storage device, a so-called gap control is utilized wherein a photoelectric barrier 36 is used to monitor and control the gap between the can transport vehicle KF and the can storage device S. Specifically, a light beam is directed from a light source 37 to a receiver 38 through the area between the can transport vehicle KF and the can storage device S which should be open and unobstructed if the can transfer was successfully completed. If the gap is indicated to be clear after the can exchange has been performed by the detection of the light beam by the receiver 38, the correct transfer of the cans has taken place and the can transport vehicle can now be moved into position at the full can storage section BV in order to take on therefrom a corresponding load of full cans.
To this end, the can transport vehicle KF moves forward along the track 30 until the sensor 31 on the vehicle KF is located directly opposite the sensor PV associated with the full can storage section BV. In FIG. 6, the can transport vehicle is shown to have taken up such position opposite the full can storage section BV. So that a correct transfer of the full cans Kv to the can transport vehicle KF can take place in accordance with the present invention, all cans in the can storage device S must be moved forward by a sufficient number of the storage spaces BV1-BV8 until the full cans Kv in the full can storage section BV are opposite the parking spaces on the can transport vehicle KF which are intended for occupation with full cans. In this regard, it is necessary in order that a can transport vehicle can perform the first can exchange at a work station of a textile machine that the vehicle must always have an empty parking space on which it can receive an empty can during the first can exchange. For this reason, the first can parking space 27a on the can transport vehicle remains empty. Therefore, in the situation illustrated in FIG. 6 of the drawings wherein the five full cans Kv occupy the storage spaces BV2 to BV6, it is necessary to move each of the five full cans Kv forwardly by one storage space so as to occupy the storage spaces BV3 to BV7, whereby the cans are located opposite and can be transferred to the can parking spaces 27b to 27f on the can transport vehicle. The storage space BV8 is not occupied by a full can since, as explained, the can parking space 27a must remain empty. As will be noted, the empty cans at the empty can storage section BL also are moved forwardly each by one storage space to maintain a single can space between the empty cans and the full cans, as more fully explained below.
In FIG. 7, the five full cans having been moved forwardly as described, the simultaneous transfer of the five full cans Kv to the can transport vehicle KF is shown to be taking place. The correct transfer of the cans is also monitored and controlled in this case by the photoelectric barrier 36 as described above. FIG. 8 depicts the can storage device S after the can transport vehicle has moved away with its load of full cans and the remaining empty cans have been moved back into the base storage positions BL1-BL8.
In accordance with the invention, the single can space between the full cans and the empty cans normally existing at the transfer location U must always remain free during any positioning movements of the cans, whether such positioning is to facilitate the transfer of empty cans to the storage device or the transfer of full cans from the storage device. Hence, the return of the empty cans into the base position, i.e. the initial position, can be easily performed simply by moving the cans rearwardly toward the empty can storage section BL until no can is detected at the transfer location U by the sensor 34 disposed thereat. In the circumstance illustrated in FIG. 8, the storage space at the transfer location U which had not been previously occupied has returned into its initial, or base, position. A comparison of FIG. 5 with FIG. 8 thus reflects that, because of the transfer of the five empty cans from the transport vehicle KF in FIG. 5, all eight storage spaces of the empty can storage section BL of the can storage device S have now been occupied.
FIGS. 9 and 10 show the transfer of empty cans to a completely free empty can storage section BL, and further illustrate that only a single can parking space may exist as the so-called transfer location U between the empty can storage section BL and the full can storage section BV. Only then is it possible to transfer all cans positionally correctly from a can transport vehicle or to transfer filled cans correctly onto a can transport vehicle. Likewise, the process of transferring empty cans to and filled cans from the storage device S and transferring cans to and from the filling station must be designed such that no other gap or space is created, since any such gap cannot be closed once created, and would, in the final analysis, cause a wrong placement of cans.
In FIG. 9, the can transport vehicle KF has been positioned in front of the empty can storage section BL, all storage spaces BL1 to BL8 of which are unoccupied. However, in the situation illustrated, all storage spaces BV1-BV8 of the full can storage section BV are occupied by full cans Kv. Since the can transport vehicle KF can only be positioned according to the sensors 31, PL in the single disposition shown relative to the storage device S for the process of transferring empty cans at the empty can storage section BL, the full cans Kv must be moved rearwardly toward and into the empty can storage section BL sufficiently that, following the transfer of the empty cans, only a space of one can width will remain unoccupied between the transferred empty cans Kl and the full cans By. Thereafter, the belts can be actuated to move the unoccupied space to the transfer location U.
FIG. 10 depicts the transfer of the empty cans from the transport vehicle KL to the empty can storage section BL of the can storage device S. As can be seen, the full cans Kv from the full can storage section BV have been moved into the empty can storage section BL in the direction of the arrow 39 by only a sufficient number of storage spaces that a gap of only one storage space will remain between the five empty cans Kl to be transferred and the full cans Kv once the simultaneous can transfer is completed. After the empty can transfer is completed, the control device 32 controls the return movement of the filled cans Kv and the transferred empty cans Kl by monitoring the sensors 34 on the parking spaces to maintain only one parking space unoccupied between the parking spaces which receive empty cans and the parking spaces holding full cans.
In the case where the can transport vehicle would not take on full cans, the conveyors are actuated to move the full cans rightwardly to displace the unoccupied space existing at the storage space BL2 to the transfer location U. In the case where the can transport vehicle KF is to take on full cans, the vehicle KF once positioned in front of the full can storage section under the control of the positioning sensors 31, PV would not yet be loaded with full cans in the existing circumstance of FIG. 10, even though all eight storage spaces in the full can storage section BV may be occupied by the eight full cans Kv. As can be seen from FIG. 11, the full cans are first moved sufficiently that the final storage space BV8 is unoccupied adjacent the parking space 27a of the vehicle KF which, as aforementioned, is required to remain unoccupied for purposes of a subsequent empty can exchange. For this reason, the eight full cans which originally occupied all of the storage spaces BV1-BV8 of the full can storage section BV in FIG. 9, are moved by only one storage space to occupy the transfer location and the first seven full can storage spaces BV1-BV7, leaving the storage space BV8 empty. The cans are now arranged in the area of the full cans BV in such a way that only the parking spaces 27b to 27f of the can transport vehicle KF can be occupied by the full cans Kv on the storage spaces BV3 to BV7. FIG. 11 depicts this transfer operation underway. FIG. 12 shows the can storage device S following the transfer of the full cans and after the return movement of the cans rightwardly into the base position wherein the previously unoccupied space at BL1 in FIG. 11 has been moved into the transfer location U.
A so-called block exchange, which is always performed, for example, when a batch change takes place at a machine, is illustrated by means of FIGS. 14 and 15. In such case, since no individual cans are exchanged subsequently at the associated downstream machine because the empty cans are completely exchanged for full cans at the machines, all parking spaces on the can transport vehicle, including the space 27a, are occupied by empty cans which are then transferred to the can storage device, and a full can transfer is subsequently performed from the can storage device to occupy all parking spaces on the can transport vehicle with full cans,.
For this reason the can transport vehicle KF in FIG. 13 carries five empty cans Kl for transfer to the five unoccupied storage spaces in the empty can storage section BL. It is of course a requirement for a block exchange that after the empty cans have been transferred, the can transport vehicle is to loaded to full occupancy of its parking spaces with full cans. In the present situation illustrated in FIG. 14, six full cans Kv are stored by the full can storage section BV and, thus, the can transport vehicle can take on all of them. Since in a block exchange the parking space 27a of the can transport vehicle is also occupied by a full can, it is necessary before the transfer of the full cans takes place that the full cans be moved forwardly until all six cans in the full can storage section BV are positioned adjacent the six parking places of the can transport vehicle in its position determined by the sensors 31, PV, i.e., the cans are moved to occupy the storage spaces BV3-BV8 as shown in FIG. 14. However, the eight empty cans stored in the empty can storage section BL are also correspondingly moved forwardly, so that only one storage space remains between the empty cans and the full cans.
After the transfer of the full cans to the can transport vehicle depicted in FIG. 14, the eight empty cans are moved rearwardly until they occupy the eight storage spaces BL1-BL8 whereby the unoccupied space existing in FIG. 14 at the storage space BV2 is moved into the transfer location U, as represented in FIG. 15.
It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. | In the automatic transport of rectangular spinning cans between a can filling station and the work stations of textile machines which process sliver, it is known to arrange a can storage device in association with the can filling station, with a section of the can storage device for receiving empty cans from a traveling can transport vehicle and a section for storing and transferring full cans to the can transport vehicle, and with the can filling station between these two sections. The present invention contemplates the ordered and positionally exact transfer of the cans to and from the can transport vehicle by transferring of empty cans from the can transport vehicle to the empty can storage section such that the transferred empty cans immediately follow the empty cans already stored thereat. In the transfer of full cans to the can transport vehicle, a leading one of the full cans to be transferred is transferred into a corresponding leading one of the occupyable parking spaces on the can transport vehicle. Following a can transfer operation, the arrangement of the empty and full cans remaining in the can storage device is moved so as to leave a transfer space at the filling station unoccupied. | 3 |
This application claims the benefit of U.S. provisional application No. 60/163,566, filed Nov. 5, 1999.
TECHNICAL FIELD
The present invention relates to treating biomass in order to enhance its value or rank. More particularly, the invention provides a process for the treatment of coal or other biomass to efficiently convert the selected raw feed stock from low rank into a high-grade fuel capable of increased heat release per unit of fuel. This invention is particularly targeted to serve the utility, commercial and industrial markets. It is also very capable of supplying a low smoke fuel for domestic use, such as home heating and cooking use.
BACKGROUND OF THE INVENTION
Biomass is one of the largest and most readily available energy sources known to man. Biomass is found in immature forms, such as wood, shells, husks and peat. Vast amounts of biomass are also available in the form of lignite, sub-bituminous, bituminous and anthracite coal. Man has been releasing the energy trapped in the aforementioned materials ever since he discovered and was able to master fire. The inefficient release of these vast energy reserves, however, has resulted in a degradation of the quality of the atmosphere and the environment. The increasing demand for energy, created by man's insatiable appetite for the products made available by an industrialized society, have created a need to release this energy in a safe, clean and environmentally responsible manner.
Prior processes have recognized that heating coal removes the moisture and, as a result, enhances the rank and BTU production of the coal. It is also known that this pyrolysis activity alters the complex hydrocarbons present in coal to a simpler set of hydrocarbons. This molecular transformation results in a more readily combustible coal. Processes have been developed using high temperature (in excess of the coal's auto-ignition point). This high temperature art requires the control of the atmosphere in which this heated coal is treated in order to eliminate the auto-ignition of the coal. However, these high temperature, atmosphere-controlling devices produce an unstable product. The “shocked or face powdered” coal produced in these furnaces created a need to reassemble this treated material into a manufactured form (briquette). Processes were then developed which include grinding of the coal into a material less than {fraction (3/16)}″ (fines). These fines are pyrolized to reduce the moisture and volatile matter, usually at temperatures ranging from 400 F. to 700 F. These fines are then mixed with a binder, which is either inherent or foreign to the process. The resulting mixture is formed into predetermined sized briquettes. The resulting briquettes are low or void of moisture, modestly stable and devolatilized to some degree.
These prior processes require from 2 to 6 hours to complete. They are slow and costly, both in capitalization costs and production costs. A need exists for an improved process for treating coal to increase its rank while reducing the time and cost of completing the process. The present invention seeks to fulfill that need.
SUMMARY OF THE INVENTION
It has now been discovered, according to the present invention, that it is possible to treat coal or other biomass under conditions and over a relatively short time period to enhance its rank to produce a fuel of 12,500 to 13,000 BTU/lb content or higher. In accordance with one aspect, the invention provides a process for treating biomass, typically coal, to increase its rank, wherein a biomass feedstock is heated to remove moisture and volatiles from the feedstock, and the treated biomass is thereafter collected. The term “remove moisture” as used herein, means that the contents of moisture (water) is reduced to less than 2% by weight. The reduction of volatile material and organic hydrocarbons is a controlled part of the process whereby the time of exposure, the temperature, and the atmospheric conditions are all predicated upon the volatile makeup of the initial feed stock and the desired volatile makeup of the finished product. This finished product can be 25% by weight or greater volatile matter, for example 25-35%, or 3% or less by weight volatile matter, more usually 5-15% by weight. The present invention provides for detailed control over the end result of the raw feed stock with regard to the volatile matter and other characteristics of the final product.
In a further aspect, a portion of the steam and volatiles removed during the heat treatment of the feedstock in a heating means are recycled back into the heating means, along with a predetermined mixture of liquid hydrocarbons, to provide a non-oxidizing atmosphere which will prevent ignition of the feedstock during the heating step. The term “non-oxidizing atmosphere”, as used herein with respect to the entire treatment process, means an atmosphere wherein the oxygen content is typically less than 2% oxygen, usually 0.001-1% oxygen, more usually 0.25 to 0.75% oxygen, by volume.
In yet a further aspect there is provided coal of increased rank produced according to the process of the invention.
In yet another aspect, the invention provides briquettes formed from coal treated according to the process of the invention. The briquettes may be provided with a waterproof coating to improve stability, ignition properties and to extend shelf life.
The process of the invention allows for the controlled volatilization and removal of moisture and organic volatiles, while maintaining the majority of the biomass' natural structural integrity, with reduced disintegration to powder form, thereby converting low grade fuel of, for example, 7500 BTU/lb. or less, into high-grade fuel of 12,500 BTU/lb. or higher. The process greatly reduces capitalization and production costs required to arrive at the desired result, thus substantially increasing the cost effectiveness and production rate over prior processes. This invention also greatly reduces the time necessary to complete the process from the existing processes of hours to 15 minutes or less, more usually 5-10 minutes.
BRIEF DESCRIPTION OF THE DRAWING
Embodiments of the invention will now be described in more detail with reference to the accompanying drawings, in which:
FIG. 1 is a typical retort used for carrying out the process of the invention; and
FIG. 2 is a schematic illustration of a multi-chamber retort useful in carrying out the invention.
It will be noted that this invention is not limited to the use of a rotary retort, as there are other types of equipment that are also capable of supporting this invention. However, for purposes of description, the rotary retort is referred to in the description which follows.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
It is understood that the present invention can be used on all types of biomass substrate. Biomass for purposes of the present invention means any form of wood, shells, husks, peat and other combustible material of organic origin. Examples of biomass particularly suitable for use in the present invention are lignite, sub-bituminous coal, bituminous coal and anthracite coal. For ease of discussion, the following description will be with reference to coal, which is understood to include all forms of coal, especially lignite, sub-bituminous, bituminous and anthracite coal.
Referring to FIG. 1, there is shown a conventional retort 2 for carrying out an embodiment of the invention. The process may be carried out using a cylindrical rotating retort or a rotary hearth continual moving gratetype furnace. For ease of description, the following discussion is with respect to the cylindrical rotating retort type. The retort is typically inclined at a small angle to the horizontal, usually 5-15 degrees to the horizontal, to facilitate gravitational movement of the coal being treated through the apparatus, although horizontal retorts may also be used, if desired. The retort 2 is provided with a chamber 4 , which may be a single chamber or may be multiple chambers. The chamber(s) is heated by way of a furnace 6 encircling the exterior of the chamber(s) 4 . The furnace is provided with external heating means, such as gas burners, electric coils or coal burners 8 . The chamber(s) 4 is in communication with a feedstock inlet 10 through which raw coal 12 is admitted to the chamber(s) 4 , and an outlet 14 through which treated coal 16 passes for further downstream processing. As coal enters the chamber(s) 4 through inlet 10 , it is heated by way of radiation from the hot walls of the chamber(s) 4 as the coal progresses through the chamber(s).
In the embodiment illustrated in FIG. 2, the process utilizes five separate chambers. FIG. 2 shows a retort 20 having five chambers 22 , 24 , 26 , 28 , 30 . Each chamber is provided with an aperture at each end to permit entry of the feedstock and exit of treated feedstock to the next downstream chamber. The chambers are each separated from each other by closure means 32 , typically a shutter arrangement which can be opened and closed across the diameter of the chamber, to retain feedstock in a particular chamber under specific processing conditions which may be different and often are different from conditions present in adjacent chambers.
By removing direct contact between hot gases and the coal, it is possible to avoid combustion of the coal, while also controlling the temperature and atmospheric conditions to achieve optimum processing parameters, such as inert atmospheres created at least in part by volatilization of materials from the coal, and non-oxidizing atmospheres created by addition of vapors, such as steam or dried nitrogen, along with selected liquid hydrocarbons. The captured volatiles, which are expelled during the invention process, contain hydrocarbons. The hydrocarbons for example have formulae ranging from CH 4 to C 8 H 18 . There are times that the carbon fraction can be as high as C 25 . The hydrocarbons being expelled and the quantities of expelled hydrocarbons that are available for reissue into the heated chamber during the invention process will determine the hydrocarbon formulae and the hydrocarbon quantity needed to adequately supplement the heating chamber's atmosphere. The correct atmosphere formulation required to produce the desired volatile expulsion rate and volatile expulsion amount is predicated upon the characteristics of the raw feedstock and the targeted condition of the product as it exits each chamber of the invention.
The chamber(s) 4 is provided with entry and exit port means 18 , 20 for admission of gases and liquid hydrocarbons for controlling the atmosphere, as well as cooling gases. Similar entry and exit ports 34 , 36 are present in the retort illustrated in FIG. 2 . The chamber(s) may be modified to remove internal augers and stirring devices to afford simple reliable operation. The retort is provided with conventional devices for controlling the flow rate and temperature of the gases passing through the system. The retort is also provided with means 22 for rotating the chamber(s) 4 to permit more even distribution of heat and passage of gases throughout the coal substrate during the treatment process.
It is desirable to subject the coal feedstock to a preliminary drying stage prior to crushing. Typically, most of the surface moisture of the coal, that is at least 85% by weight of the moisture, is reduced in the preliminary drying stage. The preliminary drying step is typically carried out using a conventional air-drying apparatus with air at a temperature of 200-250 F. or a centrifugal type of surface moisture drying equipment. A typical drying apparatus for coarse coal may be a CMI 48 and for fine coal may be a CMI 35 or any other standard coal drying apparatus that is typically used in the coal industry. This invention is not dependent upon pre-drying the coal feed stock. However, this pre-drying step can add to the efficiency of the overall process.
Following preliminary drying, the coal is crushed using conventional crushing apparatus e.g. a Gunstock double roll crusher or a McClanahan type crusher. This crushing will reduce the feedstock to an average size of about 1-2 inches, with the top size (the largest size permitted) more usually being in the region of about 2″. This is accomplished by using a 2″ screen. Any coal that is too large to pass through the screen into the feed stockpile may be recycled through the crusher.
The dried crushed coal is then introduced into the first stage(s) of treatment within the chamber(s) 8 of the retort 2 . The invention described herein refers to a five chamber heating facility. However, the invention process may be performed in as few as one chamber or as many as seven. The efficiency of the invention process, however, is most affective in the five chambers as described herein.
The five stages of this process can be, but are not limited to being, contained in a cylindrical rotating retort or a rotary hearth continual moving grate type furnace. Each of these heating facilities is capable of continually moving the product from one chamber to the next. These chambers are capable of controlling the inert atmospheres during the time in which the coal is present.
In the first chamber 22 (see FIG. 2 ), the temperature of the coal feedstock is raised to 400-750° F., more usually about 550° F., for about 2-4 minutes, more usually about 3 minutes. During this first stage of the process, any surface moisture that has survived the pre-drying step will be completely driven off of the raw feed stock. The inert moisture that is present in the feedstock will be reduced to 2-5% by weight. The resultant percentage of moisture that is present after completion of this step will be predicated upon the amount of inert moisture that was present in the raw feed stock. Some raw feedstock will begin to lose a portion of its volatile matter at the temperatures present in this first stage. However, any loss of volatiles during the first stage of the invention is insignificant. It is in the second and subsequent stages of the invention where control is exercised in the removal of volatiles from the raw feedstock.
Biomass, such as coal, contains many volatile materials, which are expelled when the coal is exposed to high temperatures. These volatile materials posses individual characteristics which differentiate them from one another, and the temperature at which these volatile materials are normally expelled from the biomass is one such differentiating characteristic. The time in which these volatile materials are normally expelled from the biomass is another such differentiating characteristic. The present invention is concerned in one aspect with the time and temperature characteristics of the volatile materials contained in the selected biomass (raw feedstock). The present invention influences certain volatiles contained within the feedstock in a manner as to allow for a uniform expulsion of a majority of these and other volatiles. For example, volatile “A”, when exposed to 900° F. may be expelled from the feedstock in 10 seconds, whereas volatile “B”, when exposed to 900° F. might be expelled from the feedstock in 20 seconds. The present invention introduces a hydrocarbon or mixture of hydrocarbons into the heated atmosphere surrounding the feedstock, which acts to curtail the speed with which volatile “A” is expelled. In this way, the invention controls the expulsion rate of most volatiles present in the feedstock such that the majority of the volatiles are expelled at an equal or similar rate. This “control” over the expulsion rate of volatiles allows for treatment of the feedstock while avoiding fracturing and fissuring that would routinely occur without employing this “control”. The “control” is achieved by utilizing conventional testing and monitoring equipment.
The retention time of the coal in the first stage will vary depending upon the initial moisture content of the coal feedstock. The inert atmosphere inside the chamber(s) is controlled by adjusting the retention time and temperature and by the reintroduction of volatiles and liquid hydrocarbons into the chamber(s), as necessary.
In order to maintain an essentially non-oxidizing atmosphere during the treatment process, the oxygen content of the atmosphere in the first chamber, and throughout the entire treatment process, is typically less than 2% oxygen, usually 0.001-1% oxygen, more usually 0.25 to 0.75%, by volume. The temperature for the evolution of volatile gases and atmospheric agents and the reduction in product mass takes place between 400° F. and 2200° F.
According to one aspect, control of the atmosphere is partially achieved by the introduction of liquid hydrocarbons into the chamber(s). These hydrocarbons range from hydrocarbons with formulas such as CH 4 to C 8 H 18 . There are times that the carbon fraction can be as high as C 25 . When these liquid hydrocarbons are introduced, the coal interacts with these hydrocarbons in a manner that promotes the molecular behavior necessary to arrive at the desired result of this invention. When the coal is heated to the aforementioned temperatures, some of the volatile matter in the coal is converted from a solid, into a liquid and eventually into a gas. The amount of volatile matter and moisture that is driven off in gaseous form is predicated on the characteristics and make-up of the raw feedstock. The gases that are released from the solid material are either recycled or liquified and captured.
The remaining solid material expands due to its elevated temperature. The expansion of the material and the release of some if its mass result in a lump that now has fissures and voids. The natural tendency of a shocked mass at this point is to fall apart and be reduced into a face powder. To prevent this, the present invention provides for the careful and timely introduction of liquid hydrocarbons and processed (dried) nitrogen to substantially reduce disintegration of the lumps as a result of this shocking affect. This introduction of liquid hydrocarbons has a bridging affect on the fissures in the lumps and provides an adhesive on the surface and incorporated within the body of the lumps that counters the tendency of the shocked feedstock to deteriorate into the consistency of a face powder. The timing, type, and amounts of liquid hydrocarbon(s) and processed nitrogen that are introduced are carefully predetermined by a preliminary examination of the raw feedstock. This preliminary examination of the raw feedstock is done by conventional methods. The information gathered from this preliminary examination provides the necessary data that is used to determine and to produce the mixture of hydrocarbons and processed nitrogen to be employed in the process.
This hydrocarbon formula will be timely and appropriately introduced into the heating chamber(s) during the multiple stage(s) of this invention. The actual formula used to produce the proper atmosphere will include liquid hydrocarbons that range from hydrocarbons with formulas such as CH 4 to C 8 H 18 . There are times that the carbon fraction can be as high as C25. The formula which is introduced into the heat chamber(s) and the feedstock's time of exposure are predicated on, but not limited to, the volatile makeup, characteristics, and chemical makeup of the feedstock.
The treated coal from the first stage is transferred into the second chamber of the retort. In this second chamber, the temperature of the material is elevated to about 900-1100° F. for example about 1000° F. In this second stage, the feedstock relinquishes the majority of its volatile matter, i.e. greater than 80% by weight of the volatiles that are removed, are removed in the second stage. This second stage is important in that it requires a carefully controlled atmosphere mixture of liquid hydrocarbons and processed nitrogen. The second stage of the process is where the feedstock is most likely to be “shocked” into a “face powder” . The coal after exposure in this second chamber(s), has survived the negative characteristics normally associated with this heat induced “shock”. For some end uses, the material that completes this second stage of the process would satisfy the specifications of some end users. When this situation occur s, the second stage treated material is collected and cooled by exposing the coal to a dry cooling gas, which is typically substantially free of oxygen. The cooling gas usually has moisture content of less than 1% by weight.
The atmosphere in the second chamber is very carefully monitored, measurably supplemented, and managed with conventional gauges that are installed in the heat chamber(s). It is found that the coal typically undergoes at least some agglomeration at temperatures between 900° F. and 1100° F. and particularly at temperatures above 1100° F. For this reason, it is preferred to keep the temperature in this stage of the process generally less than 1100° F.
The coal is retained in the second chamber(s) for a period up to about 5 minutes, typically 1-4 minutes, more usually about 3.5 minutes. This phase of the process results in the expulsion of the majority of volatiles from the coal. During this phase, the coal undergoes shrinkage as the coal loses a portion of its mass. Typically, weight loss is in the range of 5-50% of the coal's initial mass, more usually a weight loss in the range of 5-25% by weight, depending upon the makeup and characteristics of the raw feed stock. One type of feed stock may not give up its volatile matter as readily as another type. A feed stock may have as much as 60% volatile matter while another may only have an initial volatile content of 15%. This invention allows for a conventional pre-process evaluation of the feed stock. The data collected from this evaluation is then used to calculate the mixture of liquid hydrocarbons and processed nitrogen that are carefully maintained within the heating chamber(s). This “custom design” processing feature allows this invention to successfully treat a variety of biomass with a variety of initial characteristics.
The atmosphere in the chamber(s) is controlled so that the coal maintains a majority of its natural structural integrity. The term “natural structural integrity”, as used herein, means the tendency of the post-crushed natural lump coal (coal averaging in size from 1-2 inches) not to significantly disintegrate to form a powder. The expression “majority of its natural structural integrity”, as used herein, means that more than 50% by weight, more usually 75% or more, typically 85 to 95%, of the coal does not undergo disintegration during the multiple chamber(s) process. The structural integrity possessed by the coal as a result of the invention is such that during normal handling, even though the coal is more fragile due to some loss of mass, the coal sustains its average particle size range of 1-2 inches. By carefully controlling the atmosphere in the chamber(s), the coal can be heated to as high as 2200° F. for extended periods of time to remove volatiles, without inducing substantial agglomeration, i.e. less than 10% by weight agglomeration is observed, more usually less than 8% by weight, and without significantly degrading the structural integrity of the coal. The material is now ready to be transferred into the third chamber(s) of the process.
The coal and the controlled atmosphere are transferred from the second chamber(s) into the third chamber(s), where the third phase of the process is executed. The coal in this phase is raised to a temperature of 1300-1550° F. for example about 1450° F., and retained at that temperature for about 2-4 minutes, typically about 3 minutes to produce coal having a moisture content of less than 2%. By the third stage, the moisture content has been reduced to the lowest economically feasible level possible utilizing this invention. The volatile content of the feedstock by the completion of stage 3 is typically within 10% of the targeted volatile content of the finished product. The atmosphere in the third chamber(s) is carefully monitored with conventional gauges that are installed in the heat chamber(s) and appropriately supplemented with liquid hydrocarbons and processed nitrogen in order to maintain the structural integrity of the material. For some end uses, the material that completes this third stage of the process would satisfy the specifications of some end users. When this situation occurs, the third stage treated material would be collected and processed cooled by exposing the coal to a dry substantially oxygen free cooling gas having a moisture content of less than 1% by weight. The coal and the controlled atmosphere are then transferred into the fourth chamber(s).
In the fourth phase of the present process, the temperature of the material is raised in the chamber(s) to 2000-2400° F., typically about 2200° F. for 3-5 minutes to produce coal having a moisture content of less than 2% and a volatile content of between 5-15%. The atmosphere of the fourth phase is again very critically controlled and managed with conventional gauges that are installed in the heat chamber in order for this invention to provide for the favored results. The retention time of the coal in the chamber in this stage of the process and the actual temperature required in this fourth phase are dependent upon the percentage of volatile matter to mass that is optimally desired in the finished material. This fourth stage is the final opportunity for this process to attain the desired volatile qualities requested of the finished product. In order for a feedstock that is resistant to volatile expulsion, to be brought into targeted volatile standards, the high temperatures of the fourth phase will either be elevated to produce the desired results or the exposure time of the unfinished products will be increased in order to achieve the desired results. It is possible for both temperature and exposure time to be adjusted in order to allow for a less cooperative feed stock to expel the excess volatile matter.
An objective of the present process is to reduce the percentage of volatile matter to the desired percentage as requested by the end user, which for this discussion is less than 15% by weight. At this stage in the process, the remaining volatile matter is generally composed of high boiling organic hydrocarbon materials occluded within the interstices of the coal pieces. The amount of moisture remaining after this stage is less than 2% by weight.
The coal and the controlled atmosphere are moved into the fifth chamber(s) of the apparatus where the processed coal is cooled by exposing the coal to a dry cooling gas. The cooling gas is typically a non-oxidizing gas, and may be an inert gas such as argon or may be nitrogen or other suitable non-oxidizing gas. The cooling gas is substantially free of oxygen. As used herein, the expression “substantially free of oxygen” means typically less than 2% oxygen, usually about 0.001-1% oxygen, more usually about 0.25 to 0.75% oxygen, by volume. The atmosphere in the previous chamber(s)s is also substantially free of oxygen as that term is defined herein. The cooling gas is essentially dry upon admission to the chamber(s), and may be countercurrent or cocurrent to the direction of flow of the coal undergoing treatment. The cooling gas is essentially dry, having a moisture content of less than 1% by weight, typically 0.5% by weight or less. The cooling gas is typically passed over the coal at a volume flow rate of about 0.2-0.5 pounds per minute. The coal in this chamber(s) at this stage of the process is cooled at a rate which does not affecting the structural integrity of the coal.
When the material has cooled to 250° F., it may be optionally separated into fines (particles less than ¼″) and coal having a size in the range of ¼″ to 2″. This material separation is accomplished by conventional means, using by wave of a sieve or screen of appropriate mesh size.
The fines may be optionally delivered to a pelletizing or briquetting process where these 250° F. fines may be conventionally mixed with a biodegradable coating (binder and igniter) that is in a liquid state at 250° F. This mixed material is then formed into the desired sized pellet using conventional methods. If the treated coal were destined to go directly into a furnace, i.e. a utility use, this coating process would not be necessary. When the product is scheduled for conventional handling and the end user requires a material that is resistant to breakage, this coating process is employed. This coating also adds a low-level ignition point, which provides a valuable quality, especially when the end user is a domestic user.
As the newly formed pellets or briquettes cool below 150° F., they become structurally stable. This structurally stabilizing coating material adds significantly to the coal's ability to withstand disintegration due to conventional handling methods. The coating also adds a low heat ignition quality to the material, which allow s the material to be easily ignited. The coating does not significantly add to the off-gases produced when the material is ignited. A further advantage, which the biodegradable coating adds to the finished product, is that the finished product is extremely moisture resistant which provides for a multi-year shelf life.
Typically the non-fines obtained via the screening process are immediately coated with the aforementioned conventional binder/igniter. This coating provides an enhanced structural integrity to the natural lump material that has been weakened in the aforementioned process, together with enhanced-moisture resistance. The coated coal's reduced tendency to undergo disintegration upon handling provides for a much more marketable product as it does in the aforementioned processed pellets/briquettes. As this coated, natural lump coal cools below 150° F., it acquires the same favorable qualities as does the manufactured pellet or briquette as mentioned above.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, and is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | Process for treating coal to enhance its rank, wherein the temperature of the material is gradually increased in a controlled set of atmospheres, to allow for the reduction of surface and inherent moisture and the controlled reduction of volatile matter while maintaining the coal's natural structural integrity. The process reduces the time, capitalization, and production costs required to produce coal of enhanced rank, thus substantially increasing the cost effectiveness and production rate over prior processes. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 62/099,386, filed Jan. 2, 2015.
BACKGROUND OF THE INVENTION
[0002] There are numerous applications for analyte sensing within the field of health care. One useful configuration that has been discussed for some time is the combination of an analyte sensor with a hollow catheter for drug delivery. This configuration is particularly attractive to people with insulin-treated diabetes because such a device could reduce their percutaneous device burden. Rather than using a separate insulin infusion catheter and a continuous glucose monitor sensor, they could use a single combined device instead.
[0003] There are many different strategies for glucose sensing that could be considered for such a combined sensing catheter. Prior art exists for the use of optical sensing technologies for glucose. U.S.20130040404A1 to Crane et al teaches an optical glucose sensor built upon an optical waveguide. U.S. 20050118726 A1 to Schultz et al teaches an optical sensing method based upon a glucose-binding fusion protein. WO 2013036492 A1 to Aasmul et al teaches an optical fiber-based sensor having a hollow fiber filled with a glucose binding assay. WO 2000064492 A1 by Ballerstadt et al teaches a porous hollow sensor containing porous beads for the optical determination of analyte concentration. Alternative sensing strategies such as viscometry have also been disclosed (eg U.S. Pat. No. 6,210,326 B1 to Ehwald). However, none of these has found commercial adoption, nor are they well-suited to pairing with drug infusion in a single device.
[0004] A more common analyte sensor design is based upon the principle of amperometry, in which analytes are detected by the electrochemical conversion of the analyte of interest on the sensor surface. The sensing electrodes are commonly fabricated through the use of sputtered or evaporated thin films deposited on the surface of a substrate. Often, indicating electrodes (also known as working electrodes) are made of platinum, gold or carbon. When a positively biased indicating electrode is coupled with a reference electrode, such as silver/silver chloride, analytes can be amperometrically detected. With the addition of an enzyme layer such as glucose oxidase, a thin film sensor can be made quite specific for certain analytes. When thin films of metal electrodes are deposited on an appropriate polymer film such as polyimide, the resulting sensor has the added advantage of flexibility. Users might find a rigid catheter or needle uncomfortable or painful.
[0005] One problem with electrodes made from metallic thin films is fragility; the layers can delaminate when exposed to physical trauma such as impact, flexion, shear stresses, and tensile stresses. For example, Azoubi et al found that durability of thin film electrodes is limited. More specifically, a large number of flexion cycles led to materials failure, a phenomenon known as cycle fatigue (1). While the durability of a thin film may be sufficient for short-term applications, longer term ambulatory sensing applications require a much greater ability to withstand trauma. In the case of indwelling subcutaneous sensors, the sensor must withstand repeated flexion over a period of time lasting from 3 to 7 days or beyond. Over this extended duration, the sensor may experience thousands of bending cycles due to the movement of the patient. In the case of a long-distance runner, a sensor could easily experience 20,000-40,000 cycles over the course of a single workout alone. In Azoubi's bench top studies, thin films were shown to suffer cracking in as few as 500 cycles (1); this phenomenon is aggravated by immersion in warm, wet, high-salt environments such as those presented by mammalian blood or subcutaneous interstitial fluid. Consequently, the electrodes in the leading commercially-available CGM sensor (made by Dexcom, Inc) are constructed from durable solid wires rather than thin films. Examples of this design can be found in many patent disclosures. U.S. Pat. No. 8,812,072 B2 to Brister et al teaches a wire-based variable stiffness transcutaneous medical device. U.S. Pat. No. 8,543,184 B2 to Boock et al teaches a wire-based transcutaneous implantable continuous analyte sensor with a silicone-based membrane. U.S. Pat. No. 8,060,174 B2 to Simpson et al teaches a biointerface for a wire-based sensing electrode. U.S. Pat. No. 8,515,519 B2 to Brister et al teaches a transcutaneous analyte sensor assembly. U.S. Pat. No. 5,165,407 to Wilson et al teaches a flexible, solid wire-based glucose sensor. U.S. Pat. No. 7,471,972 B2 to Rhodes et al teaches a multi-electrode wire-based sensor. U.S. Pat. No. 9,131,885 B2 to Simpson et al teaches a multi-layer sensor having a solid core. However, a wire or rod has a solid core and is thus not compatible with drug delivery, which requires a hollow lumen. None of these devices would be suitable for combined analyte sensing and drug delivery due to their lack of a hollow lumen.
[0006] Earlier inventors have disclosed sensors coupled with hollow catheters. In U.S. Pat. No. 8,886,273 to Li, Kamath, and Yang, the inventors teach a glucose sensor disposed within a hollow catheter. More specifically, the sensor in this invention is disposed inside a larger diameter catheter that is indwelled inside a blood vessel. Whereas such an invention is appropriate for measuring a liquid (blood) that exists within a catheter, such a design is not appropriate for a sensing catheter which is intended for measuring glucose in subcutaneous fatty tissue. For use in subcutaneous tissue, the sensing elements must be on the outer wall of the hollow catheter. Stated differently, a “wire sensor within a tube” or “tube within a tube” design will not allow proper function in subcutaneous tissue. For drug delivery, the inner lumen must be hollow. Similarly, in U.S. Pat. No. 6,695,958 B1 to Adam et al, the authors disclose a device having sensing elements located in the interior of the hollow part and designed to measure analytes in the interior lumen. However, for a subcutaneous sensing catheter similar to CGM devices in common use, it is necessary to have an open interior (lumen) to allow for drug delivery into the body. In our invention, the outer wall, which is not in contact with a drug and which is bathed with glucose-containing subcutaneous interstitial fluid, is the optimal location for the sensing elements.
[0007] Other sensor configurations have been disclosed that require the withdrawal of fluid samples from the body in order for sensing to occur. U.S. Pat. No. 5,174,291 A to Schoonen et al discloses a hollow fiber-based glucose sensor that involves dialysis with a test solution. CA 2347378 A1 to Knoll et al incorporates a hollow probe for the withdrawal of interstitial fluid. EP 1327881 A1 to Beck at al teaches a hollow electrochemical cell with internal sensing elements requiring the drawing up of the fluid sample. U.S. Pat. No. 8,277,636 B2 to Sode et al teaches a glucose dehydrogenase-based sensor incorporating an interstitial fluid sampling device. U.S. 20060000710 A1 to Weidenhaupt et al teaches a method for determining glucose concentration that requires the use of a device that has an external sensor coupled with a fluid-sampling pump. U.S. 20110180405 A1 to Chinnayelka teaches a sensor incorporating a hollow member and a lancet for the sampling of interstitial fluid. U.S. Pat. No. 5,176,632 A to Bernardi teaches a system that incorporates a microdialysis-based sensor. U.S. Pat. No. 6,605,048 B1 to Levin et al teaches a sampling device that incorporates a vacuum for the drawing up of a blood sample from the skin surface. None of these would permit ongoing delivery of a drug with simultaneous exposure of the sensor to interstitial fluid. Consequently, these systems are not compatible with continuous subcutaneous drug infusion.
[0008] Other sensor configurations have been disclosed that utilize microneedles to reduce the invasiveness of the measurement technique, such as the invention that is the subject of WO2006116605 A2 to Liepmann et al. However, the chief problem with microneedle arrays is the difficulty of keeping all the microneedles indwelled in mammalian tissue during body movement. Because microneedles are short in length, some of the needles will have a tendency to come out of tissue when the person moves suddenly or forcefully. This problem of unintentional explantation renders them unsuitable for multiday use in an outpatient setting.
[0009] In order to fabricate a combined sensor/catheter, one can incorporate biosensing elements into the wall of a hollow needle or catheter. An inexpensive strategy is the fabrication of arrays of planar sensing strips which are then individualized. One sensing strip is attached to the surface of each catheter. The most obvious and simplest strategy would be to directly deposit metal (e.g. platinum, gold) indicating thin film indicating electrodes and silver reference thin film reference electrodes on the underlying polymer layer such as polyimide or polyester. Common methods of depositing the platinum and silver electrodes include sputtering, thermal evaporation, printing, silk screening, or use of an adhesive layer on a thin metal film. After deposition, the silver would subsequently be chloridized using an electrolytic procedure (electrochloridization) or by immersion in ferric chloride. This planar sensor substrate can then be wrapped around and glued to the surface of a needle or tube in order to integrate the sensor with the drug delivery catheter. The use of a flexible metalized substrate has substantial advantages in terms of low cost of production, as hundreds of devices can be manufactured in batch processing using photolithographic techniques, mature technologies developed over several decades by the electronics industry. One such design, disclosed in WO2002039086 to Ramey et al, incorporates printed electrode films. However, after carrying out many studies in animals, we have observed a major problem with sensing catheters made of thin film metal electrodes deposited over a polymeric layer. These sensors exhibited frequent delamination and general lack of durability. This invention teaches methods by which the durability of sensing catheters can be markedly improved.
SUMMARY OF THE INVENTION
[0010] This invention pertains to the concept of creating a sheet or strip that contains one or more amperometric biosensing electrodes and integrating this sheet or strip into the outer wall of a hollow catheter (cannula). When thin film metal electrode materials are placed directly over polymeric surfaces (with or without underlying thin adhesion layers) the device becomes fragile. The electrode films and other elements of the sensor often delaminate or break apart during impact, and therefore, such a device is not adequate for use as an indwelling catheter. In fact, substantial electrode delamination can be seen after only a few hours of in vivo use. In the experience of the inventors, whether or not a 100 nm tie (adhesion) layer of gold is deposited under the electrodes, such a design leads to a frequent separation of the gold layer from the polyimide, frequent separation of the platinum or silver electrode films from the gold layer, and frequent fragmentation of the metal layers.
[0011] Thus, an improved sensor composition is required in order to enhance durability. During exploration of alternative designs, we found that inclusion of a metallic foil beneath (underlying) the thin film metal electrodes markedly improved durability and fatigue resistance, while maintaining sufficient flexibility for fabrication and use as a biosensor in mammals. The use of the term “foil” indicates a metal layer that is at least 2 micrometers (μm) in thickness, that is, much thicker than the thin film layer typically deposited by sputtering, evaporation, printing or electroplating. Foils are usually made by rolling a metal stock through a pair of hardened metal rolls. Hammering of the stock is an alternative way of making the foil. Alternatively, metal foils can be made by electroplating, sputtering, thermal evaporation and deposition of metal inks. Rolled or hammered metal foils have very high internal cohesive forces. More specifically, the process of rolling achieves a tightly-packed crystal and grain structure which increases strength. If necessary, the rolled metal can be annealed to reduce brittleness and reform the natural grain structure. Discussions of the beneficial mechanical properties of foils can be found in three scientific articles listed elsewhere in this document and attached (1-3).
[0012] For these reasons, a metal foil (underneath the thin electrode film) is well-suited for the purpose of durability as described in this invention. It is well known that for the materials of a biosensor to be sufficiently durable, all layers must have a high degree of adhesion to the adjacent layers.
[0013] In our studies, we found that the presence of an underlying metal foil dramatically enhanced resistance to cyclic fatigue. More specifically, we found that the physical integrity of a foil having a thickness of 2-15 μm was orders of magnitude greater than a sputtered film (unattached to an underlying foil) with a thickness of 50-100 nm. Of course, in order to yield a functioning sensor, there is a need for the foil and associated layers to undergo a process of patterning (to create the dimensions for the indicating and reference electrodes, the contact pads and the interconnect traces). A foil-polymer laminate was chosen as a substrate that would permit low-cost patterning and assembly into a durable, fatigue-resistant sensor.
BRIEF DESCRIPTION OF DRAWINGS
[0014] FIG. 1 , a cross-section, shows layers of a sensing catheter whose design makes it susceptible to cyclic fatigue. The outer layer 1 is composed of sensing membranes that include an enzyme and other materials such as a redox mediator and a permselective polymer layer. In deeper layers, there is a layer of thin film metal electrode 2 . Depending on the location of the cross-section, the electrode 2 can be an indicating, reference electrodes, or counter-auxiliary electrode. Deeper still is a thin film adhesion layer 3 (such as gold); a polymer layer 4 (such as polyimide); an adhesive layer 5 ; a tube 6 such as a stainless steel tube; and a central opening or lumen 7 . When sensing catheters fabricated with this design are subcutaneously placed in mammals, there are frequent occurrences of delamination of certain junctions or fragmentation of certain layers, designated here with the label “fragile interface.”
[0015] FIG. 2 , a cross-section, shows another example of a sensing catheter whose design makes it susceptible to cyclic fatigue. In this figure, no adhesion layer is present and the thin film metal electrode layer 2 is directly deposited on to a polymer substrate 4 such as polyimide. The label “fragile interface” denotes the specific junction that is not durable.
[0016] FIG. 3 , a cross-section, shows the layers of a rigid sensing catheter whose design is optimized for durability. Of note is the presence of a metal foil 8 , such as titanium foil, that underlies the thin film metal electrode 2 . An adhesive 9 , such as B-stage acrylate adhesive, adheres the foil 2 to the underlying polymer layer 4 . A high tack-strength adhesive 10 adheres the polymer 4 to the stainless steel tube 6 .
[0017] FIG. 4 , a cross-section, shows the layers of a flexible sensing catheter whose design is optimized for durability. The layers are similar to those of FIG. 3 , except that the substrate tube 11 is made of a flexible polymer rather than a rigid material.
[0018] FIG. 5 (bottom panel) shows an array 12 that consists of sixteen tri-electrodes prior to their separation and individualization. FIG. 5 (top panel) shows the distal part of one tri-electrode after it has been individualized and adhered to the outer wall of a rigid tube 13 . In order to provide increased sensing accuracy by use of redundant signal collection, there are three indicating electrodes (distal electrode 14 , middle electrode 15 and proximal electrode 16 ). The reference electrode 17 interdigitates with the indicating electrodes. The interconnect traces of the indicating and reference electrodes 18 travel proximally and terminate in contact pads (not shown), which serve to electrically connect all electrodes with a body worn electronic unit.
DETAILED DESCRIPTION
[0019] In addition to durability, the cost of construction is important. The mass of the expensive indicating electrode metal (e.g. platinum, gold or carbon) must be minimized in order to yield a commercially viable solution. Thus, a thin film is favored for the choice of the indicating electrode. Because the underlying metal foil is thicker (greater mass), it must be a low cost material. Although one could directly laminate a thick platinum foil to the polymer, the cost of such a platinum-rich device would be prohibitive for a commercially viable disposable medical device. We discovered that the use of inexpensive titanium foil as an interfacial layer between the polymer and the electrode thin film serves as a low cost solution to the problem of fragility that was observed without use of a foil. In sensing catheters removed from active pigs, we observed very good mechanical integrity when titanium foil was utilized. More specifically, there was no metal fragmentation and no separation at the following interfaces: (1) the junction of the platinum or silver electrodes and the underlying titanium foil, (2) the junction of the titanium foil and the underlying B-stage acrylate adhesive, and (3) the junction of the acrylate adhesive and the underlying polyimide substrate.
[0020] All layers of the sensing catheter must be tightly adhered to the adjoining layers. One method of creating interfaces with good adhesion and good durability is the use a laminating press. To laminate the foil (e.g. titanium) to the underlying polyimide polymer, one can use a hydraulic press set to a high temperature (for example, 375 deg F.) and high pressure (for example, 235 PSI). A high tack adhesive such as B-stage acrylate is located at the interface of the foil and polymer and adheres the two materials together. After the lamination, thin film electrode materials can be deposited over the durable metal foil. The thickness of the metal foil is typically 2-15 μm.
[0021] The specific nature of how different materials interact with one another is pertinent to this invention. For example, despite the fact that the internal cohesion of the platinum and silver thin film is poor, both films adhere tightly to the underlying foil layer because of the high degree of similarity in the mechanical properties of the two metal layers. This adhesion was found to be far superior to that of adhesion to any polymer layer tested. Furthermore, the cohesion within the metal layer of the foil itself prevents it from breaking down into small fragments, a fate to which thin films quickly succumb under stress. This offers the benefit of cooperativity, i.e., removal of any small element of foil from the surface of the polymer requires the breaking of the bond formed by the entire surface area of the foil. This property stands in contrast to the removal of fragments of a thin film, which require much lower forces due to the smaller surface area of the fragments. The adhesion of the metallic foil to the polymer below is also improved dramatically in comparison to a thin-film/polymer adhesion.
[0022] The metal of which the foil is composed must be chosen carefully. In the case of an amperometric glucose sensor, the indicating electrode is typically platinum, gold or carbon. Copper (which is commonly used as the foil for flexible electronic circuits), is not suitable for use in a biosensor. Specifically, if there is concurrent physical contact between interstitial fluid, copper and platinum, a large galvanic current will occur as a result of a dissimilar metal junction. An ideal candidate for the foil is titanium, which is inexpensive and which we found to cause little to no galvanic current when paired with platinum. Silver and copper are not suitable as this foil material. Gold is of intermediate value.
EXAMPLE 1
Step 1
Laminate Metal Foil to Polymer Substrate
Purpose
[0023] This step creates a laminate of titanium and polyimide (Ti/Pi). In this example, the Ti thickness is 5 μm and the polyimide thickness is 12.5 μm, though these dimensions should not be construed as limiting. This example creates a laminate rectangle whose dimensions are 60 mm×85 mm.
Equipment
[0000]
Heated hydraulic press capable of achieving 400 deg F.;
Materials
[0000]
DI water; Polyimide sheet w/b-stage acrylate adhesive; Titanium foil; press pads; and graphite press plates.
Plate Setup Process
[0000]
Between the caul plates of the hydraulic press, materials should be stacked in the following order, from bottom to top: Graphite press plate; press pad; Titanium foil; Polyimide, with b-stage adhesive facing titanium foil; press pad; Graphite press plate.
[0027] Prepare graphite plate, graphite foil, and Teflon sheets prior to handling polyimide and titanium. All sheets should be cut to the size of the caul plates and cleaned with IPA, followed by careful inspection for lint or contaminants. If any portion cannot be cleaned properly it should be discarded and replaced.
[0028] Set titanium on a Teflon sheet atop graphite plate/foil. Inspect for lint or contaminants. Never apply any chemical to the b-stage adhesive, it should only be cleaned using bottled gas, clean compressed air, or a non-linting wipe.
[0029] Set polyimide sheet, with its plastic release layer (if present) removed, on top of titanium foil, b-stage adhesive facing downward. Look through the polyimide for any particles which may be lodged between sheets. If any appear, remove the polyimide and clean both sheets.
Press Operation
Place plate stack into hydraulic press and apply 5000 lb of force to caul plates. Set temperature setting to 375 deg F. for both top and bottom plates.
[0030] Once both caul plates reach 375 deg F., set press to 15000 lb and leave in place for 1 hour. Turn off heaters and allow caul plates to cool to under 100 F, then remove plate stack from press. Regions that are visibly wrinkled or that have contaminants are not suitable for sensor production.
General Equipment and Supplies (for All Following Steps)
[0031] Double-sided polyimide tape; plastic card; razor blade; 50×75 mm glass slide; isopropyl alcohol (IPA); deionized (DI) water; Pt (platinum) target; Ag (silver) target; aluminum foil; Ar plasma etcher; quartz crystal microbalance (QCM); sputter tool; hot plate; mask aligner—e.g OAI 200 tabletop mask aligner; spin coater capable of 300 RPM; argon source.
Step 3
Prepare Ti/Pi Laminate for Application of Pt and Ag Electrodes
[0032] Clean glass slide using soap and tap water, IPA wash, DI rinse, Ar plasma clean for 1 minute. Blow dry with clean air, argon, or nitrogen gas. Place sheet of aluminum foil on cutting board for use as workspace. Cut a 60 mm×85 mm rectangle of polyimide tape to allow for misalignment. Slowly apply double-sided polyimide tape onto the glass, ironing bubbles out using the plastic card as it is applied. Cut excess tape from slide, being sure to leave no exposed glass around the edges to accommodate the entirety of the pattern. Cut out a slightly oversized piece of Ti/PI laminate and iron on the laminate to the slide using plastic card. Discard if laminate is creased.
Step 4
Deposition of Silver Film
Purpose
[0033] To deposit a layer of Ag (later chloridized to Ag/AgCl) in order to create reference electrode. Nominal thickness is 400 nm, to allow for a reasonable thickness of Ag/AgCl after chloridization (chloridization reduces the thickness of Ag). In this process, silver sputtering is used, but other methods such as thermal evaporation, printing, or electroplating can also be used.
Specific Materials
Treated 50×75 mm Ti/PI sheet on glass slide, CRC-100 sputter unit, Ag target.
Method
[0034] Cut two small tabs of double-sided tape and place them on the bottom of the substrate to prevent it from sliding due to pump vibration or gusts of air when the roughing pump is turned on. Place substrate in CRC-100 unit, turn on pumps. Leave system to pump down for 15 minutes. This degasses any exposed polyimide/adhesive and improves vacuum quality. Sputter until Quartz Crystal Microbalance (QCM) reading is 5.00 kA (500 nm) of Ag. (Gain=75, Density=10.5, Z-ratio=0.529, Tooling Factor=256). Remove from CRC-100 unit, being exceedingly careful to not contact the silver coating. Silver thin films are extremely prone to scratching and should never be scrubbed. If cleaning must occur, proceed with a first-surface optics cleaning process. Tape test in a corner with 3M Magic Scotch tape to ensure good adhesion. Store in a dust-free covered container.
Step 5
Ag Patterning and Etch (Remove Unwanted Ag)
[0035] Purpose—To pattern photoresist for Ag pads on Ti/PI substrate.
Specific Materials
[0036] 50×75 mm Silver sputtered Ti/PI substrate on glass slide; NaOH pellets; 300 mL beaker; 250 mL beaker; optical mask, S1813 (photoresist); 80/20 HDMS primer.
Materials and Equipment (for Cleanroom Use)
[0037] Mask aligner; Spinner; hotplate; DI water; scale; S1800 series photoresist; NaOH (pellets or solution).
Method
[0038] Carry out photoresist process that is included at the end of this document.
[0039] Mix Ag etch solution. Add 75 mL of 3% USP grade H202, then 8 mL laboratory grade 30% Ammonium Hydroxide to a crystallizing dish. Immerse patterned substrate in solution for 30 seconds, gently agitating. Bubbles will not form when the reaction is complete. It is important to note that it is exceedingly critical that this etch completes. Rinse with DI water and blow dry with nitrogen gas or Argon. Remove photoresist with 0.3M NaOH solution.
Step 6
Pt Patterning, Sputtering, and Liftoff
Purpose
[0040] To pattern Pt pads on Ti/PI/Ag substrate.
Specific Materials
[0041] 50×75 mm Silver sputtered Ti/PI substrate on glass slide; NaOH pellets; 300 mL beaker; 250 mL beaker; optical mask; S1813 primer; Ti/PI/glass with Ag deposited on surface; 80/20 primer; Ag etch film mask; Borax; 3 mL pipette; Acetone; isopropyl alcohol (IPA); crystallizing dishes; graduated cylinder; timer.
Method
[0042] Carry out photoresist process that is included at the end of this document. Mark the mask name and revision on the traveler document. Protect using a cleanroom wipe or Kimwipe. Keeping the substrate dust-free is critical. Clean under Ar for 1 minute. Place into vacuum system, turn on pumps, allow to pump for 15 minutes. Sputter 90 nm (0.900 KA) Pt. (Gain=75, Density=10.5, Z-ratio=0.529, Tooling Factor=256). Use 3 strips of Scotch tape to cover the entirety of the substrate. Press down firmly across the entirety of the substrate, then slowly remove in order to remove platinum layer. Inspect tape-test sheet for any failures in Pt adhesion. Mark any failures in traveler, label and keep the test if failures are found. Use an additional piece of tape to remove any bridges between platinum pads. (These will have a different appearance than the pad themselves and are quite noticeable). Remove photoresist/remaining Pt by tape method (3m magic tape over entire array), then sonication in 0.5M NaOH. If any bridges remain, gently scrub using Kimwipe while in solution.
Step 7
Titanium Etch (Remove Unwanted Ti in Order to Create Electrical Interconnects)
Purpose
[0043] To define titanium traces on sensor.
Specific Materials
[0044] Ti/Pi mounted slide; titanium etchant; 400 mL beaker; crystallization dish; DI water; NaOH.
Equipment
[0045] Ultrasonic cleaner
Method
[0046] Carry out photoresist process that is included at the end of this document. Prepare etchant bath. Place substrate in etchant solution and observe closely, rinse with DI water when etch is complete.
[0047] Rinse with DI water and blow dry with nitrogen gas or argon.
Step 8
Prepare Sensors For Human Use
Individualize, Wrap, Chloridize, Apply Protective Coat to Reference Electrode, and Clean Indicating Electrodes
[0048] Apply 5 mil (0.005 inch) polyimide backer strip with adhesive to back side of the electrode array (back side is the side without electrodes). Then apply protective tape to photoresist-covered front side (for example, S2020 tape from Champion). Individualize the 3-electrode strip by use of an arbor press.
[0049] Wrap the strip around a 21-25 gauge stainless steel needle (sharp bevel on end) or blunt tube. Sensing strips are wrapped axially around the needle/tube and adhered using epoxy or other biocompatible adhesive. If a blunt tube can be used, a sharpened stylet within the tube is utilized in order to pierce the skin upon insertion. (The stylet is later removed, allowing drug delivery via the lumen of the tube).
[0050] Ferric chloridize with 50 mM FeCl 3 for 3 min. ALTERNATIVE: Electrochloridize at 0.6 V×10 min using power supply configures so that the Ag is the Anode (+) and Pt is the cathode (−). Bath for electrochloridization is KCl and HCl, both 0.5 M.
[0051] Coat reference electrode with 5% polyurethane in 95%-5% THF-DMAC; dry×20 min at 40 deg C.
[0052] Voltage cycle (clean) indicating electrodes in 1×PBS, −1.5 volts×5 min, 1.5 volts×5 min, −1.5 volts×5 min.
Apply Enzyme Layer and Outer Membrane
[0053] Drop cast with glucose oxidase (GOX), bovine serum albumin (or human serum albumin) and glutaraldehyde in weight ratio of 6:4:5 or 6:4:1; then dry for 10 or more min at 40° C. NOTE: The purpose of the glutaraldehyde is to crosslink and immobilize the enzyme/albumin. Deposit additional GOX layers as desired, for example, four more times (5 total coats). Dry all but final coat for 10 min and final coat for 20 min. Then rinse in stirred DIW for 10-15 minutes. Use Kimwipe to remove GOX flaps/strings that are not well-adhered. Coat twice with 1.5-2.5% w/v polyurethane (PU) on the IE (indicating electrodes). Alternatively use a PU that includes silicone and/or polyethylene oxide moieties in order to regulate oxygen and glucose permeation, respectively. Solvent: 95-5 THF-DMAC. Dry each PU coat×20 min at 40 deg C. Keep solvent and polymer/solvent dry with molecular sieves 3A or 4A.
Assemble
[0054] Insert the sensing catheter into a battery powered telemetry module (low energy Bluetooth module such as that marketed by Nordic, Inc).
Sterilize
[0055] Expose to e-beam, gamma irradiation, ethylene oxide or activated glutaraldehyde sterilizing solution.
Attach to Insulin Pump and Operate Device
[0056] After priming with insulin, an infusion line from an insulin pump (e.g. Medtronic Minimed, Animas Ping, Tandem t-slim, Roche Spirit, etc) is attached to the sensing catheter (which is located in subcutaneous tissue) and insulin is delivered. The constant pressure head from the fluid infusion line prevents fluids from coming back out of the body. In order to be displayed to the user, the glucose concentration or the electrical current or voltage data representing glucose concentration is obtained from the sensor. These data are transmitted by Bluetooth or other wireless protocol to the display of the insulin pump, to a computer, to a dedicated medical device, or to a cell phone. Storage of data can be carried out on any of these devices or on the body worn electronics unit that directly interfaces with the subcutaneous sensing catheter. An advantage of storing the glucose data on the body-worn unit is that the data are not lost if the receiving unit is lost or out of range.
Appendix
Photoresist Process (Common to Multiple Steps)
Materials
[0057] 50×75 mm Ti/PI substrate on glass slide; NaOH pellets or solution; 300 mL beaker; 250 mL beaker; optical mask; photoresist.
Method
[0058] Mix 200 ml 0.15M NaOH (8 g/L w/pellets or 15 mL/L w/10M solution) primary developer in glass dish. Ensure that solution is well mixed, especially if using NaOH pellets. Use bath for no more than 2 developments. Mix 0.075M NaOH secondary rinse in glass dish. Ensure that solution is well mixed. Spin coat two layers of photoresist. Develop in 0.15M NaOH developer, gently agitating. Rinse in secondary bath for 10 seconds. Dry with nitrogen gas, inspect for developed regions with remaining resist. (Exposed regions should appear uniform across the entirety of the substrate. Properly cleaned regions will gain a faintly white appearance as they go from wet to try if no photoresist remains on the surface). If regions remain, immerse in primary and secondary baths for an additional 5 seconds and check again. If substantial regions remain, air dry, clean with 0.3M NaOH, and return to step 4. Check process parameters. Bake for 60 seconds as above and allow to cool.
CITED REFERENCES (ATTACHED)
[0059] 1. Alzoubi K, Lu S, Poliks M. Experimental and Analytical Studies on the High Cycle Fatigue of Thin Film Metal on PET Substrate for Flexible Electronics Applications. IEEE Transactions on Components, Packaging, and Manufacturing Technology. 2011; Vol 2.
[0060] 2. Dai C, Zhang R, Yan C. Size effects on tensile and fatigue behaviour of polycrystalline metal foils at the micrometer scale. Philosophical Magazine. 2011; 91:932-45.
[0061] 3. Lavvafi H, Lewandowski J R, Lewandowski J J. Flex bending fatigue testing of wires, foils and ribbons. Materials Sci and Engineering 2014; 1:123-30. | This invention pertains to the concept of creating a strip that contains one or more amperometric biosensing electrodes and integrating this strip into the outer wall of a hollow catheter (cannula). The electrodes can be used for continuous sensing of an analyte such as glucose and the hollow lumen can be used concurrently for delivery of a drug such as insulin. There is a risk for electrode films to break apart during impact. However, if there is a metallic foil beneath (underlying) the thin film metal electrodes, durability and fatigue resistance are markedly improved. The term “foil” indicates a metal layer that is 2-15 μm in thickness. Foils can be created by rolling, hammering, electroplating, printing, or vacuum-deposition. A foil-polymer laminate is suitable as a substrate because it permits low-cost patterning and assembly into a durable, fatigue-resistant sensor. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to a method and a device for manufacturing a shaped article by sonoerosion.
More specifically, the invention relates to the manufacture of a ceramic artificial tooth made of a pre-fabricated shaft part which is to be implanted in the jaw, and an individually shaped tooth superstructure to be mounted on the implanted shaft part. The superstructure has a locking portion provided in a part of its surface for engagement with a standardized counter-locking portion provided on the implanted shaft part. The locking portion of the superstructure is usually in the form of a recess, and the counter-locking portion on the shaft part is formed as a projection complementary formed with respect to the recess for snug fitting therein. By using locking and counter-locking portions of a non-circular, specifically polygonal, cross-section, accurate alignment between the axis of the shaft part and that of the superstructure and accurate mutual angular orientation about the aligned axes is achieved.
Conventionally, tooth superstructures are cast from metallic materials. It would be desirable to make them of hard ceramics. U.S. Pat. No. 3,971,133 and, similarly, published German Patent Applications 3,928,684 and 4,342,078 describe methods for making ceramic dental restoration parts by sonoerosion. The known restoration parts, however, are bridges and crowns to be mounted on tooth stumps individually prepared to receive the respective bridge or crown. There is no fitting to a pre-fabricated locking portion.
Conventional sonoerosive methods are unsuited for manufacturing such tooth superstructures as referred to above, which require a precisely fitting interlocking with a standardized shaft part. This is because sonotrodes are subject to considerable wear so that the working precision decreases with progressing penetration of the tool into the workpiece material.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method and an apparatus for manufacturing a shaped article which has a locking portion in its surface for engagement with a standardized counter-locking portion, but is otherwise individually shaped, with a high precision fitting between the locking and counter-locking portions.
A more specific object of the invention is to manufacture an individually shaped superstructure of an artificial tooth which has a standardized locking portion for exactly fitting engagement with a standardized counter-locking portion provided on a pre-fabricated shaft part to be implanted in the jaw of a patient.
According to the present invention, a shaped article which has in part of its surface a locking portion for positive engagement with a counter-locking portion of a pre-fabricated structural part, with the remaining surface of the shaped article being individually shaped, is manufactured by using a standardized sonotrode for working the locking portion and at least one individually formed sonotrode for working the remaining surface.
The fact that a pre-fabricated sonotrode is used for producing the locking portion results in a substantially more accurate shaping of that portion than would be possible by the use of an individually formed sonotrode, such as is prepared by a dental laboratory technician prepares taking an impression of the patient's jaw and performing a number of intermediate molding steps to arrive at the final sonotrode. Each such impression and molding step is subject to certain tolerances, inaccuracies and imaging errors. While the addition of such errors may be tolerated as regards the outer shape of the tooth superstructure, it would cause unacceptable deviations in position and orientation if permitted at the locking portion.
Moreover, the active working part of a sonotrode may be made with considerably higher accuracy by automatic machine tools and high-precision measuring devices.
Also, prefabricated sonotrodes may be provided with a well-defined amount of oversizing to compensate any wear that occurs during working. Similarly, certain faces of the sonotrode may be intentionally undersized to compensate any gap caused by an abrasive used for the work.
In manufacturing a tooth superstructure having a locking portion, it has turned out proper first to work the locking section with the pre-fabricated sonotrode and subsequently work the remaining surface of the superstructure with the individually formed sonotrode. Alternatively, the two manufacturing steps may be interchanged.
While the invention is particularly useful in making artificial teeth or dental restoration parts, it is likewise applicable for a highly precise formation of slides, through-bores or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross-sectional view of a lower jaw with an implanted artificial tooth and a natural tooth;
FIG. 2 illustrates part of a sonoerosion apparatus in a first step of manufacturing the artificial tooth shown in FIG. 1;
FIGS. 3 and 4 show the apparatus of FIG. 2 in second and third manufacturing steps, respectively;
FIGS. 5(a) and 5(b) are an end view and a side view illustrating a locking structure for an artificial tooth; and
FIG. 6 is a side view, partly in section, of a crowned tooth.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In the following description, the invention will be explained by reference to the field of dental restoration. The invention is not limited to this field but may be used in a variety of other technical areas
FIG. 1 is a schematic partial view of a lower jaw 10 with an artificial tooth 12 next to a natural tooth 14. The artificial tooth 12 is made of an implanted shaft part 16 and a head part or superstructure 18 mounted on the shaft 16 and shaped in accordance with the upper part of the natural tooth which it replaces.
The shaft 16 is substantially cylindrical with outer cylindrical surface suitably structured to facilitate anchoring in the jaw 10. In FIG. 1, the surface structure is shown as that of a thread; other shapes and structures with recesses and projections may be used alternatively.
The shaft 16 has an axial bore 20 open to the upper surface, which extends above the jaw 10, and provided with an internal thread for receiving a fixing screw (not shown) which penetrates a through bore 22 provided in the superstructure 18. By tightening the screw, the superstructure 18 is fixed to the implanted shaft 16. The head of the fixing screw may be covered by a suitable dental cement.
With a two-part artificial tooth of this type, it is important for the superstructure 18 to be positioned and oriented with respect to the implanted shaft 16 exactly in the way designed by the dental laboratory technician. To this end, positively interlocking means are provided on the shaft 16 and superstructure 18 to prevent angular deviations in the longitudinal and circumferential directions with respect to the axis of the fixing screw.
The interlocking means include a projection 24 formed on the free end surface of the shaft 16 and a complimentarily shaped recess 26 formed in the lower surface of the superstructure 18. The peripheral surface of the projection 24 may be that of a prism with a triangular, rectangular, hexagonal, octagonal or, generally, n-angular cross section. Alternatively, it may be substantially cylindrical with a cross section that is not completely circular, for instance that of a flattened circle.
In cases where only misalignment between the axis of the through bore 22 in the superstructure 18 and the axis of the threaded bore 20 in the shaft 16 is to be prevented but rotation about these axis is permitted, a completely circular-cylindrical outer surface of the projection 24, and thus of the inner surface of the recess 26, may be used.
The following is a description of a method for manufacturing the artificial tooth 12.
After the tooth to be replaced, or the remainders thereof, has been removed and the jaw 10 exposed, the shaft 16 is implanted. Thereafter, usually after the wound has healed and the projection 24 of the shaft 16 has been exposed by surgery, an impression of the part of the jaw 10 including and surrounding the implanted shaft 16 is taken by conventional means. At this time, a dummy pin (not shown) is inserted in the threaded bore 20, which projects beyond the free surface of the implanted shaft 16. The pin extends through a sleeve (not shown) which is provided with a fitting surface for precise engagement with the projection 24.
The impression is then used to produce a positive model of gypsum or another suitable molding material which in the bottom surface of the gap to be filled by the artificial tooth has a replica of the shaft projection 24. The positive model is also provided with a cylindrical replica of the shaft 16 by filling the recess of the impression with gypsum and is positioned on the positive model of the projection 24, by means of the pin fixed in the negative model, in the same longitudinal and peripheral orientation as the shaft 16 in the jaw 10.
The technician subsequently forms, from synthetic material, a model of the superstructure, i.e. of the artificial tooth to be manufactured or of part thereof surrounding the exposed surface, particularly the projection, of the shaft model.
Upon removal and curing of the superstructure model, two sonotrodes for finishing the superstructure from two opposite sides thereof are prepared. To this end, the later working axis is defined in alignment with the axis of the pin used in taking the original impression. The positive model of the superstructure is placed on an alignment part which has the shape of the shaft projection 24 with the pin inserted in the threaded bore 20. The alignment of the working axis with the axis of the pin must be as precise as possible.
The equatorial plane of the superstructure is then determined with respect to the working axis. By conventional techniques, such as described in the above prior-art documents, the sonotrode for working the occlusal surface side of the superstructure is now prepared. Subsequently and also in accordance with conventional techniques, the counter sonotrode for working the surface of the artificial tooth from the side facing the jaw is prepared.
The manufacturing process proper for making the superstructure 18 will now be explained in more detail with reference to FIGS. 2 to 4.
As shown in FIG. 2, a workpiece (blank) 28 of suitable size, preferably a non-worked ceramic block somewhat larger than the superstructure to be manufactured, is first worked with a pin sonotrode 30 for forming the through bore 22 (see FIG. 1) for the fixing screw that will eventually engage the threaded bore 20 of the shaft 16.
For simplifying the representation in FIGS. 2 to 4, the ultrasonic generator coupled to the respective sonotrode and associated guides and holders are not shown with the exception of part of a chuck 32 for the workpiece 28.
The pin sonotrode 30 includes a sonotrode shaft 34 to be coupled with the ultrasonic generator and a cylindrical working shaft 36 which has a diameter slightly larger than the fixing screw. The pin sonotrode 30 is advanced toward the workpiece 28 to the depth of the through bore 22 to be provided in the finished superstructure 18.
The pin sonotrode 30 is then replaced by a fitting sonotrode 38 shown in FIG. 3. The fitting sonotrode 38 is not individually made but pre-fabricated. It includes a sonotrode shaft 34 and a working portion 40 which has the same profile as the locking pojection 24 of the shaft 16. The working portion 40 carries a centering projection 42 which fits into the through bore 22 formed in the workpiece 28 to ensure the fitting sonotrode 38 to be advanced in proper alignment with the workpiece 28 in forming the locking recess 26 therein. The centering projection has proved useful in practice but is not always necessary.
During this working step, the fitting sonotrode 38, particularly the working portion 40 thereof, are subject to wear. With proper dimensioning of the working portion 40, such wear is compensated by the gap-caused by the abrasive used, so that a locking recess 26 exactly complementary to the locking projection 24 of the shaft can be formed.
Subsequently, the fitting sonotrode 38 is replaced by a shaping sonotrode 44 shown in FIG. 4 which is used to prepare the surface of the superstructure facing the jaw. This shaping sonotrode 44 includes a model 41 of the locking projection 24 of the shaft 16 and a centering projection 46 which has the same task as the centering projection 42 of the fitting sonotrode 38. The shaping sonotrode 44 has a cup-shaped wall portion 48 the inner surface 50 of which is a negative of the surface portion of the superstructure model prepared by the technician.
To ensure precise alignment and angular orientation of the shaping sonotrode 44 with respect to the workpiece 28, an adapter 52 is used, which is a cylindrical part having one end provided with a recess 54 for receiving the projection 41 formed in the shaping sonotrode 44, and its other end provided with a projection 56 for engaging the locking recess 26 formed in the workpiece 28. Upon proper alignment and orientation, the adapter 52 is removed, and the shaping sonotrode 44 is advanced toward the workpiece 28 and ultrasonically vibrated to shape the outer surface of the workpiece 28 surrounding the locking recess 26.
In working the workpiece 28 with the inner surface 50 of the shaping sonotrode 44, the projection 41 will enter the locking recess 26 previously formed in the workpiece 28. The locking recess 26 is preferably not worked by the projection 41, although some amount of working may take place depending on the precision by which the projection 41 is formed in the shaping sonotrode 44.
To take account of the working gap in this sonoerosive working, it has proved advantageous to use the same abrasive slurry for working the workpiece 28 with both the fitting sonotrode 38 and the shaping sonotrode 44.
It is possible to subdivide the step of working the workpiece 28 by means of a shaping sonotrode into two or more partial steps. Also, two identical shaping sonotrodes may be used to produce the desired shape of the workpiece by subsequent coarse and fine working. For the fine working, a new shaping sonotrode 44 is employed in the final finishing step of preparing the surface of the superstructure 18 at the side facing the jaw. Further, the fine working step may be followed by other conventional finishing steps.
Subsequently, the occlusal surface part of the workpiece 28 is worked with a counter sonotrode (not shown). To this end, the unit formed by the workpiece 28 and the shaping sonotrode 44 engaging it is separated from the ultrasonic generator and mounted on the chuck 32, while the counter sonotrode is coupled to the ultrasonic generator and aligned with respect to the first shaping sonotrode 44. The workpiece 28 is then worked at its occlusal side to prepare the final superstructure.
In another embodiment of the working method according to the invention, the locking recess 26 may first be coarse-worked by means of the individually prepared shaping sonotrode 44 and thereafter, in a second method step, finished with the pre-fabricated fitting sonotrode 38. In this embodiment, the working step illustrated in FIG. 4 would be performed prior to that shown in FIG. 3. In this case, the projection 56 provided on the adapter 52 must be dimensioned somewhat smaller than the projection 41 in the shaping sonotrode 44, which will work the locking recess 26 to its final shape.
Pre-fabricated shafts 26 are available on the market in different sizes to fit different jaws. The size of the locking projection 24 is correspondingly variable. Therefore, an according set of differently sized fitting sonotrodes 38 and adapters 54 should be available.
FIGS. 5(a) and 5(b) show a top view and a side view of a natural tooth 60 with a joining portion 62 prepared in accordance with the invention. The joining portion 62 has a dove-tail shape and serves to receive a corresponding sliding element of an artificial tooth or bridge part (not shown).
FIG. 6 shows a side view, partly in section, of a crown 64 fixed to a tooth stump 68 by means of pins 66. The connecting pins 66 are fixed in the crown 64 by means of glass solder 70 or the like. In this case, the through bores 72 in the crown 64 for the fixing pins 66 are prepared by sonoerosion in accordance with the present invention to achieve precise alignment of the bores 72. | A shaped article, specifically an artificial tooth, is made of two parts. individually shaped first part 18, specifically the head part or superstructure of the artificial tooth, has a standardized locking portion 26 for engagement with a standardized counter-locking portion 24 provided on a pre-fabricated second part 16, specifically the shaft part of the tooth to be implanted in a patient's jaw. The individually shaped part 18 is manufactured by using a pre-fabricated sonotrode 38 for producing the configuration of the locking portion 26 and one or more individually produced shaping sonotrodes 44 are used for generating the parts of the surface other than the locking portion 26. This permits the individually shaped part to be produced in an economic way yet with high precision of the locking portion. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a noise attenuator for attenuating noises generated from a compressor of a refrigerator, an air conditioner or the like, and more particularly to a noise attenuator of a compressor for attenuating noises generated from valves disposed within the compressor.
2. Description of the Prior Art
Generally, a compressor is constructed to comprise a driving unit and a compressing unit sealed in an airtight case 1, as illustrated in FIG. 1.
The driving unit comprises a motor, which in turn, is composed of a rotor 2 and a stator 3.
The rotor 2 is equipped with a rotary shaft 6.
The compressing unit comprises: a crank shaft 5 eccentrically jointed to a lower end of the rotary shaft 6 of the driving unit; a connecting rod 9 for transforming a rotary movement of the crank shaft to a reciprocating motion by being rotatively jointed to the crank shaft 5; a piston 7 for performing a reciprocating motion by being rotatively jointed to the connecting rod 9; a cylinder 8 for receiving the piston 7; and a head cover 4 jointed to one side of the cylinder 8.
Meanwhile, a noise attenuator 10 is disposed on an upper side of the cylinder 8 in order to attenuate noises generated from the cylinder 8.
The noise attenuator 10 is connected to a suction pipe 12 which is, in turn, connected to an accumulator (not shown).
The reciprocating compressor thus constructed, mainly being installed on a refrigerator, air conditioner or the like, sucks in refrigerant gas to compress the same for discharge thereafter, and when the rotor 2 is rotated by power supplied to the motor comprising the stator 2 and the rotor 3, the rotary shaft 6 is rotated in accordance with the rotation of the rotor 2.
As the rotary shaft 6 is rotated, so is the crank shaft 5 rotated, and when the crank shaft 5 is rotated, the connecting rod 9 begins a linear reciprocating motion.
When the connecting rod 9 starts the linear reciprocating motion, the piston 7 reciprocatively moves within the cylinder 8.
In other words, the piston performs an intake stroke for intaking the refrigerant gas into the cylinder 8 and a discharge stroke for compressing the refrigerant gas sucked into the cylinder 8 to thereafter discharge the same.
During the intake stroke, the refrigerant gas infused through the accumulator is sucked into the cylinder 8 through the intake pipe 12 and the noise attenuator 10.
The refrigerant gas sucked into the cylinder 8 is compressed by the piston 7 in high temperature and high pressure and is discharged outside of the cylinder 8 to thereby be supplied to a condenser (not shown).
In other words, the refrigerant gas is infused into the cylinder 8 through the head cover 4 disposed at one side of the cylinder 8 and through a suction valve (not shown) during the intake stroke, and the refrigerant gas, after being compressed in high temperature and high pressure, is discharged to the condenser (not shown) through a discharge valve (not shown) and the head cover 4 disposed at one side of the cylinder 8 during the discharge stroke.
As seen from the aforesaid, the noise generated by the closing and opening of the suction valve and the discharge valve during the intake and discharge strokes, and the noise is attenuated by the noise attenuator 10.
FIG. 2 is a sectional view for illustrating construction of a conventional noise attenuator 10.
According to FIG. 2, the conventional attenuator 10 comprises: an external case 11 having an inner space; a separation member 14 for partitioning the inner space into an upper chamber 13a and a lower chamber 13b; a suction hole or part 15 for interconnecting the suction pipe 12 (see FIG. 1) and the upper chamber 13a to thereby let the refrigerant gas to be infused into the upper chamber 13a from the suction pipe 12; a passage in the form of a connecting pipe 16 for piercing through the separation member 14 to thereby connect the upper chamber 13a and the lower chamber 13b; and passage in the form of infuse pipes 18a and 18b for supplying the refrigerant gas infused into the lower chamber 13b to the cylinder head 4 of a suction chamber 4a.
The reference numeral 4b designates a discharge chamber.
The noise attenuator 10 thus constructed is compelled to receives a noise generated by way of the closing and opening of the suction valve and the discharge valve disposed between the cylinder head 4 and the cylinder 8 (see FIG. 1), and the generated noise is attenuated in the course of passing through the infuse pipes 18a and 18b, lower chamber 13b, connecting pipe 106 and the upper chamber 13a which happens to have a cavity length of l.
At this time, the noise attenuator 10 has attenuated the noise as illustrated in solid lines in FIGS. 5 and 6.
According to each of FIGS. 5 and 6, the conventional noise attenuator 10 has shown a best noise transmission loss or reduction (the loss=inputted noise value-outputted noise value) at around 1,400 Hz.
Generally speaking, a higher transmission loss equates to a lower penetration efficiency of sound waves.
However, the noise generated by way of closing and opening of the suction valve and the discharge valve in the compressor is generally produced at around 500 Hz, which can hardly be attenuated by the noise attenuator 10 effectively.
In other words, as illustrated in FIGS. 5 and 6, the noise attenuator 10 has a transmission loss of less than 30 dB at around 500 Hz, and if it is assumed that the inputted noise value is 100 dB, the actual noise value transmitted to a user is a rather high noise of 70 dB.
As mentioned above, the conventional attenuator has a low transmission loss at around 500 Hz, so that the noise generated from the valves of the compressor is not only transmitted intact to the outside, but also the vibration resulting from the noise causes frequent inoperation, thereby causing degradation of the quality of the product.
SUMMARY OF THE INVENTION
The present invention has been disclosed to solve the aforementioned problems, and it is an object of the present invention to provide a noise attenuator of a compressor for attenuating noise having a predetermined range of frequency generated from valves of the compressor.
The object of the present invention is attained by a noise attenuator of a compressor which has a maximum value of transmission loss transmitted to a predetermined range by way of extending a cavity length of a first space, the noise attenuator comprising: a case member having an inner space; a separation member for partitioning the inner space of the case member into a first and a second space; and a refrigerant suction means for infusing refrigerant gas into a refrigerant compression means through the first and second space.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and aspects of the invention will become apparent from the following description of embodiments with reference to the accompanying in which:
FIG. 1 is a sectional view for illustrating an inner construction of a conventional compressor;
FIG. 2 is a cutaway view for illustrating construction of a conventional noise attenuator;
FIG. 3A, 3B and 3C are sectional views for illustrating embodiments of the noise attenuator in accordance with the present invention;
FIG. 4 a sectional view for illustrating other emdodiment of the noise attenuator in accordance with the present invention; and
FIG. 5 and 6 are graphs for illustrating transmission losses of the conventional noise attenuator and the noise attenuator in accordance with the present invention respectively.
DETAILED DESCRIPTION OF THE INVENTION
First Embodiment
FIG. 3A is a sectional view for illustrating a first embodiment of the noise attenuator in accordance with the present invention.
According to FIG. 3A, the noise attenuator 10 is partitioned into an upper chamber 40a and a lower chamber 40b by the separation member 30 in the inner space thereof.
At this time, the upper chamber 40a of the noise attenuator 10 includes a main or upper area 42 and a branch line in the form of a lateral area 44 (a lateral area opposite from a suction hole 15) branching from a downstream end of the upper area 42 and extending perpendicular thereto.
The cavity length L of the upper chamber 40a is L1+L2, where L1 is a distance from a center of the connecting pipe 16 for connecting the upper chamber 40a and the lower chamber 40b to a center of the lateral area 44 and L2 is a distance from a center of the upper area 42 to a lowest end of the lateral area 44.
An exit orifice 50 is formed on the lowest end of the upper chamber 40a, i.e., on the lowest end of the lateral area 44.
The exit orifice 50 enables oil collected in the upper chamber 40a to be retrieved.
Meanwhile, one end of the upper chamber 40a is disposed with the suction hole 15.
Therefore, the refrigerant gas is infused into the upper chamber 40a through the suction hole 15. The refrigerant gas infused into the upper chamber 40a passes through the separation member 30 and is infused to the lower chamber 40b through the connecting pipe 16 for connecting the upper chamber 40a and the lower chamber 40b.
The refrigerant gas in the lower chamber 40b is infused into a suction chamber 4a of the cylinder head 4 through the infuse pipes 18a and 18b.
The reference numeral 4b is a discharge chamber.
The operation and effect of the first embodiment thus constructed according to the present invention will be described, referring to the accompanying drawings.
First of all, the refrigerant gas in the suction chamber 4a is infused into the cylinder 8 (see FIG. 1) in accordance with the movement of the piston 7 during the intake stroke.
When the gas is infused into the cylinder 8 as mentioned above, the refrigerant is infused into the upper chamber 40a from an evaporator (not shown) through the suction hole 15, as per the arrow direction illustrated in FIG. 3A.
The refrigerant gas infused into the upper chamber 40a flows into the lower chamber 40b through the connecting pipe 16.
The refrigerant gas in the lower chamber 40b is infused into the suction chamber 4a of the cylinder head 4 through the infuse pipes 18a and 18b.
The refrigerant gas infused into the suction chamber 4a flows into the cylinder 8 through a suction valve (not shown).
Next, the refrigerant gas is compressed in the cylinder 8 by the piston 7 and is discharged to the outside of the cylinder 8 through the discharge valve (not shown).
At this time, the suction valve disposed on the cylinder head 4 is opened when the refrigerant gas is sucked into the cylinder 8 and is closed when the gas is compressed to thereby be discharged.
Furthermore, the discharge valve disposed on the cylinder head 4 is closed when the gas is sucked into the cylinder 8, and is opened when the gas is compressed to thereby be discharged, as against the suction valve.
Noise is generated as the valves are opened and closed as mentioned in the aforesaid, and the noise usually possesses 500 Hz of frequency.
The noise generated by the valves is transmitted in a direction opposite the direction of the refrigerant gas flow.
In other words, the noise generated from the valves of the cylinder head 4 is transmitted to the outside through the infuse pipes 18a and 18b, lower chamber 40b, connecting pipe 16, upper chamber 40a, suction hole 15 and the like.
At this time, as seen from the foregoing, the noise of 500 Hz range generated from the valves is attenuated at the upper chamber 40a.
In other words, as seen from the following formula 1, the frequency fr where the transmission loss is peaked becomes lower as the cavity length L is lengthened, and the cavity length L of the upper chamber 40a is made to be L1+L2 as mentioned above, so that the peak attenuation of noise occurs at 500 Hz. ##EQU1## (where, C is speed of sound in refrigerant and n=any whole number such as 0, 1, 2, · · ·.)
Accordingly, let's assume that the frequency fr where the transmission loss is peaked is 500 Hz, then, the cavity length L of the upper chamber 40a according to Formula 1 is 75 mm. ##EQU2## (where, inner temperature of the noise attenuator is 34 degrees celsius and the speed of sound C in the refrigerant is given 150 m/sec.)
As mentioned above if the cavity length L of the upper chamber 40a is lengthened, the transmission loss can be given as illustrated in dotted lines at FIG. 5.
In other words, the transmission loss at 500 Hz range as illustrated in FIG. 5 is 60 dB, which is considerably high.
If the noise value transmitted to the upper chamber 40a is 100 dB, the noise value transmitted to a user, that is, outputted noise value, becomes 40 dB, which is low enough to give only minimum damage to the user. Thus, in contrast to the prior art, the cavity length L of the chamber 40a is specifically dimensioned as a function of the frequency of the compressor noise (i.e., is dimensioned in accordance with Formula 1, above) to provide an optimum noise attenuation. By configuring the chamber 40a as having non-colinear portions 42, 44, rather than as a single, long linear portion, the size of the attenuator can be kept within desired limits while still providing the requisite cavity length L.
Second Embodiment
FIG. 3B is a sectional view of a second embodiment for a noise attenuator according to the present invention.
In the second embodiment, same reference numerals are given to the parts having identical functions as those in the first embodiment.
The difference between the first embodiment and the second embodiment illustrated in FIG. 3B is that in the second embodiment the branch line is in the form of a lateral area 46 located adjacent to the suction hole 15.
Accordingly, the cavity length L of the upper chamber 40a in the second embodiment also becomes L1+L2, thus functioning in the same manner as in the first embodiment.
Third Embodiment
FIG. 3C is a sectional view of a third embodiment of the noise attenuator according to the present invetnion.
In the third embodiment, same reference numerals are given to the parts having identical functions as those in the first embodiment.
The difference between the first embodiment and the third embodiment illustrated in FIG. 3C is that the branch line comprises a lateral area having outer and inner segments 48', 48", due to the presence of a rib member 60 projecting downwardly from the upper surface of the separation member 30.
In accordance with the above extensions, the upper chamber 40a comes to have two additional lateral areas 4', 48 of predetermined lengths l1 and l2, respectively.
At this time, summation the two additional lateral areas 1 and 2 becomes L2, which is the same as the extended cavity length L2 at the first or second embodiment, as shown in Formula 2.
l1+l2=L2 Formula 2
By way of example, let's assume that the frequency fr where the transmission loss is peaked is 500 Hz, then, the cavity length L becomes 75 mm, which now becomes a total length of L1+L2, in other words, L1+l1+l2.
Thererfore, even in the third embodiment, the cavity length L of the upper chamber 40a becomes L1+L2, which operates in the same manner as in the first embodiment.
Fourth Embodiment
FIG. 4 is a sectional view of a fourth embodiment for a noise attenuator in accordance with the present invention.
In the fourth embodiment, same reference numerals are given to the parts having identical functions as those in the first embodiment.
The difference between the first embodiment and the fourth embodiment illustated in FIG. 4 is that the branch line is in the form of an additional upper area 49 extending along and parallel to the upper surface of the main upper area 42, and communicates therewith via flow hole 70.
At this time, a cavity length L3 extended along the upper surface of the upper chamber 40a has the same length as the cavity length L2 extended along the lateral area of the upper chamber 40a.
Accordingly, the noise of 500 Hz range generated from the valves of the cylinder head 4 is attenuated by the cavity having a length L1+L2 formed along the upper and lateral areas 42, 44 and by the cavity having a length L1+L3 formed along the upper surface of the upper chamber 40a.
As seen in FIG. 4, the noise attenuator described in the fourth embodiment according to the present invention has a transmission loss as illustrated in dotted lines at FIG. 6.
According to FIG. 6, because the transmission loss at 500 HZ is 80 dB, and if it is assumed that the noise value inputted to the upper chamber 40a is 100 dB as in the first embodiment, the noise passing through the suction hole 15 becomes 20 dB, which is markedly low to the user.
As seen from the foregoing, the noise attenuator of a compressor according to the present invention provides an effective apparatus for use in a compressor by attenuating further the noise of 500 Hz range generated from the compressor.
The foregoing description and drawings are illustrative and are not to be taken as limiting. Still other variations and modifications are possible without departing from the spirit and scope of the present invention.
In other words, it should be apparent that the cavities can be extended to both sides of the lower chamber by a predetermined length L2 respectively, two cavities can be extended to either one side of the upper chamber by a predetermined length L2 respectively or the cavities can be extended to the upper surface of the upper chamber by a predetermined length L2. | A noise attenuator for a refrigerant-circulating compressor includes a casing whose interior space is divided into first and second chambers. The first chamber has an inlet for receiving refrigerant and is connected by a conduit with the second chamber. Additional conduits connect the second chamber with the compressor inlet. The cavity length L of the first chamber is determined as a function of a compressor noise to be attenuated, using the formula fr=C/4L (2n+1), where fr is the frequency of the noise, C is the speed of sound in refrigerant, and n is any whole integer (including zero). The first chamber may comprise a first portion and a second portion in the form of a branch line, with the cavity length L being defined by a combination of both of the portions. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Pursuant to 35 U.S.C. section 119(e), the present invention claims the benefit of the filing date of U.S. provisional application 60/767120 filed 4 Mar. 2006, the text of which is included by reference herein.
FIELD OF INVENTION
[0002] In the field of hydrocarbon extraction from in-ground oil sands or similar deposits, a device and method of using the device for the extraction of the hydrocarbons.
BACKGROUND OF THE INVENTION
[0003] The invention is termed “IXOS,” an acronym of sorts derived from In-Situ Extraction of Hydrocarbons from Oil Sands.” IXOS employs an electric current between porous, tubular in-ground electrodes to flow hydrocarbons in a deposit into the electrode. Electric resistance heating of the oil-bearing fluid in the ground between the electrodes creates a pressure gradient, which drives hydrocarbon product into the electrodes. As long as the electrode is porous, then product can be collected from within the electrode. This method has not heretofore been used in any field relating to the extraction of oil from the ground.
[0004] The method of the invention is estimated to require an energy input equaling about 2% of the heating value of oil recovered. This calculation is based on an average of oil content of 14% by weight oil in the oil sand and 2% by weight of water and assuming all the electrical energy can be directed into the conductive water layer. This is a significant improvement over the state of the art, and unlike any other method, allows a wide margin for other heat losses in the process without impacting the energy balance for oil production from the deposit.
[0005] Energy savings from the invention are maximized taking advantage of the fact that the conductivity of oil sands is due to the interstitial liquid, the dielectric sand grains themselves having low conductivity. An electric current (flowing between electrodes or induced) heats up this interstitial liquid instantaneously, compared to steam flow and thermal conduction previously used in the industry.
[0006] Oil sands, also referred to as tar sands and bituminous sands, are a combination of clay, sand, water, and bitumen. Bitumen is the soluble organic matter and is an asphalt-like substance, which can be refined into oil. Oil sand deposits are typically mined using strip-mining techniques, which extract the oils sands from the ground for processing to recover the bitumen.
[0007] Tar sands deposits are found all over the world, with the largest deposits found in Venezuela and Alberta, Canada. These two deposits have been estimated to contain about 600 cubic kilometers of oil sands, equivalent to about twice the world's reserves of oil or about 3.5 trillion barrels of oil. The United States contains scattered deposits of oil sands, mainly in Utah, Kentucky, Kansas, Missouri, Oklahoma, California, and New Mexico. The ability to economically recover these deposits would help to diversify oil sources and contribute to U.S. national and energy security.
[0008] The invention may also be used for the extraction of oil in similar deposits, for example, in oil shale. Oil shale is a general term for shales rich enough in bituminous material to yield petroleum upon heating in low oxygen environments. The United States Office of Naval Petroleum and Oil Shale Reserves estimates a world supply of oil shale of about 1,700 billion barrels of which about 1,200 billion barrels is in the United States Estonia, Russia, Brazil, and China.
DESCRIPTION OF PRIOR ART
[0009] In a common oil extraction process, hot water is added to mined oil sand to liberate the bitumen from the sand and clay. The resulting slurry is piped to an extraction plant where the slurry is agitated to allow small air bubbles to attach to bitumen droplets. Froth is created, which is skimmed off the top and treated to remove residual water and fine solids. Bitumen is then upgraded in a coker, which cracks the bitumen into lighter oils and gases. Further processes create a blended synthetic crude oil.
[0010] An oil sands processing plant will typically consume over a million gallons of water every hour. The more efficient of such plants consume about 92 gallons of water per 42-gallon barrel of syncrude produced. Such a plant could produce about 75 million barrels of syncrude per year. Of the water used typically, about 250,000 gallons per hour is too contaminated with dissolved hydrocarbons and minerals for recycling. This quantity is sent to a tailings pond. While a tailings pond typically prevents contaminated water from mixing with potable water supplies, this much ponded water requires active management to permit settling of fines, to prevent it from combining with clean surface water and to preclude accidental release. The wet sand and clay residues can also be caustic and require extensive and expensive neutralization. This caustic aqueous residual often has a high Chemical Oxygen Demand, which robs the water of oxygen. This, in turn, makes the ponds containing such residual, hypoxic and adverse to plant and animal life.
[0011] Improvements in the basic hot water process have been disclosed, for example in U.S. Pat. No. 6,576,145 to Conaway on Jun. 10, 2003. The '145 patent is a continuous process where the mined oil sand is crushed to the particle size of sand or smaller, then mixed with water to form a slurry, then heated and blended with an oxidant in aqueous solution, such as hydrogen peroxide. This process releases the free interstitial hydrocarbons and those hydrocarbons bound electrostatically to the surfaces of clay-like particles in the ore. This process attempts to reduce water consumption through recycle and seeks to lower costs. However, while improved, this process has many of the same shortfalls of the basic hot water process.
[0012] It has been estimated that the equivalent of one barrel of oil is needed to process three barrels of synthetic crude obtained from oil sands using the hot water process. Aside from the cost, this much energy consumption translates to significant emissions of carbon dioxide, a greenhouse gas.
[0013] Five major disadvantages of producing oil from strip mined oil sands are (1) the need to consume large quantities of clean water resources, (2) the need to consume energy to heat the water, (3) the subsequent pollution of the water by chemicals extracted from the deposits, (4) a high cost of production; and (5) large up front capital investment is needed partly because very large separation plants are needed for processing the bitumen.
[0014] Since up to 80% of the oil sands deposits may be too deep underground for strip mining, other mining techniques have been employed. For example, in-situ mining techniques are practiced to extract the bitumen without removing oil sands from their in-ground location.
[0015] One such in-situ method requires a large source of steam, an injection borehole and an extraction borehole. This method is sometimes called “Steam-Assisted Gravity Drainage.” The steam is injected into the oil sands deposit where the combination of high temperature and steam creates a largely gaseous product that will flow and can be channeled to the extraction borehole. The product flow is liquefied before reaching the surface and pumped out of the extraction borehole. This in-situ technique suffers from the disadvantages noted in the preceding paragraph for the aboveground hot water process. In addition there is a potential for pollution below the surface.
[0016] The current invention improves on Steam-Assisted Gravity Drainage by employing controlled deposition of heat. In response to a current pulse between electrodes, resistive ionic conduction through paths of fluid interstitial to the dielectric grains in the body of oil sand produces an overpressure pulse. This drives the oil-bearing fluid towards the low-pressure outlets at the electrodes. Instantaneous heating with the IXOS device is dominant in the process. This compares to a slower rate of thermal conductive heating using the steam process. Therefore, the preferred embodiment of the present invention, which employs a high current pulse of short duration, offers significant benefits over steam extraction by minimizing wasted energy otherwise used for warming the ore (sand) in the deposit.
[0017] Another such in-situ method uses dissolution chemicals to dissolve the bitumen. The dissolved bitumen then flows to an extraction point, where it is removed for processing to extract the oil and recycle the dissolution chemicals.
[0018] All of the existing methods of extracting oil from oil sands have a large environmental cost. When strip mining is employed, two tons of mined sand are required to produce one barrel of synthetic crude. This leaves a significant tailings pile. The water ponds required to dispose of the water used in the process are contaminated and consume large tracts of land. Such underground processes also have potential to contaminate water aquifers.
[0019] The preferred embodiments of the device and method of the invention address many of the deficiencies found in the state of the art of oil extraction from oil sands. In particular, the present invention provides an in-situ process similar to an oil well, while eliminating extraction of oil sands and recovery of dissolution chemicals.
[0020] The preferred embodiment of the invention simplifies the process of oil extraction from oil sands by eliminating much of the surface infrastructure required to extract the oil sands and bitumen from the ground.
[0021] The preferred embodiment of the invention eliminates the need to consume large quantities of clean water resources. No water is used in the IXOS extraction process, except for the water already present in the deposit. Water is used only to provide minimal equipment cooling and to satisfy minor process needs.
[0022] The preferred embodiment of the invention avoids most of the cost, pollution and energy associated with the use of water and dissolution chemicals in the current methods. The preferred embodiment of the invention will help with minimization of cost, both in capital equipment and operation. The cost of electrical power is offset by low energy requirements. The costs for energy for extracting the bitumen are estimated to be about 2 percent of heating value of the oil recovered.
[0023] Pollution and energy are reduced as a necessary consequence of not using water and not needing to consume energy for heating water. Of major importance is the environmentally non-intrusive nature of in-situ production.
[0024] In terms of heating oil shale deposits for removing the oil, U.S. Pat. No. 6,929,067 to Vinegar, et al. on Aug. 16, 2005, which is incorporated by reference as if fully set forth herein, provides a thorough reference and description of heat sources with conductive material for in situ thermal processing of an oil shale formation. Essentially, the state of the art for electricity driven heating methods described involve electrically-powered, resistive heating elements placed in a well bore drilled into the formation. The heating elements are energized, much like that on an electric stovetop, and the heat generated by the elements is either carried to the formation by conduction or by radiation.
[0025] The preferred embodiment of the invention is different from all of the prior art described in the '067 patent in that this embodiment uses the in situ formation itself as the medium for carrying a current and, thus, heating itself from the flow of current.
[0026] It is therefore apparent that a need exists for a non-water consuming process for extracting oil from oil sands. It is further apparent that such a process that is also lower-cost, lower polluting, and lower energy process would significantly enhance the state of the art for producing oil from oil sands.
BRIEF SUMMARY OF THE INVENTION
[0027] A device and method of using the device provide for in-situ extraction of hydrocarbons from oil sands and other hydrocarbon resources. The preferred embodiment of the device includes at least two electrodes of tubular form wherein said electrodes are porous and capable of being inserted into the ground; a source of electrical current to apply to the electrodes; and a means for extracting the hydrocarbons from the tubular electrodes. In the preferred embodiment of the method of the invention, the electrodes are inserted into the oil deposit and connected to an electrical potential difference sufficient to drive an electric current between in-ground electrodes. Current is then flowed between the electrodes. The pressure gradient, resulting from heating the oil-bearing fluid, drives product into the tubular electrodes where it is removed.
BRIEF DESCRIPTION OF THE DRAWING
[0028] The drawing is a sectional view of the tubular porous electrodes for the in-situ extraction of oil from oil sands.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The device and method of using the device for the in-situ extraction of hydrocarbons from oil sand (herein referred to as “IXOS”) are based on the using the ionic resistivity of the hydrocarbon formation, also referred to as a deposit, by passing a current between electrodes in the formation.
[0030] The preferred embodiment of the IXOS device first includes a plurality of tubular porous electrodes similar to the one shown in the drawing. The tubular shape is typical of a well pipe or casing used in the oil industry. The porosity of the electrodes may be obtained by employing perforations, for example in the form of a pattern of short vertical slots (30) in the wall of the electrode tubes.
[0031] The electrodes are also similar to well-known technology of well points used for ground water extraction in that they are suitable for being inserted into the ground. While well points are porous casings used to extract water from an in ground well, the electrodes are used to extract hydrocarbons, such as soil containing a deposit of oil. Two significant differences from well point technology are the ability of the electrodes to carry electrical current for heating the ground deposit, and a consequent ability to motivate flow of the hydrocarbons from the ground resource into the hollow body of an electrode incident to extraction. In the preferred embodiment, the flow of electrical current between two or more electrodes is what motivates the flow.
[0032] The diameter and length of the electrodes can vary as required by the resource deposit. Typically, the electrodes would be steel tubes or casings (10) of about six-inches in diameter with a thickness of copper (20) on the inner wall to serve as a current carrier. However, electrode diameters of 10 feet, 20 feet or more are also within the scope of the invention. The length of the electrode is limited only by practicality constraints of handling and insertion into the deposit. Short lengths of electrodes may be joined in the same manner as well piping to make the electrode length any desired length suitable to the deposit and the source of power. Similar to a well point, an electrode may be fitted to the end of a pipe or casing. However, unlike a well point, the electrode must be insulated from the pipe or casing so that it is capable of delivering current to the specific resource location in the ground. At least two electrodes are needed in the preferred embodiment for the operation of the invention, and there is no limit on how many may be used.
[0033] The preferred embodiment of the IXOS device next includes a means for extracting the hydrocarbons from the tubular electrodes. In this embodiment, this means for extracting is a valve that is opened to allow the pressurized hydrocarbons and steam to flow out of the electrodes. In alternative embodiments, this means for extracting is a pump, which, for example, may either be placed within the electrode or on the surface.
[0034] The preferred embodiment of the IXOS device lastly includes a source of electrical current to apply to the electrodes. This typically means applying an electrical potential difference across two or more electrodes so that current will flow between them. Alternating or direct current may be employed.
[0035] In using the preferred embodiment of the IXOS device, the electrodes are inserted into the hydrocarbon containing deposit a distance from each other. Such distance is dependent upon the electrical resistivity of the ground and the electrical potential difference available to apply between electrodes. The determining factor is that the current passing through the deposit and between the electrodes must be sufficient to heat the deposit. Typically with tens of kilovolts available to apply to the electrodes, the electrodes would be spaced tens of meters apart.
[0036] In the preferred embodiment, the casings are vertical in orientation, but they may be in any orientation as long as they provide access to the surface so that the hydrocarbons can be removed from the tubular electrodes.
[0037] In the preferred embodiment of the method of the invention, a potential difference is applied between electrodes so that a current runs between them sufficient to heat the ground, that is, the deposit between the electrodes. For example, a 60 Hz potential difference in the range of several kilovolts causes an ionic current distribution in the conductive interstitial medium between the grains in the oil sand. Ionic resistance will generate local heating within the interstitial medium, causing the sequential melting of ice, the dislodging of oil particles, and pressure buildup through steam formation. Thus, the preferred embodiment of the invention avoids unnecessary heating of the bulk of the ore (sand) both by placing the heat exactly where it is needed (in the interstitial liquid), and by forestalling thermal conductivity losses. These embodiments take advantage of the benefit obtainable by employing a large current pulse of short duration to minimize conductive heat losses and to build high pressure for expelling product.
[0038] While the invention includes the application of a small current over a long time, embodiments of this type are less efficient in product delivery and more wasteful of energy. Such embodiments will work, but they promote less useful conductive heating of the bulk sands, and deliver a comparatively weak pressure rise from the vaporized liquids, which drive product into the electrode wells.
[0039] The preferred embodiment employs a current of about 1,000 amps delivered over a duration from about 20 seconds to 2 minutes. The current density can be reduced by increasing the diameter of the electrode. In one embodiment, pulsed current is generated on site using a motor and flywheel configured such that after the flywheel reaches a rotation corresponding to the energy desired, that rotational energy is discharged by turning a generator, which creates the desired pulse of electrical current.
[0040] A porous electrode allows ingress of steam-driven oil while keeping out sand grains. In this way each electrode essentially becomes a production well. The means for extracting the hydrocarbons is employed to produce oil and other hydrocarbons from the deposit.
[0041] The process works most efficiently when the current passing between electrodes is of such magnitude and duration that it does not directly heat the dielectric quartz sand grains. Thus, for the preferred embodiment, such current is pulsed and has a duration that minimizes thermal conduction into the solid centers of the sand grains. For this to occur, the resistive heating is applied rapidly enough to suppress to some extent the thermal conduction into the solid centers of the sand grains. This saves on energy consumed by the extraction process and contributes to an efficient process.
[0042] Important aspects of the process of using the invention are the modes of flexibility for adapting to different ground conditions present in a deposit.
[0043] A primary mode of flexibility relates to the electrodes, which can easily be rearranged and adapted to different conditions without the construction of new equipment. Hardness of the sand deposit and viscosity may vary radically with seasonal temperature changes, and the composition and physical nature of oil sands may differ substantially from one geographical location to another. In particular, this process is suitable for locations where the deposit, for example oil sand, is under large overburdens. In such cases, the embodiment would include electrically insulating sleeves over the electrodes where the electrodes are in contact with the overburden. Also, an alternative embodiment employed in such cases, comprises the electrode at the end of a casing penetrating the overburden wherein the electrode is electrically insulated from the casing. The presence of an overburden is expected to be of benefit when it acts as a seal for trapping vapor pressure.
[0044] Further modes of flexibility involve adjustable variables for optimizing the extraction of hydrocarbon from the deposit. These include voltage and frequency, geometry of electrode matrix, and time structure of electrical current.
[0045] In an alternative embodiment of the method of using the device, there is an additional step of injecting an electrolyte into the deposit. For example, in an oil sand deposit, salt water is injected through the electrode slots to raise conductivity of the deposit and to clear sand blockages of the electrode slots.
[0046] In an alternative embodiment of the method of using the IXOS device, there is an additional step of pressurizing one or more of the electrodes with nitrogen gas. This step helps to drive the oil product to unpressurized adjacent electrodes.
[0047] The description above and the examples noted are not intended to be the only embodiments of this invention and should not be construed as limiting the scope of the invention. These examples merely provide illustrations of some of the embodiments of this invention. Others will be obvious to those skilled in the art. Thus, the scope of the invention is determined by the appended claims and their legal equivalents rather than by the examples given. | A device and method of using the device enable the in-situ extraction of hydrocarbons from oil sands and other hydrocarbon resources. The preferred embodiment of the device includes at least two electrodes of tubular form wherein said electrodes are porous and capable of being inserted into the ground; a source of electrical current to apply to the electrodes; and a means for extracting the hydrocarbons from the tubular electrodes. In the preferred embodiment of the method of the invention, the electrodes are inserted into the oil deposit and connected to an electrical potential difference sufficient to drive an electric current between in-ground electrodes. Current is then flowed between the electrodes. The pressure gradient, resulting from heating the oil-bearing fluid, drives product into the tubular electrodes where it is removed. | 4 |
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure relates generally to a light fixture, and more particularly to a light fixture using solid state light emitters, e.g., light emitting diodes (LEDs) as a light source, wherein the light fixture is versatile regarding the illuminating area and intensity.
[0003] 2. Description of Related Art
[0004] LED lamp, a solid-state lighting, utilizes LEDs as a source of illumination, providing advantages such as resistance to shock and nearly limitless lifetime under specific conditions. Thus, LED lamps present a cost-effective yet high quality replacement for incandescent and fluorescent lamps.
[0005] A typical LED lamp is fixed onto a post and only illuminate at a given direction. In addition, the LED lamp provides a constant brightness at the given direction. This type of LED lamp fails to meet a requirement of an adjustable illumination direction or brightness.
[0006] What is need therefore is a light fixture which can overcome the above limitations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
[0008] FIG. 1 is an isometric, assembled view of a light fixture in accordance with a first embodiment of the present disclosure, with a part thereof being cut away for clarity.
[0009] FIG. 2 is a cross-sectional view of the light fixture in FIG. 1 , taken along line II-II thereof.
[0010] FIG. 3 is an isometric, assembled view of the light fixture in FIG. 1 , shown in a different status.
[0011] FIG. 4 is an isometric, assembled view of a light fixture in accordance with a second embodiment of the present disclosure.
DETAILED DESCRIPTION
[0012] A light fixture of the present disclosure can be applied in roadways, plazas, parks or other places needing illumination. As shown in FIG. 1 , the light fixture 10 in accordance with a first embodiment of the present disclosure comprises a post 11 , a first lamp 12 and a second lamp 13 both mounted on the post 11 . The post 11 has a columned fixing bar 111 at a top end thereof. The first and second lamps 12 , 13 are rotatably mounted on the fixing bar 111 .
[0013] The first lamp 12 comprises a first frame 121 , a plurality of first light sources 122 , and a plurality of first heat sinks 123 . The first light sources 122 are spaced from each other and received in the first frame 121 . The first heat sinks 123 each are thermally connected to a corresponding first light source 122 .
[0014] The first frame 121 has a substantially rectangular shape and is preferably made of metallic material. The first frame 121 comprises a first sleeve 1211 , and a plurality of first supporting parts 1212 and first hollow parts 1213 extending horizontally from the first sleeve 1211 in a first predetermined direction. The first sleeve 1211 is rotatably mounted on the fixing bar 111 and the first lamp 12 is capable of rotating in the horizontal plane with respect to a central axis O 1 O 2 of the fixing bar 111 . There are four first supporting parts 1212 and four first hollow parts 1213 in this embodiment. It is noted that, the numbers of the first supporting parts 1212 and the first hollow parts 1213 can be changed in other embodiments, such as only one first supporting part 1212 and one first hollow part 1213 in an alternative embodiment. The first supporting parts 1212 and the first hollow parts 1213 are alternately arranged along an elongated direction of the first frame 121 , i.e., a radial direction of the light fixture. That is, each one of the first hollow parts 1213 is located between two adjacent first supporting parts 1212 , excepting the one connecting to the first sleeve 1211 . It is to be understood that, in alternative embodiments, an additional first supporting part 1212 can be provided to connect with the first sleeve 1211 . In this way, every one of the first hollow parts 1213 is located between two adjacent first supporting parts 1212 . The first supporting parts 1212 and the first hollow parts 1213 each have a shape of an arc in a top plan view thereof, and the first supporting parts 1212 are concentric with the first hollow parts 1213 , each with a center thereof locating on the axis O 1 O 2 of the fixing bar 111 . The first hollow parts 1213 each define a window 1214 therein. The first supporting parts 1212 each form a sidewall which defines a first receiving room 1212 A for receiving a corresponding first light source 122 and a corresponding first heat sink 123 therein.
[0015] The first light sources 122 each comprise a first base 1221 and a plurality of first light emitting elements 1222 mounted on a bottom of the first base 1221 . In this embodiment, the first light emitting elements 1222 are LEDs. The first light emitting elements 1222 face downwardly to allow light generated therefrom to radiate downwards through the first receiving room 1212 A to lighten an object needing illumination. The first heat sink 123 is disposed on the first base 1221 of the first light source 122 to dissipate heat generated by the first light source 122 .
[0016] The second lamp 13 comprises a second frame 131 , a plurality of second light sources 132 spaced from each other and received in the second frame 131 , and a plurality of second heat sinks 133 each thermally connected to a corresponding second light source 132 .
[0017] The second frame 131 has a substantially rectangular shape and is preferably made of metallic material. The second frame 131 comprises a second sleeve 1311 , and a plurality of second supporting parts 1312 and second hollow parts 1313 extending horizontally from the second sleeve 1311 in a second predetermined direction which is different from the first predetermined direction. The second sleeve 1311 is rotatably mounted on the fixing bar 111 and located on the first sleeve 1211 of the first lamp 12 . The second lamp 13 is capable of rotating in the horizontal plane with respect to the center axis O 1 O 2 of the fixing bar 111 to change the angle between the first and second lamps 12 , 13 . The second supporting parts 1312 and the second hollow parts 1313 are alternately arranged. One of the second supporting parts 1312 connects to the second sleeve 1311 in this embodiment. It is to be understood that, in alternative embodiments, an additional second hollow part 1313 can be provided to connect with the second sleeve 1311 . Further, there are four second supporting parts 1312 and four second hollow parts 1313 in this embodiment. Of course the numbers of the second supporting parts 1312 and second hollow parts 1313 can be changed in other embodiments, such as only one of the second supporting parts 1312 and one of the second hollow parts 1313 in an alternative embodiment. The second supporting parts 1312 and the second hollow parts 1313 each have a shape of an arc in a top plan view thereof, and the second supporting parts 1312 are concentric with the second hollow parts 1313 , each with a center thereof locating on the axis O 1 O 2 of the fixing bar 111 . The second hollow parts 1313 each define a window 1314 therein. The second supporting parts 1312 each form a sidewall, which defines a second receiving room 1312 A for receiving a corresponding second light source 132 and a corresponding second heat sink 133 therein.
[0018] Referring to FIG. 2 , the second light sources 132 each comprise a second base 1321 and a plurality of second light emitting elements 1322 mounted on a bottom of the second base 1321 . In this embodiment, the second light emitting elements 1322 are LEDs. The second light emitting elements 1322 face to an opening of the second receiving room 1312 A to allow light generated therefrom projecting downwardly and out of the second receiving room 1312 A. The second heat sink 133 is disposed on the second base 1321 of the second light source 132 to dissipate heat generated by the second light source 132 .
[0019] The first and second lamps 12 , 13 are capable of rotating with respect to the fixing bar 111 , whereby the first and second lamps 12 , 13 can be oriented toward different directions or a same direction so that the light fixture 10 can be used to meet different requirements. As shown in FIG. 3 , the second lamp 13 is rotated to be oriented toward the first predetermined direction and fitly engaged with the first lamp 12 to increase a brightness in that direction. Specifically, the second supporting parts 1312 of the second lamp 13 are respectively located on the first hollow parts 1213 of the first lamp 12 , and the second hollow parts 1313 of the second lamp 13 are respectively located on the first supporting parts 1212 of the first lamp 12 . Since the first and second supporting (hollow) parts 1212 , 1312 ( 1213 , 1313 ) of the first and second lamps 12 , 13 are configured to be arc-shaped and have similar sizes, each second supporting part 1312 of the second lamp 13 can be fitly engaged between two corresponding adjacent first supporting parts 1212 of the first lamp 12 .
[0020] A circumferential length of the supporting (hollow) parts of the lamps can be changed as desired. FIG. 4 shows a light fixture 20 in accordance with a second embodiment of the present disclosure. Similar to the light fixture 10 of the first embodiment, the light fixture 20 also comprises a post 21 , a first lamp 22 and a second lamp 23 both rotatably mounted on the post 21 . The difference between the light fixtures 10 , 20 is that, first and second frames 221 , 231 of the first and second lamps 22 , 23 of the light fixture 20 each have a substantially semicircular shape. Specifically, the first frame 221 of the first lamp 22 comprises four semicircular first supporting parts 2212 and four semicircular first hollow parts 2213 . The first supporting parts 2212 and the first hollow parts 2213 are alternately arranged. The second frame 231 of the second lamp 23 comprises four semicircular second supporting parts 2312 and four semicircular second hollow parts 2313 . The second supporting parts 2312 and the second hollow parts 2313 are alternately arranged.
[0021] When the first and second lamps 22 , 23 are disengaged with each other, as shown in FIG. 4 , the first and second lamps 22 , 23 form a substantially round lamp with light sources received in the first and second supporting parts 2212 , 2312 . Since the first and second lamps 22 , 23 are capable of rotating with respect to the post 21 , the first lamp 22 can be fitly engaged with the second lamp 23 , with each second supporting part 2312 of the second lamp 23 fitly received between two corresponding adjacent first supporting parts 2212 of the first lamp 22 .
[0022] It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the disclosure. | An LED light fixture includes a post having a fixing bar at a top end thereof, a first lamp mounted on the fixing bar, and a second lamp rotatably mounted on the fixing bar. The first and second lamps are capable of rotating with respect to the fixing bar to change an angle between the first and second lamps, to thereby change an illumination area and intensity distribution of the LED light fixture. In one position, the second lamp overlaps the first lamp, and LED light sources in the first lamp are alternate with those of the second lamp. | 5 |
DESCRIPTION
FIELD OF THE INVENTION
The present invention concerns improved make-up brushes and more particularly eyelash brushes, that is to say brushes intended to apply a make-up product such as mascara to the eyelashes.
BACKGROUND OF THE INVENTION
The eyelash brushes known at present consist of a handle whose end carries the brush proper. They are generally made by means of tufts of bristles held between metal wire. Certain eyelash brushes have also been proposed in which these bristles are replaced by hook-shaped bristles of a material such as that sold under the Trade Name "VELCRO".
These brushes naturally have constant and well- defined characteristics, both as regards the disposition and distribution of the bristles in space and as regards the suppleness of hardness of the brush. Similarly, the quantity of the make-up product capable of being retained on the brush remains constant for a given make-up product. Now, the requirements of the users of these brushes may vary a very great deal. In fact, the shape, the number, the disposition and the length of the eyelashes may vary considerably from person to person, as may also their thickness and suppleness. Moreover, the make-up products currently on sale are becoming more and more numerous and have very different characteristics of colouring, viscosity etc. Finally, the make-up habits vary enormously from person to person.
The invention proposes to overcome these various problems and to supply an improved make-up brush, in particular an eyelash brush, which would be capable of being adapted to the various requirements encountered, whether these requirements are dictated by the user or related to the nature of the make-up product used. Moreover, the invention proposes to supply such a brush which could be of simple design, inexpensive, and easy to make.
SUMMARY OF THE INVENTION
The present invention provides an improved make-up brush, in particular an eyelash brush, comprising: shaft means; brush means including means regularly distributed around the longitudinal axis of the make-up brush to serve as bristles; and means actuable by the user for varying the diameter of the brush means, at least locally, at said regularly distributed bristle means.
Thus, the improved make-up brush according to the invention may adopt at least two stable states, that is to say, a small diameter state where the diametrical dimension of the brush means is minimal and a large diameter state wherein, on the contrary, this dimension is a maximum for at least a part of the length of the brush means at the bristle means.
However, in an improved mode of implementation, provision may be made for the brush to be maintained in intermediate states wherein the diametrical dimension of the brush means is intermediate between the maximum dimension and the minimum dimension.
In a first mode of implementation of the invention, the brush means carrying or having the regularly distributed bristle means, or at least a part of this brush means, is designed so as to be capable of varying its length under the effect of suitable actuation means and it is this variation of length which produces a variation in the brush diameter by deformation such that this diameter increases when the length decreases, and vice versa.
In a first embodiment of this mode of implementation, the brush means may comprise several deformable longitudinal strips distributed in the space around the longitudinal brush axis and interspaced by gaps, each strip carrying at least one row of bristles. The actuation means may then comprise a simple longitudinally movable rod, for example slideable, within the shaft, one of the ends of this rod forming or comprising an actuation element while the other end is connected to one end of the said strips whose other end is fixed in relation to the shaft. Thus by displacing the rod longitudinally in relation to the shaft, a shortening or an extension of the distance separating the ends of the strips carrying the bristles, and therefore a deformation resulting in variation in the diameter of the strips, is produced. The variations are most pronounced around the central portion of the strips which, because of this, assume a domed shape when they are in their maximum diameter state. The strips may advantageously be strips made of a synthetic or elastomeric material, the bristle extending preferably integrally from the strip and being made, for example, together with the latter by injection moulding.
By way of example a hollow sleeve, of a generally cylindrical shape, may thus be moulded of an elastomer and provided with bristles set up perpendicularly to the sleeve surface, preferably in the form of regular rows; after moulding, longitudinal gaps are cut into the sleeve to define the longitudinal strips of the sleeve, the gaps preferably not extending up to the ends of the sleeve.
It is thus possible to obtain at one and the same time a very important variation in diameter at the level of the central zone of the strips and, simultaneously, a variation in the suppleness of the brush.
In a second embodiment, the brush means comprises a bellows provided with successive notches and fins to form a kind of indentation so that the regularly distributed means serving as bristles are formed by the annular teeth of the identations constituted by the bellows.
Advantageously, the bellows has one of its own ends mounted at the end of the shaft and is fixed by its other end to the end of an actuator rod capable of being displaced between a sunken position in the shaft, wherein the bellows is elongated and has a reduced diameter, and a position which is partly extracted from the shaft, wherein the bellows is shortened and its diameter increased.
Preferably, the fixing of the bellows both at the end nearer the handle and at the other end to the rod is obtained by catch engagement.
This embodiment makes it possible, in particular, to cause the height of the teeth and the average space separating the teeth to vary, which correspondingly allows variation of both the quantity of the make-up product contained on the brush and the conditions of wiping the eyelashes.
In another mode of implementation, the regularly distributed bristle means may be mounted on sectors or longitudinal elements, for example strips carrying rows of bristles, these sectors being capable of being brought towards or moved away from the geometric brush axis, for instance, by means of a wedging device actuated by a suitable actuator rod.
In another mode of implementation, the regularly distributed bristle means may be carried by an elastomer sleeve which is capable of expanding its diameter, the sleeve being mounted on a diameter variation device, for example one of the wedging type.
BRIEF DESCRIPTION OF THE DRAWINGS
Other advantages and characteristics of the invention will emerge on reading the following description made by way of a non-restrictive example and referring to the attached drawing wherein:
FIG. 1 shows a longitudinal cross-sectional view of a first embodiment of an eyelash brush according to the invention, in its minimum diameter state.
FIG. 2 shows this brush in its maximum diameter state;
FIG. 3 shows the brush proper, in the state shown in FIG. 2;
FIG. 4, showing the brush proper in its minimum diameter state, is a longitudinal half section of a brush according to a second embodiment of the invention; and
FIG. 5 shows this brush in its maximum diameter state.
PREFERRED EMBODIMENTS OF THE INVENTION
Reference will first be made to FIGS. 1 to 3.
The eyelash brush according to the invention comprises an elongated tubular shaft 1 whose end is fixed in the usual way to a part 2 forming the closure of a container (not shown) for the eyelash make-up product. This closure part 2, which is of an enlarged diameter, has a skirt 3 provided with internal threads 4 for screwing closure part 2 on to the container neck. This closure part 2 also serves as a holding element for the user.
The tubular shaft 1 slideably encloses an elongate rod 5 whose top end is fixed to a button 6 having a suitably striated peripheral edge to facilitate gripping by the user. This button is movable between a high position as in FIG. 2, and a low position as in FIG. 1, and may be retained in these extreme positions thanks to slots 7 which are capable of cooperating with inner ribs 8 disposed within a recess 9 in the top of closure part 2. If button 6 is rotated around the longitudinal axis of rod 5, so as to align slots 7 with ribs 8, the ribs 8 may be dropped into the slots 7 and button 6 can thus come nearer to the rest of closure part 2, as shown in FIG. 1. If, on the other hand, the slots 7 are angularly offset relative to the ribs 8, the base of button 6 rests on the tops of ribs 8 and button 6 is thus found in its position remote from closure part 2, as shown in FIG. 2.
It will moreover be seen that the end 10 of rod 5 is rounded, for instance in the manner of a rivet head, and of diameter considerably greater than that of rod 5 and substantially the same as that of the end of tubular shaft 1 so that an elastomer sleeve may be disposed between these two ends to form the brush proper (generally designated 11). This sleeve, obtained for instance by injection moulding, has a hollowed out central part allowing the rod 5 to pass therethrough and has been moulded in the configuration shown in FIG. 1. It has, in fact, a generally cylindrical shape and comprises four radial gaps or slits whose length is shorter than the length of the sleeve so that these radial gaps or slits define four longitudinal strips 13 on the sleeve which are not interconnected except at the ends 14 of the sleeve. Each strip 13 has one or several rows of bristles or supple stumps 15 forming the bristles of the brush.
In the FIG. 1 configuration, the distance between the rounded end 10 of the rod 5 and the end of shaft 1 is practically equal to the length of sleeve 11 in its released state.
If, starting from this state, button 6 is pulled upwards to bring it into the FIG. 2 position, the distance between end 10 and the end of shaft 1 is shortened so that the various strips 13 of sleeve 11 become deformed outwardly by buckling, thus producing a pronounced increase in the brush diameter, this increase being at its maximum approximately midway along the sleeve. It will thus be understood that the brush may be used by a person either in the minimum diameter configuration shown in FIG. 1, or in the maximum diameter configuration shown in FIG. 2 wherein the button 6 has been rotated around its axis to ensure that the configuration is maintained. If the user wishes to return from the FIG. 2 position to that of FIG. 1, she only has to align the slots 7 with the ribs 8 and then the rod 5 moves downwards under the effect of the elastic force of the deformed sleeve 11 which tends to resume its elongated released position having the reduced diameter of FIG. 1.
By suitably determining the nature and thickness of the sleeve 11, different degrees of suppleness and user comfort may be obtained; this suppleness moreover varies according as to whether one is in the position of FIG. 1 or that of FIG. 2.
This embodiment may, of course, be subject to many variations. Thus, the number of strips may be higher than four, for instance, six or eight. The shape and disposition of the bristles can obviously be altogether different. The actuating mechanism may also vary according to all forms within the skill of the expert designing the brush. Finally, instead of being connected at their ends, the strips could be completely independent by being then connected, by suitable means, to the rod on the one hand and to the shaft on the other hand.
Reference will now be made to FIGS. 4 and 5.
In this embodiment, the shaft 1 and rod 5 slideable therewithin are retained. However, in this case the rod 5 is extended in a spherical end 16 which is preceded by a notch. The brush proper is constituted by a flexible bellows 17 forming successive annular teeth 18. The bottom rounded end 19 bounded by this bellows 17 has a small internal lip capable of coming into the notch between the end of rod 16 and the body of rod 5 for the purpose of fixing, by catch engagement, between the spherical end 16 and rod 5. At its open other end 20, the bellows also has a notch capable of allowing the fixing by catch engagement of the bellows end 20 against the lower end of hollow shaft 1, and is for this purpose provided with a small catch engagement bead capable of penetrating within this notch.
It will therefore be seen that since the bellows 17 is fixed, on the one hand, to the end of shaft 1 and, on the other hand, to the rod end 16 a rising motion of rod 5 produces a shortening of the bellows 17 and therefore an increase in the diameter of the tips of teeth 18 as well as of the depth of the notch separating two successive teeth 18. Moreover, a variation in suppleness of the bellows may be produced in this way.
Preferably, the bellows has sufficient elasticity to cause it to resume the elongated reduced diameter portion of FIG. 4 so that such a bellows 17 can be mounted on a device similar to that of FIGS. 1 and 2 with the same means of actuation.
Although the invention has been described with reference to special embodiments, it shall be duly understood that it is in no way limited thereto and that various modifications of shape and materials may be brought thereto without thereby departing either from the scope or spirit of the invention. | A make-up brush, in particular an eyelash brush, includes a bellows or longitudinally slit sleeve defining bristles and adapted to be varied in diameter, by variation in length, so as to suit the wishes of a user or the properties of a make-up product to be applied. | 0 |
BACKGROUND OF THE INVENTION
This invention relates generally to methods and arrangements for reducing partial discharges on printed circuit boards, and more particularly, to methods and arrangements for reducing partial discharges on printed circuit boards used in high voltage generators.
In high voltage generators used in medical imaging systems, such as, for example, an X-ray generator, high voltage DC is normally generated using a multiplier/doubler circuit operating at high frequency. The output voltage of the transformer is typically in tens of kilovolts (kV) and the operating frequency is in several tens of kilohertz (kHz). The rectifier units may include cascaded configurations to achieve a higher output voltage, as a higher output power is often needed for high quality X-ray generation. The operation of the rectifier units at these very high voltage levels and frequencies may result in high electrical and thermal stresses around the components on printed circuit boards (PCB).
Multiplier circuits are known to include components such as transformer coils, diodes, and capacitors mounted on a PCB forming a rectifier assembly and encased for example, within a polypropylene casing filled with oil. The oil around the multiplier PCB inside the polypropylene casing acts as a coolant and insulation.
Components and PCBs used in high and low voltage applications are likely to operate at very high stress levels. A configuration to reduce these stress zones requires adequate clearance and creepage distance between components mounted on the PCB. The amount of clearance depends on the breakdown strength of the surrounding medium such as air or oil. The creepage distance depends on the electric stress at the PCB surface and its interface with the ambient medium.
Further, and for example, in a multiplier PCB, the connections, for example, the transformer secondary coil connection to the diode through solder on the PCB (triple junction formed with solder, PCB and oil) and other diode solder points form high stress zones having electric stress. These high stress zones may cause partial discharges (PD) on the surface of the PCB that may be further enhanced at high temperature. Partial discharge and high temperature stresses together deteriorate transformer oil and PCB surface. Partial discharges may cause flashover between various components on the PCB if creepage distance is not adequate or cause puncture in the PCB if there is a significant accumulation of charges due to partial discharge on the surface of the PCB.
Thus, known methods of component mounting and connection may not provide compact assembly of components in a PCB in high power applications. Further, these may not provide reduced partial discharge conditions on the PCB.
BRIEF DESCRIPTION OF THE INVENTION
In one embodiment, a method for reducing partial discharge in a printed circuit board, is provided. The method includes providing a conducting surface coupled to a component under at least one of electrical and thermal stress in the printed circuit board, wherein the conducting surface is a metallic plate.
In yet another embodiment, a method for reducing partial discharge in a printed circuit board is provided. The method includes coupling a conductive element to a high voltage connection wherein the conductive element is a corona suppressor.
In another embodiment, a method for reducing partial discharge in a multiplier printed circuit board (PCB) is provided, the multiple PCB having components forming graded voltage levels at different locations in the PCB. The method includes providing multiple conducting surfaces coupled to at least one component under electrical and thermal stress on the PCB within an X-ray system wherein the conducting surfaces are metal plates.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side cross-sectional view of a PCB in an X-ray system according to an embodiment of the present invention.
FIG. 2 is a block diagram of a metallic plate and solid dielectric arrangement according to an embodiment of the present invention.
FIG. 3 is a side cross-sectional view of a PCB in an X-ray system with a corona suppressor according to an embodiment of the present invention.
FIG. 4 is a diagram of corona suppressor elements for use with a PCB according to various embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Various embodiments of the present invention provide a method of reducing partial discharges on printed circuit boards (PCBs) used especially in high voltage generators used in an X-ray system. However, the various embodiments are not so limited, and may be implemented in connection with other systems, such as, for example, diagnostic medical imaging systems, industrial inspection systems, security scanners, particle accelerators, etc.
FIG. 1 is a side cross-sectional view of a PCB in an X-ray system (not shown) according to one embodiment of the present invention. The PCB 400 includes a board member 40 having a first surface 401 on a first side and second surface 402 on a second side. In the embodiment shown, the first surface 401 is the component side of the PCB 400 and the second surface 402 is the solder side of the PCB 400 . The board member 40 may have other components, for example, a diode 42 if configured as a rectifier, and soldered on the PCB 400 . It should be noted that the rectifier PCB may include serial but zig-zag mounting of diodes (not shown) and thereby have graded voltage levels along its length.
A connection point 46 (e.g., solder joint) at the first surface 401 may be at a high voltage and susceptible to partial discharges due to high electric field concentration. The field concentration at the connection point 46 on the first surface 401 of the PCB 400 is substantially reduced by providing a conducting surface, for example, a metallic plate 45 having the same potential as the connection point 46 below the board member 40 . In the embodiment shown in FIG. 1 , the diode 42 also having similar voltage as the connection point 46 is electrically connected to the metallic plate 45 through leads 47 extending from the diode 42 through a dielectric 44 and connected (e.g., soldered) onto the metallic plate 45 . The metallic plate 45 is insulated from the solders at the second surface 402 . The dielectric 44 (e.g., epoxy) may be provided to the second surface 402 of the board member 40 to insulate the metallic plate 45 from the solder at the second surface 402 . The dielectric at the second surface of the board member also reduces or eliminates field concentration at various solder points on the solder side of the PCB 400 .
The electric field concentration at diode lead and PCB interface on the first surface may be reduced with use of plurality of metallic plates 51 as described in FIG. 2 . The metallic plates 51 may be connected with the last diode lead in a row and to a first diode 42 in the next row (not shown in the figure). These diode leads have similar potential and are at opposite sides of the PCB 400 due to serial, but zig-zag arrangement of the diodes 42 . The metallic plates 51 are thereby maintained at an electric potential substantially equal to the potential of diodes 42 on the first surface 401 . Note that the potential of the metal plates vary depending on the voltage gradient on the top surface of the PCB 400 . The dielectric 44 is used as insulation between the plates. The thickness of the insulation between the metallic plates and solder points to reduce partial discharges on the connection point and at diode leads is less and thereby results in a compact package for high power rectifier PCB.
The heat generated at the connection point 46 and at the diode 42 are distributed by conduction to the metallic plates 51 in the PCB 400 . It should be noted that in one embodiment the metallic plates 45 , 51 are configured having rounded edges to minimize the field concentration at the edges.
Further, in one embodiment, the dielectric 44 may be constructed or formed of an epoxy material and the metallic plates 51 may be constructed of copper. However, other materials may be used as the dielectric 44 and/or metallic plate 51 as desired or needed. For example, the dielectric may be insulating oil or any solidified or solid insulating material.
FIG. 3 is a side elevation view of a PCB 410 in an X-ray system according to another embodiment of the present invention. In this embodiment, the PCB 410 includes a board member 60 having a first surface 61 on a first side and a second surface 62 on a second side. The board member 60 includes a connection point, such as, for example, a solder joint 65 . A corona suppressor 68 is connected in the vicinity adjacent to or at the location of the solder joint 65 . The corona suppressor 68 includes a head 70 and may be configured as, for example, drawing board pins, paper clips, paper pins with round heads, screws, spirally wound single strand wires or other designs, and a combination thereof, as shown in FIG. 4 . By this connection, the corona suppressor 68 shields the solder joint 65 , thereby reducing the electric field intensity at the connection point (e.g., triple junction) on the PCB 410 . More specifically. the head 70 is positioned a distance from the first surface 61 and/or the second surface 62 of the board member 60 that includes the solder joint 65 such that the head 70 shields the solder joint 65 . The corona suppressor 68 may be coupled from either the first surface 61 or the second surface 62 or both the surfaces 61 and 62 .
It should be noted that various forms and configurations of corona suppressors may be constructed and provided as a component on the PCB 410 as desired or needed. Corona suppressors for PCB 410 may be standardized based on voltage rating and shield effectiveness.
Modifications to the embodiment shown in FIG. 3 are contemplated. For example, a corona suppressor 68 may be coupled to both the first surface 61 and second surface 62 of the board member 60 . Further, and for example, a plurality of corona suppressors 68 (shown in FIG. 4 ) may be connected at the solder joint 65 .
Thus, various embodiments of the present invention provide a PCB packaging that is constructed to have more uniform electrical stress distribution for reduced partial discharge during high power applications. Additionally, various embodiments include corona suppressors for PCBs to reduce partial discharges at connection points on the PCB.
While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims. | Methods and arrangements for reducing partial discharges on a printed circuit board are provided. A method of reducing partial discharge in a printed circuit board includes providing a conducting surface coupled to a component under at least one of electrical and thermal stress, wherein the conducting surface is a metallic plate. | 7 |
TECHNICAL FIELD
[0001] Embodiments of the present invention pertain to the field of semiconductor processing and, in particular, to methods for dicing substrates, each substrate having an integrated circuit (IC) thereon.
BACKGROUND DESCRIPTION OF RELATED ART
[0002] In semiconductor substrate processing, ICs are formed on a substrate (also referred to as a wafer), typically composed of silicon or other semiconductor material. In general, thin film layers of various materials which are either semiconducting, conducting or insulating are utilized to form the ICs. These materials are doped, deposited and etched using various well-known processes to simultaneously form a plurality of ICs, such as memory devices, logic devices, photovoltaic devices, etc, in parallel on a same substrate.
[0003] Following device formation, the substrate is mounted on a supporting member such as an adhesive film stretched across a film frame and the substrate is “diced” to separate each individual device or “die” from one another for packaging, etc. Currently, the two most popular dicing techniques are scribing and sawing. For scribing, a diamond tipped scribe is moved across a substrate surface along pre-formed scribe lines. Upon the application of pressure, such as with a roller, the substrate separates along the scribe lines. For sawing, a diamond tipped saw cuts the substrate along the streets. For thin substrate singulation, such as <150 μms (μm) thick bulk silicon singulation, the conventional approaches have yielded only poor process quality. Some of the challenges that may be faced when singulating die from thin substrates may include microcrack formation or delamination between different layers, chipping of inorganic dielectric layers, retention of strict kerf width control, or precise ablation depth control.
[0004] While plasma dicing has also been contemplated, a standard lithography operation for patterning resist may render implementation cost prohibitive. Another limitation possibly hampering implementation of plasma dicing is that plasma processing of commonly encountered interconnect metals (e.g., copper) in dicing along streets can create production issues or throughput limits. For example microcracks formed during the laser scribing process may remain following a plasma etch.
SUMMARY
[0005] Embodiments of the present invention include methods of laser scribing substrates. In the exemplary embodiment, the laser scribing is implemented with a laser beam having a centrally peaked spatial power profile to form a sloped ablated sidewall in a substrate.
[0006] In an embodiment, a method of dicing a semiconductor substrate having a plurality of ICs includes receiving a masked semiconductor substrate, the mask covering and protecting ICs on the substrate. The masked substrate is ablated along streets between the ICs with a laser beam having a centrally peaked spatial power profile. In one embodiment, a center portion of the mask thickness and a thin film device thickness in the street is ablated through to provide a patterned mask with a positively sloped profile. A portion of the substrate ablated by the laser also has a positively sloped profile along a plane substantially perpendicular to the direction of laser travel. Sloped sidewall of the substrate are etched with an anisotropic deep trench etch process to singulate the dice and remove microcracks in the substrate generated during laser scribe.
[0007] In another embodiment, a system for dicing a semiconductor substrate includes a laser scribe module and a plasma etch chamber, integrated onto a same platform. The laser scribe module is to ablate material with a laser beam having a centrally peaked spatial power profile and the plasma chamber is to etch through the substrate and singulate the IC chips in a manner which removes microcracks in the substrate generated by the laser ablation. The laser scribe module may include a beam shaper to provide the centrally peaked spatial power profile.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Embodiments of the present invention are illustrated by way of example, and not limitation, in the figures of the accompanying drawings in which:
[0009] FIG. 1A is a graph illustrating a top hat laser beam spatial profile;
[0010] FIG. 1B is a cross-sectional view of a trench ablated in a substrate with a laser beam having the spatial profile illustrated in FIG. 1A ;
[0011] FIG. 2A is a graph illustrating a laser beam with a centrally peaked spatial profile, in accordance with an embodiment of the present invention;
[0012] FIG. 2B is a cross-sectional view of a trench ablated in a substrate with a laser beam having the spatial profile illustrated in FIG. 2A , in accordance with an embodiment of the present invention;
[0013] FIG. 2C is a cross-sectional view of an anisotropically etched trench in a substrate which had been ablated by a laser beam having the spatial profile illustrated in FIG. 2A ;
[0014] FIG. 3A is a flow diagram of a hybrid laser scribing plasma etch dicing process, in accordance with an embodiment of the present invention;
[0015] FIG. 3B is a flow diagram of a mask application method which may be practiced as part of the hybrid laser scribing plasma etch dicing process illustrated in FIG. 3A , in accordance with an embodiment of the present invention;
[0016] FIG. 4A illustrates a cross-sectional view of a substrate including a plurality of ICs corresponding to operation 301 of the dicing method illustrated in FIG. 3 , in accordance with an embodiment of the present invention;
[0017] FIG. 4B illustrates a cross-sectional view of a substrate including a plurality of ICs corresponding to operation 325 of the dicing method illustrated in FIG. 1 , in accordance with an embodiment of the present invention;
[0018] FIG. 4C illustrates a cross-sectional view of a substrate including a plurality of ICs corresponding to operation 330 of the dicing method illustrated in FIG. 1 , in accordance with an embodiment of the present invention;
[0019] FIG. 4D illustrates a cross-sectional view of a semiconductor substrate including a plurality of ICs corresponding to operation 340 of the dicing method illustrated in FIG. 1 , in accordance with an embodiment of the present invention;
[0020] FIG. 5 illustrates an expanded cross-sectional view of an mask and thin film device layer stack ablated by a laser and plasma etched, in accordance with embodiments of the present invention;
[0021] FIG. 6A illustrates a block diagram of an integrated platform layout for laser and plasma dicing of substrates, in accordance with an embodiment of the present invention; and
[0022] FIG. 6B illustrates a block diagram of a laser scribing module for laser scribing, in accordance with an embodiment of the present invention; and
[0023] FIG. 7 illustrates a block diagram of an exemplary computer system which controls automated performance of one or more operation in the laser scribing methods described herein, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0024] Methods of dicing substrates, each substrate having a plurality of ICs thereon, are described. In the following description, numerous specific details are set forth, such as femtosecond laser scribing and deep silicon plasma etching conditions in order to describe exemplary embodiments of the present invention. However, it will be apparent to one skilled in the art that embodiments of the present invention may be practiced without these specific details. In other instances, well-known aspects, such as IC fabrication, substrate thinning, taping, etc., are not described in detail to avoid unnecessarily obscuring embodiments of the present invention. Reference throughout this specification to “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrase “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments. Also, it is to be understood that the various exemplary embodiments shown in the Figures are merely illustrative representations and are not necessarily drawn to scale.
[0025] The terms “coupled” and “connected,” along with their derivatives, may be used herein to describe structural relationships between components. It should be understood that these terms are not intended as synonyms for each other. Rather, in particular embodiments, “connected” may be used to indicate that two or more elements are in direct physical or electrical contact with each other. “Coupled” my be used to indicate that two or more elements are in either direct or indirect (with other intervening elements between them) physical or electrical contact with each other, and/or that the two or more elements co-operate or interact with each other (e.g., as in a cause an effect relationship).
[0026] The terms “over,” “under,” “between,” and “on” as used herein refer to a relative position of one material layer with respect to other material layers. As such, for example, one layer disposed over or under another layer may be directly in contact with the other layer or may have one or more intervening layers. Moreover, one layer disposed between two layers may be directly in contact with the two layers or may have one or more intervening layers. In contrast, a first layer “on” a second layer is in contact with that second layer. Additionally, the relative position of one layer with respect to other layers is provided assuming operations are performed relative to a substrate without consideration of the absolute orientation of the substrate.
[0027] Generally, described herein is a laser scribe process employing a laser having a beam with a centrally peaked and sloped spatial power profile to ablate a predetermined path through an unpatterned (i.e., blanket) mask layer, a passivation layer, and subsurface thin film device layers. The laser scribe process may then be terminated upon exposure of, or partial ablation of, the substrate. Any ablation of the substrate by the peaked beam profile will tend to advantageously form positively sloped substrate sidewalls. In accordance with an embodiment of the present invention, the peaked spatial profile is provided in a femtosecond laser. Femtosecond laser scribing is an essentially, if not completely, non-equilibrium process. For example, the femtosecond-based laser scribing may be localized with a negligible thermal damage zone. In an embodiment, femtosecond laser scribing is used to singulate ICs having ultra-low κ films (i.e., with a dielectric constant below 3.0). In one embodiment, direct writing with a laser eliminates a lithography patterning operation, allowing the masking material to be something other than a photo resist as is used in photolithography. In the exemplary hybrid dicing embodiment, the laser scribing process is followed by a plasma etch through the bulk of the substrate which removes most or all of microcracks in the substrate generated by the laser ablation. In one such embodiment, a substantially anisotropic etching is used to complete the dicing process in a plasma etch chamber; the anisotropic etch achieving a high directionality into the substrate by depositing on sidewalls of the etched trench an etch polymer.
[0028] FIG. 1A is a graph illustrating a top hat laser beam spatial profile 100 which provides a substantially flat power level (P) across a beam width W 1 along at least the direction x, which is in a direction substantially perpendicular to a direction of laser beam travel relative to the substrate. The top hat beam spatial profile 100 is typically the same in the direction y (direction of laser beam travel relative to a substrate) for a symmetrical spatial profile. To generate the top hat beam spatial profile 100 , conventional diffractive optical elements and shaping techniques may be applied to truncate power in the tails in regions below x 0 and above x 1 for a TM mode laser source having a substantially Gaussian profile so that there is effectively a uniform energy density.
[0029] FIG. 1B is a cross-sectional view of a trench ablated in a substrate 106 with a laser beam having the spatial profile illustrated in FIG. 1A . As shown, the ablated trench 112 has a nominal kerf width KW 1 at a substrate top surface 117 which is a function of the beam width W 1 . The uniform energy density of the laser beam profile 100 renders the kerf width KW 1 substantially constant with/independent of trench depth such that the trench bottom 119 also has an effective nominal kerf width of KW 1 . It has been found that ablating the trench 112 also generates a number of microcracks in the substrate 106 (e.g., single crystalline silicon substrate) below the trench bottom 119 and emanating from the trench sidewalls. Though not bound by theory, it is currently thought such microcrack formation results from substrate heating during the ablation process. As shown in FIG. 1B , microcracks may be further classified as vertically propagating cracks 108 or laterally propagating cracks 109 . Vertically propagating cracks 108 tend to emanate from the trench bottom 119 in a direction substantially parallel with the trench sidewalls 118 while horizontally propagating cracks 109 emanate from the sidewalls 118 or trench bottom 119 in a direction non-parallel with the trench sidewalls 118 . For the hybrid scribing methods described herein, where a plasma etch subsequent to the laser ablation of trench 112 will advance the trench bottom 119 through the substrate with anisotropic etch, the vertically propagating cracks 108 will be eliminated. Horizontally propagating cracks 109 however pose a risk of surviving an anisotropic etch process which does not significantly etch the trench sidewall 118 . Because the trench 112 may be just below a device thin film layer 104 , horizontally propagating cracks 109 which survive the singulation process pose a risk of continuing to run out laterally (non-parallel to the sidewall 118 ) and adversely affect product die adjacent to the trench 112 .
[0030] While it has been found by the inventor and his associates that a femtosecond laser advantageously reduces the occurrence of all microcracks in the substrate, the inventor has further found that of the fewer remaining microcracks the ratio of vertically oriented microcracks to horizontally oriented microcracks can be increased significantly when a centrally peaked spatial power profile is employed FIG. 2A is a graph illustrating the femtosecond laser beam has a centrally peaked spatial profile rather than the top-hat profile 100 . It should be noted that this phenomena has been found in testing performed with a femtosecond laser, and therefore although it is currently thought that the effect may be generalized to lasers of greater pulse widths (e.g., picosecond lasers), this remains unconfirmed.
[0031] FIG. 2A is a graph illustrating a laser beam with a centrally peaked spatial profile 200 , in accordance with an embodiment of the present invention. The centrally peaked spatial profile 200 provides a varying power level (P) across a beam width W 2 (as measured in a manner consistent with that for W 1 ) along at least the direction x, which is in a direction substantially perpendicular to a direction of laser beam travel relative to the substrate. The centrally peaked spatial profile 200 may further be the same in the direction y (direction of laser beam travel relative to a substrate) for a symmetrical spatial profile. Generally, the laser beam profile may be any which has a non-uniform energy density with a peak power approximately centered within the beam width W 2 (i.e., approximately centered between x 0 and x 1 ). In one embodiment, the centrally peaked spatial profile 200 is a Gaussian profile, for example of a TM mode source. In a further embodiment, the centrally peaked spatial profile 200 is nearly a Gaussian profile with the profile function deviating by no more than 10% from the Gaussian function at any point along the x-axis across the beam width W 2 (e.g., between x 0 and x 1 ). In alternative embodiments, conventional diffractive optical elements and shaping techniques may be applied to modulate the slope of laser power from a TM mode laser source as a function of x between x 0 and above x 1 to increase or decrease a delta between a peak power P((x 1 −x 0 )/2) relative to power at the beam edge P(x 0 ); P(x 1 ) relative to a Gaussian profile.
[0032] FIG. 2B is a cross-sectional view of a trench ablated in a substrate with a laser beam having the non-uniform spatial profile illustrated in FIG. 2A , in accordance with an embodiment of the present invention. As shown, the ablated trench has a substrate sidewall 213 with a positive slope. More specifically, at a region adjacent to an interface between a substrate 206 and an overlying thin film device layer 204 , the laser ablated trench 212 has a first kerf width KW 1 while at a region below the interface, the ablated trench 212 has a second kerf width KW 2 which is smaller than the first kerf width KW 1 . The second kerf width KW 2 may be measured anywhere below a top surface of the substrate 206 or interface with the thin film device layer 204 (i.e., just below the surface or at the bottom of the ablated trench). In one such embodiment, the second kerf width KW 2 is less than 75% of the first kerf width KW 1 . In another embodiment, the second kerf width KW 2 is less than 50% of the first kerf width KW 1 .
[0033] In embodiments, the laser beam spatial profile is such that the power (P) at the peak of the spatial power profile is sufficient to expose the substrate and the power at the full width quarter maximum (FWQM) is insufficient to expose the substrate. As further shown in FIG. 2A , the FWQM line is below a threshold power T 1 required to ablated through the mask 202 thickness and thin film device stack 204 thickness to expose the substrate 206 . As such, the first kerf width KW 1 is a function of the beam width W 2 exceeding that threshold power T 1 with regions outside of W 2 ablating less than the entire thickness of the mask 202 and thin film device stack 204 . In the exemplary embodiment having a Gaussian profile which extends beyond W 2 , the sidewalls of both the thin film device stack 204 and mask 202 are also positively sloped such that the ablated trench 212 has a third kerf width KW 3 in a region adjacent to the mask 202 that is larger than the first kerf width KW 1 . For alternative embodiments, the positive slope of the mask 202 and/or thin film device stack 204 is reduced or made substantially vertical by truncating the tails of the centrally peaked profile 200 beyond x 0 and x 1 using known techniques.
[0034] For certain beam embodiments employing the centrally peaked spatial profile 200 , and more particularly those of a femtosecond laser, a greater percentage of microcracks generated in the substrate 208 may be vertically propagating microcracks 208 and as further illustrated in FIGS. 2B and 2C , the positive slope of the sidewall 213 also leaves more of the substrate material lining the ablated trench 212 (which may have microcracks) exposed to the subsequent plasma etch so that microcracks (vertically propagating or otherwise) may be removed as part of the singulation process.
[0035] FIG. 2C is a cross-sectional view of an anisotropically etched trench 413 in the substrate 206 which had been ablated by a laser beam having the spatial profile illustrated in FIG. 2A . For example, as illustrated in FIG. 2C by dashed lines, mirocracks (e.g., vertically oriented microcracks 208 ) are consumed as the etch front passes through the thickness of the substrate 206 . In the exemplary embodiment where the etched trench has a further kerf width KW 4 , the sloped ablated trench sidewalls 213 are consumed as the etch front generates substantially vertical sidewalls 217 extending through the substrate 206 . For the exemplary embodiment where the thin film device stack 204 masks the plasma etch process responsible for the etched trench 213 , the etched trench 213 has a fourth kerf width KW 4 which is approximately equal (i.e., +/−10%) to the first kerf width KW 1 and therefore greater than the second kerf width KW 2 .
[0036] FIG. 3A is a flow diagram illustrating a hybrid laser ablation-plasma etch singulation method 300 employing iterative laser scribing, in accordance with an embodiment of the present invention. FIGS. 4A-4D illustrate cross-sectional views of a substrate 406 including first and second ICs 425 , 426 corresponding to the operations in method 300 , in accordance with an embodiment of the present invention.
[0037] Referring to operation 301 of FIG. 1 , and corresponding FIG. 4A , a substrate 406 is received. The substrate 406 includes a mask 402 covering a thin film device layer stack 401 comprising a plurality of distinct materials found both in the ICs 425 , 426 and intervening street 427 between the ICs 425 , 426 . Generally, the substrate 406 is composed of any material suitable to withstand a fabrication process of the thin film device layers formed thereon. For example, in one embodiment, substrate 406 is a group IV-based material such as, but not limited to, monocrystalline silicon, germanium or silicon/germanium. In another embodiment, substrate 406 is a III-V material such as, e.g., a III-V material substrate used in the fabrication of light emitting diodes (LEDs). During device fabrication, the substrate 406 is typically 600 μm-800 μm thick, but as illustrated in FIG. 4A may have been thinned to less than 100 μm and sometimes less than 50 μm with the thinned substrate now supported by a carrier 411 , such as a backing tape 410 stretched across a support structure of a dicing frame (not illustrated) and adhered to a backside of the substrate with a die attach film (DAF) 408 .
[0038] In embodiments, first and second ICs 425 , 426 include memory devices or complimentary metal-oxide-semiconductor (CMOS) transistors fabricated in a silicon substrate 406 and encased in a dielectric stack. A plurality of metal interconnects may be formed above the devices or transistors, and in surrounding dielectric layers, and may be used to electrically couple the devices or transistors to form the ICs 425 , 426 . Materials making up the street 427 may be similar to or the same as those materials used to form the ICs 425 , 426 . For example, street 427 may include thin film layers of dielectric materials, semiconductor materials, and metallization. In one embodiment, the street 427 includes a test device similar to the ICs 425 , 426 . The width of the street 427 may be anywhere between 10 μm and 200 μm, measured at the thin film device layer stack/substrate interface.
[0039] In embodiments, the mask 402 may be one or more material layers including any of a plasma deposited polymer (e.g., C x F y ), a water soluble material (e.g., poly(vinyl alcohol)), a photoresist, or similar polymeric material which may be removed without damage to an underlying passivation layer, which is often polyimide (PI) and/or bumps, which are often copper. The mask 402 is to be of sufficient thickness to survive a plasma etch process (though it may be very nearly consumed) and thereby protect the copper bumps which may be damaged, oxidized, or otherwise contaminated if exposed to the substrate etching plasma.
[0040] FIG. 5 illustrates an expanded cross-sectional view 500 of a bi-layer mask including a mask layer 402 B (e.g., C x F y polymer) applied over a mask layer 402 A (e.g., a water soluble material) in contact with a top surface of the IC 426 and the street 427 , in accordance with embodiments of the present invention. As shown in FIG. 5 , the substrate 406 has a top surface 503 upon which thin film device layers are disposed which is opposite a bottom surface 502 which interfaces with the DAF 408 ( FIG. 4A ). Generally, the thin film device layer materials may include, but are not limited to, organic materials (e.g., polymers), metals, or inorganic dielectrics such as silicon dioxide and silicon nitride. The exemplary thin film device layers illustrated in FIG. 5 include a silicon dioxide layer 504 , a silicon nitride layer 505 , copper interconnect layers 508 with low-κ (e.g., less than 3.5) or ultra low-κ (e.g., less than 3.0) interlayer dielectric layers (ILD) such as carbon doped oxide (CDO) disposed there between. A top surface of the IC 426 includes a bump 512 , typically copper, surrounded by a passivation layer 511 , typically a polyimide (PI) or similar polymer. The bump 512 and passivation layer 511 therefore make up a top surface of the IC with the thin film device layers forming subsurface IC layers. The bump 512 extends from a top surface of the passivation layer 511 by a bump height H B which in the exemplary embodiments ranges between 10 μm and 50 μm. One or more layers of the mask may not completely cover a top surface of the bump 512 , as long as at least one mask layer is covering the bump 512 for protection during substrate plasma etch.
[0041] Referring back to FIG. 3A , in certain embodiments the mask 402 may be applied as part of the method 300 , for example where an integrated processing platform includes a module for applying the mask 402 . FIG. 3B is a flow diagram of one exemplary mask application method 350 which may be practiced as part of the hybrid laser scribing plasma etch dicing process illustrated in FIG. 3A , in accordance with an embodiment of the present invention. At operation 302 , a substrate is loaded onto a spin coat system or transferred into a spin coat module of an integrated platform. At operation 304 an aqueous solution of a water soluble polymer is spun over the passivation layer 511 and bump 512 ( FIG. 5 ). Experiments conducted with PVA solutions showed a non-planarized coverage of 50 μm bumps a T min greater than 5 μm and a T max at the street less than 20 μm.
[0042] At operation 308 the aqueous solution is dried, for example on a hot plate, and the substrate unloaded for laser scribe or transferred in-vaccuo to a laser scribe module at operation 320 for completion of the method 300 ( FIG. 3A ). For particular embodiments where the water soluble layer is hygroscopic, in-vaccuo transfer is particularly advantageous. The spin and dispense parameters are a matter of choice depending on the material, substrate topography and desired layer thickness. The drying temperature and time should be selected to provide adequate etch resistance while avoiding excessive crosslinking which renders removal difficult. Exemplary drying temperatures range from 60° C. to 150° C. depending on the material. For example, PVA was found to remain soluble at 60° C. while becoming more insoluble as the temperature approached the 150° C. limit of the range.
[0043] Returning to FIG. 3A , at operation 325 a predetermined pattern is directly written into the mask 402 with ablation along a controlled path relative to the substrate 406 . As illustrated in corresponding FIG. 4B , the mask 402 is patterned by laser radiation 411 having a centrally peak spatial profile to form the trench 414 extending through the mask thickness and through the thin film device layer stack 404 to expose the substrate 406 . The ablated trench 414 has the positively sloped sidewalls such that a portion of the trench adjacent to the top surface of the substrate 406 has a first kerf width KW 1 and the bottom of the trench extending below the top surface of the substrate 406 has a second kerf width KW 2 , as previously described herein.
[0044] In an embodiment the laser radiation 412 entails beam with a pulse width (duration) in the femtosecond range (i.e., 10 −15 seconds). Laser parameter selection, such as pulse width, may be critical to developing a successful laser scribing and dicing process that minimizes chipping, microcracks and delamination in order to achieve clean laser scribe cuts. As previously noted, laser pulse width in the femtosecond range advantageously mitigates heat damage issues relative longer pulse widths (e.g., picosecond or nanosecond). Although not bound by theory, as currently understood a femtosecond energy source avoids low energy recoupling mechanisms present for picosecond sources and provides for greater thermal nonequilibrium than does a nanosecond or even picosecond source. With nanosecond or picoseconds laser sources, the various thin film device layer materials present in the street 427 behave quite differently in terms of optical absorption and ablation mechanisms. For example, dielectrics layers such as silicon dioxide, is essentially transparent to all commercially available laser wavelengths under normal conditions. By contrast, metals, organics (e.g., low-κ materials) and silicon can couple photons very easily, particularly nanosecond-based or picosecond-based laser irradiation. If non-optimal laser parameters are selected, in a stacked structures that involve two or more of an inorganic dielectric, an organic dielectric, a semiconductor, or a metal, laser irradiation of the street 427 may disadvantageously cause delamination. For example, a laser penetrating through high bandgap energy dielectrics (such as silicon dioxide with an approximately of 9 eV bandgap) without measurable absorption may be absorbed in an underlying metal or silicon layer, causing significant vaporization of the metal or silicon layers. The vaporization may generate high pressures potentially causing severe interlayer delamination and microcracking. Femtosecond-based laser irradiation processes have been demonstrated to avoid or mitigate such microcracking or delamination of such material stacks.
[0045] In an embodiment, the laser source for operation 325 has a pulse repetition rate approximately in the range of 200 kHz to 10 MHz, although preferably approximately in the range of 500 kHz to 5 MHz. The laser emission generated at operation 201 may span any combination of the visible spectrum, the ultra-violet (UV), and/or infra-red (IR) spectrums for a broad or narrow band optical emission spectrum. Even for femtosecond laser ablation, certain wavelengths may provide better performance than others depending on the materials to be ablated. In a specific embodiment, a femtosecond laser suitable for semiconductor substrate or substrate scribing is based on a laser having a wavelength of approximately between 1570-200 nanometers, although preferably in the range of 540 nanometers to 250 nanometers. In a particular embodiment, pulse widths are less than or equal to 500 femtoseconds for a laser having a wavelength less than or equal to 540 nanometers. In an alternative embodiments, dual laser wavelengths (e.g., a combination of an IR laser and a UV laser) are used to generate the beam at operation 201 . In an embodiment, the laser source delivers pulse energy at the work surface approximately in the range of 0.5 μJ to 100 μJ, although preferably approximately in the range of 1 μJ to 5 μJ.
[0046] At operation 325 , the spatially peaked beam is controlled to travel a predetermined path relative to the substrate to ablate a point on the mask 402 . In an embodiment, the laser scribing process runs along a work piece surface in the direction of travel at a speed approximately in the range of 500 mm/sec to 5 msec, although preferably approximately in the range of 600 mm/sec to 2 msec. At operation 220 , method 200 returns to FIG. 1 for plasma etch of the exposed substrate.
[0047] Returning to FIGS. 3A and 4D , the substrate 406 is exposed to a plasma 416 to etch through the ablated trench 414 to singulate the ICs 426 at operation 330 . In the exemplary embodiment. In accordance with an embodiment of the present invention, etching the substrate 406 at operation 330 includes anisotropically advancing the trench 414 formed with the laser scribing process entirely through substrate 406 , as depicted in FIG. 4D . A high-density plasma source operating at high powers may be used for the plasma etching operation 330 . Exemplary powers range between 3 kW and 6 kW, or more. High powers provide advantageously high etch rates. For example, in a specific embodiment, the etch rate of the material of substrate 406 is greater than 25 μms per minute.
[0048] In one embodiment, a deep silicon etch (e.g., such as a through silicon via etch) is used to etch a single crystalline silicon substrate or substrate 406 at an etch rate greater than approximately 40% of conventional silicon etch rates while maintaining essentially precise profile control and virtually scallop-free sidewalls. Effects of the high power on any water soluble material layer present in the mask 402 are controlled through application of cooling power via an electrostatic chuck (ESC) chilled to −10° C. to −15° C. to maintain the water soluble mask material layer at a temperature below 100° C. and preferably between 70° C. and 80° C. throughout the duration of the plasma etch process. At such temperatures, water solubility is advantageously maintained.
[0049] In a specific embodiment, the plasma etch operation 330 further entails a plurality of protective polymer deposition cycles interleaved over time with a plurality of etch cycles. The duty cycle may vary with the exemplary duty cycle being approximately 1:1-1:2 (etch:dep). For example, the etch process may have a deposition cycle with a duration of 250 msec-750 msec and an etch cycle of 250 msec-750 msec. Between the deposition and etch cycles, an etching process chemistry, employing for example SF 6 for the exemplary silicon etch embodiment, is alternated with a deposition process chemistry employing a polymerizing fluorocarbon (C x F y ) gas such as, but not limited to, C 4 F 6 or C 4 F 8 or fluorinated hydrocarbon (CH x F y with x>=1), or XeF 2 . Process pressures may further be alternated between etch and deposition cycles to favor each in the particular cycle, as known in the art.
[0050] At operation 340 , method 300 is completed with removal of the mask 402 . In an embodiment, a water soluble mask layer is washed off with water, for example with a pressurized jet of de-ionized water or through submergence in an ambient or heated water bath. In alternative embodiments, the mask 402 may be washed off with aqueous solvent solutions known in the art to be effective for etch polymer removal. Either of the plasma singulation operation 330 or mask removal process at operation 340 may further pattern the die attach film 408 , exposing the top portion of the backing tape 410 .
[0051] A single integrated process tool 600 may be configured to perform many or all of the operations in the hybrid laser ablation-plasma etch singulation process 300 . For example, FIG. 6A illustrates a block diagram of a cluster tool 606 coupled with laser scribe apparatus 610 for laser and plasma dicing of substrates, in accordance with an embodiment of the present invention. Referring to FIG. 6A , the cluster tool 606 is coupled to a factory interface 602 (FI) having a plurality of load locks 604 . The factory interface 602 may be a suitable atmospheric port to interface between an outside manufacturing facility with laser scribe apparatus 610 and cluster tool 606 . The factory interface 602 may include robots with arms or blades for transferring substrates (or carriers thereof) from storage units (such as front opening unified pods) into either cluster tool 606 or laser scribe apparatus 610 , or both.
[0052] A laser scribe apparatus 610 is also coupled to the FI 602 . FIG. 6B illustrates an exemplary functional block diagram of the laser scribe apparatus 610 . In an embodiment illustrated in FIG. 6B , the laser scribe apparatus 610 includes a laser 665 , which may be a femtosecond laser as described elsewhere herein. The laser 665 is to performing the laser ablation portion of the hybrid laser and etch singulation process 300 . In one embodiment, a moveable stage 406 is also included in laser scribe apparatus 610 , the moveable stage 406 configured for moving a substrate or substrate (or a carrier thereof) relative to the femtosecond-based laser. As further illustrated, the laser scribe apparatus includes a scanner 670 (i.e., galvanometer) with a mirror movable to scan the laser beam in response to control signals from the controller 680 . Depending on the implementation, the laser 665 either provides a centrally peak beam profile (e.g., Gaussian) as described elsewhere herein or between the femtosecond laser 665 and scanner 670 are beam shaping optics 660 which are to provide the centrally peaked beam profile substantially as shown in FIG. 2A .
[0053] Returning to FIG. 6A , the cluster tool 606 includes one or more plasma etch chambers 608 coupled to the FI by a robotic transfer chamber 650 housing a robotic arm for in-vaccuo transfer of substrates between the laser scribe module 610 , etch chamber(s) 608 and/or mask module 614 . The plasma etch chambers 608 is suitable for at least the plasma etch portion of the hybrid laser and etch singulation process 100 and may further deposit a polymer mask over the substrate. In one exemplary embodiment, the plasma etch chamber 608 is further coupled to an SF 6 gas source and at least one of a C 4 F 8 , C 4 F 6 , or CH 2 F 2 source. In a specific embodiment, the one or more plasma etch chambers 608 is an Applied Centura® Silvia™ Etch system, available from Applied Materials of Sunnyvale, Calif., USA, although other suitable etch systems are also available commercially. The Applied Centura® Silvia™ Etch system provides capacitive and inductive RF coupling for independent control of the ion density and ion energy than possible with capacitive coupling only, even with the improvements provided by magnetic enhancement. This enables one to effectively decouple the ion density from ion energy, so as to achieve relatively high density plasmas without the high, potentially damaging, DC bias levels, even at very low pressures (e.g., 5-10 mTorr). This results in an exceptionally wide process window. However, any plasma etch chamber capable of etching silicon may be used. In an embodiment, more than one plasma etch chamber 608 is included in the cluster tool 606 portion of integrated platform 600 to enable high manufacturing throughput of the singulation or dicing process.
[0054] The cluster tool 606 may include other chambers suitable for performing functions in the hybrid laser ablation-plasma etch singulation process 100 . In the exemplary embodiment illustrated in FIG. 6 , a mask module 614 includes any commercially available spin coating module for application of the water soluble mask layer described herein. The spin coating module may include a rotatable chuck adapted to clamp by vacuum, or otherwise, a thinned substrate mounted on a carrier such as backing tape mounted on a frame.
[0055] FIG. 7 illustrates a computer system 700 within which a set of instructions, for causing the machine to execute one or more of the scribing methods discussed herein may be executed. The exemplary computer system 700 includes a processor 702 , a main memory 704 (e.g., read-only memory (ROM), flash memory, dynamic random access memory (DRAM) such as synchronous DRAM (SDRAM) or Rambus DRAM (RDRAM), etc.), a static memory 706 (e.g., flash memory, static random access memory (SRAM), etc.), and a secondary memory 718 (e.g., a data storage device), which communicate with each other via a bus 730 .
[0056] Processor 702 represents one or more general-purpose processing devices such as a microprocessor, central processing unit, or the like. More particularly, the processor 702 may be a complex instruction set computing (CISC) microprocessor, reduced instruction set computing (RISC) microprocessor, very long instruction word (VLIW) microprocessor, etc. Processor 702 may also be one or more special-purpose processing devices such as an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a digital signal processor (DSP), network processor, or the like. Processor 702 is configured to execute the processing logic 726 for performing the operations and steps discussed herein.
[0057] The computer system 700 may further include a network interface device 708 . The computer system 700 also may include a video display unit 710 (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)), an alphanumeric input device 712 (e.g., a keyboard), a cursor control device 714 (e.g., a mouse), and a signal generation device 716 (e.g., a speaker).
[0058] The secondary memory 718 may include a machine-accessible storage medium (or more specifically a computer-readable storage medium) 731 on which is stored one or more sets of instructions (e.g., software 722 ) embodying any one or more of the methodologies or functions described herein. The software 722 may also reside, completely or at least partially, within the main memory 704 and/or within the processor 702 during execution thereof by the computer system 700 , the main memory 704 and the processor 702 also constituting machine-readable storage media. The software 722 may further be transmitted or received over a network 720 via the network interface device 708 .
[0059] The machine-accessible storage medium 731 may also be used to store pattern recognition algorithms, artifact shape data, artifact positional data, or particle sparkle data. While the machine-accessible storage medium 731 is shown in an exemplary embodiment to be a single medium, the term “machine-readable storage medium” should be taken to include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) that store the one or more sets of instructions. The term “machine-readable storage medium” shall also be taken to include any medium that is capable of storing or encoding a set of instructions for execution by the machine and that cause the machine to perform any one or more of the methodologies of the present invention. The term “machine-readable storage medium” shall accordingly be taken to include, but not be limited to, solid-state memories, and optical and magnetic media.
[0060] Thus, methods of dicing semiconductor substrates, each substrate having a plurality of ICs, have been disclosed. The above description of illustrative embodiments of the invention, including what is described in the Abstract, is not intended to be exhaustive or to limit the invention to the precise forms disclosed. While specific implementations of, and examples for, the invention are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. The scope of the invention is therefore to be determined entirely by the following claims, which are to be construed in accordance with established doctrines of claim interpretation. | Methods and apparatuses for dicing substrates by both laser scribing and plasma etching. A method includes laser ablating material layers, the ablating by a laser beam with a centrally peaked spatial power profile to form an ablated trench in the substrate below thin film device layers which is positively sloped. In an embodiment, a femtosecond laser forms a positively sloped ablation profile which facilitates vertically-oriented propagation of microcracks in the substrate at the ablated trench bottom. With minimal lateral runout of microcracks, a subsequent anisotropic plasma etch removes the microcracks for a cleanly singulated chip with good reliability. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a new method for obtaining conductive polymers that can be used to increase their conductivity and make it thermally stable.
The obtaining of high thermal stability then makes it possible to use such polymers for industrial purposes since their use generally necessitates steps in which a heating operation most usually leads to a decrease in their conduction.
2. Description of the Prior Art
At present, conductive polymers are obtained by several methods of synthesis.
The electrochemical method has been the one most studied since it can be used to synthesize polymers that perform well, but this type of synthesis generally results in the obtaining of a film and not a powder. The level of efficiency and the quantities inherent in this method of synthesis means that it is difficult to exploit it for industrial purposes. More precisely, the electrochemical method consists of an electropolymerization during which the polymer develops on an electrode and is made conductive by the insertion of ion species that stabilize the conduction. This mode of synthesis enables a great variety of polymerization both at the monomer level (pyrrole, thiophene, aniline, indole etc) and at the level of stabilizing species.
During the process of growth of the polymer on the anode, the oxidizing of the polymer leads to the creation of an electron defect (p type conduction). In the case of pyrrole, for example, this error is of the order of one hole for three heterocyclic structures. ##STR1##
The electrolyte A present gets dissociated and stabilizes the p type conduction, in forming a complex on the chain. The heat stability of the conduction of the conductive polymer then results mainly from the stability of the fixing of the anion.
The best results have been obtained on crude conductive polymer by means of paratoluene sulfonate, phenylsulfonate, alkylfluorosulfonate anions as compared with anions of low steric hindrance such as BF 4 - , PF 6 - , ClO 4 - . Furthermore, it would appear that the group RSO 3 has an electronegative potential greater than that of the anions BF 4 - , PF 6 - , ClO 4 - or RC00-: this furthers its quality of gripping in the polymer matrix.
At the same as the studies on the electrochemical method, work is being done on oxidative polymerization. This type of purely chemical synthesis brings a redox pair into play and enables the making of a conductive powder with submicronic sizes (1 μm to 0.1 μm), and achieves this result with excellent efficiency.
The reaction process generally brings together an oxidizing agent of the FeCl 3 , Fe(NO 3 ) 3 or CuCl 2 type, which will get reduced in the presence of a monomer.
Having been oxidized, the monomer gets polymerized in short chains (20 to 50 monomer units). The anion provided by the oxidizing agent behaves similarly to the anion of the electrolysis. For example, in the pair formed by pyrrole and ferric chloride, the oxidation-reduction reaction is as follows: ##STR2##
The chain thus synthesized therefore has anions of low hindrance and low electronegativity. The semiconductor powders are not very stable thermally and in relation to the oxidation. For example, polypyrrole powders cannot withstand being heated to more than 80° C. for some hours. Their conductivity drops to below 10 -3 s/cm, the threshold below which the process of elimination by diffusion of the anions becomes slower. This is also the case for polyaniline towards 120° C.
SUMMARY OF THE INVENTION
Since synthesis by a chemical method shows great promise in giving powders that can be used in processes of plastic technology and can be mixed with other bonder polymers, the present invention proposes a new method for obtaining conductive polymers that uses this chemical method while at the same time notably improving conductivity and its thermal stability.
This method comprises the introduction of electrochemically stable anions (cited in the description of synthesis by the electrochemical method), the low hindrance anions related to the oxidizing agent (for example the Cl - ions) being partially replaced by those with great hindrance such as the ones used in electropolymerization.
This new method therefore includes a first step of synthesis that is carried out in the presence of a monomer, an oxidizing salt and, in addition, a codopant salt having electrochemically stable anions. To provide thermal stability, the polymer thus obtained is heated to a temperature corresponding to the departure of the unstable anions from the oxidizing agent. The conductive polymer thus obtained henceforth contains only the stabilizing anions of the codopant in its matrix.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood more clearly and its other advantages shall appear from the following description, given on a non-restrictive basis, and from the appended figures, of which:
FIG. 1 shows the spectrum, in differential scanning calorimetry, of a codoped polymer powder;
FIG. 2 shows the spectrum, in differential scanning calorimetry, of a codoped polymer powder already heated to 150° C.;
FIG. 3 shows the changes in conductivity with time, at 60° C. for different mole ratios (codopant)/(oxidant),
FIG. 4 shows the changes in conductivity with time at 60° C., for different codopant anions.
DETAILED DESCRIPTION OF THE INVENTION
In the synthesis according to the method of the invention, the monomer is polymerized by the action of a standard oxidizing salt. It is preferably a transition metal salt.
During the oxidation reaction, a p type electron defect appears at the level of the monomer units. This defect is stabilized by the anion of the oxidizing salt.
For example, during the synthesis of polypyrrole in the presence of iron chloride FeCl 3 , the three monomers are stabilized by a Cl - ion. Analyses have shown that, in reality, the stabilizing anion is FeCl - . These anions are not, however, very stable for they tend to diffuse and escape from the polymer matrix. This is why the method according to the invention proposes the addition of a codopant salt to the monomer and to its polymerization triggering oxidizing agent. This codopant salt is preferably a quaternary ammonium salt or a sodium salt.
It is not responsible for the polymerization but, being present in the polymer network formed, it takes the place of the anions of the oxidizing salt when these unstable anions are exuded from the network. The pair formed by the oxidizing agent and the codopant agent can be used to obtain a conductive polymer, the conductivity of which is stabilized by the presence of the codopant anion which, by its nature, has a greater volume than that of the existing oxidizing anions. The codopant anion trapped in the matrix stabilizes the electron defects and is more heavily trapped in the matrix by virtue of its volume and is therefore diffused out of the matrix with far greater difficulty.
During the synthesis, an excess proportion of codopant agent is introduced into the reaction medium. During the heat treatment that succeeds the synthesis, when the temperature chosen is such that there is a departure of oxidizing anions, the codopant anions may compensate for the departure of these oxidizing anions.
This is why the codopant salts are chosen as a function of the possibilities of synthesis, the size of the anion and its electronegativity. In view of the promise shown by the sulfonate ions in electrochemical synthesis, the quaternary ammonium anions or sodium anions may be alkylsulfonates or alkylbenzenic sulfonates or CF 3 (CF 2 ) n SO 3 - or else again naphthylsulfonates.
The radical sulfonate is not chosen from among the macromolecules to avoid the obtaining of an anion of excessive volume which may cause an exaggerated deformation of the network and disturb the conductivity of the material. Indeed, the resultant conductivity is due not only to the polymeric intrachain conduction but also to the polymeric interchain conduction which would be hindered if the chains were to be at too great a distance from one another.
To validate these concepts, several syntheses have been made with codopant salts of a nature that is different, in terms of variable mole percentages, from the oxidizing salt. The conductivity of the synthesis products thus obtained has been studied in temperature and in time to analyze the phenomena of decrease of the conduction of these conductive polymers.
EXAMPLE A
This is the synthesis of polypyrrole in the presence of iron chloride. Several codopants have been experimented with.
1. Tetraethylammonium toluenesulfonate (marked Ts)
2. Tetraethylammonium heptadecafluorooctanesulfonate (marked F sulfo)
The cation of the codopant salt may, without distinction, be either quaternary ammonium or sodium, the results obtained being identical.
Several periods of synthesis have been experimented with (18 hours and 20 hours). It turns out that beyond 4 to 6 hours of reaction, the reaction rates are very low.
The use of salts of having a nature 1 or nature 2 induces the synthesis of two different powders. The first (Ts) is a fine powder that is easy to disperse, the second (F sulfo) is viscous and less easy to handle. However, both these two powders lead to a conductivity greater than that obtained in the absence of a codopant (Table I).
TABLE I______________________________________[Codopant]/[oxidizing agent] O [Ts]/[FeCl.sub.3 ] [Fsulfo]/[TeCl.sub.3 ]______________________________________T(s/cm) 1,15 4,78 2,9______________________________________
These are measurements of surface conductivity made by the method wherein four equidistant probe tips are used. They are made on powders pressed in identical conditions (namely mass of conductive polymer, pressure, duration and mold).
Furthermore, the thermal behaviour of a powder obtained from an oxidizing salt FeCl 3 and a codopant salt (ts) has been studied in order to arrive at a better understanding of the changes in conductivity as a function of the time and the temperature. By differential scanning calorimetry on a sample with a codopant salt Ts, two endothermic broad peaks are obtained, one between 60° C. and 50° C. corresponding to the eviction of the FeCl 4 - ions and a second one towards 150° C. characteristic of the presence of the tosylate ions (FIG. 1). Since the sample then undergoes a second thermal cycle, it thereafter displays only one high temperature broad peak relating to the remaining tolylate ions (FIG. 2). The phenomenon of diffusion of the codopant ions is sufficiently slow to keep a characteristic rate.
EXAMPLE B
Polypyrrole has been synthesized in the presence of FeCl 3 and of different mole percentages of (Ts).
FIG. 3 shows that there is an optimum ratio ranging from 0.5 to 1 for the mole ratio (Ts)/FeCl 3 .
The study in time has been done at 60° C. to illustrate the phenomena of decrease in conductivity. At this temperature, the decrease is about 40% in the presence of toluenesulfonate whereas it reaches 90% without a codopant agent. Furthermore, beyond 40 hours, the deterioration recorded in the presence of Ts gets stabilized whereas, in the absence of toluene sulfonate, the deterioration of the conductivity tends towards a zero value.
Similar behavior is observed when the synthesis of polypyrrole is done in the presence of FeCl 3 and (F sulfo) (FIG. 4).
The thermal treatment done in the region of 60° C., a temperature corresponding to the eviction of the FeCl 4 - ions from the polymer matrix, can be used to obtain a conductive polymer with conductivity that is far more stable in time, this being achieved for temperatures going beyond 60° C. | Disclosed is a novel method for obtaining conductive polymers enabling their conductive to be increased and thermally stabilized. The polymers are obtained by oxidative chemical process in the presence of a codopant, the anions of which are more stable than the oxidating anions. The synthesis of the polymer is furthermore followed by a thermal treatment operation by which the conductivity of the material obtained is stabilized. Application: microwave absorbents. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to microprocessor architecture and, in particular, to floating point register architecture.
2. Discussion of the Related Art
With the advent of more and more different types of computer systems and microprocessors, the number of different instruction sets for such systems continues to increase. Certain existing instruction sets, such as the x86 instruction set developed by Intel Corporation of Santa Clara, Calif. for its family of microprocessors, predominate the computer system market. Thus, by designing new microprocessors having the capability of operating with both an existing instruction set and an instruction set native to the new microprocessor, the value of the new microprocessor increases because the new microprocessor will be able to execute a wider range of applications. Native instructions are instructions that are decoded and executed by the processor directly. Because the x86 instruction set is so widely used for such a large number of applications, a major objective for developers of new microprocessors is to design their microprocessors or central processing units (CPUs) for compatibility with both the x86 instruction set and the computer's native instruction set.
The x86 instruction set is executed by complex instruction set computer (CISC) processors, while native instruction sets are typically executed by reduced instruction set computer (RISC) processors. For applications to run in either or both instruction sets, data and other information in floating point registers should be shared between RISC programs and CISC programs. Floating point numbers include a fraction or mantissa portion and an exponent portion. Formats for floating point data are typically wider than for integer data, e.g., 64 or 80-bit formats for floating point numbers compared to a 32-bit format for integers. CISC processors typically support a wider floating point format of 80 bits, while RISC only provides for a 64-bit format. Therefore, because of the different length formats for CISC and RISC processors, or similarly between x86 and native instruction sets, sharing data between the two data formats is not easily accomplished.
One way to share data and other information is to store the data in a register within the CPU before switching to the alternate instruction set and then to read the register by the instruction set. However, this requires that the registers be readable by either instruction set and that the instruction sets be extended to provide instructions to read the additional registers, thereby increasing the complexity and size of the CPU.
Another way to share data is to provide two sets of register stacks for the CPU, one set for the use of x86 instructions and a second set for the use of native instructions. Register stacks reside on the CPU die, which has a limited space available for registers. Thus, any additional registers require increasing the size of the CPU die or deleting functions of the CPU to free up die space for the additional stack. As a result, using two sets of register stacks increases size and cost and/or reduces efficiency of the computer system.
Accordingly, it is desired to have register stacks which support both CISC (e.g., x86 instructions) and RISC (e.g., native instructions) architectures for a dual-instruction-set CPU without the problems discussed above with respect to conventional methods.
SUMMARY OF THE INVENTION
According to the present invention, a floating point register stack combines pairs of data registers to form wider data registers such that different types of instruction sets with wider data formats can be supported. Thus, the resulting register stack can support both the processor's native instruction set and a wider instruction set, such as the x86 instruction set. Instructions map 80-bit x86 instructions into two 64-bit native general purpose registers to provide the required functions of an x86 floating point stack, which allows the processor greater flexibility to run an greater number of operations and applications.
The present invention will be more fully understood in light of the following detailed description taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows blocks for an x86 FPU execution environment;
FIG. 2 shows two 64-bit registers paired to produce a register capable of an 80-bit format;
FIG. 3 shows blocks for a multi-media execution environment having the ability to support x86 instructions;
FIGS. 3A and 3B show the pseudo-tag register and stack map register, respectively, of FIG. 3;
FIG. 4 is a block diagram of an implementation for x86 register stack management; and
FIGS. 5A and 5B show examples of some x86 operations carried out using the present invention.
Use of similar reference numbers in different figures indicates similar or like elements.
DETAILED DESCRIPTION
A computer processor unit (CPU) can employ a stack for managing data, such as a floating point unit (FPU) register stack. FIG. 1 shows an x86 FPU execution environment, which includes a register stack 10 , a control register 11 , a status register 12 , a tag register 13 , an instruction pointer 14 , a data pointer 15 , and an opcode register 16 . FPU register stack 10 is an array of eight 80-bit data registers R 0 to R 7 that store data in extended-real format. When integer or floating point data is loaded from memory into any one of registers R 0 to R 7 , the data is converted to extended-real format, which is 80 bits in size, with a 64-bit mantissa or significand, a 15-bit exponent, and one sign bit. The exponent is biased for single and double precision formats so that a separate sign bit for the exponent is not needed. Integer data formats are typically 32-bits in width or size, while floating point formats include more bits of precision by having a significand of 24, 53 or 64 bits. The range of these floating point formats is also increased by having exponents of 8, 11, or 15 bits. Standard or single-precision floating point uses 32 bits, with a sign bit, an 8-bit exponent, and a 23-bit mantissa. The double-precision floating-point format uses 64 bits, with a sign bit, an 11-bit exponent, and a 52-bit mantissa. RISC processors use both single and double precision floating point formats. CISC processors use these formats in addition to the extended-real precision. When data is transferred back to memory, the data is converted back to the original format, i.e., integer, single, double, or extended-precision.
Control register 11 is a 16-bit register for controlling the precision and rounding modes for x86 floating point instructions. Status register 12 is a 16-bit register which indicates the current state of the FPU and includes the FPU busy flag, top-of-the-stack (TOS) pointer, floating point condition code flags, error summary status flag, stack fault flag, and exception flags. Tag register 13 is a 16-bit register for keeping track of the contents of each of the eight FPU data registers R 0 to R 7 . Tag register 13 is divided into eight 2-bit portions, each 2-bit portion representing a data register, with register R 0 represented by the two least significant bits and register R 7 represented by the two most significant bits. Each 2-bit portion indicates whether the associated register is empty or not and the type of data within the register. Instruction pointer 14 and data pointer 15 are located in 48-bit registers. Instruction pointer 14 contains a pointer to the last non-control floating point instruction executed, and data pointer 15 contains a pointer to the data operand for the last non-control floating point instruction executed. Opcode register 16 is an 11-bit register containing the opcode of the last non-control floating point instruction. Additional details about the x86 FPU execution environment can be found in Intel Pentium Processor Manuals, available through Intel Corporation of Santa Clara, Calif.
FPU instructions address the data registers relative to the top of the stack (TOS). Special instructions facilitate accessing the desired data in register stack 10 . For storing or writing new data from memory to register stack 10 , the TOS pointer is first decremented by a “decrement” instruction to the next unoccupied register location and then data is “pushed” onto this unoccupied location by a “push” instruction. For example, if register R 4 is at the top of the stack, TOS pointer is decremented to point to register R 3 , and data is written into register R 3 , which is now the top of the stack. Data can be pushed onto the registers until register R 0 is reached and written into. The next attempt to write data into register stack 10 results in a stack overflow exception.
For reading data off the top of the stack (or storing data from the top of the stack to memory), data is read or “popped off” at the location pointed to by the TOS pointer by a “pop” instruction. The TOS pointer is then incremented by an “increment” instruction to point to the previous data in the stack, which is now the new top of the stack. For example, if the top of the stack is register R 3 , the data in register R 3 is read and stored into memory. The TOS pointer is incremented to point to register R 4 which is the new top of the stack. When a pop instruction causes the TOS pointer to point to an empty register, a stack underflow exception occurs.
Most x86 instructions require both reading and writing at the top of the register stack, and once the result of the floating point instruction is obtained, the result is written to the top of the stack. The result then needs to be moved off the register at the top of the stack so that data from another register can be moved to the top of the stack for the next instruction. As a result, operands or data may need to be moved regularly to and from the register at the top of the stack. A floating point exchange (FXCH) instruction exchanges contents of the register at the top of the stack with the contents of a register at another portion of the stack. The FXCH instruction is useful because exchanging the contents of two registers can be performed with one instruction, thereby increasing efficiency and throughput. For example, data can be moved from register R 4 to the top of the stack and from the top of the stack to register R 4 with a single FXCH instruction. Because the FPU register stack for x86 instructions consists of only eight registers, the FXCH instruction is needed to allow data to be moved into and out of the stack so that desired operations can be performed.
Whereas CISC processors use 80-bit registers to read and write x86 instructions, RISC processors typically only use 64-bit general purpose registers to execute native instructions. Therefore, for processors designed with only 64-bit registers, a register stack management is desired so that these processors can also accommodate x86 instructions requiring 80-bit registers.
FIG. 2 shows two 64-bit registers paired to produce a register capable of 80-bit extended precision format. For 80-bit extended precision, the 64 bits of the significand or mantissa are completely stored in one register. The 15 bits of the exponent and the one sign bit are stored in the 16 lowest bit positions of the paired register. The remaining 48 bits of the 64-bit paired register are unused, although other information could be stored in these 48 unused bit positions.
FIG. 3 shows a multi-media FPU execution environment capable of supporting x86 programs, which includes a register stack 30 , a control register 31 , a status register 32 , a pseudo-tag register 33 , a data pointer 34 , a stack-map register 35 , and an opcode register 36 . The multi-media register set includes sixty-four 64-bit general purpose registers GPR 0 to GPR 63 . Since there are only eight 80-bit x86 floating point registers, pairing two multi-media registers for each x86 register requires only sixteen of the sixty-four multi-media floating point data registers. Another eight of the general purpose registers are used for the x86 integer general purpose registers. The remaining forty registers include a hard-wired zero, a call/return linkage register, and registers for hardware (conversion) and software temporaries.
In multi-media register stack 30 , registers GPR 32 to GPR 47 are designated for x86 instructions, where successive registers are paired together and where the odd register is used for the 64-bit mantissa and the even register is used for the 15-bit exponent and one-bit sign. As shown in FIG. 3, multi-media register stack 30 pairs together registers GPR 32 and GPR 33 to map into x86 register R 7 of FIG. 1, through to registers GPR 46 and GPR 47 to map into x86 register R 0 . The x86 operands or data are loaded or stored into the pair of multi-media registers by first checking the lowest 16 bits of the even register for exceptions and then loading or storing the 15-bit exponent and one-bit sign into the 16 lowest bit positions of the even register, followed by loading or storing the 64-bit mantissa into the odd register.
16-bit control register 31 and status register 32 , 48-bit data pointer 34 , and 11-bit opcode register 36 are similar to control register 11 , status register 12 , data pointer 15 , and opcode register 16 , respectively, for the x86 execution environment of FIG. 1 . Data pointer 34 contains a pointer to the memory operand of the last FP x86 instruction. The 48-bit pointer consists of a 16-bit selector and a 32-bit offset in the data segment. Opcode register 36 contains the 11-bit opcode of the last FP x86 instruction.
Pseudo-tag register 33 , shown in FIG. 3A, is an 8-bit register containing one bit for each of the eight paired registers in stack 30 , according to one implementation. The lowest bit represents register R 0 at the top of the stack, and the highest bit represents register R 7 at the bottom of the stack. The bit corresponding to each register denotes whether the corresponding data register is empty or not and is used to detect stack overflow and underflow exceptions. Stack-map register 35 , shown in FIG. 3B, is a 24-bit register for mapping x86 data registers to the general purpose data registers. Stack-map register 35 contains eight 3-bit elements, with each element representing an x86 data register R 0 to R 7 . The lowest 3-bit element represents the register at the top of the stack, and the highest 3-bit element represents the register at the bottom of the stack. Every stack element can be mapped into one of eight general purpose registers, as designated by the three bits in each 3-bit element.
FIG. 4 is a block diagram of an implementation for x86 register stack management. A converter 40 receives variable length x86 instruction bytes (x86_instn), converts them to a sequence of fixed length native multi-media instructions, and determines the location of the two x86 sources in the x86 FPU register stack to be used for execution of the x86 instruction. Converter 40 also maps the x86 stack to the general purpose registers. The x86 FPU stack identifier for the first source (x86_src 1 ) is then used as an input to an 8:1 multiplexer 41 to select the 3-bit element from stack map register 35 corresponding to the first source identifier. For example, if the data or operand in data register R 1 (top of the stack minus one) is identified by the first source identifier as the first source of the x86 instruction, multiplexer 41 outputs 001 as the multi-media floating point GPR identifier for the first source (fp_src 1 ). Converter 40 then accesses the location designated by fp_src 1 for use by the issuer. Similarly, the x86 FPU stack identifier for the second source (x86_src 2 ) is used as an input to an 8:1 multiplexer 41 to select the 3-bit element from stack map register 35 corresponding to the second source identifier. The multi-media floating point GPR identifier for the second source (fp_src 2 ) is then used by converter 40 to obtain the second source for the x86 instruction.
The x86 FPU stack identifiers x86_src 1 and x86_src 2 are also used as inputs to 8:1 multiplexers 42 to select the 1-bit element from pseudo-tag register 33 corresponding to the register identified by x86 src 1 and x86_src 2 . These 1-bit elements, along with stack identifiers x86_src 1 and x86_src 2 and the desired stack operation for each register, are then input to a stack exception logic 43 . The stack identifier and the desired stack operation inputs are used to determine which 1-bit element from multiplexer 42 is associated with which stack operation. Stack exception logic 43 then compares each of the 1-bit elements with its corresponding stack operation to detect whether a stack exception exists for the desired operation, i.e., if no stack exceptions exist, then there are valid operand(s) for the desired operation. For example, if x86_src 1 indicates that the x86 instruction requires a push operation on data register R 0 and pseudo-tag register 33 indicates that register R 0 is not empty, stack exception logic 43 will determine that a stack overflow exception exists, or if x86_src 2 indicates that the x86 instruction requires a pop operation on data register R 7 and pseudo-tag register 33 indicates that register R 7 is empty, stack exception logic 43 will determine that a stack underflow exception exists.
The 3-bit elements from stack-map register 35 and the 1-bit elements from pseudo-tag register 33 are also input to a stack-map and pseudo-tag logic 44 . Instructions to carry out x86 operations, such as inc/dec, pop, ffree, FXCH, push, and set, are also input to logic 44 . Logic 44 operates on the stack elements. The inc/dec operations increments/decrements the top of stack pointer by one. The pop operation removes an operand from the stack, the ffree operation marks an arbitrary element as empty, and the FXCH operation swaps two stack elements. The push operation adds a new operand to the stack, and the set operation marks an arbitrary element as non-empty. FIG. 5A shows some examples of manipulation of map pointers for stack operations, and FIG. 5B shows some examples of valid bit manipulation of stack operations.
The above-described embodiments of the present invention are merely meant to be illustrative and not limiting. For example, although the above-described embodiments were with reference to a multi-media processor, other types of operating environments and processors may also be suitable for use with this invention. It will thus be obvious to those skilled in the art that various changes and modifications may be made without departing from this invention in its broader aspects. Therefore, the appended claims encompass all such changes and modifications as fall within the true spirit and scope of this invention. | A floating point register stack for a processor combines a plurality of two general purpose registers to form a register stack for x86 instructions and leaves the remaining general purpose registers for native instructions of the processor. By mapping x86 sources into the stack of two general purpose registers and operating x86 instructions on the x86 stack, the register stack for the processor is able to support both the processor's native instruction set and the x86 instruction set without increasing the size of the register stack. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a dough divider or delivery assembly of the type specifically designed to remove individual dough portions in predetermined quantities from a common supply of dough and the delivery of such dough portions to a delivery site such as a conveyor belt wherein further processing is accomplished.
2. Description of the Prior Art
Conventionally, dough is divided into equal volumetric portions from a main or common supply of dough wherein such portions are rolled into balls and deposited into pans for further baking, processing, etc. The prior art is replete with rotary dough dividers used to accomplish this purpose as evidenced by the following U.S. Pat. Nos. to Steere, 1,954,501; Marasso, 2,858,775; Atkins, 3,541,974; and Cummuns, 4,391,576.
Typical of prior art structures is the assembly disclosed in the above noted patent to Cummons which is directed to a rotary drum dough divider. More specifically, Cummuns discloses an improved assembly for use in a cylinder of a rotating drum type dough divider comprising a sleeve positioned in the cylinder forming seals on both sides of a pair of diametrically opposed guide slots connected to atmosphere and a pair of ducts communicating with the cylinder at opposite ends of the sleeve which are alternately connected to pressure and vacuum. A double acting piston having a head at each end of the cylinder and a piston rod portion extending from each head into the sleeve, and a scaling rod joining the adjacent ends of the piston rod pushes together as provided. Such piston portions reciprocate to cause the rod portions and their heads to reciprocate together in the cylinder instead of by serving as a double ended cylinder and alternately open and closing opposite open ends of the cylinder for the receiving and dispensing of dough therein.
Typical to the problems associated with the prior art and recognized in the industry is the provision of a negative pressure or vacuum to the open end of the cylinder from a locale which is internal of the rotary drum. While the vacuum pump itself may physically by located externally of the rotating drum, connection of the negative fluid pressure source into the interior of the drum such that such negative pressure is drawn through the piston ends. Accordingly, when the open end or ports in the rotating drum is exposed to the supply of dough within a retaining hopper the dough portions in proper volumetric sizing are "sucked" into the exposed port and carried therewith to a delivery site. One problem commonly recognized with these prior art devices is the clogging or scaling of dough beyond the piston head due to the existence of negative pressure on the interior of the cylinder, internally of the location of the piston head. More specifically, after prolonged and continuous operation the dough being brought into the ports through the open ends thereof "leaks" into passages serving to connect the internal negative pressure source to the outer side of the piston. This in turn requires an at least partial dismantling of the assembly and a downtime of the machine in order that such inwardly scaled or leaked dough is removed therefrom. Failure to conduct such maintenance results in a loss of vacuum or negative pressure and failure of the volumetric portions to be brought into the open ended ports or pockets in the proper quantities. Inconsistency in the end product is the obvious result.
Accordingly, there is a need in this industry to provide a means of applying a negative pressure or vacuum to the ports immediately prior to their exposure to the common supply of dough in a manner which will eliminate the clogging of the dough or passage thereof beyond the piston heads into the integral or interior parts of the cylinder so that maintenance and downtime is eliminated or significantly reduced due to this problem.
SUMMARY OF THE INVENTION
The present invention relates to a delivery system specifically designed to remove pre-measured portions of dough from a common or central supply of dough, maintained in a retaining hopper and deliver such dough portions to a conveyor belt for carrying to further processing step. An important feature of the present invention is the provision of a pressurizing means used in combination with the dispensing means. The dispensing means, set forth above is preferably in the form of a cylinder structure having an external cylindrical surface configuration defining an outer operative surface in which a plurality of ports are formed to extend radially inward toward the center of the cylinder. Piston heads are reciprocally mounted within the ports and positionable between an open and closed position. The open position of each piston and its associated cylinder is defined by a recessed disposition of the cylinder head relative to the open end of the port contiguous to the outer operative surface of this cylinder. In such position a pocket is formed of known dimension wherein such pocket is exposed to the supply of dough for receipt of the aforementioned predetermined portion of dough therein. Continuous rotation of the cylinder thereby successively delivers the plurality of pockets from the supply of dough, at which location a portion of dough is received, to a delivery site. The delivery site is defined by a conveyor belt wherein the dough portions are carried thereby to different processing locations.
To facilitate the above process, the subject invention incorporates pressurizing means, as set forth above, used in combination with and in direct exposed cooperation to the outer surface of the dispensing cylinder. This pressurizing means comprises a "cap" or hood structure having an open face and a seal means mounted thereon. The open face is disposed to have a configuration substantially corresponding to the exterior configuration of the outer surface of the cylinder so as to be disposed in cooperative and specifically, fluid communication therewith. The seal means is disposed on the open face of the cap structure in engagement with the outer surface of the cylinder as it rotates. The seal means may be formed from a material commercially available under the trademark Dura-Seal which allows for the continuous rotation or sliding movement of the outer surface on the seal means while maintaining a fluid tight seal therebetween.
The pressurizing means further comprises a vacuum pump, which may be a substantially conventional design but which is interconnected to the cap structure in direct fluid communication with the open face thereof. A negative pressure is applied directly to the portion of the outer surface of the cylinder covered by the cap structure and effectively surrounded by the seal means on the open face of the cap structure. Naturally, due to the maintenance of the negative pressure over the outer surface of the cylinder such negative pressure will also be exposed to the ports when the piston head moves to the aforementioned open position. Therefore, the interior of the ports or pockets will be maintained under a negative pressure as these ports or pockets pass successively and continuously into direct exposure with the dough supply maintained within a supply hopper. The existence of the vacuum or negative pressure within the ports causes the dough to be "sucked" into the individual ports or pockets therefore serving to automatically measure out the portions of dough for delivery and dispensing at the delivery site or conveyor belt. The continued rotation of the cylinder thereby successively passes the ports, after being filled, from the supply of dough and the supply hopper to the delivery site. At this locale the piston heads within the respective cylinder, due to the existence and incorporation of mechanical linkage, known to the prior art, serves to move the piston head to the closed position thereby forcing the individual dough portions from their respective cylinder and allowing them to be dispensed at the delivery site.
Accordingly, an important feature of the present invention is a specific application of a negative pressure or vacuum to the operative outer surface of the cylinder and specifically to the ports to induce a negative pressure therein from an exterior location in order to prevent any clogging or scaling of the dough into the interior of the cylinders beyond the piston heads as is common in prior art machinery and procedures.
The invention accordingly comprises the features of construction, a combination of elements, and an arrangement of parts which will exemplified in the construction hereinafter set forth, the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the nature of the present invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:
FIG. 1 is a schematic representation of the assembly of the present invention used in cooperation with a delivery site preferably in the form a conveyor belt to convey or carry formed dough portions to other processing steps not specifically associated with the present invention.
FIG. 2 is a detailed respective view of a pressurizing assembly associated with the structure of the present invention and having a mountin gbracket or like structure used therewith.
FIG. 3 is a schematic representation showing relative movement of the pressurizing structure of FIG. 2 relative to its operative position.
FIG. 4 is a sectional view in partial cut-away showing internal details of the dispensing cylinder and piston heads associated with opposed ports.
FIG. 5 is a prospective view showing details of the dispensing cylinder, ports formed therein and piston heads associated with the various ports.
Like reference numerals refer to like parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1 the assembly of the present invention is generally indicated as 10 and comprises a dispensing means in the form of a dispensing cylinder 12 mounted to rotate in accordance with the directional arrow 13 in a continuous fashion during operation of the assembly 10. The cylinder 12 includes an outer cylindrical operative surface 14 having a plurality of ports formed therein and extending radially inward from the outer surface 14 inwardly toward the center of the cylinder. With reference to FIGS. 1 and 3 each of the ports 16 and accordingly their opened ends 18, due to the rotation of the cylinder 12 successively passes into exposure and registry with a pressurizing means generally indicated as 20 to be described in greater detail hereinafter and a supply of dough maintained within the supply hopper or retainer generally indicated as 22. Next, and again due to the rotation of the cylinder 12 the outer surface 14 and the ports 16 are passed from the supply hopper 22 to a delivery site generally indicated as 24 and schematically represented in FIG. 1 as a conveyor assembly in the form of a conveyor belt 26 driven by one or more drive rollers 28. The conveyor belt 26 delivers the preformed volumetric portions of dough to additional processing steps not specifically associated with the present invention.
From a review of FIGS. 4 and 5 it is noted that each of the ports 16 have reciprocally mounted therein a piston head 30 such that the piston head moves in between an open and closed position relative specifically to the opened end 18 of each of the ports. The reciprocal movement of the piston head 30 within its respective port is accomplished by mechanical linkage which may be of conventional design and manufacture and depended upon the rotation of the dispensing cylinder 12 (see FIG. 4). The piston head moves between its open and closed position based on its disposition relative to the dispensing means 20, the supply hopper 22 (and exposure to dough therein) and the delivery site 24. Further, the aforementioned open position of the piston head within its respective cylinder may be defined by an inward recessed disposition of the piston head 30 away from the open end thereby forming a pocket in each of the ports 16 for the reception of a portion of dough therein from the supply maintained within the supply hopper 22. The closed position of the piston head (see FIG. 4), as set forth above, is defined by the outer positioning or extension of the piston head into substantially flush or contiguous relation to the outer surface 14 of the dispensing cylinder 12 such that any dough portion contained within the pocket of the respective ports is dispensed therefrom as the piston head moves to its closed position as set forth above. Therefore, dispensing of any dough from the pocket within the respective ports is accomplished by the automatic positioning of the piston head from its open position to its closed position. This forces the dough portion onto the conveyor belt which, in the preferred embodiment described, defines a portion of the delivery site 24.
With reference to FIGS. 1, 2 and 3 the pressurizing means 20 comprises a cap structure 34 having an opened face (see FIG. 2) generally indicated as 36 which preferably has a concave configuration corresponding to the configuration of the outer cylindrical surface 14 of the dispensing cylinder 12.
With reference to FIGS. 1 and 2 it should be noted that the pressurizing means 20 further comprises a vacuum pump 38 which may be of conventional design and connected by an appropriate conduit as at 39 to the cap structure 34 and more specifically to direct exposure and fluid communication with the open face 36 as by opening 42.
In addition, the open face 36 includes a seal means preferably in the form of an at least partially peripherally located sealed gasket 44 extending about the periphery of the open face 36 and specifically about the opening 42 thereof. The seal means in the form of gasket 44 may be formed from the material commercially available under the trademark "Dura-Seal" and is specifically structured and disposed to engage the rotating outer surface 14 of the dispensing cylinder 12.
Another embodiment of the present invention also incorporated in the structure of FIG. 2 includes lubricating means in the form of a lubricating head or opening 46 including a lubricant disbursing structure generally indicated as 48 communicating, through proper conduit 49, to a supply of lubricant schematically represented as 52. The lubricant of course is in the form of an acceptable oil to come in direct contact with the dough product maintained within the hopper 22 so as not to contaminate the dough while at the same time reducing friction between the outer surface 14 of the dispensing cylinder 12 and any portions such as the open face 36 and seal gasket 44 of the pressurizing means 28 as well as the dough or any cooperating structure associated with the supply hopper 22.
Yet another embodiment of the present invention is also shown in FIGS. 2 and 3 and comprises a mounting assembly 56 secured to preferably an upper end of the cap structure 34 and including at least one or more hinge structures 58 disposed in spaced apart relation to one another. Each of the hinge structures 58 include a pivot pin 60 extending between upstanding ears 62 formed on the cap structure 34 and affixed thereto. Similar depending ears 64 are disposed to extend down between the ears 62 and also allow for the passage of the pivot pin 60 therethrough. By virtue of this interconnection it is readily seen that the cap structure 34 is pivotal relative to the mounting bracket 56 as schematically represented by directional the arrows in FIG. 3. Therefore, while a fluid type or sealed engagement occurs between the sealed means or the gasket 44 in the outer surface 14 of the dispensing cylinder 12 such engagement may in fact be "floating" or clearly adjustable to provide for any inconsistencies in the cylindrical outer surface 14 or adjustment or displacement in the disposition of the cylinder head 12. Also as further represented by directional arrow 66 the bracket 56 may be adjusted by mechanical linkage generally indicated as 69 in FIG. 1. The mechanical linkage serves to interconnect the mounting bracket 56 and the supported vacuum cap 34 in its operative fashion and may be adjusted based upon the changing of the dispensing cylinders 12 inside or placement. A support bracket 72 serves to connect and support the mechanical linkage 69 is also clearly shown in FIG. 1.
Therefore in operation the dispensing cylinder 12 serves to continuously rotate and by virtue of this rotation passes the outer cylindrical surface 14 as well as the ports therein successively into registry and cooperation with the pressurizing means 20, the dough within the supply hopper 22, and the delivery site 24. The rotation of the cylinder 12 is associated with the mechanical linkage of FIG. 4 to dispose, automatically, the piston heads 30 between the aforementioned and defined closed and open positions. Such linkage is arranged such that when the ports are in underlying, covered relation by the vacuum cap structure 34, the piston heads are in the open position relative to the open end 18 of the port 16 in order that the negative pressure, applied to the outer surface 14 as well as the port 16, will cause a vacuum within the ports. While this vacuum is maintained and the piston heads remain in their open position, the rotation of the cylinder 12 will position the open, negative pressurized ports 16 into receiving relation with the dough supply within the supply hopper 22 such that individual dough portions may be "sucked" into the individual pockets of the ports as discussed above. As the cylinder continues to rotate and the filled ports pass from the dispensing hopper 22 the pistons may be gradually and automatically disposed into their closed position thereby forcing the dough portions out from their respective pockets or ports onto the conveyor belt 26 representing and defining the delivery site 24. | A dough delivery or divider assembly having a plurality of ports integrally formed in a cylindrical dispensing structure and incorporating an external pressurizing structure wherein a negative pressure or vacuum is applied to the interior of each of the ports from an exterior location relative to the cylindrical surface in which the ports are formed. The vacuum is maintained within the ports until they are exposed to the supply dough within a supply hopper wherein the negative pressure aids forcing of the dough into the ports for transportation to a delivery site at which location the dough portions are removed from the ports. | 8 |
FIELD OF THE INVENTION
The present invention relates to a method for monitoring the supply of substitution fluid for an apparatus for extracorporeal blood treatment with an extracorporeal blood circuit, which comprises a first chamber of a dialyzer or filter divided by a membrane into the first chamber and a second chamber, and a fluid system which comprises the second chamber of the dialyzer or filter. Moreover, the present invention relates to a device for monitoring the supply of substitution fluid for an apparatus for extracorporeal blood treatment as well as an extracorporeal blood treatment apparatus with a monitoring device for the supply of substitution fluid.
BACKGROUND
Various methods for extracorporeal blood treatment or cleaning are used to remove substances usually eliminated with urine and for fluid withdrawal. In hemodialysis, the patient's blood is cleaned outside the body in a dialyzer. The dialyzer comprises a blood chamber and a dialyzing fluid chamber, which are separated by a semipermeable membrane. During the treatment, the patient's blood flows through the blood chamber. In order to clean the blood effectively from substances usually eliminated with urine, fresh dialyzing fluid flows continuously through the dialyzing fluid chamber.
Whereas the transport of the lower-molecular weight substances through the membrane of the dialyzer is essentially determined by the concentration differences (diffusion) between the dialyzing fluid and the blood in the case of hemodialysis (HD), substances dissolved in the plasma water, in particular higher-molecular weight substances, are effectively removed by a high fluid flow (convection) through the membrane of the dialyzer in the case of hemofiltration (HF). In hemofiltration, the dialyzer functions as a filter. Hemodiafiltration (HDF) is a combination of the two processes.
In hemo(dia)filtration, part of the serum drawn off through the membrane of the dialyzer is replaced by a sterile substitution fluid, which is generally fed to the extracorporeal blood circuit either upstream of the dialyzer or downstream of the dialyzer. The supply of substitution fluid upstream of the dialyzer is also referred to as pre-dilution and the supply downstream of the dialyzer as post-dilution.
Apparatuses for hemo(dia)filtration are known, wherein the dialyzing fluid is prepared online from fresh water and dialyzing fluid concentrate and the substitution fluid is prepared online from the dialyzing fluid.
In the known hemo(dia)filtration apparatuses, the substitution fluid (substituate) is fed to the extracorporeal blood circuit from the fluid system of the machine via a substituate supply line. With pre-dilution, the substituate line leads to a connection point on the arterial blood line upstream of the dialyzer or filter, whereas with post-dilution the substituate line leads to a connection point on the venous blood line downstream of the dialyzer or filter. The substituate line comprises for example a connector with which it may be connected either to the venous or arterial blood line. In order to interrupt the fluid supply, a clamp or suchlike is provided on the substituate line. A hemo(dia)filtration apparatus of this kind is known for example from European Patent Publication No. EP 0 189 561.
The effectiveness of the blood treatment depends on whether the substitution fluid is fed to the extracorporeal blood circuit upstream or downstream of the dialyzer or filter. A knowledge of the mode of treatment, i.e., pre- or post-dilution, is therefore important.
European Patent Publication No. EP 1 348 458 A1 describes a method and a device for monitoring the supply of substitution fluid for an extracorporeal blood treatment apparatus. The propagation time of the pressure waves of a substituate pump disposed in the substituate line is measured in order to detect the supply of substitution fluid upstream or downstream of the dialyzer or filter. The supply of substituate upstream or downstream of the dialyzer or filter is detected on the basis of the propagation measurement. The known method requires the use of a substituate pump generating pressure waves.
There is known from German Patent Publication DE 10 2004 023 080 A1 a device for monitoring the supply of substitution fluid, wherein the supply of substituate upstream or downstream of the dialyzer or filter is detected on the basis of the change in the pressure, for example on the basis of a sudden pressure rise and/or pressure drop after the substituate pump is switched off or switched on. The known method requires the use of a substituate pump generating pressure waves.
A goal of example embodiments of the present invention is to provide a method for monitoring the supply of substitution fluid, which permits the detection of pre- or post-dilution with a high degree of reliability. Moreover, it is a goal of example embodiments of the present invention to provide a device for monitoring the supply of substitution fluid, with which the pre- and post-dilution may be reliably detected. A further goal of example embodiments of the present invention is to create an extracorporeal blood treatment apparatus with such a monitoring device.
SUMMARY
The method according to example embodiments of the present invention and the device according to example embodiments of the present invention for the detection of pre- or post-dilution is based on the measurement and monitoring of the density of the blood or a blood constituent in the extracorporeal circuit. When there is a change in substitution rate Q S at which substitution fluid is fed to the blood in the extracorporeal circuit, and/or blood flow rate Q B at which blood is fed to the first chamber of the dialyzer or filter and/or flow rate Q M at which fluid is withdrawn from the blood via the membrane of the dialyzer or filter, the density of the blood or the blood constituent in the extracorporeal blood circuit changes. It has been shown that the amount and/or the direction of the change, i.e., an increase or reduction in the density by a specific value, depends on whether the substitution fluid is fed to the blood upstream or downstream of the dialyzer or filter. It is then concluded that there is a pre-dilution or post-dilution on the basis of the change in the density of the blood or the blood constituent. Change in density is also understood in this sense to mean the change in concentration of a blood constituent such as for example hemoglobin.
The method according to example embodiments of the present invention and the device according to example embodiments of the present invention in principle require only the single change in substitution rate Q S and/or blood flow rate Q B and/or flow rate Q M at which fluid is withdrawn from the blood via the membrane of the dialyzer or filter. Since the pre- or post-dilution is to be monitored during the blood treatment, which is preferably to be carried out at specific fluid rates Q S , Q B and/or Q M , a preferred embodiment makes provision, after the reduction or increase in at least one of the three fluid rates by a preset amount for a preset time interval, which should be as short as possible, for an increase or reduction again after the lapse of the preset time interval by a preset amount, which in particular corresponds to the amount by which the corresponding fluid rate or the fluid rates has or have been previously reduced or increased, so that the blood treatment may be continued at the same fluid rates. Flow rate Q M withdrawn from the blood is reduced or increased preferably simultaneously in the same time interval preferably by the same amount and, after the lapse of the preset time interval, preferably increased or reduced again by the same amount as substitution rate Q S .
When mention is made below of a change in the flow rate, this may also be understood to mean a reduction in the flow rate by an amount such that the flow rate is zero, i.e., the flow is interrupted.
The amount by which a flow rate is reduced or increased is in principle irrelevant for the detection of pre- or post-dilution. The decisive factor, however, is that a change in the density can be detected selectively for pre- and post-dilution with sufficient reliability.
The method according to example embodiments of the present invention and the device according to example embodiments of the present invention provide different embodiments, which differ from one another by the point of the extracorporeal blood circuit at which the density of the blood or the blood constituent is measured.
A pre- or post-dilution may be detected by a measurement of the density downstream of the point of the extracorporeal blood circuit at which substitution fluid is fed to the blood circuit in the case of a pre-dilution and upstream of the first chamber of the dialyzer or filter. It is also possible to detect a pre- or post-dilution by a measurement of the density downstream of the first chamber of the dialyzer or filter and upstream of the point of the blood circuit at which substitution fluid is fed to the blood circuit in the case of post-dilution. The density may also be detected by a measurement downstream of the point of the blood circuit at which substitution fluid is fed to the blood circuit in the case of post-dilution. It may be decisive that the density is measured immediately after the change in the respective flow rate, since a change in the density may be detected only within a specific time interval, depending on the measurement position. The reason is that, in these cases, the density may reassume its original value after the lapse of this time interval.
It has been shown that the change in substitution rate Q S , with a simultaneous change in flow rate Q M at which fluid is removed from the blood via the membrane of the dialyzer or filter, leads to notably different changes in the density at different points of the extracorporeal circuit. For example, the density may increase or decrease depending on a pre- or post-dilution.
In a first example embodiment, substitution rate Q S is reduced by a preset amount and the density is measured in the blood circuit downstream of the point of the blood circuit at which substitution fluid is fed to the blood circuit in the case of pre-dilution and upstream of the first chamber of the dialyzer or filter. The density of the blood or blood constituent before the reduction in substitution rate Q S and after the reduction in substitution rate Q S are then compared with one another, it being concluded that there is a supply of substitution fluid upstream of the dialyzer or filter if the density after the reduction of the substitution rate has increased by a preset amount. If the density of the blood after the reduction in the substitution rate has not increased by a preset amount, it is concluded on the other hand that there is a supply of substitution fluid downstream of the dialyzer or filter.
The method according to the invention and the device according to the invention do not in principle require the measurement of the density of the blood both before and after the reduction in the substitution rate. It may, in principle, be sufficient to measure the density only after the reduction in the substitution rate, in order to compare the measured value with a characteristic threshold value.
A particularly preferred example embodiment with a particularly significant change in the density of the blood provides for a measurement of the density of the blood or blood constituent in the blood circuit downstream of the point of the blood circuit at which substitution fluid is fed to the blood circuit in the case of post-dilution. After a comparison of the density before and after the reduction in substitution rate Q S and preferably a simultaneous reduction in flow rate Q M , it is concluded that there is a supply of substitution fluid upstream of the dialyzer or filter if the density after the reduction in substitution rate Q S has diminished by a preset amount. It is concluded that there is a supply of substitution fluid downstream of the dialyzer or filter if the density after the reduction in substitution rate Q S has increased by a preset amount.
The increase in the density of the blood or the blood constituent in the case of post-dilution is due to the fact that, immediately after the reduction in substitution rate Q S at which the substitution fluid is fed to the blood and the simultaneous reduction in fluid rate Q M at which fluid is withdrawn from the blood via the membrane of the dialyzer or filter, a corresponding quantity of fluid has also been withdrawn via the membrane from the blood now flowing out of the dialyzer. The blood flowing out of the dialyzer or filter is thus thickened immediately after the reduction in rates Q S and Q M . A reduction in the quantity of the substitution fluid fed to the blood after the passage through the dialyzer (post-dilution) therefore leads directly to an increase in the density of the blood or the blood constituent in the blood circuit downstream of the dialyzer. When, on the other hand, rates Q S and Q M are reduced in the case of pre-dilution, the blood present in the dialyzer or filter has already been diluted by the previous inflow of substitution fluid. Since the filtration in the dialyzer corresponding to the substituate flow is reduced or does not take place, the density of the blood flowing back to the patient diminishes. It is therefore concluded that there is a supply of substitution fluid upstream of the dialyzer or filter (pre-dilution) if the density of the blood or the blood constituent, after the reduction in substitution rate Q S , has diminished by a preset amount or diminished by an amount which is greater than the preset threshold value.
On the basis of the increase or reduction in the density of the blood or blood constituent after the reduction in substitution rate Q S , it is therefore possible to conclude with a high degree of reliability that there is a post- or pre-dilution. The increase or decrease in the density should however exceed a preset threshold value, in order for it to be possible to distinguish reliably between a change in the density of the blood due to a change in the flow rates and general density fluctuations of the blood.
An increase in substitution rate Q S at which fluid is withdrawn from the blood is also possible instead of a reduction in substitution rate Q S . In this example embodiment, the density may be measured downstream of the point of the blood circuit at which substitution fluid is fed to the blood circuit in the case of pre-dilution and upstream of the first chamber of the dialyzer or filter. It is concluded that there is a supply of substitution fluid upstream of the dialyzer (pre-dilution) or filter if the density after the increase in the substitution rate has diminished by a preset amount, and it is concluded that there is a supply of substitution fluid downstream of the dialyzer or filter (post-dilution) if the density after the increase in the substitution rate has not diminished by a preset amount.
In this example embodiment, the density of the blood or the blood constituent in the blood circuit may alternatively also be measured downstream of the point of the blood circuit at which substitution fluid is fed to the blood circuit in the case of post-dilution. It can be concluded that there is a supply of substitution fluid upstream of the dialyzer or filter, preferably with a simultaneous increase in flow rate Q M , if the density after the increase in substitution rate Q S has increased by a preset amount, and it is concluded that there is a supply of substitution fluid downstream of the dialyzer or filter if the density after the reduction in substitution rate Q S has diminished by a preset amount.
As the density of the blood, it is possible to measure both the physical density or mass density, which describes a mass distribution, as well as the optical density of the blood, which is a measure of the attenuation of radiation (for example light) in a medium, i.e., the blood.
For the method according to the invention, consideration may be given in particular to all measurement methods with which a measurement of the physical or optical density of the blood or one of its constituents is possible. For the measurement of the change in the density, a first example embodiment provides for a measurement of the propagation speed of ultrasound in the blood along a measuring distance, while an alternative example embodiment provides for the measurement of the attenuation of light in the blood along a measuring distance. The measurement equipment required for this is generally known to the person skilled in the art. Moreover, optical detectors for the detection of blood and ultrasound measuring distances for the detection of air are in any case generally present in the known dialysis apparatuses.
In a further particularly preferred example embodiment, a signal signaling the operational state of pre-dilution is generated when a pre-dilution is detected, whereas a signal signaling the operational state of post-dilution is generated when a post-dilution is detected. The signal for the pre- or post-dilution may control further devices provided in the blood treatment apparatus. For example, an intervention in the blood treatment may be made.
The device according to the invention for monitoring the supply of substitution fluid may be a component of a blood treatment apparatus or form a separate unit. Since the components required for the monitoring device are generally in any case present in the known blood treatment apparatuses, an integration into the blood treatment apparatuses is appropriate. The corresponding sensors for the density measurement may for example be used. A microprocessor control is also available. The outlay on equipment is therefore small.
The monitoring device according to the present invention comprises a control unit for controlling the substitution apparatus and the ultrafiltration apparatus for withdrawing ultrafiltrate via the dialyzer membrane, in such a way that corresponding flow rates Q S and Q M may be adjusted for the measurement. A measuring unit is used to measure the density of the blood or the blood constituent and an evaluation unit is used to detect the pre- or post-dilution on the basis of the density measurement.
The method according to the present invention and the apparatus according to the present invention may give the user not only an indication of the type of treatment, i.e., pre- or post-dilution, but also deviations between the actual and the desired type of treatment. Moreover, automatic documentation or an automatic limitation of the input parameters is possible. With the method according to the present invention and the apparatus according to the present invention, it is also possible to control other operational parameters of the blood treatment apparatus depending on the respective operational state.
Not only the change in the corresponding flow rates, but also other parameters have an influence on the duration of the change in density. For example, the volume of the blood chamber of the dialyzer and the volume of the hose line sections following the blood chamber have an influence on the duration of the change in density. In this respect, the volume of a partial section of the extracorporeal blood circuit may also be deduced using the density measurement. The level of the change in density depends on the enclosed volume of blood.
Example embodiments of the method according to the invention and of the blood treatment apparatus according to the invention are described in greater detail below by reference to the figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an extracorporeal blood treatment apparatus with a device for monitoring the supply of substitution fluid, in particular for detecting pre- and post-dilution, in a very simplified schematic representation.
FIGS. 2A and 2B show the time-related course of the density in the case of pre-dilution and post-dilution with a reduction in substitution rate Q S and flow rate Q M , at which fluid is withdrawn from the blood via the membrane of the dialyzer or filter, by the same amount.
FIG. 3A and 3B show the time-related course of the density in the case of pre-dilution and post-dilution with an increase in substitution rate Q S and flow rate Q M , at which fluid is withdrawn from the blood via the membrane of the dialyzer or filter, by the same amount.
FIG. 4A and 4B show the time-related course of the density in the case of pre-dilution and post-dilution with an increase in the blood flow rate.
DETAILED DESCRIPTION
FIG. 1 shows, in a schematic representation, only the main components of a blood treatment apparatus that are relevant for the monitoring of the pre- or post-dilution. The present blood treatment apparatus is a hemo(dia)filtration apparatus, which comprises a dialyzer 1 , which is divided by a semi-permeable membrane 2 into a first chamber 3 , through which blood flows and which is referred to in the following as the blood chamber, and a second chamber 4 , through which dialyzing fluid flows and which is referred to in the following as the dialyzing fluid chamber. First chamber 3 is incorporated in an extracorporeal blood circuit 5 A, while second chamber 4 is incorporated in dialyzing fluid system 5 B of the hemo(dia)filtration apparatus.
Extracorporeal blood circuit 5 A comprises an arterial blood line 6 , which leads to inlet 3 a of blood chamber 3 , and a venous blood line 7 , which leads away from outlet 3 b of blood chamber 3 of dialyzer 1 . The patient's blood is conveyed through blood chamber 3 of dialyzer 1 by an arterial blood pump 8 , in particular a roller pump, which is disposed on arterial blood line 6 . The blood pump feeds blood to blood chamber 3 of the dialyzer at a specific blood flow rate Q b . Blood lines 6 , 7 and dialyzer 3 form a disposable intended for one-off use, which is inserted into the dialysis apparatus for the dialysis treatment. An air separator (drip chamber) may be incorporated into the arterial and venous blood line in order to eliminate air bubbles.
The fresh dialyzing fluid is made available in a dialyzing fluid source 9 . A dialyzing fluid supply line 10 leads from dialyzing fluid source 9 to an inlet 4 a of dialyzing fluid chamber 4 of dialyzer 1 . A dialyzing fluid discharge line 11 leads from outlet 4 b of dialyzing fluid chamber 4 to a drain 12 . A first dialyzing fluid pump 13 is incorporated in dialyzing fluid supply line 10 and a second dialyzing fluid pump 14 is incorporated in dialyzing fluid discharge line 11 . First dialyzing fluid pump 13 conveys dialyzing fluid from the dialyzing fluid source at a specific dialyzing fluid supply rate Q di to inlet 4 a of dialyzing fluid chamber 4 , while second dialyzing fluid pump 14 conveys dialyzing fluid at a specific dialyzing fluid flow rate Q do from outlet 4 b of dialyzing fluid chamber 4 to drain 12 .
During the dialysis treatment, dialyzing fluid may be fed from dialyzing fluid system 5 B as a substitution fluid to extracorporeal blood circuit 5 A via a substitution fluid line 15 , which branches off from dialyzing fluid supply line 10 upstream of first dialyzing fluid pump 13 .
Substitution fluid line 15 comprises two line sections 15 a and 15 b , one line section 15 a leading to arterial blood line 6 and the other line section 15 b leading to venous blood line 7 .
The substitution fluid is conveyed by means of a substituate pump 16 , in particular a roller pump, into which substitution fluid line 15 is inserted. A sterile filter 17 divided into two chambers 17 a , 17 b is incorporated into substitution fluid line 15 upstream of the substituate pump. The substituate pump together with the respective lines and the sterile filter form the substitution device of the dialysis apparatus. In order to pinch off the two line sections 15 a , 15 b of substitution fluid line 15 , shut-off elements, for example hose clamps, may be provided, which however are not represented for the sake of better clarity.
Blood pump 8 , first and second dialyzing fluid pumps 13 and 14 and substituate pump 16 are connected via control lines 8 ′, 13 ′, 14 ′, 16 ′ to a central control and computing unit 18 , from which the pumps are controlled taking account of the preset treatment parameters.
Blood pump 8 as well as first and second dialyzing fluid pumps 13 and 14 are operated in order to operate the hemo(dia)filtration apparatus as a hemodialysis apparatus, dialyzing fluid flowing through dialyzing fluid chamber 4 of dialyzer 1 . Substituate pump 16 is operated in order to operate the hemo(dia)filtration apparatus as a hemodiafiltration apparatus, so that sterile dialyzing fluid flows as a substitution fluid via sterile filter 17 optionally to arterial admission point 19 downstream of pump 8 and upstream of blood chamber 3 (pre-dilution) or to venous admission point 20 downstream of the blood chamber (post-dilution). Operation of the hemo(dia)filtration apparatus solely as a hemofiltration apparatus is however also possible, if first dialyzing fluid pump 13 is not operated and therefore the inflow of dialyzing fluid into the dialyzing fluid chamber of the dialyzer is interrupted.
The device for monitoring the supply of substitution fluid comprises a control unit which, in the present example of embodiment, is part of central control and computing unit 18 of the blood treatment apparatus. Moreover, the device for detecting pre- and post-dilution comprises a measuring unit 21 A for measuring the density of the blood or a blood constituent, which flows out of blood chamber 3 of dialyzer 2 via a venous blood line 7 back to the patient. Measuring unit 21 A measures the density of the blood in venous blood line 7 downstream of venous admission point 20 , at which substitution fluid flows into venous blood line 7 during the substitution.
Venous measuring unit 21 A comprises an ultrasound transmitter 21 A′ and an ultrasound receiver 21 A″, which are disposed along a measuring distance. The measuring distance may for example run through a venous drip chamber (not shown) or through a section of the venous blood line following the drip chamber. Such ultrasound measuring devices for measuring the density of media are known to the person skilled in the art. The measuring devices are based on the measurement of the propagation speed of ultrasound waves, which are transmitted by transmitter 21 A′ and received by receiver 21 A″. Alternatively, a measuring unit for measuring the attenuation of light may be used to measure the blood instead of an ultrasound measuring device, said measuring unit comprising, instead of the ultrasound transmitter and receiver, a light source disposed on one side of the measuring distance and a light sensor disposed on the other side of the measuring distance.
The device for detecting pre- or post-dilution further comprises an evaluation unit 22 , which is connected via a data line 23 to central control and computing unit 18 . Evaluation unit 22 receives the measured values of measuring unit 21 A via a further data line 24 .
The structure and the mode of functioning of the device for detecting a pre- and post-dilution are explained in detail below.
During the extracorporeal blood treatment, central control and computing unit 18 controls blood pump 8 in such a way that blood flows into blood chamber 3 of the dialyzer at blood flow rate Q b , and controls first and second dialyzing fluid pumps 13 , 14 in such a way that dialyzing fluid flows into dialyzing fluid chamber 4 at dialyzing fluid rate Q di and dialyzing fluid flows out of dialyzing fluid chamber 4 at dialyzing fluid rate Q do . Substituate pump 16 is controlled by control unit 18 in such a way that substitution fluid is fed to the blood optionally upstream and/or downstream of the blood chamber at substitution rate Q S .
For the monitoring of pre- or post-dilution, control unit 18 controls substituate pump 16 in such a way that its delivery rate is preferably reduced by a preset amount only for a preset time interval or substituate pump 16 is stopped. At the same time, control unit 18 controls first and second dialyzing fluid pumps 13 and 14 in such a way that flow rate Q M at which fluid is withdrawn from the blood via membrane 2 of the dialyzer or filter, whereby Q M =Q do −Q di , is simultaneously reduced within the same time interval by the same amount as the substitution rate has been reduced. The effect of this is that less fluid (ultrafiltrate) is removed from the blood via membrane 2 of dialyzer 1 . Before and after the changing of the delivery rates or stopping of the pumps involved, measuring unit 21 A measures the density of the blood or the blood constituent downstream of venous admission point 20 .
It is also possible for substitution rate Q S and flow rate Q M , at which fluid is withdrawn from the blood via the membrane of the dialyzer or filter, to be adjusted to a value of zero. This may be achieved, for example, by the fact that the dialyzer or filter is switched into a bypass operation, so that Q di is then also equal to zero. If there was previously a net ultrafiltration rate which has made a contribution to Q M , flow rates Q S and Q M in this case are not reduced by the same amount, since Q M was greater than the net ultrafiltration amount.
Evaluation unit 22 comprises a comparison device 22 A, which compares the value for the density of the blood or the blood constituent measured before the change in the delivery rates of the pumps with the value for the density measured immediately after the change in the delivery rates. The measurement of the density takes place within a specific time interval after the change in the flow rates, since the original values are re-established after the lapse of the time interval. The time interval should in any event be shorter than the length of the density change (rectangular function), empirical values being usable. It should be noted that the flow rate changes in the mentioned examples—Q S and Q M change by the same amount—lead only to a time-limited change in the density. On the basis of the change in the density, the evaluation unit then detects whether a dilution is taking place and ascertains whether a pre-dilution or post-dilution is present.
The operational states established by evaluation unit 22 are displayed on a display unit 25 , which is connected via a data line 26 to evaluation unit 22 . Furthermore, the evaluation unit generates two control signals, which on the one hand signal the operational state of pre-dilution and on the other hand the operational state of post-dilution. Both control signals are received by control unit 22 via data line 23 , which may undertake an intervention into the machine control depending on the respective operational state of pre- or post-dilution.
In the case of post-dilution, evaluation unit 22 ascertains a short-time increase in the density of the blood at the measurement point. This is due to the fact that the blood has thickened after the passage through blood chamber 3 of dialyzer 1 , since fluid (ultrafiltrate) has been withdrawn from the blood via membrane 2 of dialyzer 1 . Since the already thickened blood in post-dilution is no longer diluted sufficiently with substitution fluid, the density of the blood or the blood constituent increases downstream of the dialyzer for a specific time period. The delivery rates need to be changed only for a short time for the measurement, i.e., the original delivery rates may be re-established after the measurement has taken place, as a result of which an opposite—again time-limited—behaviour of the density change occurs.
In the case of pre-dilution, on the other hand, the blood flowing into blood chamber 3 is diluted by the inflow of substitution fluid upstream of the blood chamber. Immediately after the time at which the delivery rates of the pumps are reduced, still diluted blood first enters into the blood chamber, from which, however, sufficient fluid is no longer withdrawn via the dialyzer membrane after the reduction in the delivery rates. Consequently, the density of the blood emerging from the blood chamber and flowing back to the patient diminishes. The reduction in the density is again measured with measuring unit 21 A, evaluation unit 22 establishing the operational state of pre-dilution.
Comparison device 22 A of evaluation unit 22 calculates the difference between the two measured values of the density before and immediately after the change in the delivery rates. If the amount of the difference is greater than a preset threshold value, i.e., the values measured before and after the change in the substitution rate differ markedly from one another, evaluation unit 22 establishes that a dilution is taking place. Moreover, the evaluation unit ascertains whether an increase or decrease in the density is taking place, i.e., whether the difference between the measured values is positive or negative.
In the case of an increase in the density by an amount which is greater than a preset threshold value, the evaluation unit then ascertains the operational state of post-dilution. If the density has diminished by an amount whose magnitude is greater than a preset threshold value, the evaluation unit then ascertains the operational state of pre-dilution.
FIGS. 2A and 2B show the time-related course of the density of the blood in the case of pre-dilution ( FIG. 2A ) and post-dilution ( FIG. 2B ), substitution rate Q S on the one hand diminishing by a preset amount ΔQ S <0 and flow rate Q M at which fluid is withdrawn from the blood diminishing simultaneously by the same amount.
The graphs of FIGS. 2A and 2B denoted by A show the time-related course of the density in the case of pre- or post-dilution, when the change in density is measured by measuring unit 21 A downstream of venous admission point 20 , as is described by reference to FIG. 1 .
Alternative embodiments, however, also provide for a measurement of the change in density upstream of venous admission point 20 and downstream of blood chamber 3 or downstream of arterial admission point 19 and upstream of blood chamber 3 of dialyzer 1 . Two further alternative measuring units are provided for this purpose, which are denoted in FIG. 1 by 21 B and 21 C. Measuring unit 21 B measures the density upstream of venous admission point 20 and downstream of blood chamber 3 , while measuring unit 21 C measures the density downstream of arterial admission point 19 and upstream of blood chamber 3 .
The graphs of FIGS. 2A and 2B denoted by B show the time-related course of the density in the case of pre- ( FIG. 2A ) or post-dilution ( FIG. 2B ), when the change in density is measured with measuring unit 21 B, while graphs C show the time-related course of the change in density when the density is measured with measuring unit 21 C.
It is shown that a variation in substitution rate Q S , with a simultaneous change in Q M , also leads to a change in the density of the blood upstream of venous admission point 20 and downstream of blood chamber 3 . The density of the blood diminishes both in the case of pre- and post-dilution, the original value for the density being re-established in the case of pre-dilution, in contrast with post-dilution.
It may also be seen that a variation in substitution rate Q S also leads to a change in the density of the blood downstream of arterial admission point 19 and upstream of blood chamber 3 . The density of the blood increases in the case of pre-dilution, whereas with post-dilution it neither increases nor decreases, i.e. it remains the same.
Alternative embodiments of the invention provide for a measurement of the change in density with measuring units 21 B or 21 C, the evaluation unit concluding that there is a pre- or post-dilution on the basis of the nature of the change in density, which is shown in FIGS. 2A and 2B . Suitable devices with which the signals may be evaluated are known to the person skilled in the art. These devices may comprise comparators, timers etc.
It is also possible to combine the aforementioned measuring methods with one another, so that a pre- or post-dilution may be detected on the basis of two or three measurements at different measurement points. For example, it may be concluded that there is a pre- or post-dilution if a change in the signals characteristic of a pre- or post-dilution is detected at least in two measurements at different measurement points.
FIGS. 3A (pre-dilution) and 3 B (post-dilution) show the time-related course of the density of the blood or of a blood constituent, which is measured with measuring units 21 A, 21 B and 21 C, when on the one hand substituate rate Q S is increased by a preset amount and simultaneously the flow rate at which fluid is withdrawn from the blood via membrane 2 is increased by the same amount. The graphs are again denoted, similar to FIGS. 2A and 2B , by A, B and C.
It may be seen that an increase in substitution rate Q S , with a simultaneous change in Q M , leads to a change in the density at all three measurements points in the case of pre-dilution. In contrast to a reduction in the rate, the consequence of an increase in Q S and Q M downstream of venous admission point 20 in the case of a pre-dilution is not to a reduction, but rather to an increase in the density and leads in the case of a post-dilution not to an increase, but rather a reduction in the density (graph A). The density increases upstream of venous admission point 20 and downstream of blood chamber 3 both for the pre- as well as the post-dilution, the original value for the density being re-established (graph B) in the case of pre-dilution, in contrast with post-dilution. The density in the case of pre-dilution diminishes downstream of arterial admission point 19 and upstream of blood chamber 3 , whereas in the case of post-dilution it neither increases nor decreases, i.e. it remains the same (graph C).
In an alternative embodiment, control unit 18 and evaluation unit 22 are designed in such a way that substitution rate Q S and flow rate Q M are reduced and it is concluded that there is a pre- or post-dilution on the basis of the change in the density, as is described by reference to FIGS. 3A and 3B .
In a further example of embodiment, it is not substitution rate Q S or flow rate Q M , but rather blood flow rate Q b that is changed ( FIGS. 4A and 4B ). Control unit 18 controls blood pump 8 in this embodiment in such a way that blood flow rate Q b is increased by a preset amount ΔQ b . Graphs A, B, C again show the time-related course of the density of the blood or the blood constituent, which is measured with the three measuring units 21 A, 21 B, and 21 C. It may be seen that, with measuring units 21 A and 21 B, a pre- or post-dilution may be detected only with a more precise quantitative evaluation of the change in density. The evaluation unit therefore preferably evaluates the measured values of measuring unit 21 C, with which the density downstream of arterial admission point 19 and upstream of blood chamber 3 of the dialyzer is measured. Evaluation unit 22 ascertains a pre-dilution if the density has increased by a preset amount and it ascertains a post-dilution if the density has not increased by a preset amount, i.e. has remained the same. It is of course also conceivable for blood flow rate Q B to be reduced by a preset amount. The measurements then run in each case in the opposite direction. | An apparatus and a method for monitoring the supply of replacement fluid during an extracorporeal treatment of blood is disclosed. Detection of the supply of replacement fluid upstream or downstream of the dialyser or filter is based on a measurement of the optical or physical density of the blood or of a constituent of blood in the extracorporeal circulation. To detect pre- or post-dilution, the blood flow rate and/or the replacement rate and/or the flow rate of the fluid removed from the blood through the dialyser membrane is altered, and the density of the blood or of the constituent of blood is measured upstream and/or downstream of the dialyser. Additionally, an apparatus for treating blood with an apparatus for monitoring the supply of replacement fluid is disclosed. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a handheld, portable thermal-cauterizing forceps including an integrated thermal heating surface disposed at each tip.
There are many surgical cautery devices available for the surgeon to ablate and vaporize tissue. Hot knives and cutting coagulators have been used to make skin incisions. The cautery can also be used in surgery to aid in hemostasis or control bleeding by coagulating blood vessels. Employing various cautery modalities decreases the duration of some surgical procedures by providing the surgeon a rapid method of coagulation without the need for suture ligation of blood vessels encountered during dissection.
Typically, surgical cautery is accomplished by directing a heating process onto tissue. The heat may be generated by either a thermal or electro-surgical process. Most commonly, an electro-surgical process using a radio frequency (RF) is used. The RF units generate heat by using high frequency electrical current and the resistive nature of tissue to produce heat. This technique requires a bulky generator and heavy electrical components to operate. Typically, RF electrocautery units require a power lead cable to the electro-surgical hand instrument and a large surface area grounding pad. More often than not, radio frequency surgical units are bulky expensive units which require a cable connection. Employing RF cauterization in a surgical operation may add significant cost to the procedure because the grounding pad, cable and handpiece must all be either re-sterilized or replaced in the case of disposable use.
A less common method of generating heat for coagulation of tissue is by thermal cautery. Thermal cautery is achieved by electrical heating of a resistive-wire loop or resistive electronic part by applying an electrical voltage. The prior art describes many handheld disposable, hot-wire loop cautery instruments. These devices have severe limitations as to their scope of use in surgery. The heat generated by the handheld battery powered devices is very small with a low heat capacity. The available patented devices are effective for cauterization of only the smallest of blood vessels, such as, vessels in the sclera of the eye. These battery powered hot-wire cautery instruments are not effective for use in cauterization of larger blood vessels encountered in most surgical procedures. A technique employing the electrical over driving of a zener diodes to produce heat has also been described in several patents. This device is primarily for limited endoscopic applications.
SUMMARY OF THE INVENTION
In order to overcome the limitations and disadvantages of the prior art, the present invention provides, in an embodiment, a new and improved hand-held, high energy, portable thermal cautery forceps. More particularly, the new and improved surgical forceps instrument includes an enclosure which houses a battery and electronic control. Active ceramic heaters are provided on the two tips of the operative end of the forceps. In a second embodiment, the thermal forceps may alternatively be powered by an external power source.
The new thermo-cautery forceps device in accordance with an embodiment of the invention provides the surgeon with several significant improvements in the state of the art. A first benefit of the thermal-cautery forceps is that it is cordless and fully portable. In the first embodiment of the invention, no cables or external power supply is necessary. This keeps the operative field clear of wires and cables. The thermal cautery of this invention does not require any grounding pad or foot switches.
A second benefit is the very high heating capacity of the thermal elements of the device. Temperatures of over 1000° C. are easily obtainable. A preferred tip operating range is from 650° to 700° C. This heat capacity and temperature can easily cauterize medium and large blood vessels.
A third benefit provided by the new and improved thermal cautery forceps of the invention is its ability to heat to operating temperature in a very short time period, for example, within about one second. The preferred embodiment uses silicon nitride, ceramic heater elements. These new ceramic heaters exhibit rapid heating and cooling characteristics. Silicon nitride ceramic heaters have been used successfully in other fields outside surgery. To the inventor's knowledge, this is believed to be the first use within the field of surgical thermal coagulation.
In an alternative embodiment, less expensive alumina heaters and ceramic resistors or diodes may be employed in substitution for the silicon nitride ceramic heater elements to provide cost savings. However, such alternative types of heaters may be less preferred because longer times to obtain operating temperatures may be required.
In an embodiment, the preferred power source is a battery rendering the device completely portable. Four lithium metal 3 volt batteries can be utilized as well as dual 9 volt batteries, one for each tine. One preferred battery is TADIRAN® which provide 11.5 volts and are rechargeable. A 12 volt direct current power supply can be utilized as well with a connecting cord or cable.
A fourth advantage provided by the new and improved forceps is the placement of the thermal cautery heater elements at the ends of forceps tines. The unique position of the ceramic heater elements allows tissue and blood vessels to be easily grasped and directly coagulated in a controlled manner. The application of a closing or gripping pressure of the forceps against the tissue or vessel enhances the effectiveness of the coagulation.
A fifth benefit of the forceps device in accordance with the invention is to decrease the cost and enhance the availability of surgical cautery. The first embodiment of the thermal forceps allows for the device to be packaged as a sterile disposable instrument. The instrument can be used in emergency or field operations. The device may be used for hemostasis during outpatient surgical procedures in clinics and in surgery centers, as well as, at emergency scenes
Other objects and advantages provided by the present invention will become apparent from the following Detailed Description taken in conjunction with the Drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of the new and improved thermal cautery forceps instrument of the present invention in accordance with a first embodiment including an internal battery;
FIG. 2 is a top plan view of the new and improved thermal cautery forceps shown in FIG. 1;
FIG. 3 is an end elevational view of the new and improved thermal cautery forceps showing the front or forceps tines end;
FIG. 4 is an end elevational view of the new and improved thermal cautery forceps viewed from the rear or opposite end of the forceps;
FIG. 5 is an elevated cross-sectional view of the new and improved thermal cautery forceps shown in FIGS. 1-4, showing the logic controller board, LED indicator lamp, internal switch and internal battery;
FIG. 6 is a schematic block diagram of the electrical circuit for the new and improved thermal cautery forceps of the first embodiment of the invention comprising a battery powered portable device;
FIG. 7 is an elevated side view of the thermal cautery forceps instrument in accordance with a second embodiment of the invention including an external power supply unit;
FIG. 8 is a top plan view of the new and improved thermal cautery forceps shown in FIG. 7;
FIG. 9 is an elevated end view of the new and improved thermal cautery forceps of FIG. 7 taken from the forceps tine end;
FIG. 10 is an elevated end view of the new and improved thermal cautery forceps shown in FIG. 7, taken from the opposite end and showing the cable connector;
FIG. 11 is an elevated cross-sectional view of the new and improved thermal cautery forceps in accordance with the second embodiment, showing the housing and cable connection to the pair of heater units;
FIG. 12 is an elevated front view of the external power supply unit for use with the new and improved thermal cautery forceps in accordance with the second embodiment showing control features, including a power switch, audio speaker, temperature display, SET/READ switch, temperature control knob, recharging lamp and ready LED lamp;
FIG. 13 is a perspective view of a holster for carrying a portable thermal cautery forceps made in accordance with the present invention; and
FIG. 14 is a side elevational view of the holster shown in FIG. 13 .
From the above description it is apparent that the objects of the present invention have been achieved. While only certain embodiments have been set forth, alternative embodiments and various modifications will be apparent from the above description to those skilled in the art. These and other alternatives are considered equivalents and within the spirit and scope of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In accordance with a preferred embodiment of the invention, a new and improved thermocautery surgical forceps comprises a surgical forceps body including a pair of elongate tine members extending from the forceps body to respective free end tip portions spaced from the forceps body. The tine members are mounted to the forceps body in a manner providing resilient compressible movement of the tine members between a normally open position, wherein the tines are disposed in aligned, parallel, spaced-apart relationship, and a squeezed closed position, wherein the tip portions of the tine members are disposed in confronting abutting relationship. Each tine member includes a tissue contact surface 18 ′, 19 ′ defined on an inner facing surface of the tine member adjacent the tip portion. A ceramic heater element is disposed in each tine member so as to effectively heat the tissue contact surface to an elevated tissue cauterizing temperature. The ceramic heater elements are optionally connected to a power source. The tine members may be squeezed together to their squeezed closed position to grippingly, squeezably engage tissue to be cauterized between the tip portions. The tissue contact surfaces on the tines may be heated to a tissue cauterizing temperature to effectively thermocauterize the gripped tissue.
Referring now to FIGS. 1-6, a preferred embodiment of the new and improved thermocautery surgical forceps generally designated by reference numeral 10 is shown. Forceps 10 includes a forceps body or housing 12 for the battery 14 (see FIG. 5) and electrical control components 16 . Specialized ceramic heating elements 18 , 19 are disposed on the tips 20 , 21 of the forceps tines 22 , 24 . FIGS. 1-6 relate to the first embodiment of the invention, that of a portable unit 10 with an internal battery supply 14 . FIGS. 7-11 relate to the second embodiment of the invention, that of a cautery unit 26 configured as a thermal forceps 28 with an external power supply (not shown).
As shown in FIG. 1, the first embodiment of the cauterizing instrument 10 generally comprises a housing 12 and an integrated forceps tines assembly 32 . The housing 12 encloses the battery 14 (see FIG. 5 ), and a number of electrical control components 16 , such as controller electronics 34 , an LED 36 and an internal power switch 38 . The forceps tines 22 , 24 of the instrument, as shown in FIG. 1, exit from openings in the front end of the housing 12 . The forceps assembly comprises two tines 22 , 24 of equal length. Each tine 22 , 24 is constructed of a heater-carrier 40 , 41 and an insulator cover-piece 42 , 43 . The heater-carriers 40 , 41 comprise a metal arm 44 , 45 that supports an attached ceramic heater unit 46 , 47 . Each insulator cover-piece 42 , 43 is a shroud 48 , 49 that covers the heater 46 , 47 and its carrier arm 44 , 45 . Each shroud cover 48 , 49 is heat resistant and protects the surgeon's fingers from the heat generated by the ceramic heaters 46 , 47 . Each shroud 48 , 49 includes a recess 50 , 51 to fit the operators thumb and index finger to aid in holding the instrument. Inward compression on the shrouds 48 , 49 act to compress the heater carrier arms 44 , 45 and will cause the switch 38 (see FIG. 5) to close.
FIG. 2 shows a top view of the instruments with the LED 36 exiting the rear of the housing enclosure and the forceps shroud cover with finger recess The enclosure is rectangular in shape having a closed end and an open end The open end allows the forceps assembly to exit from the enclosure. The enclosure is composed of a plastic formed with an injection process. The open end of the enclosure is shown in FIG. 3 . The forceps are shown as well as the LED 36 on the top of the housing. The position of the LED 36 allows the surgeon easily visualize the operation of the instrument. The surgeon can see the LED 36 while it is held in the hand and operated. FIG. 4 shows the closed end of the housing.
Shown in FIG. 5 is a cross-sectional view of the enclosure containing a battery 14 for power supply. The battery may be rated form 3 volts to 24 VDC depending on the heating characteristics required. The battery 14 may be of an alkaline or lithium cell. In addition, two 9 volt batteries may be used, one for each tine 22 , 24 . Lithium metal batteries may also be utilized. One preferred battery is sold under the trademark TADIRAN®. The battery positive and negative terminals 54 , 56 are connected to the instrument circuitry by a terminal battery clip. Also, contained within the enclosure is a small circuit board 34 that is populated with an integrated circuit and support components. The circuit board 34 has connections to the power supply 14 , LED 36 , heater elements 118 , 19 and switch mechanism 38 . This circuit board 34 acts as a logic-controller to regulate the current delivered to the heating elements. The logic-controller circuit monitors the temperature and resistance of the heater elements 18 , 19 and regulates the voltage supply. At the onset of operation the logic circuit allows high current to flow to the heaters 18 , 19 aiding in initial rapid heating. The current is then reduced to maintain the heaters 18 , 19 at a set temperature. The controller circuit logic also controls the LED 36 to indicate the operative state of the heater elements 18 , 19 . The LED 36 will illuminate only if the battery power reserve or supply voltage attain a specified level and heaters reach the preset operational temperature. The logic controller also measures the internal resistance and temperature of the heater elements 18 , 19 . The LED 36 will fail to illuminate if these values fall outside the normal operational limits.
In an alternative design of the first embodiment a small piezo-electric speaker may be incorporated into the forceps enclosure. In the alternative design (not shown) the logic controller is further able to supply a piezo-electric speaker with supply voltage. The piezo-electric speaker provides the operator with auditory feedback pertaining to the operation of the instrument. The speaker emits a sound to give the surgeon an audio feedback as to the operation of the instrument. The sound indicates that the heating elements 18 , 19 are at the normal operative temperature for effective cauterization.
Also shown in FIG. 5, is the mounting arrangement of the forceps tines 22 , 24 . Each tine 22 , 24 is mounted on opposite sides of a rectangular neoprene spacer 52 . The pair of tines 22 , 24 and neoprene spacer 52 are fasted together by a binding pin 54 with end caps. The off-center arrangement fastening of the tines 22 , 24 to the neoprene spacer 52 allows for a spring like tweezer effect.
An electrical open/close single pole switch 38 is incorporated into the instrument. The switch 38 is positioned within the housing enclosure 12 between the base of the forceps tines 22 , 24 . The switch 38 is composed of two contacts 58 , 60 that are brought into contact when the forceps 10 are squeezed together. Closing the switch 38 allows current to be delivered to the heaters. The contacts 58 , 60 meet, as soon as, closure of the tines 22 , 24 is begun and stays in a closed position as long as the tines 22 , 24 are closed. Release of the forceps tines 22 , 24 will open the switch 38 and current supply to the heaters 46 , 47 will terminate.
The typical wiring diagram and schematic is shown in FIG. 6 . The schematic shows a DC battery 14 with positive and negative leads 54 , 56 connected to the logic control circuit board 34 . The circuit board 34 is able to regulate the current delivered to the heater elements 46 , 47 by measuring the internal electrical resistance of the heaters 46 , 47 and the voltage available from the battery 14 . The controller also will vary the initial resistance of the heater circuit to obtain quick heat up at power on. The controller logic also controls the illumination of the LED 36 . The LED 36 is illuminated when a preset temperature of the heaters 46 , 47 is reached. The ON/OFF switch 38 incorporated into the forceps 10 is also depicted. The switch 38 that is closed upon closure of the forceps 10 allows current to flow to the heaters 46 , 47 . Two heaters 46 , 47 are shown which are wired in parallel. The internal resistance of the two heaters 46 , 47 is about 5 to 10 ohms, preferably about 8 ohms, or 4 ohms per heater 46 , 47 . The typical heater 46 , 47 is composed of either alumina of silicon nitride or similar glass or ceramic material. This material specification is used due to high wattage density, rapid heat increase to 1000 degrees within one second, high level of insulation and non-stick nature of the ceramic to charred tissue. The preferred tip operating temperature range is 650 to 700° F. The second embodiment 26 of the invention is shown in FIGS. 7-12. In this embodiment an external power source is used to power and control a simple thermal cautery forceps. The forceps 26 in this embodiment is either of an inexpensive disposable or a more durable reusable design. FIGS. 7, 8 , 10 and 11 show the externally powered cautery forceps 28 . FIG. 7 is a side elevational view of the thermal cautery forceps 28 instrument of the second embodiment of the invention. A cable 72 connects the forceps to the external power supply unit (not shown). Each tine 74 , 76 is composed of a rigid metal carrier with ceramic heater 78 , 80 and an insulating plastic shroud 82 , 84 . FIG. 8 is a top plan view thereof; FIG. 9 is an end elevational view there of illustrating the forceps tine end. FIG. 10 is an end elevational view of the end opposite the forceps illustrating the cable connector 86 . FIG. 11 is a cross-sectional view of the second embodiment of the present invention, showing the housing 88 and cable connection. A pair of wires 90 , 92 connects the cable 72 to the pair of thermal heater elements 78 , 80 wired in parallel. Also shown in FIG. 11 is the neoprene spacer 94 . The spacer 94 is positioned between the forceps tines 74 , 76 . An off center-binding pin 96 extends through the tines 74 , 76 and the spacer 94 provides a spring effect. The spring effect also activates the ON/OFF switch 98 . The switch 98 is composed of two electrical metal contacts 100 , 102 affixed to the inside of each forceps tine 74 , 76 .
FIG. 12 is a front elevation of the external power supply unit 103 . This unit 103 contains a power switch 104 , audio speaker 106 , digital temperature display 108 , SET/READ switch 110 , temperature control knob 112 , recharging indicator lamp 114 and ready LED lamp 116 . The power supply unit 103 may be a 12 volt DC unit.
As shown in FIG. 12, the cable 72 connected to the forceps 26 enters the power unit 103 . The power switch 104 is located on the front panel 118 that illuminates when switch 104 is on. The speaker 106 signals the surgeon of proper heater element temperature for cauterization. The speaker 106 will sound when the instrument reaches the SET temperature after the forceps are squeezed together to initiate heating. The output of the speaker 106 is vented outside the power unit through a small port shown in FIG. 12 . The unit also contains a temperature control. The temperature may be varied by positioning the SET/READ switch 110 to the SET position and rotating the temperature adjust knob 112 to the desired temperature. The digital temperature display 108 reports the desired set temperature in degrees fahrenheit. The temperature adjust control 112 may either be of an analogue or digital type. This control allows the surgeon to select a temperature for a desired effect depending on the thickness and moisture content of the tissue to be cauterized. The digital temperature display 108 may indicate the actual temperature of the ceramic heater elements 78 , 80 when the SET/READ switch 110 is positioned in the READ position. The LED indicator 114 is incorporated into the power supply, which is illuminated when the batteries are recharging. The Heater On Indicator 116 is incorparated into the power supply, which is illuminated when the heater elements are heated. This occurs whenever the power unit is connected to a 110 VAC line. A charging circuit (not shown) regulates the recharging process.
FIGS. 13 and 14 illustrate a holster 130 for accommodating the forceps 10 or 26 . A cavity 132 receives the tine end of the forceps 10 or 26 . A loop 134 or slits 136 , 138 may be provided for attaching the holster 130 to a belt 140 .
The foregoing discussion of the invention has been presented for purposes of illustration and description. Further, the description is not intended to limit the invention to the form disclosed herein. Consequently, variations and modification commensurate with the above teachings, and the skill or knowledge in the relevant art, are within the scope of the present invention. The embodiments described herein above are further intended to explain 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 various modification required by their particular applications or uses of the invention. It is intended that the appended claim be construed to include alternative embodiments to the extent permitted by the prior art. | A portable, thermal cauterizing forceps device for use in surgery. The device incorporates a pair of ceramic heater elements mounted within the tips of the tines of a forceps. The forceps is used to grasp tissue or blood vessels and apply heat to effect cauterization. In the case of the first embodiment of the invention, the forceps instrument incorporates a battery and control electronics. The thermal-forceps is of a self-contained wireless, handheld disposable design. In a second embodiment of the invention, the forceps handpiece is connected to an external power source. Both embodiments of the forceps incorporate set of rapidly heating ceramic heater elements that may be composed of silicon nitride. An LED provides the operator feedback as to the operating level of the heaters and/or battery reserve. Enhancements to the second embodiment include a rechargeable power supply, variable control of the heater temperature, as well as a, digital display of the tip temperature. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a roll support assembly for supporting webs wound in separate supply rolls and the ends of which are to be joined to produce a continuous web.
Such roll support assemblies are used for example in connection with so-called tube-making machines in a plant for producing paper sacks. They are to render possible an uninterrupted supply of paper webs to the tube-making machine and they serve for setting into motion a replacement roll while another expiring roll still delivers roll material. As a rule, the unwound web is drawn off by draft rollers and draft rolls in the tube-making machine. The forward end of the roll material running off the replacement roll can be attached to the expiring material of the nearly unwound roll in such a roll support assembly during operation. In the case of paper webs, the joining is effected preferably by adhesives. After the joining of the material of various rolls, the still projecting trailing end of the nearly unwound roll can be severed by means of cutter blades and corresponding rollers so that roll material leaves the roll support assembly without interruption and is of uniform thickness except for the area of attachment from roll to roll.
In particular in the paper manipulating industry, such as for example in the manufacture of paper sacks, the supply rolls have a very great weight and present particular problems not only for that reason but also because of the sensitivity of paper webs in particular in respect of re-positioning a roll from a main support to an auxiliary support. Such re-positioning of the expiring roll from a main support to an auxiliary support is to free the main support for receiving a fresh supply roll and is necessary in particular for the production of endless webs.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a roll support assembly for supporting webs wound in separate supply rolls and the ends of which are to be joined to produce a continuous web, comprising a main support for supporting each newly loaded supply roll and an auxiliary support to which each supply roll may be transferred when partly expired to enable a further supply roll to be loaded on the main support, wherein in the main support, the supply roll is supported at its axial ends and in the auxiliary support the supply roll is supported by means of at least one group of rollers operative to engage the peripheral surface of the supply roll and mounted in such a manner as to be movable by mutually equal amounts towards and away from the axis of the supply roll, the main and auxiliary supports being movable relative to one another such that a partly expired roll may be simultaneously supported by both supports.
A roll may be supported in practice in one of two possible ways, namely it can be supported at its axial ends or by rollers engaging its periphery. The invention relies on a change from one form of support to the other when transferring a supply roll from the main support to the auxiliary support. The auxiliary support engages the periphery since in operation the auxiliary support receives a partly unwound roll which is therefore lighter.
Some of the preferred features of the invention fulfill the condition that the geometrical roll axis of the auxiliary support is fixed independently of the spacing of any of the rollers from its axis. It is advantageous to group together four or another even number of support rollers in an axially symmetrical group but alternatively three or any odd number of support rollers may be grouped together provided that they fulfill the condition of being commonly movable with equal spacing from the imaginary rolling axis for a supported supply roll.
The position of the rolling axis fixed by equidistance from the support rollers of the auxiliary support relative to the axis of a supply roll in the main support is thus determined merely by the entire position of the auxiliary support relative to the main support. The auxiliary support can be used, on a suitable displacement track and slides, or carriages, for displacing the auxiliary support relative to the main support, for engagement with the same roll which is held also by the main support, the roll axes of the two supports coinciding coaxially. Under the circumstances, no positional displacement of any kind occurs at the expiring roll, it being immaterial whether its weight then rests on the main support or on the auxiliary support, provided the support rollers of the auxiliary support lie on the periphery of the roll.
For accelerating the rotation of a new supply roll, a drive mechanism may be provided on the main support and may preferably comprise a driving roller which is designed to engage an end face of the roll. Such a driving roller may be connected by means of a belt or chain drive or by means of a transmission shaft to a drive motor which is also in connection with draft rollers or draft rolls for drawing the roll material off the roll in such a manner that the peripheral speed of the driving roller agrees approximately with the drafting speed of the expiring roll material, or is at least synchronized therewith. Preferably the driving roller will be mounted by way of a shaft on a pneumatic pivoting and pressing mechanism which in turn is attached to one of the support arms or members of the main support. Upon insertion of a replacement roll into the main support, the driving roller can thus be pivoted and pneumatically, i.e. resiliently yieldingly pressed against one of the end faces of the roll.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a diagrammatic side view of a roll support assembly according to the invention with a main support which supports a replacement roll, and with an auxiliary support on which a nearly expired roll is located,
FIG. 2 is a diagrammatically shown section of the auxiliary support according to FIG. 1 in a different operational position,
FIG. 3 is a diagrammatically shown section of the main support according to FIG. 1, on which additionally a driving mechanism for accelerating rotation of a replacement roll is disposed,
FIG. 4 is a diagrammatically shown view of the rear of a support beam with mandrel of the main support according to FIG. 1, and
FIG. 5 is a diagrammatically shown side view of the roll supporting according to FIG. 1, during transfer of a partly expired roll from the main support to the auxiliary support.
Similar component parts of the constructional example are denoted in all figures by the same reference numerals.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The roll support assembly according to FIG. 1 comprises a main support 1 and an auxiliary support 2. An at least approximately complete replacement roll 3 is disposed on the main support and a nearly expired roll 4 on the auxiliary support. The transfer of the roll 4 from the main support to the auxiliary support had been accomplished in a preceding operational step. During this operational step the roll had the magnitude indicated by a dash-dotted line 5. In FIGS. 2 and 5 which show the transfer, a roll of this magnitude is designated 5 and will be referred to as an interchange roll.
Let it be assumed that in the given example the rolls are paper rolls. A paper web 6 off the replacement roll 3 and a paper web 7 off the roll 4 are drawn over a common guide roller 8 out of the roll support assembly in the direction of arrow 9. In the region of the roll support assembly marked by the capital letter A there may be located gumming mechanisms or other adhesion effecting mechanisms, presser rollers extending parallel to the roll axis of the auxiliary support and cutter devices of constructional form known per se, which effect adhesion of the two paper webs 6 and 7 one to the other along a transverse line and permit the trailing end of the paper web 7 to be cut off.
The main support 1 comprises a support arm 12 on each of the two end faces of the roll 3. One each of the support arms there is located a mandrel 13 which, as shown in FIG. 4, engages in a sleeve 14 on which the roll 3 is wound. The sleeve, the mandrels at the two ends of the sleeve and the whole roll are able to form a substitute for a separate support shaft. However, in the case of insufficient carrying capacity it may be advantageous to guide a support shaft instead of the mandrels through the whole sleeve.
As shown in FIGS. 1 and 4, each support arm 12 is fixed to a carriage 15 which rolls on a rail track 16 extending approximately parallel to the axis of the roll 3. Thus the support arms can be guided on this rail track to the two end faces of the replacement roll to such extent that the mandrels are securely located in the ends of the sleeve 14. If the replacement roll was previously suspended from a hoist, it may be released therefrom as soon as the support arms are fixed in the last mentioned position. As soon as the roll has attained in the course of operation the size of an interchange roll 5, it can be received by the auxiliary support 2. For the transfer the roll can be released simply by moving the support arms 12 apart on the rail track 16 until the mandrels 13 have left the ends of the sleeve 14. If, in place of the mandrels 13, a support axis extending completely through the sleeve 14 was present, the interchange of the rolls would require much more time, work and expenditure for the apparatus.
As seen in FIGS. 1 and 5, a base frame 17 connects the main support 1 to the auxiliary support 2. Carriage wheels 19 of the auxiliary support engage in approximately rectilinear tracks 18 in such a manner that the auxiliary support can be displaced relative to the main support 1 relatively easily on the base frame. For the displacement there is provided a traction device 20 of a construction known per se with an endless cable or chain loop passing over pulleys or sprockets and connected by a driver member to the auxiliary support.
The auxiliary support 2 comprises at least one group of four support rollers 25 which are designed to lie against the surface of the roll 4 or 5 with roller axes which are parallel to each other and to the axis of the roll. Each of the support rollers 25 is rotatably mounted on a free end of a support beam 26 the center region of which is pivotally engaged by a control arm 27. The ends of the support beams 26 remote from the rollers are pivotably secured to a support frame 29 and are pivotable about a common axis defined by a bearing 28. These two support beams 26 are pivotally connected to a common control slider 30 by means of the control arms engaging their center regions. A hydraulic or pneumatic drive motor 31 engages each control slider. Each control slider is also mounted on the support frame in a rectilinearly movable manner.
The two support rollers 25, support beams 26, control arms 27 and common control slider 30 together with the support frame 29 and the bearing 28 form a scissors-like support for a roll. In fact such a scissors-like support with only two rollers would be sufficient for receiving an interchange roll 5. The mutually coupled parts of the support form a control drive which ensures equidistance of the two support rollers from an imaginary geometrical roll axis within the auxiliary support 2. However, upon transfer of an interchange roll 5 to a single scissors-like support the drive motor 31 connected thereto must be matched very carefully to the diameter and the weight of the roll, if the interchange roll is to lie co-axially to the imaginary geometrical roll axis and must not be lowered or lifted during transfer. However, the stated problem of matching the drive motor is not present when two mutually opposing scissors-like supports are disposed on the support frame and the drive motors connected thereto operate similarly. The auxiliary support described as an example comprises two mutually oppositely disposed scissors-like supports each with two rollers, of which one of the supports engages the top of the roll and the other the bottom.
According to FIG. 2 the two scissors bearings are connected together by means of a mechanical coupling drive. This coupling drive comprises a connecting rod 32 which couples together the free ends of two lever arms 33 and 34 in a pivotal manner. The lower lever arm 33 is in rigid connection with the support beam 26 of the lower left-hand support roller 25. The upper lever arm 34 is attached to the support arm of the upper right-hand support roller 25. A similar coupling drive, including a lower lever arm in rigid connection with the support beam of the lower right-hand support roller 25 and an upper lever arm in rigid connection with the support arm of the upper left-hand support roller 25, is provided. With such a mechanical coupling a common control drive for all four support rollers is produced the equidistance of which from an imaginary geometrical roll axis is ensured. This roll axis is fixed in relation to the support frame 29 and coincides co-axially with the axis of a roll 4 or 5 independently of the diameter thereof, as soon as the four support rollers rest on the roll surface. A similarly acting coupling of the two scissors-like supports may be obtained by hydraulic or pneumatic coupling members by way of the two pusher motors 31. Also the use of equivalent electrical coupling members is possible in the given context and, similarly to that of hydraulic or pneumatic coupling members, is advantageous in particular when only one single carrying scissors bearing is to be coupled to an oppositely disposed support roller and the position of the scissors-like support is to be controlled dependently on the position of the oppositely disposed roller.In this last mentioned case the auxiliary support comprises a group of three rollers the equidistance of which from an imaginary geometrical roll axis is ensured, in spite of the variability of the spacing, by the coupling of the roller supports.
The auxiliary support 2 may comprise a plurality of equal groups of support rollers 25 which are then disposed one adjacent the other along a roll. The number of groups is a function of the length of the support rollers, the length of the rolls and the carrying capacity of the support beams.
In the constructional example described and illustrated the geometric roll axis of the main support 1 determined by the mandrels 13 and the geometrical roll axis of the auxiliary support 2 determined by the entire control drive of the two scissors bearings have the same spacing from the base frame 17 and from the tracks 18, respectively. These tracks extend in such a manner that in one position of the auxiliary support on its path the geometrical roll axis thereof coincides co-axially with that of the main support. This position is also fixed as the forward end position of the auxiliary support.
As soon as the roll 4 has completely expired, the support beams 26 with the support rollers 25 located thereon are pivoted into a position which is illustrated in FIG. 2. In this operational state the auxiliary support 2 can be moved on the base frame 17 by means of the tracks 18 to an interchange roll 5 which is still located between the mandrels 13 of the main support 1. FIG. 2 illustrates in dash-dotted lines and in full lines two positions of the interchange roll 5 which engages in an open inlet of the support frame 29. Upon coincidence of the geometrical roll axes of the main support and the auxiliary support according to the illustration in FIG. 5, the drive motors 31 press the control sliders 30 in the direction of the interchange roll in such a manner that the support rollers 25 lie on the surface of the interchange roll and support the latter. The interchange roll 5, according to FIG. 5, had previously the magnitude of a replacement roll 3 drawn in broken lines. As soon as the mandrels 13 have been moved out of the interchange roll in the manner previously described in connection with FIGS. 1 and 4, the auxiliary support 2 can be guided back from the forward end position according to FIG. 5 into the rearward end position according to FIG. 1 again by means of the traction device 20 and a complete replacement roll can be inserted into the main support. As may be seen from a comparison of FIGS. 1 and 5, the change of the roll from the main support on to the auxiliary support can be effected without interruption of the operation, since the paper web 7 is guided and diverted by the lower left-hand support roller 25 and can run off without disturbance.
According to FIG. 3, a drive mechanism for accelerating rotation of a replacement roll 3 may be arranged at least at one of the support arms 12 of the main support 1. In this case the support arm 12 is provided with an extension 36 to which a shaft bearing 37 is attached. In this shaft bearing is located a rotatable shaft 38 which supports at one end of it ends a drive roller 39 and at its other end a belt pulley 40. A driving belt 41 connects the belt pulley under certain circumstances by way of a further gearing to a drive motor (not illustrated). Preferably that motor is employed as a driving motor for the mechanism according to FIG. 3, which also serves for drawing off the paper webs 6 and 7 by means of a drafting shaft (longitudinal shaft) in the region of the tube-making machine or under certain circumstances the roll support.
The shaft 38 lies in a radial plane with reference to the axis of the main support 1. Though a perfectly radial mounting of the shaft during the operation is advantageous, it is not essential. In any case, however, the drive roller must lie as resiliently as possible on the end face of the replacement roll 3 in such a manner that the drive roller is able to drive the roll for rotational movement about the roll axis. Pivoting and pressing means (not illustrated) preferably of pneumatic kind at the drive mechanism, according to FIG. 3, may ensure that the driver roller lies resiliently on the replacement roll and permits it to be swung out of the region of the roll, as soon as the latter does not require any more the particular drive or is to be transferred to the auxiliary support.
A brake device (not shown) may be provided engaging the roll in the auxiliary support 2 to maintain roll tension.
The illustrated and described embodiment of the roll support assembly according to the invention has the advantage over many other possible embodiments since it is constructed in a particularly simple manner. | A roll support assembly for supporting separate supply rolls carrying webs which are to be joined to one another to provide a continuous web supply. The support assembly includes a main support onto which each new supply roll is loaded and in which the roll is supported at its axial ends. The assembly includes an auxiliary support to which a partly expired roll may be transferred to enable a further supply roll to be loaded on to the main support. The auxiliary support incorporates rollers engaging the peripheral surface of the partly expired roll and is mounted movably with respect to the main support such that a partly expired roll may be simultaneously supported by both the main and the auxiliary support. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to high temperature heat exchangers and particularly, although not necessarily exclusively, heat exchangers in which a fluidised bed provides one of the materials in heat exchange relation.
For gas-to-gas heat exchange at temperatures too high for metal constructions, it is known to use ceramic heat exchangers, because they are capable of operating at higher temperatures than are obtainable from metal constructions. The use of ceramic materials poses a number of difficulties however.
For example, ceramic constructions are bulky as compared with metal constructions. This is firstly due to the relatively poor thermal conductivity of ceramics as compared with metals, and also because they cannot match the high heat transfer coefficients of a metal construction, particularly when the fluid to be heated is a liquid or gas under pressure. The total tube surface area in a ceramic heat exchanger must be of the order of four times its metal equivalent for the same heat transfer rate.
The bulk of a ceramic construction is increased further because of the more complex sealing arrangements required for the tube ends in order to limit thermal expansion stresses on the ceramic tubes. The minimum spacing between tubes is limited because of this requirement and even using a compact arrangement as described in U.S. patent application Ser. No. 6/9769 the tubes cannot be pitched closer than 1.8 tube diameters.
Although there may be many instances where the user is not concerned by the bulk of the apparatus, this adds to the cost and itself imposes design difficulties. For a given heat exchange rate, the total volume could be increased by increasing the length and numbers of the tubes, but increasing length accentuates the problems of material weakness as already mentioned, and it is undesirable to employ a plan form that is markedly oblong if heat losses are to be minimised.
Further problems arise from the brittle nature of ceramic materials, and especially their weakness in tension as compared with metals. In a tubed heat exchanger, where it is desirable to employ thin-walled tubes for efficiency of heat transfer, particularly having regard to the poor thermal conductivity of ceramics as compared with metals, these inherent weaknesses of ceramic materials can be a serious limitation.
The weakness of ceramic materials is also a significant factor in the problems that arise when trying to make seals between ceramic tubes and the end walls of a heat exchange chamber because of the need to allow for relative thermal expansion in high-temperature operation without overstressing the material. These difficulties are accentuated if the seals have to be capable of withstanding relatively high pressure differentials. Because of the fragility of ceramic materials and their high operating temperatures, seals suitable for metal heat exchanger tubes cannot be adapted to ceramic tubes.
Metal-tubed heat exchangers are also already known for fluidised bed heating apparatus. Such apparatus has gained acceptance in application to compact boilers and shallow bed water heaters, because of its advantages in being able to provide high heat transfer rates and uniform heating. In known systems, heat is extracted from the fluidised bed by passing the fluid to be heated, e.g. water or steam, through metal tubes which are submerged in the bed. There would be distinct advantages from the application of ceramic constructions to fluidised bed systems. For example, if heating clean air to high temperatures it is possible to show by theoretical calculations that a fluidised bed at 900° C. could give heat transfer rates equivalent to a heat input in the form of a hot gas stream at 1600° C.
However, ceramic material constructions have not been adopted for fluidised bed heating apparatus for practical reasons, and in particular because all the problems indicated above that come with the use of such materials would be encountered in a particularly severe form. For example the ceramic tubes submerged in the bed would be subjected to random forces greater than those typically experienced in a gas-to-gas heat exchanger and such forces can generate considerable local pressures that may crack a brittle ceramic material.
The increased bulk of ceramic constructions is also a disadvantage which is particularly apparent in the fluidised bed apparatus where it is possible to achieve a very high intensity of heating that allows compact metal constructions to be produced. Even if this disadvantage is accepted and the output rating of a fluidised bed apparatus using ceramic tubes is increased by accommodating more tubes in a deeper bed, that requires an increase of the fluidising gas pressure, which produces other problems.
The present invention has a special application to such fluidised bed heat exchange apparatus, although it can be usefully applied to other high temperature applications, such as for gas-to-gas exchangers.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided heat exchange apparatus having a chamber with two opposite and mutually transverse pairs of side walls each comprising a series of parallel ceramic blocks superimposed on each other and formed with recesses that provide seatings between adjacent blocks for ceramic tubes extending through the chamber, and sealing means in said seatings for the ends of the tubes, said tubes being arranged in a series of banks at different levels and successive banks extending transversely to each other whereby the seatings at said successive levels are provided in alternate pairs of said side walls of the chamber.
In this arrangement, which is not necessarily limited to use for fluidised bed applications, the banks of tubes can be pitched so that the tubes of successive banks are almost touching, if this is required, and the total tube surface area can be correspondingly greatly increased for a given chamber volume.
By using mutually transversely extending series of tubes in this manner, it is possible to provide external tube supports so arranged that the transverse forces on one tube can be at least partly transferred to another adjacent tube as an axial force thereon, which the ceramic material is better able to resist.
In fludised bed applications, the banks of tubes will be normally disposed at horizontal or near horizontal levels, but in other heat exchange apparatus the tubes may be oriented in other directions. The references to the different levels are therefore relative and are not intended to imply that the banks are necessarily spaced in the absolute vertical direction.
According to another aspect of the present invention, in order to mitigate the relative fragility of ceramic materials, there is provided a tubed heat exchange apparatus comprising a chamber that has a series of ceramic tubes extending therethrough for a fluid flow in heat exchange with the chamber interior, wherein said tubes are provided with internal support means intermediate their length reinforcing them against bending stresses.
By these means it is possible to employ tubes with thinner walls and/or in greater lengths, so that increases are possible both in the efficiency of operation and in the maximum size of heat exchanger that can be constructed. Said internal support means can take the form of elongate load-carrying elements provided with spacer members that engage the internal walls of the tubes in order to transfer loads from the tubes to the load-carrying elements. Additionally there may be elements supporting the tubes externally as aforementioned.
More especially in a fluidised bed heating apparatus it is important to take precautions against rupture of any of the ceramic tubes, because if that occurs the material of the bed may seriously contaminate the hot gas flow through the tubes with solid particles from the combustion process. This danger must therefore be countered before it can be practical to use ceramic constructions for producing a hot clean gas flow by fluidised bed operation. But as already mentioned, it is not possible to make the tubes stronger by increasing their wall thickness because that would impair the efficiency of heat transfer.
In a preferred construction, therefore, the supporting means comprise one or more restrictions in the internal cross-section of the tubes, such that the flow of the fluid through a tube is retarded after passing through a restriction therein.
By this means, if ash or dust particles are entrained in the gas stream through a tube, because of cracking of the tube for example, the particles will tend to settle out as the speed of the gas stream drops after passing through a restriction. As they gradually accumulate they increasingly block flow through that tube while the total gas flow is largely unaffected because it is carried by the remaining undamaged tubes. The restrictions may take the form of one or more orifices in the tube interior, but additionally or alternatively, one or more mesh or porous members may be disposed inside the tube for flow restriction.
As already indicated the cumbersome nature of satisfactory ceramic tube seals added to the problem of sealing at high pressures is another reason for the limitations in performance of a ceramic heat exchanger compared with a metal construction, and it will be understood from preceding comments that this can be particularly relevant to fluidised bed apparatus.
According to another aspect of the present invention, there is provided heat exchange apparatus comprising a ceramic-walled chamber traversed by ceramic tubes for a fluid flow in heat exchange with a material in the chamber, the tubes extending between apertures in opposite side walls of the chamber and having ceramic fibre sealing means in said apertures, said sealing means comprising resilient end seals held compressed between outer abutments and the tube ends but permitting relative thermal expansion between said abutments and the tubes.
The invention will be described by way of example with reference to the accompanying schematic drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an axial section of an end portion of one tube of a ceramic heat exchange apparatus according to the invention,
FIG. 2 is an end view of an end spacer element in the construction shown in FIG. 1,
FIG. 3 is an axial section of a heat exchange apparatus according to the invention that incorporates the features shown in FIGS. 1 and 2,
FIG. 4 is an exploded perspective view of a further heat exchange apparatus according to the invention,
FIG. 5 is a detail view of tube support means in the heat exchange apparatus of FIG. 4,
FIGS. 6 and 7 are further illustrations of the two alternative forms of support means in FIG. 5,
FIGS. 8 to 11 are detail sectional views showing alternative end seal arrangements for the ceramic tubes of the heat exchangers of the preceding figures, and
FIG. 12 is an exploded view of a part of FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring initially to FIGS. 1 to 3 of the drawings, the ceramic heat exchange apparatus comprises a casing 2 the walls of which are composed of ceramic blocks 2a and define an internal chamber 4 through which run ceramic tubes 6 for a flow of fluid, e.g. air, to be heated by the heat of combustion in a fluidised bed in the chamber, the bed level being indicated at X. The casing walls are generally constructed in the manner indicated in our U.S. patent application Ser. No. 9769 filed Feb. 6, 1979 (the contents of which are incorporated herein by reference), and in particular the ends of the tubes are received in recesses 8 between individual wall blocks 2a that form a pair of opposed chamber side walls between which the tubes extend, sealing between the tubes and these recesses being obtained by precompressed ceramic fibre seals 10.
A rod 12 extends through each tube and is located centrally in its tube by spacer discs 14 fixed at intervals along its length. Fixed to the ends of the rod are slightly larger discs 14a in the casing wall recesses 8 beyond the ends of the tube. The end discs 14a bear against auxiliary precompressed ceramic fibre seals 22 between the discs and the tube ends and locate the rod axially. The discs 14a are held against the seals 22 to apply a precompression force by axial engagement means such as apertured end plate 26 of a header 24 (FIG. 3) clamped against the casing wall with a ceramic fibre gasket 30 interposed.
All the discs have holes 16 in them that allow fluid to pass through the tubes but that form restrictions so that the flow speeds up as it goes through the holes and then slows downs as the flow passage increases again after each disc. For assembly, all the spacer discs except one end disc 14a are firmly attached to the rod before it is inserted in its tube. The final disc may then be added, positioning of the disc putting the auxiliary ceramic end seals 22 under some degree of compression. If necessary a securing element 28 such as a nut screwthreaded onto the end of the rod, or a circlip can prevent the rod slipping out of this end disc.
The arrangement allows for differential thermal expansion between a rod and its tube, which is likely to occur because the rods will be of a relatively high strength material, such as a heat resistant metal alloy, having a different thermal expansion rate and could otherwise either apply an undesirably large compression load to the ceramic tube at one temperature level or be able to shift axially at another temperature level.
If the ceramic tube should crack while in use the rod spacer discs act as locating supports to hold the tube in position so as to limit the strains, for example from buffeting forces, that might otherwise rapidly lead to complete destruction of the tube. In this state, however, it is possible for particles of the fluidised bed material to seep into the tube if the bed pressure is higher than the gas pressure in the tubes. The abrupt velocity changes brought about by the apertured spacer discs will then tend to cause these solid particles to be deposited in the regions immediately downstream of the spacer discs, where the velocity drops. As the solid matter builds up in these regions the damaged tube is gradually blocked while flow continues through the undamaged tubes because of the lower overall pressure drop in these, so that at least a significant part of the foreign matter entering the tube is prevented from being carried away in the heated gas flow.
Instead of apertured discs, the spacer elements may be formed by a mesh or by a porous mass which can similarly act as a suitable restriction of the tube cross-section, provided these or other elements give the required degree of support between the tube and the reinforcing rod 12.
In FIG. 4 a further ceramic heat exchange apparatus for a fluidised bed is illustrated. As in the preceding embodiment, the chamber 40 is of rectangular plan form and has side walls 42 that comprise a series of ceramic blocks 44 laid one above the other and with recesses in their upper and lower edges that are in registration to form cylindrical openings that provide seatings 46 for seal arrangements 48 for the ceramic tubes 6 that extend through the chamber within the casing.
In this case, tube sealing arrangements are provided in all four side walls for the tubes which are arranged at successive levels in banks 50a, 50b at right angles to each other so that for each side wall the ceramic blocks 44 have heights equal to twice the vertical pitch of the centers of the banks of tubes. The arrangement of the tubes in mutually transverse banks makes it possible to pitch the successive banks very closely to each other without the wall blocks being unduly weakened by the formation of the recesses, even though the recesses 46 seating the tube end seals have a diameter greater than the tubes themselves. Thus, if the tube seatings 46 in each side wall are spaced at a vertical pitch of 2.5 times the tube diameter, then the effective vertical pitch of the successive banks of tubes is 1.25 times the tube diameter: this is considerably lower than 1.8 times the tube diameter that is the minimum that can be achieved with the most compact designs already known.
In each side wall the tube seatings are shown in vertical alignment at successive levels, i.e. on a rectangular matrix, but alternative rows of seatings can be staggered, i.e. giving a diamond matrix, if preferred.
FIG. 4 shows a number of constructional details applicable to but not illustrated in the earlier figures. For example, this figure illustrates how the ceramic wall blocks of the casing are mounted in an outer metal main frame 52 comprising a bottom casing part 54 provided with inlet conduits 56 leading to injection nozzles 58 for the combustion and fluidising materials of the fluidised bed. From a peripheral flange 60 of the bottom casing part, tie rods 62 extend upwards to secure a top frame 64 abutting onto the main frame 52. Between the ceramic side walls are ceramic corner posts 66 of a precisely controlled height forming distance pieces that, when the top frame 64 is bolted down by the tie rods 62, determines the degree of compression of the tube end ceramic seals 48 and also of ceramic fibre gaskets 68 laid between successive wall blocks. Forming the top of the chamber is a ceramic-lined waste gas duct 70 of sufficient height to prevent the carry-over of sand or other medium-sized particles from the fluidised bed during operation.
As in the example of FIG. 3, header boxes 72 are provided at the casing side walls and are sealed by ceramic fibre gaskets 74 when bolted to the main frame 52. FIG. 4 does not show the means for internal tube support and for limiting or preventing carry-over of solid material leaking into the ceramic tubes as these means have already been described above.
Because of the arrangement of mutually transverse banks of tubes in FIG. 4, header boxes are provided at all four sides of the casing, although only one box is shown for sake of clarity. Depending on the requirements of the user these boxes may be connected in different ways.
If large quantities of fluid at moderate temperatures, e.g. up to 350° C., are required then the header boxes of adjacent pairs of side walls can be connected together so that the two mutually transverse series of tubes provide two fluid passes in parallel.
If smaller quantities of fluid at higher temperatures, e.g. up to 800° C., are required then the two passes could be connected in series: the air or other gas to be heated would then flow through one series of parallel tubes between one opposed pair of headers and then to a third header leading to the other series of parallel tubes before exiting from the fourth header opposite that third header. This arrangement gives a simpler header box construction than would be needed if each pass utilised a pair of each series of parallel tubes, but because the volume of the fluid increases as it is heated, in the second pass its velocity would increase if both passes have the same number and size of tubes. The rectangular plan form of the fluidised bed can be elongated, however, so that with an optimum lateral tube spacing of both series of tubes, there is a greater total cross-sectional area available for the second pass than foeral tube spacing of both series of tubes, there is a greater total cross-sectional area available for the second pass than for the first pass as the fluid temperature rises and its own density decreases. The velocity through the second pass can then be held at a reasonable level to avoid an excessive pressure drop in the second pass as compared with the first pass.
Mention has already been made of the need to strengthen the ceramic tubes to withstand buffeting and prevent fracture within the fluidised bed. A further means by which this can be done and which can be used additionally to or independently of the internal reinforcing means already described, is illustrated in FIGS. 5 to 7. This takes the form of external supports 82 extending between adjacent tubes and in particular between mutually transverse tubes. The supports may be made of heat resistant metals or ceramic materials, depending upon their operating temperature, and have flexible bearing means through which they engage the ceramic tubes since direct contact from such rigid members might itself create local stresses that would fracture a tube.
Each support comprises arcuate backing elements 84 at opposite ends of a connecting web 86. The bearing means comprise ceramic fibre pads 88 supported in the backing elements which have inturned flanges 90 along their upper or lower free edges that form retaining recesses for the pads 88. The ceramic fibre pads are pre-compressed during manufacture and held rigidly in that state by a suitable setting resin that degrades when the pads are first used. As manufactured their thickness is somewhat less than the spacing between the arcuate backing elements and the associated tube, as indicated at 88a on the right-hand of FIG. 5. During the initial firing of the fluidised bed the setting resin burns out of the pad, e.g. at about 300° C., whereupon the ceramic fibres are able to expand to grip the ceramic tubes while providing cushioning between the tubes and the rigid supports. After this initial stage the tubes are resiliently restrained by the ceramic fibre pads so that some movement is still permitted if a force is experienced and damage to the tubes is effectively minimised.
The backing elements in most instances are so formed that they do not extend to the levels of the centres of their associated tubes where the tubes have supports engaging them both from above and from below so that the forces on the tube from the support elements are balanced. For the topmost or lowermost series of supports, where this balanced condition does not prevail, it is preferable to extend the backing elements to beyond the level of the centres of the tubes, as indicated by the support 82a shown at the right of FIG. 5 and in FIG. 7, so that when the ceramic fibre pads expand they grip the outside of the tube over an extent greater than half the circumference, thereby restraining the tube from excessive vertical movement. Where this is done, the flanges 90 on the backing element must be so arranged as to allow adequate clearance for assembly of the support on the tube.
The supports described are particularly effective in an arrangement in which they extend between mutually transverse tubes, because bending forces in the plane of one bank of tubes will be transmitted as axial forces to the adjacent banks of tubes by the connecting supports. If additional reinforcement is required against bending forces acting transversely to the planes of the banks of tubes, it is possible to provide further supports from the bottom bank of tubes to the floor of the chamber, and possibly similar supports from the top bank of tubes to a top wall or to the top duct of the chamber.
Alternative end seal arrangements for the heat exchanger tubes are illustrated in FIGS. 8 to 12. Parts already described are indicated by the same reference numbers.
In FIG. 8 the previously described support rod 12 of each tube is extended beyond the side walls 2 and the apertured end disc 14b is held by securing nut 15 against a flanged cap 17. The cylindrical portion 17a of the flanged cap is a loose fit within the end of the ceramic tube 6 so that it does not stress it but it is nevertheless located substantially coaxially with it. Tightening the nut 15 clamps the cap flange 17b against the chamber outer face with a gasket 30a interposed. The cap cylindrical portion 17a engages the end seals 22 radially and the cap can therefore support the seals against possible creep in successive expansion and contraction cycles. This arrangement is able to provide a very tight seal capable of withstanding pressure differences of several atmospheres between the two flows that are in heat exchange.
By way of illustration, FIG. 8 also shows a spacer disc 14' formed of a mesh body or a porous mass, as mentioned above.
FIG. 9 shows how, where a header box is provided (as in FIG. 3), this can bear against the flanges 17b of the caps with additional gaskets 30b interposed. FIG. 9 also shows a further modification in that the cap is secured and the axial pressure applied to the seals 22 by the header tube plate 26. The additional gaskets 30a are located centrally by annular shoulders 26a of the tube plate. With this clamping method, if an internal tube support arrangement is provided as already described, the supporting rod 12 need not be fixed to the flanged cap 17 and FIG. 9 shows a free-floating arrangement. Displacements of the rod are limited by the caps 17 at opposite ends of the tube 6, which form stops for the end discs 14, but a sufficient gap is left for all thermal expansion movements.
In a relatively low pressure system, the flanged caps 17 compressing the seals 22 can be axially located by the side walls themselves. FIG. 10 shows a retaining pin 102 held in accurately positioned holes 104 in the wall blocks 2a and bearing against the cap flange 17b. If a supporting rod arrangement is provided, its displacements can be limited by the pins or by the flanged caps 17.
An alternative low pressure system is shown in FIGS. 11 and 12, where tabs 106 of a high-temperature alloy fit recesses 108 in the edges of the wall blocks 2a and have rear lips 110 that are retained in a channel 112 along the edge of the block 2a (the primary purpose of the channels 112 is to locate the ceramic fibre seals that are laid between adjoining wall blocks). Slots 114 in the outer ends of the tabs are engaged by the tube end caps 17 that have slots 116 in their flanges 17b through which the end tongues 118 of the tabs can be passed. During assembly, after a group of wall blocks 2a and tabs 106 are assembled, the tubes 6 and their seals 10,22 are fitted. The end gaskets 30a, which are also slotted to fit over the tabs 106, are put in place and the flanged caps 17 are inserted through the end seals 22 into the tubes, with the flange slots 116 oriented to slide over the tab tongues 118. When axially positioned, the caps are rotated to trap their flanges 17b in the tab slots 114, as shown in FIG. 12, the caps 17 then holding the seals 22 compressed.
The constructions described above may be used for a variety of applications. One particular example is to provide hot air, e.g. for industrial process applications, and if required a heated air flow at temperatures up to 800° C. can be provided for such purposes as drying.
It has already been mentioned that the use of the invention is not necessarily restricted to fluidised bed applications. The arrangement of the banks of tubes in mutually transverse series in particular is a feature that can be used to good effect in gas to gas heat exchangers, for example, where compactness of the heat exchanger is an important factor. Also, if it is required to install the heat exchanger in an existing conduit where the flow velocity is relatively slow, a large waste gas duct for example, the relatively closely packed mutually transverse banks of tubes can restrict the cross-section so as to increase considerably the flow velocity in the conduit and thereby improve the heat transfer rate. | A heat exchanger for high temperature operation has a ceramic-walled chamber traversed by ceramic tubes and is capable of use inter alia in fluidised bed applications. The tubes are arranged in series of successive banks and to give a compact arrangement the successive banks of tubes at different levels are disposed transversely to each other. The tubes may have internal and external reinforcing means to allow them to withstand the loads imposed by the fluidised bed and generally to allow longer tubes to be used in ceramic constructions. The internal reinforcing means may also provide restrictions that in fluidised bed applications can function to minimise the effects of tube wall fracture by reducing carry-over of bed particles seeping into the tubes. For improved end sealing, means can be provided to hold resilient ceramic seals compressed against the tube ends while permitting axial thermal movement of the tubes. | 8 |
This is a continuation in part of U.S. application Ser. No. 07/048,187, filed May 11, 1987, now U.S. Pat. No. 4,912,200.
BACKGROUND OF THE INVENTION
The present invention relates to extraction of granulocyte/macrophage colony stimulating factor (GM-CSF) from GM-CSF-expressing bacteria.
Granulocyte/macrophage colony stimulating factor is believed to be a potential therapeutic agent against infection and cancer. Clinical testing and widespread use of GM-CSF have been delayed owing to the unavailability of sufficient quantities of the material and the great expense of obtaining GM-CSF from natural sources. Recombinant DNA techniques have been used to create bacteria capable of expressing GM-CSF; see, for example, DeLamarter et al., EMBO J., Vol. 4, 2575-2581 (1985). Fermentation of such bacteria is expected to yield sufficient quantities of GM-CSF at substantially lower cost than would be possible utilizing natural sources of GM-CSF. However, clinical use of GM-CSF also requires high purity material that is not contaminated by cell constituents or cell debris of the GM-CSF-expressing bacteria. Contamination by such impurities could result in adverse reactions or in test results that are not reproducible. Accordingly, extraction of GM-CSF from the cells of GM-CSF-expressing bacteria in sufficiently high purity and yield for clinical use has been a major problem.
SUMMARY OF THE INVENTION
The present invention is based on the discovery that GM-CSF can be extracted from GM-CSF-expressing bacteria in high yield and purity by treating a suspension of GM-CSF-containing bacterial cells with an acid and an enhancing agent, or with an acid that is itself an enhancing agent, removing and discarding substantially all of the suspension liquid from the cells, preparing a second suspension of the treated cells, neutralizing said second suspension and separating the GM-CSF-containing liquid from the suspended cells. In accordance with the method of the present invention, GM-CSF is obtained from the cells without the need for mechanical or enzymatic disruption of the cell surface. The method of this invention allows recovery of GM-CSF in a manner which significantly reduces contamination by cell constituents, and subsequent purification is easier and less expensive.
The acid in the killing step is supplemented with an "enhancing agent" that increases the kill at a given pH and that also preferably helps the escape of GM-CSF from the cells.
The word "neutralizing" in the foregoing paragraph means that the second suspension is rendered approximately neutral (e.g. pH 6.0 to 8.0) or weakly alkaline (e.g. up to about pH 9.0).
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a construction map of plasmid pAKG-151.
DETAILED DESCRIPTION
The present invention provides a method for extracting GM-CSF from GM-CSF-expressing bacterial cells comprising:
(a) treating a suspension of GM-CSF-containing bacterial cells with an acid and an enhancing agent, or with an acid that is itself an enhancing agent;
(b) removing substantially all of the suspension liquid from the treated cells;
(c) preparing a second suspension of the treated cells;
(d) neutralizing said second suspension; and
(e) separating the GM-CSF-containing liquid from the suspended treated cells.
In carrying out the method of the present invention, acid is added to a suspension of GM-CSF-expressing cells to adjust the pH to a lethal value for the cells, i.e. to about 1.5 to 3.0, preferably to about 2.0 to 2.2. Examples of suitable acids that can be utilized in this invention are hydrochloric acid, nitric acid, phosphoric acid and sulfuric acid. Phosphoric acid is the preferred acid.
It should be noted that acid alone at pH 3.0 will kill the bacteria, but the low pH required for complete kill (down to pH 1.5) can cause damage to the GM-CSF by denaturation or decomposition (e.g. deamination). However, the use of an "enhancing agent" provides complete kill of the bacteria at a higher pH, e.g. in particular 2.0 to 2.2, where the likelihood of damage to the GM-CSF is much lower. Killing all the bacteria at this stage is highly desirable to ensure containment of a genetically-engineered microorganism.
The enhancing agent can itself be an acid, e.g. trichloroacetic acid, when it may be the sole acid used in the killing step.
The use of an enhancing agent not only aids in killing the bacterial cells but also often serves to improve the yield of extracted GM-CSF. Examples of suitable enhancing agents include chaotropic ions (or compounds providing them), such as trichloroacetate, perchlorate, thiocyanate and guanidinium; non-chaotropic salts, such as sodium chloride, sodium phosphate; and non-ionic chaotropes such as urea. Chaotropic ions are the preferred enhancing agents. Trichloroacetate is the most preferred enhancing agent (about 0.1M to 2.0M depending on such variables as cell density, pH and salt composition).
When the enhancing agent is a chaotropic ion it may be added either as a chaotropic salt, such as sodium thiocyanate or guanidinium chloride, or as a chaotropic acid, such as trichloroacetic acid or perchloric acid. If a chaotropic acid is used, then less or none of the other acid may be necessary.
In one embodiment of the acidification step of the method of this invention, phosphoric acid is added to the suspension to lower the pH to about 4 to 5, preferably 4.5, and then trichloroacetic acid is added to lower the pH to about 2.0.
If the temperature is too low then the bacteria will not be killed fast enough during the acid treatment. If the temperature is too high then GM-CSF may be altered. The temperature range for the acid treatment should be from about 10° C. to about 40° C., and preferably about 25° C.
After treating the cell suspension with acid and also with an enhancing agent, all subsequent steps of the method of this invention are carried out at a temperature of from about 0° C. to about 40° C., preferably 0° C. to 4° C.
After the cell suspension is treated with an acid (and an enhancing agent), to kill the bacterial cells, the cells are separated from the treatment liquid by microfiltration, centrifugation or the like, preferably by centrifugation, and resuspended in an aqueous buffer solution or in water. Examples of buffers that may be used in resuspending the pellet are sodium phosphate, potassium phosphate and tris (hydroxymethyl) aminomethane hydrochloride. Preferred buffers are sodium phosphate and especially tris (hydroxymethyl) aminomethane hydrochloride.
The cell suspension is neutralized to a pH of about 6.0 to 9.0, preferably 7.2 to 7.6. Examples of suitable bases that may be used in the neutralization step are sodium hydroxide, potassium hydroxide and the like.
Examples of bacteria that can be altered by recombinant DNA techniques to produce GM-CSF and from which GM-CSF may then be extracted using the method of the present invention are E. coli, Bacillus subtilis, Streptomyces coelicolor, and the like. The preferred bacterium is E. coli.
The method of the present invention may be used with bacteria that express different forms of GM-CSF, for example human GM-CSF [Lee et al., Proc. Natl. Acad. Sci. USA, Vol. 82, 4060-4064 (1985)], or murine GM-CSF [Burgess et al., J. Biol. Chem., Vol. 252, 1998-2033 (1977)].
The following Example describes the invention in detail. It will be apparent to those skilled in the art that modification of materials and methods may be practiced without departing from the purpose and intent of this disclosure.
EXAMPLE
The human GM-CSF expression plasmid, pAKG-151 used in this example consists of about 3800 base pairs and includes the following sequences (see FIG. 1):
(a) The double tandem promoter lpp/lac linked to the ompA signal sequence; Ghrayeb, et al., EMBO J., Vol. 3 (10), 2437-2442 (1984).
(b) The coding sequence for mature Hu-GM-CSF; See Lee et al., Proc. Natl. Acad. Sci. USA, Vol. 82, 4360-4364 (July 1985). The 5'-end of this coding sequence is fused with the 3'-end of the ompA signal coding sequence.
(c) The lac i gene for the expression of the lac repressor; Farabaugh, Nature, Vol. 274, 765-769 (Aug. 24, 1978).
(d) The temperature-sensitive replicon, rep cop Ts, derived from the plasmid pVU 208; Hakkart et al., Mol. Gen. Genet.; Vol. 183, 326-332 (1981).
(e) The kan r gene for the expression of aminoglycoside 3'-phosphotransferase II; Beck, et al., Gene 19, 327-336 (1982).
Cultivate a culture of E. coli strain 294 harboring the plasmid pAKG-151 in 200 ml of broth contained in a 2 liter baffled shake-flask at 30° C. The broth consists of 30 g/l of casein hydrolysate, 20 g/l of yeast extract, 20 g/l of glycerol, 10 mg/l of kanamycin, 5 g/l KH 2 PO 4 , 1 g/l MgSO 4 .7H 2 O, 0.1 ml/l of an antifoam agent, and water. The initial pH is adjusted to 7.0 with sodium hydroxide. Agitate until the cellular density of the culture reaches about 4 optical density units (lightpath 1 cm, 660 μm). Add 0.4 mM of isopropyl-β-D-thiogalactoside and continue the fermentation for about 3 hours attaining cellular density of about 9 optical density units. Then add 85% phosphoric acid to pH 4.0 followed by 50% trichloroacetic acid to pH 2.0. Agitate the acidified suspension for 1 hour at 30° C., centrifuge the suspension, discard the supernatant and resuspend the bacterial pellet in 0.1M sodium phosphate buffer pH 8.5 or in Tris.HCl buffer pH 8.5. The pH of the resulting suspension is adjusted to pH 7.0 to 7.5 with 1N sodium hydroxide. Adjust the final biomass concentration of the neutral suspension to correspond to about 30 optical density units of untreated culture. Agitate the neutral suspension for 30 minutes at 4° C., centrifuge, and discard the pellet. The supernatant contains extracted recombinant human granulocyte macrophage colony stimulating factor (GM-CSF). | A method of extracting granulocyte/macrophage colony stimulating factor (GM-CSF) from GM-SCF-expressing bacterial cells comprising treating a suspension of GM-CSF-containing bacterial cells with an acid and an enhancing agent, or with an acid that is itself an enhancing agent, removing substantially all of the suspension liquid from the cells, preparing a second suspension of the acidified cells, neutralizing said second suspension, and separating the GM-CSF-containing liquid from the suspended cells. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to a process and apparatus for stopping the attenuating action of a draw frame whenever an end or sliver passing therethrough breaks or otherwise fails properly to pass between the drafting rolls of the machine.
As is known, draw frames are employed to attenuate, parallelize and blend a plurality of slivers or ends, thus producing a combined sliver or roving representative of the characteristics of the various slivers which have been combined. In these machines a plurality of fibers made from varying grades of cotton or other materials is fed simultaneously, in parallel fashion, through the drawing rolls of the machine. The emerging, combined, single sliver or roving thus represents a true mixture of all of the fibers fed into the apparatus.
The machines in question also customarily have been equipped with suction hoods over the entire drafting sections thereof. These hoods or compartments are connected to a suction system leading to a collector for dust, fly, trash and the like which may be discharged during the drafting operation. In view of this arrangement whenever one of the slivers or ends being fed into the draw frame breaks, that end is drawn by the suction away from the normal flow of the material being drafted and proceeds to the collector via the suction fan. It has been found that ends or slivers may break in these machines and go unnoticed for a considerable length of time. This results in the production of light-weight, unsuitable sliver, the short weight of which eventually is reflected in the finished yarn. Also, if permitted to go on for a long enough time, these down ends cause chokes in the suction system. So far as I am aware, there heretofore has been no suitable way to warn the operator that an end is down inside the hood and that the machine should be stopped.
My invention relates to means automatically to shut down the drafting frame whenever an end or sliver mis-feeds or breaks.
Briefly, my invention comprises a sensor having a field of influence located at a point in the suction system by which a broken sliver passes on its way out of the apparatus, into the collector. The field of influence through which the broken end passes generates a signal upon the presence of the end passing through said field of influence. Further, in view of the fact that during normal operation of draw frames of the kind described, there is a discharge of fly, dust, trash and the like, I so design the sensor that it is responsive only to the presence of sliver as distinguished from the aforementioned particles being discharged.
In view of the foregoing it will be seen that an object of my invention is to provide an economical, efficient process and apparatus for automatically stopping draw frames and the like upon the mis-drawing or breaking of an end or sliver passing therethrough.
A more detailed object is to provide a guide for the sliver located in the suction duct which is effective to cause the broken end to pass into the field of influence of a sensor, thus assuring that the sensor produces a signal indicative of the presence of a broken end.
Another object is to provide a process of the character designated in which a broken end is moved away from the normal path of movement of the ends passing through the drawing apparatus, preferably generally normal to said path, passed through a field of influence, thus to generate a signal, and using that signal to shut down the drawing frame and to shut down the suction fan, if each individual draw frame is equipped with a suction fan as distinguished from being tied into a system where one fan serves more than one draw frame.
DESCRIPTION OF THE DRAWINGS
Apparatus illustrating the constructional features of my invention and which may also be used to carry out my improved process is shown in the accompanying drawings forming a part of this application, in which:
FIG. 1 is a somewhat diagrammatic, detail fragmental view of a more or less conventional draw frame taken generally along line 1--1 of FIG. 2 and showing my invention in association therewith;
FIG. 2 is a detail, fragmental view taken generally along line 2--2 of FIG. 1;
FIG. 3 is a detail, fragmental view taken generally along line 3--3 of FIG. 1;
FIG. 4 is a fragmental detail view taken along line 4--4 of FIG. 1;
FIG. 5 is an isometric view of one form of sensor which may be employed as a part of my invention;
FIG. 6 is a wholly diagrammatic wiring diagram; and,
FIG. 7 is a wholly diagrammatic wiring diagram illustrating the delay circuitry for the sensor.
DETAILED DESCRIPTION
Referring now to the drawings for a better understanding of my invention, I will describe the same in association with a standard, commercially available form of draw frame. While I have selected a specific form of draw frame for the purpose of illustration, after my invention is fully understood it will be apparent that the same may be adaptable to various other drafting operations and machines.
In the drawings the draw frame is indicated generally by the numeral 10. As is understood, the draw frame comprises two groups of feed rolls 11 and 12. As seen in FIG. 2 each group of rolls 11 and 12 comprises drafting roll pairs indicated by the numerals 13, 14 and 16 in FIG. 2.
The rolls are mounted on the respective shafts as shown and are driven in the direction of the arrows 17a and 17b, FIG. 2. This is usually accomplished by the provision of gears 17c on each pair of the rolls 13, 14 and 16. One of the shafts, for instance, the lower shaft of each set, may be driven by gearing, not shown, from a single source of power. In the drawings I have illustrated this driving of the entire groups of rolls as being by means of a belt 17d driven by a draw frame motor 17e.
As is understood, also, the type of draw frame being described is provided with a fly, dust and trash collection hood indicated generally by the numeral 19. This hood surrounds the portion of the apparatus where the drafting is taking place. Connected to the upper portion of the hood is a duct 21. Duct 21 preferably leads downwardly and is connected at its lower end to the intake of a suction fan 22. The suction fan discharges into a collector 23. See FIG. 6. The suction fan is driven through a belt 24 by a motor 26. If desired, the outer wall of the duct 21 may be provided with a glass or other transparent cover 27 for an opening 28 through said wall. Air is admitted into the housing through the openings 30. The velocity of the air flow through the hood is greater than the linear rate of speed of the sliver while being drafted.
The foregoing is a description, generally, of a type of frame to which my invention is applicable.
As stated, my invention comprises apparatus and process of operating the frame so that it is shut down when an end breaks or otherwise enters the duct 21.
Adjacent a lower wall 29 forming part of the enclosure and projecting into the suction duct 21 I mount a plate-like guide member 31. This member is somewhat semi-funnel shaped and has sides 32 which slope upwardly as indicated in FIG. 3 from a low point indicated at 33.
At the low point 33 of the guide member 31 I place a sensor indicated by the numeral 34. While various types of sensors may be adequate for the purposes at hand, I prefer to use a photocell-type device which carries its own energy emitting source 36 and an energy-responsive element 37. In practice, I have found that a photocell sensor manufactured by Optron, Inc., 1201 Tappan Circle, Carrollton, Tex. 75006, identified as its part No. OPB730F is entirely suitable. Suffice it to say that the object of the sensor is to establish a field of influence adjacent the "neck" of the funnel-shaped member 31 so that, upon the presence of a broken or mis-drafted end or sliver S 1 in said area a signal is generated by the sensor. See FIG. 1.
In order to prevent the giving of false signals due to the passage through said zone of influence of fly, trash or dirt, the sensor 34 is in circuit with time delay means. Referring particularly to FIG. 7 of the drawings, I show the sensor 34 diagrammatically in circuit with devices capable of providing the delay. Thus, within the control box 41, or elsewhere if desired, I feed the signal from the sensor 34 to a shaper-timer indiated at T 1 . The signal is then sent to a reset timer T 2 and thence to a one-shot timer T 3 . Each of these timers may be purchased from Motorola, Inc., Post Office Box 20912, Phoenix, Ariz. 85036. The output of the one-shot timer is fed to the coil C 1 of a relay. The relay controls contact points C 2 which are in circuit with the motors 17e and 26 through the lines L 3 and L 4 as shown in FIGS. 6 and 7. A low voltage power supply, such as a 15 volt system indicated at P 1 powers the system as indicated in FIG. 7. A relay C 1 suitable for the purposes at hand may be purchased from American Zettler, 16881-3 Hale Ave., Irvine, Calif. 92705 under its part No. A2-1530-08-1.
From the foregoing it is now possible to explain the operation of my improved process and apparatus and more fully to understand the advantages thereof. As stated, a plurality of slivers or ends indicated by the numeral S is fed into the machine for drafting, for instance, from the side indicated by the arrow 40, FIG. 2. Normally, all of the ends pass through the drafting rolls and come out as a combined sliver or roving indicated by the letter R, FIG. 2. On occasions, one of the ends of slivers indicated at S 1 breaks or otherwise is drawn away from the normal path of movement of the slivers being drafted and hence, due to the flow of air through the housing, moves downwardly and into the suction duct 21. Due to the shape of the member 31 this sliver passes into the field of influence maintained by the sensor 34, hence giving a signal indicative of its presence therein. It will be seen that since the free end of the broken sliver is acted upon by the flowing stream of air in the system, the sliver moves substantially axially driving its travel through the field of influence. As indicated diagrammatically in FIG. 6, this signal is fed to a combined amplifier and motor control unit located diagrammatically at 41. Also as diagrammatically shown in FIG. 6 these signals are used to deenergize the motors 17e and 26 whenever a sliver is in the said field of influence.
From the foregoing it will be seen that I have devised an improved process and apparatus fully effective automatically to stop a draw frame whenever an end goes down. In actual practice my invention has proven to be extremely satisfactory. The prime object of eliminating the production of under-weight sliver is achieved thus reducing the overall cost and reducing the amount of sub-weight yarn spun from such sliver.
It might be mentioned that if desired a signal light 43, operated by suitable contacts in the control mechanism 41 may be provided atop the machine to indicate to the operator when the same is shut down.
While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof. | Disclosed is a process and apparatus for stopping the drawing action of a draw frame whenever sliver breaks. The sliver is pneumatically conveyed into the field of influence of a sensor which generates a signal indicating the presence of the broken sliver therein. This signal is used to stop the draw frame, thus eliminating the production of sub-weight sliver or roving. | 3 |
RELATED APPLICATION
This application claims priority to U.S. Provisional Patent Application Ser. No. 60/888,986, filed Feb. 9, 2007. The aforementioned application is incorporated herein by reference.
BACKGROUND OF THE INVENTION
Hearing impairment, to a greater or lesser extent, affects more than 30 million people in the United States, according to the American Academy of Audiology. Hearing impairment can affect its victim in a variety of ways, such as a reduced comprehension of conversation or spoken words, or reduced ability to hear and enjoy music.
Many technologies have been developed to reduce the impact of hearing impairment on those who suffer from it. These technologies include a variety of hearing aids, diagnostic techniques and related devices. Moreover, the improvement of the clarity and intelligibility of audio signals by means of electrical devices has been the object of much investigation, especially for applications in telephony, recording and playback of audio signals for the hearing impaired. The results of previous research in these areas is described in various patent applications, including the following commonly-owned applications: Provisional Patent Application 60/837,752 filed Aug. 15, 2006, patent application Ser. No. 11/188,519 filed Jul. 25, 2005, and patent application Ser. No. 10/864,691 filed Jun. 9, 2004. Application Ser. Nos. 11/188,519, and 10/864,691 are incorporated herein by reference.
The mechanisms of sound propagation and enhancement are complex phenomena which have been the subject of considerable study. While counter-intuitive in concept, researchers have discovered that under certain conditions, human hearing may be enhanced by the addition of noise, which may actually improve signal detection, an effect attributable to a phenomena known as stochastic resonance. Stochastic resonance occurs when random noise is added to a signal, often at very low levels, which enhances the signal to noise ratio in such a way as to drive normally inaudible or barely audible sounds, such as the quiet or softer sounds of a musical passage, above the detection threshold. Hence, at a given output volume setting on a system, such as a radio, the overall quality of the sound is improved, as opposed to the sound which would be heard by a listener who simply turned up the volume to hear a faint signal. In the latter situation, the listener would turn up the noise level as well, to the detriment of the overall quality of the system output.
With respect to hearing impaired individuals, hearing loss may occur over the entire range of audible frequencies or, alternately, over only a portion of or at a single frequency within the audible range. Accordingly, it would be desirable to have the capability of selecting a single frequency or a range of frequencies at which the resonance phenomenon described above occurs, preferably in a system which could be tuned by the user to compensate for his or her specific audio impairment.
SUMMARY OF THE INVENTION
An improved method, using either electrical or digital signal processing (dsp) for modifying an audio signal in an electrical circuit is disclosed which advances the art and overcomes the problems articulated above by providing a passive electrical device that, when connected in series with a transducer or other audio input device, provides an output audio signal with improved clarity and loudness characteristics. The improved method includes passing the signal through a toroidal coil inductor element designed to produce the improved characteristics. The audio signal with improved clarity and loudness is more intelligible to both listeners having normal hearing and to hearing impaired listeners than an audio signal that has not been modified by the device disclosed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of a sample of random noise generated by the Barkhausen properties of an inductor coil.
FIG. 2 is an illustration of a sample of speech wave pulses.
FIG. 3A is an illustration of quiet sound showing it falling below the normal human hearing detection threshold [after Wiesenfeld & Moss (1995)].
FIG. 3B is an illustration of the effects of stochastic resonance on signal detectability. [Wiesenfeld & Moss, supra].
FIG. 4 is an embodiment of the toroidal coil inductor element of the electrical device.
FIG. 5 is a schematic diagram of elements of the system of the present invention.
FIG. 6 is a schematic diagram of the testing circuit used to collect the data displayed in FIG. 7 .
FIG. 7 is a graph of the frequency spectrum of the output of an embodiment of the coil element when excited by a 1 kHz input signal.
FIG. 8 is a schematic diagram of the testing circuit used to collect the data displayed in FIGS. 9 , 10 and 11 .
FIG. 9 is a graph of the frequency spectrum of the output of the testing circuit without the coil element.
FIG. 10 is a graph of the frequency spectrum of the output of the testing circuit with the coil element.
FIG. 11 is a graph of the frequency spectrum of the output of the testing circuit with the coil element.
DETAILED DESCRIPTION
In prior pending patent applications, a coil has been disclosed for improving the clarity and intelligibility of speech reproduced by a telephone handset. The coil, initially designed for use with a telephone handset equipped with a Hearing Aid Compatible (HAC) coil, has been found to improve the clarity and intelligibility of sound when used without a telephone handset equipped with the HAC coil. In previous applications, the coil has been used in combination with an audio speaker to produce an output with improved clarity and intelligibility.
The present device differs from the previous applications in that it provides for use of the coil in combination with a microphone or other audio transducer to produce an audio signal with improved clarity and intelligibility that may then be recorded or transmitted by other standard means. The sound waves to be processed are converted to electrical signals by the transducer. The electrical signals are then modified by the coil and when converted back to audio, produce an audio signal with improved clarity and intelligibility characteristics.
Referring initially to FIG. 4 , a view of the coil element of the device is shown. The coil element 100 includes a toroidal core 102 and a winding 104 having a pre-selected number of turns 105 . The core 102 may be made in a variety of sizes and of a variety of materials including iron-bearing and other magnetic materials, and it may also consist largely of air.
Referring now to FIG. 5 , a schematic diagram of the electrical device 200 for modifying an audio signal is shown. The device 200 includes this coil element 100 and a transducer 202 for converting an electrical signal into an audio signal, which may be subsequently recorded and replayed. The transducer 202 may be a microphone, a speaker or other transducer of a type widely known in the art. The device 200 has lead 204 that may be electrically attached to recording devices or any other device configured for processing, storing or transmitting input audio signals.
Several electro-acoustic and magnetic characteristics of the coil may produce the improvement, either alone or in combination. These characteristics include harmonic distortion and the stochastic resonance of Barkhausen noise, which will be described in greater detail below.
Harmonic distortion is the redistribution of the energy of the audio signal among harmonics of the frequencies that make up the audio signal. The presence of optimally placed harmonics can enrich the auditory experience in a manner analogous to adding the harmonically related notes (for example, a third and fifth) or tones to the base tone of a chord. This may improve the clarity of speech and produce a more ‘euphonic’ (pleasant sound) represented in the audio signal.
The device was tested for harmonic distortion and other noise in one specific analysis by means of the test setup shown in FIG. 6 as test setup 300 . An oscillator 302 was used to drive a 1 kHz audio signal through the coil element 100 ; although, it is to be understood that this frequency (1 kHz) and the corresponding results are presented for purposes of illustration only and that analogous results are obtained using audio signals at other frequencies. The oscillator 302 in this test may represent a transducer that has been excited at 1 kHz by a sound wave of the same frequency. The output of the oscillator was recorded by analyzer 306 with the coil element or inductor 100 removed from the system and replaced with a straight electrical connection 304 . The output was also recorded by analyzer 306 with the coil element 100 electrically connected to the test circuit.
The output of the oscillator 302 and coil element 100 are shown in FIG. 7 . Chart 7 A displays the frequency spectrum of the output of the test setup when the coil element 100 has been removed. The peak 400 at 1 kHz is the signal created by oscillator 302 . In FIG. 7B , the harmonics 402 of the 1 kHz input frequency are more intense. The addition of the coil element 100 to the circuit spreads the 1 kHz signal across its harmonics. As shown in 7 B, the 3rd, 5th, 7th and 9th harmonics 402 have increased levels with the coil element in place. This type of coherent, harmonic enrichment distortion appears to make the original sounds more clear and intelligble to hearing-impaired listeners and in many cases more desirable in sound quality for non-impaired listeners without increasing the volume of the output. Indeed, the output volume could be turned down without compromising audio quality. In other words, the sound quality would increase at any listening level.
Another possible mechanism by which the coil improves the clarity and loudness of an audio signal is the introduction of one or more forms of noise. There is a small increase in noise with the application of the coil element to an audio signal. It cannot be attributed to thermal or Johnson-Nyquist noise. Thermal noise due to the coil element can only arise in the real part of the impedance which is the resistance of about 5 Ohms in the electrical configuration of this test method and coil sensitivity.
One possible mechanism is Barkhausen noise. Barkhausen noise is characteristic of magnetically permeable steel such as used in the construction of the coil herein disclosed. When a magnetic material is driven through its hysteresis curve by a magnetizing force (H), the magnetic flux density (B) does not vary smoothly with the magnetizing force. Instead it varies in small jumps, as can be seen more clearly in the following drawing, which shows flux density (B) as a function of magnetic field density (H):
Since each jump is a transient phenomenon, there is a noise spectrum associated with it. Observation of this effect is widely used in the steel milling industry to evaluate processing of the steel. In this context fairly high values of B and H are used. However, in the context of the coil element, the values are smaller, but the effect nevertheless exists. It occurs to some degree in all magnetic components.
Referring to FIG. 8 , the test setup shows a low-frequency generator being used to drive a low-frequency current through the winding, thus exciting the core. As the flux jumps occur, a voltage will be induced in the winding which will cause a noise current to flow. By measuring the voltage across a fixed resistance in series with the winding, while simultaneously rejecting the excitation (low-frequency) current it is possible to observe the effect.
The low-pass filter after the generator removes any harmonic distortion products from the generator. The high-pass filter ahead of the analyzer ensures that the low-frequency signal will not overload the analyzer. The spectrum is then measured with and without the low-frequency excitation.
On FIG. 9 , the coil element is replaced with a wire. The spectra with and without the low-frequency signal are identical. This verifies that there are no noise artifacts due to the excitation in the test setup.
On FIG. 10 , the coil element is present. The low-frequency excitation is set to 20 Hz. The increase in the noise from 3 KHz to 10 KHz can be clearly seen.
On FIG. 11 , the coil element is present. The low frequency excitation is set to 40 Hz. Again, the noise increase is clear, but it is greater, because twice as many flux jumps per unit time are present as a result of the doubling of the excitation frequency. The increase in the noise floor is about 10 dB, a non-trivial increase in magnitude.
When the desired signal itself is the source of excitation, it becomes very difficult to analytically separate the noise from the cause of the noise. The noise still occurs, but it is difficult to make a clear presentation. An important aspect of the noise is that it is caused by, and is therefore temporally coherent with the signal.
The noise which is added to the signal by this mechanism may play a role in the improvement of hearing threshold through an effect known as stochastic resonance.
Stochastic resonance is a general physical and biophysical phenomenon which can be observed and demonstrated in a variety of systems. It is demonstrable in a counterintuitive way, namely that adding noise to a system may actually improve the signal-to-noise ratio. It has been shown to operate to improve signal detection in neurological operations. This occurs when a system, in this case hearing, receives a signal which is just below what is required to excite it. By adding a small amount of noise (often astonishingly small) the system responds to the signal which was previously unable to elicit a response.
The phenomenon may be best illustrated by referring to FIGS. 1-3 . FIG. 1 depicts a typical audio pattern for the random noise generated by the Barkhausen properties of an inductor coil. These properties are characteristic to the inductor 100 and, at least to some extent, are dependent upon the core configuration, including its shape, size and material composition. As the electrical signal, which corresponds to the audio signal, passes through the inductor and drives it to saturation, by way of example, a series of speech wave impulses as shown in FIG. 2 , the noise signal is coherently related to the audio signal because, in fact, the noise results from the form of the audio signal driving the coil. As shown in greater detail in FIGS. 3A and 3B , via the stochastic resonance phenomenon, the presence of the coherently modulated random noise drives what would otherwise be an inaudible audio signal through a detection threshold so that it may become detectable. In the case of a hearing-impaired individual, by way of example, tests may determine specific frequencies at which hearing loss is observable, and the characteristics of the inductor may be selected such that signals generated at those frequencies may be modulated so as to become detectable to that individual.
Changes may be made in the above methods, devices and structures without departing from the scope hereof It should thus be noted that the matter contained in the above description and/or shown in the accompanying drawings should be interpreted as illustrative and not in an limited sense. The following claims are intended to cover all generic and specific features described herein, as well as all statements of the scope of the present method, device and structure, which, as a matter of language, might be said to fall therebetween. | An electroacoustical apparatus and method is described that alters the output properties of an audio device to improve the sound properties for both hearing impaired and normal hearing listeners. The device includes a coil element of specific design and may incorporate digital signal processing techniques to modify audio signal output. The electrical device and method of processing provides for the beneficial alteration of sound waves to an audio signal, and further modification of the audio signal to provide for improved loudness and clarity characteristics. The improved characteristics provide for greater intelligibility of the audio signal to persons with hearing impairments and to persons with normal hearing. | 7 |
FIELD OF THE INVENTION
The present invention relates to long-arm stitchers and, more particularly, to a control system for long-arm stitchers and the like.
RELATED ART
Conventional long-arm sewing machines are generally used for quilting and/or sewing fabrics that are not easily moved through a sewing machine. As such, a long-arm sewing machine is designed to move with respect to a workpiece that is held stationary on a frame. However, the workpieces generally include two outer layers and a filler material that is sewn between the outer layers. Often, the filler being stitched into the workpiece is uneven, thereby adding to difficulties for a stitch regulator to properly control a velocity of the stitcher with respect to the workpiece. Moreover, the stitch design of the workpiece may include several different stitch types and/or a stitch pattern that is not straight, thereby complicating the ability to control the stitch pattern. Accordingly, the velocity of stitcher movement with respect to the workpiece must be varied during stitching to maintain a proper stitch length or number of stitches per inch of the workpiece.
Typically, a stitch regulator is controlled by optical encoders that monitor the stitch pattern as it is being stitch into the workpiece. However, such encoders must be positioned adjacent the workpiece and may resultantly interfere with the stitching operation. In addition, optical encoders are costly and require a significant amount of assembly time. The assembly also generally includes harnesses and cabling to properly install the optical encoder.
As such, it is desirable to control a stitch regulator utilizing a less costly and more easily assembled system that does not interfere with the stitching process.
SUMMARY OF THE INVENTION
In one embodiment, a control system for a stitcher is provided that includes a motor driving the stitcher, and a stitch regulator in communication with and capable of altering a velocity of the motor. A controller is in communication with the stitch regulator; and at least one accelerometer is in communication with the controller to determine an acceleration of the stitcher with respect to a workpiece. A signal representing the acceleration of the stitcher with respect to the workpiece is communicated to the controller; and the operation of the stitch regulator is modified as necessary based on the signal.
In another embodiment, a stitcher is provided that includes a needle to stitch a workpiece, a motor to operate the needle, and a stitch regulator in communication with and capable of controlling a speed of the motor. A controller is in communication with the stitch regulator. The stitcher also includes at least one accelerometer in communication with the controller to determine an acceleration of the stitcher with respect to the workpiece. A signal representing the acceleration of the stitcher with respect to the workpiece is utilized to adjust the operation of the needle as necessary.
In a further embodiment a method of operating a stitcher is provided. The method includes providing a stitch regulator for controlling the operation of the stitcher, and providing an accelerometer in communication with the stitch regulator. An acceleration of the stitcher with respect to a workpiece is measured with the accelerometer, and a signal representing the acceleration of the stitcher is sent to the stitch regulator. The method further includes integrating the signal representing the acceleration of the stitcher to determine a velocity of the stitcher with respect to the workpiece, and controlling the stitch regulator utilizing the velocity of the stitcher with respect to the workpiece.
Although the present invention is described with respect to a long-arm stitcher, one of ordinary skill in the art would recognize that the present invention also has applicability with standard sewing machines and could be used in both a commercial and/or household setting. Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
FIG. 1 is a perspective view of a prior art long-arm stitcher.
FIG. 2 is a perspective view of the stitcher shown in FIG. 1 having an accelerometer.
FIG. 3 is an algorithm of a method of operating the stitcher shown in FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
FIG. 1 illustrates a standard long-arm stitcher 10 including a base 12 , an arm 14 , and a take up lever box 16 . Although the present invention is described with respect to a long-arm stitcher, one of ordinary skill in the art would recognize that the present invention is also applicable to standard sewing machines. Moreover, the present invention is capable of operating with both commercial and household long-arm stitchers and sewing machines. The arm 14 is coupled to the base 12 at a back end 18 of the stitcher 10 . A first portion 20 of the arm 14 extends upward from the base 12 , and a second portion 22 of the arm 14 extends from the first portion 20 substantially parallel to the base 12 . The take up lever box 16 is disposed on the arm 14 at a stitching end 24 of the stitcher 10 that is opposite the back end 18 . The stitching end 24 of the stitcher 10 forms a workspace 26 where a fabric is stitched by an operator of the stitcher 10 . The stitching end includes a needle bar 28 having a needle 30 inserted therein and a hopping foot 32 each extending downward toward a needle plate 34 disposed on the base 12 . The needle plate 34 is attached to a square throat plate 36 . The throat plate 36 is configured to be removed to provide access to a rotary hook assembly (not shown) positioned within the base 12 below the throat plate 36 .
During operation, the needle bar 28 moves up and down thereby moving the needle 30 to form a stitch in the fabric. The needle bar 28 can be adjusted up or down to provide a proper machine timing height. A small hole in the needle plate 34 restricts movement of the thread as the stitch is formed. The hopping foot 32 raises and lowers with the movement of the needle 30 to press and release the fabric as the stitch is formed. The hopping foot 32 is designed to be used with rulers and templates and has a height that can be adjusted for proper stitch formation. A control box 48 is provided to control the operation of the stitcher 10 .
The control box 48 includes a stitch regulator 50 that controls a speed of the needle 30 . Specifically, the needle speed is controlled to accommodate varying thicknesses of the workpiece and varying stitch types. The speed is further controlled to accommodate a stitch pattern that may not be linear.
FIG. 2 illustrates the stitcher 10 having at least one accelerometer 52 positioned on the second portion 22 of the arm 14 to measure an acceleration of the stitcher 10 . As will be appreciated by one of ordinary skill in the art, the at least one accelerometer 52 may be positioned at any location on stitcher 10 . In one embodiment, the accelerometer 52 measures a piezoelectric effect utilizing microscopic crystal structures that become stressed by accelerative forces, thereby causing a voltage to be generated. The voltage is used then used to determine acceleration. Alternatively, the accelerometer 52 may sense changes in capacitance between two microstructures in the accelerometer 52 . Specifically, if an accelerative force moves one of the structures, the capacitance changes. The change in capacitance is then converted to a voltage that is used to determine acceleration. In other embodiments, the accelerometer 52 may utilize hot air bubbles or light. In the exemplary embodiment, the at least one accelerometer 52 is one of a single two-axis accelerometer or includes two separate accelerometers, namely an x-axis accelerometer and a y-axis accelerometer. Accordingly, the accelerometer 52 is capable of measuring the acceleration of stitcher 10 in any of the x-axis and the y-axis. In the exemplary embodiment, the accelerometer 52 is a high accuracy, dual-axis digital inclinometer and accelerometer, model number ADIS16209, from Analog Devices; however, it will be appreciated that any off-the-shelf accelerometer would be acceptable for use with the stitcher 10 .
The accelerometer 52 is electronically coupled to the stitch regulator 50 and is configured to control the stitch regulator 50 based on the algorithm 100 shown in FIG. 3 . Specifically, at step 102 , the stitcher 10 is moved to a zero motion position and the accelerometer 52 is calibrated while the stitcher 10 is stationary. The stitcher 10 is then operated, at step 104 , to stitch a pattern in the workpiece. During the operation, the stitch regulator 50 controls a number of stitches per inch that are stitched into the workpiece.
At step 106 , a signal indicative of the stitcher's acceleration with respect to the workpiece is received from the accelerometer 52 . The signal is filtered with a low pass filter and sampling losses are removed therefrom, at step 108 , to determine an acceleration of the stitcher 10 in both the x-axis and the y-axis. While the present invention is described with respect to both the x-axis and the y-axis, as will be appreciated by one of ordinary skill in the art, the signal may only be indicative of the stitcher's acceleration in one of the x-axis or the y-axis. At step 110 , the acceleration signal is integrated to provide a vector velocity of the stitcher 10 in the x-axis and the y-axis, wherein the vector velocities include both a magnitude and a direction. The vector velocity in the x-axis and the vector velocity in the y-axis are summed, at step 112 , to provide a vector sum having both a magnitude and direction indicative of a velocity of the stitcher 10 with respect to the workpiece.
At step 114 , it is determined whether a position of the stitcher 10 is also desired. If the position is not desired 116 , the velocity of the stitcher 10 is used to determine a correction of the stitch regulator 50 , at step 118 . The stitcher 10 is then operated, at step 104 , to stitch a pattern in the workpiece, wherein the stitch regulator 50 controls the number of stitches per inch based on the velocity correction.
If the position of the stitcher 10 is desired 120 , the stitcher velocity is integrated, at step 122 , to provide a vector position of the stitcher 10 in the x-axis and the y-axis, wherein the vector positions include both a magnitude and a direction. The vector position in the x-axis and the vector position in the y-axis are summed, at step 124 , to provide a vector sum having both a magnitude and direction indicative of a position of the stitcher 10 with respect to the workpiece. The velocity and position of the stitcher 10 is then used to determine a correction of the stitch regulator 50 , at step 126 . The stitcher 10 is then operated, at step 104 , to stitch a pattern in the workpiece, wherein the stitch regulator 50 controls the number of stitches per inch based on the velocity and position corrections.
Accordingly, the present invention provides a means to regulate a speed of stitcher needle 30 utilizing the acceleration and position of the stitcher in the x-axis and/or y-axis. Specifically, by determining the acceleration of the stitcher 10 , a velocity and displacement of the stitcher 10 is determined and input into the stitch regulator 50 . As such, the needle 30 can be regulated based on a velocity and/or displacement of the stitcher 10 with respect to a workpiece, thereby enabling automatic correction of a stitch pattern.
As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents. | A stitcher is provided that includes a needle to stitch a workpiece, a motor to operate the needle, and a stitch regulator in communication with and capable of controlling a speed of the motor. A controller is in communication with the stitch regulator. The stitcher also includes at least one accelerometer in communication with the controller to determine an acceleration of the stitcher with respect to the workpiece. A signal representing the acceleration of the stitcher with respect to the workpiece is utilized to adjust the operation of the needle as necessary. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 10/146,080, entitled “Aerosol Forming Device for Use in Inhalation Therapy,” filed May 13, 2002, which is a continuation-in-part of U.S. patent application Ser. No. 10/057,198 entitled “Method and Device for Delivering a Physiologically Active Compound,” filed Oct. 26, 2001, Lloyd et al. and of U.S. patent application Ser. No. 10/057,197 entitled “Aerosol Generating Device and Method,” filed Oct. 26, 2001, Wensley et al., now U.S. Pat. No. 7,766,013, each of said application Ser. Nos. 10/146,080, 10/057,198, 10/057,197 further claims priority to U.S. Provisional Application Ser. No. 60/296,225 entitled “Aerosol Generating Device and Method,” filed Jun. 5, 2001, Wensley et al., the entire disclosures of which are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the inhalation delivery of aerosols containing small particles. Specifically, it relates to a device that forms drug containing aerosols for use in inhalation therapy.
BACKGROUND OF THE INVENTION
[0003] Currently, there are a number of approved devices for the inhalation delivery of drugs, including dry powder inhalers, nebulizers, and pressurized metered dose inhalers. Along with particular drugs, however, the devices also deliver a wide range of excipients.
[0004] It is desirable to provide a device that can produce aerosols in the absence of excipients. The provision of such a device is an object of the present invention.
SUMMARY OF THE INVENTION
[0005] The present invention relates to the inhalation delivery of aerosols containing small particles. Specifically, it relates to a device that forms drug containing aerosols for use in inhalation therapy.
[0006] In a device aspect of the present invention, a device for delivering drug containing aerosols for inhalation therapy is provided. The device includes a housing and an airway that has a gas/vapor mixing airway area. The airway further includes a subassembly, which has a metallic substrate coated on its surface with a composition comprising a drug.
[0007] Typically, the device further includes a heater system. Preferably, the heater system is an inductive heater system. More preferably, it is an inductive heating system having a ferrite torroid.
[0008] Typically, the airway contains a restricted cross-sectional area along the gas/vapor mixing area. Preferably, the airway further includes means for causing turbulence as air moves through the airway.
[0009] Typically, the drug has a decomposition index less than 0.15. Preferably, the drug has a decomposition index less than 0.10. More preferably, the drug has a decomposition index less than 0.05.
[0010] Typically, the drug of the composition is of one of the following classes: antibiotics, anticonvulsants, antidepressants, antiemetics, antihistamines, antiparkisonian drugs, antipsychotics, anxiolytics, drugs for erectile dysfunction, drugs for migraine headaches, drugs for the treatment of alcoholism, drugs for the treatment of addiction, muscle relaxants, nonsteroidal anti-inflammatories, opioids, other analgesics and stimulants.
[0011] Typically, where the drug is an antibiotic, it is selected from one of the following compounds: cefinetazole; cefazolin; cephalexin; cefoxitin; cephacetrile; cephaloglycin; cephaloridine; cephalosporins, such as cephalosporin C; cephalotin; cephamycins, such as cephamycin A, cephamycin B, and cephamycin C; cepharin; cephradine; ampicillin; amoxicillin; hetacillin; carfecillin; carindacillin; carbenicillin; amylpenicillin; azidocillin; benzylpenicillin; clometocillin; cloxacillin; cyclacillin; methicillin; nafcillin; 2-pentenylpenicillin; penicillins, such as penicillin N, penicillin O, penicillin S, penicillin V; chlorobutin penicillin; dicloxacillin; diphenicillin; heptylpenicillin; and metampicillin.
[0012] Typically, where the drug is an anticonvulsant, it is selected from one of the following compounds: gabapentin, tiagabine, and vigabatrin.
[0013] Typically, where the drug is an antidepressant, it is selected from one of the following compounds: amitriptyline, amoxapine, benmoxine, butriptyline, clomipramine, desipramine, dosulepin, doxepin, imipramine, kitanserin, lofepramine, medifoxamine, mianserin, maprotoline, mirtazapine, nortriptyline, protriptyline, trimipramine, viloxazine, citalopram, cotinine, duloxetine, fluoxetine, fluvoxamine, milnacipran, nisoxetine, paroxetine, reboxetine, sertraline, tianeptine, acetaphenazine, binedaline, brofaromine, cericlamine, clovoxamine, iproniazid, isocarboxazid, moclobemide, phenyhydrazine, phenelzine, selegiline, sibutramine, tranylcypromine, ademetionine, adrafinil, amesergide, amisulpride, amperozide, benactyzine, bupropion, caroxazone, gepirone, idazoxan, metralindole, milnacipran, minaprine, nefazodone, nomifensine, ritanserin, roxindole, S-adenosylmethionine, tofenacin, trazodone, tryptophan, venlafaxine, and zalospirone.
[0014] Typically, where the drug is an antiemetic, it is selected from one of the following compounds: alizapride, azasetron, benzquinamide, bromopride, buclizine, chlorpromazine, cinnarizine, clebopride, cyclizine, diphenhydramine, diphenidol, dolasetron methanesulfonate, droperidol, granisetron, hyoscine, lorazepam, metoclopramide, metopimazine, ondansetron, perphenazine, promethazine, prochlorperazine, scopolamine, triethylperazine, trifluoperazine, triflupromazine, trimethobenzamide, tropisetron, domeridone, and palonosetron.
[0015] Typically, where the drug is an antihistamine, it is selected from one of the following compounds: azatadine, brompheniramine, chlorpheniramine, clemastine, cyproheptadine, dexmedetomidine, diphenhydramine, doxylamine, hydroxyzine, cetrizine, fexofenadine, loratidine, and promethazine.
[0016] Typically, where the drug is an antiparkisonian drug, it is selected one of the following compounds: amantadine, baclofen, biperiden, benztropine, orphenadrine, procyclidine, trihexyphenidyl, levodopa, carbidopa, selegiline, deprenyl, andropinirole, apomorphine, benserazide, bromocriptine, budipine, cabergoline, dihydroergokryptine, eliprodil, eptastigmine, ergoline pramipexole, galanthamine, lazabemide, lisuride, mazindol, memantine, mofegiline, pergolike, pramipexole, propentofylline, rasagiline, remacemide, spheramine, terguride, entacapone, and tolcapone.
[0017] Typically, where the drug is an antipsychotic, it is selected from one of the following compounds: acetophenazine, alizapride, amperozide, benperidol, benzquinamide, bromperidol, buramate, butaperazine, carphenazine, carpipramine, chlorpromazine, chlorprothixene, clocapramine, clomacran, clopenthixol, clospirazine, clothiapine, cyamemazine, droperidol, flupenthixol, fluphenazine, fluspirilene, haloperidol, mesoridazine, metofenazate, molindrone, penfluridol, pericyazine, perphenazine, pimozide, pipamerone, piperacetazine, pipotiazine, prochlorperazine, promazine, remoxipride, sertindole, spiperone, sulpiride, thioridazine, thiothixene, trifluperidol, triflupromazine, trifluoperazine, ziprasidone, zotepine, zuclopenthixol, amisulpride, butaclamol, clozapine, melperone, olanzapine, quetiapine, and risperidone.
[0018] Typically, where the drug is an anxiolytic, it is selected from one of the following compounds: mecloqualone, medetomidine, metomidate, adinazolam, chlordiazepoxide, clobenzepam, flurazepam, lorazepam, loprazolam, midazolam, alpidem, alseroxlon, amphenidone, azacyclonol, bromisovalum, buspirone, calcium N-carboamoylaspartate, captodiamine, capuride, carbcloral, carbromal, chloral betaine, enciprazine, flesinoxan, ipsapiraone, lesopitron, loxapine, methaqualone, methprylon, propanolol, tandospirone, trazadone, zopiclone, and zolpidem.
[0019] Typically, where the drug is a drug for erectile dysfunction, it is selected from one of the following compounds: cialis (IC351), sildenafil, vardenafil, apomorphine, apomorphine diacetate, phentolamine, and yohimbine.
[0020] Typically, where the drug is a drug for migraine headache, it is selected from one of the following compounds: almotriptan, alperopride, codeine, dihydroergotamine, ergotamine, eletriptan, frovatriptan, isometheptene, lidocaine, lisuride, metoclopramide, naratriptan, oxycodone, propoxyphene, rizatriptan, sumatriptan, tolfenamic acid, zolmitriptan, amitriptyline, atenolol, clonidine, cyproheptadine, diltiazem, doxepin, fluoxetine, lisinopril, methysergide, metoprolol, nadolol, nortriptyline, paroxetine, pizotifen, pizotyline, propanolol, protriptyline, sertraline, timolol, and verapamil.
[0021] Typically, where the drug is a drug for the treatment of alcoholism, it is selected from one of the following compounds: naloxone, naltrexone, and disulfuram.
[0022] Typically, where the drug is a drug for the treatment of addiction it is buprenorphine.
[0023] Typically, where the drug is a muscle relaxant, it is selected from one of the following compounds: baclofen, cyclobenzaprine, orphenadrine, quinine, and tizanidine.
[0024] Typically, where the drug is a nonsteroidal anti-inflammatory, it is selected from one of the following compounds: aceclofenac, alminoprofen, amfenac, aminopropylori, amixetrine, benoxaprofen, bromfenac, bufexamac, carprofen, choline, salicylate, cinchophen, cinmetacin, clopriac, clometacin, diclofenac, etodolac, indoprofen, mazipredone, meclofenamate, piroxicam, pirprofen, and tolfenamate.
[0025] Typically, where the drug is an opioid, it is selected from one of the following compounds: alfentanil, allylprodine, alphaprodine, anileridine, benzylmorphine, bezitramide, buprenorphine, butorphanol, carbiphene, cipramadol, clonitazene, codeine, dextromoramide, dextropropoxyphene, diamorphine, dihydrocodeine, diphenoxylate, dipipanone, fentanyl, hydromorphone, L-alpha acetyl methadol, lofentanil, levorphanol, meperidine, methadone, meptazinol, metopon, morphine, nalbuphine, nalorphine, oxycodone, papavereturn, pethidine, pentazocine, phenazocine, remifentanil, sufentanil, and tramadol.
[0026] Typically, where the drug is an other analgesic it is selected from one of the following compounds: apazone, benzpiperylon, benzydramine, caffeine, clonixin, ethoheptazine, flupirtine, nefopam, orphenadrine, propacetamol, and propoxyphene.
[0027] Typically, where the drug is a stimulant, it is selected from one of the following compounds: amphetamine, brucine, caffeine, dexfenfluramine, dextroamphetamine, ephedrine, fenfluramine, mazindol, methyphenidate, pemoline, phentermine, and sibutramine.
[0028] In a method aspect of the present invention, a method of forming a drug containing aerosol for use in inhalation therapy is provided. The method includes heating a substrate coated with a composition comprising a drug to form a vapor and mixing the vapor with a volume of air such that an aerosol having particles is formed. The mass median aerodynamic diameter of the formed particles is stable for at least 1 s.
[0029] Typically, the substrate is heated by moving it through a heating zone. Preferably, the heating zone is primarily produced by eddy currents induced by an alternating magnetic field.
[0030] Typically, the formed aerosol includes about 10 9 particles/cc of air.
[0031] Typically, the drug of the composition is of one of the drugs or classes of drugs described above with respect to a device of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Further features and advantages will become apparent from the following description of various examples of the invention, as illustrated in the accompanying drawings in which:
[0033] FIG. 1 is a schematic diagram of the overall system for conducting experiments using a laboratory example of a device of the present invention;
[0034] FIG. 2 is a top, right end and front perspective view of the example depicted in FIG. 1 ;
[0035] FIG. 3 is a partial cross-sectional and partial schematic side view of the example shown in FIG. 2 ;
[0036] FIG. 4 is a partial cross-sectional and partial schematic end view of the example shown in FIG. 2 ;
[0037] FIG. 5 is a partial cross-sectional and partial schematic top view of the example shown in FIG. 2 ;
[0038] FIG. 6 is a schematic cross-sectional side view of an alternate example of the device of the present invention using an annunciating device;
[0039] FIG. 7 is a top, left end and front perspective views of the removable sub-assembly containing the compound and a movable slide of the example shown in FIG. 2 showing the sub-assembly being mounted within the slide;
[0040] FIG. 8 is a schematic view of the heating element of the example shown in FIG. 2 showing the electric drive circuit;
[0041] FIG. 9 is a schematic side view of a second example of the present invention using a venturi tube;
[0042] FIG. 10 is a schematic side view of a fourth example of the present invention using a thin-walled tube coated with the compound;
[0043] FIG. 11 is a schematic side end view of the example shown in FIG. 10 ;
[0044] FIG. 12 is a schematic side end view of the example shown in FIG. 10 showing an inductive heating system generating an alternating magnetic field;
[0045] FIG. 13 is a schematic side view of an alternate example of that shown in FIG. 10 using a flow restrictor within the thin-walled tube;
[0046] FIG. 14 is a schematic side view of a fifth example of the present invention using an expandable container for the compound;
[0047] FIG. 15 is a schematic side view of a sixth example of the present invention using a container for the compound in an inert atmosphere;
[0048] FIG. 16 is a schematic side view of the example shown in FIG. 15 using a re-circulation of the inert atmosphere over the compound's surface;
[0049] FIG. 17 is a schematic side view of a seventh example of the present invention using a tube containing particles coated with the compound;
[0050] FIG. 18 is a schematic side view of the example shown in FIG. 17 using a heating system to heat the gas passing over the coated particles;
[0051] FIG. 19 is a schematic side view of an eighth example of the present invention referred to herein as the “oven device”;
[0052] FIG. 20 is a schematic side view of an ninth example of the present invention using gradient heating;
[0053] FIG. 21 is a schematic side view of a tenth example of the present invention using a fine mesh screen coated with the compound;
[0054] FIG. 22 is a top, right end and front perspective view of the example shown in FIG. 21 ;
[0055] FIG. 23 is a plot of the rate of aggregation of smaller particles into larger ones;
[0056] FIG. 24 is a plot of the coagulation coefficient (K) versus particle size of the compound;
[0057] FIG. 25 is a plot of vapor pressure of various compounds, e.g., diphenyl ether, hexadecane, geranyl formate and caproic acid, versus temperature;
[0058] FIG. 26 is a plot of blood levels for both the IV dose and the inhalation dose administered to various dogs during the experiments using the system shown in FIG. 1 ;
[0059] FIG. 27 is a plot of calculated and experimental mass median diameter (MMD) versus compound mass in the range of 10 to 310 μg;
[0060] FIG. 28 is a plot of calculated and experimental MMD versus compound mass in the range of 10 to 310 μg; and
[0061] FIG. 29 is a plot of the theoretical size (diameter) of an aerosol as a function of the ratio of the vaporized compound to the volume of the mixing gas.
DETAILED DESCRIPTION
Definitions
[0062] “Aerodynamic diameter” of a given particle refers to the diameter of a spherical droplet with a density of 1 g/mL (the density of water) that has the same settling velocity as the given particle.
[0063] “Aerosol” refers to a suspension of solid or liquid particles in a gas.
[0064] “Decomposition index” refers to a number derived from an assay described in Example 7. The number is determined by subtracting the percent purity of the generated aerosol from 1.
[0065] “Drug” refers to any chemical compound that is used in the prevention, diagnosis, treatment, or cure of disease, for the relief of pain, or to control or improve any physiological or pathological disorder in humans or animals. Such compounds are oftentimes listed in the Physician's Desk Reference (Medical Economics Company, Inc. at Montvale, N.J., 56 th edition, 2002), which is herein incorporated by reference.
[0066] Exemplary drugs include the following: cannabanoid extracts from cannabis, THC, ketorolac, fentanyl, morphine, testosterone, ibuprofen, codeine, nicotine, Vitamin A, Vitamin E acetate, Vitamin E, nitroglycerin, pilocarpine, mescaline, testosterone enanthate, menthol, phencaramkde, methsuximide, eptastigmine, promethazine, procaine, retinol, lidocaine, trimeprazine, isosorbide dinitrate, timolol, methyprylon, etamiphyllin, propoxyphene, salmetrol, vitamin E succinate, methadone, oxprenolol, isoproterenol bitartrate, etaqualone, Vitamin D3, ethambutol, ritodrine, omoconazole, cocaine, lomustine, ketamine, ketoprofen, cilazaprol, propranolol, sufentanil, metaproterenol, prentoxapylline, testosterone proprionate, valproic acid, acebutolol, terbutaline, diazepam, topiramate, pentobarbital, alfentanil HCl, papaverine, nicergoline, fluconazole, zafirlukast, testosterone acetate, droperidol, atenolol, metoclopramide, enalapril, albuterol, ketotifen, isoproterenol, amiodarone HCl, zileuton, midazolam, oxycodone, cilostazol, propofol, nabilone, gabapentin, famotidine, lorezepam, naltrexone, acetaminophen, sumatriptan, bitolterol, nifedipine, Phenobarbital, phentolamine, 13-cis retinoic acid, droprenilamin HCl, amlodipine, caffeine, zopiclone, tramadol HCl, pirbuterol naloxone, meperidine HCl, trimethobenzamide, nalmefene, scopolamine, sildenafil, carbamazepine, procaterol HCl, methysergide, glutathione, olanzapine, zolpidem, levorphanol, buspirone and mixtures thereof.
[0067] Typically, the drug of the composition is of one of the following classes: antibiotics, anticonvulsants, antidepressants, antiemetics, antihistamines, antiparkisonian drugs, antipsychotics, anxiolytics, drugs for erectile dysfunction, drugs for migraine headaches, drugs for the treatment of alcoholism, drugs for the treatment of addiction, muscle relaxants, nonsteroidal anti-inflammatories, opioids, other analgesics, cannabanoids, and stimulants.
[0068] Typically, where the drug is an antibiotic, it is selected from one of the following compounds: cefmetazole; cefazolin; cephalexin; cefoxitin; cephacetrile; cephaloglycin; cephaloridine; cephalosporins, such as cephalosporin C; cephalotin; cephamycins, such as cephamycin A, cephamycin B, and cephamycin C; cepharin; cephradine; ampicillin; amoxicillin; hetacillin; carfecillin; carindacillin; carbenicillin; amylpenicillin; azidocillin; benzylpenicillin; clometocillin; cloxacillin; cyclacillin; methicillin; nafcillin; 2-pentenylpenicillin; penicillins, such as penicillin N, penicillin O, penicillin S, penicillin V; chlorobutin penicillin; dicloxacillin; diphenicillin; heptylpenicillin; and metampicillin.
[0069] Typically, where the drug is an anticonvulsant, it is selected from one of the following compounds: gabapentin, tiagabine, and vigabatrin.
[0070] Typically, where the drug is an antidepressant, it is selected from one of the following compounds: amitriptyline, amoxapine, benmoxine, butriptyline, clomipramine, desipramine, dosulepin, doxepin, imipramine, kitanserin, lofepramine, medifoxamine, mianserin, maprotoline, mirtazapine, nortriptyline, protriptyline, trimipramine, viloxazine, citalopram, cotinine, duloxetine, fluoxetine, fluvoxamine, milnacipran, nisoxetine, paroxetine, reboxetine, sertraline, tianeptine, acetaphenazine, binedaline, brofaromine, cericlamine, clovoxamine, iproniazid, isocarboxazid, moclobemide, phenyhydrazine, phenelzine, selegiline, sibutramine, tranylcypromine, ademetionine, adrafinil, amesergide, amisulpride, amperozide, benactyzine, bupropion, caroxazone, gepirone, idazoxan, metralindole, milnacipran, minaprine, nefazodone, nomifensine, ritanserin, roxindole, S-adenosylmethionine, tofenacin, trazodone, tryptophan, venlafaxine, and zalospirone.
[0071] Typically, where the drug is an antiemetic, it is selected from one of the following compounds: alizapride, azasetron, benzquinamide, bromopride, buclizine, chlorpromazine, cinnarizine, clebopride, cyclizine, diphenhydramine, diphenidol, dolasetron methanesulfonate, dronabinol, droperidol, granisetron, hyoscine, lorazepam, metoclopramide, metopimazine, ondansetron, perphenazine, promethazine, prochlorperazine, scopolamine, triethylperazine, trifluoperazine, triflupromazine, trimethobenzamide, tropisetron, domeridone, and palonosetron.
[0072] Typically, where the drug is an antihistamine, it is selected from one of the following compounds: azatadine, brompheniramine, chlorpheniramine, clemastine, cyproheptadine, dexmedetomidine, diphenhydramine, doxylamine, hydroxyzine, cetrizine, fexofenadine, loratidine, and promethazine.
[0073] Typically, where the drug is an antiparkisonian drug, it is selected one of the following compounds: amantadine, baclofen, biperiden, benztropine, orphenadrine, procyclidine, trihexyphenidyl, levodopa, carbidopa, selegiline, deprenyl, andropinirole, apomorphine, benserazide, bromocriptine, budipine, cabergoline, dihydroergokryptine, eliprodil, eptastigmine, ergoline pramipexole, galanthamine, lazabemide, lisuride, mazindol, memantine, mofegiline, pergolike, pramipexole, propentofylline, rasagiline, remacemide, spheramine, terguride, entacapone, and tolcapone.
[0074] Typically, where the drug is an antipsychotic, it is selected from one of the following compounds: acetophenazine, alizapride, amperozide, benperidol, benzquinamide, bromperidol, buramate, butaperazine, carphenazine, carpipramine, chlorpromazine, chlorprothixene, clocapramine, clomacran, clopenthixol, clospirazine, clothiapine, cyamemazine, droperidol, flupenthixol, fluphenazine, fluspirilene, haloperidol, mesoridazine, metofenazate, molindrone, penfluridol, pericyazine, perphenazine, pimozide, pipamerone, piperacetazine, pipotiazine, prochlorperazine, promazine, remoxipride, sertindole, spiperone, sulpiride, thioridazine, thiothixene, trifluperidol, triflupromazine, trifluoperazine, ziprasidone, zotepine, zuclopenthixol, amisulpride, butaclamol, clozapine, melperone, olanzapine, quetiapine, and risperidone.
[0075] Typically, where the drug is an anxiolytic, it is selected from one of the following compounds: mecloqualone, medetomidine, metomidate, adinazolam, chlordiazepoxide, clobenzepam, flurazepam, lorazepam, loprazolam, midazolam, alpidem, alseroxlon, amphenidone, azacyclonol, bromisovalum, buspirone, calcium N-carboamoylaspartate, captodiamine, capuride, carbcloral, carbromal, chloral betaine, enciprazine, flesinoxan, ipsapiraone, lesopitron, loxapine, methaqualone, methprylon, propanolol, tandospirone, trazadone, zopiclone, and zolpidem.
[0076] Typically, where the drug is a drug for erectile dysfunction, it is selected from one of the following compounds: cialis (IC351), sildenafil, vardenafil, apomorphine, apomorphine diacetate, phentolamine, and yohimbine.
[0077] Typically, where the drug is a drug for migraine headache, it is selected from one of the following compounds: almotriptan, alperopride, codeine, dihydroergotamine, ergotamine, eletriptan, frovatriptan, isometheptene, lidocaine, lisuride, metoclopramide, naratriptan, oxycodone, propoxyphene, rizatriptan, sumatriptan, tolfenamic acid, zolmitriptan, amitriptyline, atenolol, clonidine, cyproheptadine, diltiazem, doxepin, fluoxetine, lisinopril, methysergide, metoprolol, nadolol, nortriptyline, paroxetine, pizotifen, pizotyline, propanolol, protriptyline, sertraline, timolol, and verapamil.
[0078] Typically, where the drug is a drug for the treatment of alcoholism, it is selected from one of the following compounds: naloxone, naltrexone, and disulfuram.
[0079] Typically, where the drug is a drug for the treatment of addiction it is buprenorphine.
[0080] Typically, where the drug is a muscle relaxant, it is selected from one of the following compounds: baclofen, cyclobenzaprine, orphenadrine, quinine, and tizanidine.
[0081] Typically, where the drug is a nonsteroidal anti-inflammatory, it is selected from one of the following compounds: aceclofenac, alminoprofen, amfenac, aminopropylori, amixetrine, benoxaprofen, bromfenac, bufexamac, carprofen, choline, salicylate, cinchophen, cinmetacin, clopriac, clometacin, diclofenac, etodolac, indoprofen, mazipredone, meclofenamate, piroxicam, pirprofen, and tolfenamate.
[0082] Typically, where the drug is an opioid, it is selected from one of the following compounds: alfentanil, allylprodine, alphaprodine, anileridine, benzylmorphine, bezitramide, buprenorphine, butorphanol, carbiphene, cipramadol, clonitazene, codeine, dextromoramide, dextropropoxyphene, diamorphine, dihydrocodeine, diphenoxylate, dipipanone, fentanyl, hydromorphone, L-alpha acetyl methadol, lofentanil, levorphanol, meperidine, methadone, meptazinol, metopon, morphine, nalbuphine, nalorphine, oxycodone, papavereturn, pethidine, pentazocine, phenazocine, remifentanil, sufentanil, and tramadol.
[0083] Typically, where the drug is an other analgesic it is selected from one of the following compounds: apazone, benzpiperylon, benzydramine, caffeine, clonixin, ethoheptazine, flupirtine, nefopam, orphenadrine, propacetamol, and propoxyphene.
[0084] Typically, where the drug is a cannabanoid, it is tetrahydrocannabinol (e.g., delta-8 or delta-9).
[0085] Typically, where the drug is a stimulant, it is selected from one of the following compounds: amphetamine, brucine, caffeine, dexfenfluramine, dextroamphetamine, ephedrine, fenfluramine, mazindol, methyphenidate, pemoline, phentermine, and sibutramine.
[0086] “Drug degradation product” refers to a compound resulting from a chemical modification of a drug. The modification, for example, can be the result of a thermally or photochemically induced reaction. Such reactions include, without limitation, oxidation and hydrolysis.
[0087] “Mass median aerodynamic diameter” or “MMAD” of an aerosol refers to the aerodynamic diameter for which half the particulate mass of the aerosol is contributed by particles with an aerodynamic diameter larger than the MMAD and half by particles with an aerodynamic diameter smaller than the MMAD.
[0088] “Stable aerosol” refers to an aerosol where the MMAD of its constituent particles does not vary by more than 50% over a set period of time. For example, an aerosol with an MMAD of 100 nm is stable over 1 s, if at a time 1 second later it has an MMAD between 50 nm and 150 nm. Preferably, the MMAD does not vary by more than 25% over a set period of time. More preferably, the MMAD does not vary by more than 20%, 15%, 10% or 5% over time.
[0089] Aerosolization Device
[0090] Example 1 is described in terms of an in vivo dog experiment. The example, however, is easily modified to suit human inhalation primarily through increasing airflow through it.
[0091] Referring to FIGS. 1-8 , a first example (1) of an aerosolization device of the present invention will be described. The device 1 as shown in FIG. 1 is operably connected to flow meter 4 (e.g., a TSI 4100 flow meter). The readings from flow meter 4 are fed to the electronics within chassis 8 shown in FIG. 2 . Flow meter 4 is shown in FIG. 1 within a dotted line to indicate housing 10 . Device controller 20 includes Chembook model #N30W laptop computer having actuator switch 22 ( FIG. 3 ) and National Instruments I/O Board (model #SC2345) (not shown) that interfaces with computer 20 to control device 1 and to control the recording of all data collected during the experiments. A software program to carry out these functions was developed using National Instruments' Labview software program.
[0092] Connection between device 1 and the I/O board is accomplished with a cable (e.g., DB25, not shown). A standard power supply (e.g., Condor F15-15-A+ not shown) delivers power to device 1 . Inhalation controller 30 is used to control the rate and volume of inhalation through device 1 into an anesthetized dog through an endrotracheal tube 34 . Controller 30 has a programmable breath hold delay, at the end of which, exhaust valve 40 in exhaust line 42 opens and the dog is allowed to exhale. Filter 50 in line 42 measures the amount of exhaust and its composition to monitor any exhaled drug. The source air through inlet line 54 , inlet valve 58 , flow meter 4 and inlet orifice 59 is from a compressed air cylinder (not shown).
[0093] Now referring to FIGS. 3-5 and 7 , a dose of compound 60 is deposited onto thin, stainless steel foil 64 so that the thickness of compound 60 is less than 10 microns. In most cases, compound 60 is deposited by making a solution of the compound with an organic solvent. This mixture is then applied to the foil substrate with an automated pump system. As shown, the size of the entire foil 64 (e.g., alloy of 302 or 304 with 0.004 in. thickness) is 0.7 by 2.9 inches and the area in which compound 60 is deposited is 0.35 by 1.6 inches. Other foil materials can be used but stainless steel has an advantage over other materials like aluminum in that it has a much lower thermal conductivity value, while not appreciably increasing the thermal mass. A low thermal conductivity is helpful because the heat generated in foil 64 should stay in the area of interest (i.e., the heating/vaporization zone 70 ). Foil 64 should have a constant cross section, because otherwise the electrical currents induced by the heater will not be uniform. Foil 64 is held in frame 68 , made so that the trailing edge of foil 64 has no lip on movable slide 78 and so compound 60 , once mixed with the air, is free in a downstream direction as indicated by arrow 127 of FIG. 3 . Frame 68 is typically made of a non-conductive material to withstand moderate heat (e.g., 200° C.) and to be non-chemically reactive with the compound (e.g., DELRIN AF®), a copolymer of acetal and TEFLON®).
[0094] Sub-assembly 80 , shown in FIG. 7 , consists of frame 68 having compound ( 60 ) coated foil 64 mounted therein. Sub-assembly 80 is secured within movable slide 78 by setting each of the downstream, tapered ends of frame 68 to abut against small rods 86 protruding from each downstream end of slide 78 , as shown in FIG. 7 . Slide 78 is driven by stepper motor 88 , shown in FIG. 3 , that moves sub-assembly 80 containing compound 60 along the longitudinal axis of example 1. This, in turn, moves stainless steel foil 64 through an alternating magnetic field. (It is preferable for the magnetic field to be confined within heating/vaporization zone 70 , shown in FIG. 5 , as in this laboratory example.) Ferrite toroid 90 is used to direct the magnetic field and is placed below foil 64 (e.g., approximately 0.05 inches below). As shown in FIG. 5 , heated area 70 is approximately 0.15 by 0.4 inches, with the smaller dimension along the direction of travel from left to right (i.e., from the upstream to the downstream ends of device 1 ) and the large dimension across the direction of travel (i.e., the width of device 1 ).
[0095] Foil 64 functions as both a substrate for the drug to be delivered to the subject and the heating element for the vaporization of the drug. Heating element 64 is heated primarily by eddy currents induced by an alternating magnetic field. The alternating magnetic field is produced in ferrite toroid 90 (e.g., from Fair-Rite Company) with slit 94 (e.g., 0.10 in. wide), which was wrapped with coil 98 of copper magnet wire. When an alternating current is passed through coil 98 , an alternating magnetic field is produced in ferrite toroid 90 . A magnetic field fills the gap formed by slit 94 and magnetic field fringe lines 100 , shown in FIGS. 5 and 6 , extend out from toroid 90 . The magnetic field line fringe lines 100 intersect heating element 64 . When using a ferrite core, the alternating frequency of the field is limited to below 1 MHz. In this device, a frequency between 100 and 300 kHz is typically used.
[0096] The location and geometry of the eddy currents determine where foil 64 will be heated. Since magnetic field fringe lines 100 pass through foil 64 twice, once leaving ferrite toroid 90 and once returning, two rings of current are produced, and in opposite directions. One of the rings is formed around magnetic field lines 100 that leave toroid 90 and the other ring forms around magnetic field lines 100 that return toroid 90 . The rings of current overlap directly over the center of slit 94 . Since they were in opposite directions, they sum together. The greatest heating effect is therefore produced over the center of slit 94 .
[0097] Slide 78 and its contents are housed in airway 102 made up of upper airway section 104 and lower airway section 108 shown in FIG. 3 . Upper airway section 104 is removable and allows the insertion of movable slide 78 , sub-assembly 80 and foil 64 . Lower airway section 108 is mounted on top of chassis 8 that houses the electronics (not shown), magnetic field generator 110 , stepper motor 88 and position sensors (not shown). Referring again to FIG. 1 , mounted in upper airway section 104 is upstream passage 120 and inlet orifice 59 that couples upper airway section 104 to flow meter 4 . The readings from the flow meter 4 are fed to the electronics housed in chassis 8 . Additionally, at the downstream end of airway passage 102 , outlet 124 is connected to mouthpiece 126 . During administration of compound 60 to the dog, when joined to the system, air is forced through inlet line 54 , flow meter 4 , airway 102 , and outlet 124 into the dog.
[0098] Additionally, a pyrometer at the end of TC2 line 130 is located within airway 102 and is used to measure the temperature of foil 64 . Because of the specific geometry of the example shown in FIGS. 1-7 , the temperature reading of foil 64 is taken after heating zone 70 . Calibration of the thermal decay between heating zone 70 and the measurement area is required. Temperature data is collected and used for quality control and verification and not to control any heating parameters. A second temperature sensor is located at the end of TC1 line 132 in outlet 124 and is used to monitor the temperature of the air delivered to the dog.
[0099] In a preferred example of the experimental device, removable block 140 , mounted on upper airway section 104 , restricts a cross-sectional area of airway 102 and provides a specific mixing geometry therein. In this preferred example, airway 140 lowers the roof of upper airway section 104 (e.g., to within 0.04 inch of) with respect to foil 64 . Additionally, block 140 contains baffles (e.g., 31 steel rods 0.04 in. in diameter, not shown). The rods are oriented perpendicular to the foil and extend from the top of upper airway section 104 to within a small distance of the foil (e.g., 0.004 in.). The rods are placed in a staggered pattern and have sharp, squared off ends, which cause turbulence as air passes around them. This turbulence assures complete mixing of vaporized compounds with air passing through the device.
[0100] A second example ( 150 ) of an aerosolization device of the present invention, in which the cross-sectional area is also restricted along the gas/vapor mixing area, will be described in reference to FIG. 9 . In this example, venturi tube 152 within housing 10 having inlet 154 , outlet 156 includes a throat 158 between inlet 154 and outlet 156 , which is used to restrict the gas flow through venturi tube 152 . Additionally, a controller 160 is designed to control the flow of air passing through a valve 164 based on readings from the thermocouple 168 of the temperature of the air, which can be controlled by heater 166 .
[0101] Block 140 is located directly over heating zone 70 and creates a heating/vaporization/mixing zone. Prior to commencing aerosol generation, slide 78 is in the downstream position. Slide 78 , with its contents, is then drawn upstream into this heating/vaporization/mixing zone 70 as energy is applied to foil 64 through the inductive heater system described in detail below.
[0102] The device of the present invention is optionally equipped with an annunciating device. One of the many functions for the annunciating device is to alert the operator of the device that a compound is not being vaporized or is being improperly vaporized. The annunciating device can also be used to alert the operator that the gas flow rate is outside a desired range. FIG. 6 is a schematic diagram illustrating a third example of a hand held aerosolization device 180 of the present invention. As shown, device 180 includes many of the components of device 150 , discussed above, and additionally includes an annunciating device 170 . During the use of device 180 in which the patient's inhalation rate controls the airflow rate, a signal from annunciating device 170 would alert the patient to adjust the inhalation rate to the desired range. In this case, controller 160 would be connected to annunciating device 170 to send the necessary signal that the flow rate was not within the desired range.
[0103] The induction drive circuit 190 shown in FIG. 8 is used to drive the induction-heating element of device 1 . The purpose of circuit 190 is to produce an alternating current in drive coil 98 wrapped around ferrite core 90 . Circuit 190 consists of two P-channel transistors 200 and two N-channel MOSFET transistors 202 arranged in a bridge configuration. MOSFET transistors 200 and 202 connected to clock pulse generator 219 are turned on and off in pairs by D-type flip-flop 208 through MOSFET transistor drive circuit 210 . D-type flip-flop 208 is wired to cause the Q output of the flip-flop to alternately change state with the rising edge of the clock generation signal. One pair of MOSFET transistors 200 is connected to the Q output on D-type flip-flop 208 and the other pair, 202 , is connected to the Q-not output of flip-flop 208 . When Q is high (5 Volts), a low impedance connection is made between the D.C. power supply (not shown) and the series combination of drive coil 98 and the capacitor through the pair of MOSFET transistors 200 controlled by the Q output. When D-type flip-flop 208 changes state and Q-not is high, the low impedance connection from the power supply to the series combination drive coil 98 and capacitor 220 is reversed. Since flip-flop 208 changes state on the rising edge of the clock generation signal, two flip-flop changes are required for one complete drive cycle of the induction-heating element. The clock generation signal is typically set at twice the resonant frequency of the series combination of drive coil 90 and capacitor 220 . The clock signal frequency can be manually or automatically set.
[0104] A second example ( 150 ) of an aerosolization device of the present invention, in which the cross-sectional area is also restricted along the gas/vapor mixing area, will be described in reference to FIG. 9 . In this example, venturi tube 152 within housing 10 having inlet 154 , outlet 156 and throat 158 between inlet 154 and outlet 156 is used to restrict the gas flow through venturi tube 152 . Controller 160 is designed to control the flow of air passing through valve 164 based on readings from the thermocouple 168 of the temperature of the air as a result of heater 166 .
[0105] A fourth example ( 300 ) of an aerosolization device of the present invention will be described in reference to FIGS. 10 and 11 . A gas stream is passed into thin walled tube 302 having a coating ( 310 ) of compound 60 on its inside. The flow rate of the gas stream is controlled by valve 314 . The device of example 300 , as with others, allows for rapid heat-up using a resistive heating system ( 320 ) while controlling the flow direction of vaporized compound. After activating heating system 320 with actuator 330 , current is passed along tube 302 in the heating/vaporization zone 340 as the carrier gas (e.g., air, N 2 and the like) is passed through tube 302 and mixes with the resulting vapor.
[0106] FIG. 12 shows an alternative heating system to resistive heating system 320 used in connection with the fourth example. In this case, inductive heating system 350 consists of a plurality of ferrites 360 for conducting the magnetic flux to vaporize compound 310 .
[0107] FIG. 13 shows a variation on the fourth example in which flow restrictor 370 is mounted within thin-walled tube 302 by means of support 374 within a housing (not shown) to increase the flow of mixing gas across the surface of compound 310 .
[0108] A fifth example 400 of an aerosolization device of the present invention will be described in reference to FIG. 14 . For this example, compound 60 is placed within expandable container 402 (e.g., a foil pouch) and is heated by resistance heater 406 , which is activated by actuator 410 as shown in FIG. 14 . The vaporized compound generated is forced into container 420 through outlet passage 440 and mixed with the gas flowing through tube 404 . Additional steps are taken, when necessary, to preclude or retard decomposition of compound 60 . One such step is the removal or reduction of oxygen around 60 during the heat up period. This can be accomplished, for example, by sealing the small container housing in an inert atmosphere.
[0109] A sixth example 500 of an aerosolization device of the present invention will be described in reference to FIG. 15 . Compound 60 is placed in an inert atmosphere or under a vacuum in container 502 within housing 10 and is heated by resistance heater 504 upon being activated by actuator 508 as shown in FIG. 15 . Once compound 60 has become vaporized it can then be ejected through outlet passage 510 into the air stream passing through tube 520 .
[0110] FIG. 16 shows a variation of device 500 in which fan 530 recirculates the inert atmosphere over the surface of compound 60 . The inert gas from a compressed gas cylinder (not shown) enters through inlet 540 and one-way valve 550 and exits through outlet passage 510 into tube 502 .
[0111] A seventh example ( 600 ) of an aerosolization device of the present invention will be described in reference to FIG. 17 . A compound (not shown), such as compound 60 discussed above, is deposited onto a substrate in the form of discrete particles 602 (e.g., aluminum oxide (alumina), silica, coated silica, carbon, graphite, diatomaceous earth, and other packing materials commonly used in gas chromatography). The coated particles are placed within first tube 604 , sandwiched between filters 606 and 608 , and heated by resistance heater 610 , which is activated by actuator 620 . The resulting vapor from tube 604 is combined with the air or other gas passing through second tube 625 .
[0112] FIG. 18 shows a variation of device 600 in which resistance heater 630 heats the air prior to passing through first tube 604 and over discrete particles 602 .
[0113] An eighth example 700 of an aerosolization device of the present invention will be described in reference to FIG. 19 . Compound 60 is deposited into chamber 710 and is heated by resistance heater 715 , which is activated by actuator 720 . Upon heating, some of compound 60 is vaporized and ejected from chamber 710 by passing an inert gas entering housing 10 through inert gas inlet 725 and valve 728 across the surface of the compound. The mixture of inert gas and vaporized compound passes through passage 730 and is then mixed with a gas passing through tube 735 .
[0114] A ninth example 800 of an aerosolization device of the present invention will be described in reference to FIG. 20 . Thermally conductive substrate 802 is heated by resistance heater 810 at the upstream end of tube 820 , and the thermal energy is allowed to travel along substrate 802 . This produces, when observed in a particular location, a heat up rate that is determined from the characteristics of the thermally conductive substrate. By varying the material and its cross sectional area, it was possible to control the rate of heat up. The resistive heater is embedded in substrate 802 at one end. However, it could be embedded into both ends, or in a variety of positions along the substrate and still allow the temperature gradient to move along the carrier and/or substrate.
[0115] A tenth example 900 of an aerosolization device of the present invention will be described in reference to FIGS. 21 and 22 . Air is channeled through a fine mesh metal screen 902 on which drug is deposited. Screen 902 is positioned across airway passage 910 (e.g., constructed from 18 mm glass tubing). The two sides of the screen are electrically connected to charged capacitor 920 through silicon-controlled rectifier (SCR) 922 to make a circuit. The charge of the capacitor is calculated and set at a value such that, when actuator 930 closes SCR 922 , the energy from capacitor 920 is converted to a desired temperature rise in screen 902 .
[0116] General Considerations
[0117] The device of the present invention utilizes a flow of gas (e.g., air) across the surface of a compound ( 60 ) to sweep away vaporized molecules. This process drives vaporization as opposed to condensation and therefore enables aerosol formation at relatively moderate temperatures. Nicotine (1 mg, by 247° C./745 mm), for example, vaporized in less than 2 s at about 130° C. in a device of the present invention. Similarly, fentanyl (bp >300° C./760 mm) was vaporized around 190° C. in quantities up to 2 mg.
[0118] Purity of an aerosol produced using a device of the present invention is enhanced by limiting the time during which a compound ( 60 ) is exposed to elevated temperatures. This is accomplished by rapidly heating a thin film of the compound to vaporize it. The vapors are then immediately cooled upon entry into a carrier gas stream.
[0119] Typically, compound 60 is subjected to a temperature rise of at least 1,000° C./second. In certain cases, the compound is subjected to a temperature rise of at least 2,000° C./second, 5,000° C./second, 7,500° C. or 10,000° C./second. A rapid temperature rise within the compound is facilitated when it is coated as a thin film (e.g., between 10μ and 10 nm in thickness). The compound is oftentimes coated as a film between 5μ and 10 nm, 4μ and 10 nm, 3μ and 10 nm, 2μ and 10 nm, or even 1μ to 10 nm in thickness.
[0120] Rapid temperature rises and thin coatings ensure that compounds are substantially vaporized in a short time. Typically, greater than 0.1 mg, 0.25 mg, 0.5 mg, 0.75 mg or 1 mg of a compound is vaporized in less than 100 milliseconds from the start of heating. Oftentimes, the same amount of compound is vaporized in less than 75 milliseconds, 50 milliseconds, 25 milliseconds, or 10 milliseconds from the start of heating.
[0121] Examples of compounds that have benefited from rapid heating in a device of the present invention include lipophilic substance #87 and fentanyl. Lipophilic substance #87 decomposed by more than 90% when heated at 425° C. for 5 minutes, but only 20% when the temperature was lowered to 350° C. Decomposition of the substance was further lowered to about 12% when the heating time was decreased to 30 seconds and to less than 2% at 10-50 milliseconds. A fentanyl sample decomposed entirely when heated to 200° C. for 30 seconds, and only 15-30% decomposed when heated for 10 milliseconds. Vaporizing fentanyl in device 1 led to less than 0.1% decomposition.
[0122] An aerosol of the present invention contains particles having an MMAD between 10 nm and 1μ preferably 10 nm to 900 nm, 10 nm to 800 nm, 10 nm to 700 nm, 10 nm to 600 nm, 10 nm to 500 nm, 10 nm to 400 nm, 10 nm to 300 nm, 10 nm to 200 nm, or 10 nm to 100 nm. Particles are produced such that their size is stable for several seconds (e.g., 1 to 3 s). The aerosol particle size and subsequent stability is controlled by the rate of compound vaporization, the rate of carrier gas introduction, and the mixing of resultant vapors and the carrier gas. Such control is accomplished using a number of methods, including the following: (a) measuring the quantity and regulating the flow rate of the mixing air; and/or, (b) regulating the vaporization rate of the compound (e.g., by changing the energy transferred to the compound during the heating process or changing the amount of compound introduced into a heating region).
[0123] A desired particle size is achieved by mixing a compound in its vapor state into a volume of a carrier gas in a ratio such that, when the number concentration of the mixture reaches approximately 10 9 particles/mL, a particle that exists in a size range from 10 nm to 100 nm for 1 to 3 seconds results.
[0124] FIG. 23 is a plot of theoretical data calculated from a mathematical model. See “Aerosol Technology” W. C. Hinds, second edition 1999, Wiley, New York. It shows the time in seconds it takes for the number concentration of an aerosol to aggregate to half of its original value as a function of the particle concentration. For example, a 1.0 mg vaporized dose of a compound with a molecular weight of 200 that is mixed into 1 liter of air will have approximately 3×10 18 molecules (particles) in the liter. This results in a number concentration of 3×10 15 /cc. Extrapolating from FIG. 23 , one can see that it takes less than 10 milliseconds for the number of particles to halve in this example. Therefore, to insure uniform mixing of a vaporized compound, the mixing must occur in a very short time. FIG. 23 also shows that when the number concentration of the mixture reaches approximately 10 9 particles/cc, the particle size is “stable” for the purpose of drug delivery by inhalation.
[0125] FIG. 23 is for an aerosol having a Coagulation Coefficient (K) of 5×10 −16 meters 3 /second. This K value corresponds to a particle size of 200 nm. As the particle size changes, so can its K value. Table 1 below gives the K values for various particle sizes. As K increases, the time required for the aerosol to aggregate from a particular particle size to a larger particle size is reduced. As can be seen from Table 1 and FIG. 24 , when the particle is in the 10 nm to 100 nm range, the effect of a changing K value tends to accelerate the coagulation process towards 100 nm in size.
[0000]
TABLE 1
Coagulation Coefficient (×e −15
Particle size (diameter in nm)
meters 3 /second)
1
3.11
5
6.93
10
9.48
20
11.50
50
9.92
100
7.17
200
5.09
500
3.76
1000
3.35
2000
3.15
5000
3.04
10000
3.00
[0126] In creating an aerosol of a particular particle size, the ratio of mass of vaporized compound to the volume of the mixing gas is the controlling condition. By changing this ratio, the particle size can be manipulated (see FIG. 29 ). However, not all compounds and not all gases, with the same ratio will result in the same particle size distribution (PSD). Other factors must be known to be able to accurately predict the resultant particle size. A compound's density, polarity, and temperature are examples of some of these factors. Additionally, whether the compound is hydrophilic or hydrophobic will affect the eventual particle size, because this factor affects an aerosol's tendency to grow by taking on water from the surrounding environment.
[0127] In order to simplify the approach used to predict the resulting particle size, the following assumptions were made:
1. The compound is non polar (or has a weak polarity). 2. The compound is hydrophobic or hydrophilic with a mixing gas that is dry. 3. The resultant aerosol is at or close to standard temperature and pressure. 4. The coagulation coefficient is constant over the particle size range and therefore the number concentration that predicts the stability of the particle size is constant.
[0132] Consequently, the following variables are taken into consideration in predicting the resulting particle size:
1. The amount (in grams) of compound vaporized. 2. The volume of gas (in cc's) that the vaporized compound is mixed into. 3. The “stable” number concentration in number of particles/cc. 4. The geometric standard deviation (GSD) of the aerosol.
[0137] Where the GSD is 1, all of the particle sizes are the same size and therefore the calculation of particle size becomes a matter of dividing a compound's mass into the number of particles given by the number concentration and from there calculating the particle size diameter using the density of the compound. The problem becomes different, though, if the GSD is other than 1. As an aerosol changes from a GSD of 1 to a GSD of 1.35, the mass median diameter (MMD) will increase. MMD is the point of equilibrium where an equal mass of material exists in smaller diameter particles as exists in larger diameter particles. Since total mass is not changing as the GSD changes, and since there are large and small particles, the MMD must become larger as the GSD increases because the mass of a particle goes up as the cube of its diameter. Therefore larger particles, in effect, carry more weight and the MMD becomes larger to “balance” out the masses.
[0138] To determine the effect of a changing GSD, one can start with the formula for the mass per unit volume of an aerosol given a known MMD, GSD, density, and number concentration. The formula is from Finlay's “ The Mechanics of Inhaled Pharmaceutical Aerosols ” (2001, Academic press). Formula 2.39 states that the mass per unit volume of an aerosol is:
[0000] M =(ρ Nπ/ 6)(MMD) 3 exp[−9/2(ln σ g ) 2]
[0139] Where:
ρ=density in gm/cc N=Number concentration in particles/cc MMD=mass median diameter (in cm) σ g =the GSD M=the mass per unit volume of the aerosol in gms/cc
[0145] If the change in the MMD is considered as an aerosol changes from one GSD to another, while the density, number concentration, and the mass remain unchanged the following equality can be set up:
[0000] σ g Nπ/ 6(MMD 1 ) 3 exp[−9/2(ln σ g1 ) 2 ]=ρN π/6(MMD 2 ) 3 exp[−9/2(ln σ g2 ) 2 ]
[0000] simplifying:
[0000] (MMD 1 ) 3 exp[−9/2(ln σ g1 ) 2 ]=(MMD 2 ) 3 exp[−9/2(ln σ g2 ) 2 ]
[0000] Or
[0000] (MMD 1 ) 3 /(MMD 2 ) 3 =exp[−9/2(ln σ g2 ) 2 ]/exp[−9/2(ln σ g1 ) 2 ]
[0146] If one sets the GSD of case 1 to 1.0 then:
[0000] exp[−9/2(ln σ g1 ) 2 =1
[0147] And therefore:
[0000] (MMD 1 /MMD 2 ) 3 =exp[−9/2(ln σ g2 ) 2 ]
[0148] Or:
[0000] MMD 1 /MMD 2 =exp[−3/2(ln σ g2 ) 2 ]
[0149] It is advantageous to calculate the change in the MMD as the GSD changes. Solving for MMD 2 as a function of MMD 1 and the new GSD 2 yields:
[0000] MMD 2 =MMD 1 /exp[−3/2(ln σ g2 ) 2 ] for a σ g1 =1
[0150] To calculate MMD 1 , divide the compound's mass into the number of particles and then, calculate its diameter using the density of the compound.
[0000] MMD 1 =(6 C/ρNV ) 1/3 for an aerosol with a GSD of 1
[0151] Where:
C=the mass of the compound in gm's ρ=Density in gm/cc (as before) N=Number concentration in particles/cc (as before) V=volume of the mixing gas in cc
[0156] Insertion of MMD 1 into the above equation leads to:
[0000] MMD 2 =(6 C/ρNV π) 1/3 /[exp[−3/2(ln σ g2 ) 2 ], measured in centimeters.
[0157] A resultant MMD can be calculated from the number concentration, the mass of the compound, the compound density, the volume of the mixing gas, and the GSD of the aerosol.
[0158] The required vaporization rate depends on the particle size one wishes to create. If the particle size is in the 10 nm to 100 nm range, then-the compound, once vaporized, must be mixed, in most cases, into the largest possible volume of air. This volume of air is determined from lung physiology and can be assumed to have a reasonable upper limit of 2 liters. If the volume of air is limited to below 2 liters (e.g., 500 cc), too large a particle will result unless the dose is exceedingly small (e.g., less than 50 μg).
[0159] In the 10 nm to 100 nm range, doses of 1-2 mg are possible. If this dose is mixed into 2 liters of air, which will be inhaled in 1-2 seconds, the required, desired vaporization rate is in the range of about 0.5 to about 2 mg/second.
[0160] The first example of the present invention is shown in FIG. 1 and is the basic device through which the principles cited above have been demonstrated in the laboratory. This device is described in detail in the EXAMPLES.
[0161] In the second example of the present invention shown in FIG. 9 , the use of a reduced airway cross section increases the speed of the air across the compound's surface to about 10 meters/second. If complete mixing is to happen within 1 millisecond, then the distance the gas and vaporized mixture must travel to achieve complete mixing must be no longer than 10 millimeters. However, it is more desirable for complete mixing to happen before the compound has aggregated to a larger size, so a desirable mixing distance is typically about 1 millimeter or less.
[0162] In the fourth example of the present invention shown in FIGS. 10-13 , an aerosol having particles with an MMAD in the 10 nm to 100 nm range is generated by allowing air to sweep over a thin film of the compound during the heating process. This allows the compound to become vaporized at a lower temperature due to the lowering of the partial pressure of the compound near the surface of the film.
[0163] The fifth example shown in FIG. 14 , the sixth example shown in FIGS. 15 and 16 , and the eighth example shown in FIG. 19 overcome a problem with certain compounds that react rapidly with oxygen at elevated temperatures. To solve this problem, the compound is heated in an expandable container (fourth example), a small container housing under a vacuum or containing a small amount, e.g., about 1 to about 10 ml, of an inert gas (fifth example). Once a compound is vaporized and mixed with an inert gas while the gaseous mixture is maintained at a temperature sufficient to keep the compound in its vaporized state, the gaseous mixture is then injected into an air stream. The volume of inert gas can also be re-circulated over the surface of the heated compound to aid in its vaporization as shown in FIG. 16 . In the seventh example, the compound is introduced into the gas as a pure vapor. This involves vaporizing the compound in an oven or other container and then injecting the vapor into an air or other gas stream through one or more mixing nozzles.
[0164] In the sixth example shown in FIGS. 17-18 , gas is passed through a first tube and over discrete substrate particles, having a large surface area to mass ratio, and coated with the compound. The particles are heated as shown in FIG. 17 to vaporize the compound, or the gas is heated and the heated gas vaporizes the compound as shown in FIG. 18 . The gaseous mixture from the first tube is combined with the gas passing through second tube to rapidly cool the mixture before administering it to a patient.
[0165] The eighth example shown in FIG. 20 is a thermal gradient device that is similar to device 1 used in the laboratory experiments. This example also has a moving heating zone without any moving parts, accomplished by establishing a heat gradient that transverses from one end of the device to the other over time. As the heating zone moves, exposed portions of the compound are sequentially heated and vaporized. In this manner the vaporized compound can be introduced into a gas stream over time.
[0166] The ninth example shown in FIGS. 21-22 is the screen device and is preferred for generating a aerosols containing particles with an MMAD greater than 100 nm. In this example, air is channeled through a fine mesh screen upon which the drug to be administered to the patient has been deposited.
[0167] The examples above can create aerosols without significant drug decomposition. This is accomplished while maintaining a required vaporization rate for particle size control by employing a short duration heating cycle. An airflow over the surface of the-compound is established such that when the compound is heated and reaches the temperature where vaporization is first possible, the resulting compound vapors will immediately cool in the air. In the preferred examples, this is accomplished by extending the increased velocity and mixing region over an area that is larger than the heating zone region. As a result, precise control of temperature is not necessary since the compound vaporizes the instant its vaporization temperature is reached. Additionally because mixing is also present at the point of vaporization, cooling is accomplished quickly upon vaporization.
[0168] Application of the present invention to human inhalation drug delivery must accommodate constraints of the human body and breathing physiology. Many studies of particle deposition in the lung have been conducted in the fields of public health, environmental toxicology and radiation safety. Most of the models and the in vivo data collected from those studies, relate to the exposure of people to aerosols homogeneously distributed in the air that they breathe, where the subject does nothing actively to minimize or maximize particle deposition in the lung. The International Commission On Radiological Protection (ICRP) models are examples of this. (See James A C, Stahlhofen W, Rudolph G, Egan M J, Nixon W, Gehr P, Briant J K, The respiratory tract deposition model proposed by the ICRP Task Group. Radiation Protection Dosimetry, 1991; vol. 38: pgs. 157-168).
[0169] However, in the field of aerosol drug delivery, a patient is directed to breathe in a way that maximizes deposition of the drug in the lung. This kind of breathing usually involves a full exhalation, followed by a deep inhalation sometimes at a prescribed inhalation flow rate range, e.g., about 10 to about 150 liters/minute, followed by a breath hold of several seconds. In addition, ideally, the aerosol is not uniformly distributed in the air being inhaled, but is loaded into the early part of the breath as a bolus of aerosol, followed by a volume of clean air so that the aerosol is drawn into the alveoli and flushed out of the conductive airways, bronchi and trachea by the volume of clean air that follows. A typical deep adult human breath has a volume of about 2 to 5 liters. In order to ensure consistent delivery in the whole population of adult patients, delivery of the drug bolus should be completed in the first 1-1½ liters or so of inhaled air.
[0170] As a result of the constraints of human inhalation drug delivery, a compound should be vaporized in a minimum amount of time, preferably no greater than 1 to 2 seconds. As discussed earlier, it is also advantageous, to keep the temperature of vaporization at a minimum. In order for a compound to be vaporized in 2 seconds or less and for the temperature to be kept at a minimum, rapid air movement, in the range of about 10 to about 120 liters/minute, should flow across the surface of the compound.
[0171] The following parameters are optimal in using a device of the present invention, due to human lung physiology, the physics of particle growth, and the physical chemistry of the desirable compounds:
(1) The compound should to be vaporized over approximately 1 to 2 seconds for creation of particles in the ultra fine range. (2) The compound should to be raised to the vaporization temperature as rapidly as possible. (3) The compound, once vaporized, should be cooled as quickly as possible. (4) The compound should be raised to the maximum temperature for a minimum duration of time to minimize decomposition. (5) The air or other gas should be moved rapidly across the surface of the compound to achieve the maximum rate of vaporization. (6) The heating of the air or other gas should be kept to a minimum, i.e., an increase of temperature of no greater than about 15° C. above ambient. (7) The compound should be mixed into the air or other gas at a consistent rate to have a consistent and repeatable particle size. (8) As the gas speed increases across the compound being vaporized, the cross sectional area through the device should decrease. Furthermore, as the surface area of the compound increases the heating of the gas increases.
[0180] The parameters of the design for one of the examples shown in FIGS. 2-5 , 7 and 8 are the result of meeting and balancing the competing requirements listed above. One especially important requirement for an aerosol containing particles with an MMAD between 10 nm and 100 nm is that a compound, while needing to be vaporized within at least a 1-second period, also needs to have each portion of the compound exposed to a heat-up period that is as brief as possible. In this example, the compound is deposited onto a foil substrate and an alternating magnetic field is swept along a foil substrate heating the substrate such that the compound is vaporized sequentially over no more than about a one second period of time. Because of the sweeping action of the magnetic field, each segment of the compound has a heat-up time that is much less than one second.
[0181] In the example noted directly above, the compound is laid down on a thin metallic foil. In one of the examples set forth below, stainless steel (alloy of 302, 304, or 316) was used in which the surface was treated to produce a rough texture. Other foil materials can be used, but it is important that the surface and texture of the material is such that it is “wetted” by the compound when the compound is in its liquid phase, otherwise it is possible for the liquid compound to “ball” up which would defeat the design of the device and significantly change the volatilizing parameters. If the liquid compound “balls” up, the compound can be blown into and picked up by the airflow without ever vaporizing. This leads to delivery of a particle size that is uncontrolled and undesirable.
[0182] Stainless steel has advantages over materials like aluminum because it has a lower thermal conductivity value, without an appreciable increase in thermal mass. Low thermal conductivity is helpful because heat generated by the process needs to remain in the immediate area of interest.
EXAMPLES
[0183] The following examples further illustrate the method and various examples of the present invention. These examples are for illustrative purposes and are not meant to limit the scope of the claims in any way.
Example 1
In Vivo Results Using Example 1
[0184] In this example, example 1, was designed to deliver an experimental dose of fentanyl between 20 μg and 500 μg, in a range of ultra fine particle sizes, in about 800 cc of air to a 10 kg dog. The lung volume of each dog under experimentation was approximately 600-700 cc and the device was designed to deliver the compound to the lung in the first half of the inhalation. Because of the value of these parameters, device 1 in this experiment can be considered a ¼ scale device for administering a dose to a human. It is believed that scaling the device to work for human subjects involves mainly increasing the airflow through the device. The time frame of the introduction of the compound into the heating/vaporization/mixing zone was set such that the compound vaporized into a volume of air that was suitable for both the volume required by dog lung anatomy (600-700 cc) and the volume needed to control the ratio of the compound to the air.
[0185] The following was the sequence of events that took place during each operation:
1. At the beginning of the run, the operator triggered inhalation controller 30 to start monitoring data from pressure transducer 240 and input flow meter 4 . 2. Controller 30 signaled controller 20 to start example 1 and to begin collecting data from the two temperature sensors and flow meter 4 . 3. After a pre-programmed delay, example 1 initiated the generation of the aerosol. (Note: there was a delay of about 0.4 seconds between the start of the controller 30 and the start of aerosol generation.) 4. After an independent preprogrammed delay (from original trigger signal), controller 30 opened input valve 58 to start forced inhalation to a dog under experimentation. 5. Example 1 completed the aerosol generation during the inhalation. 6. Controller 30 monitored flow meter 4 and pressure transducer 240 throughout the inhalation and closed off flow-at input valve 58 when a pre-specified volume or pressure was met. (Note: the pre-specified pressure is a safety feature to prevent injury to the subject animal. Termination of the breath at the pre-specified volume is the desirable occurrence of the experiment.) 7. After a breath hold delay (5 seconds), exhaust valve 40 was opened and the dog was allowed to exhale. 8. Exhaled aerosol was trapped on exhaust filter 40 for later analysis. Controller 30 recorded values for the following: volume dispensed, terminal pressure, duration of air pulse, and average flow rate. Controller 20 continuously recorded at millisecond resolution, input flow rate, exhaust flow rate, foil temperature, mouthpiece temperature, slide position, heater on/off time, and other internal diagnostic electrical parameters.
[0194] Three weight-matched female beagle dogs received fentanyl at a 100 μg intravenous bolus dose. The same dogs received fentanyl UF for Inhalation (100 μg aerosolized and administered as two successive activations of device 1 , containing approximately 50 μg fentanyl base) at a particle size of 80 nm (MMAD). The aerosol was administered to anesthetized dogs via the system schematically represented in FIG. 1 , with a target delivered volume of 600-700 ml air, followed by a 5 second breath hold. After dosing, plasma samples for pharmacokinetic analysis were obtained at various time points from 2 min to 24 hr. Fentanyl remaining in device 1 was recovered and measured. Fentanyl concentrations were measured by using a validated GC method, with a limit of detection of 0.2 ng/ml.
[0195] Plasma pharmacokinetics from this example were compared to intravenous (IV) fentanyl (100 μg) in the same dogs. Inhalation of fentanyl resulted in rapid absorption (C max ) maximum concentration in plasma, 11.6 ng/ml and T max , maximum time, 2 min.) and high bioavailability (84%). The time course of inhaled fentanyl was nearly identical to that of IV fentanyl. Thus, fentanyl UF for inhalation had an exposure profile that was similar to that of an IV injection.
[0196] Standard non-compartmental pharmacokinetic methods were used to calculate pharmacokinetic parameters for each animal. The maximum concentration in plasma (C max ) and the maximum time it occurred (T max ) were determined by examination of the data. The area under the plasma concentration vs. time curve (AUC) was determined. The bioavailability (F) of inhaled fentanyl was determined as:
[0000] F =( DIV/DINHAL )*( AUCINHAL/AUCIV )
[0197] where D was the dose and AUC was the AUC determined to the last measurable time point.
[0198] FIG. 26 plots the data obtained on the blood levels, by dog, for both the IV doses and the inhalation doses using device 1 as described above under Example 1.
[0199] The fentanyl aerosol was rapidly absorbed, with the same T max (2 min, the earliest time point) observed for both routes of administration. The maximum plasma concentration of fentanyl aerosol (11.6±1.9 ng/ml) was nearly two-thirds that of IV fentanyl (17.6±3.6 ng/ml). Plasma concentrations fell below the assay limit of quantitation by 6-8 hr after IV administration and by 3-4 hr after aerosol inhalation. Bioavailability calculations were based on the AUC's observed to the last measurable time point for the inhalation administration. Bioavailability for the inhalation study was 84% based on the nominal (uncorrected) fentanyl dose.
[0200] The mean plasma elimination half-life was similar after IV (75.4 min) and inhalation dose. Distribution phase half-lives (3-4 min) were also similar after both routes of administration. The inter-animal variability of pharmacokinetic parameters after the inhalation dose was low, with relative standard deviations (RSD<25%) lower than those observed for IV administration.
Example 2
In Vitro Results Using Example 1
[0201] Table 2 below summarizes the data collected from use of example 1 for in vitro testing of fentanyl. Particle size was measured with a Moudi cascade impactor.
[0000]
TABLE 2
Compound Mass (ug)
Mixing air volume (cc)
MMAD (nm)
GSD
20
400
71
1.9
25
400
72-78
1.7-1.8
50
400
77-88
1.7-185
100
400
100-105
1.4-1.8
200
400
103-123
1.6-1.9
300
400
140-160
1.8-2.1
Example 3
Use of Example 1 to Make Fine Aerosol Particles
[0202] In this example, example 1 was slightly modified and the flow rate changed, as discussed below, to make a fine aerosol in the 1 to 3 micron particle size range.
[0203] Airway section 140 was removed and the air channel heating/vaporization zone 70 was changed. An airway insert (not shown) had a “roof” that was 0.25 inches above the foil. There were no mixing rods as rapid mixing was not desirable in this example. Because of these two device changes, there was much less mixing with the air, thus the vapor/aerosol cloud was mixed with less air and produced a larger particle size aerosol. The airflow rate was reduced 1 liter/minute in this example. Again, this allowed the vapor to be mixed with much less air, resulting in the larger particle size aerosol.
[0204] Some operational problems with high compound loading on foil 64 in example 1 were encountered. The compound tested, dioctyl phthalate (DOP), was an oil and during the aerosolization process, a substantial quantity was blown downwind and not aerosolized. Three additional design alternatives were made to address this issue, involving changes to the substrate surface that the compound was deposited on. In the three alternatives, the substrate was made to “hold” the compound through the use of texture. They were: a) texturing the foil; b) adding a stainless steel screen on top of the foil; and, c) replacing the foil with a fine stainless steel screen.
[0205] The results from this example are set forth below in Table 3 below:
[0000]
TABLE 3
Substrate Type
MMAD, microns
GSD
Emitted Dose, ug
Textured foil
1.49 microns
1.9
97
Textured foil
2.70 microns
1.95
824
Fine screen alone
1.59 microns
1.8
441
Fine screen alone
1.66 microns
1.8
530
Screen on Foil
2.42 microns
2.2
482
[0206] As shown above, a fine particle size can be made with device 1 merely by changing the ratio of the compound to the mixing air.
Example 4
In Vitro Results Using Example 700
[0207] A tank was partially filled with DOP and placed inside an oven (not shown) having an inlet and an outlet. DOP was used as the test compound. The tank was purged with helium prior to heating the tank and its contents to a temperature of 350° C. Helium was pumped through the tank and used to carry the DOP vapor out of the outlet. The gaseous mixture of helium and vaporized compound 60 was introduced into different size mixing tubes through a nozzle. Each of the tubes had air moving through them at 14 liters/minute. The nozzle was perpendicular to the flow direction. After this gaseous mixture was mixed with the air, the resulting aerosol was introduced into a parallel flow diffusion battery for particle size analysis. Results are set forth in Table 4 below.
[0000]
TABLE 4
Mixing tube size (ID)
MMAD
GSD
4.8 mm
65 nm
1.3
14 mm
516 nm
3.3
[0208] As can be seen above, as the tube diameter became larger so did the particle size. Additionally, as the diameter became larger, the GSD also became larger. As the tube becomes larger, it is believed that the vaporized gas is introduced into a smaller segment of the mixing gas because the gas is being introduced as a point source leading to uneven mixing, which results in a large GSD.
Example 5
In Vitro Results Using Example 800
[0209] To demonstrate effectiveness of example 800, a 4-inch long piece of aluminum was fitted with a 150-watt cartridge heater at one end. The heater was powered with a variac AC power transformer. The thickness of the aluminum was designed to ensure that heat would transverse from one end of the aluminum to the other in approximately 30 seconds.
[0210] On the topside of the aluminum, an indentation was machined to hold the compound and to hold one of two top covers. The indentation for the compound was approximately 3.5 inches long and 0.4 inches wide. The indentation was 0.025 inches deep, and was filled with 1 mg of DOP.
[0211] The first top consisted of a sheet of flat glass placed 0.04 inches above the heated surface, creating an airway. At the exit end an outlet was fitted allowing the air to be drawn into an analytical measurement device. Air was made to flow through the airway at a rate of 15 liters/minute.
[0212] In the second configuration, the top was replaced with a half cylinder made of glass. This increased the cross sectional area of the airway by an order of magnitude.
[0213] Particle size was measured with both configurations and shown to be affected by the cross sectional area of the airway.
[0214] Results from the thermal gradient test are set forth in Table 5 below:
[0000]
TABLE 5
Cover size and
cross-section
MMAD
GSD
Small
92 nm
1.4
Big
650 nm
unknown
[0215] As shown above, the results confirm that as the cross section becomes larger, so does the particle size.
Example 6
In Vitro Results Using Example 900
[0216] In this example for producing aerosols, airway passage 910 was constructed from 18 mm diameter glass tubing. However, the passage can be made in any shape with a comparable cross-sectional area and out of any suitable material. The screen size, mesh, and the amount of compound were chosen in this example so that a gas could pass through the screen without interference once the compound had been deposited on it.
[0217] Because the internal resistance of the screen was low, i.e., between 0.01 and 0.2 ohms, the discharge rate (the RC time constant) of the capacitor was rapid, and on the order of a few milliseconds, i.e. less than 20 milliseconds, preferably in the range of about 2 to about 10 milliseconds. Upon discharge of capacitor 902 and the subsequent heating of screen 902 , the deposited compound was rapidly vaporized. Because air moved through screen 902 , the vaporized compound rapidly mixed with air and cooled.
[0218] The compound was deposited onto the fine stainless steel screen, e.g., 200 mesh, made from 316 stainless steel, having measurements of 2.54 cm.×2.54 cm. The current from the capacitor was passed between one edge and another. It was not necessary to heat the screen to temperatures comparable to the thin foil in Example 1, because the compound vaporized at a lower temperature due to the rapid air movement. Rapid air movement allowed the compound to vaporize at a lower vapor pressure, since airflow constantly removed compound vapors from the surface as soon as they were formed. Thus, the compound vaporized at a lower temperature without decomposition.
[0219] Deposition of the compound onto the screen was accomplished by mixing the compound with an organic solvent until the compound dissolved. The resulting solution was then applied to the fine stainless steel screen 902 and the solvent was allowed to evaporate. The screen was then inserted into holder 940 that electrically connected two sides of screen 902 to the power circuit described above.
[0220] A 10,000 mF capacitor was discharged while the gas was passing through screen 902 . The rapid heat up of the screen resulted in a rapid vaporization of the compound into the gas. Thus the resulting vaporized compound was mixed into a small volume of the gas. Because the ratio of the mass of the compound to the volume of the mixing gas was large, a fine (1-3 micron diameter) particle aerosol was made.
Example 7
General Procedure for Screening Drugs to Determine Aerosolization Preferability
[0221] Drug (1 mg) is dissolved or suspended in a minimal amount of solvent (e.g., dichloromethane or methanol). The solution or suspension is pipetted onto the middle portion of a 3 cm by 3 cm piece of aluminum foil. The coated foil is wrapped around the end of a 1½ cm diameter vial and secured with parafilm. A hot plate is preheated to approximately 300° C., and the vial is placed on it foil side down. The vial is left on the hotplate for 10 s after volatilization or decomposition has begun. After removal from the hotplate, the vial is allowed to cool to room temperature. The foil is removed, and the vial is extracted with dichloromethane followed by saturated aqueous NaHCO 3 . The organic and aqueous extracts are shaken together, separated, and the organic extract is dried over Na 2 SO 4 . An aliquot of the organic solution is removed and injected into a reverse-phase HPLC with detection by absorption of 225 nm light. A drug is preferred for aerosolization where the purity of the drug isolated by this method is greater than 85%. Such a drug has a decomposition index less than 0.15. The decomposition index is arrived at by subtracting the percent purity (i.e., 0.85) from 1.
[0222] One of ordinary skill in the art can combine the foregoing examples or make various other examples and aspects of the method and device of the present invention to adapt them to specific usages and conditions. As such, these changes and modifications are properly, equitably, and intended to be, within the full range of equivalents of the following claims. | The present invention relates to the inhalation delivery of aerosols containing small particles. Specifically, it relates to a device that forms drug containing aerosols for use in inhalation therapy. In a device aspect of the present invention, a device for delivering drug containing aerosols for inhalation therapy is provided. The device includes a housing and an airway that has a gas/vapor mixing airway. The airway further includes a subassembly, which has a metallic substrate coated on its surface with a composition comprising a drug. | 0 |
This invention relates to a process for making whiskers, fibers and flakes of transition metal compounds, in particular titanium nitride and chromium nitride, and was developed under United States Department of Energy contract number DE-ACO5-84OR21400.
BACKGROUND
Whiskers are single crystals that have a high length to width ratio. When incorporated into the matrix of materials such as ceramics, the result can be a composite having improved strength and toughness. A great deal of research is being done in this area to improve the performance of ceramics in applications such as cutting tools, turbine parts and internal combustion engine parts.
Whiskers made of titanium nitride are of interest since the compound has a high melting point of 2950° C., a hardness of 8-9 in Moh's scale, exhibits good electrical conductance and is stable at high temperatures in inert atmospheres. However, to date the processes for making TiN whiskers have almost exclusively required a gas phase reaction between TiCl 4 , N 2 and H 2 at temperatures above 1000° C., with the attendant problems of controlling the gas flow rate and the disposal of the HCl by-product. These processes are not only very expensive due to the extreme conditions required, but they also result in low product yields.
Only recently have alternative methods for TiN synthesis been reported. Three reactions that have been developed are molten cyanide with sodium-titanium bronze; oxide-containing molten alkali cyanide with TiN powder or TiO 2 ; and molten alkali cyanides with alkali titanates. These reactions take place in the liquid phase yielding a product of whose whisker morphology cannot always be consistently repeated. There is a need for a process that would yield a product having a morphology that can be anticipated and consistently repeated.
SUMMARY OF THE INVENTION
In view of the above stated needs, it is an object of this invention to provide a process for making whiskers, fibers and flakes of transition metal compounds that yields a product having a morphology that can be anticipated.
It is another object of this invention to provide a process for making transition metal compounds that provides a product that has the same shape as the starting material.
A further object of the invention is to provide a topochemical process for the formation of transition compounds shaped as whiskers, fibers and flakes.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the foregoing and other objects and in accordance with the purpose of the present invention, as embodied and broadly described herein, the process of this invention may comprise mixing a compound having particles of known morphology, said compound selected from the group consisting of potassium titanate and potassium chromate, with NH 3 at a temperature of about 1000° C. for from about 24 to about 72 hours resulting in the production of a nitride compound having particles in the same morphology as the starting material. The advantage of this invention is that one can begin with a starting material having particles of a known form and be assured that the morphology will remain in the final product.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The selection of the starting material for this process is a critical element of this invention. The examples presented here use whiskers and flakes (or platelets) as starting material, the choice depending on the form that is desired for the product. Since the reaction is topochemical, that is it starts on the surface of the solid, the shape of the particle is not disturbed from starting material to final product.
To obtain the starting material potassium titanate (K 2 Ti 6 O 13 , K 2 Ti 4 O 9 or K 2 Ti 6 O 5 ) in the form of whiskers a number of processes are available. One way is to melt TiO 2 and K 2 CO 3 (molecular ratio of 3:1) at 1000° C., cool quickly with water and then wash with water until the water is faintly alkaline. Another reaction is to heat TiO 2 and K 2 CO 3 (molecular ratio 5 or 6:1) to 1000° C., cool, grind and reheat several times. The resulting K 2 Ti 6 O 13 is then placed with an excess (about 1:10 by weight) of an about equimolar mixture of KF and KCl at 1200° C. for 30 to 60 minutes. After cooling slowly, the K-halides are extracted with hot water until there is no Cl-reaction with AgNO 3 solution. A variation of this reaction is to add TiO 2 and K 2 CO 3 to the KF-KCl mixture and heat at 1200° C. for 1 hour. Another variation is to add only TiO 2 to the KF-KCl mixture and let the air in the furnace provide the oxygen by means of the reaction
6TiO.sub.2 +2KCl+1/20.sub.2 →K.sub.2 Ti.sub.6 O.sub.13 +Cl.sub.2
The starting material K 2 Ti 6 O 13 is then reacted with NH 3 to produce TiN whiskers or fibers. Since the size and morphology of crystals grown from melts is relatively easy to control by methods known to persons of ordinary skill in the art, for instance by controlling the cooling rate, it follows that it should be easy to control the size and shape of the resulting TiN whiskers. It appears that a heterogeneous topochemical reaction occurs whereby, surprisingly, potassium is volatilized in some form, probably as KOH.
The above preparations of starting material were made in platinum containers and the resulting products were obtained as thick disks or cakes of whiskers. The cakes were scraped in water to suspend the whiskers which were then collected and compacted by filtration in dies of different shapes or as a wool like material. The chemical composition of K 2 Ti 6 O 13 was established by X-ray diffraction (XRD), its morphology observed by microphotography using a scanning electron microscope (SEM) and the whiskers were confirmed to be whiskers (single crystals) by electron diffraction (ED).
The composition and process described in the following example is intended to be illustrative and not in any way a limitation on the scope of the invention. Persons of ordinary skill in the art should be able to envision variations on the general principle of this invention that fall within the scope of the generic claims the follow.
EXAMPLE 1
Portions of starting material were contained in crucibles of different materials, such as Al 2 O 3 , Ni and graphite, which were placed in vertical nickel reactors attached to Pyrex tops. The latter had openings for a thermocouple well, gas inlet and outlet. The preferred crucible material is graphite or vitreous carbon. After displacing the air with N 2 or Ar, NH 3 either pure or diluted with those gases was flown through the system for different periods of time at various temperatures. From several experiments it was concluded that pure NH 3 , a reaction temperature of 1000° C. and a reaction time of 24 to 72 hours were the preferred parameters under the geometrical conditions of this rection. The configuration of the experiment does not appear to be important in regard to conversion; for a good rate of conversion, what is necessary is a good contact between the NH 3 and the K 2 Ti 6 O 13 . The techniques used to characterize the K 2 Ti 6 O 13 whiskers (XRD, SEM and ED) were employed to characterize the resulting TiN whiskers, and showed that the morphology had remained unchanged. Other experiments were performed in which a densely packed disk or cake of K 2 Ti 6 O 13 whiskers was converted in situ into a densely packed disk or cake of TiN whiskers.
EXAMPLE 2
Dark green platelets of Cr 2 O 3 were obtained by decomposition of K 2 CrO 4 at 900° C. The platelets were separated by filtration after dissolving the K 2 CrO 4 byproduct in water. Using the same experimental procedure as described in Example 1, about 0.5 g of the Cr 2 O 3 platelets were exposed to flowing NH 3 gas at 900° C. for a total of 60 hours. Metallic looking, shiny flakes were obtained; the measured weight loss of 13.23% agreed well with the value of 13.15% calculated for the conversion of CrO 1 .5 to CrN. X-ray diffraction confirmed that the flakes consisted of pure CrN. SEM of the flakes of Cr 2 O 3 and CrN showed that their morphology remained unchanged.
The subject invention can be used to prepare high quality transition metal nitride whiskers, flakes and fibers which may be useful for toughening ceramics and other appropriate matrices. Suggested uses of the invention are for valves that are exposed to slurries, for heat engines and prehaps as cutting tools. Ceramic composites are the subject of much industrial activity and it is expected that this invention will have application in that area of technology. | A process for making titanium and chromium nitrides of known morphology by reacting potassium titanate and chromium oxide in the gas phase with NH 3 . The products exhibit the same morphology as the starting material. | 2 |
FIELD OF THE DISCLOSURE
[0001] The present disclosure relates to a hand tool with a torque drive shaft and a housing equipped to house multiple work pieces, and more particularly, to a hand tool with a drive shaft capable of torque in a freewheeling position when an axial pressure force is placed along the drive shaft, and manual removal from the housing for use of the drive shaft as a tool.
BACKGROUND
[0002] Hand tools are used to assemble, repair, service, or build different mechanical equipment. Tools are used in the home and workshop for a wide range of applications, including the assembly of furniture, repairing a ventilation grate, fixing a door or window, etc. Tools are also used in commercial settings by service providers, including installing cable service, repairing a vehicle, working in a shop, etc. Hand tools such as screwdrivers, wrenches, hammers, and crowbars are designed for manual use by an individual and must have a controlled weight and size that allow repetitive use without undue fatigue. Hand tools are used to deliver targeted forces such as blunt forces, torques, and punctures upon different materials. For example, a screwdriver must transfer a torque created from the wrist of an individual onto a screw that must be removed or inserted.
[0003] Efficient hand tools allow for targeted use of manual force upon a point of use to limit muscle fatigue of a user. One way to limit muscle fatigue is by reducing the weight of the hand tool, often making the tool more brittle and prone to damage. Another way to limit fatigue is to better anticipate and optimize the multiple steps needed to perform a task. When inserted or removed, screws need a high degree of torque but low rotational movement at positions where the screw is gripped, stuck, or must deform the greatest amount of matter to push in. Screws also need low torque but high rotational movement at a position where the screw moves almost freely along filets. A user ends up wasting valuable time and energy by moving the totality of a conventional tool during removal of a screw when such movement is not truly required. What is needed is a hand tool capable of transfering high torque when needed but also low torque without having to move the weight of the hand tool.
[0004] Another known problem with hand tools is their incapacity to utilize the human hand in which they are placed. The human hand has a metacarpus (a broad inside palm) attached to the carpus (the wrist) capable of delivering strong torque to hand tools placed within the curve of a hand. The hand is also equipped with four fingers placed in opposition via the trapedium to a thumb capable of very high tactile dexterity and perform precise actions using a hand tool placed in proximity with the ends of the fingers and thumb. Currently, hand tools fail to utilize the combination of force of the bottom section of the hand and the dexterity of the upper section of the hand when conducting a single operation. For example, screwdriver users hold a tool in their palm and must transfer the hand tool out of the hand to use the tip of the fingers to feel the precision of the screw position on a surface during the final stages of insertion. What is needed is a hand tool capable of utilizing the unique capacity of the finger tips and the thumb while at the same time utilizing the strength of the palm of a hand.
[0005] Tool users may also work remotely from a ledge or a flat surface where tools can be put down between successive uses. Some tool users equip themselves with toolbelts or wrist bands to store the tool between uses. Again, energy is lost by having to remove the hand tool from the hand and having to place it back the hand when needed. The adult human hand is capable of numerous types of grips. Dentists and surgeons, for example, distinguish among the different types of grips. The adult human hand is dextrous enough to transfer a hand tool used in a pen grasp (between the tips of the fingers) to a palm grasp (between the palm and the bottom of the small finger) and so forth without the need of a second hand. A hand tool capable of being handled with a finger grip and a palm grip should also be capable of temporary storage within the hand while a user requires the use of his four fingers and thumb. What is needed is a hand tool capable of utilizing this unique capacity of the adult human in conjunction with the other advantages given above to save energy by reducing the displacements required to operate a hand tool.
SUMMARY
[0006] The present disclosure relates to a hand-held tool that may be held in the palm of a hand, the hand-held tool being of adequate length and size to allow users to comfortably transfer the tool from a palm grip to a pen grip to maintain the use of the fingers and the thumb when the hand tool is stored in the palm. One or several storage housings are attached offset from a drive shaft housing for improved torque transfer from a hand to the tool head, integral storage of work pieces, optimized use of palm torque during use, and better overall grasping. The hand tool is also equipped with a retractable or nonretractable torque drive shaft designed to allow the fingers and thumb of a user to be rotated freely when the tool is in palm grip and capable of transmitting torque through the housing when an axial pressure force is placed along the drive shaft to engage the tool head with the housing. The drive shaft can also be reversed to create a prolongation shaft or placed in another opening of the housing. In yet another embodiment, a flexible shaft or a telescopic shaft can be used as a drive shaft to reach remote or offset locations. In another embodiment, a biasing element can be used as a grip to activate the drive shaft. In another embodiment, the drive shaft can be dissociated from the housing and used independently. Finally, in another embodiment, the drive shaft can be forced into a torque drive mode by locking the drive shaft into the housing or a holster while the hand tool is used.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a perspective view of the hand tool with torque drive shaft where the biasing force made by the housing according to a first embodiment of the present disclosure.
[0008] FIG. 2 is an exploded perspective view of the hand tool with torque drive shaft as shown in FIG. 1 .
[0009] FIG. 3 is a side view of the hand tool with torque drive shaft as shown in FIG. 1 .
[0010] FIG. 4 is a perspective partial cross-sectional view of the hand tool with torque drive shaft as shown in FIG. 1 in a first disengaged operative position.
[0011] FIG. 5 is a side cross-sectional view of the hand tool with torque drive shaft as shown in FIG. 1 in a second engaged operative position.
[0012] FIG. 6 is a side elevation view of the hand tool with torque drive shaft as shown in FIG. 1 with an alternate orientation and alternate torque drive shafts according to other possible embodiments.
[0013] FIG. 7 is a side elevation view of the hand tool with torque drive shaft as shown in one of the alternate embodiments of FIG. 6 equipped with the extracted shaft.
[0014] FIG. 8 is a side elevation view of the hand tool with torque drive shaft as shown in one of the alternate embodiments of FIG. 6 equipped with the telescoping shaft.
[0015] FIG. 9 is a side elevation view of the hand tool with torque drive shaft as shown in one of the alternate embodiments of FIG. 6 equipped with the flexible shaft.
[0016] FIG. 10 is a close-up diagrammatic view of the engagement mechanism between a first coupling element and a second coupling element in a disengaged configuration.
[0017] FIG. 11 is a close-up fractional sectional view of the engagement mechanism as shown in FIG. 10 in the engaged configuration.
[0018] FIG. 12 is a detailed cut-away view of the head portion of the hand tool with insert and a segmented lip as shown in FIG. 1 .
[0019] FIG. 13 is a detailed cut-away view of the head portion of the hand tool as shown in FIG. 12 without the insert.
[0020] FIG. 14 is a detailed cut-away view of the head portion of the hand tool with torque drive shaft where the biasing force is made by the actuator without the insert according to another embodiment of the present disclosure.
[0021] FIG. 15 is a perspective view of the hand tool without the insert as shown in FIG. 14 .
[0022] FIG. 16 is a side elevation view of the hand tool of FIG. 14 with a work piece in alignment to impart work to a work piece.
[0023] FIG. 17 is a detailed cut-away view of the hand tool of FIG. 14 in a first operating position.
[0024] FIG. 18 is a detailed cut-away view of the hand tool of FIG. 14 in a second operating position.
[0025] FIG. 19 is detailed a cut-away view of the head portion and actuator of the hand tool with torque drive shaft where the biasing force is made by a spring on the actuator with insert according to another embodiment of the present disclosure.
[0026] FIG. 20 is an exploded perspective view of the hand tool of FIG. 19 without the driving shaft.
[0027] FIG. 21 is a side election view of the hand tool of FIG. 19 with work piece.
[0028] FIG. 22 is a partial cross-sectional view of the hand tool of FIG. 19 in a first operative position.
[0029] FIG. 23 is detailed partial cross-sectional view of the hand tool of FIG. 19 in a second operative position.
[0030] FIG. 24 is a detailed cut-away view of the hand tool with torque drive shaft with pivoting head in closed configuration according to another embodiment of the present disclosure.
[0031] FIG. 25 is an exploded perspective view of the hand tool of FIG. 24 with the torque drive shaft pivoted at a 90° angle in a semi-opened configuration.
[0032] FIG. 26 is a partial cut-away view of the hand tool of FIG. 24 in the semi-opened configuration in a first operative position.
[0033] FIG. 27 is a partial cut-away view of the hand tool of FIG. 24 in the semi-opened configuration in a second operative position.
[0034] FIG. 28 is a perspective view of the hand tool with torque drive shaft where a manual biasing force is required on the driving shaft according to another embodiment of the present disclosure.
[0035] FIG. 29 is an exploded perspective view of the hand tool of FIG. 28 .
[0036] FIG. 30 is a side elevation view of the hand tool of FIG. 28 in a first operative position.
[0037] FIG. 31 is a partial cut-away view of the hand tool of FIG. 28 in the first operative position.
[0038] FIG. 32 is a partial cut-away view of the hand tool of FIG. 28 in the second operative position.
[0039] FIG. 33 is a perspective view of the hand tool shown in FIG. 1 with a double storage element compartment according to another possible embodiment of the present disclosure.
[0040] FIG. 34 is a perspective view of the hand tool shown in FIG. 1 with a quadruple storage element compartment according to another possible embodiment of the present disclosure.
DETAILED DESCRIPTION
[0041] FIGS. 1-34 illustrate seven of the numerous possible embodiments of hand tool 1 shown in this disclosure when the teachings taught hereafter are embodied in a handful of embodiments. For each of the disclosed embodiments, what is contemplated is the use of a drive assembly 2 having a drive shaft 13 capable of rotation and insertion on an opposing end or at a different location in a housing 3 . FIGS. 1-13 show a hand tool 1 with a torque drive shaft, also known as a drive assembly 2 , with a housing 3 with a first type of actuator 14 that slides into the housing 3 from a second engaged operating position shown in FIG. 5 to a first disengaged operating position shown in FIG. 4 . The drive assembly 2 is biased outwards from the housing 2 to a freewheeling mode associated with the first operating position by a biasing force made by the housing upon the actuator 14 .
[0042] FIGS. 14-18 show another embodiment of the hand tool 1 according to a second embodiment where the actuator 14 slides over part of the housing 3 to move the drive assembly 2 from a second engaged operating position shown in FIG. 18 to a first disengaged operating position shown in FIG. 17 . The drive assembly 2 is biased outward from the housing 2 to a freewheeling mode associated with the first operating position by a biasing force made by the actuator 14 upon the housing 3 .
[0043] FIGS. 19-23 show another embodiment of the hand tool 1 according to a third embodiment where the actuator 14 slides over directly against the housing 3 to move the drive assembly 2 from a second engaged operating position shown in FIG. 23 to a first disengaged operating position shown in FIG. 22 . The drive assembly 2 is biased outward from the housing 2 to a freewheeling mode associated with the first operating position by a biasing force made by a spring 34 acting against the actuator 14 and the housing 3 .
[0044] FIGS. 24-27 show yet another embodiment of the hand tool 1 according to a fourth embodiment where the drive assembly is freestanding and the biasing force is made by an inner spring 34 to move the drive assembly 2 from a second engaged operating position shown in FIG. 27 to a first disengaged operating position shown in FIG. 26 . The embodiment shown in FIGS. 24-27 is also capable of operation in the second engaged operation when the hand tool 1 is in closed position as shown on FIG. 24 in a holster (not shown).
[0045] FIGS. 28-32 show yet another further embodiment of the hand tool 1 according to a fifth embodiment where the biasing force to disengage the drive assembly 2 from a second engaged operating position shown in FIG. 32 to a first disengaged operating position shown in FIG. 31 is made manually. The force to engage the drive assembly 2 from the first operating position to a second operating position corresponds to the axial push force placed upon a work element 101 when a user desires to engage the hand tool 1 and transfer torque to a work piece 22 and ultimately to the work element 101 .
[0046] What is shown in FIG. 1 is a hand-held tool 1 with a generally cuboid-shaped housing 3 with a protuberance 100 offset from the main axis formed by the drive assembly 2 . In this embodiment, a user places the protuberance 100 in the palm of the hand. A storage element compartment 9 or any other offset volume is then gripped between the palm and the four fingers with the head portion 5 placed next to the index finger in an upright position. A work piece 22 is then inserted into the first receptacle 70 if the hand tool 1 is used as a tool to transfer force to an element such as a screw 102 fixed at a location, such as a work element 101 as shown in FIGS. 7-9 .
[0047] By way of example, FIG. 16 shows one embodiment where a work piece 22 is used to connect with a fastener 103 on a work element 101 . One of ordinary skill in the art understands that what is also contemplated is the use of any other possible work piece 22 that may be used in association with the hand tool 1 , or configurations where a work piece 22 is formed as an integral part of the drive shaft 13 , or even tools where the fastener 103 or any mechanical element can be inserted directly within the first receptacle 70 on the drive shaft 13 or any other such functional uses to enable a work piece 22 to conduct work on a surface. In one embodiment as shown in FIG. 16 , the fastener 103 is a bolt.
[0048] FIG. 2 is an exploded view of one possible embodiment the hand tool 1 where a series of work pieces 22 are stacked vertically within the storage element compartment 9 and covered with a protector 104 made to confine the work pieces 22 within the storage element compartment 9 . The protector 104 also includes a series of external ridges 105 in contact with the hand of a user to increase the gripping efficacy of the hand tool 1 . The hand tool 1 is ergonomically designed to be held by a user and is made of any suitable material capable of withstanding the different internal and external shear forces and constraints commonly associated with a hand tool 1 . In one possible embodiment, the housing 3 and the protector 104 are made of a nondeformable polymer, a shape-retaining material, and/or high-resistance polymer blend while the other components are made of steel, metal, ceramic, composite, or natural ceramic mesh compound such as Kevlar. What is also disclosed and contemplated is the use of any suitable material recognized by one of ordinary skill in the art of such design thickness in relevant bending sections to allow for sections to be carved out and rotated around a fixed point without permanent deformation to create elements capable of producing a biasing force between different elements of the hand tool 1 at appropriate locations.
[0049] The work piece 22 in one embodiment is located at the end of the drive assembly 2 , and more precisely, at the end of the drive shaft 13 . The user operates either an actuator 14 or the drive shaft 13 directly when no actuator 14 is available when the drive shaft 13 is in the first operative position or the freewheeling mode. In one preferred embodiment, the user rotates the actuator 14 using the thumb and the index finger or the middle finger while holding the housing 3 with the ring finger and the little finger against the palm of the hand. What is disclosed is only one of a plurality of possible hand and finger placements, given as a nonlimiting example to understand how the freewheeling mode is operated by a user. While one possible mode of operation is disclosed, what is contemplated is the use of the hand tool 1 by a user in association with any part of the hand or with other tools. Figures show the actuator 14 or other external parts of the hand tool 1 with surface notches 106 or other type of surface irregularities designed in part to increase the fiction between the actuator 14 and an operating finger, limit rotational movements, and/or increase the overall aesthetics of the hand tool. In one embodiment, the drive shaft 13 is movably rotated by using an external surface of the biasing element located on the drive shaft 13 . As a nonlimiting example, if a small O-ring is used as a biasing element where the surface of the O-ring is compressed between the actuator 14 and the housing 3 , the middle section of the O-ring located between both surfaces of compression can be made accessible to the user of the hand tool 1 for rotation of the drive shaft in the disengaged operating position.
[0050] The hand tool 1 includes a housing 3 as shown in the exploded perspective view of FIG. 2 . The housing 3 includes a bore 4 defined therein, a first end 6 of the housing 3 defining a first coupling element 7 that may be disposed on an inner surface 8 or disposed about the bore 4 , and a storage element compartment 9 made of a plurality of walls 10 contiguous with the housing 3 to define a cavity 11 and an opening 12 . The bore 4 is shown in FIGS. 2 and 4 . The bore 4 as shown in one embodiment is cylindrical in shape, with a constant longitudinal diameter slightly greater than the external diameter of the drive shaft 13 to be inserted fully or partly therein. In one embodiment, the bore 4 is made throughout the housing 3 , but what is contemplated is the use of a bore 4 of sufficient geometry, size, and length to accommodate the drive shaft 13 and allow for the engaging mechanism of the drive assembly 2 to operate. By way of nonlimiting example, the use of a bore 4 of sufficient size and length could lead to additional storage space for additional work pieces 22 within the drive shaft 13 or the housing 3 . FIGS. 33-34 show a configuration where the housing 3 comprises additional storage space for additional work pieces 22 . What is also contemplated is a bore 4 that does not traverse the housing 3 and leaves an end plate (not shown) where a biasing element such as a spring 34 may be housed to create a biasing force between the end plate (not shown) and the drive shaft 13 to return an engaged drive assembly 2 to the freewheeling mode.
[0051] The head portion 5 is shown in FIG. 1 with a slightly greater diameter than the protuberance 100 to maintain a mechanical resistance of the housing in light of the insert 35 placed at the first end 6 . The head portion 5 is located at the first end 6 of the housing 3 . While it is understood by one of ordinary skill in the art that the housing is designed to have a minimum weight and volume, any ergonomic design or other housing design to be placed in a hand is also contemplated and acceptable. While a protector 104 with ridges 105 is shown, what is contemplated is any storage system, including but not limited to a bottom or side sliding mechanism with or without biasing elements, the placement on the housing 3 of magnets or sliding elements where a module can be slid in place, and the like.
[0052] The drive assembly 2 with a drive shaft 13 is removably disposed at least partially within the bore 4 . An actuator 14 disposed on the drive shaft 13 and a biasing mechanism or a manual biasing force is used for generating a biasing force that acts on the actuator 14 and the housing 3 so that the drive shaft 13 is normally disposed in a first disengaged operative position and pushed into the second engaged operative position. What is shown and contemplated is the use of any type of mechanism that allows the drive shaft 13 , with or without an actuator 14 , to slide a short distance into the housing with an axial force to enable a mechanical lock between the housing and the drive shaft 13 and induce a biasing force capable of sliding the drive shaft 13 out of the housing 3 in an unlocked configuration. In one embodiment, the drive shaft 13 is slid approximately 1 mm into the housing. One of ordinary skill in the art recognizes that a wide range of biasing elements, including but not limited to magnets, springs, plates, liquids, elastomeric bands, O-rings, rings, and the like, can be used to bias the drive shaft 13 and the housing 3 to unlock the two elements once the torque force associated with an axial drive force is no longer present on the drive shaft 13 . One of ordinary skill in the art also recognizes that a biasing element with a built-in capacity to create a force in opposition to any deformation, such as a flexible collar, a polymer, an elastomer band, or materials with a memory, may be used to control the axial deformation from the first operating position to the second operating position and back from the second operating position to the first operating position.
[0053] In other embodiments, the hand tool 1 includes an actuator 14 integrally formed on the drive shaft 13 or coupled to the drive shaft 13 . FIG. 2 shows one possible type of coupling of the actuator 14 on the drive shaft 13 using a raised section 36 locked in place by two clips 37 on each side of the actuator 14 . While one possible mode of assembly is shown, what is contemplated is any type of assembly, including but not limited to a drive shaft 13 with an integral built-in actuator 14 . In one preferred embodiment, a crenellated surface on the drive shaft 13 is used. The drive shaft 13 includes a first end portion 15 having a first receptacle 70 designed to accommodate a work piece 22 . The drive shaft 13 also includes in one embodiment a second end portion 16 with a second receptacle 21 (not shown in FIG. 2 but symmetrical to the first receptacle 70 as shown). The intermediate portion 17 of the drive shaft 13 is shown as being located between the first end portion 15 and the second end portion 16 . In one embodiment as shown in FIG. 2 , the first end portion 15 has a first longitudinal length 18 that is less than a second longitudinal length 19 of the second end portion 16 . The drive shaft 13 with different longitudinal lengths 18 , 19 can be removed and turned as shown in FIG. 6 , or other secondary lengths of flexible shaft 120 can be used as shown in FIG. 6 , such as other telescopic lengths or flexible lengths with male 121 and female 122 connectors. These shafts can also be made flexible 50 as shown in FIG. 9 , or telescopically extendable 51 as shown in FIG. 8 . FIG. 6 illustrates three different drive shaft 13 configurations in a side-by-side comparison. What is also contemplated is the use of any type and geometry of drive shaft 13 , including but not limited to an L-shaped drive shaft 13 and the like.
[0054] The intermediate portion 17 includes a second coupling element 20 complementary to the first coupling element 7 . The actuator 14 is movable with respect to the housing 3 when the drive shaft 13 is disposed in the first operative position. FIG. 4 shows the drive shaft 13 in the first operative position where the second coupling element 20 is not engaged with the first coupling element 7 . FIG. 5 shows the drive shaft 13 in the second operative position where the second coupling element 20 is engaged with the first coupling element 7 . The drive shaft 13 is also movable from the first operative position to a second operative position when the biasing force between the housing 3 and the driving assembly 2 is overcome. In one embodiment, the biasing force needed to move the drive shaft 13 from the first operative position to the second operative position corresponds to a small push from the hand or a force of less than 1 pound. What is shown in FIGS. 1-5 is a housing 3 capable of impermanent deformation to create a biasing force upon the actuator 14 .
[0055] FIG. 2 shows an actuator 14 immovable with respect to the housing 3 when the drive shaft is disposed in the second operative position as shown in FIG. 5 . The first coupling element 7 and the second coupling element 20 are engaged in the second operating position such that movement of the housing 3 translates into movement of the drive shaft 13 . FIG. 10 illustrates the interlocking of one possible geometry of first coupling element 7 to a complimentary geometry of the second coupling element 20 in a first position, and FIG. 11 shows the first coupling element 7 and the second coupling element 20 in the second operating position. One of ordinary skill in the art recognizes that while a series of parallel teeth are shown as geometries of the first coupling element 7 and the second coupling element 20 , what is contemplated is the use of any type of first coupling element capable of interlocking, sliding, attaching, or contacting with a second coupling element to transfer a torque placed upon the housing 3 to the drive shaft 13 on which the second coupling element 20 is placed 38 as shown in FIG. 11 .
[0056] FIG. 12 shows an embodiment where the biasing mechanism has a lip 23 defined on a distal end 60 of the head portion 5 having an inner edge 61 that defines a socket diameter 25 . The lip 23 includes a plurality of circumferentially spaced segments 24 . One of ordinary skill in the art recognizes that segments 24 are shown illustratively as one possible way to create a localized weakness in the lip 23 to allow for impermanent deformation of the lip 23 when in contact with a force to move the drive shaft 13 from a first operating position to the second operating position that requires the lip to move as shown by the arrows in FIG. 5 . In one preferred embodiment, the lip 23 is crenellated.
[0057] In one embodiment shown in FIG. 4 , the actuator 14 also has an outer surface 26 that defines an actuator diameter 27 that is not less than the socket diameter 25 such that the biasing force generated opposes movement of the drive shaft 13 from the first operative position as shown in FIG. 4 to the second operative position as shown in FIG. 5 . In one embodiment, the actuator includes a ridge 90 disposed on the outer surface of the actuator 14 for registration between adjacent segments 91 when the drive shaft 13 is disposed in the second operative position as shown in FIG. 11 .
[0058] FIGS. 14-18 show a biasing mechanism with a rim 28 defined on the actuator 14 including an inner edge 29 that defines a rim diameter 30 . The rim 28 as shown in FIG. 17 defines a plurality of circumferentially spaced segments 31 . The head portion 5 on the housing 3 has a distal end 32 that defines a head diameter 33 that is not less than the rim diameter 30 such that the biasing force generated opposes movement of the drive shaft 13 from the first operative position to the second operative position as shown in FIGS. 17 and 18 , respectively. In one embodiment, the biasing mechanism is a spring 34 as shown in FIG. 19 disposed between the first end 6 of the housing 3 and the actuator 14 such that the biasing force generated opposes movement of the drive shaft 13 from the first operative position to the second operative position. In one embodiment shown in FIG. 12 , the inner surface 8 is defined on an insert 35 secured to the first end 6 of the housing 3 . FIG. 13 shows an embodiment where the inner surface 8 is defined on the first end 6 of the housing 3 .
[0059] In another embodiment, the hand tool 1 includes a housing 3 having a bore 4 defined therein, a storage element compartment 9 with a plurality of walls 10 contiguous with the housing to define a cavity 11 , and an opening 12 . The drive shaft 13 is removably disposed at least partially within the bore 4 with an actuator 14 on the drive shaft 13 . What is also contemplated is the use of a drive shaft 13 with symmetrical ends that may be inserted in another opening made in the housing 3 or where the other end of the drive shaft 13 is inserted alternatively. The drive shaft 13 can be operated when functionally coupled with the housing 3 by moving the housing 3 or when in the second operating position can be operated by fingers of one hand. What is also contemplated is the use of hand actuation to translate the drive shaft 13 from a first operating position to a second operating position and from the second operating position back to the first operating position. The actuator 14 is also integrally formed on the drive shaft 13 , and the actuator 14 is coupled to the drive shaft 13 and includes a first end portion 15 with a first receptacle 70 , a second end portion 16 with a second receptacle 21 (not shown in FIG. 2 but symmetrical to the first receptacle 70 ), and an intermediate portion 17 disposed between the first end portion 15 and the second end portion 16 . In one embodiment, the first end portion 15 has a first longitudinal length 18 less than a second longitudinal length 19 of the second end portion 16 . The first coupling element 7 is defined about the bore 4 on an inner surface 8 and a second coupling element 20 is defined on the intermediate portion 17 that is complementary to the first coupling element 7 as shown in FIG. 2 .
[0060] In another embodiment, the drive shaft 13 is movable with respect to the housing 3 in a first operative position as shown in FIG. 4 defined when the first coupling element 7 is disengaged from the second coupling element 20 . In yet another embodiment, a movement of the housing 3 associated with torque to be transmitted by the hand tool 1 to the work element 101 translates into movement of the drive shaft 13 in a second operative position as shown in FIG. 5 when the first coupling element 7 is engaged with the second coupling element 20 .
[0061] What is also claimed is a method of imparting work to a work piece according to another embodiment of the present invention. The method includes the steps of providing a hand tool 1 including a housing 3 and a drive shaft 13 disposed at least partially within the housing 3 and movable with respect thereto, engaging a work piece 22 to the drive shaft 13 , and actuating the drive shaft 13 when disposed in the first operative position to impart work to the work piece 22 . The method in another embodiment comprises the step of having a second coupling element 20 complementary to the first coupling element 7 such that the drive shaft 13 is disposed in a first operative position as shown in FIG. 4 when the first coupling element 7 is disengaged from the second coupling element 20 and a second operative position as shown in FIG. 5 when the first coupling element 7 is engages the second coupling element 20 .
[0062] The method further includes the step of fitting a work element or work piece 22 adapted to engage the work piece 22 to the drive shaft 13 . Finally, the method also includes the further steps of engaging the work element 101 when the drive shaft 13 is in the first operative position, actuating the hand tool 1 such that the drive shaft 13 is disposed in the second operative position to impart work to the work element 101 .
[0063] In another embodiment shown in FIGS. 24-27 , the hand tool 1 includes a housing 3 having a first end 6 of the housing 3 , a drive assembly 2 with a drive shaft 13 movably connected to the first end 6 of the housing 3 , and a biasing mechanism 72 for generating a biasing force located between a first end portion 15 of the drive shaft 13 and a first end 6 of the housing 3 . The hand tool 1 also includes a storage element compartment 9 defined by a plurality of walls 10 contiguous with the housing 3 to define a cavity 11 and an opening 12 . What is shown is a first end portion 15 with a first receptacle 70 and a first end 6 that includes a hub 75 to facilitate pivotal connection to the second end portion 16 .
[0064] The hand tool 1 further comprises a lock mechanism 73 disposed on the first end 6 for selectively fixing the drive shaft 13 in a desired orientation as shown in FIG. 25 , namely, a 90° orientation with respect to the storage element compartment 9 . The lock mechanism 73 also includes a movable lock element 74 configured to engage the hub 75 on the housing 3 . The hub 75 facilitates pivotal connection to the first end 6 of the housing 3 , and the hub 75 includes a plurality of circumferentially spaced receptacles 76 . In another embodiment (not shown), the hub 75 includes a plurality of circumferentially spaced projections (not shown). One of ordinary skill in the art understands that while a hub 75 with receptacles 76 is shown, the counterpart where the lock element 74 includes receptacles is also contemplated and disclosed.
[0065] In one instance, the lock element 74 is pivotally connected to the first end 6 of the housing and the lock element 74 includes a protrusion 77 configured to engage at least one of the receptacles 76 . In another embodiment, the lock element 74 includes a recess (not shown) configured to engage at least one of the projections contemplated. The biasing mechanism in one embodiment shown in FIG. 25 includes a spring 72 . FIG. 26 shows a configuration where the first end portion 15 is movable with respect to the first end 6 when the drive shaft 13 is disposed in a first operative position. FIG. 26 illustrates the drive shaft 13 in the first operative position, and FIG. 26 illustrates the drive shaft 13 in the second operative position.
[0066] In another configuration, the second end portion 16 is secured in registration with the first end 6 when the drive shaft 13 is disposed in a second operative position as shown in FIG. 27 . The second end portion 16 includes an inner end having a second coupling element 20 , and the head includes a first coupling element 7 that is complementary to the second coupling element 20 . The housing 3 further comprises a holster 77 for receiving the drive shaft 13 . What is also shown is a drive shaft 13 that is rotated using an external surface of the biasing element 34 as explained herebefore. The holster 77 also includes a lip (not shown) for holding the driving shaft 13 in the second operating position along a closed position along the housing as illustrated in FIG. 24 . The hand tool 1 is usable in the closed position shown on FIG. 24 in the second operating position by rotating the hand tool 1 . In yet another embodiment, the drive assembly 2 can be disassociated from the housing 3 by a user and used a second tool.
[0067] What is also claimed is a method of imparting work to a work piece according to the embodiment shown in FIG. 24 . The method includes the steps of providing a hand tool 1 including a housing 3 having a movably connected drive shaft, the drive shaft 13 engaging a work piece 22 to the drive shaft 13 , and actuating the drive shaft 13 when disposed in the first operative position to impart work to the work piece 22 . The method in another embodiment comprises the step of having a second coupling element 20 complementary to the first coupling element 7 such that the drive shaft 13 is disposed in a first operative position when the first coupling element 7 is disengaged from the second coupling element 20 and a second operative position when the first coupling element 7 is engages the second coupling element 20 .
[0068] The method further includes the step of fitting a work element or work piece 22 adapted to engage the work piece 22 to the drive shaft 13 . Finally, the method also includes the further steps of engaging the work element 101 when the drive shaft 13 is in the first operative position and actuating the hand tool 1 such that the drive shaft 13 is disposed in the second operative position to impart work to the work element 101 . What is also contemplated is the additional step to this or the above disclosed method of engaging the work element 101 when the drive shaft 13 is in the third operative position and actuating the housing 3 when the drive shaft 13 is disposed this third operative position as shown on FIG. 24 to impart work to the work piece.
[0069] It is understood by one of ordinary skill in the art that these steps correspond to the general steps to be taken to practice the methods of this disclosure. Other auxiliary steps may be taken but do not affect the validity and completeness of the disclosure of this general method. Persons of ordinary skill in the art appreciate that although the teachings of the disclosure have been illustrated in connection with certain embodiments and methods, there is no intent to limit the invention to such embodiments and methods. On the contrary, the intention of this application is to cover all modifications and embodiments falling fairly within the scope of the teachings of the disclosure. | The present disclosure relates to a hand-held tool that may be held in the palm of a hand, the hand-held tool being of adequate length and size to allow users to comfortably transfer the tool from a palm grip to a pen grip to maintain the use of the fingers and the thumb when the hand tool is stored in the palm. One or several storage housings are attached offset from a drive shaft housing for improved torque transfer from a hand to the tool head, integral storage of work pieces, optimized use of palm torque during use, and better overall grasping. The hand tool is also equipped with a retractable or nonretractable torque drive shaft designed to allow the fingers and thumb of a user to be rotated freely when the tool is in palm grip and capable of transmitting torque through the housing when an axial pressure force is placed along the drive shaft to engage the tool head with the housing. The drive shaft can also be reversed to create a prolongation shaft or placed in another opening of the housing. In yet another embodiment, a flexible shaft or a telescopic shaft can be used as a drive shaft to reach remote or offset locations. In another embodiment, a biasing element can be used as a grip to activate the drive shaft. In another embodiment, the drive shaft can be dissociated from the housing and used independently. Finally, in another embodiment, the drive shaft can be forced into a torque drive mode by locking the drive shaft into the housing or a holster while the hand tool is used. | 1 |
BACKGROUND SECTION OF THE INVENTION
[0001] Light Emitting Diodes (“LED”) have become increasingly popular due to their low electricity usage, Light Emitting Diodes have begun replacing fluorescent lights in light fixtures.
[0002] A problem that exists with LED lights, particularly those that hang from a ceiling, is that they are not easy to maintain. A technician may have to take off the entire light fixture to service the fixture.
[0003] There is a need in the art to allow an easy to maintain LED light fixture that hangs from a ceiling while at the same time providing good lighting, heat dissipation, and be suitable for a manufacturing process on an industrial scale.
SUMMARY SECTION OF THE INVENTION
[0004] Provided is a light fixture comprising: a) a body for attaching one or more ballast; b) a bracket having a first and a second end that is pivotally attached at the first end to the body; and c) a reflector for placement of one or more LED (light emitting diode) strips attached to the bracket. The fixture can further comprise a door with a lens pivotally attached to the body, wherein the ballast is accessed by pivoting the reflector and the door in opposite directions.
[0005] Provided is a light fixture comprising: a) a body for attaching one or more ballast; b) a bracket having a first and a second end that is pivotally attached at the first end to the body; c) a reflector for placement of one or more LED (light emitting diode) strips attached to the bracket; d) a door with a lens pivotally attached to the body; wherein the ballast can be accessed by pivoting the reflector and the door in opposite directions. The reflector can be a flat reflector. The reflector can have cavities formed by protrusions for placement of multiple LED strips, with one protrusion forming a space in between the reflector and the body for placement of the ballast. The reflector can comprise of five protrusions, with a central protrusion having a horizontal top portion, two triangular protrusions, and two slanting protrusions. The body can be comprised of a top horizontal portion that borders downwardly slanting portions, with each slanting portion further bordering downwardly vertical portions, with all portions running parallel in respect to each other. The fixture can comprise one or more ballasts in a compartment formed by the body by attaching the ballast inside of the compartment to the horizontal top portion of the body. The fixture can comprise a mounting frame attached to the lower tip of the downwardly portion of the body and running parallel with the body. The mounting frame can creates a U shaped gap. The door can be secured by matching screw holes on the mounting frame. An end frame can be attached in transverse direction to the body. The body can be made from a single piece of metal. The bracket can rest on the body with a hanging member at the first end and is detachably attached to the body at the second end. The fixture can further comprise a slot on the body for having the first end of the bracket go through to allow for the bracket to pivot. The slot can be a T-slot. The slot can be a vertically downwardly portion of the body. The bracket can sit on the slot with a member hanging out from the body and being in a gap formed in between a mounting frame and the body. The reflector can be attached to the bracket with screws. The fixture can further comprise LED strips placed on the reflector on the side of the reflector not facing the body. The bracket holding the reflector can be removed altogether through a slot on the body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 illustrates a bottom perspective view of the fixture with its door open.
[0007] FIG. 2 is a bottom view of the fixture.
[0008] FIG. 3 is a top view of the light fixture.
[0009] FIG. 4 is a side view of the light fixture with end panel.
[0010] FIG. 5 is a top perspective view of the light fixture.
[0011] FIG. 6 is a bottom perspective view of the light fixture.
[0012] FIG. 7 is a perspective view of the light fixture.
[0013] FIG. 8 illustrates the different components of the light fixture.
[0014] FIG. 9A illustrates a door of the light fixture that holds a lens.
[0015] FIG. 9B illustrates a door of the light fixture that holds a lens.
[0016] FIG. 10 illustrates the different components of a door.
[0017] FIG. 11 illustrates a side view of the light fixture without the end frame.
[0018] FIG. 12 illustrates the light fixture with the reflector and the door in an open position.
[0019] FIG. 13 illustrates a side perspective view of the door of the light fixture.
[0020] FIG. 14 illustrates a side perspective view of the door of the light fixtures.
[0021] FIG. 15 illustrates assembled door with lens, frame, and hinge.
[0022] FIG. 16 illustrates assembled door with lens, frame, and hinge.
[0023] FIG. 17A illustrates a bracket attached.
[0024] FIG. 17B illustrates a bracket attached.
[0025] FIG. 18A illustrates short side of the door.
[0026] FIG. 18B illustrates short side of the door.
[0027] FIG. 19A illustrates a side view of the bracket.
[0028] FIG. 19B illustrates a perspective view of the bracket.
[0029] FIG. 19C illustrates the shape of a member that goes through a T-slot.
[0030] FIG. 20 illustrates a fixture body with a flat reflector.
[0031] FIG. 21A illustrates frame of the door with lens holders.
[0032] FIG. 21B illustrates frame of the door with lens holders.
DETAILED DESCRIPTION OF THE INVENTION
[0033] The present invention provides a hanging light (high bay) that allows easy access to ballasts and LED light strips. In this embodiment, a body ( 66 ) is provided having a horizontal top surface ( 53 ) with slanting downward sections ( 54 ) on each side. Each slanting down portion has attached thereto a vertical section ( 67 ). The vertical section ( 67 ) and the horizontal top surface ( 53 ) are perpendicular to each other. The horizontal top surface can have a hanger ( 21 ) for wires to pass the junction box and/or for hanging the fixture from the ceiling. The slanting downward sections ( 54 ) can have plurality of vents ( 52 ) that allow for movement of air and cooling down of the light fixture. Members ( 14 ) for hanging the light fixture to the ceiling project upward, in the illustrated embodiments from the slanting portions. An end frame ( 57 ) can be attached to each side of the body. The end frame ( 57 ) can have openings ( 59 ) for passage of wires. A door ( 56 ) is attached to a long side of the body ( 66 ) with a hinge ( 55 ). The door ( 56 ) holds a lens ( 68 ) and pivots to an open and a closed position. The door ( 56 ) can have holders ( 69 ) to keep the lens ( 68 ) in place.
[0034] FIG. 1 illustrates a bottom perspective view of the light fixture with its door ( 56 ) open. The fixture has LED strips ( 2 ) fixed on a reflector ( 51 ) which is attached to the body ( 66 ) of the light fixture. End frames ( 57 ) are placed at opposite sides of the body ( 66 ). The end frame ( 57 ) can have an opening ( 59 ) for passage of wires. Member ( 14 ) can be used to hang the fixture from the ceiling. The body ( 66 ) also has a mounting frame ( 67 ) with screw holes ( 70 ) which correspond to screw holes ( 70 ) on door ( 56 ), and allows for securely holding the door ( 56 ) in place with a fastener like a screw. The mounting frame ( 67 ) generally runs parallel to the long side of the light fixture.
[0035] FIG. 2 is a bottom view of the fixture. Four LED strips ( 2 ) are placed on top of reflector ( 51 ). The reflector can have four cavities ( 58 ) for placement of the LED strips ( 2 ). The Reflector central protrusion ( 61 ) can be more bulky than other portions of the reflector ( 51 ) surrounding the LED strip ( 2 ). The inside of the Reflector central protrusion ( 61 ) can be used to place electronics such as ballast.
[0036] FIG. 3 is a top view of the light fixture. The horizontal top surface ( 53 ) of the LED light borders slanting portions ( 54 ) on each side and an have a hanger ( 21 ). The slanting portions ( 54 ) can have a plurality of vents ( 52 ). Door ( 56 ) is pivotally attached to the body ( 66 ) via hinge ( 55 ).
[0037] FIG. 4 is an end view of the light fixture with end frame ( 57 ). Also shown is pivotally attached door ( 56 ). Opening ( 59 ) on end frame ( 57 ) allows for passage of wires. Member ( 14 ) allows for hanging the fixture from ceiling. Also shown is mounting frame ( 67 ). A gap forms in between the mounting frame ( 67 ) and the body ( 66 ). This gap allows for screwing the door ( 56 ) to the mounting frame ( 67 ). Also shown is resting member ( 72 ) of the bracket which extends from a T-slot in the body and is positioned in this gap.
[0038] FIG. 5 is a top perspective view of the light fixture. The horizontal top portion ( 53 ) of the light fixture borders slanting portions ( 54 ) on each side. The horizontal top portion ( 53 ) can also have a hanger ( 21 ). The slanting portion ( 54 ) can have a plurality of vents ( 52 ). Door ( 56 ) is pivotally attached to the body via hinge ( 55 ). Door ( 56 ) has holders ( 60 ) for holding the lens. Member ( 14 ) allows for hanging the fixture from ceiling. An end frame ( 57 ) with an opening for passage of wires ( 59 ) is attached to each end of the body ( 66 ). A gap forms in between the mounting frame ( 67 ) and the body ( 66 ). This gap allows for screwing the door ( 56 ) to the mounting frame ( 67 ). Also shown is resting member ( 72 ) of the bracket which extends from a T-slot in the body and is positioned in this gap.
[0039] FIG. 6 is a bottom perspective view of the light fixture and FIG. 7 is another perspective view of the light fixture. Four LED strips ( 2 ) are placed in each cavity ( 58 ) of a reflector ( 51 ) attached to the body ( 66 ) of the light fixture. A reflector ( 51 ) with different number of cavities ( 58 ) can be used. The cavities ( 58 ) of the reflector ( 51 ) are caused by upward protrusions in the reflector ( 51 ). The central protrusion ( 61 ) can have a flat top surface and straight or slanting side portions. The central protrusion ( 61 ) creates a cavity that allows for passage of wires from opening ( 35 ) of the end frame ( 57 ). The additional protrusions can be triangular in shape ( 62 ) formed by two slanting portions joining each other. The reflector can have a single slanting protrusion ( 63 ) at each side to fit against the body. Also illustrated is mounting frame ( 67 ) with matching screw holes ( 70 ) with door ( 56 ) for securing the door ( 56 ) to the body ( 66 ).
[0040] FIG. 8 illustrates the different components of the light fixture. LED strips ( 2 ) are attached to the reflector ( 51 ), which itself is attached to two brackets ( 68 ) (one on each side). The brackets ( 68 ) are pivotally attached to the body ( 66 ) at one end. The brackets ( 68 ) can be attached to the reflector ( 51 ) at one or more locations. The brackets ( 68 ) can be made of steel and the reflector ( 51 ) made of aluminum. The bracket ( 68 ) allows for moving the reflector ( 51 ) out of the way so a technician can access ballasts ( 25 ) while the light fixture is still hanging. As shown in FIG. 36 , ballasts ( 25 ) reside under the space created by the central protrusion ( 61 ) of the reflector ( 51 ). This space allows for placing one or more ballasts ( 25 ) and electronically connecting the ballasts ( 25 ) to a power source. Also illustrated is the door ( 56 )) which is pivotally attached to the body ( 66 ) with hinge ( 55 ).
[0041] FIGS. 9A and 9B illustrate a door ( 56 ) that holds a lens ( 16 ). The door ( 56 ) has a frame and lens holders ( 60 ) are placed inside the frame of the door. The door ( 56 ) is pivotally attached to a hinge ( 55 ) as illustrated in FIG. 37B .
[0042] FIG. 10 illustrates the different components of a door ( 56 ). The door ( 56 ) can be made from a frame ( 64 , 65 ), lens holders ( 60 ), and a piano type hinge ( 55 ).
[0043] FIG. 11 illustrates a side view of the light fixture without the end frame ( 57 ). LED strip ( 2 ) is sitting in each of the four cavities ( 58 ) of the reflector ( 51 ). A door ( 56 ) with a lens holder ( 60 ) is pivotally attached to the body ( 66 ) of the light fixture. Also illustrated in hanging member ( 14 ).
[0044] FIG. 12 illustrates the light fixture with the reflector ( 51 ) and the door ( 56 ) in an open position. The door ( 56 ) and the reflector ( 51 ) are designed to pivot in opposite directions, i.e., one pivots clock-wise and other pivots counter-clock-wise. In such open position, the ballasts ( 25 ) attached to the body of the light fixture are accessible to a technician. The reflector ( 51 ) and the door ( 56 ) are pivotally attached to opposite sides of the body of the light fixture.
[0045] FIGS. 13 and 14 illustrates a side perspective view of the door of the light fixture having a lens ( 16 ), a frame ( 64 , 65 ), and a hinge ( 55 ) running alone one side for attachment to the body of the light fixture. Also illustrated in FIG. 14 is the lens holder ( 60 ).
[0046] FIGS. 15 and 16 illustrates assembled door ( 56 ) with lens ( 69 ), frame ( 64 , 65 ), and hinge ( 55 ). The door ( 56 ) is pivotally attached to the body ( 66 ) of the light fixture via the hinge ( 55 ). FIG. 15 illustrates the side of the door ( 56 ) facing inside of the fixture and FIG. 16 illustrates the side of the door ( 56 ) facing outside of the fixture.
[0047] FIG. 17 illustrates the bracket ( 68 ) which is attached to the reflector ( 51 ) and allows the reflector ( 51 ) to pivot. The bracket has a resting member ( 72 ) that passes through a T-slot ( 71 ) on the vertical portion of the body ( 73 ) and rests on outside of the vertical portion of the body ( 73 ). The bracket ( 68 ) with or without the reflector ( 51 ) can be removed from the T-slot ( 71 ) as needed. The resting members sits in the gap formed in between the mounting bracket ( 67 ) and the vertical portion if the body ( 73 ).
[0048] FIGS. 18 (A and B) illustrate short side of the short side of the door frame ( 65 ) holding the lens. A side view of the hinge ( 55 ) attached to the short side of the door frame is visible in these views.
[0049] FIG. 19 illustrates the bracket ( 68 ) with a second end ( 74 ) and a first end ( 75 ). The first end ( 75 ) of the bracket in this embodiment is removably attached to the bracket ( 68 ). The member ( 72 ) is positioned outside of the body through slot ( 71 ). The member ( 72 ) is attached to a short vertical neck ( 76 ) at a ninety degree angle. After moving member ( 72 ) through slot ( 71 ), member ( 72 ) stabilizes the bracket ( 68 ). As illustrated in FIG. 17B , the T-slot is wider at certain positions. The member ( 72 ) can move through the slot ( 72 ) only at its widest point. The second end of the bracket ( 74 ) is screwed to the body to stabilize the bracket.
[0050] FIG. 20 illustrates a fixture with a flat reflector ( 51 ). LED strips ( 2 ) are attached (such as with a screw) to the flat reflector ( 51 ). Additional side reflectors ( 77 ) can be used in this embodiment. The reflector ( 51 ) is attached to the brackets ( 68 ).
[0051] FIG. 21A illustrates frame ( 64 ) of the door ( 56 ) with lens holders ( 60 ), with a close up provided in FIG. 21B .
[0052] In one embodiment, provided is a body ( 66 ) that provides a compartment for placement of ballasts ( 25 ), reflector ( 51 ) and LED strips ( 2 ). The body can be made from a long horizontal portion that makes the top of the fixture. The compartment in the body ( 66 ) is formed by one or more portions that come downward, such as a downwardly slanting portion ( 54 ) and/or a vertically downward portion ( 73 ). All these portions run parallel to each other on the long side of the body ( 66 ) the end of the downwardly portion ( 73 ) can further comprise a mounting frame ( 67 ) which creates a U shaped gap. The body with all these portions can be made from a single piece of metal. An end frame ( 57 ) can then be placed at each end of the body to surround the compartment formed by the body. The end frames are perpendicular (transverse) in direction (90 degrees) to the long side of the body. One or two (or more) ballasts ( 25 ) can be placed in the compartment formed by the body ( 66 ), preferably by attaching the ballast ( 25 ) inside of the compartment to the horizontal top portion of the body. The body ( 66 ) can have a T-slot ( 71 ) on one or more of its downwardly portions, such as a vertically downwardly section ( 73 ) for resting a bracket in perpendicular (transverse) direction to the long side of the body ( 66 ) and in parallel fashion to the end frame ( 57 ). The bracket ( 68 ) sits on the T-slot ( 71 ) with a member ( 72 ) hanging out from the body and being in a gap firmed in between the mounting frame ( 67 ) and the body ( 66 ). A reflector ( 51 ) is attached to the brackets ( 68 ) with screws. The reflector ( 51 ) can be flat or have protrusions, with at least a central protrusion ( 61 ) that forms a cavity in between the body ( 66 ) and the reflector ( 51 ) that allows for placement of ballasts ( 25 ). LED strips ( 2 ) are placed on the reflector ( 51 ) on the side of the reflector ( 51 ) not facing the body ( 66 ). The bracket ( 68 ) holding the reflector ( 51 ) can be pivoted or removed altogether. A door ( 56 ) with a lens ( 16 ) is pivotally attached with a hinge ( 55 ) in parallel fashion with the body ( 66 ) and in a closed position covers the compartment that is formed by the body ( 66 ) and the end frame ( 57 ). The door is secured by matching screw holes ( 70 ) to the mounting frame ( 67 ). The hinge ( 55 ) is attached to the mounting frame ( 67 ) on one side of the body ( 66 ) and the door ( 56 ) is secured to the screw holes ( 70 ) on the additional mounting frame ( 67 ). When a technician seeks to access the light fixture, the technician has to first remove the screws to free the door ( 56 ), and pivot the door ( 56 ) to one side. The technician can then pivot the reflector ( 51 ) to opposite direction of the door ( 56 ) or even remove the reflector ( 51 ) by removing the bracket from the T-slot.
REFERENCE TO NUMBERS
[0053] 2 . LED Strip
[0054] 16 . lens
[0055] 21 . hanger
[0056] 25 . ballast
[0057] 51 . Reflector
[0058] 52 . vents
[0059] 53 . horizontal portion
[0060] 54 . slanting portion
[0061] 55 . hinge
[0062] 56 . Door
[0063] 57 . End Frame
[0064] 58 . Cavity
[0065] 59 . Opening for passage of wires
[0066] 60 . Lens holder
[0067] 61 . Reflector central protrusion
[0068] 62 . Reflector triangular protrusion.
[0069] 63 . Reflector slanting protrusion
[0070] 64 . Door frame long side
[0071] 65 . Door frame short side
[0072] 66 . body
[0073] 67 . Mounting frame
[0074] 68 . bracket
[0075] 70 . screw holes
[0076] 71 . T-slot
[0077] 72 . Resting member
[0078] 73 . Vertical portion
[0079] 74 . Second end of bracket
[0080] 75 . first end of bracket
[0081] 76 . neck attached to resting member
[0082] 77 . side reflector | Provided is a light fixture comprising: a) a body for attaching one or more ballast; b) a bracket haying a first and a second end that is pivotally attached at the first end to the body, and c) a reflector for placement of one or more LED (light emitting diode) strips attached to the bracket. The fixture can further comprise a door with a lens pivotally attached to the body, wherein the ballast is accessed by pivoting the reflector and the door in opposite directions. | 5 |
CROSS-REFERENCES TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
MICROFICHE APPENDIX
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the field of soil erosion control. More specifically, the invention comprises a new method of manufacturing and packing sections of silt fence.
2. Description of the Related Art
Soil erosion is a constant problem in construction work, where the bare soil must often be left exposed to rain for considerable periods. Traditionally, hay bails were staked to the ground in order to slow water run-off down bare slopes. While effective, this technique was labor intensive and had inherent shipping and storage problems—owing to the weight of the bales. The more modem approach is to use silt fencing.
A silt fence is a porous barrier fabric which is attached to and stretched between a number of stakes. The stakes are driven into the ground in positions needed to stretch the fabric across the anticipated direction of water flow. The fabric is designed to allow the passage of water, but to encourage the deposition of any sediment being carried in the water. The result is that sediment builds up on the upstream side of the fabric, with the silt fence ultimately tending to bury itself.
Numerous prior art patents pertain to silt fences and methods of producing and installing them. These prior art patent include U.S. Pat. Nos. 6,158,923, 6,053,665, 5,944,114, 5,921,709, 5,915,878, 5,622,448, 5,345,741, and 4,756,511.
FIG. 1 illustrates a typical prior art silt fence. A plurality of evenly spaced stakes 12 are provided. Silt fabric 10 is placed over stakes 12 , then affixed to stakes 12 by staples or other fastening means. The user places the fence in position by driving points 16 of stakes 12 into the ground, with the lower portion of silt fabric 10 being buried in a shallow trench.
While FIG. 1 illustrates the components of a silt fence, it does not accurately reflect how such fences are typically manufactured. FIG. 2 shows roll 28 , which is formed by a plurality of stakes 12 attached to silt fabric 10 . A silt fence is typically made by chucking center stake 36 in a rotating carriage, then attaching the starting end of silt fabric 10 to it. Center stake 36 is then rotated to wind silt fabric 10 around itself. At fixed intervals, another stake 12 is brought in and stapled to silt fabric 10 . The winding continues until a complete roll 28 is formed. It is then taped, tied, or banded to lock it in position for transportation and storage.
FIG. 2 illustrates roll 28 having eight stakes 12 . Roll 28 can be made larger or smaller. Those skilled in the art will realize that the prior art manufacturing process described is an intermittent one; i.e., once a roll is formed, the process is stopped to remove that roll and start forming a new one. This represents a disadvantage, in that it limits the speed of production. It also causes problems with any printing performed on silt fabric 10 . Many purchasers want to have their names and logos printed on the silt fabric itself The best printing methods for this purpose are those using a wet printing plate. The printing dyes employed are dissolved in a liquid carrier, which must be quite volatile (in order for the printing to dry rapidly). Thus, the wet printing process is very sensitive to any pauses in the production. If the feed of silt fabric 10 is halted for significant periods, the dye solutions will dry on the printing plate and the print quality will deteriorate. The prior art intermittent production process therefore compromises printing quality on silt fabric 10 .
The roll method has two additional drawbacks. First, rolls 28 do not stack efficiently, since their circular cross section inherently produces wasted space. Second, roll 28 is cumbersome to install. Those skilled in the art will realize that roll 28 —as illustrated in FIG. 2 —is modestly sized. Often these rolls will be 100 feet long. A typical installation would be in the range of 100 feet to 10,000 feet long. It is very cumbersome to unroll many hundreds of feet of silt fencing packaged in the roll form.
It is also fairly common to need a length which is less than the entire roll. In such a case, the user must lift roll 28 by its ends and unroll the needed amount. The user then cuts the needed amount free from the rest of the roll. As roll 28 can be heavy, this approach often means that two people are needed.
Alternatively, the user can unroll roll 28 by rolling it along the ground until the needed amount is laid flat. The user then removes the needed amount and re-rolls roll 28 . This approach requires the user to lift a heavy object (roll 28 ) off the back of a truck, perform the operation, and then lift it back on to the truck.
Accordingly, the prior art methods of packing silt fencing are limited in that they:
1. Typically require an intermittent manufacturing process, thereby limiting production speed and compromising print quality;
2. Do not lend themselves to efficient packing; and
3. Render the silt fence cumbersome to deploy.
BRIEF SUMMARY OF THE INVENTION
The present invention eliminates the disadvantages inherent in the prior art by placing the silt fence in a flat-pack configuration. With reference to FIG. 4, stakes 12 are evenly spaced and silt fabric 10 is evenly draped over them by any suitable means to form a series of loops 14 . Silt fabric 10 is then attached to each stake 12 at the point where it drapes over each stake 12 .
Stakes 12 are then moved closer to each other as shown in FIG. 6, with the result that loops 14 grow longer and more narrow. FIG. 7 shows stakes 12 bunched tightly together, with the result that loops 14 are now very long and very narrow. As stakes 12 are held in position, loops 14 are then wrapped around stakes 12 as indicated by the arrow.
FIG. 8 shows stakes 12 —still being held in position—with loops 14 wrapped around them. In FIG. 9, securing straps 24 have been placed around the assembly to create flat pack 26 . This entire process can be carried out on a linear assembly line without intermittently stopping the motion.
The objects and advantages of the present invention are:
1. To provide an improved method of packing and storing silt fence which can be carried out on a linear assembly line without intermittently stopping the linear motion;
2. To provide an improved method of packing and storing silt fence which does not waste storage space; and
3. To provide an improved method of packing and storing silt fence which enables the user to easily pull off a short section of silt fence without having to lift the entire pack.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is an isometric view, showing a completed silt fence.
FIG. 2 is an isometric view, showing the prior art method.
FIG. 3 is an isometric view, showing the manufacture of the present invention.
FIG. 4 is an isometric view, showing the manufacture of the present invention.
FIG. 5 is an isometric view, showing the addition of staples.
FIG. 6 is an isometric view, showing the bunching of the loops.
FIG. 7 is an isometric view, showing the completion of the bunching of the loops.
FIG. 8 is an isometric view, showing the wrapping of the loops around the stakes.
FIG. 9 is an isometric view, showing the strapping of the flat pack.
REFERENCE NUMERALS IN THE DRAWINGS
10 silt fabric
12 stake
14 loop
16 staple
18 stake top
20 starting color patch
22 ending color patch
24 securing strap
26 flat pack
28 roll
30 point
32 first stake
34 last stake
36 center stake
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 illustrates the major components involved in the process. A plurality of stakes 12 are evenly spaced along a production line by any conventional means. A strip of silt fabric 10 is then fed to the top of the plurality of stakes 12 . The illustration simply shows a long ribbon of silt fabric 10 being draped over stakes 12 . This can also be accomplished by a linear feed of silt fabric 10 (such as off a large master roll) descending down over a line of moving stakes 12 . In the example shown in FIG. 3, an assembly line could move stakes 12 from right to left in the view, as the ribbon of silt fabric 10 is deposited over their tops.
FIG. 4 shows silt fabric 10 laid evenly over stakes 12 . However this operation is carried out, significant result is that silt fabric 10 must be placed so as to create a plurality of even loops 14 between stakes 12 . The loops need not be exactly alike, but it is important to have them approximately equal in length.
While stakes 12 and silt fabric 10 are in the relationship shown in FIG. 4, silt fabric 10 must be attached to stakes 12 . FIG. 5 —a detail view—shows the addition of stapes 16 . Two or more staples 16 are driven through each portion of silt fabric 10 that lies on top of a stake 12 . Once staples 16 are in place, the length of each loop 14 is fixed.
The reader should appreciate that while staples are particularly effective from a strength and cost standpoint, many other types of fasteners could be used. These would include nails, screws, adhesives, stitching, slats, tie cords, and the like.
The next step in the manufacturing process is shown in FIG. 6 . After staples 16 are in place, stakes 12 are pushed closer together—as shown by the arrow. The result is that loops 14 begin to lengthen and become more narrow. This process continues until stakes 12 are bunched closely together in a single plane, as shown in FIG. 7 . The reader will note that loops 14 are by this point long and narrow. It is advantageous to use gravity to orient loops 14 by allowing them to descend below the production line during this process. However, the use of gravity is not the only way to accomplish this. A set of guiding rods placed through each loop 14 could be used to pull them in any direction desired. Many other conventional mechanisms could be employed.
Once the bunching of stakes 12 is complete, the plurality of loops 14 is wrapped around stakes 12 in the direction indicated by the arrow. Stakes 12 are held in position as loops 14 are wrapped snugly around them. This wrapping process serves to pull stakes 12 even closer together.
FIG. 8 shows stakes 12 with the plurality of loops 14 wrapped tightly around them. The reader will observe that each loop 14 has been pressed flat. As silt fabric 10 is thin and highly flexible, this operation does not place undue stress on the fabric.
The assembly shown in FIG. 8 will not remain in its compact state without an additional step. FIG. 9 shows the addition of two securing straps 24 . These can be metal bands, plastic bands, tape, or the like. Their function is to tightly bind the components together. Once bound, the result is a unitary structure referred to as flat pack 26 . Flat pack 26 can be handled as a unit. Many flat packs 26 can be vertically stacked with very little waste of space. Flat packs 26 can also be placed on their narrow edges and stored in that fashion with very little waste of space.
The reader should appreciate that although stakes 12 have been illustrated as square, the method can be employed for stakes having many different cross-sections and characteristics.
When a user wants to pull the silt fence out of flat pack 26 , it is important to know which end to start from. The user first removes securing straps 24 . The user then pulls the portions of loops 14 resting over the top of flat pack 26 off to the left in FIG. 9 . The user then pulls first stake 32 off to the left. The user then continues moving first stake 32 to the left. This action results in each successive loop 14 being unfurled out into a tight sheet and pulling the next stake 12 out of flatpack 26 .
Those skilled in the art will realize that flat pack 26 can be made with many more stakes 12 than are shown in FIG. 9 . In such a case, the user may not wish to use all of the flat pack. If so, the user simply stops pulling at the desired point and makes a transverse cut across silt fabric 10 . He or she is able to pull off any desired amount without having to lift or move flat pack 26 .
So long as the user starts with first stake 32 , the unpacking operation will be smooth. Those skilled in the art will realize, however, that if the user starts pulling with last stake 34 (pulling it to the right as shown in FIG. 9 ), the operation will not be smooth. If the user begins pulling with last stake 34 , he will have to pull the loops under flat pack 26 in order to start pulling last stake 34 free. This is difficult without moving the whole flat pack 26 . The goal is to have flat pack 26 remain stationary while the user pulls off the desired length of silt fencing. Thus, it is important to be sure the user starts pulling on the correct end.
It is also important to ensure that flat pack is oriented as shown in FIG. 9; i.e., with the ends of loops 14 on its upper surface. If it is inverted, then the user will have difficulty pulling loops 14 out from beneath flat pack 26 .
To ensure these goals, a color designation system is employed. First stake 32 has starting color patch 20 on its upper surface at its upper end (nearest the viewer in FIG. 9 ). Likewise, last stake 34 has ending color patch on its upper surface at its upper end. The colors employed should be easily distinguished—such as blue and yellow. These color cues will assist persons stacking flat packs 26 . As an example, when placed on a truck, flat packs 26 should be placed with the color patches facing upward, and with first stake 32 toward the rear of the truck (or toward whichever side the silt fencing will be unloaded from).
The manufacturing operations described in FIGS. 3 through 9 could be carried out using a variety of mechanisms. The actual mechanisms employed are not significant to the present invention. However, it is important for the reader to understand that all of these operations can be carried out while stakes 12 are moving down a linear assembly line. In FIGS. 3 and 4, silt fabric 10 can be properly fed onto the plurality of stakes 12 as stakes 12 move transversely down an assembly line (with the stakes moving from right to left as shown in FIG. 4 ). Staples 16 can also be added while the line continues to move.
The bunching operations described in FIGS. 6 and 7 can be accomplished by transferring stakes 12 onto a decelerating conveyor. A desired length of silt fencing is then cut free and the wrapping of loops 14 (FIGS. 7 and 8) can be performed. There is no need to stop and start the moving assembly line, as in the prior art rolling approach.
Accordingly, the reader will appreciate that the proposed invention can readily create a silt fence stored in a convenient flat pack. The invention has further advantages in that it:
1. Can be carried out on a linear assembly line without intermittently stopping the linear motion;
2. Provides an improved method of packing and storing silt fence which does not waste storage space;
3. Enables the user to easily pull off a short section of silt fence without having to lift the entire pack; and
4. Enables the user to easily inventory a stack of silt fencing since the flat pack has little wasted space.
Although the preceding description contains significant detail, it should not be construed as limiting the scope of the invention but rather as providing illustrations of the preferred embodiment of the invention. As an example, many different methods could be employed to attach silt fabric 10 to stakes 12 . As another example, mechanisms could be employed to align loops 14 in a single orientation, rather than using gravity to align them by suspending them below stakes 12 . Thus, the scope of the invention should be fixed by the following claims, rather than by the examples given. | A method for packaging conventional silt fencing and a product produced by the method. Silt fabric is attached to a number of evenly spaced stakes. The stakes are then bunched together so that the silt fabric hangs between the stakes in descending loops. The bunching is continued until all the stakes lie close together in one plane. The loops of silt fabric are then wrapped tightly around the stakes. Securing bands are then placed around the assembly to create a flat pack. | 4 |
BACKGROUND
This invention is directed to sweatbands of the type used by athletes in exercising.
Sweatbands, such as headbands and wristbands, are commonly used by athletes to absorb perspiration, and to a lesser degree, to keep hair out of the eyes. A common sweatband is formed of a double layer of a stretchable, terry cloth-like material, which can be stretched to conform to different size heads and wrists. and absorbs sweat.
A difficulty with this type of sweatband is it can be too loose over small heads and small wrists, such as those of children. In addition, this type of sweatband can be too snug when used by large sized adults. Moreover, with use, the elasticity of the stretchable material gives way, and the snugness is lost with the result that the sweatband can slide out of position. Further, conventional sweatbands are uncomfortable when stretched over headphones and other music-generating devices used by many exercisers.
Another disadvantages of conventional sweatbands is that they can be singularly unattractive. The patent attorney writing this application has been accused by his fashion-conscious teenage daughters of looking like a "dork" when jogging with a conventional sweatband stretched over stereo earphones. As is evident from apparel worn at most exercise classes, the fashion attractiveness of exercise clothes is important to many exercisers.
Rather than wearing unsightly headbands, some exercisers take a bandanna, roll it up, and tie it around their head. Although this can be effective in keeping hair out of the eyes, these headbands absorb very little sweat, with the result that a serious exerciser can have sweat dripping into and stinging the exerciser's eyes. Moreover, the headbands are held in place merely by a knot tied at the back, and this knot can easily come lose, resulting in the bandanna slipping out of position. This can become a serious problem when the headband slips over the eyes just at the time the exerciser is about ready to return a forehand in tennis or shoot a critical jumpshot in basketball.
Accordingly, there is a need for a comfortable, adjustable, highly absorbent, and attractive sweatband.
SUMMARY
The present invention is directed to sweatbands that meet this need. A sweatband according to the present invention comprises an elongated, decorative, cloth element and a water-absorber retained by the cloth element. The cloth element is made of a material capable of transmitting water, and has opposed end portions, which are sufficiently long to extend around a body part such as a wrist or a head. The water-absorber is soft and comfortable when worn, and sufficiently flexible to conform to the body part. The band can be placed around the body part and the cloth element end portions can then be secured together so that the band can absorb sweat from the body part, sweat transmitting through the cloth element into the water-absorber.
Typically the cloth element is formed of a stretchable material, such as a combination of spandex and a fibrous material. Dependant upon the material utilized, the cloth element can also absorb sweat as well as transmit sweat. Typically the cloth element comprises a tubular portion that contains the water-absorber, which can be a relatively flat piece of open cell synthetic foam.
It has been noted that at the interface between the end of the water-absorber and the cloth element, the cloth element can have an unsightly pucker, i.e., a wide spot, when the sweatband is wrapped around the body part. In order to avoid this problem, preferably the end portions of the cloth element are tapered, being widest proximate to the water-absorber, and the water-absorber end portions are also tapered.
The cloth element end portions can be secured together by tying them together. More preferably, the end portions are provided with connectors, such as a strip of Velcro brand synthetic material that can be fastened to itself.
The present invention overcomes disadvantages of prior art sweatbands because it is formed from two separate elements, namely the cloth element and the water-absorber. The water-absorber can be chosen to maximize water absorption, without concern for aesthetics, because it is covered by the cloth element. Thus, the water-absorber can be much more absorbent than the present conventional sweatbands. Additionally, the water-absorber can be a soft flexible material that when placed against the body, gives the wearer a cushioned feeling, similar to a pillow resting on the forehead or wrist. The cloth element can be made decorative to display sharp, clear images and designs. For example, the cloth element can be formed from a cloth segment rolled to resemble a rolled bandanna. Moreover, the sweatband can be easily adjusted to precisely fit the wrist or head to provide maximum comfort to the user.
DRAWINGS
These and other features, aspects and advantages of the present invention will become better understood from the following description, appended claims, and accompanying drawings where:
FIG. 1 is of a perspective view showing a sweatband according to the present invention being placed around the head of the user;
FIG. 2 is a rear plan view of the sweatband of FIG. 1;
FIG. 3 is a rear plan view of the sweatband of FIG. 1, partially cut away to show the internal water-absorber;
FIG. 4 is a longitudinal section view of the sweatband of FIG. 1 taken on line 4--4 in FIG. 2;
FIG. 5 is a front plan view of a sweatband according to present invention, where the cloth element is rolled to have a bandanna appearance; and
FIG. 6 is a wristband according to the present invention.
DESCRIPTION
A sweatband 10 according to the present invention is sized to be wrapped around a head, as shown in FIG. 1. The sweatband comprises a cloth element 12 and a water-absorber 14 retained by the cloth element 12. The cloth element 12 comprises opposed end portions or tails 16 and a retaining portion 18 therebetween. The retaining portion 18 retains the water-absorber 14.
The cloth element 12 can be formed from a cloth segment that is stitched, as shown by stitching 20, so that the retaining portion 18 is tubular, having an operative portion in which the absorber 14 is retained.
Preferably the stitching is on the back side of the headband so that it is not seen. As shown in FIG. 4, all or a portion of the cloth material can be folded over to give a double layer and cover the stitching.
The cloth element end portions 16 can be sufficiently long that they can be tied together to secure the sweatband 10 in place. Preferably the distal ends of the end portions 16 are provided with strips 22 of a synthetic material that can be fastened to itself, such as Velcro brand fasteners. Preferably the Velcro fastener strips 22 are sufficiently long to provide adjustability in the length of the sweatband 10. This method of attachment is preferred since the user can easily adjust the sweatband to precisely fit the body part to provide maximum contact to the user. As shown in the Figures, the hook side 22a of the Velcro fastener strips 22 can be shorter than the receiving side 22b of the Velcro fastener strips 22.
It has been discovered that the cloth element can unattractively pucker or gather, i.e. become wide in a region proximate to the ends of the water-absorber 14. In other words, when the sweatband is placed in position, the region adjacent to the water-absorber 14 can look like a snake that has swallowed a mouse. To overcome this aesthetic problem, preferably the end portions 14a of the water-absorber 14 are tapered, as best shown in FIG. 3. Likewise, preferably the cloth element end portions 16 are tapered, being widest adjacent to the retaining portion and gradually tapering towards the fastener strips 22.
The cloth element 12 is made of a water transmissive material. Additionally, the cloth element 12 can be made of a water absorbent material. Preferably that material is stretchable to provide adjustability in the length of the sweatband and provide a snug, comfortable fit. Stretchability can be obtained by using an elastic material such as spandex, in combination with synthetic or natural fibrous materials. The fibrous material can be cotton, wool, acrylic, polyester, rayon, acetate, triacetate, nylon, and combinations thereof. Specific combinations that are suitable for sweatbands are 90% cotton/10% Lycra brand (Du Pont de Nemours, E. I. & Co., Wilmington, Del.) spandex; 80% nylon/20% Lycra; 85% nylon/15% Lycra; and 55% cotton/35% polyester/10% Lycra.
The cloth material can be any decorative material desired. It can be any color and have any pattern imprinted on it. Thus, users can color coordinate their headband and wristbands with the remainder of their exercise outfit. Preferably, the material utilized will display clear, sharp images and designs.
The water-absorber 14 preferably has a flat exterior surface 14b for aesthetic reasons and a flat interior surface 14c for comfort. The water-absorber 14 typically has a thickness of about 1/16 to about 1/2 inch, and a width of from about 1/2 inch to about 3 inches, and preferably from about 1 inch to about 11/2 inches. The water-absorber 14 is generally shorter in length than the cloth element, to provide the cloth element tails 16 to fasten the sweatband 10 in place.
The water-absorber, preferably, is made of a water-absorbent, comfortable, soft, flexible material that can conform to the shape of a body part. It can be made of natural sponge, or more typically, made of a synthetic foam material. Among the foam materials that are satisfactory are those described in Harper, Charles A. (editor), Handbook of Plastics and Elastomers, McGraw-Hill, New York (1975), chapter 7 by Barito, R. W. et al. which is incorporated herein by reference. Such materials include open cell polyurethane foam, polyvinyl chloride foam, foam rubber, phenolic foam, urea formaldehyde foam, and cellulose acetate foam.
As shown in FIG. 5, the cloth segment used for forming the sweatband 10 can be rolled up to simulate a bandanna, before it is stitched together. Thus the sweatband 50 can have all of the attractiveness of a bandanna, with the water-absorption comfort characteristics of a synthetic foam sponge.
The sweatband 10 is not limited to use as a headband. As shown in FIG. 6, a wristband 60 according to the present invention has substantially the same construction as the headband 10 shown in FIG. 1, except it is shorter in length; particularly the end segments are very short so that the water-absorber can enclose the entire wrist of the user.
The sweatband 10 is very easy to use. All that is necessary is to wrap it around a body part, and secure the two end portions together, either by tying or pinning the two end portions together, or when fastener strips 22 are provided, by attaching the two fastener strips 22 to each other.
Thus, a sweatband according to the present invention provides the functionality of conventional sweatbands, with more comfort, increased absorbency, and better aesthetics.
Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. For example, the water-absorber need not be one continuous element, but rather can be a series of discrete elements retained by the cloth element. Moreover, the water-absorber can be retained by the cloth element not only by forming a tubular space for it; retention can be effected by an adhesive, stitching, and/or a fastener, in addition to or instead of the tubular space. Therefore, the scope of the appended claims should not be limited to the description of the preferred versions contained herein. | A sweatband comprises an elongated, decorative, cloth element made of a stretchable material, and a water-absorber retained by the cloth element. The cloth element has end portions that can be secured together so that when the sweatband is placed around a body part, the band is held in place so the water-absorber can absorb sweat from the body part. The sweatband has a combination of comfort, high sweat absorbance. | 8 |
RELATED APPLICATION DATA
This patent application is a continuation-in-part of application Ser. No. 09/503,881, filed Feb. 14, 2000.
TECHNICAL FIELD
The invention relates to digital watermarking, and more particularly relates to watermark detection in multimedia content (e.g., still image, video and audio signals).
BACKGROUND AND SUMMARY
The reader is presumed to be familiar with digital watermarking technology. See, e.g., co-pending application Ser. No. 09/503,881, filed Feb. 14, 2000, entitled Watermark Reader and Embedder, the disclosure of which is incorporated by reference.
One objective of watermark detectors is to reject unmarked signals (e.g., image, audio, video signals) at the earliest possible stage of detection. The detector may conclude that a signal is unmarked based on quantitative evidence of the watermark (or lack thereof) in a signal suspected of having a watermark. The signal might be an unmarked component of a marked signal, or simply an unmarked signal. Also, in some cases, the signal, though previously marked, may appear to be unmarked due to removal or degradation of the watermark. By accurately identifying an unmarked signal at an early stage, the detector can avoid unnecessary processing. Also, the apparent absence of a watermark may trigger some action (or prevent an action) such as providing output indicating that the signal has been tampered with or controlling processing of the signal (e.g., preventing copying, playing or recording in copy protection applications).
A related objective of a watermark detector is measuring the strength of a watermark signal. Based on the watermark strength, the detector can assess whether a suspect signal has a valid watermark, and the extent to which a signal has been transformed. The detector can also determine the likelihood that a suspect signal includes a valid watermark or recoverable watermark message. Such an evaluation helps the detector allocate its processing resources on portions of the suspect signal that are likely to contain a valid watermark or recoverable watermark message.
The cited application describes a variety of techniques for detecting a watermark. Some of these techniques correlate attributes of a watermark signal with a signal suspected of containing a watermark. By measuring the extent of correlation, a watermark detector assesses whether a watermark is present, and in some cases, determines its orientation in the suspect signal. Related techniques detect a watermark signal by at least partially decoding a message from the suspect signal and then comparing attributes of the message with expected attributes to assess the likelihood that a watermark signal is present. These and other techniques may be used to compute a detection value that quantifies the likelihood that the suspect signal has a watermark.
One aspect of the invention is a method of using detection values ascertained from signals suspected of being watermarked to control the detection process. The detection values may be used to reject unmarked signals. In addition, they may be used to refine the detection process by focusing the detector on signals or portions of signals that are likely to contain a watermark and/or a recoverable watermark message. Each portion of a suspect signal may be defined by an orientation parameter (or set of parameters like rotation, scale, origin, shear, differential scale, etc.). Also, each portion may represent different orientations of the suspect signal, or a component of the signal.
Another aspect of the invention is a method for using two or more detection metrics to control the detection process. The multiple metrics could be derived from independent measurements in multiple stages or could be different features of the same measurement. Each detection metric evaluates detection values to control detection actions. One type of detection metric is a screen used to evaluate suspect signals or portions of a suspect signal for the presence of a watermark. Each stage evaluates detection values to assess whether a suspect signal, or portion of it, is marked.
Another aspect of the invention is a method for using absolute and relative detection measures to assess whether a suspect signal is marked. An absolute measure of detection represents quantitative evidence of a watermark signal in a suspect signal, and is usually evaluated independently from other detection values. A relative measure is based on the relative values of two or more detection values, which may be relative or absolute measures. A relative measure may be implemented by computing absolute detection values for different portions of a suspect signal and then computing a relative detection value as a function of the absolute detection values.
Both absolute and relative detection values may be evaluated relative to desired limits or thresholds to determine an appropriate action. One action is to reject the candidate signal associated with the detection value as being unmarked. Another action is to use the detection values to direct further actions of the detector. One advantage of using both absolute and relative detection values is that they usually contain complementary information. This complementary information helps in improving the watermark screening and detection process.
In one implementation, a detector computes detection values for different orientation parameter candidates, sorts the detection values in terms of likelihood of representing a valid watermark, and then takes a ratio of a top detection value relative to one or more lesser detection values. The orientation parameter candidates define an approximate orientation and/or location of a watermark in a suspect signal, and as such are associated with a portion of a suspect signal.
The foregoing and additional features and advantages of the present invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow diagram illustrating a watermark detection process.
FIG. 2 is a flow diagram showing a watermark detector that correlates a calibration signal with a suspect signal to compute detection values.
FIG. 3 is a flow diagram showing a watermark detector that computes detection values by comparing an expected signature with a watermark signature taken from a suspect signal.
FIG. 4 is a flow diagram of a process for screening un-marked signals based on detection metrics.
DETAILED DESCRIPTION
A watermark decoder detects a watermark in a suspect signal by computing evidence of watermark signal attributes in the suspect signal. The watermark signal attributes used in detection may be referred to as a calibration or synchronization signal (hereafter referred to as “calibration signal”). The calibration signal may be watermark signal attributes that correspond to message symbols embedded in a watermark. For example, a watermark message may include a “signature” of one or more symbols known to the decoder. In the process of encoding the signature, a watermark encoder modifies a host media signal to compute a composite signal with signal attributes of the signature. To detect the watermark in a suspect signal, a detector analyzes the suspect signal to find evidence of the signature. In this case, the calibration signal corresponds to the attributes of the composite signal used to encode the signature.
The calibration signal may also be an orientation watermark. To encode the orientation mark, the watermark encoder modifies the host signal to compute a composite signal with signal attributes of the orientation signal. To detect the watermark, a detector analyzes a suspect signal to find evidence of the orientation signal. In, this case, the calibration signal corresponds to the orientation signal. Both a message signature and an orientation signal may be embedded in a host signal. Some watermark signals may perform a dual function of encoding a signature and an orientation signal (e.g., a watermark signal acts as a signature and an orientation signal).
The following description uses the term “calibration signal” to broadly encompass watermark signal attributes used to identify a watermark in a suspect signal. Unless specified otherwise, the calibration signal should be construed to encompass watermark message symbols and/or an orientation signal used to detect a watermark.
To detect a watermark in a suspect signal, a detector computes quantitative evidence of the calibration signal. One form of evidence is a detection value indicating the extent to which a portion of the suspect signal has attributes that match those of the calibration signal. One such measure is a correlation value that quantifies the correlation between the calibration signal and a portion of the suspect signal. Another measure is the extent to which the known signature matches a signature computed from the suspect signal.
In the process of detecting a watermark in a suspect signal, the detector may analyze several portions of the suspect signal. In many watermark systems, a key specifies where a watermark is located in an un-modified watermarked signal. However, the decoder does not know whether there is a watermark in a suspect signal. Moreover, transformation of the composite signal may degrade the watermark and alter its orientation in a suspect signal. For many applications, the detector must search for the presence of a watermark and determine its orientation. This process is sometimes referred to as synchronization.
The synchronization process varies depending on the type of host and watermark signal. In images, the orientation of the watermark may change due to transformations of the host image (e.g., geometric transforms, spatial frequency transforms, phase transforms etc.). In audio, the location of the watermark may also change due to transformations (e.g., temporal shifting or scaling due to up-sampling or down-sampling, frequency shifting, phase shifting, etc.). In video signals, the location of the watermark may change due to these and other transformations.
Because these transforms may alter a watermark, the detector analyzes several different portions of the suspect signal to find evidence of it. A watermark key may help guide the analysis around certain portions of the suspect signal. Each of these portions has one or more orientation parameters that define a location (and/or orientation) in the suspect signal. In an audio sequence, the portion might be a time window or range of frequencies within an audio segment. In an image, the portion may be a two-dimensional spatial area or range of frequencies. To simplify the discussion, these portions of the suspect signal and their corresponding orientation parameter (or parameters) are generally referred to as candidates. The detector may compute a detection value for each candidate. Then, based on these detection values, the detector may assess whether a watermark is present, and the strength of the watermark.
FIG. 1 illustrates a process for detecting a watermark in a suspect signal. The detector identifies candidates in the suspect signal ( 100 , 102 ). A watermark key may be used to locate the candidates. Used in the watermark encoder to embed the calibration signal, the key generally specifies the location of the calibration signal in an unmodified marked signal. The detector then computes a detection value for the candidates ( 104 ). Next, it determines how to direct further detector actions based on the detection values ( 106 ). The detection value may be an absolute measure derived from a single candidate. Alternatively, it may be relative measure, computed by evaluating the detection value of one or more candidates relative to other candidates.
The detector may implement different actions based on evaluation of the detection values. One action is to reject the suspect signal as being un-marked. Another action is to use the detection measures to refine initial detection results. One way to refine the initial detection result is to select additional candidates that may increase the likelihood of accurate detection of a watermark and/or recovery of a message embedded in it. In short, the detector may use the detection values to focus detector resources on portions of the suspect signal that show promising evidence of a watermark and/or its calibration signal.
EXAMPLE EMBODIMENTS
FIG. 2 illustrates an example embodiment of a watermark detector that uses detection values to reject unmarked signals and to direct further detection actions. In this example, the detector correlates the calibration signal (or attributes of it) with the suspect signal ( 200 , 202 ). In performing the correlation process, the detector may use a watermark key to select initial portions of the suspect signal expected to contain a watermark. For example, the key may specify that the calibration signal has been encoded into marked signals in a particular spatial or temporal location in some given transform domain.
The correlation process ( 202 ) computes correlation values for candidate portions of the suspect signal that exhibit some evidence of the calibration signal ( 204 ). A variety of correlation methods may be employed, including, for example general matched filtering. Each candidate may be defined by one or more orientation parameters that describe its location and orientation within the suspect signal. The correlation values for each candidate are absolute detection values.
Next, the detector computes relative detection values based on the detection values calculated previously from the suspect signal ( 206 ). One example of a relative detection value is a ratio of a top absolute detection value to one or more lesser detection values. The detection process may repeat, iteratively refining candidates by adjusting their orientation parameters. In this case, there may be several sets of absolute detection values, and corresponding relative detection values for each set.
After the detector has computed detection values, it uses those values to control further detection actions. One action is to screen and reject un-marked signals (including un-marked portions of a signal, or portions where a watermark has been degraded) ( 208 ). Another action is to use promising detection values (e.g., those values falling within a desired range or exceeding a limit) to direct further detection operations on the suspect signal ( 210 ). The cited application provides an example of this action where orientation parameter candidates associated with top detection values are refined to improve detection and watermark message recovery. These types of actions can be used in detectors for different types of signals, including still image, audio and video signals.
FIG. 3 illustrates an example embodiment of a watermark detector in which the calibration signal is in the form of a signature. In this example, the detector begins by evaluating candidates in the suspect signal ( 300 ). As in the prior example, a watermark key may be used to specify an initial candidate location of a calibration signal, assuming that the suspect signal has been marked ( 302 ). Using the key to identify a candidate location of a: watermark, the detector attempts to decode the signature at the candidate location ( 304 ). Even if the suspect signal has been watermarked, the signature may be degraded and/or geometrically transformed due to manipulation of the watermarked signal.
Next, the detector evaluates the decoded signature relative to the signature used in the encoder (the expected signature) ( 306 ). One way to evaluate the signature is to measure the similarity between the decoded signature and the expected signature. An example of this similarity measure is the percentage agreement computation in the cited application. The similarity measure is another example of a detection value associated with a particular candidate.
Another way to evaluate the presence of a signature in the suspect signal is to perform correlation between signal attributes of the one or more expected symbols and the suspect signal. In fact, some implementations use correlation to decode watermark message symbols. The extent of correlation provides a measure of similarity between an expected signature and a signature observed in the suspect signal.
Based on the detection value, the detector may reject the signal as being un-marked ( 308 ). For example, if the detection value falls below a limit (either predetermined or adapted based on the suspect signal), then the detector may conclude that the associated signal is unmarked.
The detector may also quantify the extent of watermark degradation. For example, a low detection value represents significant degradation, while a high detection value represents minimal degradation. Such detection values are useful in signal authentication or copy control applications where the extent of degradation is used, for example, to determine whether the suspect signal is authentic or to control use of the suspect signal (e.g., enable/prevent its transmission, playback, recording or copying).
The detector may also use the detection value to refine its search for a valid calibration signal ( 310 ). For example, when the detection values fall within certain limits, then they direct the detector to focus its attempt to synchronize with the calibration signal around the orientation parameter or parameters that yield such detection values.
The cited application describes methods for computing detection values and using them to direct the actions of the detector. In one implementation, the detector performs multiple stages of detection. One form of calibration signal is an orientation signal. The detector performs correlation between an orientation signal and the suspect signal. Based on the measure of correlation, the detector determines whether to reject the suspect signal. A detection value derived from the correlation is then used to make a decision whether to reject the suspect signal as un-watermarked, or to allow it to proceed to later detection stages.
In a particular implementation in the cited application, an initial detection stage decides whether a watermark is present in a suspect image and, if so, provides estimates of orientation parameters to later detection stages. In other words, the initial detection stage acts as a classifier that discriminates between marked and unmarked images. The initial detection stage computes rotation and scale parameter candidates, and a measure of correlation for these candidates. It then determines whether to reject the suspect signal based on these measures of correlation. One test for screening unmarked signals is to compute a ratio of the top correlation value to other lesser correlation values for the candidates and then reject the signal as unmarked if the ratio does not exceed a limit. If the screen does not reject the suspect image, later detection stages refine the orientation parameter candidates by computing translation parameters (i.e. the origin of the watermark) and/or other parameters such as differential scale and shear.
For the orientation parameter candidate, the detector computes correlation between the orientation signal and the suspect signal. This correlation can be computed in the spatial domain, the Fourier magnitude domain, or some other transform domain.
In some applications, the detection strategy can be improved by performing one or more additional tests on candidates to control further detector processing actions.
One strategy, detailed below, uses a two stage test to reject un-marked images. This strategy uses both absolute and relative detection values. In experiments, this strategy rejects approximately 99% of unmarked images at an initial detection stage.
Ideally, the initial detection stage should allow all watermarked images to proceed to later detection stages but reject all unmarked images. However, any practical classifier would accept some number of unmarked images (false positives) and reject some number of marked images (false negatives). The goal is to minimize both the false positives and the false negatives.
FIG. 4 illustrates an example of a screening strategy that achieves this goal. Screen I —This screening strategy uses a detection metric based on relative detection values. Correlation values corresponding to the top candidates are used to compute the relative detection value. In particular, the relative detection value is computed as a ratio of a top correlation value to one or more lesser correlation values or combination of lesser correlation values (e.g., an average of the next N best correlation values). The detection value is compared to a pre-determined threshold T 1 . If the detection value exceeds T 1 , the detector proceeds to screen II. If the detection value fails to exceed T 1 , the suspect image is labeled an unmarked image and further processing ceases.
The correlation value may be computed in a variety of ways, depending on the nature of the orientation and suspect signals. For images, the correlation may be performed in one or more of the following domains: spatial, transform domain (e.g., Fourier domain), etc. In the case where the orientation signal is an array of impulse functions in the Fourier domain, the detector preferably computes the correlation in the Fourier domain. One measure of correlation analyzes the extent to which the impulse functions of the orientation signal are present in the Fourier Magnitude domain. This is a type of correlation strength and is referred to as Fourier Magnitude Correlation (FMC).
One way to compute the correlation strength in this context is to compute the dot product of the impulse functions of the orientation signal and the suspect signal in the Fourier Magnitude domain. The dot product is computed between the two signals after transforming the orientation signal to a candidate orientation (e.g., rotating and scaling it based on rotation and scale parameter candidates).
A related method is to perform an additional filtering process of the samples of the suspect signal in a neighborhood around the location of each impulse function and then summing the result of filtering around each impulse function location. This operating gives an indicator of the extent to which the impulse functions are present in the suspect signal. The neighborhood can be defined in a variety of ways, including a square neighborhood of samples centered at the location of the impulse function, or a neighborhood defined along a line or lines through the impulse function (e.g., horizontal line, vertical line, or radial line through the origin of the coordinate space).
One such filtering operation is to divide the sample in the suspect signal at the impulse location by an average of neighboring samples. If the average value is zero, then the filter result is set to some constant value. In one implementation, the result of filtering at each impulse function location in the Fourier magnitude domain is added to compute a measure of correlation.
A number of variations to this filtering operation are possible. One such variation is to insert a thresholding function before adding the filtering results. One example is a thresholding process that subtracts a first constant from each filtered result, and then clips values greater than a second constant to that constant value. The result of the thresholding operation is summed to derive a measure of correlation strength.
Screen II —In this screen, the correlation strength (corresponding to the top candidate after Fourier magnitude correlation) is compared to a pre-determined threshold T 2 . If the correlation strength exceeds T 2 , then the suspect image is allowed to proceed to the later detection stages. If the correlation strength fails to exceed T 2 , the suspect image is labeled an unmarked image and rejected.
Empirical data shows that for unmarked images, whose correlation strength is high, the remaining correlation values are also comparatively high. Therefore the resulting detection value is low. Screen I is well suited to reject such unmarked images. Most of the unmarked images that do make it beyond Screen I have lower correlation strengths and are rejected by the second step. The combination of the two screens gives high rejection rates.
The correlation strength is a useful figure of merit since it gives an approximate indication of how many orientation signal impulses (out of the total number of impulses in the orientation signal) were detected. Its use as a measure of the strength of the orientation signal can provide a further metric useful in later stages of detection.
A beneficial consequence of high rejection rates at an early detection stage is faster performance (speed of detection). Higher rejection means that the detector can avoid additional processing of later detection stages, which may by more computationally complex. As a result, the mean performance times are reduced.
The following points can be made about this two stage screening:
1) There are two screening stages to reject unmarked images. The first stage uses a metric based on a relative detection value. Images that pass this test are subjected to an additional screen where the correlation strength is compared to a predetermined threshold. Images that do not exceed this threshold are rejected; others proceed to the later detection stages.
2) The improved false positive rate means that the overall false positive statistics (all stages combined) improves commensurately.
3) The reduction in false positives translates into major performance improvements since very few (approximately 1%) of the unmarked images now reach the next stage of detection. In the cited application, additional stages used to refine the orientation parameter candidates (e.g., compute differential scale, shear, translation) and to decode a watermark message can be avoided or can be made more efficient by focusing on candidates that are more likely to represent a valid, recoverable watermark signal.
4) The correlation strength can be used as a figure of merit for the orientation signal.
5) The method can be extended to more than two screens.
6) In some cases, the order of the screens may be important. For example, interchanging the order of Screen I and Screen II may not provide good results. The order can be determined empirically using training data.
7) In each stage of detection, the detector can compute detection values based on one or more features of the suspect signal. Then, using possibly independent detection values front these stages, the detector can combine these values in metrics for screening and refining orientation parameters. Detection values may be considered independent if they are computed independently, rather than derived from each other. For example, a measure of correlation for an orientation signal in a watermark may be independent from a measure of similarity between expected and decoded message symbols from a watermark message.
The detector may compute different measures of correlation in each stage and evaluates a metric that combines information from these correlation measures to get improved rejection of unmarked signals.
The measures of correlation may be different in that they are computed in different domains (e.g., spatial, temporal, transform domains), are based on different orientation parameters, are computed for different parts of the suspect signal, or are based on different attributes of the watermark.
The features evaluated in each stage need not be measures of correlation. For example, one stage may evaluate the similarity between a decoded symbol or symbols from the suspect signal and symbol or symbols expected to be in a watermark message. A statistical analysis may be employed to indicate the likelihood that the decoded symbols represent expected symbols. Based on the similarity measure and/or statistical likelihood, the detection stage provides a detection value that can be combined with a detection value derived from another detection stage. In sum, effective detection metrics may be constructed by combining information from different stages. These detection metrics can then be used to control detector action, such as rejected unmarked signals or focusing further detection on portion of the suspect signal that appear more likely to have a valid, recoverable watermark.
Concluding Remarks
Having described the principles of my invention with reference to an illustrative embodiment, it should be apparent that the invention can be modified in arrangement and details without departing from such principles. Accordingly, I claim as my invention all such embodiments as may come within the scope and spirit of the following claims, and equivalents thereto.
To provide a comprehensive disclosure without unduly lengthening the specification, applicant incorporates by reference any patents and patent applications referenced above.
The particular combinations of elements and features in the above-detailed embodiments are exemplary only; the interchanging and substitution of these teachings with other teachings in this and the incorporated-by-reference patents/applications are also contemplated. | To enhance decoding of signals suspected of containing a watermark, a suspect signal is screened to compute detection values evincing presence and strength of a watermark. Screening strategies control detector actions, such as rejecting un-marked signals and improving synchronization of watermarks in suspect signals. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a photoelectric conductive motherboard for electronic modules and a photoelectric modular system.
2. Description of Related Art
Most devices and tools today contain electrical components. Even toys are becoming increasingly interactive with more and more electronic parts. Modern appliances, cars, and even furniture can contain electronic components. Both cell phones and computers have become necessities in most every household.
Although these devices benefit our society, they cause a significant problem: e-waste. Three million tons of e-waste is generated each year in the U.S. Landfills now contain 70-80% electronics, much of which contains hazardous materials such as lead, nickel, cadmium and mercury. Since e-waste also contains valuable elements, gold, copper, silver, palladium and platinum, discarded consumer electronics are not only a significant source of pollution, they are also a waste of our natural resources. Less than 20% of electronics are recycled. It has been estimated that the amount of e-waste being generated may increase by up to 500% over the next decade.
This situation is exacerbated by the trend of adding even more functions to electronics. The heart of all of these devices is the printed circuit board (PCB). Multiple tracks interconnect various electronic components that have been permanently positioned on the board using tin-containing and possibly leaded solder. Furthermore, because many devices require more than one PCB, multiple cables and connectors are required to interconnect the PCB's. As the number of connections increases, it becomes necessary to include components whose sole purpose is to encode, transmit and decode various types of information. Increasing the amount of hardware and data that must be processed, eventually slows the operation of the device. Manufacturers have responded by increasing speed, which requires additional energy, larger and more powerful batteries, and so on. This escalates the e-waste.
Efficiently functioning electronics require that components are securely and permanently fastened to the PCB, preventing the incursion of dust, dirt, and moisture, all of which interfere with electrical signals, by affecting the connections. The very nature of the electronics is to continuously advance, with improved components and increased functions. This makes it desirable for the consumer to discard the old electronics rather than repair or upgrade, even if only one of the components is faulty or out of date.
What is required is a way of integrating components that allows upgrading or replacement of faulty parts without the need for special instruments or tools. This requires a system that allows interconnection of various components and transmission of large amounts of information without dedicated wires and channels, multiple connectors, and tracks, allowing the consumer to move and change components at will. Such a system would decrease pollution, production costs and wasting of environmental resources while simultaneously decreasing cost and increasing convenience to the consumer. Decreasing wires and tracks would reduce inductive properties, giving such a device an increased level of resistance to natural and artificially generated electromagnetic shock fields.
The opinion of engineers today seems to be that such a thing cannot be done. According to one, “ . . . to make all the integrated circuits properly talk to each other while dealing with the electromagnetic conductance issues; metal cages around components, thousands of signal paths of multiple layers of the PCB, packing signal lines between power planes, running signal lines in zigzags to produce equidistant signal paths . . . ” is not feasible. Another has stated, “A CPU needs to be incredibly reliant on connections (that's why they are soldered in). We do live in a world of millions of never going to happens . . . most of these things never happen because of the fact that they can't be done.”
Many companies and research institutions are searching for a technology that allows the free interchange of components, reduces production costs, reduces waste, while increasing the speeds, power, and efficiency of electrical devices.
Patents have been granted on conductive glass and transmission of data by light energy. Motorola and Google are working on a cooperative project attempting to build a modular phone. No one has come up with a system that addresses the above noted issues. The present invention does.
SUMMARY OF THE INVENTION
The present invention is directed to a photoelectric conductive motherboard with photoelectric modules. The board has multiple layers for conducting electricity to provide power for the individual modules and concurrently propagating modulated light, allowing the connected modules to communicate. Integrated arrays of emitters and receivers are paired by wavelength and intensity. Multiple module pairs use the same light conductive layer on the motherboard without mutual interference. Information is carried between the modules simultaneously at high speeds.
BRIEF DESCRIPTION OF THE DRAWINGS
The exact nature of this invention, as well as the objects and advantages thereof, will become readily apparent upon consideration of the following specification in conjunction with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof and wherein:
FIG. 1 is a front view of the photoelectric conductive motherboard, showing light and sound modules in place;
FIG. 2 is a cross-section of the motherboard of FIG. 1 ;
FIG. 3 is a front view of the motherboard showing the multilayer composition;
FIG. 4 is a cross-section of the motherboard of FIG. 3 ;
FIG. 5 is a cross-section of the motherboard connected to a power source;
FIG. 5A is an illustration of the motherboard connected to multiple light transmitting modules;
FIG. 6 is a cross-section schematic illustration of the motherboard transmitting different light waves;
FIG. 7 is a detailed illustration of an emitter and a receiver pair, each with their respective filters;
FIG. 8 is a cross-section of the motherboard connected to a light switch module;
FIG. 9 is a top view of the motherboard showing a cross-section of the light switch module of FIG. 8 ;
FIG. 10 is a cross-section of the motherboard connected to an LED light module;
FIG. 11 is a front view of the motherboard with a cross-section of the LED light module;
FIG. 12 is a cross-section of the motherboard connected to an audio input module;
FIG. 13 is a front view of the motherboard with a cross-section of the audio input module storing fast switching electronic components (semiconductors) connected to the electrical input and light emitters;
FIG. 14 is a cross-section of the motherboard connected to an audio output module;
FIG. 15 is a top view of the motherboard with a cross-section of the audio output module;
FIG. 16 is a cross-section of the motherboard illustrating the operation of the motherboard;
FIG. 17 is a cross-section of the motherboard illustrating the operation of the motherboard; and
FIG. 18 is a cross-section of the motherboard illustrating the operation of the motherboard.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the front external surface of the photoelectric conductive motherboard 11 and modular system, is shown in FIGS. 1 and 2 . The modules 13 , 15 , 17 and 19 are in direct contact with the outer layers of the transparent photoelectric conductive layered board 11 . It is important to note that these components, whether a light switch 15 , a multicolor light diode 13 , audio input 17 , or audio output 19 , can be placed virtually anywhere on the board 11 and still function at full capacity. They are able to both receive power and communicate.
FIGS. 3 and 4 detail the various layers of the photoelectric board 11 , both as viewed from the top and in cross section. The outermost layers 21 , 23 are constructed of electrically and photo conductive, partially light reflective, transparent glass, polymers, or similar material. These layers also serve as electrical conductors to supply power to the attached modules. The central layer 25 is a photoconductive layer, efficiently and evenly propagating and partially diffusing the light evenly throughout the entire board 11 . Sandwiched between the electrically and photo conductive layers 21 , 23 and the photoconductive layer 25 are nonelectrically conductive, photo conductive layers 27 , 29 that prevent shorts that would occur should power be conducted between the top layer 21 and bottom layer 23 .
Power can be supplied to the photoelectric motherboard in multiple ways. The preferred method is shown in FIGS. 5, 5A . An electric power source module 31 having a nonconductive housing contains a set of conductive tracks 87 , 89 . The tracks are connected to power source wires 37 . The track 87 connects power to the positive electroconductive layer 23 . The track 89 connects power to the negative layer 21 . When the power module is in place, power is transferred by the tracks 89 , 87 to the entire surface of the electrically conductive layers 21 , 23 . Any modules connecting to any place or point on these two surfaces 21 , 23 on the motherboard 11 are energized.
The photocommunication between modules through the motherboard 11 is illustrated in FIG. 6 . Transmitter/receiver modules 39 , 41 placed on the photo and electrically conductive surface of the motherboard 11 allow for simultaneous creation of multiple light channels 43 , 45 , 46 that transfer and receive data through the photoconductive layers shown in FIG. 4 . Referring to FIG. 5 , the light sources 39 (diodes in the preferred embodiment) and receivers 41 emit and detect, respectively, different and specifically preset types of light waves 43 , 45 , 47 so that there is no interference between signals. This may be achieved by coating the emitters 39 and receivers 41 with a particular light filter 49 , 51 so that they are perfectly paired. Alternatively, the light may be segregated by frequency. Visible and infrared receivers and transmitters could be utilized. For example, to preprogram and create multiple channels and allow for an increased amount of data to be transmitted simultaneously, a multicolor LCD (not shown) can be used. As the color of the LCD is varied, the frequency of the light waves emitted and received are altered, allowing components to be paired or turned in real time. It also makes it possible to group or remove components at will without physically or mechanically altering them. Each selected frequency range for the LCD emitted light waves, serves as a separate data channel. This allows for multiple channels to be easily created.
FIGS. 8 and 9 are an illustration of the preferred embodiment of the photoelectric conductive motherboard 11 connected to a light switch module 53 . The module, shown as attached to an end of the motherboard 11 , comprises a nonelectrically conductive housing 55 that contains an imbedded infrared light emitting diode 57 and a visible light emitting diode 59 . The negative legs of both diodes are directly grounded via an electroconductive track 89 to the negative electroconductive plate 21 . The positive legs of the light emitters are indirectly attached via wires to a three way switch 61 that is also connected to a positive track 87 that is in contact with the positive electroconductive plate 23 . Note that the module lies in contact with the outer layers of the motherboard and derives power from it. The diode can transmit light through all the layers and to all components attached to the motherboard.
In the preferred embodiment, this light switch module 53 is paired with a bicolor light module 67 ( FIGS. 10 and 11 ) that is similar in design and concept to the switch module, but distinct in that the light emitters have been replaced with receivers, light detecting diodes 69 , 73 that detect visible and infrared light, respectively. In this module, the three way switch has been replaced with a bicolor green and red LED 75 . The negative terminal of the multicolor light LED 75 is indirectly connected to a negative electroconductive track 89 and plate 21 via the infrared and visible light detecting diodes. The positive terminal is directly connected to the positive plate 23 via a positive track 87 and a common positive wire 77 connecting the track to the diode.
No matter where the light switch module 53 and the multicolor light module 67 are placed on the photoelectric conductive motherboard 11 ( FIG. 8 ), it is possible to selectively manipulate which colors the LED 75 displays without physically interconnecting the three way switch 53 and multicolor LED 75 ( FIG. 10 ) by wires or tracks. This light communication can be used to transmit data on several channels simultaneously, even extending to information encoded as video and sound, as will be described hereinafter.
FIGS. 12 and 13 show an audio input module 79 , which is similar in terms of design to the above described modules. However, it has modifications that allow it to work with the photoelectric conductive motherboard 11 . In this embodiment, an audio input signal is fed via headphone jacks 81 into two fast switching semiconductor components 83 . These semiconductors are individually connected to light emitting diodes 85 . One fast switching component is directly and permanently connected to the positive photo and electrically conductive plate 23 via a positive track 87 and the positive leg of the light emitting diode. The negative leg of the diode is connected to the ground by way of the track and the photo and electrically conductive plate. The other fast switching component is directly connected to the negative photo and electrically conductive plate by the negative track 89 and the negative leg of the diode. That is, the audio input module has a set of preset light emitters that are connected to their power supply via one of their poles individually via a semiconductor. In order for them to complete their circuit and receive the missing positive or negative power, they rely on the paired semiconductors to become excited and conductive by the low voltage audio signal input, which will be positive or negative depending on the type of semiconductor (PNP or NPN).
The audio input module 79 is paired with an audio output module 91 shown in FIGS. 14 and 15 . The audio output module 91 is constructed in the same basic manner as the above described modules, with the following modifications. The positive and negative poles of a specific set of light receivers 93 and 95 are permanently attached to the positive or negative track 87 , 89 , which is in contact with the photo and electrically conductive power plate, respectively. The other pole of these light receivers 93 , 95 is attached to the matching pole of an amplifier 97 that receives its power from tracks adjacent to and in contact with the positive 23 or negative 21 plates of the board 11 . A set of wires attached to the amplifier's positive and negative output permanently connects to a speaker 99 . As the audio input module's emitters produce light of specific wavelengths and intensity, the light propagates through the photo and electrically conductive layer of the entire board until it excites the specific receivers 93 , 95 of the audio output module 91 , making the output module 91 more conductive. In this way, variable amounts of voltage, based on the wavelength and intensity of the light, are allowed to input into the positive and negative channel inputs of the amplifier 97 that is simultaneously powered by the positive 87 and negative 89 track that are in contact with the board 11 . As a result, an amplified sound signal is outputted by the positive and negative outputs of the amplifier module 91 and by wires, powers the speaker 99 to produce sound.
These sound modules show how some semiconductor components utilized in current technologies can easily be modified to be used with and powered by the photoelectric conductive motherboard. A working prototype has been produced. The prototype shows that the photoelectric conductive motherboard can handle multiple channels of data simultaneously, without interference, regardless of the originating form, whether light, sound or video.
The operation of the photo and electrically conductive motherboard 11 and some modules can be seen in FIGS. 16, 17 and 18 . The three positions of the switch 61 are as shown on the left in FIGS. 16, 17, and 18 .
In FIG. 16 , the switch 61 is in neutral position, no light is emitted, no signal is sent, and the emitter LED 57 does not light.
In FIG. 17 , the switch is pushed to the left and the visible light circuit is closed, causing the light source LED 57 to light up. The light from LED 57 is propagated through the conductive media 21 , 23 , 25 of the motherboard 11 and reaches the visible light sensitive receiver 69 . When this receiver is excited, the electric circuit on the green side of the multicolor diode 75 is closed and the diode produces green visible light.
In FIG. 18 , the switch 61 is pushed to the right. This causes an infrared diode 59 to light up, the light is propagated throughout the motherboard 11 to a paired infrared receiver 73 , closing a circuit that causes the multicolor LED 75 to produce red light.
The photoelectric conductive motherboard can interconnect various components without soldering, cables, sockets, and so on. The motherboard facilitates an infinite number of combinations of components or modules to be placed together on the board for power and communication. This allows new levels of customization, increasing the numbers of types of devices that can be produced. Almost no copper is used in construction, leading to a device with a very low coefficient of conductance. The photoelectric conducting motherboard can use currently available electrical components including, but not limited to semiconductors, such as microprocessors and amplifiers, by simply being paired with appropriate light emitter and receiver arrays.
The present invention is beneficial for many reasons. First, it allows a user without special skills and equipment to add or replace any module or component desired. And since the emitting modules can only communicate with the receiving modules that detect their specific wavelength or intensity of light, it is possible for multiple light channels to be created and various types of information to be propagated at the same time, interconnecting all of the components. This results in a system of extraordinary power quality and utility. For example, if a user would like to build a cell phone, all that is necessary is to place the modified core components (processor, microphone, antenna, speaker, etc.) anywhere onto the board and it will function, that is, power-up and communication. If repair, upgrade or just customization is desired, the user can simply replace or add the modules of choice.
Another benefit of the invention is that it can work together with existing technology. All that is required is to pair the inputs and outputs of the various currently-available semiconductors, such as processors with preset light emitters and receivers, essentially resulting in the data from the processors being inputted and outputted in terms of light instead of the usual electrical impulse connections. Current technology's micro circuitry is not wasted, since only minor modification is needed for it to be integrated with the invention.
An obvious advantage of above is an inevitable immediate reduction in e-waste, both in terms of toxins generated during manufacture and in terms of discarded electronics. Since this invention can consist of a type of conductive glass, it does not require the use of the same quantities of precious metals as are utilized in current electronic construction. Bigger batteries with greater capabilities, as are required for increased speeds when many components must communicate quickly, will also become unnecessary. The invention communicates at the speed of light. Because the components are entirely replaceable, the user can replace faulty components, upgrade the device at will, and customize as desired. There will be no more need to discard functional electrical equipment because of the failure of one part. One can just replace the part or even repurpose the entire device for another use. Turning your modular cell phone into a router, for example, would be simple.
Because communication is between modules is established by the use of light instead of multiple tracks and wires, the chance of failure due to environmental factors is negligible. Water will not be able to render the device inoperable by shorting out tracks since, as soon as the device is dry, operation will resume. The device is also more resistant than conventional motherboards to high temperatures, which usually cause increasing resistance within the tracks, eventually decreasing speed and efficiency. In comparison, communication via light is not affected by temperature.
The foregoing description of a preferred embodiment of the invention was presented for illustration and description. It was not intended to limit the invention to a precise form. Those skilled in the art will understand how to best utilize the invention in various embodiments and various modifications as best suited to the use contemplated. The scope of the invention should not be limited by the specification, but defined by the following claims. | A photoelectric conductive motherboard with electronic modules. The multilayer board conducts electricity to provide power for the individual modules, and concurrently propagates light allowing the modules to communicate with each other by an integrated array of light emitters and receivers that are paired by wavelength and intensity. Large amounts of information can be transmitted between the modules simultaneously, at extremely high speeds, without the need for additional hardware. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a powder catalyst supply apparatus and a catalyst supply system and, more particularly, to a powder catalyst supply apparatus and a catalyst supply system which are suitable for olefin gas phase polymerization reaction.
2. Related Background Art
In an apparatus for manufacturing a polyolefin by using an olefin gas phase polymerization reaction vessel, a powder catalyst must be supplied to the reaction vessel. It is preferable that this powder catalyst be continuously supplied. In reality, however, there is no apparatus that can continuously and constantly supply granulated powder particles into a gas phase polymerization reaction vessel at a high pressure. As disclosed in Japanese Patent Publication No. 49-17426 and Japanese Patent Laid-Open No. 60-227824, a batch metering/supplying system is generally employed, in which a catalyst is metered by a metering pipe, and is supplied by using an inert gas as a carrier gas. An example of the batch metering/supplying system will be described below with reference to FIG. 1.
A powder catalyst is supplied from a catalyst storage hopper 2 to a gas phase polymerization reaction vessel 1 by using an olefin gas or an inert gas as a carrier gas, and a polymerization reaction is caused, thereby manufacturing a polyolefin. In this catalyst supply method, in order to prevent solidification of powder particles, which is caused when an olefin gas enters the catalyst storage hopper 2, a batch supply system using a metering pipe 3 is employed. More specifically, a valve 8 is opened while the valves 4, 5, and 6 are closed, so as to fill a volume tank 7 with an inert gas which does not contribute to a reaction. Thereafter, the valve 8 is closed, and the valve 4 is opened to inject a catalyst from the catalyst storage hopper 2 into the metering pipe 3. The valve 4 is then closed, and the valves 5 and 6 are opened to supply the catalyst in the metering pipe 3 into a catalyst supply pipe 9, by using a pressurized gas from the volume tank 7. The catalyst supplied to the catalyst supply pipe 9 is supplied to the gas phase polymerization reaction vessel 1 together with the olefin gas flowing in the catalyst supply pipe 9. By repeating this operation, entrance of the olefin gas into the catalyst storage hopper 2 can be prevented, and the catalyst can be supplied to the gas phase polymerization reaction vessel 1 at a high pressure. In the gas phase polymerization reaction vessel 1, the supplied catalyst speeds up a polymerization reaction, thus manufacturing a polyolefin.
In addition, Japanese Patent Publication No. 53-8666 discloses an apparatus which is constituted by a metering means having a rotating shaft member and is designed to inject granular particles into a reaction chamber. In this apparatus, granular particles are supplied from the metering means to the reaction chamber through a capillary tube having an inner diameter of 0.76 to 3.2 mm. For this reason, when granular particles are to be supplied in a large amount, the capillary tube may clog up, and hence it is difficult to stably supply granular particles to a reaction vessel of an industrial scale.
In the conventional system, although entrance of an olefin gas into the catalyst storage hopper 2 and solidification of a catalyst upon polymerization can be prevented, the catalyst is intermittently supplied from the catalyst storage hopper 2 to the catalyst supply pipe 9. For this reason, the catalyst is intermittently supplied to the gas phase polymerization reaction vessel 1 to interfere with uniform distribution of the catalyst in the gas phase polymerization reaction vessel 1. As a result, a dense catalytic portion is formed to generate a lump upon local polymerization, and a mixing failure is caused in the reaction vessel 1, increasing the possibility of clogging up the reaction vessel 1. In addition, the manufacture of uniform products is adversely affected. It is considered that the period at which the catalyst is intermittently supplied may be shortened by reducing the capacity of the metering pipe 3. In this case, however, the frequency of opening/closing operations of the valves is increased to shorten the service life of the apparatus.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a powder catalyst supply apparatus and a catalyst supply system which minimize the amount of an inert gas to be supplied, when a powder catalyst is to be supplied to a gas phase polymerization reaction vessel, and prevent generation of a lump caused by nonuniform distribution of the catalyst in the reaction vessel, thereby manufacturing a polyolefin of uniform quality with continuous supply of the catalyst.
A continuous powder catalyst supply apparatus of the present invention is characterized by comprising catalyst storage means having a catalyst inlet port formed in an upper portion thereof and a catalyst supply port formed in a bottom surface thereof to supply a catalyst by free fall, catalyst supply means, formed in the catalyst storage means, for substantially continuously supplying the catalyst to the catalyst supply port, and forcible discharge means for forcibly discharging the catalyst, supplied from the catalyst supply means to the catalyst supply port, through the catalyst supply port with a pressurized gas.
In addition, a catalyst supply system of the present invention is characterized by comprising the continuous powder catalyst supply apparatus, a gas phase polymerization reaction vessel, and an ejector, having a suction port connected to the catalyst supply port, an olefin gas exhaust port connected to the gas phase polymerization reaction vessel, and an inlet port for receiving an olefin gas, for generating a negative pressure in the suction port by supplying the olefin gas, drawing the catalyst through the catalyst supply port of the continuous powder catalyst supply apparatus, and supplying the catalyst into the gas phase polymerization reaction vessel together with the olefin gas.
According to the continuous powder catalyst supply apparatus of the present invention, with the above-described arrangement, the catalyst supplied from the catalyst supply port formed in the polymerization reaction catalyst storage means by free fall can be reliably discharged, and the catalyst can be substantially continuously supplied to a gas phase polymerization reaction vessel.
In addition, although a large amount of inert gas in the gas phase polymerization reaction vessel is inhibited from being supplied to the catalyst supply port, the inert gas constantly flows within an allowable range of amounts. Therefore, the catalyst metered by the continuous catalyst supply apparatus is forcibly discharged to the catalyst suction port of an ejector by free fall due to its own weight and by the inert gas. The amount of inert gas which does not contribute to a polymerization reaction can be reduced by the forcible discharge means based on this inert gas and by the effect of the ejector.
Furthermore, in the catalyst supply system of the present invention, a suction means constituted by an ejector is arranged at the supply port of a catalyst supply apparatus, and an olefin gas is supplied to a gas phase polymerization vessel through the ejector so as to draw a catalyst with a suction force generated by the ejector, thereby supplying the catalyst to the gas phase polymerization reaction vessel intrained with the olefin gas.
With the functions of the inert gas and the ejector described above, the olefin gas does not flow back to the catalyst supply apparatus unless the piping between the ejector and the gas phase polymerization reaction chamber clogs up. Therefore, a polymerization reaction in the catalyst supply apparatus can be prevented, and clogging due to the formation of a polymer can be prevented, thereby allowing stable supply of the catalyst.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not to be considered as limiting the present invention.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art form this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view showing the schematic arrangement of a conventional catalyst supply system;
FIG. 2 is a view showing the schematic arrangement of a catalyst supply system according to an embodiment of the present invention;
FIG. 3 is a view showing the sectional structure of a continuous powder catalyst supply apparatus in the catalyst system in FIG. 2;
FIG. 4 is a plan view of a rotary disk of the continuous catalyst supply apparatus in FIG. 3; and
FIG. 5 is a view showing the sectional structure of a metering through hole of the rotary disk of the continuous catalyst supply apparatus in FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 2 shows the schematic arrangement of a catalyst supply system of the present invention. This catalyst supply system comprises a hopper 10 for storing a catalyst for a polymerization reaction, a continuous catalyst supply apparatus 20 for receiving the catalyst from the hopper 10 and continuously supplying the catalyst, a gas phase polymerization reaction vessel 30, and a material gas source 40 for supplying an olefin gas as a material gas for a polymerization reaction, or an inert gas. A valve 11 is arranged at a supply port 10a of the hopper 10 so that the supply of the catalyst to the continuous catalyst supply apparatus 20 can be adjusted by operating the valve 11. In addition, a pressure equalizer 12 is arranged to adjust the pressure differences between the continuous catalyst supply apparatus 20, the hopper 10, and the outlet line of the continuous catalyst supply apparatus 20, thus allowing smooth supply of the catalyst from the hopper 10. The continuous catalyst supply apparatus 20 has a motor 21. A driving shaft 21a of the motor 21 is designed to drive a rotary disk 22 in the continuous catalyst supply apparatus 20 through a belt 21b and a pulley 21c. The material gas source 40 and the gas phase polymerization reaction vessel 30 are connected to each other through an ejector 50. A suction port 51 of the ejector 50 is connected to a catalyst supply port 23 of the continuous catalyst supply apparatus 20 through a shut-off valve 60. A material gas supply port 52 of the ejector 50 is connected to the material gas source 40 through a flow rate adjusting unit 41. A material gas exhaust port 53 of the ejector 50 is connected to the gas phase polymerization reaction vessel 30. The ejector 50 generates a negative pressure, corresponding to the flow rate of the material gas, in the suction port 51, so that the catalyst drawn through the suction port 51 is supplied from the exhaust port 53 into the gas phase polymerization reaction vessel 30 together with the material gas.
A gas source 70 for supplying an inert gas such as nitrogen gas is connected to the continuous catalyst supply apparatus 20 through a flow rate adjusting unit 71. In addition, a differential pressure gauge 54 is arranged between the material gas exhaust port 53 and the suction port 51 of the ejector 50 to measure the pressure difference therebetween. With this arrangement, a monitoring operation can be performed to prevent a material gas, supplied through the material gas supply port 52, from entering the suction port 51.
FIG. 3 shows the sectional structure of the continuous catalyst supply apparatus 20. The continuous catalyst supply apparatus 20 is constituted by a base portion 23 and a cylindrical surrounding wall 24 fixed to the base portion 23. A through hole 25a is formed in the base portion 23. A driving shaft 25 rotated by the motor 21 is inserted through the through hole 25a. The driving shaft 25 is rotatably supported by bearings and a seal member 25b disposed in the through hole 25a. The rotary disk 22 is fixed to the distal end portion of the driving shaft 25 so as to be rotated by the driving shaft 25. A conical cap 26 is fixed on the rotary disk 22. The vertex of the conical distal end of the conical cap 26 is located on the line extending along the center of rotation of the driving shaft 25. With this conical cap 26, the catalyst supplied from the hopper 10 located above the continuous catalyst supply apparatus 20 can smoothly flow around the rotary disk 22.
A catalyst supply through hole 23a is formed in the outer peripheral portion of the base portion 23. A connection pipe and a flange 27 are connected to the lower surface of the base portion 23 at the catalyst supply through hole 23a. As shown in FIG. 4, metering through holes 28, each having a circular shape and a predetermined size, are concentrically formed in the peripheral portion of the rotary disk 22 at equal angular intervals. The position of each metering through hole 28 with respect to the center of rotation is selected such that each metering through hole 28 accurately passes over the catalyst supply through hole 23a while the rotary disk 22 is rotated. In addition, as shown in FIG. 5, the diameter of each metering through hole 28 gradually increases toward the bottom, and an inclination angle θ of the wall of the hole is set to be slightly larger than the angle of repose. In this case, the angle of repose means the maximum angle, defined between a surface layer of granulated powder particles and the horizontal plane, at which the surface layer can be kept stationary by the friction between the particles. More specifically, it means the angle between the horizontal plane and the generating line or inclined surface of a cone formed when granulated powder particles are caused to continuously fall through a small hole or a gap to be deposited on a flat surface (Takeshi Karino, "Powder Transportation Technique", Nikkan Kogyo Shinbun-sha, p. 32). By setting the inclination angle θ to be slightly larger than the angle of repose, residence of granular particles and clogging of each hole 28 can be prevented. Furthermore, if a conductive resin is coated on the entire surface of the rotary disk 22 including the metering through holes 28, or the rotary disk 22 is impregnated with a fluorine-containing resin, slipperiness can be improved. By adding this effect to the above-described effect of the angle of repose, residence of granular particles in the respective metering through holes and clogging thereof can be prevented more effectively.
With this arrangement, the catalyst continuously falls from the metering through holes 28, and hence substantially continuous supply of the catalyst can be realized.
In addition, a pressurized gas supply chamber 29 shown in FIG. 3 is formed on a portion of the surrounding wall 24 of the continuous catalyst supply apparatus 20. The lower surface of the pressurized gas supply chamber 29 is located slightly above the surface of each metering through hole 28 of the rotary disk 22 so that the catalyst on the rotary disk 22 which is carried upon rotation of the rotary disk 22 is leveled by the edge of the lower surface of the chamber 29. Therefore, only the catalyst existing in each metering through hole 28 is substantially conveyed to a position below the pressurized gas supply chamber 29. A pressurized gas exhaust port 29a is formed in a bottom surface portion of the pressurized gas supply chamber 29. In addition, a pressurized gas supply port 29b for supplying a pressurized gas to the pressurized gas supply chamber 29 is formed in the surrounding wall 24 which constitutes a portion of the pressurized gas supply chamber 29.
An operation of the catalyst supply system of the embodiment will be described next with reference to FIG. 2.
When the valve 11 is opened, a predetermined amount of catalyst is supplied from the hopper 10 to the continuous catalyst supply apparatus 20. Since the hopper 10, the continuous catalyst supply apparatus 20, and the outlet side of the continuous catalyst supply apparatus 20 are kept at an equal pressure by the pressure equalizer 12, the catalyst can be smoothly supplied. When the supply of the catalyst is completed, the valve 11 is closed. The motor 21 is then driven to rotate the rotary disk 22. At the same time, the flow rate adjusting unit is adjusted to supply a predetermined amount of inert gas from the inert gas source 70 into the pressurized gas supply chamber 29 through the pressurized gas supply port 29b.
In the continuous catalyst supply apparatus 20, the catalyst supplied from the hopper 10 flows along the peripheral portion of the rotary disk 22. The catalyst then flows into each metering through hole 28 and is conveyed upon rotation of the rotary disk 22. A portion of the catalyst stacked above the upper surface of the rotary disk 22 at the metering through hole 28 is leveled by a side surface 29d of the pressurized gas supply chamber 29 in FIG. 4. As a result, only the catalyst existing in the metering through hole 28 is conveyed to the position below the bottom surface of the pressurized gas supply chamber 29. The conveyed catalyst in the metering through hole 28 falls from the catalyst supply through hole 23a by free fall when the metering through hole 28 overlaps the catalyst supply through hole 23a. Since the diameter of each metering through hole 28 increases toward the bottom, and the inclination angle θ is set to be slightly larger than the angle of repose, the possibility of residence of granular particles in the hole 28 and clogging thereof is low in this free fall of the catalyst. In addition, since the entire surface of the rotary disk including the metering holes is coated with a conductive resin or the rotary disk is impregnated with a fluoroplastic material, free fall of the granular particles is smoothly performed. Furthermore, the granular particles are caused to fall more reliably by a pressurized gas jetting out from the pressurized gas exhaust port 29a of the pressurized gas supply chamber 29. Moreover, by supplying such a pressurized gas into the catalyst supply through hole 23a, entrance of a material gas through the catalyst supply through hole 23a can be prevented, thus preventing the catalyst and the material gas from coming into contact with each other in the continuous catalyst supply apparatus 20.
Since the metering through holes 28 are formed in the rotary disk 22 at equal angular intervals, the catalyst can be supplied, in a predetermined amount, intermittently but almost continuously in effect.
The catalyst supplied through the catalyst supply through hole 23a is supplied to the ejector 50 through the shut-off valve 60. A negative pressure is generated in the suction port 51 of the ejector 50 upon flowing of the material gas through the material gas supply port 52. Owing to this negative pressure, the catalyst supplied from the continuous catalyst supply apparatus 20 is drawn and is discharged through the material gas exhaust port 53 together with the material gas so as to be supplied to the gas phase polymerization reaction vessel 30. By using the ejector in this manner, the amount of inert gas required to supply a catalyst to the gas phase polymerization reaction vessel in the conventional system can be reduced. In addition, since the negative pressure is used, substantially continuous supply of the catalyst can be performed while the contact of the material gas with the catalyst in the supply system is prevented. Furthermore, the pressure difference between the suction port 51 and the material gas exhaust port 53 is always monitored by the differential pressure gauge 54. Therefore, when the material gas flows back from the suction port 51 for some reason, e.g., clogging of the pipe for supplying the material gas to the gas phase polymerization reaction vessel 30, the shut-off valve 60 is immediately closed to prevent the material gas from flowing back to the continuous catalyst supply apparatus 20.
In the embodiment, each metering through hole is tapered. However, the shape of each hole can be arbitrarily changed. If the number of metering through holes is increased, and they are formed at smaller intervals, substantially continuous supply of a catalyst can be realized.
In addition, by using a variable-speed motor to rotate the rotary disk, continuous changes in the amount of a catalyst supplied can be easily made.
Note that a detector for detecting the flow rate of a powder catalyst may be arranged between the shut-off valve 60 and the ejector 50 to monitor the powder catalyst.
In the embodiment, the continuous powder catalyst supply apparatus and the catalyst supply system are associated with the manufacture of a polyolefin. However, the present invention is not limited to this but can be widely applied as an apparatus for continuously and constantly supplying granulated powder particles to a pressurizing system.
In the embodiment, the powder supply system has a single supply port. However, the system may have a plurality of supply ports. In this case, the amount of catalyst supplied to the gas phase polymerization vessel can be increased without increasing the rotational speed of the motor.
By employing the continuous powder catalyst supply apparatus and catalyst supply system of the present invention, uniform distribution of a catalyst in a gas phase polymerization reaction vessel can be realized, and the formation of a lump can be prevented. In addition, a uniform, high-quality polyolefin can be manufactured.
From the invention thus described, it will be obvious that the invention may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | A continuous powder catalyst supply apparatus and a catalyst supply system that is suitable for olefin gas phase polymerization. The supply apparatus comprises a catalyst storage chamber having a catalyst inlet port and a catalyst supply port for transmitting the catalyst to the reactor. Inside the catalyst storage chamber is a catalyst supply mechanism which substantially continuously supplies the catalyst to the catalyst supply port, and a forcible discharge mechanism which forcibly discharges the catalyst, supplied from the catalyst supply mechanism, through the catalyst supply port with a pressurized gas. The apparatus can be used to supply the catalyst to the reactor with low amounts of pressurized gas. Further, the system can be configured so as to avoid contamination of stored catalyst by reactant gas. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to long bulk conveyors and to the cooperative combination of flexibly shiftable belt conveyors and travelling shifting apparatus for lateral shifting of such conveyors by guided distributed travelling curvature, the shifting being to maintain convenient proximity to a progressive excavation of a bulk deposit such as lignite for convenient removal of the excavated bulk by the conveyor. More particularly, this invention relates to a belt conveyor comprising a framework comprising a flexible continuous rail or rails, a sequence of relatively rigid roller-carrier frames, and a set of pivotal, slidable, or rigid connections, the rails and frames being assembled by the connections into a flexibly continuous shiftable and accessible whole, the flexible continuity being largely due to the flexibility of the rails with the connections, and not largely due to the roller-carrier frames. This invention further relates to a travelling hoisting, shifting, and guiding vehicle with an adjustably curving rail-engaging guide roller array wherein the vehicle continuously powers and urges the guide array along the rails, and meanwhile powers, urges, holds, and adjusts the guide array in lateral and vertical position and in attitude, orientation, and curvature so as to shift the conveyor through a good distance by keeping the rails in controlled distributed travelling curvature. This invention also relates to an elongate guide carrier beam assembly for carrying a plurality of rail-engaging roller assemblies into linear and varyingly curvilinear engagement with the conveyor rail or rails, all for carrying and drawing the conveyor laterally by the rails while keeping the rails in safely controlled and guided distributed travelling curvature.
2. Description of the Prior Art
At a very early date in the development of open cast mining of lignite desposits it became apparent that sophisticated and heavy equipment would be necessary to remove the lignite in small chunks and pieces and transport it from the point of mining to a pick-up or storage location in economically feasible quantities. Since the mining apparatus which was developed to meet this goal is complex, bulky and heavy, and is designed to successively remove the lignite deposits farther and farther from the pick-up or storage location, it became necessary to develop successively longer conveyors for transporting the lignite to a point of loading or storage. These conveyor systems were designed in sections to facilitate periodic adjustment of the conveyor line to new positions closer to the lignite deposits. As the piecemeal-shiftable conveyor systems became more complex and greater in length, it became increasingly difficult to move the continuous conveyor sections from one location to another site which is closer to the point of mining of the lignite. Accordingly, special track lifting mechanisms were introduced into open cast lignite sites, and the weight of such apparatus has ranged up to 100 tons, and frequently had to be pulled by locomotives. This equipment was sometimes provided with traversing crawlers for quicker cross-travel between the conveyor lines which had to be shifted, and the cost of the conveyor-shifting operation became increasingly prohibitive as the conveyor lengths increased.
Perhaps the most widely used steerable, non-railbound, shifting device is a machine developed in 1953 by Rheinische Braunkohlen A.G., a German Company which introduced several innovations into the conveyor shifting procedure. A high shifting rate was achieved using the new apparatus, and the machine provided good maneuverability on rough and uneven terrain. Other advantages consisting of low maintenance and space requirements and independence of rail mounting, as well as reduced costs, were also realized. The steerable, non-railbound track shifting machine is small and compact, but requires the use of a bulldozer or tractor to provide the motive force required in the shifting technique. The German shifting apparatus includes a roller unit which is characterized by a welded casing fitted with two sets of rollers, one roller in each pair being fixed and the other pivotable on side arms, the pivotable roller designed to bias against the shiftable conveyor railbulb of one of the rails by an adjusting mechanism. Buffer springs in the apparatus serve to compensate for unequal rail head dimensions, and the device is provided with arms for connection to the tractor or bulldozer. The tractor must be provided with a side boom, which is attached to the top of the shifting apparatus after the apparatus is connected to one of the rails of the shiftable conveyor. The side arms extending from the roller unit are supported against one side of the tractor. The roller unit is designed to traverse one rail of the shiftable conveyor as the tractor is driven forward and at an angle with respect to the shiftable conveyor line. When the roller unit of the shifting apparatus is mounted on one of the rails of the shiftable conveyor, the roller with the rail attached is then raised by the boom mounted on the tractor, until one end of the track sleepers is clear of the ground. The tractor is then moved forward along the conveyor, pulling the conveyor sections in the shiftable conveyor into sequential alignment from a first linear position to a second linear position closer to the lignite deposits. If sliding of the tractor occurs, during the shifting or realignment process the tractor must be steered at a slight angle away from the conveyor string in order to provide the proper tractive force and direction to realign the conveyor sections. The distance over which the rail is drawn sideways in one passage is sometimes called a "shifting step", and is represented to be up to two meters on dry and level ground. However, in the first passage, the designers of the German shifting apparatus recommend that the rail and sleepers be loosened from the original linear position, particularly in the case of frozen ground, and the second pass is then utilized to actually displace the conveyor sections from one position to the other. The designers further emphasize that the successive shifting steps ought to be small, rather than large, in order to minimize damage to the rail and the tractor and to achieve a fair tractor travel speed. Counterweights must also be used on the tractor, especially when the ground is soft, in order to better regulate traction.
In the steerable, non-railbound, German shifting machine, great stress is placed on the shiftable conveyor rail resulting from the shifting, lifting and forward motion of the tractor, to great disadvantage. For shiftable conveyor rails with wider rail gauges, the stress and load increases considerably, particularly if the module sleepers must be pulled from a clay or loam base, which sometimes create a suction effect. Such high loads and stresses frequently cause damage to the conveyor rail, and in many cases require replacement of the rail due to severe rail distortion, which prevents subsequent traversal of the rail by the roller unit of the shifting apparatus. Furthermore, the shifting procedure using this equipment is slow and requires multiple passes in order to be effective, particular under circumstances where the lateral displacement of the shiftable conveyor must be extensive.
Many disadvantages are found in the side-boom tractor with two roller pairs as found in the prior art. Firstly, the lateral force on the rail must be of the same order of magnitude as the vertical force, or even exceed it, since the coefficient of sliding friction between the sleepers and the ground will certainly sometimes exceed 1, and the shifting is obtained by dragging one end of the nearby sleepers or cross-ties across the ground, and both ends of some nearby ones. This by itself is very hard on the rails and connections, but this drag has the additional penalties next discussed. Secondly, the offset resulting from any s-shaped or reflex curve in a structural member depends largely on two causes, namely the curvature, and the length over which the curvature is obtained. As is well known in structural mechanics, bending stress is directly proportional to curvature (i.e., inversely proportional to radius of curvature), and since stress is limited by consideration of the material to some allowable stress, then curvature is likewise limited to some peak allowable. It is therefore desirable to have the peak value obtain over a length. But in the prior art, the curvature will be maximum nowhere but within the roller assembly, and the drag forces aforementioned will diminish the length of curvature obtained, thereby diminishing the shifting step. Thirdly, there being only two roller points, and, two points being insufficient to define a curve, the curvature is not defined nor limited by the design of the machine, but rather by the actions of the operator as governed by information, judgement, and attention, which may vary, unfortunately. Fourthly, since the drag forces are suddenly and unpredictably variable, with only the two roller pairs lifting only one side of the conveyor while dragging the other and while breaking adhesion of the ties to the ground, the maximum offset safely obtainable is likewise unpredictable. There might be some safe limit, but since the limit would only occasionally apply, the temptation would build to take too long a step, and then to cause damage. Fifthly, the lifting of one side of the conveyor while dragging the conveyor introduces torsional stresses into the rails; such stresses are simultaneous with the stresses due to lateral curvature, and must be reckoned into the total and thus reduce the allowable lateral curvature. These stresses also tend to break the connections between the rails and the roller-carrier frames. Sixthly, the lifting effects are maximum at precisely the point where the lateral bending and torsional effects are maximum, and therefore further limit the lateral curvature allowable.
These and other disadvantages of the side-boom apparatus of the prior art find expression in frequent breaking of the rails and connections, and in long periods of down-time during conveyor shifts. More detailed discussion and structural analysis of such shifting structures will further illuminate the prior art, and serve to illuminate this invention as well, and such discussion follows.
In the lateral shifting of flexibly shiftable conveyors, it is necessary to bring a travelling interval of the conveyor into a travelling s-shaped or reflex curve, or into some approximation of such a curve. Analysis and understanding of such structures and their deflection curves is usually best accomplished by a progression of idealizations from a first simplest idealization to other more complicated and accurate approximations such as follow.
For a first illumination and a first approximation, consider some conveyor framework as if it were an initially straight beam brought into horizontal bending; such idealizations are sometimes usefully applied to triangulated trusses using the moment of inertia of the chords alone in beam-theory to approximate stresses, then using the rule-of-thumb that calculation will underestimate deflections by 15%, more or less. Such calculation will show that no useful flexible shifting can be obtained in fully triangulated structures of such proportions as are found in strip mining, since even a hundred tons of lateral force on the rails would defect such structures only a few inches, even with a hundred feet of curvature. Such forces and lengths would destroy the conveyor, rather than bring it into useful curvature. This is, of course, one of the reasons that such structures are not fully triangulated, but rather comprise triangulated panels and rectangular panels in alternating sequence. Nevertheless, useful insight can be obtained from the idealization, as follows. The idealization shows that deflection will depend on the magnitude of the curvature everywhere, not just at one point, and that the greatest offset is obtained in a given length by having the absolute value of the curvature be maximum everywhere. To have curvature be maximum everywhere is to have a pair of equal opposite tangent circular arcs, the radius of curvature for maximum safe offset being determined by the depth of the beam (i.e., the width of the conveyor) and the material of the beam, and only by those things. In the art, the material is rail steel, and the tolerable radius of curvature will be a thousand or so times the beam depth. Now, in the prior art here considered, the reflex curve is obtained by application of a shear at the end of the curve, so the curvature resulting varies linearly rather than remaining constant, i.e., the moment diagram is a pair of antisymmetrically disposed triangles, resembling a skewed bow tie. Engineer's beam theory will show the resultant deflection to be two-thirds of that obtained by the stepped rectangular diagram of constant (i.e. circular) positive and negative curvature; therefore the prior art method stresses the structure to a maximum while obtaining only about two-thirds of the maximum ideal or theoretical offset. The conclusion is tentative, pending a more refined model. The ideal for the beam-like truss is obtained by the application of three moments, a first one at the center of the reflex curve, and two others of opposite sense, each half the magniture of the first, at the two ends. Such a system is in equilibrium, and requires no imposition of shears whatever. No lateral force need be applied.
As a second and closer approximation to the shiftable conveyors of the prior art, it is useful to analyze the conveyor frame as approximately a Vierendeel frame in the horizontal plane, i.e. as a bending member having rails as the two chords and having the sequence of roller-carrier frames as the sequence of posts of the well-known Vierendeel frame, and having the four rail-to-frame connectors at the four corners of each frame as the moment connectors between posts and chords which characterize the Vierendeel frame. In such frames, overall shear is resisted by s-shaped or reflex bending of the chords between the posts, and such reflex bending is by far the largest contributor to the overall deflection in case the posts and moment connectors are stiff, and such is the case in the conveyors of the prior art. Seen otherwise, the principal deflections here are panel deflections or shear deflections; deflections due to overall flexure are a very small part of the whole. Therefore the maximum safe deflection in such conveyors is not found when the overall curvature approximates the s-shaped curve composed of two semicircles, but is obtained by having constant maximum panel shear, the overall curve approaching the cross-section of a terraced lawn of constant step height and constant step width, with the individual step-connecting slopes corresponding to the s-shaped curve of the first approximation. The overall average curvature during maximum safe deflection would approximate a ramp more than it would approach the two semicircles of the first approximation.
Even if a complete degree of rotary freedom were introduced into each of the four rail-to-frame connections at every roller-carrier frame (i.e., by making the connections pinned, rather than fixed as in the prior art), the action of the whole would still correspond to a Vierendeel frame with significant flexibility in the posts, since the points of entry of the rails into the post region would be slanted rather than level. The rails would be in curvature everywhere, with inflection points not only at the midpoints of the open shear panels, but also at the midpoints of the triangulated roller-carrier frames. The curve of the rails would then resemble a tilted corrugation, more than a sequence of terraces. The average overall curvature for maximum safe deflection would still approximate a ramp (albeit a corrugated ramp) more than it would approximate the two semicircles of the first overall approximation. However, the safe allowable deflection would be approximately doubled, as can be seen from strain-energy considerations, thus: Suppose, for simple example, that the open panels and triangulated panels were equal in width. Then the portion of the rails within the two types of panels would be equal in length and curvature, and would be twice that of the rails of the prior art, thus the strain energy will be twice as great, the maximum allowable rail curvature would have remained unchanged and, the shear unchanged. Therefore, the lateral load would be the same at lateral safe deflection, the external work must equal the strain energy and the lateral load must deflect twice as far.
OBJECTS OF THE INVENTION
Accordingly, it is an object of this invention to provide a new and improved shiftable belt conveyor wherein the rails are attached to the roller-carrier frames with a degree of freedom, thereby allowing an improved and greater safe shifting step.
Another object of this invention is to provide a new and improved shiftable belt conveyor wherein the rails are attached to the roller-carrier frames with a rotary degree of freedom, thereby allowing an improved and approximately doubled safe-shifting step.
Another object of this invention is to provide a new and improved shiftable belt conveyor wherein the rails have a sliding degree of freedom, thereby allowing the overall curvature of the conveyor to be arcuate, thereby providing a maximum shifting step.
Another object of this invention is to provide relief from stress concentration in conveyor rails by providing a degree of freedom in the connection of the rails to the roller-carrier frames.
Another object of this invention is to provide travelling spaced lifting and shifting machinery for conveyor lifting and shifting, so that stresses due to the one are not added to stresses to the other.
Another object of this invention is to provide travelling conveyor hoisting machinery for hoisting conveyors in translation without torsion, thereby avoiding stresses due to torsion of the conveyor rails and frame.
Another object of this invention is to provide conveyor hoisting and shifting machinery with means to hoist, shift, and lower a conveyor in separate travelling progression, thereby distributing and reducing various peak stresses, and thereby assuring that every point on the rails is subject to a stress always less than the sum of the peak values due to various effects such as the following:
(1) vertical bending in breaking adhesion with the ground,
(2) vertical bending in curvature of the ground,
(3) vertical bending in lifting the conveyor off of the ground,
(4) lateral bending due to dragging the conveyor across the ground,
(5) lateral bending due to shifting curvature,
(6) longitudinal stresses due to warping and torsion of the whole conveyor,
(7) longitudinal stresses due to local torsion of the rail due to high lateral forces at the bulb of the rail, and
(8) connection stresses due to oveturning of the rail due to high lateral forces at the bulb of the rail;
(9) connection stresses due to overturning of the rail due to high lateral forces at the bulb of the rail, the assurance coming from the distribution of the peaks.
Yet another object of this invention is to provide an adjustable rail-engaging roller array sufficient to define safe vertical and lateral curvature of the rails during hoisting and shifting of a flexibly shiftable belt conveyor.
Another object of this invention is to provide a long rail-engaging curvature-defining array providing a long shifting step by defining a long interval of substantially constant maximum curvature or slope.
Another object of this invention is to provide an elongate beam means providing a long shifting step by providing a substantial length of support of the rail free of a substantial length of ground, thus enabling a long support rail-engaging curvature and/or slope.
Another object of this invention is to provide a controlled-curvature rail-engaging array with a laterally straight rail entry to insure against lateral bending stresses other than those resulting from controlled curvature and slope.
Another object of this invention is to provide a conveyor-shifting vehicle having an elongate articulate beam string for variably defining curvature in a rail-engaging array, with steering and beam-adjusting means to support the array in such orientation, attitude, and position as to cause straight rail entry into and exit from said array over varying terrain while variably defining curvature and slope.
Another object of this invention is to provide releasable couple between a conveyor-shifting vehicle and a conveyor shifting rail-engaging array to allow for alternative uses of the vehicle, and housing, maintenance, and spares for the array.
Yet another object of this invention is to provide, in shifting conveyors, a set of three rail-engaging roller arrays for imparting three moments to a rail for reflex curvature, the three comprising a central moment of a first sense and magnitude, and two equal other moments of the second sense and half of the first magnitude, for defining two adjacent intervals of equal and opposite constant circular curvature in rails.
Yet another object of this invention is to provide, in shifting conveyors, a first lifting rail-engaging roller array having lateral freedom, and a second laterally-urging rail engaging array having vertical freedom, for independent definition of vertical curvature and horizontal curvature of the rails.
And another object of this invention is to provide, in shifting conveyors, a beam carrying an adjustable rail-engaging roller array which will adjust to provide maximum safe deflections either for conveyors with maximum safe deflection curves approximating constant curvature or for those with maximum safe curvature approximating constant slope.
Accordingly, furthermore, it is an object of this invention to provide a new and improved conveyor shifting apparatus for moving a shiftable conveyor from a first linear position to a second position, which apparatus includes a pair of shifting beam strings spanning the conveyor and slidably cooperating with both rails in the conveyor to progressively shift the conveyor sections into the second position.
Another object of this invention is to provide a new and improved conveyor shifting apparatus of the steerable non-railbound and shifting design, which includes a pair of shifting beam strings defined by an articulated shifting beam or beams provided with rail engaging assemblies containing roller mechanisms for engaging the rails of a shiftable conveyor and displacing the conveyor sections in the shiftable conveyor from a first linear position to a second linear position displaced a selected distance from the first linear position.
Another object of the invention is to provide a new and improved conveyor shifting apparatus which includes a pair of shifting beam strings formed by multiple shifting beams in end-to-end articulated relationship, and positioned on either side of a set of shiftable conveyor sections and in engagement with the rails of the shiftable conveyor sections by means of at least one roller mechanism in each shifting beam, with respectively opposed ones of the shifting beams in the shifting beam strings maintained in substantially parallel relationship as the shifting beam strings articulate responsive to the movement of a supporting straddle crane or lifting device along the shiftable conveyor, to displace the shiftable conveyor sections a selected distance from a first linear position to a second linear position.
Yet another object of the invention is to provide a conveyor shifting apparatus which is used in cooperation with a straddle crane or alternative lifting and forward-moving device having a supporting gantry frame and tracks or wheels in cooperation with the gantry frame to effect forward movement, the conveyor shifting apparatus including a first group of shifting beams fastened end-to-end in linear, articulated relationship and supported on each side of the shiftable conveyor by lift frames attached to the straddle crane, and multiple roller mechanisms extending downwardly from each of the shifting beams and in engagement with the rails of the shiftable conveyor sections, for traversing the rails and successively urging the shiftable conveyor sections and the shiftable conveyor from a first linear position to a second linear position displaced from the first position, responsive to the forward motion of the straddle crane and the lateral pressure applied to the conveyor sections by means of the shifting beams and the roller mechanisms.
A still further object of this invention is to provide a new and improved conveyor shifting apparatus which is supported and operated by a novel straddle crane and includes a pair of shifting beam strings which contain multiple shifting beams positioned in end-to-end relationship and fitted with articulated joints, the shifting beam strings spaced in substantially parallel relationship on each side of several of the shiftable conveyor sections and attached to the rails of the shiftable conveyor sections by means of roller mechanisms which engage and traverse the rails joining the conveyor sections responsive to forward movement of the supporting straddle crane, to successively urge the rails and the shiftable conveyor sections from a first linear position displaced a selected distance from the first position, in order to move the shiftable conveyor closer to the point of mining.
SUMMARY OF THE INVENTION
These and other objects of the invention are provided in a laterally travelling conveyor system comprising a flexibly shiftable conveyor having a sequence of roller-carrier frames and a pair of rails tied together with connections having a degree of freedom, and further comprising a steerable hoisting and guiding vehicle carrying an elongated beam carrying an adjustable rail-engaging guide array for carrying the conveyor laterally by the rails in safely controlled and guided distributed curvature.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood by reference to the accompanying drawings, wherein:
FIG. 1 is a perspective view of a preferred embodiment of the conveyor shifting apparatus, which illustrates a novel straddle crane supporting a shifting framework of beam strings and roller array in functional position with respect to a novel shiftable conveyor;
FIG. 2 is a diagram of the straddle crane in travelling position over a shiftable conveyor, more particularly illustrating the lateral displacement of the conveyor by travelling curvature responsive to the movement of the straddle crane;
FIG. 3 is a plan view of the apparatus in FIG. 1 with parts omitted for clarity, taken along lines 3--3 in FIG. 1, more particularly illustrating the shifting beam strings in the conveyor shifting apparatus and the displacement of the shiftable conveyor in travelling curvature, responsive to the forward motion of the straddle crane;
FIG. 4 is a side elevation, partially in section taken along lines 4--4 in FIG. 1, more particularly illustrating one side of the conveyor shifting beam string and array in functional engagement with the shiftable conveyor and suspended from the straddle crane;
FIG. 5 is a sectional view taken along lines 5--5 in FIG. 1, more particularly illustrating the functional position of the conveyor shifting apparatus engaging the shiftable conveyor;
FIG. 6 is a sectional side view of a typical mounting of a shiftable conveyor belt-carrying idler attached to an idler stringer in the conveyor sections;
FIG. 7 is a sectional view of the carrying idler and the idler stringer of the shiftable conveyor illustrated in FIG. 6;
FIG. 8 is a sectional view of a typical mounting of the conveyor belt return idler to the stringer supports in the conveyor sections;
FIG. 9 is an end elevation of the conveyor belt return idler mount illustrated in FIG. 8;
FIG. 10 is an end elevation of a preferred configuration for the spindle base plate and spindle housing components of the shifting beams;
FIG. 11 is a perspective view of a preferred spindle base plate and spindle;
FIG. 12 is a plan view of a preferred shifting beam articulation connection used to facilitate articulated movement of the shifting beams in the shifting beam strings;
FIG. 13 is a side elevation of the shifting beam connector illustrated in FIG. 12;
FIG. 14 is a lateral section of the articulated beam of FIG. 12 of the conveyor shifting apparatus, with spindle and roller pairs assembled therewith;
FIG. 15 is a side elevation of the conveyor shifting apparatus illustrated in FIG. 14;
FIG. 16 is a side elevation of a preferred heavy link component of the rail engaging assembly illustrated in the conveyor shifting apparatus in FIGS. 14 and 15;
FIG. 17 is a side elevation of a preferred light link component of the rail engaging assembly illustrated in the conveyor shifting apparatus in FIGS. 14 and 15;
FIG. 18 is an end elevation of the rail engaging assembly in open configuration with respect to one of the rails in the shiftable conveyor;
FIG. 19 is an exploded sectional view of a rail of the shiftable conveyor and the rollers to be brought to engagement with the rail;
FIG. 20 is a front elevation of a preferred roller housing component of the rail engaging assembly;
FIG. 21 is a sectional view, taken along lines 17--17 in FIG. 20, of the roller housing illustrated in FIG. 20.
FIGS. 22 and 23 are orthogonal elevation section details illustrating a preferred articulated rail-to-sleeper connection of the invention;
FIG. 24 is a schematic plan of the optimum travelling curvature of a first embodiment of the invention;
FIG. 25 is a schematic plan of a substantial length of a second preferred embodiment of the conveyor of the invention, illustrating optimum travelling curvature thereof;
FIG. 26 is a more detailed plan of a substantial length of the conveyor of the invention, also illustrating the second major embodiment of the shifter of the invention;
FIG. 27 is an elevation section of the apparatus of FIG. 26, taken on line 129--129 in FIG. 26;
FIG. 28 is a section showing a rotating lifting and shifting means of the invention;
FIG. 29 is a partial elevation, partial section of a torquing means of the invention;
FIG. 30 is an elevation of a telescoping rail joint of the invention;
FIG. 31 is a plan view of the rail joint illustrated in FIG. 30;
FIG. 32 is a central plan section of the rail joint illustrated in FIG. 30, taken on line 168--168 in FIG. 30; and
FIG. 33 is a central cross-section of the joint illustrated in FIG. 30, taken on line 169--169 in FIG. 30.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 of the drawings, the conveyor shifting apparatus of this invention is generally illustrated by reference numeral 1, and is illustrated in functional configuration on a shiftable conveyor 15 of the invention. The straddle crane 2 of the invention serves to provide the linear and lateral motive forces necessary to achieve lateral shifting of the conveyor sections 16 in the shiftable conveyor 15, and operates by means of drive tracks 7, mounted on columns 5 in gantry frames 3, which are spaced by spacer beams 6 and are positioned astride the shiftable conveyor 15 by means of trolley beams 4. Trolleys 8 are relatively movable on the trolley beams 4 by means of trolley cables 12 and the cooperating cable rollers 12a, responsive to the trolley winch drive 13. Operation of the winch drive 13 serves to position the trolley hydraulic rams 9, attached to the trolleys 8, and the sawhorse-shaped lift frames 11, positioned on the piston end of the trolley hydraulic rams 9, in proper vertical orientation on the trolley beams 4. A cab 10 is positioned between the forward ones of the trolley hydraulic rams 9 and the lift frames 11 to provide a control module from which the drive tracks 7 can be steered to facilitate proper re-alignment of the shiftable conveyor 15, as hereinafter described. Steps 14, located in the forward one of lift frames 11, serve to provide access to the cab 10.
The conveyor shifting apparatus 1 includes a rail-engaging array 30 comprising shifting beam strings 31, which in this preferred embodiment are generally square or rectangular in cross section, and are articulated in end-to-end relationship. The shifting beam strings 31 are suspended from the lift frames 11 by removable or permanent attachment between the bottom ends of the lift frames 11 and two of the shifting beams 38 in each of the shifting beam strings 31, respectively, as illustrated. In this preferred embodiment of the invention five such shifting beams 38 are utilized in each of the shifting beam strings 31, and the second one of shifting beams 38 in each of the shifting beam strings 31 from each end are connected to the lift frames 11. As further illustrated in FIG. 1, the shifting beam strings 31 are disposed in approximately parallel, spaced relationship on each side of the shiftable conveyor 15, and the shifting beams 38 are joined to each other in pivotal adjustable articulating relationship by means of a pair of powered shifting hinges 43. Multiple rail-engaging suspender assemblies 92 are suspended in spaced array from the shifting beams 38, and engage the rails 39 of the shiftable conveyor 15, to facilitate traversal of the rails 39 and progressive lifting and guiding of the respective conveyor sections 16 in travelling curvature responsive to the forward progress of the straddle crane 2 along the shiftable conveyor 15, defining a curvature as hereinafter described.
Referring now to FIGS. 1-4, and to FIG. 2 in particular, a flexibly shiftable conveyor 15 is illustrated, with head station 41 at one end, a tail station 42 at the opposite end, and the apparatus 1 comprising a straddle crane 2 astride the shiftable conveyor 15. As further illustrated in FIG. 3, the rail engaging array 30 is in functional position carried by the straddle crane 2, and as the straddle crane 2 moves in the direction indicated by the arrow along the shiftable conveyor 15, the conveyor sections 16 located between the straddle crane 2 and the tail section 42 are successively being pulled into alignment with that previously adjusted portion of the shiftable conveyor 15 which is located between the straddle crane 2 and the head station 41. The mechanics of this adjustment of the shifting conveyor 15 from a first linear position illustrated by that portion of the shiftable conveyor 15 which is located between the straddle crane 2 and the tail station 42, to a position in linear alignment illustrated by the segment located between straddle crane 2 and head station 41, will be hereinafter described more in detail. As further illustrated in FIG. 3, the shifting beam strings 31 permit the articulated shifting beams 38 to assume the configuration of those conveyor sections 16 in shiftable conveyor 15 which are positioned between the shifting beam strings 31 and are in the process of being shifted from the first linear configuration to the second linear position. Referring now to FIG. 4, the rail-engaging array 30 is shown in elevation view, the straddle crane 2 illustrated in elevation section, and the varying clearance of the module sleepers 36a, 36b, and 36c above the ground, upon which the shiftable conveyor 15 rests when operating, is illustrated, which clearance facilitiates the shifting operation illustrated in FIGS. 1-3. It will be appreciated that the general height adjustment above the ground level 115 of the conveyor sections 16 which are engaged by the rail engaging suspender assemblies 92 is achieved by adjustment of the trolley hydraulic rams 9, which carry lift frames 11, and that the varying clearance of the individual assemblies is otherwise adjusted, as will be explained. Note is taken that the rail 39 is in this view of FIG. 4, curved at sleepers 36a, straight at sleepers 36b, and curved again at sleepers 36c.
As further illustrated in FIGS. 1 and 5-9, the shiftable conveyor 15 includes module sleepers 36, 36a, 36b, and 36c, (generally called 36) situated in spaced relationship in each of the conveyor sections 16 along the entire length of the shiftable conveyor 15. Stringer supports 17 are secured to the module sleepers 36 by means of support mount plates 18, with appropriate fasteners. Stringer support braces 34 and module braces 35 serve to maintain the stringer supports 17 in substantially vertical alignment on module sleepers 36, and idler stringers 21 are mounted in angular relationship on the stringer supports 17, and connect the stringer supports 17 to each other in each one of the conveyor sections 16. Referring specifically to FIGS. 5-7, conveyor carrying idlers 19 are provided in spaced, rotatable relationship in each of the conveyor sections 16, and are each attached to the respective idler stringers 21 by means of an end connection 22, secured to an idler shaft 28, on each of the conveyor carrying idlers 19 by means of an end connection bolt 29, as illustrated in FIGS. 6 and 7. The end connections 22 are also connected to a pivot plate 23, which is in turn secured to the idler stringer 21 by means of a pivot pin 25. A pivot plate slot 24, and a pivot stop 26, serve to facilitate adjustment of the conveyor carrying idlers 19 with respect to the stringer support 17. As illustrated in FIGS. 5, 8 and 9, multiple belt return idlers 20 are provided beneath the conveyor carrying idlers 19 in shiftable conveyor 15, and are each provided with an idler shaft 28 and end connections 22, for attachment to the stringer supports 17 by means of a chain 29a, and a cooperating link slot 33, with a clamp 33a and a lift rod 33b. It will be appreciated by those skilled in the art that the attachment of the conveyor carrying idlers 19 and the belt return idlers 20 can be made in a variety of ways, it being necessary only to provide a means for flexible support of the conveyor belt 40 in each of the conveyor sections 16 of the shiftable conveyor 15. Since the entire length of the shiftable conveyor 15 between the head station 41 and the tail station 42 is shaped by discrete, individual conveyor sections 16, which are connected only by the rails 39 and the conveyor belt 40, substantial flexibility is built into the conveyor line to facilitate successive shifting of the conveyor sections 16.
Referring now to FIGS. 2 and 13 of the drawings showing a further preferred embodiment of another aspect of the invention, each shifting hinge 43 in the shifting beam strings 31 includes an outside connector plate 49 and a cooperating inside connector plate 52 at the top, and a second outside connector plate 49 and companion inside connector plate 52 at the bottom, for each shifting hinge 43 which connects the shifting beams 38. Accordingly, two pairs of the outside connector plates 49 and inside connector plates 52, respectively, are provided as components of each shifting hinge 43. As illustrated in FIG. 13, the plate legs 56 of one pair of the outside connector plates 49 and inside connector plates 52 are attached to a common end of one of the shifting beams 38, while the plate legs 56 of the opposite and cooperating pair of the outside connector plates 49 and inside connector plates 52 are secured to the adjacent one of the shifting beams 38. A shifting beam plate 51 is welded or otherwise attached to each of the adjacent shifting beams 38, and is pivotally secured between each pair of the outside connector plates 49 and the inside connector plates 52, respectively, by means of a connector pin 54. This mechanical arrangement permits each of the adjacent shifting beams 38 in the shifting beam strings 31 to articulate on the connector pins 54, as hereinafter described. In a most preferred embodiment of this aspect of the invention a shifting beam ram 57 joins the top ones of outside connector plates 49 and inside connector plates 52 in each plate combination, and includes a cylinder 58 and a cooperating clevis 59, which is secured by a connecting pin 63 to the outside connector plate ear 50, of the inside connector plate 49. A cooperating ram rod 60 is secured to the inside connector plate ear 53 of the inside connector plate 52 at one end, by means of another connecting pin 63. The ram rod 60 extends into the cylinder 58 and is attached to the piston 61. Accordingly, the relative pivot of each shifting beam 38 with respect to the adjacent shifting beam 38 in the shifting beam strings 31 is limited and controlled by the stroke of the shifting beam rams 57.
Referring further to FIGS. 10-12, in further disclosure of a preferred embodiment of another aspect of the invention, generally cylindrically-shaped, hollow spindle housings 44 are mounted in spaced relationship in the shifting beams 38, with the top end of each of the spindle housings 44 extending from attachment to the shifting beams 38. Referring specifically to FIG. 11, a spindle base plate 46 is provided with a base plate top 46a, and a pair of base plate flanges 46b extending downwardly from the base plate top 46a. A cylindrical spindle 45 extends from attachment to the base plate top 46a, and is provided with a spindle bore 48. A spindle 45 is designed to register with and project adjustably upward through each of the hollow spindle housings 44, as illustrated in FIG. 10. Base plate flanges 46b of each spindle base plate 46, are also provided with base pin holes 47, as illustrated.
Referring now to FIGS. 14-17 of the drawings each of the rail-engaging suspender assemblies 92 of the conveyor rail engaging array 30 is mounted to a spindle base plate 46 by means of a pair of light links 73 and two heavy links 77, which are more particularly illustrated in FIGS. 16 and 17. Each light link 73 is shaped by light link flanges 74 spanning a light link body 75, while each heavy link 77 is characterized by somewhat thicker heavy link flanges 78 and a thinner heavy link body 79. As illustrated in FIGS. 14 and 15, one end of the light links 73 and the heavy links 77 are pivotally attached to the base plate flanges 46b of the spindle base plate 46 by means of link pins 81, which register with pin holes 73a in the light links 73 and the heavy links 77, and with the base pin holes 47 in the base plate flanges 46b. Snap rings 55 serve to register with grooves provided in the link pins 81 in order to pivotally secure the light links 73 and the heavy links 77 to the base plate flanges 46b. The opposite ends of the light links 73 are attached to the light link brackets 85, which extend from an outside roller housing 84 and an opposing inside roller housing 94, respectively, as illustrated. Furthermore, the opposite ends of the heavy links 77 are attached to heavy link brackets 86, also attached to the light link brackets 85 of the outside roller housing 84 and inside roller housing 94, respectively. A spreader ram 97 is disposed between the outside roller assembly 83, which contains the outside roller housing 84, and the inside roller assembly 93, which includes the inside roller housing 94, as illustrated in FIG. 14. In a preferred embodiment of this aspect of the invention the spreader ram cylinder 98 is attached through a mounting eye 62 to the light link bracket 85 of the inside roller housing 94, by means of a link pin 81, which extends through registering pin holes 73a in the light link bracket 85 and the mounting eye 62. Snap rings 55 serve to maintain the link pin 81 in position and to allow pivotal movement of the light link 73 and the mounting eye 62 of the spreader ram cylinder 98 with respect to the light link bracket 85. The spreader ram piston 99 is provided with a second mounting eye 62, which is connected to the opposite light link bracket 85 positioned on the outside roller housing 84 by means of a second link pin 81, which link pin 81 also attaches the second connecting light link 73 to the light link bracket 85. In a most preferred embodiment, and referring again to FIG. 15, a link pin bushing 82 is provided on each of the link pins 81 which secure the mounting eyes 62 located on the spreader ram cylinder 98 and the spreader ram piston 99, to the light link brackets 85, respectively, in order to facilitate positive operation of the spreader ram 97, as hereinafter described.
As heretofore noted, one end of one of the heavy links 77 is attached to a heavy link bracket 86, fastened to the inside roller housing 94, while the end of the second heavy link 77 is secured a second heavy link bracket 86, attached to the outside roller housing 84. Accordingly, referring now to FIG. 18, when the spreader ram 97 is activated by appropriate controls (not illustrated) to extend the spreader ram piston 99 from the spreader ram cylinder 98, the outside roller housing 84 is moved away from the inside roller housing 94, in order to facilitate removal of each of the rail engaging suspender assemblies 92 from the rails 39. Conversely, retraction of the spreader ram piston 99 into the spreader ram cylinder 98 causes the outside roller housing 84 and the inside roller housing 94 to converge, and the outside roller 87 and inside roller 95 to engage the outside rail shoulder 104 and inside rail shoulder 105, respectively, as illustrated in FIGS. 14 and 18.
Referring now to FIGS. 14, 15, and 18-21, in a most preferred embodiment of another aspect of the invention both the outside roller 87 and the inside roller 95 in the outside roller housing 84 and inside roller housing 94, respectively, are provided with a roller groove 88, which matches the outside rail shoulder 104 and the inside rail shoulder 105 of the rail 39, in order to facilitate smooth roller traversal of the rail head 103 as the straddle crane traverses the shiftable conveyor 15.
Referring again to FIGS. 15, 18, 19, 20, and 21, in yet another most preferred embodiment of a further aspect of the invention the light link brackets 85 in the outside roller housing 84 and inside roller housing 94 are each characterized by a link pin aperture 76 and a spacer bolt aperture 80, spaced from the link pin aperture 76. Furthermore, the heavy link bracket housing 86 is welded or otherwise fixedly secured to the light link bracket 85 and is provided with a heavy link bracket aperture 117. Each light link bracket 85 is shaped to define a shaft mount plate 106, which is provided with an interior space to accommodate a wheel axle 89, journalled for rotation in the roller shaft aperture 111 and roller shaft seat 96. As illustrated in FIG. 19, a wheel axle 89 secures the outside roller 87 in the shaft mount plate 106, and in a most preferred embodiment, both the outside roller 87 and the inside roller 95 are provided with tapered bearing seats 112, and cooperating bearing races 113 to accommodate bearings 114, in order to facilitate a smooth rotation of the outside roller 86 and inside roller 95 on the respective wheel axles 89. A spacer bolt 90 in inserted in the spacer bolt apertures 80, provided in the light link brackets 85, and is secured by the spacer bolt nut 91, as illustrated in FIG. 15, in order to secure the wheel axles 89 in the roller shaft aperture 111 and roller shaft seat 96, of the outside roller housing 84 and the inside roller housing 94, respectively.
Referring again to FIGS. 14 and 15 of the drawings in a further preferred embodiment of the invention each spindle 45, attached to a spindle base plate 46 by means of welds 63a, is inserted concentrically inside a spindle housing 44, which is welded to the shifting beams 38. Furthermore, an adjustable double-acting suspender ram 65, having a suspender cylinder 68, is attached by means of a ram base 72, to the base plate top 46a of each spindle base plate 46, and extends into each spindle 45. Each suspender cylinder 68 is further provided with a suspender bore 70, with one end of a suspender rod 66 extending through the top of the spindle housing 44, and a suspender rod stop 67 at the opposite end of the suspender rod 66. A gland 69 is provided at the top of the suspender cylinder 68, and the projecting and threaded end of the suspender rod 66 is secured to the top of the spindle housing 44 by means of suspender mount nuts 71. Accordingly, each rail engaging suspender assembly 92 in the shifting beams 38 is carried adjustably by a spindle base plate 46, which is suspended from a spindle housing 44 and the shifting beams 38, and each spindle 45 is permitted and caused to move up and down inside the cooperating spindle housing 44 by the action of a suspender ram 65, in order to adjustably define the curvature of the rails 39 and the clearance of the module sleepers 36 as mentioned hereinbefore, as the rail engaging suspender assemblies 92 traverse the rails 39. In a still further preferred embodiment of this aspect of the invention, a spindle bushing 64 is provided between the inside surface of the spindle housing 44 and the outside surface of the spindle 45, in order to produce a closer tolerance and minimize lateral movement while allowing pivoting of the suspended rail engaging suspender assemblies 92 and the spindle base plate 46 with respect to the shifting beams 38.
Referring now to FIGS. 22 and 23, an alternative design of the rail 39 is shown in isolated section in FIG. 23 having a threaded pin 108 welded thereto, with a cooperating lock nut 108b, having locking means known in the art. FIG. 22 shows a section of a hollow module sleeper 119 with a slotted hole 108a, receiving the threaded pin 108 locked by a nut 108b with some degree of freedom, to wit, in pivoting about the pin 108 and also lengthwise of the rail 39 in the oversize design of the slotted hole 108a.
FIG. 24 schematically shows the deflected shape 110 of the shiftable conveyor 15 components which are supported below the rail-engaging array 30. Only 4 sets of the outside rollers 87 and inside rollers 95 are shown, being those which might have a substantial lateral action in bringing about such a shape, as hereinafter explained. The other outside rollers 87 and inside rollers 95, respectively, are deployed primarily to give vertical support to the shiftable conveyor 15, and define the desired vertical curvature. The shape is the shape of a Vierendeel Frame with relative end translation movements enforced.
Now that the first preferred major embodiment of the invention has been described, another sometimes preferred embodiment will be shown, illustrating a differing novel shiftable conveyor and suitable novel shifting array.
Referring now to FIG. 25, which is a schematic plan, a second major shape of a conveyor frame 107 of the invention is illustrated, and includes conveyor support sections 118, sleepers 119 and rails 120, which are similar to the conveyor sections 16, module sleepers 36, and rails 39, respectively, of the previous embodiment as illustrated in FIG. 1, respectively, with joints 121 and novel telescoping joints 122 and 123 having a releasable telescoping degree of freedom. The telescoping of joints 122 and 123 allows the conveyor as a whole to take on the smoother s-shape illustrated by the whole of the FIG. 25, since the conveyor support sections 118 are not so constrained, compared to the conveyor section 16 of the previous embodiments, to move mainly in translation, but can also rotate to a degree, allowing a much larger and safer shifting step.
FIGS. 26 and 27 represent larger and more detailed plans of the conveyor frame 107, supporting a conveyor belt 124, comprising a segment of the length of the conveyor 125, which also has a head station 41 and a tail station 42, as illustrated in FIG. 2. Moreover, the shifter 126, comprising a novel steerable straddle frame 127 with a novel shifting array 128 is shown. This is all further shown in elevation section 27.
Further referring to FIGS. 26 and 27, the straddle crane 127 supports powered trolleys 130 running on beams 131 supported on columns 132, with kingpins 133 steerably housed therein, the king pins 133 mounted on tracks 134, all by means well known in the art, including tie-beams 135. The powered trolleys 130 support double-acting hoist rams 136 from swivels 137, by means well known in the art.
Hoist rams 136 have rods 138 with swivel supports 139 adjustably supporting the shifting array 128 in service position, all by means well known in the art.
The shifting array 128 comprises a pair of large beams 140, torquing roller arrays 141, and lifting suspender drum apparatus 142, with both the torquing roller arrays 141 and the lifting suspender apparatus 142 engaging the rail 120.
As illustrated in FIGS. 26 and 28 each of the eight lifting suspender drum apparatus 142 comprises a drum 143 rotatably mounted in the large beam 140 and pivoted and powered by a ring gear and motor assembly 144, and bearing means 144a, elements which are well known in the art. The drum 143 has a spindle housing sleeve 145 mounted eccentrically in the drum 143, to selectively carry the spindle housing sleeve 145 to the center or off center of the large beam 140 by operation of the ring gear and motor assembly 144. FIG. 26 illustrates the spindle housing sleeve means 145 off-center to accommodate and define the s-shaped curve in the rails 120. Suspender 146 is an elongated version of the rail engaging suspender assembly 92 illustrated in FIGS. 14, 15 and 18. The greater length of the suspender 146 is facilitated because of the lack of lateral sway of the suspender 146 as compared to that of the rail engaging suspender assembly 92.
Referring again to FIGS. 26 and 27 and additionally to FIG. 29, each torquing roller array 141 comprises a cylindrically-shaped rotating housing 147 powered in rotation about a vertical axis by a torque, motor, and bearing 148 mounted in the large beam 140. Each rotating housing 147 houses a pair of roller pins 149 mounted in cylindrical bearings 150, the roller pins 149 having limited clearance to ride up and down in the cylindrical bearings 150. The rollers 151 are mounted to the roller pins 149 by means of bearings 152 and are vertically positioned to clear the rail 120 by hydraulic rams 153 attached thereover; in the alternative, the roller pins 149 may be left free-running by leaving the rotating housing 147 ported. In FIG. 26 the torque motor and bearings 148 are shown to be acting to torque the rotating housings 147 in the counter-clockwise direction and the center rotating housings 147 in the clockwise direction, thereby imparting the traveling s-shaped curve to the rails 120 through the rolling contact of rollers 151 on the rail heads 103 of the rails 120. The torque of each central torquing roller array 141 is twice that of each end torquing roller array 141, thereby imparting equal curvature to four intervals of the rails 120 defined by the six torquing roller arrays 141. At the same time, lifting suspender drum apparatus 142 hoists the rails 120 into a smooth even curve. Referring now to FIGS. 30 through 33, which illustrate a preferred embodiment of a telescoping joint 123 having an automatically releasible degree of freedom, rail segments 120a and 120b of rails 120 have feathered ends 154 mating with space therebetween for a corrugated frame 155. Feathered ends 154 comprise slanted web slice plates 156 welded between feathered rail bulbs 120a and 120b and feathered flanges 157 and extending into cut-outs 158 in webs 159. Web splice plates 156 have slotted holes 160, carrying headed keepers 161 insuring against excessive separation of the feathered ends 154. The feathered ends 154 have considerable bending strength imparted by the channel sleeve 162 comprising a rail segment 163 and slotted fittings 164 welded thereto. Slotted fittings 164 are provided with snap lugs 165 in slots 166, adapted to snap into snap-recesses 167 in the feathered flanges 157.
The foregoing two major embodiments and the operation thereof will now be further described.
In operation, and referring again to FIGS. 1-22 of the drawings, when it is desired to utilize the conveyor shifting apparatus 1 of this invention, the rail engaging array 30 is initially suspended from the straddle crane 2 which is placed astraddle the shiftable conveyor 15, optionally by lifting the whole over, or driving over the tail station 42 or otherwise. The lift frames 11 which are attached to selected ones of the shifting beams 38 in the shifting beams 31 are attached to the trolley hydraulic rams 9, as illustrated in FIG. 1, and each of the spreader rams 97 are initially activated by operation of appropriate controls known to those skilled in the art, to extend the respective spreader ram pistons 99 and open the outside roller housing 84 and inside roller housing 94, as illustrated in FIG. 18. This open configuration of the rail engaging suspender assemblies 92 is achieved as the opening operation of the spreader ram 96 exerts lateral pressure on the link pins 81 joining the mounting eyes 62 of the spreader ram piston 99 and the spreader ram cylinder 98, to spread the outside roller assembly 83 and the inside roller assembly 93. Each of the shifting beam strings 31 are then raised by operation of the trolley hydraulic rams 9 to a position over the respective rails 39, and the shifting beam strings 31 are are then slowly lowered and adjusted by the trolley hydraulic rams 9 until the respective ones of the outside roller housings 84 and inside roller housings 94 are adjacent to the rail head 103 of each rail 39. When each rail engaging suspender assembly 92 is fairly near the proper position the suspender rams 65 and shifting beam rams 57 are actuated to bring the apparatus in proper relationship to the rails 39 as illustrated in FIG. 18, and the spreader rams 97 are again activated by appropriate controls to close the outside roller housings 84 and inside roller housings 94 and secure the outside rollers 87 and the inside rollers 95 against the outside rail shoulder 104 and inside rail shoulder 105, respectively, of the rails 39, as illustrated in FIG. 14.
When each of the rail engaging suspender assemblies 92 are in functional position as illustrated in FIG. 14, the trolley hydraulic rams 9 and suspender rams 65 are again activated in the required way to lift the shifting beams 38 and the attached rail engaging suspender assemblies 92 and raise the conveyor sections 16 adjacent the shifting beam strings 31 and the module sleepers 36 beneath the shifting beams 38, off the ground to a desired varying degree shown and mentioned in association with FIG. 2, to define the vertical curvature of the rails 39. This occurs as an upward force is applied by the trolley hydraulic rams 9 to the shifting beams 38 attached to the lift frames 11, and the shifting beams 38 move upwardly, along the suspender rods 66 in the suspender rams 65. Each suspender ram 65 provides local adjustment to the outside roller assembly 83.
The above described initial lifting sequence is executed with the conveyor initially in operation disposition where the rails 39 are substantially straight. Also, the conveyor shifting apparatus 1 will be initially located immediately adjacent to the head station, 41 (or, if desired, the tail station 42). Therefore, the first adjusted supported position of the rails 39 will be curved vertically, but straight in plan. Then, by employment of means well known in the art, the head station 41 will be lifted and shifted slowly through the desired shifting step. Simultaneously, the rail engaging array 30 is brought into congruent offset curvature by simultaneous operation of the trolley winch drives 13 and the shifting beam rams 57, resulting in lateral s-shaped curvature, as well as the vertical curvature. The shifting step and the s-curvature are planned so as to define the curvature of the rails 39 within safe limits. The maximum vertical curvature is designed to be some distance from the maximum horizontal curvature, thereby providing a diminished total.
The straddle crane 2 is then moved forward away from the head station 41 in the direction of the arrow as illustrated in FIGS. 2 and 3, and the lifting and lateral pressure exerted by the rail engaging suspender assemblies 92 on the rails 39 causes those conveyor sections 16 which are spanned by the shifting beam strings 31, to move laterally from a first linear position to a second linear position which is displaced from the first position. As the straddle crane 2 continues its forward progress, the shifting action continues as the outside rollers 87 and the inside rollers 95, mounted in the outside roller housing 84 and the inside roller housing 94, respectively, of the rail engaging suspender assemblies 92, traverse the rail heads 103. Accordingly, the conveyor shifting apparatus 1 can be used to shift the entire length of the shiftable conveyor 15 from the first position to a displaced second configuration, as illustrated in FIG. 2, with the final step of shifting the tail station 42 accomplished, just as the head station 41 was shifted, with a simultaneous operation of the rail engaging array 30 to maintain congruence.
A great advantage of the rail engaging array 30 with its great range of articulation is that the apparatus can approximate and accommodate a wide variety of a s-shaped curves, including the rippled curve of the chords of the Vierendeel frame. The local irregularities of the deflected Vierendeel frame are accomodated by the partial latent freedom of the rail engaging suspender assemblies 92.
Referring again to FIG. 2, it will be appreciated by those skilled in the art that a conventional tractor 116, or equivalent machinery must be used to move the head station 41 and similarly the tail station 42, of the shiftable conveyor 15, according to the knowledge of those skilled in the art. However, it will be further appreciated that the conveyor shifting apparatus 1 of this invention can be used to relocate, and more particularly, to laterally relocate a shiftable conveyor such as the shiftable conveyor 15 of substantially any length or any type, to any desired new position which is eigher parallel to or at a selected angle with respect to the original conveyor line. This option can be realized by guiding the straddle crane 2 or an equivalent conveyor shifting apparatus suspension system to whatever degree is necessary in order to achieve a specified and desired second conveyor location.
Now considering the second major embodiment of FIGS. 22-33 the operation of the shifter 126 proceeds similarly to that of the conveyor shifting apparatus 1. The conveyor 125 is initially straight and empty. The straddle crane 127 carries the large beams 140 as far outboard and apart as possible, and if possible, drives over the tail station 42 of the conveyor 125. Otherwise, the straddle crane 127 is hoisted, by crane located at the mine, over the conveyor 125. The lifting suspender drum apparatus 142 is revolved to bring the suspenders 146 to the central axis of the large beams 140. The rotating housings 147 are then rotated so as to maximize the clearance between the pairs of rollers 151. The powered trolleys 130 and hoist rams 136 are powered to carry large beams 140 into alignment with and well over the rails 120. Hoist rams 136 then operate to lower the large beams 140 sufficiently for engagement of the suspenders 146. Suspenders 146 are engaged after the fashion of the rail engaging suspender assemblies 92, already described, thereby gripping the rails 120. The hoist rams 136 then lift the large beams 140 sufficiently to lift the conveyor 125 by the suspenders 146 barely clear of the ground. Means of the art are then activated to begin shifting of the tail station 42. Hydraulic rams 153 operate to position the rollers 151 at the level of the rail bulbs 120a and 120b of the rail 120. The torque motor and bearing 148 torques the rotating housings 147 to bring the rollers 151 into engagement with the rails 120, which forces the rails 120 into flexure. Axial forces are induced in the rails 120 which causes the snap lugs 165 to snap out of the snap recesses 167, thereby compressing the corrugated springs 155, and allowing release and diminution of the axial forces, and facilitating the s-shaped curvature illustrated in FIG. 25.
When the tail station 42 and s-shaped curve approximate the desire safe shifting step, the straddle crane 127, which is powered by means well-known in the art, drives the shifting array 128 along the conveyor 125. Conveyor support sections 118 successively pass through the straddle crane 127, and be shifted. Telescopic joints 122 and 123 enter the torquing roller arrays 141 in sequence, and the major circumference of the rollers 151 bear on the web splice plates 156, thereby compressing each corrugated spring 155 and releasing the telescoping joints 122 or 123 to allow curvature simultaneously with the need for such curvature, all of which occurs within the span of the pairs of rollers 151 of the torquing roller array 141. The exit procedure and shifting of the head station 41 is similar to and deducible from the reverse of the aforementioned steps. A reversal of the above procedure from the head station 41 to the tail station 42 might be undertaken to take another shifting step, optionally.
The releasibility of the telescoping joints 122 and 123 is preferred, but not imperative. This function offers the advantage of additional stiffness when shifting is not transpiring, and sufficient flexibility when it is. Other embodiments of releasable telescoping might serve, such as a non-automatic release, in non-exclusive particular. Likewise, other configurations of roller arrays would serve; for example, positioning the hydraulic rams 153, while convenient, might be omitted, provided roller pins 149 are secured by means in the housings. Other lifting roller arrays serving the ends of the suspenders 147 might serve to impart vertical lift and curvature, according to methods well-known in the art. Likewise, one or two large beams such as the large beams 140 might be carried by one or more side-boom tractors and achieve an acceptable shifting result without the use of a straddle crane 127. It is also possible for three unconnected side-boom tractors to carry three distinct torquing roller arrays such as the torquing roller arrays 141, but mounted on special sidebooms instead of the large beams 140, to accomplish the distributed curvature disclosed. Even so, these variations are all envisioned within the scope of the invention.
The operation and advantage of the equal constant curvature combined with the smooth vertical rail deflection is now evidently obtained, especially since the sum of stresses in the rails 120 is controlled to a tolerable limit. The advantage of the degrees of freedom in the rails 120 is now evident in the greater safe shifting step.
While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made in the invention and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention. | A shifting conveyor apparatus with a belt conveyor laterally shiftable, by flexibly mounted flexible rails therealong, towards a progressive excavation, including a travelling varingly-curving rail-engaging guide array for carrying and drawing the conveyor laterally by the rails, keeping the rails and the conveyor belt in safely controlled and guided distributed travelling curvature. | 1 |
RELATED APPLICATIONS
[0001] This application claims priority of U.S. Provisional Application Serial Nos. 06/290,652 filed May 15, 2001 and 60/336,573 filed Dec. 4, 2001.
[0002] This application is also related to co-pending U.S. patent application Ser. No. 09/603,234 entitled “Method and Apparatus for Production of Labels.”
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to a method and apparatus for the production of folded radio frequency (RF) labels for application to clothing, linens, towels, and other goods, and more particularly to a label incorporating radio frequency (RF) devices produced by the apparatus and method of the invention.
[0005] 2. Description of the Related Art
[0006] The attachment of labels to cloth goods such as clothing, linens and towels is a common practice used to set forth information such as trademarks and trade names, material identification and characteristics, sizes, care instructions, and so forth. In addition, legal requirements necessitate the use of labels in clothing or on linens. A method and apparatus for producing individual folded labels from a ribbon of labels is presented in published PCT application WO 00/50239 and is incorporated in its entirety herein.
[0007] Folded labels are commonly used in the industry and come in a number of different forms including endfolds, centerfolds, J folds, Booklet fold, Manhattan-folds, and mitrefold labels. While each of these different forms has a particular use, the centerfold and endfold labels are the most popular.
[0008] In addition to providing this important information, the label is part of the object. Unfortunately, it is not unusual for a label, especially a skin contact clothing label, to irritate the customer. This can result in the customer forming a negative attitude regarding the quality of the entire garment. Quite often the customer will cut the offending label out of the garment. This not only prevents the customer from having the proper care instructions, it also removes the product identification from the garment, further reducing repeat sales.
[0009] Currently most folded labels are produced using what is referred to in the industry as the “cut and fold” technique, that is the labels are indexed, cut from a ribbon of material and then folded. Using this technique about 40-220 labels can be produced a minute with between 5-20% of the labels being considered waste or defective. The most common defect being a distorted fold resulting in the ends of the label not aligning properly. Other defects include turned corners, fanning, and protruding fold-unders.
[0010] Defective labels can significantly increase the cost of the goods. For example, while it costs only about fifteen to twenty-five cents to sew a label into a
[0011] garment in the United States, it can cost five to ten times this amount to replace a defective label. Many labels, especially centerfold, have a tendency to skew while being sewed, thereby increasing the chance for a poor impression. Moreover, RF devices range in cost from three cents to over one dollar. Thus, a defective label can add tremendous cost. If the defective label is not detected and replaced, the goods may have to be classified as seconds and sold at a steep discount. Significantly, if the identification of the defective label is missed it is likely to be recognizable by the customer and adversely affect the overall impression of the goods. The present invention prevents such defects.
[0012] It would be desirable to be able to produce folded labels incorporated with RF devices for storing and transmitting identifying information and that are more comfortable to the apparel customer than current labels. In addition, it is desirable to produce such labels at a higher speed and at a greater efficiency of production for both label and end product manufacturers, and with fewer defects than current methods.
SUMMARY OF THE INVENTION
[0013] The present invention has been developed with the view towards substantially changing the way that labels are used and developed. In particular, an object of the present invention is to provide steps for producing a ribbon of labels with RF devices encapsulated therein, and subdividing the ribbon into individual RF labels using ultrasonic means resulting in individual folded RF labels that are both soft to the touch, i.e., having edges that are generally scratchless to the apparel consumer, and capable of storing and transmitting identifying information and at the same time virtually free of defects.
[0014] Another object of the present invention is to provide steps for incorporating the RF devices into the labels whereby inventory control, pricing control and the tracking of the origin of the merchandise, for example, can be done via the RF devices in the labels.
[0015] The present invention also provides a method and apparatus for attaching a RF device to a carrier strip so that it may be processed into labels.
[0016] The feel of the labels produced in accordance with the present invention assures that the RF labels will remain on the garment when the customer is ready to reorder. Additionally, the use of ultrasonic means to subdivide the RF labels results in a label having the front and back folds sealed together thus preventing the label from being skewed when sewed into a garment. This makes the sewing step more efficient and results in a reduced number of finished goods being classified as seconds, thus providing added cost savings to the garment manufacturer. Furthermore, the present invention allows for the production of RF labels at a rate of 200 to over 1000 per minute, at efficiencies of better than 90%, and at a waste of less than 4%. This is significantly higher than the 40-220 labels per minute produced using the current “cut and fold” technique.
[0017] In one embodiment, the folded pressed ribbon is indexed and then ultrasonically subdivided into individual RF labels.
[0018] In an alternative embodiment, the folded and pressed ribbon is rerolled and shipped to an end user for use in an auto-sewing device.
[0019] The present invention further includes an apparatus for carrying out this method as well as RF labels produced in accordance with the method.
[0020] Still another object of the present invention is to provide for insertion of a device such as an antenna, computer chip, radio frequency inventory/antitheft control devices, acoustical, magnetic or other security or inventory control devices within the folded labels. Such devices may be part of a web or laminate. After the insertion of such inventory/anti-theft devices, edges of the label are sealed and bonded together using known techniques, preferably ultrasonics. As will be discussed in more detail below, such an inventory/anti-theft control device, e.g. a RF device, can be inserted before or after the folding step.
[0021] Another object of the present invention is to provide an apparatus and method for inserting a radio frequency device into a ribbon of labels and registering the cut of the ribbon of labels by sensing the edge or part of the radio frequency device located therein. In this manner, when subdividing the label of ribbons, the actual RF device is detected and not the logo or text message on the label, which decreases the chance of ruining the more expensive RF devices.
[0022] In accomplishing these and other objects of the present invention, there is provided a method for producing individual folded labels incorporating a radio frequency device, the method comprising the steps of providing a ribbon of labels containing a woven logo or text. A carrier strip with a plurality of radio frequency devices spaced thereon is provided and the plurality of radio frequency devices are joined to the ribbon of labels. The ribbon of labels is then folded so as to form at least one folded portion. The folded ribbon is subjected to sufficient heat and pressure to set the at least one folded portion. The ribbon of labels is subdivided into individual folded labels.
[0023] In accomplishing these and other objects of the present invention, there is also provided a label-making apparatus comprising a dispenser for a carrier strip having a plurality of radio frequency devices disposed thereon at spaced intervals. A mechanism linearly advances a ribbon of labels, the ribbon of labels containing a woven logo or text. Means join the plurality of radio frequency devices with the ribbon of labels. A cutting station subdivides an individual label from the ribbon of labels and plurality of radio frequency devices. A sensor in communication with the linear advance mechanism controls the advance of a length of the ribbon of labels to provide proper spacing between the radio frequency devices, cut-edges and a logo on the label.
[0024] The apparatus of the present invention can further comprise an insertion assembly to insert an inventory/anti-theft control device, such as those discussed above, into the RF labels. The insertion assembly can be positioned before or after the folding station or after indexing. In all embodiments, the apparatus can be configured for left or right-hand operation to allow a user to operate more than one unit.
[0025] These and other objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiment relative to the accompanied drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] [0026]FIG. 1 is a perspective view of an apparatus for attaching an RF device to a carrier strip.
[0027] [0027]FIG. 2 is a bottom view of the bar horn of the ultrasonic welder of the apparatus of FIG. 1.
[0028] [0028]FIG. 3 is a front side view of the carrier strip and attached RF devices assembled by the apparatus of FIG. 1.
[0029] [0029]FIG. 4 is a back side view of the carrier strip and RF devices of FIG. 3.
[0030] [0030]FIG. 5 is a perspective view of an apparatus according to one embodiment of the present invention for producing a folded label having a RF device incorporated therein.
[0031] [0031]FIG. 6 is a perspective view of an apparatus according to another embodiment of the present invention for producing a RF label.
[0032] [0032]FIG. 7 is a perspective view of an apparatus for producing a folded label incorporating an RF device according to another embodiment of the invention.
[0033] [0033]FIG. 8 illustrates a label having a RF device incorporated therein in accordance with the apparatus of FIG. 7, with an edge of the label pulled away.
[0034] [0034]FIG. 9 illustrates a RF label with ultrasonically bonded edges in accordance with the apparatus and methods of the present invention.
[0035] [0035]FIG. 10 is a cross-sectional view of the label of FIG. 9 taken along line I-I.
[0036] [0036]FIG. 11 is a perspective view of an end folded label produced by the apparatus and method of the present invention.
[0037] [0037]FIG. 12 is a cross-section of the label of FIG. 11, taken along line II-II of FIG. 11.
[0038] [0038]FIG. 13 is a perspective view of an apparatus for producing a folded label having an RF device incorporated therein according to another embodiment of the present invention.
[0039] [0039]FIG. 14 illustrates a RF label made according to the embodiment of FIG. 13.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0040] For a general understanding of the features of the present invention, reference is made to the drawings, wherein like reference numerals have been used throughout to identify identical or similar elements. FIG. 1 is a perspective view of an apparatus 10 for attaching a plurality of RF devices 20 to a carrier strip or tape 12 . Carrier 12 is made of a woven polyester tape. The apparatus of the embodiment of FIG. 4 includes carrier 12 , a THK linear track 14 , a bracket 16 , a 40 Khz ultrasonic welder 18 , and a solid surface 22 .
[0041] As carrier tape 12 advances it passes over support surface 22 . Carrier 12 can travel via a linear advance or other advance mechanism. At support surface 22 the RF devices or tags are inserted between surface 22 and tape 12 , such that the RF devices are located below strip 12 . The ultrasonic welder 18 is located above tape 12 . Welder 18 is mounted on linear track 14 and bracket 16 , such that the welder can be moved upward and downward to adhere the RF device to strip 12 . As shown in FIG. 2, ultrasonic welder 18 includes bar horn 24 , the face of which seals RF device 20 to strip 12 . For example, ultrasonic welder 18 has soundwaves traveling through it at a frequency of 40 KHz. However, the ultrasonic settings of welder 18 can be adjusted based upon the material of strip 12 . Moreover, the actuation speed of linear track 14 can be coordinated with the advance speed of strip 12 .
[0042] Referring to FIGS. 3 and 4, the front and back sides of strip 12 with RF devices 20 adhered thereto are illustrated. Strip 12 can have a width d 1 , of for example, 15.0 mm. The centerlines of consecutive RF devices are spaced by a distance d 2 . Distance d 2 can be 30.0 mm, for example. Moreover, RF devices 20 are orientated with carrier strip 12 such that an angle a therebetween is 90°.
[0043] As shown in FIGS. 3 and 4, one end of RF device 20 extends from edge 12 b of strip 12 . However, the opposite end of RF device 20 does not extend over edge 12 a of carrier strip 12 . The RF devices encapsulated in the labels can include scannable circuitry embedded in the labels. It should be appreciated that many arrangements of attachment are possible.
[0044] Referring to FIG. 5, a first embodiment of an apparatus for attaching RF devices to a woven label is shown. Carrier strip 12 having RF devices adhered thereto is mounted on a roller 26 . Folded ribbon 30 of material containing labels is advanced from a press station 32 via a drive roller 34 . The apparatus has two linear drive mechanisms. The first, which is part of the press station, is an uninterrupted linear advance, which maintains tension during folding. The second is an indexing mechanism. Regulating the tension of the ribbon of material is important during the folding process. In particular, the upper edge and the lower edge of the material must be maintained at essentially equal tensions. A centerline of the material is the main control for this adjustment. The centerline is preferably setup equal to the centerline of the press unit and the folding station. Raising or lowering the roll from this point can be done to equalize the tensions in the upper and lower edge of the material.
[0045] Folded ribbon of labels 30 can be composed of virtually any material that can be cut and pressed including a thermoplastic material (e.g., polyester), acetate, cotton, nylon, linen, paper, rayon and combinations thereof, in woven and non-woven form. Polyester is preferred. The labels can be printed or woven, however, woven is preferred.
[0046] It is preferred that the logo of the label is made such that it is 90 degrees from the typical orientation used in broadloom, needeloom or shuttleloom weaving of the woven labels. For woven labels this can be readily done on existing harness repeats. The change of orientation greatly reduces “window shading” (curling after laundering) and decreases shrinkage when the product is exposed to heat at temperatures above 275° F.
[0047] In the folding station (not shown) folded label ribbon 30 can be guided through a series of adjustable equalizing rollers (not shown) that make up the tension equalizer assembly to provide an even distribution of tension. After emerging from the equalizing rollers, the ribbon is guided over a folding rod (not shown).
[0048] For producing a centerfold label, the folding station comprises two folding lenses (not shown). Folding lenses are pivotably mounted on supports and can be adjusted vertically. The lenses are a caliper-like device comprising two adjustable jaws. The lenses restrain and guide the material into an even consistent fold. One lens can be a guiding lens used for making for slight adjustments before the material enters the other lens, the working lens that brings the ribbon to a fold. In certain situations a proper fold can be obtained using more or less that two lenses.
[0049] It is preferred that the distance along the x-axis on the lens be ½ of the loom cut width +1.5 mm or −1.5 mm depending on the thickness and stability of the material being processed. The y-axis distance should allow for even flow of material. Changing lenses to a larger or smaller diameter may be necessary for widths over 120 mm or below 50 mm.
[0050] Movement of the lens in the “+” x-axis direction will create a larger top fold. Movement of the lens in the “−” x-axis direction will create a larger bottom fold. Placement of the y-axis for both lens is along a centerline. If the material has a tendency to twist then an angle downward or upward may be set on either lens.
[0051] It is preferable that the location of folding rod (not shown) be kept in center with folding lenses along the centerline. The folding rod is square to the base. Material angle is kept from 5°-170°, more preferably 30°-90°. The distance from the folding rod to the press unit is dictated by the loom cut width of the material being folded. The wider the tape/ribbon cut, the further the folding rod is located from the press unit. The folded material exits the folding station and enters the press station. The press station subjects the folded material to both heat (100°-400° F.) and pressure. A range of pressure between 5-80 pounds of force is preferred. In one embodiment, the press unit includes a support frame upon which are movably affixed belt rolls about which is positioned a high temperature resistant endless conveyor belt. The belt may be driven at selected, controlled, constant speeds by known means such as an AC or DC electric drive motor and speed regulator or controller. Between the affixed belt rolls are a series of rollers, spring mounted to the support frame, upon which the top of the conveyor rides.
[0052] The speed of the press station motor can be trimmed with an ultrasonic range-finder that is wired into the motor controller inside the unit. A speed signal is sent to the servomotor. From this signal a calculation is made and held in memory. The ultra sonic range finder makes a reading of the slack of material as it travels between press station and cutting station. This is added to the number held in memory and this sum is sent to the belt drive motor to control belt speed.
[0053] The press station can have multiple heat zones that can be controlled separately. The first heat zone can be designed to carry most of the heat and the heat zones can be designed as a cool down area. The settings of the press station are dictated by the type of material being processed. Thicker materials require a higher press setting and more heat, while thinner materials require less.
[0054] The folded material travels though the press unit via a conveyer mechanism. It is this conveyor mechanism that provides a linear advance pulling the ribbon from the tension let off device through the folding station. Other mechanisms for linear advance can be used.
[0055] The folded pressed ribbon exits the press station and is led to the cutting station on a support plate. Upon advance of the material, downward pressure from the roll is dependent on material thickness, and structure. Thinner, looser structure materials require low pressure. Thicker and more stable structures of material require a higher downward pressure.
[0056] Referring once again to FIG. 5, a sensor 36 is used to monitor and control the slack of the folded ribbon of labels 30 between an applicator unit 40 , which will be described further herein, and drive roller 34 through a control unit (not shown). The speed of the applicator 40 is controlled to stay consistent with the advancing material and the delays set for cut time and acceleration and deceleration of the servo motor that turns drive roller 34 .
[0057] A roll of ribbon of material 36 is also advanced via drive roller 34 . Drive roller 34 pulls folded ribbon of labels 30 and fabric ribbon of material 36 forward and under a fiber optic eye 42 . To maintain the proper alignment for materials with logos and written instructions such as woven or printed labels, the fiber optic eye is used, which reads color contrast as material advances past its read point. When a registration point passes under the eye or when the eye sees a color change an immediate interrupt signal is sent to the controller, at this point the servo motor, via roller 34 , advances the material the distance set in the operator interface. The deceleration is calculated so that the material advance will be accurate to +−0.05 mm. At this point the material remains stopped for the cutting, e.g., knife delay time set on the operator interface. The material then advances and follows the same sequence above.
[0058] A typical setting for the advance is the width of the label (length along loom cut edge) minus 5 mm. This number may be adjusted to influence centering of the logo. Additional adjustment can be made if necessary.
[0059] At the stop, carrier strip 12 is advanced over a peeler 44 presenting the RF devices 20 to ribbon of material 36 . The carrier strip minus devices 20 is rewound unto roller 46 . Applicator 40 includes an anvil and attached piston 48 . Anvil 48 includes a vacuum device which attracts ribbon of material 36 . The piston activates an ultrasonic horn 50 which welds the RF device to ribbon of material 36 . The applicator unit is adjustable via a frame 52 to align with the logo on folded ribbon of labels 30 .
[0060] The ribbon of material 36 with the RF devices 20 mounted thereon is guided by roller 38 and drive roller 34 to cutting station 60 . The RF device is registered with the logo on the label ribbon by advance of both ribbons 30 , 36 through drive roller 34 and optic eye 42 .
[0061] The material is cut at cutting station 60 to form folded labels 70 using an ultrasonic system 62 comprising a horn 64 and an anvil 66 . For example, the ultrasonic horn 64 has sound waves moving through it at a frequency of 20-40 KHz. The residence of these waves can be magnified through proper booster and horn combination.
[0062] Anvil 66 is actuated at an adjustable pressure to collide with the horn. The material passes between the horn and the anvil and is exposed to very high-localized heat, cutting and sealing the material. The larger the radius on the anvil the larger the seal area and the more pressure required for a cut. The default delay time for the knife up is calculated and taken into account. For example, a typical delay is 70 ms, which may be adjusted if necessary to accomplish the desired results. Ultrasonic rotary dies can also be used.
[0063] The cutting station can utilize other known cutting techniques to subdivide the ribbon into individual labels. Such techniques include, for example, cold or hot shearing knives, hot fuse knives that squeeze off the product during cutting, extreme high mechanical pressure, high-pressure air, high-pressure water, laser cutting, rotary die cutters, and others. In the case of the fabric carrier, the fabric carrier is cut and bonded to the cut edges of the label. The fabric layer can be within a centerfold label, along the back of a centerfold label, along the front of a centerfold label along the back of an end fold label, along the front of an end fold label, along the front of an end fold label, or any of the above conditions on other labels processed on the equipment.
[0064] After cutting the finished label, the process proceeds to a packer (not shown). The packer then pushes the label into a packing box. Packing of the cut labels can also be accomplished by bagging or placing the goods in boxes through any number of methods including single column stacks in horizontal or vertical orientation, curved stacker frays, or magazine devices in a rotary or sliding configuration.
[0065] Unlike centerfold labels produced using traditional techniques, the centerfold label of the present invention has the front and back folds sealed together along an edge with the RF device therein. By using alternative folding stations, the apparatus of the present invention can be used to form other varieties of folded labels. For example, to form “end-fold” labels.
[0066] [0066]FIG. 6 illustrates another embodiment of the present invention wherein the RF device is adhered to the ribbon of labels prior to the folding step. In this embodiment, the roll of ribbon of labels 30 is advanced by two linear drive mechanisms. The first linear advance mechanism 72 is part of the press station and is an uninterrupted linear advance which maintains tension during folding. The second is an indexing mechanism. As in the previous embodiment, mechanism 72 can be a pair of drive rollers or other mechanically equivalent advance. Ribbon of labels 30 is advanced along guide rollers 38 pass optical eye 42 and an application unit 80 . Optical eye 42 provides the signal for the placement of the RF device as the ribbon of labels is in motion.
[0067] Application unit 80 includes a blower which blows the RF device 20 , such as an electronic article surveillance tag, onto ribbon of labels 30 . Blower 80 is commercially available through Label-Aire, Inc., Custom Label-Aire Model 2111M combination air blow left hand labeled. The devices 20 are supported on a roll of carrier strip 12 , as previously discussed herein. As in the embodiment of FIG. 5, after RF device 20 is applied to ribbon of labels 30 , the carrier strip 12 is separated therefrom by peeler 44 and rewound on roll 46 .
[0068] The ribbon of labels 30 with RF devices 20 thereon passes through press unit 32 ′ which adheres the RF devices to ribbon of labels 30 . The ribbon of labels 30 then passes into the folding station 74 where the ribbon is folded, as previously set forth herein. After folding, the ribbon can pass to either a cutting device or rolled into a roll for further processing remote from the apparatus.
[0069] A label made according to the method and apparatus whereby the RF device is not separated from the carrier strip is illustrated in FIGS. 8 - 10 . The label is unique in that the cut sides are bonded and sealed along an edge. At the cut, the carrier is bonded to the edges of the individual RF label upon separation of the label from the ribbon of labels. As noted above, the resultant labels have a unique smooth feel based upon the process used to make them. Furthermore, thermoplastic ribbon of labels, preferably a woven polyester, is subdivided using an ultrasonic system as part of the claimed apparatus, the labels are unique in that the cut sides are bonded or welded together. As noted above, this bonding not only prevents the label from being skewed when sewed into a garment, but also provides the edges with a generally scratchless feel.
[0070] The apparatus of the invention is particularly suited for insertion of devices such as security and inventory control devices, e.g., radio frequency inventory devices (RFID) tags, into labels. RFIDs are known in the art and include that disclosed in U.S. Pat. Nos. 5,874,902; 5,874,896; 5,785,181; and 5,745,036. Such devices can be inserted at a number of locations. By using an ultrasonic cutting system, these devices can be sealed into the bonded top and bottom edges of the material. This will cause the label to be destroyed if the device is removed; thus guaranteeing the tag and label stay as one during processing. At one location, the folded material is opened and the device is inserted at desired positions. At another location, adhesive backed devices are placed on the material before folding. Edge sealing can be achieved with these methods as well.
[0071] The RFID tag can include a scannable circuit board chip. The RFID technology will allow a RF label to be read or written to. The ability to write to the RF labels enables users to keep and update a database without the end user being able to alter the information on the embedded circuit board. In addition, the identification information may be reused and written over.
[0072] Look-up databases can be readily available to facilitate quick access to the information embedded on the RF labels. Moreover, lost or stolen items having the RF labels can be reunited with its owner or place of origin.
[0073] The scannable RF labels enables tracking of inventory, pricing and place of origin, without necessitating human intervention to research such information. The programmable and read-only scannable circuit boards cannot be altered or read without a programmer or reader. The RFID system typically consist of one or more transceivers (exciters) and one or more tags. An RFID tag is an electronic device that generally incorporates a specific and unique identification number, where the number may be read by a RF transceiver (transmitter/receiver) system. The RFID tags may acquire energy from the incident radio frequency field or powered by a battery.
[0074] RFID tags typically consists of an antenna or a coil, to collect RF energy, and an integrated circuit (IC) which contains identification code or other information in its on-chip memory. Attaching a RFID tag to a label enables the item to be located and identified with the aid of an RF interrogation system. As such, an interrogation system is able to identify information associated with the RFID labels as set forth in the present invention.
[0075] Commercially available RFID tags generally operate at low frequencies, typically below 1 Mhz. Although lower frequency devices are more common, a wide range of high frequencies are available, for example, 13.56 Mhz, 915 Mhz, 2.45 Ghz and 5.6 Ghz. Low frequency tags usually employ a multi-turn coil resulting in a tag having a thickness much greater than a standard sheet of paper. 2.45 Ghz and 5.6 Ghz can be done in a single turn or as a die pole antenna. High frequency passive RFID tags, which operate at around 2.54 Ghz, typically consist of a single turn, flat antenna, printed onto a flat single layer sheet of plastic or paper.
[0076] The combination of the folded labels with a RF device in the present invention allows for locating and tracking of items, detecting items and reporting of pricing, for example. This ability to read RF labels from codes may be utilized, for example, as the items having the RF labels leave predetermined areas and pass through an exit.
[0077] Referring to the apparatus of FIG. 7, the RF devices 20 are not separated from carrier strip 12 but inserted into a label while on strip 12 . Carrier strip 12 together with ribbon material 30 are advanced by drive roller 34 past optic eye 42 to ultrasonic cutting station 62 where the labels can be cut.
[0078] Such a center fold label is illustrated in FIGS. 8 - 10 . Label 70 with the RF device 20 and carrier strip 12 is disposed in folded ribbon of labels 30 . In FIG. 8, a portion of the material is pulled back showing device 20 and a portion of the carrier strip 12 to which it is mounted. The edge 12 a of strip 12 is located at the folded edge 31 of the ribbon material. In the assembled state, as shown in FIGS. 9 and 10, the carrier strip is bonded into the inside edges 29 of the label by the ultrasonic cutting device of the present invention.
[0079] [0079]FIG. 11 is a perspective view of an end fold label made according to the apparatus and method of FIG. 7. As shown, label of ribbons 30 , carrier strip 12 and RF device 20 disposed therebetween are subdivided along edge 27 into individual labels. Referring to FIG. 12, the ends of label 30 are folded over strip 12 .
[0080] [0080]FIG. 13 illustrates an apparatus for applying a radio frequency device into the ribbons of labels and registering the cut of the ribbons of labels by sensing the edge or part of the RF device disposed inside the folded ribbon. As illustrated, a length of the ribbon of labels 30 , RF devices 20 and carrier strip 12 passes through press station 32 , past drive rollers 34 , past sensor 100 and light source 101 , to ultrasonic horn 64 and anvil 66 . The RF device disposed inside of the folded ribbon is detected by optical sensor 100 via light source 101 , which shines light through the ribbon of labels, but does not shine light through the device embedded therein. The advance mechanism indexes the ribbon by detection of the RF device, not by the logo or text on the front of the ribbon. As the device passes by light sensor 101 , the light will go out until the RF device passes. Optical sensor 100 senses the absence of light as the RF device passes. Alternatively, a sensor that would sense the metal component in the RF device could also be used to sense the edge or part of the RF device inside the folded ribbon.
[0081] A label made according to the method and apparatus of FIG. 13, is shown in FIG. 14. As shown, the design or logo 102 can be repeated anywhere on the label and need not be centered with regard to cut line C L . In the case of a “cut it out before you wear” label as shown in FIG. 14, the text can be written in succession on the label. Subdivision of the label does not depend on the position of the text, but only on the position of the RF device therein. The same applies to a permanent label.
[0082] The apparatus of the present invention can be modified at any point to include various accessories. A vision system can be included to inspect the logos and image on the material as it passes. Labels with errors are detected and removed automatically.
[0083] Additionally, the apparatus can be modified such that the cutting station the corners of the cut material are removed to provide for heightened comfort. Further, the apparatus can be modified to ultrasonically seal the open loom cut edge giving a centerfold label, for example, three ultrasonically sealed edges and one folded edge.
[0084] Specially, it will be understood that the instant invention applies to all various types of label types and is not intended to be limited by the manner in which the labels are developed.
[0085] The apparatus of this present invention may have several different folding stations or interchangeable folding stations, thus allowing the user to select different fold configurations. Alternatively, there may be a series of components that function in one overall device. The press and cutting stations are electronically linked by means of at least one sensor to coordinate operation.
[0086] Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims. | The present invention includes a method for producing individual folded labels incorporating a radio frequency device, the method comprising the steps of providing a ribbon of labels containing a woven logo or text. A carrier strip with a plurality of radio frequency devices spaced thereon is provided and the plurality of radio frequency devices are joined to the ribbon of labels. The ribbon of labels is then folded so as to form at least one folded portion. The folded ribbon is subjected to sufficient heat and pressure to set the at least one folded portion. The ribbon of labels is subdivided into individual folded labels. The present invention also relates to a label-making apparatus including a dispenser for a carrier strip having a plurality of radio frequency devices disposed thereon at spaced intervals. A mechanism linearly advances a ribbon of labels, the ribbon of labels containing a woven logo or text. Means join the plurality of radio frequency devices with the ribbon of labels. A cutting station subdivides an individual label from the ribbon of labels and plurality of radio frequency devices. A sensor in communication with the linear advance mechanism controls the advance of a length of the ribbon of labels to provide proper spacing between the radio frequency devices, cut-edges and a logo on the label. The sensor can sense the position of the RF device or the logo or text of the ribbon of labels. | 1 |
BACKGROUND OF THE INVENTION
1. Field Of The Invention
This invention relates to an improved waterproofing laminate and, more specifically, it relates to such laminates which are particularly useful in connection with waterproofing of building surfaces such as roofs, floors and other surfaces wherein it is desired to resist penetration of water or water vapor.
2. Description Of The Prior Art
It has been known to employ in various roofing systems built-up roofing. Such systems may include a layer of bituminous roofing felt, a bitumen layer coated on one or both surfaces of the felt and a material such as gravel, sand or the like which is deposited on an exposed bitumen layer. Among the problems found in such systems is that they require extensive field labor, tend to lack uniformity in respect of structural nature and effectiveness from zone to zone and may not perform effectively under a wide variety of climatic conditions.
It has also been known to employ waterproof sheeting which has been applied to a substrate such as a roof substrate using molten bitumen or cold applied bituminous adhesives. Among the problems with such approaches is the failure of the elastomeric sheeting to maintain dimensional stability and avoid wrinkling when bonded with hot bitumen. Also, depending upon the conditions at the time of application the adhesive bond can vary in effectiveness substantially. On slopes greater than about 10 degrees it is generally necessary to employ mechanical fasteners to secure the membrane in place. Such membranes must generally be left exposed for periods in excess of about 30 days before painting in order to permit the adhesive to cure completely. Such adhesively securd elastomeric sheetings also can generally not be applied directly to insulation, wood, metal, concrete and other materials. Also, in warm weather the temperature of the roof can reach such a level that the adhesive liquifies.
It has been known to provide laminated roofing membranes which contain bitumen coated layers and compound bitumen coated layers. See U.S. Pat. Nos. 4,055,453 and 4,091,135 the disclosures of which are expressly incorporated herein by reference.
It has been known that elastomeric materials such as natural or synthetic rubber and bituminous materials tend to be incompatible and that bituminous materials will tend to attack and degrade elastomeric materials.
There remains, therefore, a very real and substantial need for a waterproofing laminate which will provide effective, dependable waterproofing to a roof, floor, below grade installation or other installaton making waterproofing characteristics desirable or necessary.
SUMMARY OF THE INVENTION
The present invention has solved the above-described problem. A waterproofing laminate comprises a reinforcing sheet, first bitumen layers secured to the surfaces of the reinforcing sheets, first and second compound bitumen layers secured to the first and second bitumen layers, an elastomeric sheet secured to one of the compound bitumen layers and a release sheet secured to the other. Removal of the release sheet permits the waterproofing laminate to be secured to a surface to be protected.
It is an object of the present invention to provide an improved waterproofing laminate which will resist undesired penetration of water and water vapor therethrogh.
It is another object of the present invention to provide a waterproofing laminate which will resist shrinking and wrinkling during application and following application.
It is a further object of the present invention to provide an assembly wherein factory labor is substituted to a major extent for field labor.
It is a further object of the invention to provide an assembly wherein securement of the waterproofing laminate will not alter the effectiveness as a result of the climatic conditions under which the installation is made.
It is a further object of the present invention to provide such an assembly which can be secured directly to a wide variety of materials, can be painted promptly after installation and need not be secured by mechanical fasteners on installations which slope.
It is a further object of the present invention to provide an adhesive which will not liquify under extreme high temperatures.
It is yet another object of the present invention to provide a multi-layered reinforced bituminous membrane which will resist deterioration under the influence of a wide variety of chemical elements, will have tensile and elongation properties such that wide variations in temperature and physical movement of building components will not destroy its effectiveness.
These and other objects of the invention will be more fully undersood from the following description of the invention on reference to the illustrations appended hereto.
BRIEF DESCRIPTION OF THE DRAWING
The drawing is a somewhat schematic cross-sectional illustration of a laminate of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As is shown in the FIGURE, a reinforcing sheet 2 has layers of bitumen 4, 6 secured to opposed surfaces thereof. Layers of compound bitumen 8, 10 are secured respectively to the bitumen layers 4, 6. An elastomeric sheet 12 is secured to compound bitumen layer 10 and release sheet 14 is secured to compound bitumen layer 8. It is contemplated that the elastomeric sheet 12 will be exposed to the elements when the laminate is secured to a roof, floor or other building component. Application to the surface is made by removing release sheet 14 thereby exposing compound bitumen layer 8 which may then serve as an adhesive to bond the laminate to the surface to be protected. The elastomeric sheet preferably has certain characteristics including properties which resist bitumen attack. A suitable sheet for this purpose is that disclosed in U.S. Pat. No. 4,458,043 the disclosure of which is expressly incorporated herein by reference.
In general, it will be preferred that the elastomeric sheet 12 contain a material selected from the group consisting of polyisobutylene, chlorinated polyethylene, natural rubber, polyvinyl chloride and ethylene vinyl acetate. Ethylene propylene diene copolymer may also be used. A specifically preferred formulation for the elastomeric sheet 12 includes about 10 to 40 percent by weight of unplasticized polyvinyl chloride, about 10 to 40 percent by weight of an ethylene vinyl acetate carbon monoxide terpolymer and about 5 to 35 percent of coal tar pitch. The elastomeric sheet may also contain up to about 30 percent of particulate filler, up to about 25 percent of fibrous filler and up to about 15 percent primary or secondary plasticizer with or without up to about 10 percent of processing aids or stabilizers.
The amount of PVC is preferably in the range of about 20 to 30 percent by weight of the entire composition and may advantageously be provided as a suspension or emulsion grade of polyvinyl chloride. The ethylene vinyl acetate carbon monoxide terpolymer may contain about 15 to 85 percent ethylene, about 5 to 60 percent vinyl acetate and about 0.5 to 30 percent carbon monoxide, all on a weight basis. A suitable terpolymer for use in this context is that marketed by du Pont de Nemours E.I. & Company under the trade designation "Elvaloy" with the preference being for "Elvaloy 742".
With respect to the coal tar pitch constituent, it may be provided as such or in admixture with bitumen of natural or synthetic origin such as an unmodified or modified bitumen from the primary or secondary refining of petroleum. Any bitumen present in the coal tar pitch is preferably present in an amount of less than about 30 percent by weight of the pitch/bitumen mixture. The pitch preferably has a softening point (as determined by the ring and ball method) in the range of about 80 degrees C. to 150 degrees C. and preferably around 105 degrees C. It may preferably be that known as "electrode pitch".
The elastomeric sheet 12 preferably contains particulate and fibrous fillers. Among the suitable particulate fillers are reinforcing fillers such as carbon black, silica, zinc oxide, phenolic resin and magnesium carbonate. Among the nonreinforcing fillers, those preferred are calcium carbonate (whiting), barium sulphate, hydrated aluminum silicate, china clay and magnesium silicate. The total amount of particulate filler is preferably up to about 30 percent weight percent based upon total composition with a specific preference being for up to about 20 percent weight percent. Preferred fibrous fillers are natural fibers including inorganic or mineral fibers, wool and cotton, as monofilament or yarn and synthetic fibers, for example, nylon and polyester provided as monofilament or yarn. The fibrous fillers may conveniently be comminuted waste conveyor belting or other suitable waste fiber, if desired.
A suitable plasticizer for use in the polyvinyl chloride is preferably incorporated in the elastomeric sheet 12. It may be, for example, a phthalate ester, an ester of sebacic or adipie acid, a phosphate ester or oxidized soya bean oil. The plasticizer is preferably present in an amount of not more than about 8 percent by weight of the total composition.
Among the processing aids preferably employed are well known internal and external lubricants which have conventionally been employed in connection with polyvinyl chloride compounding. The composition is preferably provided with an amount of stabilizer to prevent degradation of the polyvinyl chloride or ethylene vinyl acetate carbon monoxide terpolymer during high temperature processing. The selection and quantity of such stabilizers are well known to those skilled in the art.
In making the material for use in the elastomeric sheet 12, the materials may be processed by mixing in a compounding roll mill such as a Buss Ko Kneader or a Banbury type mixer and may be converted to sheet form by calendering or extrusion.
The elastomeric sheet 12 may comprise or be laminated with a reinforcing fabric such as a woven or non-woven polyester or glass scrim. A suitable thickness for the sheeting is about 0.0020 of an inch to 0.0060. The reinforcing sheet 2 may be of the type disclosed in U.S. Pat. Nos. 4,055,453 and 4,091,135.
The reinforcing sheet 2 may be selected from those which have come into common use for the ordinary bituminous roof membrane such as a class fleece or non-woven fabric composed of synthetic fiber as well as previously known material such as paper, felt, fabric or cloth composed of organic or inorganic fiber such as, for example, rag felt, asbestos felt, cotton fabric or jute cloth. Generally when fibrous sheets are used they are impregnated with molten bitumen in order to seal the vids therein before the reinforcing sheet 2 is subjected to coating with molten bitumen. The reinforcing sheet 2 may also be provided from synthetic polymer film or metal foil such as aluminum foil or copper foil. When such film or foil is used the pre-impregnation treatment with bitumen is not necessary. If desired, suitable physical or chemical treatment as by sandblasting, etching or the like may be provided to establish a good affinity with bitumen before subjecting the reinforcing sheet 2 to a layer of molten bitumen.
The reinforcing sheet 2 is covered on one surface or both surfaces with bitumen and all or part of the bitumen coated layer is laminated with compound bitumen that may be denatured bitumen prepared to impart high tackiness at ambient temperature as a result of blending of the same with natural or synthetic rubber or natural or synthetic resins or both. See U.S. Pat. No. 4,039,706, the disclosure of which is incorported herein by reference.
It is preferred that the layers of bitumen and layers of compound bitumen be applied in the form of a coating with the former having a thickness of about 0.001 to 0.015 inch and preferably about 0.0025 to 0.007 inch and the latter having a thickness of about 0.001 to 0.015 inch and preferably 0.0025 to 0.007 inch.
The blending materials should be selected so as to effect a denaturing and enhancement of properties of the bitumen particularly in respect to temperature susceptibility. With respect to rubber, the preferred materials for use for this purpose are vulcanized or nonvulcanized rubber composed of various types of synthetic rubber such as styrene-butadiene rubber, acrylonitrile-butadiene rubber, chloroprene rubber, butadiene rubber, isoprene rubber, butyl rubber, ethylenepropylene rubber, ethylene-propylene diene mar, polyisobutylene, chlorinated polyethylene and natural rubber. Among the natural or synthetic resins preferred for this purpose are rosin, rosin derivatives such as estergum, tall oil, cumarone-indene resin, petroleum resins and polyolefin such as polybutene. It is preferred that the total amount of rubber, resin or combinations of both present in the compound bitumen layer be around 15 to 50 percent by weight.
If desired, these rubber and resin blending materials may be partially substituted for by animal or vegetable oils and fats as these oils and fats also are effective for increasing the tackiness of the bitumen. Among the oils and fats which are suitable for this purpose are animal oils and fats such as fish oil, whale oil, beef tallow and the like as well as vegetable oil such as linseed oil, tung oil, sesame oil, cottonseed oil, soyabeam oil, olive oil, castor oil and the like. They also may include materials such as stand oil, oxidized oil and boiled oil made therefrom as well as fatty acid pitch and the like. The quantity of these oils and fats is preferably less than 50 percent by weight of the total quantity of rubber and/or resin and oils and fats added.
Also, if desired, a softener such as petroleum oil, or a filler such as mica powder can be incorporated into the compound bitumen.
Release sheet 14 is provided over one surface of the compound bitumen 8 in order to protect it from inadvertent contact with surfaces other than the surface sought to be protected. The release sheet 14 may advantageously be composed of cellophane, polyvinyl alcohol film or aluminum foil. It may also take the form of a treated sheet such as film, foil, paper and the like subjected to surface treatment as by coating or impregnated with synthetic resins having high releasing property such as silicone resin, flourine-containing resin and polyvinylidene chloride.
EXAMPLE
In order to provide a further understanding of the invention, an example will be considered. A reinforcing sheet 2 consisting of a biaxial crosslaminated polyethylene film is unrolled from a roll and passes through coating rollers where the sheet is coated totally or partially on both sides with a straight run of oxidized bitumen at 220 degrees C. to a thickness of about 2/3 mm. Two release sheets such as paper are separately conducted to respectively independent roller coater assemblies where a molten compound containing, for example, about 20 percent by weight of rubber and/or resins and is maintained at about 200 degrees C. is provided. The release paper is coated on the releasable face of each releasable sheet with the compound bitumen so as to form a coated layer of a suitable thickness of about, for example, 0.3 to 0.5 mm. The reinforcing sheet is coated with bitumen on both surfaces and the bitumen surfaces of the coated reinforcing sheet placed in contact with the compound bitumen coated surface of a release sheet to thereby establish a compound bitumen-bitumen interface. The release paper is then removed from one surface and the elastomeric sheet is subsequently adhered to that surface by interfacing the elastomeric sheet with the compound bitumen on that surface. The entire assembly is then subjected to a pressure of about 50 psi by passing it through pressure rollers.
In general, it will be preferred that the bitumen and compound bitumen layers be applied continuously to the respective surfaces in order to provide uniform laminate.
In applying the laminate to a roof, floor or other structure one need merely remove the release paper 14 thereby exposing the compound bitumen layer 8 permitting the adhesive compound bitumen 8 to be applied in surface-to-surface contact with the surface to be protected. With the application of slight pressure, the installation is complete.
It will be appreciated that the membrane laminate of the present invention provides an effective means for substituting factory labor for field labor in producing a product of desirable uniform characteristics eliminating the numerous undesirable aspects of the prior art products and methods as discussed hereinbefore.
Whereas particular embodiments of the invention have been described above for purposes of illustration it will be evident to those skilled in the art that numerous variations of the details may be made without departing from the invention as defined in the appended claims. | A waterproofing laminate suitable for use in roofs, floors or other surfaces where waterproofing is desired contains a reinforcing sheet, first and second bitumen layers secured to opposite surfaces of the reinforcing sheet, first and second compound bitumen layers secured to the bitumen layers, an elastomeric sheet secured to the first compound bitumen layer and a release sheet secured to the second compound bitumen layer. Certain preferred materials for use in the laminate are recited. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of International Application PCT/NL01/00697, filed Sep. 21, 2001, designating the United States, published in English Mar. 28, 2002, as WO 02/024906 A1 and subsequently published with corrections Jan. 23, 2003, as WO 02/024906 C2, the contents of both of which are incorporated by this reference.
TECHNICAL FIELD
[0002] The invention relates to the field of gene therapy.
BACKGROUND
[0003] Given the rapid advances of human genome research, professionals and the public expect that the near future will bring us, in addition to understanding of disease mechanisms and refined and reliable diagnostics, therapies for many devastating genetic diseases.
[0004] While it is hoped that for some (e.g., metabolic) diseases, the improved insights will bring easily administrable small-molecule therapies, it is likely that in most cases one or another form of gene therapy will ultimately be required, i.e., the correction, addition or replacement of the defective gene product.
[0005] In the past few years, research and development in this field have highlighted several technical difficulties which need to be overcome, e.g., related to the large size of many genes involved in genetic disease (limiting the choice of suitable systems to administer the therapeutic gene), the accessibility of the tissue in which the therapeutic gene should function (requiring the design of specific targeting techniques, either physically, by restricted injection, or biologically, by developing systems with tissue-specific affinities) and the safety to the patient of the administration system. These problems are to some extent interrelated, and it can be generally concluded that the smaller the therapeutic agent is, the easier it will become to develop efficient, targetable and safe administration systems.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention addresses this problem by inducing so-called exon-skipping in cells. Exon-skipping results in mature mRNA that does not contain the skipped exon and thus, when the exon codes for amino acids, can lead to the expression of an altered product. Technology for exon-skipping is currently directed toward the use of so-called “Anti-sense Oligonucleotides” (AONs).
[0007] Much of this work is done in the mdx mouse model for Duchenne muscular dystrophy (DMD). The mdx mouse, which carries a nonsense mutation in exon 23 of the dystrophin gene, has been used as an animal model of Duchenne muscular dystrophy. Despite the mdx mutation, which should preclude the synthesis of a functional dystrophin protein, rare, naturally occurring dystrophin-positive fibers have been observed in mdx muscle tissue. These dystrophin-positive fibers are thought to have arisen from an apparently naturally occurring exon-skipping mechanism, either due to somatic mutations or through alternative splicing.
[0008] AONs directed to, respectively, the 3′ and 5′ splice sites of introns 22 and 23 in dystrophin pre-mRNA have been shown to interfere with factors normally involved in removal of intron 23 so that exon 23 was also removed from the mRNA (Wilton, 1999). In a similar study, Dunckley et al. (1998) showed that exon skipping using AONs directed to 3′ and 5′ splice sites can have unexpected results. They observed skipping of not only exon 23 but also of exons 24-29, thus resulting in an mRNA containing an exon 22-exon 30 junction.
[0009] The underlying mechanism for the appearance of the unexpected 22-30 splicing variant is not known. It could be due to the fact that splice sites contain consensus sequences leading to promiscuous hybridization of the oligos used to direct the exon skipping. Hybridization of the oligos to other splice sites than the sites of the exon to be skipped of course could easily interfere with the accuracy of the splicing process. On the other hand, the accuracy could be lacking due to the fact that two oligos (for the 5′ and the 3′ splice site) need to be used. Pre-mRNA containing one but not the other oligo could be prone to unexpected splicing variants.
[0010] To overcome these and other problems, the present invention provides a method for directing splicing of a pre-mRNA in a system capable of performing a splicing operation comprising contacting the pre-mRNA in the system with an agent capable of specifically inhibiting an exon inclusion signal of at least one exon in the pre-mRNA, the method further comprising allowing splicing of the pre-mRNA. Interfering with an exon inclusion signal (EIS) has the advantage that such elements are located within the exon. By providing an antisense oligo for the interior of the exon to be skipped, it is possible to interfere with the exon inclusion signal, thereby effectively masking the exon from the splicing apparatus. The failure of the splicing apparatus to recognize the exon to be skipped thus leads to exclusion of the exon from the final mRNA.
[0011] The present invention does not interfere directly with the enzymatic process of the splicing machinery (the joining of the exons). It is thought that this allows the method to be more robust and reliable. It is thought that an EIS is a particular structure of an exon that allows splice acceptor and donor to assume a particular spatial conformation. In this concept, it is the particular spatial conformation that enables the splicing machinery to recognize the exon. However, the invention is certainly not limited to this model.
[0012] It has been found that agents capable of binding to an exon can inhibit an EIS. Agents may specifically contact the exon at any point and still be able to specifically inhibit the EIS. The mRNA may be useful in itself. For instance, production of an undesired protein can be at least in part reduced by inhibiting inclusion of a required exon into the mRNA. A preferred method of the invention further comprises allowing translation of mRNA produced from splicing of the pre-mRNA. Preferably, the MRNA encodes a functional protein. In a preferred embodiment, the protein comprises two or more domains, wherein at least one of the domains is encoded by the mRNA as a result of skipping of at least part of an exon in the pre-mRNA.
[0013] Exon skipping will typically, though not necessarily, be of relevance for proteins in the wild type configuration, having at least two functional domains that each performs a function, wherein the domains are generated from distinct parts of the primary amino acid sequence. Examples are, for instance, transcription factors. Typically, these factors comprise a DNA binding domain and a domain that interacts with other proteins in the cell. Skipping of an exon that encodes a part of the primary amino acid sequence that lies between these two domains can lead to a shorter protein that comprises the same function, at least in part. Thus, detrimental mutations in this intermediary region (for instance, frame-shift or stop mutations) can be at least in part repaired by inducing exon skipping to allow synthesis of the shorter (partly) functional protein.
[0014] Using a method of the invention, it is also possible to induce partial skipping of the exon. In this embodiment, the contacting results in activation of a cryptic splice site in a contacted exon. This embodiment broadens the potential for manipulation of the pre-mRNA leading to a functional protein. Preferably, the system comprises a cell. Preferably, the cell is cultured in vitro or in the organism in vivo. Typically, though not necessarily, the organism comprises a human or a mouse.
[0015] In a preferred embodiment, the invention provides a method for at least in part decreasing the production of an aberrant protein in a cell, the cell comprising pre-mRNA comprising exons coding for the protein, the method comprising providing the cell with an agent capable of specifically inhibiting an exon inclusion signal of at least one of the exons, the method further comprising allowing translation of mRNA produced from splicing of the pre-mRNA.
[0016] Any agent capable of specifically inhibiting an exon exclusion signal can be used for the present invention. Preferably, the agent comprises a nucleic acid or a functional equivalent thereof. Preferably, but not necessarily, the nucleic acid is in single-stranded form. Peptide nucleic acid and other molecules comprising the same nucleic acid binding characteristics in kind, but not necessarily in amount, are suitable equivalents. Nucleic acid or an equivalent may comprise modifications to provide additional functionality. For instance, 2′-O-methyl oligoribonucleotides can be used. These ribonucleotides are more resistant to RNAse action than conventional oligonucleotides.
[0017] In a preferred embodiment of the invention, the exon inclusion signal is interfered with by an antisense nucleic acid directed to an exon recognition sequence (ERS). These sequences are relatively purine-rich and can be distinguished by scrutinizing the sequence information of the exon to be skipped (Tanaka et al., 1994, Mol. Cell. Biol. 14, p. 1347-1354). Exon recognition sequences are thought to aid inclusion into mRNA of so-called weak exons (Achsel et al., 1996, J. Biochem. 120, p.53-60). These weak exons comprise, for instance, 5′ and or 3′ splice sites that are less efficiently recognized by the splicing machinery. In the present invention, it has been found that exon skipping can also be induced in so-called strong exons, i.e., exons which are normally efficiently recognized by the splicing machinery of the cell. From any given sequence, it is (almost) always possible to predict whether the sequence comprises putative exons and to determine whether these exons are strong or weak. Several algorithms for determining the strength of an exon exist. A useful algorithm can be found on the NetGene2 splice site prediction server (Brunak, et al., 1991, J. Mol. Biol. 220, p. 49-65). Exon skipping by a means of the invention can be induced in (almost) every exon, independent of whether the exon is a weak exon or a strong exon and also independent of whether the exon comprises an ERS. In a preferred embodiment, an exon that is targeted for skipping is a strong exon. In another preferred embodiment, an exon targeted for skipping does not comprise an ERS.
[0018] Methods of the invention can be used in many ways. In one embodiment, a method of the invention is used to at least in part decrease the production of an aberrant protein. Such proteins can, for instance, be onco-proteins or viral proteins. In many tumors, not only the presence of an onco-protein but also its relative level of expression has been associated with the phenotype of the tumor cell. Similarly, not only the presence of viral proteins but also the amount of viral protein in a cell determines the virulence of a particular virus. Moreover, for efficient multiplication and spread of a virus, the timing of expression in the life cycle and the balance in the amount of certain viral proteins in a cell determines whether viruses are efficiently or inefficiently produced. Using a method of the invention, it is possible to lower the amount of aberrant protein in a cell such that, for instance, a tumor cell becomes less tumorigenic (metastatic) and/or a virus-infected cell produces less virus.
[0019] In a preferred embodiment, a method of the invention is used to modify the aberrant protein into a functional protein. In one embodiment, the functional protein is capable of performing a function of a protein normally present in a cell but absent in the cells to be treated. Very often, even partial restoration of function results in significantly improved performance of the cell thus treated. Due to the better performance, such cells can also have a selective advantage over unmodified cells, thus aiding the efficacy of the treatment.
[0020] This aspect of the invention is particularly suited for the restoration of expression of defective genes. This is achieved by causing the specific skipping of targeted exons, thus bypassing or correcting deleterious mutations (typically stop-mutations or frame-shifting point mutations, single- or multi-exon deletions or insertions leading to translation termination).
[0021] Compared to gene-introduction strategies, this novel form of splice-modulation gene therapy requires the administration of much smaller therapeutic reagents, typically, but not limited to, 14-40 nucleotides. In a preferred embodiment, molecules of 14-25 nucleotides are used since these molecules are easier to produce and enter the cell more effectively. The methods of the invention allow much more flexibility in the subsequent design of effective and safe administration systems. An important additional advantage of this aspect of the invention is that it restores (at least some of) the activity of the endogenous gene, which still possesses most or all of its gene-regulatory circuitry, thus ensuring proper expression levels and the synthesis of tissue-specific isoforms.
[0022] This aspect of the invention can in principle be applied to any genetic disease or genetic predisposition to disease in which targeted skipping of specific exons would restore the translational reading frame when this has been disrupted by the original mutation, provided that translation of an internally slightly shorter protein is still fully or partly functional. Preferred embodiments for which this application can be of therapeutic value are: predisposition to second hit mutations in tumor suppressor genes, e.g., those involved in breast cancer, colon cancer, tuberous sclerosis, neurofibromatosis etc., where (partial) restoration of activity would preclude the manifestation of nullosomy by second hit mutations and thus would protect against tumorigenesis. Another preferred embodiment involves the (partial) restoration of defective gene products which have a direct disease causing effect, e.g., hemophilia A (clotting factor VIII deficiency), some forms of congenital hypothyroidism (due to thyroglobulin synthesis deficiency) and Duchenne muscular dystrophy (DMD), in which frame-shifting deletions, duplications and stop mutations in the X-linked dystrophin gene cause severe, progressive muscle degradation. DMD is typically lethal in late adolescence or early adulthood, while non-frame-shifting deletions or duplications in the same gene cause the much milder Becker muscular dystrophy (BMD), compatible with a life expectancy between 35-40 years to normal. In the embodiment as applied to DMD, the present invention enables exon skipping to extend an existing deletion (or alter the MRNA product of an existing duplication) by as many adjacent exons as required to restore the reading frame and generate an internally slightly shortened, but still functional, protein. Based on the much milder clinical symptoms of BMD patients with the equivalent of this induced deletion, the disease in the DMD patients would have a much milder course after AON-therapy.
[0023] Many different mutations in the dystrophin gene can lead to a dysfunctional protein. (For a comprehensive inventory see http://www.dmd.nl, the internationally accepted database for DMD and related disorders.) The precise exon to be skipped to generate a functional dystrophin protein varies from mutation to mutation. Table 1 comprises a non-limiting list of exons that can be skipped and lists for the mentioned exons some of the more frequently occurring dystrophin gene mutations that have been observed in humans and that can be treated with a method of the invention. Skipping of the mentioned exon leads to a mutant dystrophin protein comprising at least the functionality of a Becker mutant. Thus, in one embodiment, the invention provides a method of the invention wherein the exon inclusion signal is present in exon numbers 2, 8, 19, 29, 43, 44, 45, 46, 50, 51, 52 or 53 of the human dystrophin gene. The occurrence of certain deletion/insertion variations is more frequent than others. In the present invention, it was found that by inducing skipping of exon 46 with a means or a method of the invention, approximately 7% of DMD-deletion containing patients can be treated, resulting in the patients to comprise dystrophin-positive muscle fibers. By inducing skipping of exon 51, approximately 15% of DMD-deletion containing patients can be treated with a means or method of the invention. Such treatment will result in the patient having at least some dystrophin-positive fibers. Thus, with either skipping of exon 46 or 51 using a method of the invention, approximately 22% of the patients containing a deletion in the dystrophin gene can be treated. Thus, in a preferred embodiment of the invention, the exon exclusion signal is present in exon 46 or exon 51. In a particularly preferred embodiment, the agent comprises a nucleic acid sequence according to hAON#4, hAON#6, hAON#8, hAON#9, hAON#11 and/or one or more of hAON#21-30 or a functional part, derivative and/or analogue of the hAON. A functional part, derivative and/or analogue of the hAON comprises the same exon skipping activity in kind, but not necessarily in amount, in a method of the invention.
TABLE 1 Exon to be Therapeutic for DMD-deletions Frequency in skipped (exons) http://www.dmd.nl (%) 2 3-7 2 8 3-7 4 4-7 5-7 6-7 43 44 5 44-47 44 35-43 8 45 45-54 45 18-44 13 46-47 44 46-48 46-49 46-51 46-53 46 45 7 50 51 5 51-55 51 50 15 45-50 48-50 49-50 52 52-63 52 51 3 53 53-55 53 45-52 9 48-52 49-52 50-52 52
[0024] It can be advantageous to induce exon skipping of more than one exon in the pre-mRNA. For instance, considering the wide variety of mutations and the fixed nature of exon lengths and amino acid sequence flanking such mutations, the situation can occur that for restoration of function more than one exon needs to be skipped. A preferred but non-limiting example of such a case in the DMD deletion database is a 46-50 deletion. Patients comprising a 46-50 deletion do not produce functional dystrophin. However, an at least partially functional dystrophin can be generated by inducing skipping of both exon 45 and exon 51. Another preferred but non-limiting example is patients comprising a duplication of exon 2. By providing one agent capable of inhibiting an EIS of exon 2, it is possible to partly skip either one or both exons 2, thereby regenerating the wild-type protein next to the truncated or double exon 2 skipped protein. Another preferred but non-limiting example is the skipping of exons 45 through 50. This generates an in-frame Becker-like variant. This Becker-like variant can be generated to cure any mutation localized in exons 45, 46, 47, 48, 49, and/or 50 or combinations thereof. In one aspect, the invention therefore provides a method of the invention further comprising providing the cell with another agent capable of inhibiting an exon inclusion signal in another exon of the pre-mRNA. Of course, it is completely within the scope of the invention to use two or more agents for the induction of exon skipping in pre-mRNA of two or more different genes.
[0025] In another aspect, the invention provides a method for selecting the suitable agents for splice-therapy and their validation as specific exon-skipping agents in pilot experiments. A method is provided for determining whether an agent is capable of specifically inhibiting an exon inclusion signal of an exon, comprising providing a cell having a pre-mRNA containing the exon with the agent, culturing the cell to allow the formation of an mRNA from the pre-mRNA and determining whether the exon is absent the mRNA. In a preferred embodiment, the agent comprises a nucleic acid or a functional equivalent thereof, the nucleic acid comprising complementarity to a part of the exon. Agents capable of inducing specific exon skipping can be identified with a method of the invention. It is possible to include a prescreen for agents by first identifying whether the agent is capable of binding with a relatively high affinity to an exon containing nucleic acid, preferably RNA. To this end, a method for determining whether an agent is capable of specifically inhibiting an exon inclusion signal of an exon is provided, further comprising first determining in vitro the relative binding affinity of the nucleic acid or functional equivalent thereof to an RNA molecule comprising the exon.
[0026] In yet another aspect, an agent is provided that is obtainable by a method of the invention. In a preferred embodiment, the agent comprises a nucleic acid or a functional equivalent thereof. Preferably the agent, when used to induce exon skipping in a cell, is capable of at least in part reducing the amount of aberrant protein in the cell. More preferably, the exon skipping results in an mRNA encoding a protein that is capable of performing a function in the cell. In a particularly preferred embodiment, the pre-mRNA is derived from a dystrophin gene. Preferably, the functional protein comprises a mutant or normal dystrophin protein. Preferably, the mutant dystrophin protein comprises at least the functionality of a dystrophin protein in a Becker patient. In a particularly preferred embodiment, the agent comprises the nucleic acid sequence of hAON#4, hAON#6, hAON#8, hAON#9, hAON#11 and/or one or more of hAON#21-30 or a functional part, derivative and/or analogue of the hAON. A functional part, derivative and/or analogue of the HAON comprises the same exon skipping activity in kind, but not necessarily in amount, in a method of the invention.
[0027] The art describes many ways to deliver agents to cells. Particularly, nucleic acid delivery methods have been widely developed. The artisan is well capable of determining whether a method of delivery is suitable for performing the present invention. In a non-limiting example, the method includes the packaging of an agent of the invention into liposomes, the liposomes being provided to cells comprising a target pre-mRNA. Liposomes are particularly suited for delivery of nucleic acid to cells. Antisense molecules capable of inducing exon skipping can be produced in a cell upon delivery of nucleic acid containing a transcription unit to produce antisense RNA. Non-limiting examples of suitable transcription units are small nuclear RNA (SNRP) or tRNA transcription units. The invention, therefore, further provides a nucleic acid delivery vehicle comprising a nucleic acid or functional equivalent thereof of the invention capable of inhibiting an exon inclusion signal. In one embodiment, the delivery vehicle is capable of expressing the nucleic acid of the invention. Of course, in case, for instance, single-stranded viruses are used as a vehicle, it is entirely within the scope of the invention when such a virus comprises only the antisense sequence of an agent of the invention. In another embodiment of single strand viruses, AONs of the invention are encoded by small nuclear RNA or tRNA transcription units on viral nucleic encapsulated by the virus as vehicle. A preferred single-stranded virus is adeno-associated virus.
[0028] In yet another embodiment, the invention provides the use of a nucleic acid or a nucleic acid delivery vehicle of the invention for the preparation of a medicament. In a preferred embodiment, the medicament is used for the treatment of an inherited disease. More preferably, the medicament is used for the treatment of Duchenne Muscular Dystrophy.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] [0029]FIG. 1. Deletion of exon 45 is one of the most frequent DMD-mutations. Due to this deletion, exon 44 is spliced to exon 46, the translational reading frame is interrupted, and a stop codon is created in exon 46 leading to a dystrophin deficiency. Our aim is to artificially induce the skipping of an additional exon, exon 46, in order to reestablish the reading frame and restore the synthesis of a slightly shorter, but largely functional, dystrophin protein as found in the much milder affected Becker muscular dystrophy patients affected by a deletion of both exons 45 and 46.
[0030] [0030]FIG. 2. Exon 46 contains a purine-rich region that is hypothesized to have a potential role in the regulation of its splicing in the pre-mRNA. A series of overlapping 2′O-methyl phosphorothioate antisense oligoribonucleotides (AONs) was designed directed at this purine-rich region in mouse dystrophin exon 46. The AONs differ both in length and sequence. The chemical modifications render the AONs resistant to endonucleases and RNaseH inside the muscle cells. To determine the transfection efficiency in our in vitro studies, the AONs contained a 5′ fluorescein group which allowed identification of AON-positive cells.
[0031] [0031]FIG. 3. To determine the binding affinity of the different AONs to the target exon 46 RNA, we performed gel mobility shift assays. In this figure, the five mAONs (mAON#4, 6, 8, 9, and 11) with highest affinity for the target RNA are shown. Upon binding of the AONs to the RNA, a complex is formed that exhibits a retarded gel mobility as can be determined by the band shift. The binding of the AONs to the target was sequence-specific. A random mAON, i.e. not specific for exon 46, did not generate a band shift.
[0032] [0032]FIGS. 4A and 4B. The mouse- and human-specific AONs which showed the highest binding affinity in the gel mobility shift assays were transfected into mouse and human myotube cultures.
[0033] [0033]FIG. 4A. RT-PCR analysis showed a truncated product, of which the size corresponded to exon 45 directly spliced to exon 47, in the mouse cell cultures upon transfection with the different mAONs#4, 6, 9, and 11. No exon 46 skipping was detected following transfection with a random AON.
[0034] [0034]FIG. 4B. RT-PCR analysis in the human muscle cell cultures derived from one unaffected individual (C) and two unrelated DMD patients (P1 and P2) revealed truncated products upon transfection with hAON#4 and hAON#8. In the control, this product corresponded to exon 45 spliced to exon 47, while in the patients, the fragment size corresponded to exon 44 spliced to exon 47. No exon 46 skipping was detected in the non-transfected cell cultures or following transfection with a random HAON. Highest exon 46 skipping efficiencies were obtained with hAON#8.
[0035] [0035]FIG. 5. Sequence data from the RT-PCR products obtained from patient DL279.1 (corresponding to P1 in FIG. 4), which confirmed the deletion of exon 45 in this patient (upper panel), and the additional skipping of exon 46 following transfection with hAON#8 (lower panel). The skipping of exon 46 was specific, and exon 44 was exactly spliced to exon 47, which reestablishes the translational reading frame.
[0036] [0036]FIG. 6. Immunohistochemical analysis of the muscle cell culture from patient DL279.1 upon transfection with hAON#8. Cells were subject to two different dystrophin antibodies raised against different regions of the protein, located proximally (ManDys-1, ex. 31-32) and distally (Dys-2, ex. 77-79) from the targeted exon 46. The lower panel shows the absence of a dystrophin protein in the myotubes, whereas the hAON#8-induced skipping of exon 46 clearly restored the synthesis of a dystrophin protein as detected by both antibodies (upper panel).
[0037] [0037]FIG. 7A. RT-PCR analysis of RNA isolated from human control muscle cell cultures treated with hAON#23, #24, #27, #28, or #29. An additional aberrant splicing product was obtained in cells treated with hAON#28 and #29. Sequence analysis revealed the utilization of an in-frame cryptic splice site within exon 51 that is used at a low frequency upon AON treatment. The product generated included a partial exon 51, which also had a restored reading frame, thereby confirming further the therapeutic value.
[0038] [0038]FIG. 7B. A truncated product, with a size corresponding to exon 50 spliced to exon 52, was detected in cells treated with hAON#23 and #28. Sequence analysis of these products confirmed the precise skipping of exon 51.
[0039] [0039]FIG. 8A. Gel mobility shift assays were performed to determine the binding affinity of the different h29AON#'s for the exon 29 target RNA. When compared to non-hybridized RNA (none), h29AON#1, #2, #4, #6, #9, #10, and #11 generated complexes with lower gel mobilities, indicating their binding to the RNA. A random AON derived from dystrophin exon 19 did not generate a complex.
[0040] [0040]FIG. 8B. RT-PCR analysis of RNA isolated from human control muscle cell cultures treated with h29AON#1, #2, #4, #6, #9, #10, or #11 revealed a truncated product of which the size corresponded to exon 28 spliced to exon 30. These results indicate that exon 29 can specifically be skipped using AONs directed to sequences either within (h29AON#1, #2, #4, or #6) or outside (h29AON#9, #10, or #11) the hypothesized ERS in exon 29. An additional aberrant splicing product was observed that resulted from skipping of both exon 28 and exon 29 (confirmed by sequence data not shown). Although this product was also present in non-treated cells, suggesting that this alternative skipping event may occur naturally, it was enhanced by the AON-treatment. AON 19, derived from dystrophin exon 19, did not induce exon 29 skipping.
[0041] [0041]FIG. 8C. The specific skipping of exon 29 was confirmed by sequence data from the truncated RT-PCR fragments. Shown here is the sequence obtained from the exon 29 skipping product in cells treated with h29AON#1.
[0042] [0042]FIG. 9A. RT-PCR analysis of RNA isolated from mouse gastrocnemius muscles two days post-injection of 5, 10, or 20 μg of either mAON#4, #6, or #11. Truncated products, with a size corresponding to exon 45 spliced to exon 47, were detected in all treated muscles. The samples -RT, -RNA, AD-1, and AD-2 were analyzed as negative controls for the RT-PCR reactions.
[0043] [0043]FIG. 9B. Sequence analysis of the truncated products generated by mAON#4 and #6 (and #11, not shown) confirmed the precise skipping of exon 46.
DETAILED DESCRIPTION OF THE INVENTION
EXAMPLES
Example 1
[0044] Since exon 45 is one of the most frequently deleted exons in DMD, we initially aimed at inducing the specific skipping of exon 46 (FIG. 1). This would produce the shorter, largely functional dystrophin found in BMD patients carrying a deletion of exons 45 and 46. The system was initially set up for modulation of dystrophin pre-mRNA splicing of the mouse dystrophin gene. We later aimed for the human dystrophin gene with the intention to restore the translational reading frame and dystrophin synthesis in muscle cells from DMD patients affected by a deletion of exon 45.
[0045] Design of mAONs and hAONs
[0046] A series of mouse- and human-specific AONs (mAONs and hAONs) was designed, directed at an internal part of exon 46 that contains a stretch of purine-rich sequences and is hypothesized to have a putative regulatory role in the splicing process of exon 46 (FIG. 2). For the initial screening of the AONs in the gel mobility shift assays (see below), we used non-modified DNA-oligonucleotides (synthesized by EuroGentec, Belgium). For the actual transfection experiments in muscle cells, we used 2′-O-methyl-phosphorothioate oligoribonucleotides (also synthesized by EuroGentec, Belgium). These modified RNA oligonucleotides are known to be resistant to endonucleases and RNaseH, and to bind to RNA with high affinity. The sequences of those AONs that were eventually effective and applied in muscle cells in vitro are shown below. The corresponding mouse and human-specific AONs are highly homologous but not completely identical.
[0047] The listing below refers to the deoxy-form used for testing, in the finally used 2-O-methyl ribonucleotides all T's should be read as U's.
mAON#2: 5′ GCAATGTTATCTGCTT (SEQ ID NO: 1) mAONH3: 5′ GTTATCTGCTTCTTCC (SEQ ID NO: 2) mAON#4: 5′ CTGCTTCTTCCAGCC (SEQ ID NO: 3) mAON#5: 5′ TCTGCTTCTTCCAGC (SEQ ID NO: 4) mAON#6: 5′ GTTATCTGCTTCTTCCAGCC (SEQ ID NO: 5) mAON#7: 5′ CTTTTAGCTGCTGCTC (SEQ ID NO: 6) mAON#8: 5′ GTTGTTCTTTTAGCTGCTGC (SEQ ID NO: 7) mAON#9: 5′ TTAGCTGCTGCTCAT (SEQ ID NO: 8) mAON#10: 5′ TTTAGCTGCTGCTCATCTCC (SEQ ID NO: 9) mAON#11: 5′ CTGCTGCTCATCTCC (SEQ ID NO: 10) hAON#4: 5′ CTGCTTCCTCCAACC (SEQ ID NO: 11) hAON#6: 5′ GTTATCTGCTTCCTCCAACC (SEQ ID NO: 12) hAON#8: 5′ GCTTTTCTTTTAGTTGCTGC (SEQ ID NO: 13) hAON#9: 5′ TTAGTTGCTGCTCTT (SEQ ID NO: 14) hAON#11: 5′ TTGCTGCTCTTTTCC (SEQ ID NO: 15)
[0048] Gel Mobility Shift Assays
[0049] The efficacy of the AONs is determined by their binding affinity for the target sequence. Notwithstanding recent improvements in computer simulation programs for the prediction of RNA-folding, it is difficult to speculate which of the designed AONs would be capable of binding the target sequence with a relatively high affinity. Therefore, we performed gel mobility shift assays (according to protocols described by Bruice et al., 1997). The exon 46 target RNA fragment was generated by in vitro T7-transcription from a PCR fragment (amplified from either murine or human muscle mRNA using a sense primer that contains the T7 promoter sequence) in the presence of 32P-CTP. The binding affinity of the individual AONs (0.5 pmol) for the target transcript fragments was determined by hybridization at 37° C. for 30 minutes and subsequent polyacrylamide (8%) gel electrophoresis. We performed these assays for the screening of both the mouse and human-specific AONs (FIG. 3). At least 5 different mouse-specific AONs (mAON#4, 6, 8, 9 and 11) and four corresponding human-specific AONs (hAON#4, 6, 8, and 9) generated a mobility shift, demonstrating their binding affinity for the target RNA.
[0050] Transfection Into Muscle Cell Cultures
[0051] The exon 46-specific AONs which showed the highest target binding affinity in gel mobility shift assays were selected for analysis of their efficacy in inducing the skipping in muscle cells in vitro. In all transfection experiments, we included a non-specific AON as a negative control for the specific skipping of exon 46. As mentioned, the system was first set up in mouse muscle cells. We used both proliferating myoblasts and post-mitotic myotube cultures (expressing higher levels of dystrophin) derived from the mouse muscle cell line C2C12. For the subsequent experiments in human-derived muscle cell cultures, we used primary muscle cell cultures isolated from muscle biopsies from one unaffected individual and two unrelated DMD patients carrying a deletion of exon 45. These heterogeneous cultures contained approximately 20-40% myogenic cells. The different AONs (at a concentration of 1 μM) were transfected into the cells using the cationic polymer PEI (MBI Fermentas) at a ratio-equivalent of 3. The AONs transfected in these experiments contained a 5′ fluorescein group which allowed us to determine the transfection efficiencies by counting the number of fluorescent nuclei. Typically, more than 60% of cells showed specific nuclear uptake of the AONs. To facilitate RT-PCR analysis, RNA was isolated 24 hours post-transfection using RNAzol B (CamPro Scientific, The Netherlands).
[0052] RT-PCR and Sequence Analysis
[0053] RNA was reverse transcribed using C. therm. polymerase (Roche) and an exon 48-specific reverse primer. To facilitate the detection of skipping of dystrophin exon 46, the CDNA was amplified by two rounds of PCR, including a nested amplification using primers in exons 44 and 47 (for the human system), or exons 45 and 47 (for the mouse system). In the mouse myoblast and myotube cell cultures, we detected a truncated product of which the size corresponded to exon 45 directly spliced to exon 47 (FIG. 4). Subsequent sequence analysis confirmed the specific skipping of exon 46 from these mouse dystrophin transcripts. The efficiency of exon skipping was different for the individual AONs, with mAON#4 and #11 showing the highest efficiencies. Following these promising results, we focused on inducing a similar modulation of dystrophin splicing in the human-derived muscle cell cultures. Accordingly, we detected a truncated product in the control muscle cells, corresponding to exon 45 spliced to exon 47. Interestingly, in the patient-derived muscle cells, a shorter fragment was detected, which consisted of exon 44 spliced to exon 47. The specific skipping of exon 46 from the human dystrophin transcripts was confirmed by sequence data. This splicing modulation of both the mouse and human dystrophin transcript was neither observed in non-transfected cell cultures nor in cultures transfected with a non-specific AON.
[0054] Imnunohistochemical Analysis
[0055] We intended to induce the skipping of exon 46 in muscle cells from patients carrying an exon 45 deletion in order to restore the translation and synthesis of a dystrophin protein. To detect a dystrophin product upon transfection with hAON#8, the two patient-derived muscle cell cultures were subject to immunocytochemistry using two different dystrophin monoclonal antibodies (Mandys-1 and Dys-2) raised against domains of the dystrophin protein located proximal and distal of the targeted region respectively. Fluorescent analysis revealed restoration of dystrophin synthesis in both patient-derived cell cultures (FIG. 5). Approximately at least 80% of the fibers stained positive for dystrophin in the treated samples.
[0056] Our results show, for the first time, the restoration of dystrophin synthesis from the endogenous DMD gene in muscle cells from DMD patients. This is a proof of principle of the feasibility of targeted modulation of dystrophin pre-mRNA splicing for therapeutic purposes.
[0057] Targeted Skipping of Exon 51
[0058] Simultaneous Skipping of Dystrophin Exons
[0059] The targeted skipping of exon 51. We demonstrated the feasibility of AON-mediated modulation of dystrophin exon 46 splicing, in mouse and human muscle cells in vitro. These findings warranted further studies to evaluate AONs as therapeutic agents for DMD. Since most DMD-causing deletions are clustered in two mutation hot spots, the targeted skipping of one particular exon can restore the reading frame in series of patients with different mutations (see Table 1). Exon 51 is an interesting target exon. The skipping of this exon is therapeutically applicable in patients carrying deletions spanning exon 50, exons 45-50, exons 48-50, exons 49-50, exon 52, and exons 52-63, which includes a total of 15% of patients from our Leiden database.
[0060] We designed a series of ten human-specific AONs (hAON#21-30, see below) directed at different purine-rich regions within dystrophin exon 51. These purine-rich stretches suggested the presence of a putative exon splicing regulatory element that we aimed to block in order to induce the elimination of that exon during the splicing process. All experiments were performed according to protocols as described for the skipping of exon 46 (see above). Gel mobility shift assays were performed to identify those hAONs with high binding affinity for the target RNA. We selected the five hAONs that showed the highest affinity. These hAONs were transfected into human control muscle cell cultures in order to test the feasibility of skipping exon 51 in vitro. RNA was isolated 24 hours post-transfection, and cDNA was generated using an exon 53- or 65-specific reverse primer. PCR-amplification of the targeted region was performed using different primer combinations flanking exon 51. The RT-PCR and sequence analysis revealed that we were able to induce the specific skipping of exon 51 from the human dystrophin transcript. We subsequently transfected two hAONs (#23 and #29) shown to be capable of inducing skipping of the exon into six different muscle cell cultures derived from DMD-patients carrying one of the mutations mentioned above. The skipping of exon 51 in these cultures was confirmed by RT-PCR and sequence analysis (FIG. 7). More importantly, immunohistochemical analysis, using multiple antibodies raised against different parts of the dystrophin protein, showed in all cases that, due to the skipping of exon 51, the synthesis of a dystrophin protein was restored.
[0061] Exon 51-specific hAONs:
hAON#21: 5′ CCACAGGTTGTGTCACCAG (SEQ ID NO: 16) hAON#22: 5′ TTTCCTTAGTAACCACAGGTT (SEQ ID NO: 17) hAON#23: 5′ TGGCATTTCTAGTTTGG (SEQ ID NO: 18) hAON#24: 5′ CCAGAGCAGGTACCTCCAACATC (SEQ ID NO: 19) hAON#25: 5′ GGTAAGTTCTGTCCAAGCCC (SEQ ID NO: 20) hAON#26: 5′ TCACCCTCTGTGATTTTAT (SEQ ID NO: 21) hAON#27: 5′ CCCTCTGTGATTTT (SEQ ID NO: 22) hAON#28: 5′ TCACCCACCATCACCCT (SEQ ID NO: 23) hAON#29: 5′ TGATATCCTCAAGGTCACCC (SEQ ID NO: 24) hAON#30: 5′ CTGCTTGATGATCATCTCGTT (SEQ ID NO: 25)
[0062] Simultaneous Skipping of Multiple Dystrophin Exons
[0063] The skipping of one additional exon, such as exon 46 or exon 51, restores the reading frame for a considerable number of different DMD mutations. The range of mutations for which this strategy is applicable can be enlarged by the simultaneous skipping of more than one exon. For instance, in DMD patients with a deletion of exon 46 to exon 50, only the skipping of both the deletion-flanking exons 45 and 51 enables the reestablishment of the translational reading frame.
[0064] ERS-Independent Exon Skipping
[0065] A mutation in exon 29 leads to the skipping of this exon in two Becker muscular dystrophy patients (Ginjaar at al., 2000, EJHG, vol. 8, p.793-796). We studied the feasibility of directing the skipping of exon 29 through targeting the site of mutation by AONs. The mutation is located in a purine-rich stretch that could be associated with ERS activity. We designed a series of AONs (see below) directed to sequences both within (h29AON#1 to h29AON#6) and outside (h29AON#7 to h29AON#11) the hypothesized ERS. Gel mobility shift assays were performed (as described) to identify those AONs with highest affinity for the target RNA (FIG. 8). Subsequently, h29AON#1, #2, #4, #6, #9, #10, and #11 were transfected into human control myotube cultures using the PEI transfection reagent. RNA was isolated 24 hrs post-transfection, and cDNA was generated using an exon 31-specific reverse primer. PCR-amplification of the targeted region was performed using different primer combinations flanking exon 29. This RT-PCR and subsequent sequence analysis (FIGS. 8B and 8C) revealed that we were able to induce the skipping of exon 29 from the human dystrophin transcript. However, the AONs that facilitated this skipping were directed to sequences both within and outside the hypothesized ERS (h29AON#1, #2, #4, #6, #9, and #11). These results suggest that skipping of exon 29 occurs independent of whether or not exon 29 contains an ERS and that, therefore, the binding of the AONs to exon 29 more likely inactivated an exon inclusion signal rather than an ERS. This proof of ERS-independent exon skipping may extend the overall applicability of this therapy to exons without ERS's.
h29AON#1: 5′ TATCCTCTGAATGTCGCATC (SEQ ID NO: 26) h29AON#2: 5′ GGTTATCCTCTGAATGTCGC (SEQ ID NO: 27) h29AON#3: 5′ TCTGTTAGGGTCTGTGCC (SEQ ID NO: 28) h29AON#4: 5′ CCATCTGTTAGGGTCTGTG (SEQ ID NO: 29) h29AON#5: 5′ GTCTGTGCCAATATGCG (SEQ ID NO: 30) h29AON#6: 5′ TCTGTGCCAATATGCGAATC (SEQ ID NO: 31) h29AON#7: 5′ TGTCTCAAGTTCCTC (SEQ ID NO: 32) h29AON#8: 5′ GAATTAAATGTCTCAAGTTC (SEQ ID NO: 33) h29AON#9: 5′ TTAAATGTCTCAAGTTCC (SEQ ID NO: 34) h29AON#10: 5′ GTAGTTCCCTCCAACG (SEQ ID NO: 35) h29AON#11: 5′ CATGTAGTTCCCTCC (SEQ ID NO: 36)
[0066] AON-Induced Exon 46 Skipping In Vivo in Murine Muscle Tissue.
[0067] Following the promising results in cultured muscle cells, we tested the different mouse dystrophin exon 46-specific AONs in vivo by injecting them, linked to polyethylenimine (PEI), into the gastrocnemius muscles of control mice. With mAON#4, #6, and #11, previously shown to be effective in mouse muscle cells in vitro, we were able to induce the skipping of exon 46 in muscle tissue in vivo as determined by both RT-PCR and sequence analysis (FIG. 9). The in vivo exon 46 skipping was dose-dependent with highest efficiencies (up to 10%) following injection of 20 μg per muscle per day for two subsequent days.
REFERENCES
[0068] Achsel et al., 1996, J. Biochem. 120, pp.53-60.
[0069] Bruice T. W. and Lima, W. F., 1997, Biochemistry 36(16): pp. 5004-5019.
[0070] Brunak at al., 1991, J. Mol. Biol. 220, pp. 49-65.
[0071] Dunckley, M. G. et al., 1998, Human molecular genetics 7, pp. 1083-1090.
[0072] Ginjaar et al., 2000, EJHG, vol. 8, pp. 793-796.
[0073] Mann et al., 2001, PNAS vol. 98, pp. 42-47.
[0074] Tanaka et al., 1994 Mol. Cell. Biol. 14, pp. 1347-1354.
[0075] Wilton, S. D., et al., 1999, Neuromuscular disorders 9, pp. 330-338.
[0076] Details and background on Duchenne Muscular Dystrophy and related diseases can be found on website http://www.dmd.nl
1
36
1
16
DNA
Mouse
1
gcaatgttat ctgctt 16
2
16
DNA
Mouse
2
gttatctgct tcttcc 16
3
14
DNA
Mouse
3
tgcttcttcc agcc 14
4
15
DNA
Mouse
4
tctgcttctt ccagc 15
5
20
DNA
Mouse
5
gttatctgct tcttccagcc 20
6
16
DNA
Mouse
6
cttttagctg ctgctc 16
7
20
DNA
Mouse
7
gttgttcttt tagctgctgc 20
8
15
DNA
Mouse
8
ttagctgctg ctcat 15
9
20
DNA
Mouse
9
tttagctgct gctcatctcc 20
10
15
DNA
Mouse
10
ctgctgctca tctcc 15
11
15
DNA
Human
11
ctgcttcctc caacc 15
12
20
DNA
Human
12
gttatctgct tcctccaacc 20
13
20
DNA
Human
13
gcttttcttt tagttgctgc 20
14
15
DNA
Human
14
ttagttgctg ctctt 15
15
15
DNA
Human
15
ttgctgctct tttcc 15
16
19
DNA
Human
16
ccacaggttg tgtcaccag 19
17
21
DNA
Human
17
tttccttagt aaccacaggt t 21
18
17
DNA
Human
18
tggcatttct agtttgg 17
19
23
DNA
Human
19
ccagagcagg tacctccaac atc 23
20
20
DNA
Human
20
ggtaagttct gtccaagccc 20
21
19
DNA
Human
21
tcaccctctg tgattttat 19
22
14
DNA
Human
22
ccctctgtga tttt 14
23
17
DNA
Human
23
tcacccacca tcaccct 17
24
20
DNA
Human
24
tgatatcctc aaggtcaccc 20
25
21
DNA
Human
25
ctgcttgatg atcatctcgt t 21
26
20
DNA
Human
26
tatcctctga atgtcgcatc 20
27
20
DNA
Human
27
ggttatcctc tgaatgtcgc 20
28
18
DNA
Human
28
tctgttaggg tctgtgcc 18
29
19
DNA
Human
29
ccatctgtta gggtctgtg 19
30
17
DNA
Human
30
gtctgtgcca atatgcg 17
31
20
DNA
Human
31
tctgtgccaa tatgcgaatc 20
32
15
DNA
Human
32
tgtctcaagt tcctc 15
33
20
DNA
Human
33
gaattaaatg tctcaagttc 20
34
18
DNA
Human
34
ttaaatgtct caagttcc 18
35
16
DNA
Human
35
gtagttccct ccaacg 16
36
15
DNA
Human
36
catgtagttc cctcc 15 | The present invention provides a method for at least in part decreasing the production of an aberrant protein in a cell, the cell comprising pre-mRNA comprising exons coding for the protein, by inducing so-called exon skipping in the cell. Exon-skipping results in mature MRNA that does not contain the skipped exon, which leads to an altered product of the exon codes for amino acids. Exon skipping is performed by providing a cell with an agent capable of specifically inhibiting an exon inclusion signal, for instance, an exon recognition sequence, of the exon. The exon inclusion signal can be interfered with by a nucleic acid comprising complementarity to a part of the exon. The nucleic acid, which is also herewith provided, can be used for the preparation of a medicament, for instance, for the treatment of an inherited disease. | 2 |
BACKGROUND
[0001] This invention relates to detection of individuals at risk for pathological conditions based on the presence of single nucleotide polymorphisms (SNPs) at positions 2239 and 2657 on the human endothelin-1 (EDN-1) promoter.
[0002] During the course of evolution, spontaneous mutations appear in the genomes of organisms. It has been estimated that variations in genomic DNA sequences are created continuously at a rate of about 100 new single base changes per individual (Kondrashow, J. Theor. Biol., 175:583-594, 1995; Crow, Exp. Clin. Immunogenet., 12:121-128, 1995). These changes, in the progenitor nucleotide sequences, may confer an evolutionary advantage, in which case the frequency of the mutation will likely increase, an evolutionary disadvantage in which case the frequency of the mutation is likely to decrease, or the mutation will be neutral. In certain cases, the mutation may be lethal in which case the mutation is not passed on to the next generation and skis quickly eliminated from the population. In many cases, an equilibrium is established between the progenitor and mutant sequences so that both are present in the population. The presence of both forms of the sequence results in genetic variation or polymorphism. Over time, a significant number of mutations can accumulate within a population such that considerable polymorphism can exist between individuals within the population.
[0003] Numerous types of polymorphisms are known to exist. Polymorphisms can be created when DNA sequences are either inserted or deleted from the genome, for example, by viral insertion. Another source of sequence variation can be caused by the presence of repeated sequences in the genome variously termed short tandem repeats (STR), variable number tandem repeats (VNTR), short sequence repeats (SSR) or microsatellites. These repeats can be dinucleotide, trinucleotide, tetranucleotide or pentanucleotide repeats. Polymorphism results from variation in the number of repeated sequences found at a particular locus.
[0004] By far the most common source of variation in the genome is the single nucleotide polymorphism or SNP. SNPs account for approximately 90% of human DNA polymorphism (Collins et al., Genome Res., 8:1229-1231, 1998). SNPs are single base pair positions in genomic DNA at which different sequence alternatives (alleles) exist in a population. In addition, the least frequent allele must occur at a frequency of 1% or greater. Several definitions of SNPs exist in the literature (Brooks, Gene, 234:177-186, 1999). As used herein, the term “single nucleotide polymorphism” or “SNP” includes all single base variants and so includes nucleotide insertions and deletions in addition to single nucleotide substitutions (e.g. A→G). Nucleotide substitutions are of two types. A transition is the replacement of one purine by another purine or one pyrimidine by another pyrimidine. A transversion is the replacement of a purine for a pyrimidine or vice versa.
[0005] The typical frequency at which SNPs are observed is about 1 per 1000 base pairs (Li and Sadler, Genetics, 129:513-523, 1991; Wang et al., Science, 280:1077-1082, 1998; Harding et al., Am. J. Human Genet., 60:772-789, 1997; Taillon-Miller et al., Genome Res., 8:748-754, 1998). The frequency of SNPs varies with the type and location of the change. In base substitutions, two-thirds of the substitutions involve the C⇄T (G⇄A) type. This variation in frequency is thought to be related to 5-methylcytosine deamination reactions that occur frequently, particularly at CpG dinucleotides. In regard to location, SNPs occur at a much higher frequency in non-coding regions than they do in coding regions.
[0006] SNPs can be associated with disease conditions in humans or animals. The association can be direct, as in the case of genetic diseases where the alteration in the genetic code caused by the SNP directly results in the disease condition. Examples of diseases in which single nucleotide polymorphisms result in disease conditions are sickle cell anemia and cystic fibrosis. The association can also be indirect, where the SNP does not directly cause the disease but alters the physiological environment such that there is an increased likelihood that the patient will develop the disease. SNPs can also be associated with disease conditions, but play no direct or indirect role in causing the disease. In this case, the SNP is located close to the defective gene, usually within 5 centimorgans, such that there is a strong association between the presence of the SNP and the disease state. Because of the high frequency of SNPs within the genome, there is a greater probability that a SNP will be linked to a genetic locus of interest than other types of genetic markers.
[0007] Disease associated SNPs can occur in coding and non-coding regions of the genome. When located in a coding region, the presence of the SNP can result in the production of a protein that is non-functional or has decreased function. More frequently, SNPs occur in non-coding regions. If the SNP occurs in a regulatory region, it may affect expression of the protein. For example, the presence of a SNP in a promoter region, may cause decreased expression of a protein. If the protein is involved in protecting the body against development of a pathological condition, this decreased expression can make the individual more susceptible to the condition.
[0008] Numerous methods exist for the detection of SNPs within a nucleotide sequence. A review of many of these methods can be found in Landegren et al., Genome Res., 8:769-776, 1998. SNPs can be detected by restriction fragment length polymorphism (RFLP) (U.S. Pat. Nos. 5,324,631; 5,645,995). RFLP analysis of the SNPs, however, is limited to cases where the SNP either creates or destroys a restriction enzyme cleavage site. SNPs can also be detected by direct sequencing of the nucleotide sequence of interest. Numerous assays based on hybridization have also been developed to detect SNPs. In addition, mismatch distinction by polymerases and ligases has also been used to detect SNPs.
[0009] There is growing recognition that SNPs can provide a powerful tool for the detection of individuals whose genetic make-up alters their susceptibility to certain diseases. There are four primary reasons why SNPs are especially suited for the identification of genotypes which predispose an individual to develop a disease condition. First, SNPs are by far the most prevalent type of polymorphism present in the genome and so are likely to be present in or near any locus of interest. Second, SNPs located in genes can be expected to directly affect protein structure or expression levels and so may serve not only as markers but as candidates for gene therapy treatments to cure or prevent a disease. Third, SNPs show greater genetic stability than repeated sequences and so are less likely to undergo changes which would complicate diagnosis. Fourth, the increasing efficiency of methods of detection of SNPs make them especially suitable for high throughput typing systems necessary to screen large populations.
SUMMARY
[0010] The present inventor has discovered novel single nucleotide polymorphisms (SNPs) associated with the development of various diseases, including hypertension (HTN), end stage renal disease due to hypertension (ESRD due to HTN), non-insulin dependent diabetes mellitus (NIDDM), end stage renal disease due to non-insulin dependent diabetes mellitus (ESRD due to NIDDM), lung cancer, breast cancer, prostate cancer, colon cancer, atherosclerotic peripheral vascular disease due to hypertension (ASPVD due to HTN), cerebrovascular accident due to hypertension (CVA due to HTN), cataracts due to hypertension (cataracts due to HTN), cardiomyopathy with hypertension (HTN CM), myocardial infarction due to hypertension (MI due to HTN), atherosclerotic peripheral vascular disease due to non-insulin dependent diabetes mellitus (ASPVD due to NIDDM), cerebrovascular accident due to non-insulin dependent diabetes mellitus (CVA due to NIDDM), ischemic cardiomyopathy (Ischemic CM), ischemic cardiomyopathy with non-insulin dependent diabetes mellitus (Ischemic CM with NIDDM), myocardial infarction due to non-insulin dependent diabetes mellitus (MI due to NIDDM), atrial fibrillation without valvular disease (afib without valvular disease), alcohol abuse, anxiety, asthma, chronic obstructive pulmonary disease (COPD), cholecystectomy, degenerative joint disease (DJD), end stage renal disease and frequent de-clots (ESRD and frequent de-clots), end stage renal disease due to focal segmental glomerular sclerosis (ESRD due to FSGS), end stage renal disease due to insulin dependent diabetes mellitus (ESRD due to IDDM), or seizure disorder. As such, this polymorphism provides a method for diagnosing a genetic predisposition for the development of these diseases in individuals. Information obtained from the detection of SNPs associated with the development of these diseases is of great value in their treatment and prevention.
[0011] Accordingly, one aspect of the present invention provides a method for diagnosing a genetic predisposition for HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder in a subject, comprising obtaining a sample containing at least one polynucleotide from the subject, and analyzing the polynucleotide to detect a genetic polymorphism wherein the presence or absence of said genetic polymorphism is associated with an altered susceptibility to developing HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder. In one embodiment, the polymorphism is located in the EDN-1 gene.
[0012] Another aspect of the present invention provides an isolated nucleic acid sequence comprising at least 10 contiguous nucleotides from SEQ ID NO: 1, or their complements, wherein the sequence contains at least one polymorphic site associated with a disease and in particular HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder.
[0013] Yet another aspect of the invention is a kit for the detection of a polymorphism comprising, at a minimum, at least one polynucleotide of at least 10 contiguous nucleotides of SEQ ID NO: 1, or their complements, wherein the polynucleotide contains at least one polymorphic site associated with HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder.
[0014] Yet another aspect of the invention provides a method for treating HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast canter, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder comprising, obtaining a sample of biological material containing at least one polynucleotide from the subject; analyzing the polynucleotide to detect the presence of at least one polymorphism associated with HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder; and treating the subject in such a way as to counteract the effect of any such polymorphism detected.
[0015] Still another aspect of the invention provides a method for the prophylactic treatment of a subject with a genetic predisposition to HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder comprising, obtaining a sample of biological material containing at least one polynucleotide from the subject; analyzing the polynucleotide to detect the presence of at least one polymorphism associated with HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder, and treating the subject.
[0016] Further scope of the applicability of the present invention will become apparent from the detailed description and drawings provided below. It should be understood, however, that the following detailed description and examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:
[0018] [0018]FIG. 1 shows SEQ ID NO: 1, the nucleotide sequence of the EDN-1 promoter region as contained in GenBank Accession Number J05008. 1. Position of the single nucleotide polymorphisms (SNPs) are here given according to the numbering scheme in GenBank Accession Number J05008.1. Thus, all nucleotides will be positively numbered, rather than bear negative numbers reflecting their position upstream from the RNA polymerase II binding site (a TATA box in about half of eukaryotic genes), the transcription initiation site (a variable number of nucleotides downstream of, i.e. 3′ to, the TATA box), the translation start site, or the first codon of the encoded protein (the “A” of the “ATO” codon for methionine, the first amino acid of every protein). Since not all genes are fully annotated, and not all promoter sequences contain elements far downstream such as the “ATG” encoding the first methionine in the translated protein, the numbering system used in this patent application is less troublesome.
[0019] The various numbering systems can be easily interconverted, if desired. According to the annotation of Accession Number, the TATA box is located at position 3577. The first exon begins at position 3608. The position of the ATG codon for the first amino acid (methionine) of the protein is at position 3876.
[0020] The first SNP mentioned below is located at position 2239 of Accession Number J05008.1. According to the annotation of Accession Number J05008.1, the transcription start site is position 3608. Therefore, the T2239→G SNP would be −1369 relative to the transcription start position. Further, according to the annotation of Accession Number J05008.1, the position of the “A” of the ATG codon for the first amino acid (methionine) of the protein, i.e.—the translation start site, is at position 3876. The T2239→G SNP corresponds to −1637 with reference to the translation initiation site (the “A” of the first encoded “ATG”).
[0021] The second SNP mentioned below (A2657→C) is located at position 2657 according to the numbering scheme of GenBank Accession Number Jp05008.1. Again, according to the annotation of Accession Number J05008.1, the transcription start site is position 3608. Therefore, the A2657→C SNP would be −951 relative to the transcription start position. Further, according to the annotation of Accession Number J05008.1, the position of the “A” of the ATG codon for the first amino acid (methionine) of the protein, i.e.—the translation start site, is at position 3876. The A2657→C SNP corresponds to −1219 with reference to the translation initiation site (the “A” of the first encoded “ATG”).
DEFINITIONS
[0022] nt=nucleotide
[0023] bp=base pair
[0024] kb=kilobase; 1000 base pairs
[0025] ASPVD=atherosclerotic peripheral vascular disease
[0026] COPD=chronic obstructive pulmonary disease
[0027] CVA=cerebrovascular accident
[0028] DJD=degenerative joint disease, also know as osteoarthritis
[0029] DOL=dye-labeled oligonucleotide ligation assay
[0030] ESRD=end-stage renal disease
[0031] FSGS=focal segmental glomerular sclerosis
[0032] HTN=hypertension
[0033] MASDA=multiplexed allele-specific diagnostic assay
[0034] MADGE=microtiter array diagonal gel electrophoresis
[0035] MI=myocardial infarction
[0036] NIDDM=noninsulin-dependent diabetes mellitus
[0037] OLA=oligonucleotide ligation assay
[0038] PCR=polymerase chain reaction
[0039] RFLP=restriction fragment length polymorphism
[0040] SNP=single nucleotide polymorphism
[0041] “Polynucleotide” and “oligonucleotide” are used interchangeably and mean a linear polymer of at least 2 nucleotides joined together by phosphodiester bonds and may consist of either ribonucleotides or deoxyribonucleotides.
[0042] “Sequence” means the linear order in which monomers occur in a polymer, for example, the order of albino acids in a polypeptide or the order of nucleotides in a polynucleotide.
[0043] “Polymorphism” refers to a set of genetic variants at a particular genetic locus among individuals in a population.
[0044] “Promoter” means a regulatory sequence of DNA that is involved in the binding of RNA polymerase to initiate transcription of a gene. A “gene” is a segment of DNA involved in producing a peptide, polypeptide, or protein, including the coding region, non-coding regions preceding (“leader”) and following (“trailer”) coding region, as well as intervening non-coding sequences (“introns” between individual coding segments (“exons”). A promoter is herein considered as a part of the corresponding gene. Coding refers to the representation of amino acids, start and stop signals in a three base “triplet” code. Promoters are often upstream (“5′ to”) the transcription initiation site of the gene.
[0045] “Gene therapy” means the introduction of a functional gene or genes from some source by any suitable method into a living cell to correct for a genetic defect.
[0046] “Reference allele” or “reference type” means the allele designated in the Gen Bank sequence listing for a given gene, in this case Gen Bank Accession Number J05008.1 for the endothelin-1 gene.
[0047] “Genetic variant” or “variant” means a specific genetic variant which is present at a particular genetic locus in at least one individual in a population and that differs from the reference type.
[0048] As used herein the terms “patient” and “subject” are not limited to human beings, but are intended to include all vertebrate animals in addition to human beings.
[0049] As used herein the terms “genetic predisposition”, “genetic susceptibility” and “susceptibility” all refer to the likelihood that an individual subject will develop a particular disease, condition or disorder. For example, a subject with an increased susceptibility or predisposition will be more likely than average to develop a disease, while a subject with a decreased predisposition will be less likely than average to develop the disease. A genetic variant is associated with an altered susceptibility or predisposition if the allele frequency of the genetic variant in a population or subpopulation with a disease, condition or disorder varies from its allele frequency in the population without the disease, condition or disorder (control population) or a control sequence (reference type) by at least 1%, preferably by at least 2%, more preferably by at least 4% and more preferably still by at least 8%. Altematively, an odds ratio of 1.5 was chosen as the threshold of significance based on the recommendation of Austin et al. in Epidemiol. Rev., 16:65-76, 1994. “[E]pidemiology in general and case-control studies in particular are not well suited for detecting weak associations (odds ratios <1.5).” Id. at 66.
[0050] As used herein “isolated nucleic acid” means a species of the invention that is the predominate species present (i.e., on a molar basis it is more abundant than any other individual species in the composition). Preferably, an isolated nucleic acid comprises at least about 50, 80 or 90 percent (on a molar basis) of all macromolecular species present. Most preferably, the object species is purified to essential homogeneity (contaminant species cannot be detected in the composition by conventional detection methods).
[0051] As used herein, “allele frequency” means the frequency that a given allele appears in a population.
DETAILED DESCRIPTION
[0052] All publications, patents, patent applications and other references cited in this application are herein incorporated by reference in their entirety as if each individual publication, patent, patent application or other reference were specifically and individually indicated to be incorporated by reference.
[0053] Novel Polymorphisms
[0054] The present application provides single nucleotide polymorphisms (SNPs) in a gene associated with HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder. The first polymorphism is a T to G transversion at position 2239 and the second polymorphism is an A to C substitution at position 2657, both of the EDN-1 promoter.
[0055] Preparation of Samples
[0056] The presence of genetic variants in the above genes or their control regions, or in any other genes that may affect susceptibility to disease is determined by screening nucleic acid sequences from a population of individuals for such variants. The population is preferably comprised of some individuals with the disease of interest, so that any genetic variants that are found can be correlated with disease. The population is also preferably comprised of some individuals that have known risk for the disease. The population should preferably be large enough to have a reasonable chance of finding individuals with the sought-after genetic variant. As the size of the population increases, the ability to find significant correlations between a particular genetic variant and susceptibility to disease also increases.
[0057] The nucleic acid sequence can be DNA or RNA. For the assay of genomic DNA, virtually any biological sample containing genomic DNA (e.g., not pure red blood cells) can be used. For example, and without limitation, genomic DNA can be conveniently obtained from whole blood, semen, saliva, tears, urine, fecal material, sweat, buccal cells, skin or hair. For assays using cDNA or mRNA, the target nucleic acid must be obtained from cells or tissues that express the target sequence. One preferred source and quantity of DNA is 10 to 30 ml of anticoagulated whole blood, since enough DNA can be extracted from leukocytes in such a sample to perform many repetitions of the analysis contemplated herein.
[0058] Many of the methods described herein require the amplification of DNA from target samples. This can be accomplished by any method known in the art but preferably is by the polymerase chain reaction (PCR). Optimization of conditions for conducting PCR must be determined for each reaction and can be accomplished without undue experimentation by one of ordinary skill in the art. In general, methods for conducting PCR can be found in U.S. Pat. Nos 4,965,188, 4,800,159, 4,683,202, and 4,683,195; Ausbel et al., eds., Short Protocols in Molecular Biology, 3 rd ed., Wiley, 1995; and Innis et al., eds., PCR Protocols, Academic Press, 1990.
[0059] Other amplification methods include the ligase chain reaction (LCR) (see, Wu and Wallace, Genomics, 4:560-569, 1989; Landegren et al., Science, 241:1077-1080, 1988), transcription amplification (Kwoh et al., Proc. Natl. Acad. Sci. USA, 86:1173-1177, 1989), self-sustained sequence replication (Guatelli et al., Proc. Natl. Acad. Sci. USA, 87:1874-1878, 1990), and nucleic acid based sequence amplification (NASBA). The latter two amplification methods involve isothermal reactions based on isothermal transcription, which produces both single stranded RNA (ssRNA) and double stranded DNA (dsDNA) as the amplification products in a ratio of about 30 or 100 to 1, respectively.
[0060] Detection of Polymorphisms
[0061] Detection of Unknown Polymorphisms
[0062] Two types of detection are contemplated within the present invention. The first type involves detection of unknown SNPs by comparing nucleotide target sequences from individuals in order to detect sites of polymorphism. If the most common sequence of the target nucleotide sequence is not known, it can be determined by analyzing individual humans, animals or plants with the greatest diversity possible. Additionally the frequency of sequences found in subpopulations characterized by such factors as geography or gender can be determined.
[0063] The presence of genetic variants and in particular SNPs is determined by screening the DNA and/or RNA of a population of individuals for such variants. If it is desired to detect variants associated with a particular disease or pathology, the population is preferably comprised of some individuals with the disease or pathology, so that any genetic variants that are found can be correlated with the disease of interest. It is also preferable that the population be composed of individuals with known risk factors for the disease. The populations should preferably be large enough to have a reasonable chance to find correlations between a particular genetic variant and susceptibility to the disease of interest. In addition, the allele frequency of the genetic variant in a population or subpopulation with the disease or pathology should vary from its allele frequency in the population without the disease or pathology (control population) or the control sequence (reference type) by at least 1%, preferably by at least 2%, more preferably by at least 4% and more preferably still by at least 8%.
[0064] Determination of unknown genetic variants, and in particular SNPs, within a particular nucleotide sequence among a population may be determined by any method known in the art, for example and without limitation, direct sequencing, restriction length fragment polymorphism (RFLP), single-strand conformational analysis (SSCA), denaturing gradient gel electrophoresis (DGGE), heteroduplex analysis (HET), chemical cleavage analysis (CCM) and ribonuclease cleavage.
[0065] Methods for direct sequencing of nucleotide sequences are well known to those skilled in the art and can be found for example in Ausubel et al., eds., Short Protocols in Molecular Biology, 3 rd ed., Wiley, 1995 and Sambrook et al., Molecular Cloning, 2 nd ed., Chap. 13, Cold Spring Harbor Laboratory Press, 1989. Sequencing can be carried out by any suitable method, for example, dideoxy sequencing (Sanger et al., Proc. Natl. Acad. Sci. USA, 74:5463-5467, 1977), chemical sequencing (Maxam and Gilbert, Proc. Natl. Acad. Sci. USA, 74:560-564, 1977) or variations thereof. Direct sequencing has the advantage of determining variation in any base pair of a particular sequence.
[0066] RFLP analysis (see, e.g. U.S. Pat. Nos. 5,324,631 and 5,645,995) is useful for detecting the presence of genetic variants at a locus in a population when the variants differ in the size of a probed restriction fragment within the locus, such that the difference between the variants can be visualized by electrophoresis. Such differences will occur when a variant creates or eliminates a restriction site within the probed fragment. RFLP analysis is also useful for detecting a large insertion or deletion within the probed fragment. Thus, RFLP analysis is useful for detecting, e.g., an Alu sequence insertion or deletion in a probed DNA segment.
[0067] Single-strand conformational polymorphisms (SSCPs) can be detected in <220 bp PCR amplicons with high sensitivity (Orita et al, Proc. Natl. Acad. Sci. USA, 86:2766-2770, 1989; Warren et al., In: Current Protocols in Human Genetics, Dracopoli et al., eds, Wiley, 1994, 7.4.1-7.4.6.). Double strands are first heat-denatured. The single strands are then subjected to polyacrylamide gel electrophoresis under non-denaturing conditions at constant temperature (i.e., low voltage and long run times) at two different temperatures, typically 4-10° C. and 23° C. (room temperature). At low temperatures (4-10° C.), the secondary structure of short single strands (degree of intrachain hairpin formation) is sensitive to even single nucleotide changes, and can be detected as a large change in electrophoretic mobility. The method is empirical, but highly reproducible, suggesting the existence of a very limited number of folding pathways for short DNA strands at the critical temperature. Polymorphisms appear as new banding patterns when the gel is stained.
[0068] Denaturing gradient gel electrophoresis (DGGE) can detect single base mutations based on differences in migration between homo- and heteroduplexes (Myers et al., Nature, 313:495-498, 1985). The DNA sample to be tested is hybridized to a labeled reference type probe. The duplexes formed are then subjected to electrophoresis through a polyacrylamide gel that contains a gradient of DNA denaturant parallel to the direction of electrophoresis. Heteroduplexes formed due to single base variations are detected on the basis of differences in migration between the heteroduplexes and the homoduplexes formed.
[0069] In heteroduplex analysis (HET) (Keen et al., Trends Genet. 7:5, 1991), genomic DNA is amplified by the polymerase chain reaction followed by an additional denaturing step which increases the chance of heteroduplex formation in heterozygous individuals. The PCR products are then separated on Hydrolink gels where the presence of the heteroduplex is observed as an additional band.
[0070] Chemical cleavage analysis (CCM) is based on the chemical reactivity of thymine (T) when mismatched with cytosine, guanine or thymine and the chemical reactivity of cytosine (C) when mismatched with thymine, adenine or cytosine (Cotton et al., Proc. Natl. Acad. Sci. USA, 85:4397-4401, 1988). Duplex DNA formed by hybridization of a reference type probe with the DNA to be examined, is treated with osmium tetroxide for T and C mismatches and hydroxylamine for C mismatches. T and C mismatched bases that have reacted with the hydroxylamine or osmium tetroxide are then cleaved with piperidine. The cleavage products are then analyzed by gel electrophoresis.
[0071] Ribonuclease cleavage involves enzymatic cleavage of RNA at a single base mismatch in an RNA:DNA hybrid (Myers et al., Science 230:1242-1246, 1985). A 32 P labeled RNA probe complementary to the reference type DNA is annealed to the test DNA and then treated with ribonuclease A. If a mismatch occurs, ribonuclease A will cleave the RNA probe and the location of the mismatch can then be determined by size analysis of the cleavage products following gel electrophoresis.
[0072] Detection of Known Polymorphisms
[0073] The second type of polymorphism detection involves determining which form of a known polymorphism is present in individuals for diagnostic or epidemiological purposes. In addition to the already discussed methods for detection of polymorphisms, several methods have been developed to detect known SNPs. Many of these assays have been reviewed by Landegren et al., Genome Res., 8:769-776, 1998, and will only be briefly reviewed here.
[0074] One type of assay has been termed an array hybridization assay, an example of which is the multiplexed allele-specific diagnostic assay (MASDA) (U.S. Pat. No. 5,834,181; Shuber et al., Hum. Molec. Genet., 6:337-347, 1997). In MASDA, samples from multiplex PCR are immobilized on a solid support. A single hybridization is conducted with a pool of labeled allele specific oligonucleotides (ASO). Any ASOs that hybridize to the samples are removed from the pool of ASOs. The support is then washed to remove unhybridized ASOs remaining in the pool. Labeled ASOs remaining on the support are detected and eluted from the support. The eluted ASOs are then sequenced to determine the mutation present.
[0075] Two assays depend on hybridization-based allele-discrimination during PCR. The TaqMan assay (U.S. Pat. No. 5,962,233; Livak et al., Nature Genet., 9:341-342, 1995) uses allele specific (ASO) probes with a donor dye on one end and an acceptor dye on the other end, such that the dye pair interact via fluorescence resonance energy transfer (FRET). A target sequence is amplified by PCR modified to include the addition of the labeled ASO probe. The PCR conditions are adjusted so that a single nucleotide difference will effect binding of the probe. Due to the 5′ nuclease activity of the Taq polymerase enzyme, a perfectly complementary probe is cleaved during the PCR while a probe with a single mismatched base is not cleaved. Cleavage of the probe dissociates the donor dye from the quenching acceptor dye, greatly increasing the donor fluorescence.
[0076] An alternative to the TaqMan assay is the molecular beacons assay (U.S. Pat. No. 5,925,517; Tyagi et al., Nature Biotech., 16:49-53, 1998). In the molecular beacons method for real time detection of the presence of target sequences or can be used after amplification.
[0077] High throughput screening for SNPs that affect restriction sites can be achieved by Microtiter Array Diagonal Gel Electrophoresis (MADGE) (Day and Humphries, Anal. Biochem., 222:389-395, 1994). In this assay restriction fragment digested PCR products are loaded onto stackable horizontal gels with the wells arrayed in a nicrotiter format. During electrophoresis, the electric field is applied at an angle relative to the columns and rows of the wells allowing products from a large number of reactions to be resolved.
[0078] Additional assays for SNPs depend on mismatch distinction by polymerases and ligases. The polymerization step in PCR places high stringency requirements on correct base pairing of the 3′ end of the hybridizing primers. This has allowed the use of PCR for the rapid detection of single base changes in DNA by using specifically designed oligonucleotides in a method variously called PCR amplification of specific alleles (PASA) (Sommer et al., Mayo Clin. Proc., 64:1361-1372, 1989; Sarker et al., Anal. Biochem., 1990), allele-specific amplification (ASA), allele-specific ICR, and amplification refractory mutation system (ARMS) (Newton et al., Nuc. Acids Res., 1989; Nichols et al., Genomics, 1989; Wu et al., Proc. Natl. Acad. Sci. USA, 1989). In these methods, an oligonucleotide primer is designed that perfectly matches one allele but mismatches the other allele at or near the 3′ end. This results in the preferential amplification of one allele over the other. By using three primers that produce two differently sized products, it can be determined whether an individual is homozygous or heterozygous for the mutation (Dutton and Sommer, BioTechlniques, 11:700-702, 1991). In another method, termed bi-PASA, four primers are used; two outer primers that bind at different distances from the site of the SNP and two allele specific inner primers (Liu et al., Genome Res., 7:389-398, 1997). Each of the inner primers has a non-complementary 5′ end and form a mismatch near the 3′ end if the proper allele is not present. Using this system, zygosity is determined based on the size and number of PCR products produced.
[0079] The joining by DNA ligases of two oligonucleotides hybridized to a target DNA sequence is quite sensitive to mismatches close to the ligation site, especially at the 3′ end. This sensitivity has been utilized in the oligonucleotide ligation assay (Landegren et al., Science, 241:1077-1080, 1988) and the ligase chain reaction (LCR; Barany, Proc. Natl. Acad. Sci. USA, 88:189-193, 1991). In OLA, the sequence surrounding the SNP is first amplified by PCR, whereas in LCR, genomic DNA can be used as a template.
[0080] In one method for mass screening for SNPs based on the OLA, amplified DNA templates are analyzed for their ability to serve as templates for ligation reactions between labeled oligonucleotide probes (Samotiaki et al., Genomics, 20:238-242, 1994). In this assay, two allele-specific probes labeled with either of two lanthanide labels (europium or terbium) compete for ligation to a third biotin labeled phosphorylated oligonucleotide and the signals from the allele specific oligonucleotides are compared by time-resolved fluorescence. After ligation, the oligonucleotides are collected on an avidin-coated 96-pin capture manifold. The collected oligonucleotides are then transferred to microtiter wells in which the europium and terbium ions are released. The fluorescence from the europium ions is determined for each well, followed by measurement of the terbium fluorescence.
[0081] In alternative gel-based OLA assays, numerous SNPs can be detected simultaneously using multiplex PCR and multiplex ligation (U.S. Pat. No. 5,830,711; Day et al., Genomics, 29:152-162, 1995; Grossman et al., Nuc. Acids Res., 22:4527-4534, 1994). In these assays, allele specific oligonucleotides with different markers, for example, fluorescent dyes, are used. The ligation products are then analyzed together by electrophoresis on an automatic DNA sequencer distinguishing markers by size and alleles by fluorescence. In the assay by Grossman et al., 1994, mobility is further modified by the presence of a non-nucleotide mobility modifier on one of the oligonucleotides.
[0082] A further modification of the ligation assay has been termed the dye-labeled oligonucleotide ligation (DOL) assay (U.S. Pat. No. 5,945,283; Chen et al., Genome Res., 8:549-556, 1998). DOL combines PCR and the oligonucleotide ligation reaction in a two-stage thermal cycling sequence with fluorescence resonance energy transfer (FRET) detection. In the assay, labeled ligation oligonucleotides are designed to have annealing temperatures lower than those of the amplification primers. After amplification, the temperature is lowered to a temperature where the ligation oligonucleotides can anneal and be ligated together. This assay requires the use of a thermostable ligase and a thermostable DNA polymerase without 5′ nuclease activity. Because FRET occurs only when the donor and acceptor dyes are in close proximity, ligation is inferred by the change in fluorescence.
[0083] In another method for the detection of SNPs termed minisequencing, the target-dependent addition by a polymerase of a specific nucleotide immediately downstream (3′) to a single primer is used to determine which allele is present (U.S. Pat. No. 5,846,710). Using this method, several SNPs can be analyzed in parallel by separating locus specific primers on the basis of size via electrophoresis and determining allele specific incorporation using labeled nucleotides.
[0084] Determination of individual SNPs using solid phase minisequencing has been described by Syvanen et al., Am. J. Hum. Genet., 52:46-59, 1993. In this method the sequence including the polymorphic site is amplified by PCR using one amplification primer which is biotinylated on its 5′ end. The biotinylated PCR products are captured in streptavidin-coated microtitration wells, the wells washed, and the captured PCR products denatured. A sequencing primer is then added whose 3′ end binds immediately prior to the polymorphic site, and the primer is elongated by a DNA polymerase with one single labeled DINP complementary to the nucleotide at the polymorphic site. After the elongation reaction, the sequencing primer is released and the presence of the labeled nucleotide detected. Alternatively, dye labeled dideoxynucleoside triphosphates (ddNTPs) can be used in the elongation reaction (U.S. Pat. No. 5,888,819; Shumaker et al., Human Mut., 7:346-354, 1996). In this method, incorporation of the ddNTP is determined using an automatic gel sequencer.
[0085] Minisequencing has also been adapted for use with microarrals (Shumaker et al., Human Mut., 7:346-354, 1996). In this case, elongation (extension) primers are attached to a solid support such as a glass slide. Methods for construction of oligonucleotide arrays are well known to those of ordinary skill in the art and can be found, for example, in Nature Genetics, Suppl., Vol. 21, January, 1999. PCR products are spotted on the array and allowed to anneal. The extension (elongation) reaction is carried out using a polymerase, a labeled dNTP and noncompeting ddNTPs. Incorporation of the labeled dNTP is then detected by the appropriate means. In a variation of this method suitable for use with multiplex PCR, extension is accomplished with the use of the appropriate labeled ddNTP and unlabeled ddNTPs (Pastinen et al., Genome Res., 7:606-614, 1997).
[0086] Solid phase minisequencing has also been used to detect multiple polymorphic nucleotides from different templates in an undivided sample (Pastinen et al., Clin. Chem., 42:1391-1397, 1996). In this method, biotinylated PCR products are captured on the avidin-coated manifold support and rendered single stranded by alkaline treatment. The manifold is then placed serially in four reaction mixtures containing extension primers of varying lengths, a DNA polymerase and a labeled ddNTP, and the extension reaction allowed to proceed. The manifolds are inserted into the slots of a gel containing formamide which releases the extended primers from the template. The extended primers are then identified by size and fluorescence on a sequencing instrument.
[0087] Fluorescence resonance energy transfer (FRET) has been used in combination with minisequencing to detect SNPs (U.S. Pat. No. 5,945,283; Chen et al., Proc. Natl. Acad. Sci. USA, 94:10756-10761, 1997). In this method, the extension primers are labeled with a fluorescent dye, for example fluorescein. The ddNTPs used in primer extension are labeled with an appropriate FRET dye. Incorporation of the ddNTPs is determined by changes in fluorescence intensities.
[0088] The above discussion of methods for the detection of SNPs is exemplary only and is not intended to be exhaustive. Those of ordinary skill in the art will be able to envision other methods for detection of SNPs that are within the scope and spirit of the present invention.
[0089] In one embodiment the present invention provides a method for diagnosing a genetic predisposition for a disease. In this method, a biological sample is obtained from a subject. The subject can be a human being or any vertebrate animal. The biological sample must contain polynucleotides and preferably genomic DNA. Samples that do not contain genomic DNA, for example, pure samples of mammalian red blood cells, are not suitable for use in the method. The form of the polynucleotide is not critically important such that the use of DNA, cDNA, RNA or mRNA is contemplated within the scope of the method. The polynucleotide is then analyzed to detect the presence of a genetic variant where such variant is associated with an increased risk of developing a disease, condition or disorder, and in particular HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder. In one embodiment, the genetic variant is at one of the polymorphic sites contained in Table 17. In another embodiment, the genetic variant is one of the variants contained in Table 17 or the complement of any of the variants contained in Table 17. Any method capable of detecting a genetic variant, including any of the methods previously discussed, can be used. Suitable methods include, but are not limited to, those methods based on sequencing, mini sequencing, hybridization, restriction fragment analysis, oligonucleotide ligation, or allele specific PCR.
[0090] The present invention is also directed to an isolated nucleic acid sequence of at least 10 contiguous nucleotides from SEQ ID NO: 1, or the complements of SEQ ID NO: 1. In one preferred embodiment, the sequence contains at least one polymorphic site associated with a disease, and in particular HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder. In one embodiment, the genetic variant is at one of the polymorphic sites contained in Table 17. In another embodiment, the genetic variant is one of the variants contained in Table 17 or the complement of any of the variants contained in Table 17. In yet another embodiment, the polymorphic site, which may or may not also include a genetic variant, is located at the 3′ end of the polynucleotide. In still another embodiment, the polynucleotide further contains a detectable marker. Suitable markers include, but are not limited to, radioactive labels, such as radionuclides, fluorophores or fluorochromes, peptides, enzymes, antigens, antibodies, vitamins or steroids.
[0091] The present invention also includes kits for the detection of polymorphisms associated with diseases, conditions or disorders, and in particular HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DID, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder. The kits contain, at a minimum, at least one polynucleotide of at least 10 contiguous nucleotides of SEQ ID NO 1, or the complements of SEQ ID NO: 1. In one embodiment, the genetic variant is at one of the polymorphic sites contained in Table 17. Alternatively the 3′ end of the polynucleotide is immediately 5′ to a polymorphic site, preferably a polymorphic site selected from the sites in Table 17. In another embodiment, the genetic variant is one of the variants contained in Table 17 or the complement of any of the variants contained in Table 17. In still another embodiment, the genetic variant is located at the 3′ end of the polynucleotide. In yet another embodiment, the polynucleotide of the kit contains a detectable label. Suitable labels include, but are not limited to, radioactive labels, such as radionuclides, fluorophores or fluorochromes, peptides, enzymes, antigens, antibodies, vitamins or steroids.
[0092] In addition, the kit may also contain additional materials for detection of the polymorphisms. For example, and without limitation, the kits may contain buffer solutions, enzymes, nucleotide triphosphates, and other reagents and materials necessary for the detection of genetic polymorphisms. Additionally, the kits may contain instructions for conducting analyses of samples for the presence of polymorphisms and for interpreting the results obtained.
[0093] In yet another embodiment the present invention provides a method for designing a treatment regime for a patient having a disease, condition or disorder and in particular HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder caused either directly or indirectly by the presence of one or more single nucleotide polymorphisms. In this method genetic material from a patient, for example, DNA, cDNA, RNA or mRNA is screened for the presence of one or more SNPs associated with the disease of interest. Depending on the type and location of the SNP, a treatment regime is designed to counteract the effect of the SNP.
[0094] Alternatively, information gained from analyzing genetic material for the presence of polymorphisms can be used to design treatment regimes involving gene therapy. For example, detection of a polymorphism that either affects the expression of a gene or results in the production of a mutant protein can be used to design an artificial gene to aid in the production of normal, wild type protein or help restore normal gene expression. Methods for the construction of polynucleotide sequences encoding proteins and their associated regulatory elements are well know to those of ordinary skill in the art. Once designed, the gene can be placed in the individual by any suitable means known in the art ( Gene Therapy Technologies, Applications and Regulations, Meager, ed., Wiley, 1999; Gene Therapy: Principles and Applications, Blankenstein, ed., Birkhauser Verlag, 1999; Jain, Textbook of Gene Therapy, Hogrefe and Huber, 1998).
[0095] The present invention is also useful in designing prophylactic treatment regimes for patients determined to have an increased susceptibility to a disease, condition or disorder, and in particular HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HTN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma, COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder due to the presence of one or more single nucleotide polymorphisms. In this embodiment, genetic material such as DNA, cDNA, RNA or mRNA, is obtained from a patient and screened for the presence of one or more SNPs associated either directly or indirectly to a disease, condition, disorder or other pathological condition. Based on this information, a treatment regime can be designed to decrease the risk of the patient developing the disease. Such treatment can include, but is not limited to, surgery, the administration of pharmaceutical compounds or nutritional supplements, and behavioral changes such as improved diet, increased exercise, reduced alcohol intake, smoking cessation, etc.
EXAMPLES
[0096] The positions of the single nucleotide polymorphisms (SNPs) pre given according to the numbering scheme in GenBank Accession Number J05008.1. thus, all nucleotides will be positively numbered, rather than bear negative numbers reflecting their position upstream from the transcription initiation site, a scheme often used for promoters. The two numbering systems can be easily interconverted, if necessary. GenBank sequences can be found at http://www.nrbi.nlm.nih.gov/
[0097] In the following examples, SNPs are written as “reference sequence nucleotide”→“variant nucleotide.” Changes in nucleotide sequences are indicated in bold print. The standard nucleotide abbreviations are used in which A=adenine, C=cytosine, G=guanine, T=thymine, M=A or C, R=A or G, W=A or T, S=C or G, Y=C or T, K=G or T, V=A or C or G, H=A or C or T; D=A or G or T; B=C or G or T; N=A or C or G or T.
Example 1
Detection of Novel Polymorphisms by Direct Sequencing of Leukocyte Genomic DNA
[0098] Leukocytes were obtained from human whole blood collected with EDTA as an anticoagulant. Blood was obtained from a group of black men, black women, white men, and white women without any known disease. Blood was also obtained from individuals with HTN, ESRD due to HTN, NIDDM, ESRD due to NIDDM, lung cancer, breast cancer, prostate cancer, colon cancer, ASPVD due to HEN, CVA due to HTN, cataracts due to HTN, HTN CM, MI due to HTN, ASPVD due to NIDDM, CVA due to NIDDM, Ischemic CM, Ischemic CM with NIDDM, MI due to NIDDM, afib without valvular disease, alcohol abuse, anxiety, asthma,.COPD, cholecystectomy, DJD, ESRD and frequent de-clots, ESRD due to FSGS, ESRD due to IDDM, or seizure disorder as indicated in the tables below.
[0099] Genomic DNA was purified from the collected leukocytes using standard protocols well known to those of ordinary skill in the art of molecular biology (Ausubel et al., Short Protocol in Molecular Biology, 3 rd ed., John Wiley and Sons, 1995; Sambrook et al., Molecular Cloning, Cold Spring Harbor Laboratory Press, 1989; and Davis et al., Basic Methods in Molecular Biology, Elsevier Science Publishing, 1986). One hundred nanograms of purified genomic DNA were used in each PCR reaction.
[0100] Standard PCR reaction conditions were used. Methods for conducting PCR are well known in the art and can be found, for example, in U.S. Pat. Nos. 4,965,188, 4,800,159, 4,683,202, and 4,683,195; Ausbel et al., eds., Short Protocols in Molecular Biology, 3 rd ed., Wiley, 1995; and Innis et al., eds., PCR Protocols, Academic Press, 1990.
[0101] The first SNP T2239→G can be identified by PCR amplification of a specific region of the endothelin-1 promoter. The sequence of the sense primer was 5′-CTC CAT CCC CAG AAA AAC TG-3′, corresponding to nucleotides 2113 to 2132, inclusive. (SEQ ID NO: 2). The sequence of the anti-sense primer is 5′-AAG GAA GGT GGT GCT GAG AA-3′ corresponding to nucleotides 2490 to 2509, inclusive. (SEQ ID NO: 3). The PCR product spanned positions 2113 to 2509, inclusive, of the EDN1 gene.
[0102] The second SNP A2657→C can be identified by PCR amplification of a specific region of the endothelin-1 promoter. The sense primer was 5′-GGG GGA TTT CAA GGT TAG AT -3′ (SEQ ID NO: 4). The anti-sense primer was 5′-GAG AAG CCC CGA TAA GTT CTT T-3′ (SEQ ID NO: 5). The PCR product thus produced spanned positions 2390 to 2924 of the human EDN-1 gene (SEQ ID NO: 1).
[0103] The PCR reaction contained a total volume of 20 microliters (μl), consisting of 10 μl of a premade PCR reaction mix (Sigma “JumpStart Ready Mix with RED Taq Polymerase”). Primers at 10 μM were diluted to a final concentration of 0.3 μM in the PCR reaction mix. Approximately 25 ng of template leukocyte genomic DNA was used for each PCR amplification. After an initial 5 minutes denaturation at 94° C., 35 cycles were performed consisting of 45 seconds of denaturation at 94° C., 45 seconds of hybridization at 62° C., 45 seconds of extension at 72° C., followed by a final extension step of 10 minutes at 72° C.
[0104] Post-PCR clean-up was performed as follows. PCR reactions were cleaned to remove unwanted primer and other impurities such as salts, enzymes, and unincorporated nucleotides that could inhibit sequencing. One of the following clean-up kits was used: Qiaquick-96 PCR Purification Kit (Qiagen) or Multiscreen-PCR Plates (Millipore, discussed below).
[0105] When using the Qiaquick protocol, PCR samples were added to the 96-well Qiaquick silica-gel membrane plate and a chaotropic salt, supplied as “PB Buffer,” was then added to each well. The PB Buffer caused the DNA to bind to the membrane. The plate was put onto the Qiagen vacuum manifold and vacuum was applied to the plate in order to pull sample and PB Buffer through the membrane. The filtrate was discarded. Next, the samples were washed twice using “PE Buffer.” Vacuum pressure was applied between each step to remove the buffer. Filtrate was similarly discarded after each wash. After the last PE Buffer wash, maximum vacuum pressure was applied to the membrane plate to generate maximum airflow through the membrane in order to evaporate residual ethanol left from the PE Buffer. The clean PCR product was then eluted from the filter using EB Buffer.” The filtrate contained the cleaned PCR product ad was collected. All buffers were supplied as part of the Qiaquick-96 PCR-Purification Kit. The vacuum manifold was also purchased from Qiagen for exclusive use with the Qiaquick-96 Purification Kit.
[0106] When using the Millipore Multiscreen-PCR Plates, PCR samples were loaded into the wells of the Multiscreen-PCR Plate and the plate was then placed on a Millipore vacuum manifold. Vacuum pressure was applied for 10 minutes, and the filtrate was discarded. The plate was then removed from the vacuum manifold and 100 μl of Milli-Q water was added to each well to rehydrate the DNA samples. After shaking on a plate shaker for 5 minutes, the plate was replaced on the manifold and vacuum pressure was applied for 5 minutes. The filtrate was again discarded. The plate was removed and 60 μl Milli-Q water was added to each well to again rehydrate the DNA samples. After shaking on a plate shaker for 10 minutes, the 60 μl of cleaned PCR product was transferred from the Multiscreen-PCR plate to another 96-well plate by pipetting. The Millipore vacuum manifold was purchased from Millipore for exclusive use with the Multiscreen-PCR plates.
[0107] Cycle sequencing was performed on the clean PCR product using an ABI Prism Big Dye Terminator Cycle Sequencing Ready Reaction kit (Perkin-Elmer). For a total volume of 20 μl, the following reagents were added to each well of a 96-well plate: 2.0 μl Terminator Ready Reaction mix, 3.0 μl 5× Sequencing Buffer (ABI), 5-10 μl template (30-90 ng double stranded DNA), 3.2 pM primer (primer used was the forward primer from the PCR reaction), and Milli-Q water to 20 μl total volume. The reaction plate was placed into a Hybaid thermal cycler block and programmed as follows: ×1 cycle: 1 degree/sec thermal ramp to 94° C., 94° C. for 1 min; ×35 cycles: 1 degree/sec thermal ramp to 94° C., then 94° C. for 10 sec, followed by 1 degree/sec thermal ramp to 50° C., then 50° C. for 10 sec, followed by 1 degree/sec thermal ramp to 60° C., then 60° C. for 4 minutes.
[0108] The cycle sequencing reaction product was cleaned up to remove the unincorporated dye-labeled terminators that can obscure data at the beginning of the sequence. A precipitation protocol was used. To each sequencing reaction in the 96-well plate, 20 μl of Milli-Q water and 60 μl of 100% isopropanol was added. The plate was left at room temperature for at least 20 minutes to precipitate the extension products. The plate was spun in a plate centrifuge (Jouan) at 3,000×g for 30 minutes.
[0109] Without disturbing the pellet, the supernatant was discarded by inverting the plate onto several paper tissues (Kimwipes) folded to the size of the plate. The inverted plate, with Kimwipes in place, was placed into the centrifuge (Jouan) and spun at 700×g for 1 minute. The Kimwipes were discarded and the samples were loaded onto a sequencing gel.
[0110] Approximately 1 μi of sequencing product was loaded into each well of a 96-lane 5% Long Ranger (FMC single pack) gel. The running buffer consisted of 1×TBE. The glass plates consisted of ABI 48-cm plates for use with a 96-lane 0.4 mm Mylar shark-tooth comb. A semi-automated ABI Prism 377-96 DNA sequencer was used (ABI 377 with 96-lane, Big Dye upgrades). Sequencing run settings were as follows: run module 48E-1200, 8 hr collection time, 2400 V electrophoresis voltage, 50 mA electrophoresis current, 200 W electrophoresis power, CCD offset of 0, gel temperature of 51° C., 40 mW laser power, and CCD gain of 2.
[0111] Pyrosequencing is another method of sequencing DNA by synthesis, where the addition of one of the four dNTPs that correctly matches the complementary base on the template strand is detected. Detection occurs via utilization of the pyrophosphate molecules liberated upon base addition to the elongating synthetic strand. The pyrophosphate molecules are used to make ATP, which in turn drives the emission of photons in a luciferin/luciferase reaction, and these photons are detected by the instrument. A Luc96 Pyrosequencer was used under default operating conditions supplied by the manufacturer. Primers were designed to anneal within 5 bases of the polymorphism, to serve as sequencing primers.
[0112] Patient genomic DNA was subject to PCR using amplifying primers that amplify an approximately 200 base pair amplicon containing the polymorphisms of interest. One of the amplifying primers, whose orientation is opposite to the sequencing primer, was biotinylated. This allowed selection of single stranded template for pyrosequencing, whose orientation is complementary to the sequencing primer. Amplicons prepared from genomic DNA were isolated by binding to streptavidin-coated magnetic beads. After denaturation in NaOH, the biotinylated strands were separated from their complementary strands using magnetics. After washing the magnetic beads, the biotinylated template strands still bound to the beads were transferred into 96-well plates. The sequencing primers were added, annealing was carried out at 95° for 2 minutes, and plates were placed in the Pyrosequencer. The enzymes, substrates and dNTPs used for synthesis and pyrophosphate detection were added to the instrument immediately for to sequencing.
[0113] The Luc96 software requires definition of a program of adding the four dNTPs that is specific for the location of the sequencing primer, the DNA composition flanking the SNP, and the two possible alleles at the polymorphic locus. This order of adding the bases generates theoretical outcomes of light intensity patterns for each of the two possible homozygous states and the single heterozygous state. The Luc96 software then compares the actual outcome to the theoretical outcome and calls a genotype for each well. Each sample is also assigned one of three confidence scores: pass, uncertain, fail. The results for each plate are output as a text file and processed in Excel using a Visual Basic program to generate a report of genotype and allele frequencies for the various disease and population cell groupings represented on the 96 well plate.
[0114] Prediction of potential transcription binding factor sites was performed using a commercially available software program [GENOMATIX MatInspector Professional; URL: http://genomatix.gsf.de/cgi-bin/matinspector/matinspector.pl ; Quandt et al., Nucleic Acids Res., 23: 4878-4884 (1995)].
TABLE 1 GROUP I ALLELE FREQUENCY T G CONTROL Black men (n = 22 chromosomes) 13 (59%) 9 (41%) Black women (n = 22 chromosomes) 11 (50%) 11 (50%) White men (n = 18 chromosomes) 16 (89%) 2 (11%) White women (n = 24 chromosomes) 21 (88%) 3 (13%) DISEASE BREAST CANCER Black women (n = 24 chromosomes) 12 (50%) 12 (50%) White women (n = 22 chromosomes) 19 (86%) 3 (14%) LUNG CANCER Black men (n = 24 chromosomes) 17 (71%) 7 (29%) Black women (n = 4 chromosomes) 1 (25%) 3 (75%) White men (n = 22 chromosomes) 15 (68%) 7 (32%) White women (n = 20 chromosomes) 14 (70%) 6 (30%) PROSTATE CANCER Black men (n = 24 chromosomes) 13 (54%) 11 (46%) White men (n = 24 chromosomes) 17 (71%) 7 (29%) NIDDM Black men (n = 20 chromosomes) 14 (70%) 6 (30%) Black women (n = 20 chromosomes) 14 (70%) 6 (30%) White men (n = 22 chromosomes) 16 (73%) 6 (27%) White women (n = 20 chromosomes) 13 (65%) 7 (35%) ESRD due to NIDDM Black men (n = 8 chromosomes) 6 (75%) 2 (25%) Black women (n = 20 chromosomes) 14 (70%) 6 (30%) White men (n = 20 chromosomes) 18 (90%) 2 (10%) White women (n = 16 chromosomes) 16 (100%) 0 (0%)
[0115] [0115] TABLE 2 GROUP II ALLELE FREQUENCY Disease Race CHROMOSOMES N T N G Controls African-American 90 61 67.8% 29 32.2% Caucasian 88 76 86.4% 12 13.6% Colon cancer African-American 44 31 70.5% 13 29.5% Caucasian 44 35 79.5% 9 20.5% Lung cancer African-American 40 26 65.0% 14 35.0% Caucasian 44 31 70.5% 13 29.5% Hypertension African-American 48 31 64.6% 17 35.4% Caucasian 44 40 90.9% 4 9.1% CVA due to HTN Caucasian 46 38 82.6% 8 17.4% ESRD due to HTN African-American 42 26 61.9% 16 38.1% Caucasian 48 38 79.2% 10 20.8% HTN CM African-American 48 30 62.5% 18 37.5% Caucasian 46 38 82.6% 8 17.4% NIDDM African-American 42 32 76.2% 10 23.8% ASPVD due to NIDDM Caucasian 46 38 82.6% 8 17.4% CVA due to NIDDM Caucasian 44 39 88.6% 5 11.4% ESRD due to NIDDM Caucasian 46 35 76.1% 11 23.9% Ischemic CM with NIDDM African-American 48 30 62.5% 18 37.5% Caucasian 48 42 87.5% 6 12.5% MI due to NIDDM Caucasian 48 37 77.1% 11 22.9% Afib without valvular disease African-American 48 29 60.4% 19 39.6% Caucasian 48 40 83.3% 8 16.7% Alcohol abuse African-American 48 22 45.8% 26 54.2% Caucasian 48 36 75.0% 12 25.0% Asthma Caucasian 48 41 85.4% 7 14.6% COPD African-American 40 33 82.5% 7 17.5% Caucasian 42 34 81.0% 8 19.0% ESRD due to FSGS Caucasian 42 33 78.6% 9 21.4%
[0116] [0116] TABLE 3 GROUP I GENOTYPE FREQUENCIES T/T T/G G/G CONTROLS Black men (n = 11) 4 (36%) 5 (45%) 2 (18%) Black women (n = 11) 4 (36%) 3 (27%) 4 (36%) White men (n = 9) 8 (89%) 0 (0%) 1 (11%) White women (n = 12) 9 (75%) 3 (25%) 0 (0%) DISEASE BREAST CANCER Black women (n = 12) 4 (33%) 4 (33%) 4 (33%) White women (n = 11) 8 (73%) 3 (27%) 0 (0%) LUNG CANCER Black men (n = 12) 6 (50%) 5 (42%) 1 (8%) Black women (n = 2) 0 (0%) 1 (50%) 1 (50%) White men (n = 11) 5 (45%) 5 (45%) 1 (9%) White women (n = 10) 5 (50%) 4 (40%) 1 (10%) PROSTATE CANCER Black men (n = 12) 3 (25%) 7 (58%) 2 (17%) White men (n = 12) 5 (42%) 7 (58%) 0 (0%) NIDDM Black men (n = 10) 6 (60%) 2 (20%) 2 (20%) Black women (n = 10) 5 (50%) 4 (40%) 1 (10%) White men (n = 11) 7 (64%) 2 (18%) 2 (18%) White women (n = 10) 5 (50%) 3 (30%) 2 (20%) ESRD due to NIDDM Black men (n = 4) 2 (50%) 2 (50%) 0 (0%) Black women (n = 10) 5 (50%) 4 (40%) 1 (10%) White men (n = 10) 8 (80%) 2 (20%) 0 (0%) White women (n = 8) 8 (100%) 0 (0%) 0 (0%)
[0117] [0117] TABLE 4 GROUP II GENOTYPE FREQUENCIES Disease Race People N T/T N T/G N G/G Controls African-American 45 17 37.8% 27 60.0% 1 2.2% Caucasian 44 33 75.0% 10 22.7% 1 2.3% Colon cancer African-American 22 10 45.5% 11 50.0% 1 4.5% Caucasian 22 15 68.2% 5 22.7% 2 9.1% Hypertension African-American 24 10 41.7% 11 45.8% 3 12.5% Caucasian 22 18 81.8% 4 18.2% 0 0.0% CVA due to HTN Caucasian 23 16 69.6% 6 26.1% 1 4.3% ESRD due to HTN African-American 21 9 42.9% 8 38.1% 4 19.0% Caucasian 24 14 58.3% 10 41.7% 0 0.0% HTN CM African-American 24 10 41.7% 10 41.7% 4 16.7% Caucasian 23 16 69.6% 6 26.1% 1 4.3% NIDDM African-American 21 14 66.7% 4 19.0% 3 14.3% ASPVD due to NIDDM Caucasian 23 16 69.6% 6 26.1% 1 4.3% CVA due to NIDDM Caucasian 22 17 77.3% 5 22.7% 0 0.0% ESRD due to NIDDM Caucasian 23 14 60.9% 7 30.4% 2 8.7% Ischemic CM with NIDDM African-American 24 10 41.7% 10 41.7% 4 16.7% Caucasian 24 18 75.0% 6 25.0% 0 0.0% MI due to NIDDM Caucasian 24 13 54.2% 11 45.8% 0 0.0% Afib without valvular disease African-American 24 9 37.5% 11 45.8% 4 16.7% Caucasian 24 16 66.7% 8 33.3% 0 0.0% Alcohol abuse African-American 24 7 29.2% 8 33.3% 9 37.5% Caucasian 24 14 58.3% 8 33.3% 2 8.3% Asthma Caucasian 24 17 70.8% 7 29.2% 0 0.0% COPD African-American 20 13 65.0% 7 35.0% 0 0.0% Caucasian 21 14 66.7% 6 28.6% 1 4.8% ESRD due to FSGS Caucasian 21 12 57.1% 9 42.9% 0 0.0%
[0118] The susceptibility allele is indicated below, as well as the odds ratio (OR). The allele which is present more often in the given disease category was chosen as the susceptibility allele. For example, the G allele was chosen as the susceptibility allele for black women with breast cancer because more of the individuals in that category had the G allele than had the T allele. Where there was a “0” in a cell which produced a 0 in the denominator, Haldane's correction (multiplying all cells by 2 and adding 1) was used. If the odds ratio (OR) was ≧1.5, the 95% confidence interval (C.I.) is also given.
[0119] An odds ratio of 1.5 was chosen as the threshold of significance based on the recommendation of Austin et al. in Epidemiol. Rev., 16:65-76, 1994. “[E]pidemiology in general and case-control studies in particular are not well suited for detecting weak associations (odds ratios <1.5).” Id. at 66.
[0120] An example of the allele-specific odds ratio calculation is given below:
[0121] Lung Cancer: Black men
Cases Controls T 17 13 G 7 9
[0122] The odds ratio for the T allele is (17)(9)/(7)(13)=1.7. Therefore, black men with the T allele have a 1.7 fold higher risk of developing lung cancer than black men without the T allele. Odds ratios of 1.5 or higher are highlighted below.
TABLE 5 GROUP I ALLELE-SPECIFIC ODDS RATIOS SUSCEPTIBILITY DISEASE ALLELE OR 95% C.I. Breast Cancer Black women G 1.0 White women T 0.9 Lung Cancer Black men T 1.7 0.5-5.7 Black women G 3.0 0.3-33.5 White men G 3.7 0.7-20.9 White women G 3.0 0.6-14.0 Prostate Cancer Black men G 1.3 White men G 3.3 0.6-18.3 NIDDM Black men T 1.6 0.4-5.8 Black women T 2.3 0.7-8.3 White men G 3.0 0.5-17.2 White women G 3.8 0.8-17.2 ESRD due to NIDDM Black men T 1.3* Black women T 1.0* White men T 3.4* 0.6-19 White women T 18.3* 2.3-148
[0123] [0123] TABLE 6 GROUP II ALLELE-SPECIFIC ODDS RATIOS Lower Upper Risk Odds Limit Limit Disease Race Allele Ratio 95% CI 95% CI Haldane Colon cancer Caucasian C 1.6 0.6 4.2 Hypertension Caucasian A 1.6 0.5 5.2 CVA due to HTN* Caucasian C 2.1 0.6 7.6 ESRD due to HTN* African-American C 1.1 0.5 2.6 Caucasian C 2.6 0.8 9.1 Ischemic CM with NIDDM* 1 Caucasian A 2.1 0.7 6.2 Afib without valvular disease Caucasian C 1.3 0.5 3.4 Alcohol abuse Caucasian C 2.1 0.9 5.2 Asthma Caucasian C 1.1 0.4 3.0 COPD Caucasian C 1.5 0.6 4.0 ESRD due to FSGS Caucasian C 1.7 0.7 4.5
[0124] Genotype-Specific Odds Ratios
[0125] The susceptibility allele (S) is indicated; the alternative allele at this locus is defined as the protective allele (P). Also presented is the odds ratio (OR) for each genotype (SS, SP; the odds ratio for the PP genotype is 1, since it is the reference group, and is not presented separately). For odds ratios ≧1.5, the 95% confidence interval (C.I.) is also given, in parentheses. Where there was a “0” in a cell which produced a 0 in the denominator, Haldane's correction (multiplying all cells by 2 and adding 1) was used. As discussed above, an odds ratio of 1.5 is chosen as the threshold of significance based on the recommendation of Austin H et al. (Epidemiol. Rev. 16:65-76, 1994).
[0126] An example of an odds ratio calculation is worked below, assuming that T is the susceptibility allele (S), and G is the protective allele (P).
[0127] Black men: Lung Cancer
Cases Controls Odds Ratio TT(SS) 6 4 (6)(2)/(1)(4) = 3.0 TG(SP) 5 5 (5)(2)/(1)(5) = 2.0 GG(PP) 1 2 1.0 (by definition)
[0128] The odds ratios for individual genotypes are given below. Odds ratios of 1.5 or higher are high-lighted below.
TABLE 7 GROUP I GENOTYPE-SPECIFIC ODDS RATIOS SUSCEPTI- BILITY DISEASE ALLELE OR(SS) OR(SP) Lung Cancer Black men T 3.0 (0.2-45.2) 2.0 (0.1-29.8) Black women G 3.0 (0.3-34.6) 3.9 (0.3-45.6) White men G 1.5 (0.3-9.1) 17.0 (1.9-151) White women G 5.2 (0.5-56.1) 2.2 (0.6-7.6) Prostate Cancer White men G 0.5 23.2 (2.7-201) NIDDM Black men T 1.5 (0.1-15.5) 0.4 Black women T 5.0 (0.4-64.4) 5.3 (0.4-75.8) White men G 1.9 (0.4-9.3) 5.7 (0.6-54.1) White women G 8.6 (0.9-83.8) 1.7 (0.5-6.2) ESRD due to NIDDM White men T 5.7 (0.6-54.1)* 5.0 (0.4-59.7)* White women T 7.7 (0.8-75.3)* 0.7*
[0129] [0129] TABLE 8 GROUP II GENOTYPE-SPECIFIC ODDS RATIOS RISK SS SP Disease Race ALLELE O.R. HALDANE O.R. HALDANE Colon cancer Caucasian C 0.2 0.3 Hypertension Caucasian A 1.7 H 1.3 H CVA due to HTN* Caucasian C 0.0 0.0 ESRD due to HTN* African-American C 0.7 0.5 Caucasian C 0.8 H 2.3 H Ischemic CM with NIDDM* 1 Caucasian A 1.4 H 0.6 H Afib without valvular disease Caucasian C 1.5 H 2.4 H Alcohol abuse Caucasian C 0.2 0.4 Asthma Caucasian C 1.6 H 2.1 H COPD Caucasian C 0.4 0.6 ESRD due to FSGS Caucasian C 1.1 H 2.7 H
[0130] PCR and sequencing were conducted as described in Example 1. The primers used were the same as in Example 1. The control samples are in good agreement with Hardy-Weinberg equilibrium, as follows:
[0131] For the Group I diseases, a frequency of 0.59 for the T allele (“p”) and 0.41 for the G allele (“q”) among black male control individuals predicts genotype frequencies of 35% T/T, 48% T/G, and 17% G/G at Hardy-Weinberg equilibrium (p 2 +2pq+q 2 =1). The observed genotype frequencies were 36% T/T, 45% T/G, and 18% C/C, in close agreement with those predicted for Hardy-Weinberg equilibrium.
[0132] A frequency of 0.50 for the T allele (“p”) and 0.50 for the G allele (“q”) among black female control individuals predicts genotype frequencies of 25% T/T, 50% T/G, and 25% G/G at Hardy-Weinberg equilibrium (p 2 +2pq+q 2 =1). The observed genotype frequencies were 36% T/T, 27% T/G, and 36% C/C, in rather distant agreement with those predicted for Hardy-Weinberg equilibrium.
[0133] A frequency of 0.89 for the T allele (“p”) and 0.11 for the G Ilele (“q”) among white male control individuals predicts genotype frequencies of 79% T/T, 20% T/G, and 1% G/G at Hardy-Weinberg equilibrium (p 2 +2pq+q 2 =1). The observed genotype frequencies were 89% T/T, 0% T/G, and 11% C/C, in rather distant agreement with those predicted for Hardy-Weinberg equilibrium.
[0134] A frequency of 0.88 for the T allele (“p”) and 0.13 for the G allele (“q”) among white female control individuals predicts genotype frequencies of 77% T/T, 21% T/G, and 2% G/G at Hardy-Weinberg equilibrium (p 2 +2pq+q 2 =1). The observed genotype frequencies were 75% T/T, 25% T/G, and 0% C/C, in close agreement with those predicted for Hardy-Weinberg equilibrium.
[0135] For the Group II diseases, a frequency of 0.68 for the T allele (“p”) and 0.32 for the G allele (“q”,) among African American control individuals predicts genotype frequencies of 45.9% T/T, 44.0% TMG, and 10.1% G/G at Hardy-Weinberg equilibrium (p 2 +2pq+q 2 =1). The observed genotype frequencies were 37.8% T/T, 60.0% T/G, and 2.2% G/G, in distant agreement with those predicted for Hardy-Weinberg equilibrium.
[0136] A frequency of 0.86 for the T allele (“p”) and 0.14 for the G allele (“q”) among Caucasian control individuals predicts genotype frequencies of 74.6% T/T, 23.5% T/G, and 1.9% G/G at Hardy-Weinberg equilibrium (p 2 +2pq+q 2 =1). The observed genotype frequencies were 75.0% T/T, 22.7% T/G, and 2.3% G/G, in excellent agreement with those predicted for Hardy-Weinberg equilibrium.
[0137] Using an allele-specific odds ratio of 1.5 or greater as a practical level of significance (see Austin H et al., discussed above), the following observations can be made.
[0138] For black men with lung cancer, the odds ratio for the T allele as a risk factor for disease is 1.7 (95% CI, 0.5-5.7). The odds ratio for the homozygote (TT) is 3.0 (95% CI, 0.2- 45.2). The heterozygote (TG genotype) has an odds ratio of 2.0 (95% C.I., 0.1-29.8). These data suggest that the T allele behaves as a dominant allele, with an additive effect of allele dosage (2.0+2.0−1=3.0).
[0139] For black women with lung cancer, the odds ratio for the G allele as a risk factor for disease is 3.0 (95% CI, 0.3-33.5). The odds ratio for the homozygote (GG) is 3.0 (95% CI, 0.3-34.6). The heterozygote (GT genotype) has an odds ratio of 3.9 (95% C.I., 0.3-45.6). T hese data suggest that the G allele behaves as a dominant allele, with no additional effect of having two copies of the G allele (GG homozygote) as compared with having only one copy (GT heterozygote).
[0140] For white men with lung cancer, the odds ratio for the G allele as a risk factor for disease is 3.7 (95% CI, 0.7-20.9). The odds ratio for the homozygote (GG) is only 1.5 (95% CI, 0.3-9.1), whereas the heterozygote (GT genotype) has a remarkable odds ratio of 17.0 (95% C.I., 1.9-151). These data suggest that the G allele behaves as a codominant allele.
[0141] For white women with lung cancer, the odds ratio for the G allele as a risk factor for disease is 3.0 (95% CI, 0.6-14.0). The odds ratio for the homozygote (GG) is 5.2 (95% CI, 0.5-56.1), while the heterozygote (GT genotype) has an odds ratio of 2.2 (95% C.I., 0.6-7.6). These data suggest that the G allele behaves as a dominant allele with more than an additive effect of allele copy number (2.2+2.2−1<5.2).
[0142] For white men with prostate cancer, the odds ratio for the G allele as a risk factor for disease is 3.3 (95% CI, 0.6-18.3). The odds ratio for the homozygote (GG) is actually less than 1, whereas the heterozygote (GT genotype) has a remarkable odds ratio of 23.2 (95% C.I., 2.7-201). These data suggest that the G allele behaves as a codominant allele.
[0143] For black men with NIDDM, the odds ratio for the T allele as a risk factor for disease is 1.6 (95% CI, 0.4-5.8). The odds ratio for the homozygote (TT) is 1.5 (95% CI, 0.1-15.5), whereas the heterozygote (TG genotype) has an odds ratio of less than 1. These data suggest that the T allele behaves as a recessive allele.
[0144] For black women with NIDDM, the odds ratio for the T allele as a risk factor for disease is 2.3 (95% CI, 0.7-8.3). The odds ratio for the homozygote (TT) is 5.0 (95% CI, 0.4-64.4), whereas the heterozygote (TG genotype) has an odds ratio of 5.3 (95% CI, 0.4-75.8). These data suggest that the T allele behaves as a classical dominant allele.
[0145] For white men with NIDDM, the odds ratio for the G allele as a risk factor for disease is 3.0 (95% CI, 0.5-17.2). The odds ratio for the homozygote (GG) is 1.9 (95% CI, 0.4-9.3), whereas the heterozygote (GT genotype) has an odds ratio of 5.7 (95% CI, 0.6-54.1). These data suggest that the G allele behaves as a codominant allele.
[0146] For white women with NIDDM, the odds ratio for the G allele as a risk factor for disease is 3.8 (95% CI, 0.8-17.2). The odds ratio for the homozygote (GG) is 8.6 (95% CI, 0.9-83.8), whereas the heterozygote (GT genotype) has an odds ratio of only 1.7 (95% CI, 0.5-6.2). These data suggest that the G allele behaves as a dominant allele, with a more than multiplicative effect of allele dosage [8.6>>(1.7)(1.7)].
[0147] For white men with ESRD due to NIDDM, the odds ratio for the T allele as a risk factor for disease is 3.4 (95% CI, 0.6-19.2) as compared with white men with NIDDM but no renal disease. The odds ratio for the homozygote (TT) is 5.7 (95% CI, 0.6-54.1), while the heterozygote (TG genotype) has a similar odds ratio of 5.0 (95% CI, 0.4-59.7). These data suggest that the T allele behaves as a classical dominant allele.
[0148] For white women with ESRD due to NIDDM, the odds ratio for the T allele as a risk factor for disease is a remarkable 18.3 (95% CI, 2.3-148) as compared with white women with NIDDM but no renal disease. The odds ratio for the homozygote (TT) is 7.7 (95% CI, 0.8-75.3), while the heterozygote (TG genotype) has an odds ratio of only 0.7. These data suggest that the T allele behaves as a classical recessive allele.
[0149] For Caucasians with alcohol abuse the odds ratio for the G allele was 2.1 (95% CI, 0.9-5.2). Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with alcohol abuse in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to alcohol abuse.
[0150] For Caucasians with colon cancer the odds ratio for the G allele was 1.6 (95 % CI, 0.6-4.2). Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with colon cancer in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to colon cancer.
[0151] For Caucasians with diabetic cardiomyopathy the odds ratio for the T allele was 2.1 (95% CI, 0.7-6.2), compared to Caucasians with MI due to NIDDM. Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with diabetic cardiomyopathy in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to diabetic cardiomyopathy.
[0152] For Caucasians with ESRD due to hypertension the odds ratio for the G allele was 2.6 (95% CI, 0.8-9.1), compared to Caucasians with hypertension only. The odds ratio for the homozygote (G/G) was 0.8 H (95% CI, 0-14.1), while the odds ratio for the heterozygote (T/G) was 2.3 H (95% CI, 0-137). These data suggest that G allele acts in a co-dominant manner in this patient population. These data further suggest that the EDN-1 gene is significantly associated with ESRD due to hypertension in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to ESRD due to hypertension.
[0153] For Caucasians with ESRD due to FSGS the odds ratio for the G allele was 1.7 (95% CI, 0.7-4.5). The odds ratio for the homozygote (G/G) was 1.1 H (95% CI, 0.1-19.7), while the odds ratio for the heterozygote (T/G) was 2.7 H (95% CI, 0.1-75). These data suggest that the G allele acts in a co-dominant manner in this patient population. These data further suggest that the EDN-1 gene is significantly associated with ESRD due to FSGS in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to ESRD due to FSGS.
[0154] For Caucasians with hypertension only the odds ratio for the T allele was 1.6 (95% CI, 0.5-5.2). The odds ratio for the homozygote (TIT ) was 1.7 H (95% CI, 0.1-28.6), while the odds ratio for the heterozygote (T/G) was 1.3 H (95% CI, 0-38). These data suggest that the T allele acts in a recessive manner in this patient population. These data further suggest that the EDN-1 gene is significantly associated with hypertension only in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to hypertension only.
[0155] For Caucasians with CVA due to HTN the odds ratio for the G allele was 2.1 (95% CI, 0.6-7.6), compared to Caucasians with hypertension only. Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with CVA due to HTN in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to CVA due to HTN.
[0156] The binding site of T-cell factor-2 alpha (TCF-2 alpha) is predicted to be disrupted by the T2239→G SNP (Quandt K et al., Nucleic Acids Res., 23:4878-4884, 1995). TCF-2 alpha binds to a core sequence of five nucleotides, 5′-K T KTC-3′ (Waterman M. L., et al. New Biology, 2(7):621-636, 1990). A TCF-2 alpha binding site, which occurs on average 3.91 times per 1000 base pairs of random genomic sequence in vertebrates, is predicted to occur at position 2236 to 2240 on the (−) strand of reference sequence J05008.1 (matrix score 1.000, with 1.000 being an identical match). The T2239→G SNP replaces the indicated T with a G within the core binding sequence.
[0157] TCF-2 alpha is a transcriptional activator in lymphoid cells, although nothing is known of its activity in other cell types. Disruption of the TCF-2 alpha core binding site is expected to result in a decreased rate of transcription of the endothelin-1 gene.
TABLE 9 GROUP I ALLELE FREQUENCIES A C CONTROL Black men (n = 46 chromosomes) 30 (65%) 16 (35%) Black women (n = 40 chromosomes) 30 (75%) 10 (25%) White men (n = 42 chromosomes) 38 (90%) 4 (10%) White women (n = 48 chromosomes) 42 (88%) 6 (13%) DISEASE Breast Cancer Black women (n = 16 chromosomes) 7 (44%) 9 (56%) White women (n = 12 chromosomes) 9 (75%) 3 (25%) Lung Cancer Black men (n = 20 chromosomes) 13 (65%) 7 (35%) Black women (n = 16 chromosomes) 11 (69%) 5 (31%) White men (n = 20 chromosomes) 13 (65%) 7 (35%) White women (n = 12 chromosomes) 8 (67%) 4 (33%) Prostate Cancer Black men (n = 16 chromosomes) 13 (81%) 3 (19%) White men (n = 18 chromosomes) 11 (61%) 7 (39%) HTN Black men (n = 18 chromosomes) 12 (67%) 6 (33%) Black women (n = 16 chromosomes) 13 (81%) 3 (19%) White men (n = 22 chromosomes) 21 (95%) 1 (5%) White women (n = 18 chromosomes) 15 (83%) 3 (17%) ESRD due to HTN Black men (n = 12 chromosomes) 10 (83%) 2 (17%) Black women (n = 10 chromosomes) 6 (60%) 4 (40%) White men (n = 14 chromosomes) 12 (86%) 2 (14%) White women (n = 4 chromosomes) 4 (100%) 0 (0%) NIDDM Black men (n = 16 chromosomes) 13 (81%) 3 (19%) Black women (n = 16 chromosomes) 11 (69%) 5 (31%) White men (n = 22 chromosomes) 16 (73%) 6 (27%) White women (n = 20 chromosomes) 15 (75%) 5 (25%) ESRD due to NIDDM Black men (n = 4 chromosomes) 3 (75%) 1 (25%) Black women (n = 18 chromosomes) 14 (78%) 4 (22%) White men (n = 16 chromosomes) 14 (88%) 2 (13%) White women (n = 10 chromosomes) 10 (100%) 0 (0%)
[0158] [0158] TABLE 10 GROUP II ALLELE FREQUENCIES Disease Race CHROMOSOMES N C N A Controls African-American 90 25 27.8% 65 72.2% Caucasian 90 15 16.7% 75 83.3% Colon cancer African-American 48 8 16.7% 40 83.3% Caucasian 44 7 15.9% 37 84.1% Hypertension African-American 42 6 14.3% 36 85.7% Caucasian 44 4 9.1% 40 90.9% ASPVD due to HTN African-American 50 10 20.0% 40 80.0% Caucasian 50 7 14.0% 43 86.0% CVA due to HTN Caucasian 48 9 18.8% 39 81.3% Cataracts due to HTN African-American 44 9 20.5% 35 79.5% HTN CM African-American 1 7 14.6% 41 85.4% Caucasian 44 5 11.4% 39 88.6% MI due to HTN African-American 42 11 26.2% 31 73.8% Caucasian 46 11 23.9% 35 76.1% NIDDM African-American 44 11 25.0% 33 75.0% Caucasian 48 13 27.1% 35 72.9% ASPVD due to NIDDM African-American 46 15 32.6% 31 67.4% Caucasian 46 8 17.4% 38 82.6% CVA due to NIDDM African-American 48 9 18.8% 39 81.3% Caucasian 46 5 10.9% 41 89.1% Ischemic CM African-American 48 11 22.9% 37 77.1% Caucasian 42 8 19.0% 34 81.0% Ischemic CM with NIDDM African-American 48 14 29.2% 34 70.8% Caucasian 48 7 14.6% 41 85.4% MI due to NIDDM African-American 48 6 12.5% 42 87.5% Caucasian 46 10 21.7% 36 78.3% Afib without valvular disease African-American 48 14 29.2% 34 70.8% Caucasian 48 8 16.7% 40 83.3% Alcohol abuse African-American 48 17 35.4% 31 64.6% Caucasian 48 12 25.0% 36 75.0% Anxiety African-American 48 16 33.3% 32 66.7% Caucasian 42 10 23.8% 32 76.2% Asthma African-American 48 11 22.9% 37 77.1% Caucasian 48 6 12.5% 42 87.5% COPD African-American 44 3 6.8% 41 93.2% Caucasian 42 8 19.0% 34 81.0% Cholecystectomy African-American 48 14 29.2% 34 70.8% Caucasian 46 7 15.2% 39 84.8% DJD African-American 40 9 22.5% 31 77.5% ESRD and frequent de-clots African-American 46 13 28.3% 33 71.7% Caucasian 42 5 11.9% 37 88.1% ESRD due to FSGS African-American 44 13 29.5% 31 70.5% Caucasian 46 10 21.7% 36 78.3% ESRD due to IDDM African-American 48 14 29.2% 34 70.8% Caucasian 44 3 6.8% 41 93.2% Seizure disorder African-American 46 19 41.3% 27 58.7% Caucasian 48 5 10.4% 43 89.6%
[0159] [0159] TABLE 11 GROUP I GENOTYPE FREQUENCIES A/A A/C C/C CONTROLS Black men (n = 23) 10 (43%) 10 (43%) 3 (13%) Black women (n = 20) 11 (55%) 8 (40%) 1 (5%) White men (n = 21) 18 (86%) 2 (10%) 1 (5%) White women (n = 24) 19 (79%) 4 (17%) 1 (4%) DISEASE Breast Cancer Black women (n = 8) 3 (38%) 1 (13%) 4 (50%) White women (n = 6) 4 (67%) 1 (17%) 1 (17%) Lung Cancer Black men (n = 10) 5 (50%) 3 (30%) 2 (20%) Black women (n = 8) 4 (50%) 3 (38%) 1 (13%) White men (n = 10) 5 (50%) 3 (30%) 2 (20%) White women (n = 6) 2 (33%) 4 (67%) 0 (0%) Prostate Cancer Black men (n = 8) 5 (63%) 3 (38%) 0 (0%) White men (n = 9) 3 (33%) 5 (56%) 1 (11%) HTN Black men (n = 9) 5 (56%) 2 (22%) 2 (22%) Black women (n = 8) 5 (63%) 3 (38%) 0 (0%) White men (n = 11) 10 (91%) 1 (9%) 0 (0%) White women (n = 9) 7 (78%) 1 (11%) 1 (11%) ESRD due to HTN Black men (n = 6) 4 (67%) 2 (33%) 0 (0%) Black women (n = 5) 3 (60%) 0 (0%) 2 (40%) White men (n = 7) 5 (71%) 2 (29%) 0 (0%) White women (n = 2) 2 (100%) 0 (0%) 0 (0%) NIDDM Black men (n = 8) 5 (63%) 3 (38%) 0 (0%) Black women (n = 8) 4 (50%) 3 (38%) 1 (13%) White men (n = 11) 7 (64%) 2 (18%) 2 (18%) White women (n = 10) 6 (60%) 3 (30%) 1 (10%) ESRD due to NIDDM Black men (n = 2) 1 (50%) 1 (50%) 0 (0%) Black women (n = 9) 5 (56%) 4 (44%) 0 (0%) White men (n = 8) 6 (75%) 2 (25%) 0 (0%) White women (n = 5) 5 (100%) 0 (0%) 0 (0%)
[0160] [0160] TABLE 12 GROUP II GENOTYPE FREQUENCIES Disease Race People N C/C N C/A N A/A Controls African-American 45 4 8.9% 17 37.8% 24 53.3% Caucasian 45 3 6.7% 9 20.0% 33 73.3% Colon cancer African-American 24 0 0.0% 8 33.3% 16 66.7% Caucasian 22 1 4.5% 5 22.7% 16 72.7% Hypertension African-American 21 0 0.0% 6 28.6% 15 71.4% Caucasian 22 0 0.0% 4 18.2% 18 81.8% ASPVD due to HTN African-American 25 2 8.0% 6 24.0% 17 68.0% Caucasian 25 1 4.0% 5 20.0% 19 76.0% CVA due to HTN Caucasian 24 1 4.2% 7 29.2% 16 66.7% Cataracts due to HTN African-American 22 1 4.5% 7 31.8% 14 63.6% ESRD due to HTN African-American 22 4 18.2% 8 36.4% 10 45.5% Caucasian 24 1 4.2% 10 41.7% 13 54.2% HTN CM African-American 24 2 8.3% 3 12.5% 19 79.2% Caucasian 22 0 0.0% 5 22.7% 17 77.3% MI due to HTN African-American 21 2 9.5% 7 33.3% 12 57.1% Caucasian 23 2 8.7% 7 30.4% 14 60.9% NIDDM African-American 22 2 9.1% 7 31.8% 13 59.1% Caucasian 24 5 20.8% 3 12.5% 16 66.7% ASPVD due to NIDDM African-American 23 2 8.7% 11 47.8% 10 43.5% Caucasian 23 1 4.3% 6 26.1% 16 69.6% CVA due to NIDDM African-American 24 0 0.0% 9 37.5% 15 62.5% Caucasian 23 0 0.0% 5 21.7% 18 78.3% Ischemic CM African-American 24 2 8.3% 7 29.2% 15 62.5% Caucasian 21 1 4.8% 6 28.6% 14 66.7% Ischemic CM with NIDDM African-American 24 3 12.5% 8 33.3% 13 54.2% Caucasian 24 0 0.0% 7 29.2% 17 70.8% MI due to NIDDM African-American 24 0 0.0% 6 25.0% 18 75.0% Caucasian 23 0 0.0% 10 43.5% 13 56.5% Afib without valvular disease African-American 24 1 4.2% 12 50.0% 11 45.8% Caucasian 24 0 0.0% 8 33.3% 16 66.7% Alcohol abuse African-American 24 5 20.8% 7 29.2% 12 50.0% Caucasian 24 2 8.3% 8 33.3% 14 58.3% Anxiety African-American 24 3 12.5% 10 41.7% 11 45.8% Caucasian 21 0 0.0% 10 47.6% 11 52.4% Asthma African-American 24 2 8.3% 7 29.2% 15 62.5% Caucasian 24 0 0.0% 6 25.0% 18 75.0% COPD African-American 22 0 0.0% 3 13.6% 19 86.4% Caucasian 21 1 4.8% 6 28.6% 14 66.7% Cholecystectomy African-American 24 1 4.2% 12 50.0% 11 45.8% Caucasian 23 0 0.0% 7 30.4% 16 69.6% DJD African-American 20 1 5.0% 7 35.0% 12 60.0% ESRD and frequent de-clots African-American 23 3 13.0% 7 30.4% 13 56.5% Caucasian 21 1 4.8% 3 14.3% 17 81.0% ESRD due to FSGS African-American 22 1 4.5% 11 50.0% 10 45.5% Caucasian 23 0 0.0% 10 43.5% 13 56.5% ESRD due to IDDM African-American 24 3 12.5% 8 33.3% 13 54.2% Caucasian 22 0 0.0% 3 13.6% 19 86.4% Seizure disorder African-American 23 4 17.4% 11 47.8% 8 34.8% Caucasian 24 0 0.0% 5 20.8% 19 79.2%
[0161] Allele-Specific Odds Ratios
[0162] The susceptibility allele is indicated below, as well as the odds ratio (OR). Where there was a “0” in a cell which produced a 0 in the denominator, Haldane's correction (multiplying all cells by 2 and adding 1) was used. If the odds ratio (OR) was ≧1.5, the 95% confidence interval (C.I.) is also given. An odds ratio of 1.5 was chosen as the threshold of significance based on the recommendation of Austin et al. in Epideyniol. Rev., 16:65-76, 1994. “[E]pidemiology in general and case-control studies in particular are not well suited for detecting weak associations (odds ratios <1.5).” Id. at 66. Odds ratios of greater than 1.5 are highlighted below.
TABLE 13 GROUP I ALLELE-SPECIFIC ODDS RATIOS SUSCEPTIBILITY DISEASE ALLELE OR 95% C.I. Breast Cancer Black women C 3.9 1.1-13 White women C 2.3 0.5-11 Lung Cancer Black men C 1.0 0.3-3.0 Black women C 1.4 0.4-4.9 White men C 5.1 1.3-20 White women C 3.5 0.8-15 Prostate Cancer Black men A 2.3 0.6-9.3 White men C 6.0 1.5-25 Hypertension (HTN) Black men A 1.1 0.3-3.4 Black women A 1.4 0.3-6.1 White men A 2.2 0.2-21 White women C 1.4 0.3-6.3 ESRD due to HTN* Black men A 2.5 0.4-15.2 Black women C 2.9 0.5-17.2 White men C 3.5 0.3-42.8 White women A 2.0 H 0.2-18.8 NIDDM Black men A 2.3 0.6-9.3 Black women C 1.4 White men C 3.6 0.9-14.4 White women C 2.3 0.6-8.8 ESRD due to NIDDM* 1 Black men C 1.4 Black women A 1.6 0.3-7.4 White men A 2.6 0.5-15.2 White women A 7.5 H 0.9-62.1
[0163] [0163] TABLE 14 GROUP II ALLELE-SPECIFIC ODDS RATIOS Lower Upper Risk Odds Limit Limit Disease Race Allele Ratio 95% CI 95% CI Haldane Colon cancer African-American A 1.9 0.8 4.7 Caucasian A 1.1 0.4 2.8 ASPVD due to HTN* African-American C 1.5 0.5 4.5 Caucasian C 1.6 0.4 6.0 CVA due to HTN* Caucasian C 2.3 0.7 8.1 Cataracts due to HTN* African-American A 1.5 0.6 3.6 HTN CM* 1 African-American A 2.1 0.7 6.0 Caucasian A 2.5 0.8 7.8 MI due to HTN* African-American C 2.1 0.7 6.4 Caucasian C 3.1 0.9 10.8 ASPVD due to NIDDM* 2 African-American C 1.5 0.6 3.6 Caucasian A 1.8 0.7 4.8 CVA due to NIDDM* 2 African-American A 1.4 0.5 3.9 Caucasian A 3.0 1.0 9.4 Ischemic CM with NIDDM* 3 African-American C 2.9 1.0 8.3 Caucasian A 1.6 0.6 4.7 MI due to NIDDM* 2 African-American A 2.3 0.8 7.0 Caucasian A 1.3 0.5 3.4 Afib without African-American C 1.1 0.5 2.3 valvular disease Caucasian A 1.0 0.4 2.6 Alcohol abuse African-American C 1.4 0.7 3.0 Caucasian C 1.7 0.7 3.9 Anxiety African-American C 1.3 0.6 2.8 Caucasian C 1.6 0.6 3.8 Asthma African-American A 1.3 0.6 2.9 Caucasian A 1.4 0.5 3.9 COPD African-American A 5.3 1.5 18.5 Caucasian C 1.2 0.5 3.0 Cholecystectomy African-American C 1.1 0.5 2.3 Caucasian A 1.1 0.4 3.0 DJD African-American A 1.3 0.6 3.2 ESRD and frequent African-American C 1.0 0.5 2.3 de-clots Caucasian A 1.5 0.5 4.4 ESRD due to FSGS African-American C 1.1 0.5 2.4 Caucasian C 1.4 0.6 3.4 ESRD due to IDDM African-American C 1.1 0.5 2.3 Caucasian A 2.7 0.7 10.0 Seizure disorder African-American C 1.8 0.9 3.9 Caucasian A 1.7 0.6 5.1
[0164] Genotype-Specific Odds Ratios
[0165] The susceptibility allele (S) is indicated; the alternative allele at this locus is defined as the protective allele (P). Also presented is the odds ratio (OR) for each genotype (SS, SP). The odds ratio for the PP genotype is 1, since it is the reference group, and is not presented separately. For odds ratios ≧1.5, the 95% confidence interval (C.I.) is also given, in parentheses. An odds ratio of 1.5 was chosen as the threshold of significance based on the recommendation of Austin et al., in Epideniiol. Rev., 16:65-76, 1994. “[Epidemiology in general and case-control studies in particular are not well suited for detecting weak associations (odds ratios <1.5).” Id. at 66.
[0166] Haldane's zero cell correction was used when the denominator contained a zero. Odds ratios of greater than 1.5 are highlighted below.
TABLE 15 GROUP I GENOTYPE-SPECIFIC ODDS RATIOS SUSCEPTI- BILITY DISEASE ALLELE OR(SS) OR(SP) Breast Cancer Black women C 14.7 (1.2-185) 0.5 (0-5.3) White women C 4.8 (0.2-93) 1.2 (0.1-14) Lung Cancer White men C 7.2 (0.5-97) 5.4 (0.7-42) White women C 0 9.5 (1.3-71.0) Prostate Cancer Black men A 3.7 (0.4-34) H 2.3 (0.2-22) H White men C 6.0 (0.3-124) 15.0 (1.9-116) Hypertension White men A 1.7 (0.2-17) H 1.8 (0.1-26) H ESRD due to HTN* Black men A 4.1 (0.4-42) H 5.0 (0.4-60) H Black women C 7.9 (0.8-82) H 0 White men C 1.9 (0.1-34) H 4.0 (0.3-55.5) H White women A 1.0 H 1.0 H NIDDM Black men A 3. 7 (0.4-34) H 2.3 (0.2-22) H White men C 5.1 (0.4-66) 2.6 (0.3-22) White women C 3.2 (0.2-59) 2.4 (0.4-14) ESRD due to NIDDM* 1 Black women A 3.7 (0.3-42) H 3.9 (0.3-46) H White men A 4.3 (0.4-42) H 5.0 (0.4-60) H White women A 2.5 (0.2-28) H 0.4 (0-9.4) H
[0167] [0167] TABLE 16 GROUP II GENOTYPE-SPECIFIC ODDS RATIOS RISK SS SP Disease Race ALLELE O.R. HALDANE O.R. HALDANE Colon cancer African-American A 0.0 0.7 Caucasian A 0.7 1.1 ASPVD due to HTN* African-American C 4.4 H 0.9 Caucasian C 2.8 H 1.2 CVA due to HTN* Caucasian C 3.4 H 2.0 Cataracts due to HTN* African-American A 0.4 0.7 HTN CM* 1 African-American A 0.6 0.3 Caucasian A 0.0 0.6 MI due to HTN* African-American C 6.2 H 1.5 Caucasian C 6.4 H 2.3 ASPVD due to African-American C 1.3 2.0 NIDDM* 2 Caucasian A 0.2 2.0 CVA due to NIDDM* 2 African-American A 0.0 1.1 Caucasian A 0.0 1.5 Ischemic CM with African-American C 9.6 H 1.8 NIDDM* 3 Caucasian A 0.8 H 0.5 MI due to NIDDM* 2 African-American A 0.0 0.6 Caucasian A 0.0 4.1 Afib without valvular African-American C 0.5 1.5 disease Caucasian A 0.0 1.8 Alcohol abuse African-American C 2.5 0.8 Caucasian C 1.6 2.1 Anxiety African-American C 1.6 1.3 Caucasian C 0.0 3.3 Asthma African-American A 0.8 0.7 Caucasian A 0.0 1.2 COPD African-American A 0.0 0.2 Caucasian C 0.8 1.6 Cholecystectomy African-American C 0.5 1.5 Caucasian A 0.0 1.6 DJD African-American A 0.5 0.8 ESRD and frequent African-American C 1.4 0.8 de-clots Caucasian A 0.6 0.6 ESRD due to FSGS African-American C 0.6 1.6 Caucasian C 0.0 2.8 ESRD due to IDDM African-American C 1.4 0.9 Caucasian A 0.0 0.6 Seizure disorder African-American C 3.0 1.9 Caucasian A 0.0 1.0
[0168] PCR and sequencing were conducted as described in Example 1. The primers used were those in Example 1. The control samples were in good agreement with Hardy-Weinberg equilibrium, as follows:
[0169] For the Group I diseases, a frequency of 0.65 for the A allele (“p”) and 0.35 for the C allele (“q”) among black male control individuals predicts genotype frequencies of 42% A/A, 46% A/C, and 12% C/C at Hardy-Weinberg equilibrium (p2+2pq+q2=1). The observed genotype frequencies were 43% A/A, 43% A/C, and 13% C/C, in close agreement with those predicted for Hardy-Weinberg equilibrium.
[0170] A frequency of 0.75 for the A allele (“p”) and 0.25 for the C allele (“q”) among black female control individuals predicts genotype frequencies of 56% A/A, 38% A/C, and 6% C/C at Hardy-Weinberg equilibrium (p2+2pq+q2=1). The observed genotype frequencies were 55% A/A, 40% A/C, and 5% C/C, in very close agreement with those predicted for Hardy-Weinberg equilibrium.
[0171] A frequency of 0.90 for the A allele (“p”) and 0.10 for the C allele (“q”) among white male control individuals predicts genotype frequencies of 81% A/A, 18% A/C, and 1% C/C at Hardy-Weinberg equilibrium (p2+2pq+q2=1). The observed genotype frequencies were 86% A/A, 10% A/C, and 5% C/C, in reasonably close agreement with those predicted for Hardy-Weinberg equilibrium.
[0172] A frequency of 0.88 for the A allele (“p”) and 0.13 for the C allele (“q”) among white female control individuals predicts genotype frequencies of 77% A/A, 21% A/C, and 2% C/C at Hardy-Weinberg equilibrium (p2+2pq+q2=1). The observed genotype frequencies were 79% A/A, 17% A/C, and 4% C/C, in reasonably close agreement with those predicted for Hardy-Weinberg equilibrium.
[0173] For the Group II diseases, a frequency of 0.28 for the C allele (“p”) and 0.72 for the A allele (“q”) among African-American control individuals predicts genotype frequencies of 8.0% C/C, 40.0% C/A, and 52.0% A/A at Hardy-Weinberg equilibrium (p 2 +2pq+q 2 =1). The observed genotype frequencies were 8.9% C/C, 37.8% C/A, and 53.3% A/A, in excellent agreement with those predicted for Hardy-Weinberg equilibrium.
[0174] A frequency of 0.17 for the C allele (“i”) and 0.83 for the A allele (“q”) among Caucasian control individuals predicts genotype frequencies of 3.0% C/C, 28.0% C/A, and 69.0% A/A at Hardy-Weinberg equilibrium (p 2 +2pq+q 2 =1). The observed genotype frequencies were 6.7% C/C, 20.0% C/A, and 73.3% A/A, in excellent agreement with those predicted for Hardy-Weinberg equilibrium.
[0175] Using an allele-specific odds ratio of 1.5 or greater as a practical level of significance (see Austin H et al., discussed above), the following observations can be made.
[0176] For breast cancer among black women, the odds ratio for the C allele as a risk factor was 3.9 (95% CI, 1.1-13). The odds ratio for the homozygote (CC) was a remarkable 14.7 (95% CI, 1.2-185). The heterozygote (CA genotype) had an odds ratio indistinguishable from 1 (odds ratio 0.5; 95% C.I. 0-5.3), suggesting that the C allele behaves as a recessive allele in this patient population.
[0177] For breast cancer among white women the odds ratio for the C allele as a risk factor was 2.3 (95% CI, 0.5-11). The odds ratio for the homozygote (CC genotype) was 4.8 (95% CI, 0.2-93). The heterozygote (CA genotype) had an odds ratio indistinguishable from 1 (odds ratio 1.2; 95% C.I. 0.1-14), suggesting that the C allele behaves as a recessive allele in this patient population.
[0178] For lung cancer in white men the odds ratio for the C allele as a risk factor was 5.1 (95% CI, 1.3-20). The C allele displayed a dosage effect, with the heterozygote (AC) having an odds ratio of 5.4 (95% CI, 0.7-42), and the homozygote (CC) an odds ratio of 7.2 (95% CI, 0.5-97). These data are consistent with a dominant action of the C allele, since one copy is sufficient to increase the odds ratio from 1 (for the AA homozygote) to 5.4 (for the AC heterozygote). The increase to 7.2 represents less than an additive effect of the allele, since 5.4+5.4−1=9.8>7.2. These data are consistent with the C allele behaving as a dominant allele with interaction on less than an additive model.
[0179] For lung cancer in white women the odds ratio for the C allele (the novel SNP) as a risk factor was 3.5 (95% CI, 0.8-15). The CC homozygote surprisingly had a lower odds ratio, 0, than the heterozygote [9.5; 95% C.I., 1.3-71.0], suggesting that the C allele behaves other than as a simple recessive or dominant allele. The C allele may be codominant with the A allele.
[0180] For prostate cancer among black men the odds ratio for the reference A allele as a risk factor was 2.3 (95% CI, 0.6-9.3). The odds ratio for the homozygote (AA genotype) was 3.7 H (95% CI, 0.4-34). The heterozygote (AC genotype) had an odds ratio of 2.3 H (95% CI, 0.2-22). The A allele therefore behaves as a dominant allele, with an additive effect of increased allele dosage. The effect of the A allele on disease is as expected for an additive model (3.7˜2.3+2.3−1).
[0181] For prostate cancer in white men the odds ratio for the C allele (the novel SNP) as a risk factor was 6.0 (95% CI, 1.5-25). The CC homozygote surprisingly had a lower odds ratio (6.0; 95% CI, 0.3-124) than the heterozygote (15.0; 95% C.I. 1.9-116), suggesting that the C allele behaves other than as a simple dominant or recessive r lele. The C allele may be codominant with the A allele.
[0182] For hypertension among white men the odds ratio for the reference A allele as a risk factor was 2.2 (95% CI, 0.2-21). The odds ratio for the homozygote (AA genotype) was virtually the same (1.7 H ; 95% CI,, 0.2-17) as that for the AC heterozygote (1.8 H ; 95% CI, 0.1-26). These data indicate that the A allele behaves as a simple dominant allele, with no additional effect of a second copy of the allele.
[0183] For ESRD due to hypertension among black men the odds ratio for the reference A allele as a risk factor was 2.5 (95% CI, 0.4-15.2). The odds ratio for the homozygote (AA genotype) was 4.1 H (95% CI, 0.4-42), and that for the AC heterozygote was essentially the same [5.0 H (95% CI, 0.4-60)). These data suggest that the A allele behaves as a dominant allele.
[0184] For ESRD due to hypertension among black women the odds ratio for the C allele as a risk factor was 2.9 (95% CI, 0.5-17.2). The heterozygote (AC) had an odds ratio of 0, whereas the CC homozygote displayed an odds ratio of 7.9 H (95% CI, 0.8-82). These data are consistent with a recessive action of the C allele.
[0185] For ESRD due to hypertension among white men the odds ratio for the A allele as a risk factor was 3.5 (95% CI, 0.3-42.8). The odds ratio for the AC heterozygous genotype was 4.0 (95% CI, 0.3-55.5), and for the AA homozygous genotype was 1.9 H (95% CI, 0.1-34). The A allele appears to be codominant with the C allele.
[0186] For ESRD due to hypertension among white women the odds ratio for the A allele was 2.0 H (95% CI, 0.2-18.8), relative to white women with hypertension but no renal disease. The odds ratios for both the AC heterozygote and the AA homozygote were only 1.0 after the Haldane's correction, shedding no light on the mechanism of action of the A allele.
[0187] For NIDDM among black men, the odds ratio for the A allele at this locus was 2.3 (95% CI, 0.6-9.3). The odds ratio for the heterozygote was 2.3 H (95% CI, 0.2-22), and for the AA homozygote was 3.7 H (95% CI, 0.4-34). These data suggest that the A allele behaves as a dominant allele, with an additive effect of allele dosage (2.3+2.3−1˜3.7).
[0188] For NIDDM among white men, the odds ratio for the C allele at this locus was 3.6 (95% CI, 0.9-14.4). The odds ratio for the heterozygote was 2.6 (95% CI, 0.3-22), and for the CC homozygote was 5.1 (95% CI, 0.4-66). These data suggest that the C allele behaves as a dominant allele, with more than an additive effect of allele dosage (2.6+2.6−1<5.1).
[0189] For NIDDM among white women, the odds ratio for the C allele at this locus was 2.3 (95% CI, 0.6-8.8). The odds ratio for the heterozygote was 2.4 (95% CI, 0.4-14), and for the CC homozygote was 3.2 (95% CI, 0.2-59). These data suggest that the C allele behaves as a dominant allele, with approximately an additive effect of allele dosage (2.4+2.4−1=3.8˜3.2).
[0190] For ESRD due to NIDDM among black women, the odds ratio for the A allele at this locus was 1.6 (95% CI, 0.3-7.4). The odds ratio for the heterozygote was 3.9 H (95% CI, 0.3-46), and for the AA homozygote was 3.7 H (95% CI, 0.3-42). These data suggest that the A allele behaves as a classic dominant allele, with no effect of allele dosage.
[0191] For ESRD due to NIDDM among white men, the odds ratio for the A allele at this locus was 2.6 (95% CI, 0.5-15.2). The odds ratio for the heterozygote was 5.0 H (95% CI, 0.4-60), and for the AA homozygote was 4.3 H (95% CI, 0.4-42). These data suggest that the A allele behaves as a classic dominant allele, with no effect of allele dosage.
[0192] For ESRD due to NIDDM among white women, the odds ratio for the A allele at this locus was 7.5 (95% CI, 0.9-62.1). The odds ratio for the heterozygote was indistinguishable from 1, and for the AA homozygote was 2.5 H (95% CI, 0.2-28). These data suggest that the A allele behaves as a recessive allele.
[0193] For Caucasians with a history of alcohol abuse the odds ratio for the C allele was 1.7 (95% CI, 0.7-3.9). The odds ratio for the homozygote (C/C) was 1.6 (95% CI, 0.2-10.5), while the odds ratio for the heterozygote (C/ A) was 2.1 (95% CI, 0.7-6.5). These data suggest that the C allele acts in a co-dominant manner in this patient population. These data further suggest that the EDN-1 gene is significantly associated with alcohol abuse in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to alcohol abuse.
[0194] For Caucasians with anxiety the odds ratio for the C allele was 1.6 (95% CI, 0.6-3.8). The odds ratio for the homozygote (C/C) was 0, while the odds ratio for the heterozygote (C/A) was 3.3 (95% CI, 1.1-10.3). These data suggest that the C allele acts in a co-dominant manner in this patient population. These data further suggest that the EDN-1 gene is significantly associated with anxiety in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to anxiety.
[0195] For Caucasians with ASPVD due to NIDDM the odds ratio for the A allele was 1.8 (95% CI, 0.7-4.8), compared to Caucasians with NIDDM only. The odds ratio for the homozygote (A/A) was 0.2 (95% CI, 0-1.9), while the odds ratio for the heterozygote (C/A) was 2.0 (95% CI, 0.4-9.4). These data suggest that the A allele acts in a co-dominant manner in this patient population. These data further suggest that the EDN-1 gene is significantly associated with ASPVD due to NIDDM in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to ASPVD due to NIDDM.
[0196] For African-Americans with colon cancer the odds ratio for the A allele was 1.9 (95% CI, 0.8-4.7). Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with colon cancer in African-Americans, i.e. abnormal activity of the EDN-1 gene predisposes African-Americans to colon cancer.
[0197] For African-Americans with COPD the odds ratio for the A allele was 5.3 (95% CI, 1.5-18.5). Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with COPD in African-Americans, i.e. abnormal activity of the EDN-1 gene predisposes African-Americans to COPD.
[0198] For African-Americans with diabetic cardiomyopathy the odds ratio for the C allele was 2.9 (95% CI, 1-8.3), compared to African-Americans with MI due to NIDDM. The odds ratio for the homozygote (C/C) was 9.6 H (95% CI, 0.2-574.5), while the odds ratio for the heterozygote (C/A) was 1.8 (95% CI, 0.5-6.6).These data suggest that the C allele acts in a dominant manner in this patient population. These data further suggest that the EDN-1 gene is significantly associated with diabetic cardiomyopathy in African-Americans, i.e. abnormal activity of the EDN-1 gene predisposes African-Americans to diabetic cardiomyopathy.
[0199] For Caucasians with diabetic cardiomyopathy the odds ratio for the A allele was 1.6 (95% CI, 0.6-4.7), compared to Caucasians with MI due to NIDDM. Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with diabetic cardiomyopathy in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to diabetic cardiomyopathy.
[0200] For Caucasians with ESRD due to IDDM the odds ratio for the A allele was 2.7 (95% CI, 0.7-10). Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with ESRD due to IDDM in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to ESRD due to IDDM.
[0201] For African-Americans with ESRD due to IDDM the odds ratio for the C allele was 1.6 (95% CI, 0.6-3.9), compared to African-Americans with NIDDM only. The odds ratio for the homozygote (C/C) was 2.0 (95% CI, 0.3-14), while the odds ratio for the heterozygote (C/A) was 1.7 (95% CI, 0.5-6.1). These data suggest that the C allele acts in a dominant manner in this patient population with a less than additive effect of allele dosage [2<3.4=(1.7+1.7−1.0)]. (Goldstein et al., Monogr. Natl. Cancer Inst.; 26:49-54, 1999). These data further suggest that the EDN-1 gene is significantly associated with ESRD due to IDDM in African-Americans, i.e. abnormal activity of the EDN-1 gene predisposes African-Americans to ESRD due to IDDM.
[0202] For African-Americans with hypertensive cardiomyopathy the odds ratio for the A allele was 2.1 (95% CI, 0.7-6.0), compared to African-Americans with MI due to HTN. Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data firer suggest that the EDN-1 gene is significantly associated with hypertensive cardiomyopathy in African-Americans, i.e. abnormal activity of the EDN-1 gene predisposes African-Americans to hypertensive cardiomyopathy.
[0203] For Caucasians with hypertensive cardiomyopathy the odds ratio for the A allele was 2.5 (95% CI, 0.8-7.8), compared to Caucasians with MI due to HTN. Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with hypertensive cardiomyopathy in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to hypertensive cardiomyopathy.
[0204] For Caucasians with CVA due to NIDDM the odds ratio for the A allele was 3.0 (95% CI, 1-9.4), compared to Caucasians with NIDDM only. The odds ratio for the homozygote (A/A) was 0, while the odds ratio for the heterozygote (C/A) was 1.5 (95% CI, 0.3-7.2).These data suggest that the A allele acts in a manner in this patient population. These data further suggest that the EDN-1 gene is significantly associated with CVA due to NIDDM in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to CVA due to NIDDM.
[0205] For African-Americans with MI due to NIDDM the odds ratio for the A allele was 2.3 (95% CI, 0.8-7), compared to African-Americans with NIDDM only. Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with MI due to NIDDM in African-Americans, i.e. abnormal activity of the EDN-1 gene predisposes African-Americans to MI due to NIDDM.
[0206] For African-Americans with seizure disorder the odds ratio for the C allele was 1.8 (95% CI, 0.9-3.9). The odds ratio for the homozygote (C/C) was 3.0 (95% CI, 0.6-14.9), while the odds ratio for the heterozygote (C/A) was 1.9 (95% CI, 0.6-5.8).These data suggest that the C allele acts in a dominant manner in this patient population with a greater than additive effect of allele dosage [3>3.8=(1.9+1.9−1.0)]. (Goldstein et al., Monogr. Natl. Cancer Inst.; 26:49-54, 1999). These data further suggest that the EDN-1 gene is significantly associated with seizure disorder in African-Americans, i.e. abnormal activity of the EDN-1 gene predisposes African-Americans to seizure disorder.
[0207] For Caucasians with seizure disorder the odds ratio for the A allele was 1.7 (95% CI, 0.6-5.1). Data were not sufficient to generate genotypic odds ratios of 1.5 or greater. These data further suggest that the EDN-1 gene is significantly associated with seizure disorder in Caucasians, i.e. abnormal activity of the EDN-1 gene predisposes Caucasians to seizure disorder.
[0208] According to MatInspector (GENOMATIX; see above for URL and reference), the C2657→A SNP disrupts a binding site for CEBPB (CCAAT/enhancer binding protein-beta; Quandt K et al., Nucleic Acids Res., 23: 4878-4884 (1995)). CEBPB binds to a core sequence of four nucleotides, GMAA, in an overall sequence of 14 nucleotides (ref. Akira, S. et al. A nuclear factor for IL-6 expression (NF-IL6) is a member of a C/EBP family. EMBO J. 1990 Jun:9(6):1897-1906). CEBPB — 01 binding sites, which occur on average 2.07 times per 1000 base pairs of random genomic sequence in vertebrates, are predicted to occur at positions 2647 to 2660 on the (+) strand of reference sequence J05008.1 (matrix score 0.952, with 1.0 being an identical match), as well as from position 2670 to 2657 on the (−) strand (matrix score 0.891 out of a possible 1.0). In neither case, however, does the C2657→A SNP alter a nucleotide critical for binding.
TABLE 17 Reference Gene Region Location Type Variant SEQ ID EDN-1 Promoter 2239 T G 1 2657 A C 1
CONCLUSION
[0209] In light of the detailed description of the invention and the examples presented above, it can be appreciated that the several aspects of the invention are achieved.
[0210] It is to be understood that the present invention has been described in detail by way of illustration and example in order to acquaint others skilled in the art with the invention, its principles, and its practical application. Particular formulations and processes of the present invention are not limited to the descriptions of the specific embodiments presented, but rather the descriptions and examples should be viewed in terms of the claims that follow and their equivalents. While some of the examples and descriptions above include some conclusions about the way the invention may function, the inventor does not intend to be bound by those conclusions and fictions, but puts them forth only as possible explanations.
[0211] It is to be further understood that the specific embodiments of the present invention as set forth are not intended as~being exhaustive or limiting of the invention, and that many alternatives, modifications, and variations will be apparent to those of ordinary skill in the art in light of the foregoing examples and detailed description. Accordingly, this invention is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and scope of the following claims.
1
5
1
12459
DNA
Homo sapiens
repeat_region
(98)..(383)
1
gatatcctat taatacagag atacagaaag aaatacataa aaaatagttt tatcaaatac 60
tttccagcat tcaagtgtag cctcaaaagc aagaataggc caggagtggt ggctcacgct 120
gtaatccaca gcactgtggg aggccaaggt aagaggattg cttgaggcca ggatttcaag 180
accagcctag gcaacatagt gagatcccta tctctacgaa aaaattttaa aacttagctg 240
ggcatggtgc ttgagcctgt tgtcccagct actcaggagg tgaagtagga gtgtcacttg 300
agcccaggag gttgaggctg cagtgagcta taactgcacc actgcactcc agccttggag 360
acagagtgag accctgtccc caaaaaaatt aaaattgaga aaaaaaaaaa ggcaagaaca 420
gccacagcaa actttctatt ggggaaaaaa aaaaatcctc ctctttacat ctctcccttc 480
cttcccttcc ctttctgaga gtgactgtgg ccaaaaggag cattttcccc ctgcagtcct 540
ctgaggggtg gggtggggct atgaagctat ccttcatatt cactcctttg tccagctctt 600
ttcacctcta gttcttctcc ccgcatctct gtctagcagt gccttaagtg gaggaggggt 660
gggggcatca agcttgtaaa actggtttgt tggggttctc cttctcccct catttcttga 720
ttcttgggaa aatgtcttgc tgggaggctg cctggcgagt gccctagctg ccttctgtgg 780
gcttgaatgg ggcttccctc tgcccctaca ggaggaaaag ggagctgctg ccagagggag 840
aaatggagag atggacagag aaggcaggtg ccacccctcg cccctgacac acaaagaaaa 900
agacacggaa attctctctc tctcttctct tctcctatct ctctctctct ccctctctct 960
ctctctctct ctctctctca cacacacaca cacacacaca cacacacaca caggcgcgcg 1020
ccgcgcgcgc aggcacacgt cttgcaaatt caggattcaa agagacaggg gcaccattat 1080
atttggcacg gtggggcctt ccaggtctga aatcctgcat tcttccttac tatttacttt 1140
ccccgagctc gagaagggcc aggtgtgggc ggatggctgg ccacgttttg tgtttccaat 1200
tcatattcac gggatgacac agacggggcg tggtgagtgc tgttggaggc gcttgggcag 1260
tttcattttg ccccacttct ccacctgaag gctgggcgtt gctggaacct gcaggggcag 1320
cctcagcaag gtggggtggc gtggagtggg gtgggagaag ggactccagc tgaagtagaa 1380
cccaggctgg acctgagaat attggggagg gcatgggcgg tggtttccgg gtaggggcct 1440
tgaggacatg ttggtcctga ctgttgtcag tgtttggtca aagttgccaa aaggttaaaa 1500
aaaaaaaagt agggggagtc cctgccaaga catatttccc aggccacctt tcttccgcgg 1560
gagtgttggg ggggaggcgc tgcttggaac ctgtgaatgt gacatcagct ctcctctcct 1620
ctcccaaggt cggctttgga gagggaggtc agggcaccct tgcctggcac aggcacgctg 1680
gcttccggct cagtgccgcc tgctctccgg gagctgtgcg ctccctgggc cccggggcta 1740
ggctgaggta agcgcacagc ggaggccagg cgcgccggca gaggcctggg ggatagggtg 1800
gaggcatctc tgggtgtggg tgtgggtgtg ggtgtgggag ggagagttct tgcctctctc 1860
tctcccatct ccaactcttg cttcagtggc tcttttagag gatgcatgtc attatggacc 1920
tgtcgctgcc actgtccctg ttcccccagc tgtgacttcg agggaggtct ggggatctga 1980
gtctgtccaa acccacggct ttgctgttgg gataaaaact gtccttttga ttttagaagg 2040
aggagggaaa aaaggtttcc cagcatgtgt gttgtgccag tcttggaaat tcatccgtgc 2100
ttgaattcca ccctccatcc ccagaaaaac tggagtaaaa caaaaagagg agatggacaa 2160
agtgtgtatt tgatggcatc ccctgggaag agactctaaa tttatcccat aggtcttact 2220
gggccactgt gagcgctttg gtggagaaca aacaaaaatt ctgggtgctc agttgtctaa 2280
cctgaaaaat gggactagcg gaaaaagcca atgtgttcca tgcacctttt gctttcttta 2340
ttaaggcatg atgtcacctg tacagtaact gccctgtgtg tacttcaggg ggggatttca 2400
aggttagata gacaggaaat tgttttgaaa atgtaaacac attattaaat gtgaagtatt 2460
atctgattcc ttgttcgaat ggcatttcct tctcagcacc accttccttg catattcact 2520
taaccttgta caagaacacc tttttgccct aaatgaagac acccccccaa aaaaaagagt 2580
cccagaaaat atgtccctgc ttgtgcggga ataaatagaa tattctgagg tgcattcctc 2640
cttcctatgt taggcaacat tccttgaccc tcctcggccc ccaagccagg ttgcgttttt 2700
ttctgccatt tagaagggtt ttcctttttg tcctagtaaa acatcagccc ctgtagctct 2760
tcatctcccc ctggtgttct tctcccgcca tgtcttaaga ttggtggcac cgaccaatct 2820
taagatttaa gttctgtgtg aaaaacacct ttgcttttca atcagtttat cagcctcctc 2880
cgcaggggaa tgtggacaca caaaagaact tatcggggct tctcatcagt gatagggaaa 2940
agactggcat gtgcctaaac gagctctgat gttattttta agctcccttt cttgccaatc 3000
cctcacggat ctttctccga tagatgcaaa gaacttcagc aaaaaagacc cgcaggaagg 3060
ggcttgaaga gaaaagtacg ttgatctgcc aaaatagtct gacccccagt agtgggcagt 3120
gacgagggag agcattccct tgtttgactg agactagaat cggagagaca taaaaggaaa 3180
atgaagcgag caacaattaa aaaaaattcc ccgcacacaa caatacaatc tatttaaact 3240
gtggctcata cttttcatac caatggtatg actttttttc tggagtcccc tcttctgatt 3300
cttgaactcc ggggctggca gcttgcaaag gggaagcgga ctccagcact gcacgggcag 3360
gtttagcaaa ggtctctaat gggtattttc tttttcttag ccctgccccc gaattgtcag 3420
acggcgggcg tctgcttctg aagttagcag tgatttcctt tcgggcctgg cttatctccg 3480
gctgcacgtt gcctgttggt gactaataac acaataacat tgtctggggc tggaataaag 3540
tcggagctgt ttacccccac tctaataggg gttcaatata aaaagccggc agagagctgt 3600
ccaagtc aga cgc gcc tct gca tct gcg cca ggc gaa cgg gtc ctg cgc 3649
Arg Arg Ala Ser Ala Ser Ala Pro Gly Glu Arg Val Leu Arg
1 5 10
ctc ctg cag tcc cag ctc tcc acc gcc gcg tgc gcc tgc aga cgc tcc 3697
Leu Leu Gln Ser Gln Leu Ser Thr Ala Ala Cys Ala Cys Arg Arg Ser
15 20 25 30
gct cgc tgc ctt ctc tcc tgg cag gcg ctg cct ttt ctc ccc gtt aaa 3745
Ala Arg Cys Leu Leu Ser Trp Gln Ala Leu Pro Phe Leu Pro Val Lys
35 40 45
ggg cac ttg ggc tga agg atc gct ttg aga tct gag gaa ccc gca gcg 3793
Gly His Leu Gly Arg Ile Ala Leu Arg Ser Glu Glu Pro Ala Ala
50 55 60
ctt tga ggg acc tga agc tgt ttt tct tcg ttt tcc ttt ggg ttc agt 3841
Leu Gly Thr Ser Cys Phe Ser Ser Phe Ser Phe Gly Phe Ser
65 70 75
ttg aac ggg agg ttt ttg atc cct ttt ttt cag aat gga tta ttt gct 3889
Leu Asn Gly Arg Phe Leu Ile Pro Phe Phe Gln Asn Gly Leu Phe Ala
80 85 90
cat gat ttt ctc tct gct gtt tgt ggc ttg cca agg agc tcc aga aac 3937
His Asp Phe Leu Ser Ala Val Cys Gly Leu Pro Arg Ser Ser Arg Asn
95 100 105
ag gtaggcacgc tcgttgactt gtaagtctcg gaattacaag ttagtgtgtt 3989
Ser
cttatccacc ttcatgcttt tcttgcttct atttttcccc gttcttttta tgactgcagc 4049
ttagagagca agtgtctgag aattattgct gaaacgtact ttaagtcttc tagtgtaaaa 4109
tgtaaaattc ctctactgaa tacaattagg tgcaattgac tataacatga cattaaaata 4169
acttatcgtt ttattattat tattccatta tgtgtttcct tggcttttaa aaaatgagaa 4229
gagtatggac atatacaatt tagtcaaatg tatgtttgta atatatgtgt ttatacaggt 4289
acacaggcca tataggaact taaatcttat ttaaacacta ttttaatagt gtgttaacgt 4349
gtaaaatatt taagcattcc agcttgaagc caaggaattg tatccagtcg ttcaagcaat 4409
gtatgttcag taaaatcacc tgcagagcaa aagtctgttg actaactacc gcctcccccg 4469
cccccccacc accccccgca ggcggtttct gggtgaagca gatgttttct ttaaaatttg 4529
tcatcattga ctttaggttt cttttggcag gtttttggca cccaaaacag tgtgagctct 4589
cttttcagct ttattcacct gtgctgggag gggagctagg ataattcttg gctgccgaag 4649
gatttaggca gtgcgtgtgc atctgcccgg gtcccccccg tttttagggt cagtgcactt 4709
tttttgtctt ttcgtgaccc tgactaaaga gaaaggatgt caagggaatg aaaatcctgg 4769
aatgtgtctg atcatttgaa atgtacaaaa ttgggcagat aagctgcatg gctaaattgt 4829
taggaggaag aggcaaggca gtagtggaga agggggaggc agtggatccc acacaagcct 4889
gatgcccagg gattcggaat tcaaaatccc cccagcctac cttcagtccc ctgacctgct 4949
tctcagcccc accttaggtc actggtttct atggagttac cctactgaat tgaatattga 5009
atagttaatt tctctctcca atcattttcc ccacctaatt ttgaaagata tacatcatct 5069
ggggtaccct gtgccctaca cagcatgtga agtggatggg taccccctaa agagagggtc 5129
atcctgaatg gggaagtggc cccaaagcta ggaataactg tgatttcttg tctttagtca 5189
tgtgccaatg ttaagtaagc ttcagtggat agtgctgtcc taccaagttc cttgtagaag 5249
ccagccggat tttcaacagg cagcattcca cagcatttcc ctgagcctgc ttcaagaggg 5309
gtgggggaag tcccttttca ggtgtttatc tcctctgcat ttgtgtaatc tccctgaagg 5369
tggataagcc aagggcatga gggggaggca aaaggtgaac tcatgttaag gagggaaaaa 5429
aataaagagc ccttttttct gtgtttcttg ctgatggcag gctgtgtgct tcatctgctt 5489
ttatctgctc tgctagctct gactctactg tgatccagca tgtctctcgg cgtttgagga 5549
gacatccccc actgacctgc tctttctctc cccag c agt ctt agg cgc tga gct 5603
Ser Leu Arg Arg Ala
110
cag cgc ggt ggg tga gaa cgg cgg gga gaa acc cac tcc cag tcc acc 5651
Gln Arg Gly Gly Glu Arg Arg Gly Glu Thr His Ser Gln Ser Thr
115 120 125
ctg gcg gct ccg ccg gtc caa gcg ctg ctc ctg ctc gtc cct gat gga 5699
Leu Ala Ala Pro Pro Val Gln Ala Leu Leu Leu Leu Val Pro Asp Gly
130 135 140
taa aga gtg tgt cta ctt ctg cca cct gga cat cat ttg ggt caa cac 5747
Arg Val Cys Leu Leu Leu Pro Pro Gly His His Leu Gly Gln His
145 150 155
tcc cga gtaagtctct agagggcatt gtaaccctat tcattcatta gcgctggctc 5803
Ser Arg
160
cactggagcc cagttttaga gtttcttttc tagggactct gaaggtagtc cttctaacac 5863
catccaagtg cctcagtggg gacagtttcc ctctattcct gaaaataacg acagcttcgt 5923
tcttagcaac caaggggagg gtcttctgag gccccgtagc tcaggctact catgatggga 5983
caagcaggag gccactgcac gtttcaaatg aggaactttc agtgagaggg cctcaggggg 6043
acactctcac agtggcatct gatggggttt cgggaataat tgccgaggtc agatgtgggt 6103
tagtgcaacc tgtgcttctc atgggagggt ggagactgag aggcagaagt gatgatatag 6163
agggttagaa tcacttaatt ttagttacag aaaaacctag gctcaaagtg ttgaagccat 6223
ttgtgcagga gtgagtttgt agcagagcta gaactggagc ccggatttcc tttgctgcta 6283
tattttccct ttagaaatgc ccatttcaga actgaaatag aaatactgtc cataggcttc 6343
tctttcacct acagagaaga aaagcagatt tcctccttct gccctggaca ctagttcatc 6403
atctgtcgga agcagtcata aacaagcaca catttactat gcatacaatg taccgttatg 6463
acaaaggagg accaaaatcc aaacaatatc aaaccacacc aaaaaccaca aggagcctaa 6523
taattactaa ggtgatactt ccaaagggag gactttattt cttagatgag aatgaaaatg 6583
gacacattgg aaattattgg agagccctct ggctatgagt ccttccacaa ccatatggta 6643
ccaccgactg gcaggagaaa tgtgtgaaca tgtgcctcct ctccccaacc actggggccg 6703
gtggggtgac ggtggcactt ttagcagtat cctccgtggt ttgagttgaa aataagtttt 6763
aaaaatcctg tgagtcatgg ttttgcattg aaacctcttc ccactgtgta cccacaaata 6823
gttaactaaa tagaccatta gaaaaggaag aaaatataaa gcagatgcca agcagagatg 6883
tcctaatttt tgacaaaaaa gcaatgttgc ttgtgtcaag aagaaactga actttgtgaa 6943
gagttgaaat ggaattccac tgaattagaa aaacttgttt tctcctgcct ggatacatac 7003
agtcagggcc attgatgcac aggtgttcct ggctgttgtt acactttacc ctctgaaatg 7063
atgctcccaa gtgctatgtg atgagctcct tgtgtgccca gtggaatagg tgtgtccatg 7123
tgtcatttta aagactatta attacactaa tatagtttct ttctctcttt ggataatag 7182
gca cgt tgt tcc gta tgg act tgg aag ccc tag gtc caa gag agc ctt 7230
Ala Arg Cys Ser Val Trp Thr Trp Lys Pro Val Gln Glu Ser Leu
165 170 175
gga gaa ttt act tcc cac aaa ggc aac aga ccg tga gaa tag atg cca 7278
Gly Glu Phe Thr Ser His Lys Gly Asn Arg Pro Glu Met Pro
180 185 190
atg tgc tag cca aaa aga caa gaa gtg ctg gaa ttt ttg cca agc agg 7326
Met Cys Pro Lys Arg Gln Glu Val Leu Glu Phe Leu Pro Ser Arg
195 200 205
aaa aga act cag gtgagcagaa acacctttgc ttttcaatca gtttaacagc 7378
Lys Arg Thr Gln
ctcctgaact ccttcctatc atggtactgc cttcctgttt tagagagact aacagagaca 7438
ttgaaagtca gggtaaagct gaatataaca ttgctgaaat gtttttcctt gtgtatttta 7498
acag ggc tga aga cat tat gga gaa aga ctg gaa taa tca taa gaa agg 7547
Gly Arg His Tyr Gly Glu Arg Leu Glu Ser Glu Arg
210 215 220
aaa aga ctg ttc caa gct tgg gaa aaa gtg tat tta tca gca gtt agt 7595
Lys Arg Leu Phe Gln Ala Trp Glu Lys Val Tyr Leu Ser Ala Val Ser
225 230 235
gag agg aag aaa aat cag aag aag ttc aga gga aca cct aag aca aac 7643
Glu Arg Lys Lys Asn Gln Lys Lys Phe Arg Gly Thr Pro Lys Thr Asn
240 245 250
cag gtaagaggga aggaagaaaa attaggtaag aggttcacaa gaacaactag 7696
Gln
ccccagtcag tgatgccagc agcctgttcc tccagccctt cttacccggg caggtgaaag 7756
acttagaaaa cagtagcaga ggagatctat gcatcctata gattaaaagg agcaaaagaa 7816
tccctcttaa atatttccat gaagctctgg aatgcaaacc gatgtcctct gtacctttag 7876
cacataccat ttcatctaca ggtagatttc ccaaccaaaa tatatccaga gatgcctttg 7936
tcattgggtt atatacagcc tttgcctctc tgagtcaatg tatttaccac tttccctgag 7996
aaatcgaaaa tcattttggg gagcggacat ttagaaaaag aatcaaagtg tcatggataa 8056
tcaaattctt caataagttg cagttattca gatggccaaa ggaaaaataa agtcattaga 8116
tagggttggt agaatttaga acatgctgtt tttcaggttt atggtctttt tttttttttt 8176
tttttttttt taaataggga aatgtgtttg gtgcagagcc aatgtcattc caaaaagctc 8236
tctcttttcc tggtcagtca tgtgctggga cagagaaggg atctggatta ggcaacatca 8296
tagagttgct ctgagctgct ctttggtgat aacccttcca aatcctaaac tttttggaat 8356
tcacaagctc aaaggaggaa acctactctc tgatctacca catgttctgc atttttctat 8416
catggtctat ggaaacttct cttagaaatc cagtggcaag aagttctatg attaaagtgt 8476
tctgagctca ggccaggcag tcatgaacta cttctgagtt gtttactact gatttgtggg 8536
gcagcctcag ctatcggttt cttcacacct gcttatgaga gtatccatat ttatggtcgc 8596
aggcagtaat gctccccacg agatcagttt ctgaactaac ctggaatttt ttatgggttt 8656
ttattatgcc aactattaaa tcaacattac agttcttccc tctgtatttc tcctgtaaaa 8716
cattaggcct gcaaaaaaaa aaaatctttt taaaaataat tgccataaag tatttgctct 8776
gggcctactg tatgcttctt ttytttttct ctcttttcaa ctaagtcacc gtcaatttat 8836
taagatggcc ataactattc aaaacctatg ctgagttcct caaggcaggg tcgcatagtg 8896
atgaaggttg ggatggggct acggaagaaa ccagaacaac tctagtttat ttaaaacctg 8956
tatttactgc ccacttcccc ttagacttga ccatatgacc ccttgctccc cattctaagc 9016
ataggggcag gctttatttt tacaatggta atagatgata tcacttgagg ttttatcaaa 9076
gagttgcggc gggtggtgaa agttcacaac cagattcagg ttttgtttgt gccagattct 9136
aattttacat gtttcttttg ccaaagggtg atttttttaa aataacattt gttttctctt 9196
atcttgcttt attag gtc gga gac cat gag aaa cag cgt caa atc atc ttt 9247
Val Gly Asp His Glu Lys Gln Arg Gln Ile Ile Phe
255 260 265
tca tga tcc caa gct gaa agg caa gcc ctc cag aga gcg tta tgt gac 9295
Ser Ser Gln Ala Glu Arg Gln Ala Leu Gln Arg Ala Leu Cys Asp
270 275 280
cca caa ccg agc aca ttg gtg aca gac ctt cgg ggc ctg tct gaa gcc 9343
Pro Gln Pro Ser Thr Leu Val Thr Asp Leu Arg Gly Leu Ser Glu Ala
285 290 295
ata gcc tcc acg gag agc ctg tgg ccg act ctg cac tct cca ccc tgg 9391
Ile Ala Ser Thr Glu Ser Leu Trp Pro Thr Leu His Ser Pro Pro Trp
300 305 310
ctg gga tca gag cag gag cat cct ctg ctg gtt cct gac tgg caa agg 9439
Leu Gly Ser Glu Gln Glu His Pro Leu Leu Val Pro Asp Trp Gln Arg
315 320 325
acc agc gtc ctc gtt caa aac att cca aga aag gtt aag gag ttc ccc 9487
Thr Ser Val Leu Val Gln Asn Ile Pro Arg Lys Val Lys Glu Phe Pro
330 335 340 345
caa cca tct tca ctg gct tcc atc agt ggt aac tgc ttt ggt ctc ttc 9535
Gln Pro Ser Ser Leu Ala Ser Ile Ser Gly Asn Cys Phe Gly Leu Phe
350 355 360
ttt cat ctg ggg atg aca atg gac ctc tca gca gaa aca cac agt cac 9583
Phe His Leu Gly Met Thr Met Asp Leu Ser Ala Glu Thr His Ser His
365 370 375
att cga att cgg gtg gca tcc tcc gga gag aga gag agg aag gag att 9631
Ile Arg Ile Arg Val Ala Ser Ser Gly Glu Arg Glu Arg Lys Glu Ile
380 385 390
cca cac agg ggt gga gtt tct gac gaa ggt cct aag gga gtg ttt gtg 9679
Pro His Arg Gly Gly Val Ser Asp Glu Gly Pro Lys Gly Val Phe Val
395 400 405
tct gac tca ggc gcc tgg cac att tca ggg aga aac tcc aaa gtc cac 9727
Ser Asp Ser Gly Ala Trp His Ile Ser Gly Arg Asn Ser Lys Val His
410 415 420 425
aca aag att ttc taa gga atg cac aaa ttg aaa aca cac tca aaa gac 9775
Thr Lys Ile Phe Gly Met His Lys Leu Lys Thr His Ser Lys Asp
430 435 440
aaa cat gca agt aaa gaa aaa aaa aag aaa gac ttt tgt tta aat ttg 9823
Lys His Ala Ser Lys Glu Lys Lys Lys Lys Asp Phe Cys Leu Asn Leu
445 450 455
taa aat gca aaa ctg aat gaa act gtt act acc ata aat cag gat atg 9871
Asn Ala Lys Leu Asn Glu Thr Val Thr Thr Ile Asn Gln Asp Met
460 465 470
ttt cat gaa tat gag tct acc tca cct ata ttg cac tct ggc aga agt 9919
Phe His Glu Tyr Glu Ser Thr Ser Pro Ile Leu His Ser Gly Arg Ser
475 480 485
att tcc cac att taa tta ttg cct ccc caa act ctt ccc acc cct gct 9967
Ile Ser His Ile Leu Leu Pro Pro Gln Thr Leu Pro Thr Pro Ala
490 495 500
gcc cct tcc tcc atc ccc cat act aaa tcc tag cct cgt aga agt ctg 10015
Ala Pro Ser Ser Ile Pro His Thr Lys Ser Pro Arg Arg Ser Leu
505 510 515
gtc taa tgt gtc agc agt aga tat aat att ttc atg gta atc tac tag 10063
Val Cys Val Ser Ser Arg Tyr Asn Ile Phe Met Val Ile Tyr
520 525 530
ctc tga tcc ata aga aaa aaa aga tca tta aat cag gag att ccc tgt 10111
Leu Ser Ile Arg Lys Lys Arg Ser Leu Asn Gln Glu Ile Pro Cys
535 540 545
cct tga ttt ttg gag aca caa tgg tat agg gtt gtt tat gaa ata tat 10159
Pro Phe Leu Glu Thr Gln Trp Tyr Arg Val Val Tyr Glu Ile Tyr
550 555 560
tga aaa gta agt gtt tgt tac gct tta aag cag taa aat tat ttt cct 10207
Lys Val Ser Val Cys Tyr Ala Leu Lys Gln Asn Tyr Phe Pro
565 570 575
tta tat aac cgg cta atg aaa gag gtt gga ttg aat ttt gat gta ctt 10255
Leu Tyr Asn Arg Leu Met Lys Glu Val Gly Leu Asn Phe Asp Val Leu
580 585 590
att ttt tta tag ata ttt ata ttc aaa caa ttt att cct tat att tac 10303
Ile Phe Leu Ile Phe Ile Phe Lys Gln Phe Ile Pro Tyr Ile Tyr
595 600 605
cat gtt aaa tat ctg ttg ggc agg cca tat tgg tct atg tat ttt taa 10351
His Val Lys Tyr Leu Leu Gly Arg Pro Tyr Trp Ser Met Tyr Phe
610 615 620
aat atg tat ttc taa atg aaa ttg aga aca tgc ttt gtt ttg cct gtc 10399
Asn Met Tyr Phe Met Lys Leu Arg Thr Cys Phe Val Leu Pro Val
625 630 635
aag gta atg act tta gaa aat aaa tat ttt ttt cct tac tgt ac 10443
Lys Val Met Thr Leu Glu Asn Lys Tyr Phe Phe Pro Tyr Cys
640 645 650
tgatttggaa tcattactga aatttgtaag gagtgggcca acgtgattaa gtaccataaa 10503
ggcaaataaa tggttaaaga cggtttcata gaaaagtgac aattagaagg atattacggt 10563
ctaagctaat tatataaaga attttatctg tatcttaaat gttgatttta tactgcattg 10623
aggtaaaaac acaaaacaaa aaagcagctt taacacctct gtcttctctt gggtagcagc 10683
ctcctgcttc tccttcacct gaaaaattct ccagggactt catccattaa cttggctcag 10743
gctattggca ggattcacag tttaagctga tggtgtggtg agagatgctt tatccatatt 10803
aatggactga aggaagtaat ggcaagacaa ccccccaaaa catacctaat tatacaaagt 10863
tatataccaa agttgctttt agaaaatggc ctgctcagag caagtagagg tttccaatgg 10923
ctttttattt tctcacatta aggatgttgt ttcttaagga acattgagta ccattgcttc 10983
ttcgtgatag cctaggactg ccgtgtgccc atggaggtag agacaccagg tactgattct 11043
aggtcctctg ccacaaagca ccacttcctc tccactttgc cttggctggc cttgtcagct 11103
cactggagag cacagtattg caattgcagt attgcaaatg gtcactacta actgaattct 11163
ctaagagctt gattagccct cgagaatctt ccttgccctt ctctaatagt gtctgaagga 11223
attcctggca tttaacaaat attagcatgt agtgatcact gtcgtcctaa cagtgacaca 11283
tcagaaggat ttcaaataac agtcttcagg catgcgtaat caatgtcctg tgcagagtct 11343
ccgtcctcat tgatcctcat ttttctcttt aaggcacagt ccaatgtctt tggggaattg 11403
tttataaagc ttactttatc cataaactgt ttctcagtgc gtgactctga agaaaatttt 11463
gaagttttgc ccatgttgac aaggtgcttg gtctgaactt ggccagtatt taatcttgag 11523
caaacgattc aatttccttc tatcgtgagt tttctcatct atgaaacaag ggagttgagg 11583
ggagtttctt tcatacctct gagaaagagt ttgagattac ataaagaagt tgaagtggca 11643
tgaaaaaaaa taaagatctg agcttagaag acatggatct aatacattta agaggaagtc 11703
agaatcagag aagccactga acaaaacagt ccaaacggag catagtaagt cagattgatg 11763
agttttggtt gggtttttca tcagtcaaac ccttgagccc ccctttccca tgcttcctgc 11823
ttcagtatcc agtaggaaaa atgaaaggga tgatgtagac actctagggc atgaggattt 11883
gcagtaaata agttgggaga ctcacagaaa attaatattt ttcaaacatg aagacgaaac 11943
attcaattat attacagtcc acatcagctt gaagggtaaa ctgatgggat gatctgtcac 12003
atttcttgct ctgtttccag taaaagcatg gtttctggaa acccacttag gacagctttc 12063
tctctttaca ctgatagccc aggcaagctt tgatctcaga actccagaaa ccagagaact 12123
ctaggtggaa tgtggtaact tttgccaggg cagagggaac acctactaat aggtacttca 12183
tttgcaccac cagagattgg catctttttt gatggatcca ctggctttga tactgcctgt 12243
actcccccaa aacacagctt gggtattgga ctaatctaga gctccctcag gagaactctt 12303
gctgacatta agaaagagca acattttgtc tttccaggtg aaaatccaag gccaaaaagg 12363
gagtgactca cctaagatca cagaaggagc tgtagcatct ctggagcctg aacacttaag 12423
ttaagcacga ctatttcacg cagagggcat gaattc 12459
2
20
DNA
Artificial sequence
Primer
2
ctccatcccc agaaaaactg 20
3
20
DNA
Artificial sequence
Primer
3
aaggaaggtg gtgctgagaa 20
4
20
DNA
Artificial sequence
Primer
4
gggggatttc aaggttagat 20
5
22
DNA
Artificial sequence
Primer
5
gagaagcccc gataagttct tt 22 | Disclosed are single nucleotide polymorphisms (SNPs) associated with hypertension, end stage renal disease due to hypertension non-insulin dependent diabetes mellitus, end stage renal disease due to non-insulin dependent diabetes mellitus, lung cancer, breast cancer, prostate cancer, colon cancer, atherosclerotic peripheral vascular disease due to hypertension, cerebrovascular accident due to hypertension, cataracts due to hypertension, cardiomyopathy with hypertension, myocardial infarction due to hyper-tension, atherosclerotic peripheral vascular disease due to non-insulin dependent diabetes mellitus, cerebrovascular accident non-insulin dependent diabetes mellitus, ischemic cardiomyopathy, ischemic cardiomyopathy with non-insulin dependent diabetes mellitus, myocardial infarction due to non-insulin dependent diabetes mellitus, atrial fibrillation without valvular disease, alcohol abuse, anxiety, asthma, chronic obstructive pulmonary disease, cholecystectomy, degenerative joint disease, end stage renal disease and frequent de-clots, end stage renal disease due to focal segmental glomerular sclerosis, end stage renal disease due to insulin dependent diabetes mellitus, or seizure disorder. Also disclosed are methods for using the SNPs to determine susceptibility to these diseases; nucleotide sequences containing the SNPs; kits for determining the presence of the SNPs; and methods of treatment or prophylaxis based on the presence of the SNPs. | 2 |
RELATED APPLICATIONS
[0001] The present application claims priority under 35 U.S.C. §119 of U.S. Application Ser. No. 61/151,393 filed Feb. 10, 2009.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0002] The present invention was partially made with Government support under grant R44HL066830 awarded by the US National Heart Lung and Blood Institute, National Institutes of Health. The Government has certain rights in the invention.
FIELD OF THE INVENTION
[0003] The present invention relates to methods and apparatus for high pressure fluid flow control. In more specific embodiments, the present invention relates to an improved, propellant-driven medical inhaler device for producing respirable aerosols of biologically-active substances, and to methods of using such devices. In further embodiments, the invention relates to electronically-controlled high pressure fluid flow valves and to devices and methods employing such valves, for example, to improve the performance of aerosol devices for aerosolized drug inhalation.
BACKGROUND OF THE INVENTION
[0004] Control of low flow rates of high pressure fluids is important in many fields including, but not limited to, supercritical fluid extraction, supercritical fluid chromatography, critical point drying, high pressure small parts cleaning, petrochemical processing, and biofuels production. Accordingly, the device in the present invention can be used advantageously in these fields to improve flow control of the high pressure fluids involved.
[0005] A very common method of administering biologically-active substances, such as asthma drugs, to the lungs involves the generation of respirable aerosols from pressurized metered dose inhalers (pMDIs). The typical pMDI comprises a small canister containing a suspension of drug particles or solution of dissolved drug in a compressed liquid propellant such as, formerly, CFC-11 and/or CFC-12, or, currently, HFA-134a. A mechanical means is used to fill a metering chamber with the pressurized suspension, and the chamber is allowed to decompress and spray out into an inhalation zone, flash evaporating the propellant and releasing airborne drug particles. Aerosols are generated by both the gas expansion energy and solvent evaporation.
[0006] Hand-held pressurized metered-dose inhalers (pMDIs) are commonly used to deliver bronchodilators and anti-inflammatory drugs to the lungs to treat asthma and chronic obstructive pulmonary diseases. Effective and safe aerosol delivery of pharmaceuticals to the lungs is limited by the solvents and propellants that can be used in inhalers. Until recently chlorofluorocarbon (CFC) propellants 11 (trichlorofluoromethane) and 12 (dichlorodifluoromethane) were the most commonly used propellant gases, but their use has been largely phased out in accordance with the Montreal Protocol due to the ozone-depleting properties of CFC propellants. Alternative propellants for pMDIs have become a necessary pursuit of the pharmaceutical industry. The Montreal Protocol is an international treaty that was drafted in 1987 to phase out the commercial production of all ozone-depleting CFCs. The US FDA, EPA, and DOE each have programs to eliminate production and use of all CFCs. The US FDA will not accept new drug applications for any MDI formulations that use CFCs as propellants. The EPA is expecting the pharmaceutical industry to comply with the Montreal Protocol as soon as proven alternative aerosol delivery techniques are developed for most pharmaceuticals.
[0007] Valves used to control high pressure fluid flow at low flow rates are problematic. U.S. Pat. No. 6,032,836 teaches that a metering chamber system can be used to deliver aliquots of high pressure fluid propellants such as liquid carbon dioxide to a low pressure inhalation zone, using a chamfered chamber region with a typical volume of 50 μL around a push pin mounted transversely to a high pressure inlet and low pressure outlet, for manual movement of the chamber from filling to discharging positions. Notably, the dose metering is based on the common approach of physically moving a metering chamber from a filling to discharging position, so it shares the drawbacks of this approach with standard, lower-pressure pMDIs charged with CFC or HFA propellants.
[0008] Unfortunately, pMDIs based on prior art have several problems and drawbacks. Notably, metered dose inhalers dispense aliquots of drug-containing propellant suspensions by capturing a small, fixed volume in a movable chamber under pressure and then opening this fixed volume chamber to room atmosphere so that the propellant can expand and drive the drug particles to become airborne. Such an approach has the problem that the movable chamber used to capture the aliquot is of fixed volume, so that the delivered drug amount is subject to change as the density of the propellant changes due to temperature changes, number of doses already administered from the canister, or other means. Plus, even under ideal temperature storage conditions, the dose size is fixed, and cannot be adjusted.
SUMMARY OF THE INVENTION
[0009] The present invention is provided to overcome one or more disadvantages of the prior art.
[0010] In one embodiment, the invention is directed to a fluid flow control valve which comprises (a) a high pressure region adapted to contain a fluid at its supercritical or nearcritical temperature and pressure conditions and connected via an orifice to a low pressure region, (b) a seat adjacent the orifice, (c) a sealing element positionable against the seat to form a seal between the high pressure region and the low pressure region, and (d) an electrically and/or electronically controlled actuator operable to move the sealing element against and/or away from the seat to allow control of fluid flow from the high pressure region to the low pressure region. In a specific embodiment, the high pressure region contains a fluid at its supercritical or nearcritical temperature and pressure conditions and the fluid comprises carbon dioxide, nitrogen, ethanol, difluoromethane, 1,1,1,2-tetrafluoroethane, or 1,1,1,2,3,3,3-heptafluoropropane, or a mixture of two or more thereof. The valve may be used, for example, to provide very low flow rates, for example, for supercritical fluid chromatography, supercritical fluid extraction, critical point drying, supercritical fluid cleaning, and supercritical fluid separation methods. In another embodiment, the valve is suitable for use in methods of delivering a biologically active substance to a patient in need thereof.
[0011] In another embodiment, the invention is directed to fluid flow control valve for aerosol delivery of biologically active materials for inhalation administration. The valve comprises (a) a high pressure region containing a pressurizable fluid and connected via an orifice to a low pressure region from which inhalation is conducted, (b) one or more biologically active substances dissolved and/or suspended in the pressurizable fluid, (c) a seat adjacent the orifice, (d) a sealing element positionable against the seat to form a seal between the high pressure region and the low pressure region, (e) an electrically and/or electronically controlled actuator operable to move the sealing element against and/or away from the seat to allow control of fluid flow from the high pressure region to the low pressure region, and (f) one or more electronic components operable to perform one or more functions of metered dose inhalation.
[0012] Additional features and embodiments of the invention will be apparent form the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Specific embodiments and features of the invention are depicted in the figures, using reference numerals as indicated, and these embodiments and features are illustrative and non-limiting of the invention described herein, wherein:
[0014] FIG. 1 is a schematic diagram depicting a cross section of the valve assembly (the valve) of the invention in a first embodiment.
[0015] FIG. 2 is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0016] FIG. 3 is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0017] FIG. 4 is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0018] FIG. 5 is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0019] FIG. 6 is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0020] FIG. 7 is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0021] FIG. 8 is a schematic diagram a cross section of depicting the valve of the invention in another embodiment.
[0022] FIG. 9 is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0023] FIG. 10A is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0024] FIG. 10B shows an enlarged view of the indicated portion of FIG. 10A .
[0025] FIG. 11A shows a perspective view depicting the valve of the invention in another embodiment.
[0026] FIG. 11B is a schematic diagram depicting a cross section of the valve of FIG. 11A , taken along the plane shown in FIG. 11A .
[0027] FIG. 12A shows a perspective view depicting the valve of the invention in another embodiment.
[0028] FIG. 12B is a schematic diagram depicting a cross section of the valve of FIG. 12A , taken along the plane shown in FIG. 12A .
[0029] FIG. 12C shows an enlarged view of the indicated portion of FIG. 12B .
[0030] FIG. 13 is a schematic diagram depicting the valve of the invention in another embodiment.
[0031] FIG. 14 is a schematic diagram depicting the valve of the invention in another embodiment.
[0032] FIG. 15A is a schematic diagram depicting a cross section of the valve of the invention in another embodiment.
[0033] FIG. 15B shows an enlarged view of the indicated portion of FIG. 15A .
[0034] FIG. 16 is a schematic diagram depicting the valve of the invention in another embodiment.
[0035] FIG. 17 is a schematic diagram depicting the valve of the invention in another embodiment.
[0036] The drawings will be more fully understood in view of the detailed description.
DETAILED DESCRIPTION
[0037] The invention provides various advantages in certain embodiments. For example, it is an advantage in certain embodiments of the invention to provide an electronically-controlled valve, which allows for improved control and easy record-keeping functions compared to mechanical valves currently used in high pressure fluid flow control valves in general and pressurized metered dose inhalers in particular.
[0038] It is a further advantage in certain embodiments of the invention that said electronically-controlled high pressure fluid control valve overcomes the problems of low flow rate control commonly associated with other valves currently used to control the flow of high pressure fluids, allowing precise metering of the flow of high pressure fluids instead of simply being in a discrete on or off state. This advantage can be realized in the present invention by variable valve opening, by controlled duration of valve opening, by controlled duration and frequency of rapid valve open/close cycling, or by a combination of such mechanisms.
[0039] It is a further advantage in certain embodiments of the invention that said electronically-controlled valve can be designed, tuned, and/or programmed to improve dose reproducibility relative to mechanically-controlled valves by compensating for temperature, doses already delivered, amount of propellant remaining in the canister, storage conditions between discharges, and other variables.
[0040] It is a further advantage in certain embodiments of the invention that said electronically-controlled valve can be programmed to allow adjustment of the delivered dose size based on the needs of the individual patient using it.
[0041] It is a further advantage in certain embodiments of the invention that said electronically-controlled valve can be programmed to prevent medication misuse and/or overdose by limiting the number of doses, controlling the minimum time between doses, requiring patient identification prior to dose delivery, counting doses delivered and/or remaining, and other relevant parameters.
[0042] It is a further advantage in certain embodiments of the invention that said electronically-controlled valve utilizes an electronic control system which facilitates control of oscillation frequency, pulse width modulation, vibration timing and amplitude, and other means to control the timing and repetition of valve opening and closure.
[0043] It is a further advantage in certain embodiments of the invention to provide a valve system which overcomes the problems of solids formation at the low pressure side of valves used to control flow of high pressure carbon dioxide solutions.
[0044] From the detailed description and diagrams herein, a number of additional advantages in certain embodiments of the present invention are evident: 1. The electronic control system can include an LCD counter display which can provide a 3 digit resolution counter for showing doses taken and doses remaining in the device. The electronic control system may work easier for dose counting than mechanical or other valve systems. 2. The electronically-controlled inhaler can notify audibly and/or visually when it is close to or at the last dose. 3. Electronic temperature compensation allows the electronically-controlled pMDI to be used at high and low temperatures, allowing its use in a broader temperature range than mechanical or other uncompensated pMDI systems. 4. Electronic counter can also be used for the electronically-controlled pMDI to self-compensate for pressure drop when the device is gradually emptied. 5. The electronically-controlled valve may not require a wasted priming puff.
[0045] Embodiments of the invention are depicted in FIGS. 1-17 . To facilitate clarity in the description of crucial aspects of the invention, well-known components, well-known electrical circuits, well-known fittings, and well-known procedures are not described in detail. The invention can, of course, take the form of additional embodiments, so the embodiments that are described are intended to describe and teach the invention without limiting the specific details of the invention.
[0046] The following reference numerals are used to designate the respective elements:
DRAWINGS
Reference Numerals
[0000]
1 high pressure region
2 pressurized fluid solution and/or suspension
3 low pressure region
4 seat
5 valve body
6 actuator
7 movement of fluid
8 plume of expanded fluid and aerosol particles
11 valve for pressure relief or filling or both
12 electrical connector
20 piezoelectric actuator
21 high pressure vessel
22 electrically-conductive standoff
23 electrically-conductive tether
24 electrically-conductive spring
25 electrically-insulating fastener
26 rigid beam
27 adjustable pushing pin
28 lever arm
29 Fulcrum
30 pushing means
31 Insulator
32 mounting arms
33 pushing pin
34 support pin
35 rigid mounting arm
36 pushing means
37 Post
38 support for electromagnetic windings
39 permanent ring magnet
40 permeable flux ring
41 permeable back material
42 nonconductive standoff
43 Fastener
44 U-shaped bimetal strip
45 insulating fastener
46 Wire
47 pressure seal insulator
50 piezoelectric disk
51 metal disk
52 adjustable mounting stud
53 mounting nut
54 exit tube
55 sealing film
56 threaded hole
57 leaf spring
58 rigid mounting arm
60 elastic beam
61 attachment point
62 mounting cylinder
63 electromagnetic wire windings
64 pushing means
65 magnetically permeable movable member
66 magnetically permeable housing
67 pushing means
68 bimetal strip
70 electric wire
71 Insulator
72 electric wire
[0106] In its simplest form, as depicted in FIG. 1 and FIG. 2 , the invented valve assembly comprises a high pressure region 1 containing a pressurized fluid solution and/or suspension 2 , a low pressure region 3 , a seat 4 , a valve body 5 which, when in the closed position, creates a seal between the high and low pressure regions, and an actuator 6 which, when engaged to open the valve, displaces the valve body and allows the movement 7 of said fluid from the high pressure region to the low pressure region, creating a plume of expanded fluid and aerosol particles 8 . The seat and valve body can be positioned within the low pressure region ( FIG. 1 ) or, alternatively, within the high pressure region ( FIG. 2 ). The actuator is preferably an electronically-controlled means to push or pull the valve body to displace it from the seat. Within the present description, electronically controlled is defined to mean that passing electric current through a component of the actuator causes the actuator to move and overcome a bias to push or pull the seal from the seat. Discontinuing the flow of current through the actuator component discontinues the force causing movement and the bias returns the seal to the seat. One of ordinary skill in the art will appreciate that the flow of current may be controlled in various respects, including rate and duration, to selectively dispense aerosol particles. In specific embodiments as discussed in detail below, the movement of the actuator can be achieved through contraction or expansion of a component or by generation of an electromagnetic force. Other embodiments resulting in movement of the actuator within the scope of the present invention will be apparent to one of ordinary skill in the art in view of the present disclosure.
[0107] FIG. 1 is a diagram depicting the valve assembly (valve) of the invention in a first embodiment. A high pressure region 1 containing a high pressure fluid and dissolved or suspended drug substance 2 , and a low pressure region 3 are separated by a valve body 5 positioned inside the high pressure region such that when the valve body is in the closed position it creates a seal against a seat 4 between the high and low pressure regions, and which can be opened by an electronically-driven actuator 6 and allow release at 7 of fluid and drug from the high pressure region to the low pressure region, and expansion of the fluid which forms an aerosol plume 8 . Notably, other pressurized fluids can be utilized instead of carbon dioxide in this invention, with those skilled in the art recognizing that the supercritical fluid solvent can be selected from a list of pressurized solvents including, but not limited to, carbon dioxide, HFC-134a (1,1,1,2-tetrafluoroethane), and HFC-227 (1,1,1,2,3,3,3-heptafluoropropane, aka HFC-227ea). Advantages to the general form of this embodiment with the valve body 5 in the high pressure region 1 include the use of such design as a fill valve to force high pressure fluids into the high pressure region.
[0108] FIG. 2 is a diagram depicting another embodiment of the valve assembly of the invention. A high pressure region 1 containing a high pressure fluid and dissolved or suspended drug substance 2 , and a low pressure region 3 are separated by a valve body 5 positioned in the low pressure region such that when the valve body is in the closed position it creates a seal against a seat 4 between the high and low pressure regions, and which can be opened by an electronically-driven actuator 6 and allow release at 7 of fluid and drug from the high pressure region to the low pressure region, and expansion of the fluid which forms an aerosol plume 8 . Notably, other pressurized fluids can be utilized instead of carbon dioxide in this invention, with those skilled in the art recognizing that the supercritical fluid solvent can be selected from a list of pressurized solvents including, but not limited to, carbon dioxide, HFC-134a (1,1,1,2-tetrafluoroethane), and HFC-227 (1,1,1,2,3,3,3-heptafluoropropane, aka HFC-227ea). Notably, this arrangement with the valve body 5 positioned in the low pressure region allows it to act as a pressure relief valve in case the pressure in the high pressure region 1 gets too high, because the actuator 6 can be adjusted so that it presses the valve body 5 against the set 4 with a low enough force that overpressure in the high pressure region 1 can force it open, making it the primary pathway for relief of pressure from the high pressure region 1 . Advantages to the general form of this embodiment with the valve body 5 in the low pressure region 1 include the aforementioned pressure relief valve usage and simplified electrical connectivity to valve components.
[0109] Hand held inhaler devices incorporating the present invention were built and tested for aerosol size distribution using pharmaceuticals that are commonly used for asthma treatment. In specific embodiments, pressurized carbon dioxide (CO 2 ) was employed, and several advantages to the use of pressurized CO 2 were established:
[0110] 1. CO 2 is a suitable MDI propellant replacement because it has zero ozone depletion potential and a global warming potential less than 0.1% of the new HFA propellants
[0111] 2. CO 2 MDI propellant generates aerosols in a narrow size range that are most likely to reach the lungs.
[0112] 3. CO 2 is the only propellant that can stimulate deep breathing and increase the deposition of aerosols in the lungs for more efficient delivery of pharmaceuticals.
[0113] 4. Many of the surfactants and solvent modifiers approved for inhaler formulations are very soluble in carbon dioxide.
[0114] 5. Many of the pharmaceuticals that are currently used to treat asthma are soluble in carbon dioxide.
[0115] 6. The toxicology of carbon dioxide is well understood because it has been in our lungs throughout human existence and has been used extensively in anesthesiology (especially Europe)
[0116] 7. The low reactivity of carbon dioxide is well known because it has been extensively studied for pharmaceutical extraction and processing.
[0117] 8. The high energy expansion of carbon dioxide can generate respirable aerosols of viscous liquids and sticky solids that cannot be collected for dry powder inhalers.
[0118] 9. Carbon dioxide has been used to generate pharmaceutical aerosols that have not been generated by any other method.
[0119] 10. Carbon dioxide MDIs can be used for both local lung therapy and systemic drug delivery.
[0120] FIGS. 3-17 disclose additional embodiments of the invention.
[0121] In another embodiment, depicted in FIG. 3 , the actuator 6 comprises a shape memory alloy (SMA) wire 6 mounted within the high pressure region 1 by attachment to an electrically-conductive standoff 22 and connected to an electrically-conductive valve body 5 which in this embodiment is pin-shaped and seated against an electrically-insulating seat 4 and pulled down into sealing position in the low pressure region 3 by an electrically-conductive tether 23 which is partially coiled into a spring form 24 , electrically-isolated at the low pressure end by insulator 25 , so that when electrical current is passed through the shape memory alloy (SMA) wire actuator 6 , it contracts and breaks the seal between the valve body 5 in the form of a pin and the seat 4 so that the high pressure fluid 2 contained within the vessel 21 is allowed to be released into the low pressure region 3 . The SMA wire material can include, but is not limited to, a nickel titanium alloy known as Nitinol in which heat treatment while under stress to stretch the material results in an elongated shape which attempts to revert back to its original shape when heated to a temperature above its transformation temperature, as accomplished by resistive heating in the present example. Also depicted in this embodiment is a valve 11 for filling, pressure relief, or both, adding advantages of convenient filling and pressurization and enhanced safety.
[0122] In another embodiment, depicted in FIG. 4 , the actuator 6 comprises a shape memory alloy (SMA) wire 6 mounted within the high pressure region 1 by attachment to an electrically-conductive standoff 22 and connected to an electrically-conductive valve body 5 which in this embodiment is ball-shaped and seated against an electrically-insulating seat 4 and pulled down into sealing position in the low pressure region 3 by an electrically-conductive tether 23 which is partially coiled into a spring form 24 , electrically-isolated at the low pressure end by insulator 25 , so that when electrical current is passed through the SMA wire actuator 6 , it contracts and breaks the seal between the valve body 5 in the form of a ball and the seat 4 so that the high pressure fluid 2 contained within the vessel 21 is allowed to be released into the low pressure region 3 .
[0123] In another embodiment, depicted in FIG. 5 , the actuator 6 comprises a shape memory alloy (SMA) wire 6 mounted within the high pressure region 1 by attachment to an electrically-conductive standoff 22 and connected to an electrically-conductive valve body 5 which, in this embodiment, is pin-shaped and seated against an electrically-insulating seat 4 , so that when electrical current is passed through the electrical connector 12 , the pin 5 , the SMA wire actuator 6 , the electrically conductive standoff 22 , and the electrically conductive pressure vessel body 21 , the SMA wire contracts and breaks the seal between the valve body 5 and the seat 4 so that the high pressure fluid 2 contained within the vessel 21 is allowed to be released into the low pressure region 3 . The internal pressure in the high pressure region 1 holds the pin in a position which facilitates sealing and resealing after opening.
[0124] In another embodiment, depicted in FIG. 6 , the actuator comprises a pushing means such as a piezoelectric actuator 20 pushing across an intervening insulator 71 to a lever arm 28 mounted to a fulcrum 29 . The lever arm includes at the opposite end an adjustable push pin 27 pressing on a sealing element 5 , which in this example is ball-shaped, to seat it against the sealing seat 4 when in the closed position and thereby contain the fluid and dissolved or suspended drug 2 in the high pressure region 1 contained within a high pressure vessel 21 . In this embodiment, when the piezoelectric actuator 20 is induced to contract by passing electric current through it via electric wire 70 and either through a second electric wire at its other end where it contacts the pressure vessel 21 or through electrical contact of the piezoelectric actuator 20 to the pressure vessel 21 and grounding of said vessel at another location, said contraction allows the sealing element 5 to unseat from the sealing seat 4 , allowing high pressure fluid and dissolved or suspended drug 2 to be released from the high pressure vessel 21 into the low pressure region 3 .
[0125] In another embodiment, depicted in FIG. 7 , the actuator 6 comprises a shape memory alloy (SMA) wire 6 mounted in the low pressure region 3 by attachment with an intervening insulator 31 to a lever arm 28 pivoting on a fulcrum 29 with the opposite end pressed with a spring or other pushing means 30 so that the adjustable pin 27 in said lever arm presses a sealing means 5 , which in this embodiment is ball-shaped, to seat it against the sealing seat 4 when in the closed position and thereby contain the fluid and dissolved or suspended drug 2 in the high pressure region 1 contained within a high pressure vessel 21 . The arm 28 can be made thin enough to apply spring force itself to the pin 27 and sealing means 5 . In this embodiment, when electrical current is passed through the SMA wire actuator 6 , it contracts and pulls the lever arm 28 hard enough to overcome the pushing means 30 , such as a spring, and unseat the sealing means 5 from the sealing seat 4 , allowing high pressure fluid and dissolved or suspended drug 2 to be released from the high pressure vessel 21 into the low pressure region 3 .
[0126] In another embodiment, depicted in FIG. 8 , the actuator 6 comprises a shape memory alloy (SMA) wire 6 mounted in the low pressure region 3 by attachment of each end of 6 using insulators 31 to mounting arms 32 out from the sealing seat 4 and with said SMA wire 6 connected to the sealing means 5 which in this embodiment is ball-shaped and seated against a seat 4 when in the closed position. Said sealing means 5 is pressed against said seat 4 by a pushing pin 33 that has adjustable position by its connection to a support pin 34 mounted to a rigid mounting arm 35 and including a pushing means 36 , such as a spring, so that when electrical current is passed through the SMA actuator 6 , it pulls the sealing means 5 away from the sealing seat to break the seal between the sealing means ball 5 and the seat 4 so that the high pressure fluid and dissolved or suspended drug 2 contained within the vessel 21 is allowed to be released into the low pressure region 3 . This embodiment has the advantage that the cooling effect of the fluid expansion from the high pressure region 1 to the low pressure region 3 cools the SMA wire actuator 6 , reducing the response time and improving control.
[0127] In another embodiment, depicted in FIG. 9 , the actuator comprises a magnetically permeable movable member 65 with a push post 37 exerting force against a valve body 5 , which is ball-shaped in this embodiment, to press it against a seat 4 when in the closed position to create a seal and capture the high pressure fluid and dissolved or suspended drug 2 within the high pressure region 1 contained within the pressure vessel 21 . The moveable member 65 and post 37 are pressed into position by a pushing means 64 , such as a spring, with enough force to seat the valve body 5 against the seat 4 , and when electrical current is directed through the electromagnetic wire windings 63 wound around a magnetically permeable housing 66 a magnetic field is generated which attracts the moveable member 65 towards the pushing means 64 with enough force and/or momentum to open the seal between the valve body ball 5 and the seat 4 so that the high pressure fluid and dissolved or suspended drug 2 contained within the vessel 21 is allowed to be released into the low pressure region 3 .
[0128] In another embodiment, depicted in FIG. 10 , the actuator comprises a support for electromagnetic windings 38 , such as in a voice coil, integrally bonded to electromagnetic wire windings 63 and with a push post 37 exerting force against a valve body 5 , which is ball-shaped in this embodiment, to press it against a seat 4 when in the closed position to create a seal and capture the high pressure fluid and dissolved or suspended drug 2 within the high pressure region 1 contained within the pressure vessel 21 . The support for electromagnetic windings 38 and post 37 are pressed into position by a pushing means 67 , such as a spring, with enough force and/or momentum to seat the valve body 5 against the seat 4 , and when electrical current is directed through the electromagnetic wire windings 63 bound to the voice coil housing, a magnetic field is generated which attracts the support for electromagnetic windings 38 towards the permanent ring magnet 39 using magnetic flux traveling through a permeable flux ring 40 and permeable back material 41 , so that the support for electromagnetic windings 38 and post 37 are pulled towards the pushing means 67 with enough force and/or momentum to open the seal between the valve body 5 and the seat 4 so that the high pressure fluid and dissolved or suspended drug 2 contained within the vessel 21 is allowed to be released into the low pressure region 3 .
[0129] In another embodiment, depicted in FIG. 11 , the actuator comprises a U-shaped bimetal strip 44 mounted in the low pressure region 3 by attachment of each end of 44 using nonconductive standoffs 42 and fasteners 43 so that the middle of the U-shape of the bimetal strip presses against a sealing means 5 which in this embodiment is ball-shaped and seats it against a seat 4 when in the closed position. Said U-shaped bimetal strip 44 is preloaded to force the sealing means 5 against the seat 4 , and when electrical current is passed through the U-shaped bimetal strip 44 , it bends away from the sealing means 5 and the sealing seat 4 , breaking the seal between the sealing means 5 and the seat 4 so that the high pressure fluid and dissolved or suspended drug 2 contained in the high pressure region 1 within the vessel 21 is allowed to be released into the low pressure region 3 . The amount of flow allow to be released from the high pressure region 1 is controlled by the intensity and duration of the electrical pulse applied through the bimetal strip. This embodiment has the advantage that the cooling effect of the fluid expansion from the high pressure region 1 to the low pressure region 3 cools the bimetal strip 44 , reducing the response time and improving control. In this embodiment is also depicted a fill or pressure relief valve 11 .
[0130] In another embodiment, depicted in FIG. 12 , the actuator comprises a bimetal strip 68 mounted in the low pressure region 3 in a spring-like fashion by rolling over each end of 68 and attaching each end of 68 using nonconductive standoffs 42 and fasteners 43 so that the middle of said bimetal strip presses against a sealing means 5 which in this embodiment is ball-shaped and seats said sealing means 5 against a sealing seat 4 when in the closed position. Said bimetal strip 68 is preloaded to force the sealing means 5 against the seat 4 , and when electrical current is passed through the bimetal strip 68 , it bends away from the sealing means 5 and the sealing seat 4 , breaking the seal between the sealing means 5 and the seat 4 so that the high pressure fluid and dissolved or suspended drug 2 contained in the high pressure region 1 within the vessel 21 is allowed to be released into the low pressure region 3 . In typical use, the center of the bimetal strip 68 would be narrower than the ends so that the voltage drop is higher at the site of contact with the sealing means 5 . In this way, when current is passed through the bimetal strip 68 , using for example electric wire 72 to connect to each end of said bimetal strip, most of the heating and deflection occurs in the narrow region of the bimetal strip 68 , and cooling of the bimetal strip 68 occurs due to the expanding fluid flow, which serves to improve valve control. In this embodiment is also depicted a valve 11 used for filling and/or pressure relief purposes.
[0131] In another embodiment, depicted in FIG. 13 , the actuator 6 comprises a shape memory alloy (SMA) wire 6 mounted within the high pressure region 1 by attachment to an electrically-conductive standoff 22 , in this example a rigid metal tubular structure, and connected to an electrically-conductive valve body 5 , which in this embodiment is pin-shaped and seated against an electrically-insulating seat 4 , and pushed down into sealing position by pressure in the high pressure region 1 and pulled down into sealing position by an electrically-conductive tether 23 in the low pressure region 3 such that said tether 23 is attached using an electrically insulating fastener 25 to a leaf spring 57 attached to the pressure vessel 21 by means of a rigid mounting arm 58 , so that the valve body 5 is pulled into a sealing position by the leaf spring 57 when in the closed position but when electrical current is passed through the SMA wire actuator 6 , it contracts and breaks the seal between the valve body 5 and the seat 4 so that the high pressure fluid 2 contained within the vessel 21 is allowed to be released into the low pressure region 3 . Further, when no current is passed through the SMA wire 6 , the leaf spring 57 and the internal pressure in the high pressure region 1 within the pressure vessel 21 both facilitate reseating of the valve body 5 against the seat 4 , stopping the release of high pressure fluid and drug 2 from the pressure vessel 21 into the low pressure region 3 . This embodiment has the advantage that the heated SMA wire actuator 6 in the high pressure region 1 allows preheating of the high pressure fluid during actuation of the valve.
[0132] In another embodiment, depicted in FIG. 14 , the actuator 6 comprises a shape memory alloy (SMA) wire 6 with a bend in the middle mounted within the high pressure region 1 by passing each end of the SMA wire 6 through insulating fasteners 45 and attachment of fastener 45 to a standoff 22 and fastening of each end of the SMA wire 6 to the standoff by means of the insulating fasteners 45 . Said SMA wire 6 is connected at said bend in middle to a valve body 5 , which in this embodiment is pin-shaped and seated against a seat 4 and pushed down into sealing position by pressure in the high pressure region 1 when in the closed position. Each end of the SMA wire 6 is further connected to conductive wires 46 which pass through pressure seal insulators 47 facilitating the passage of electrical current from access to the wires 46 in the low pressure region 3 to actuate the SMA wire 6 so that it contracts and pulls the valve body 5 away from the seat 4 so that the seal is broken and the high pressure fluid and drug 2 contained in the high pressure region 1 within the vessel 21 is allowed to be released into the low pressure region 3 .
[0133] In another embodiment, depicted in FIG. 15 , the actuator comprises a piezoelectric disk 50 conductively and mechanically bonded to a metal disk 51 mounted to the pressure vessel 21 by means of a multiplicity of adjustable mounting studs 52 threaded into mounting nuts 53 and threaded holes 56 attached to the pressure vessel 21 . Location of said bonded piezoelectric disk 50 and metal disk 51 are adjusted so that a sealing film 55 bonded to the disk 51 surface opposite the piezoelectric disk 50 presses against an exit tube 54 attached to the pressure vessel 21 so that the inside of the tube 54 is contiguous with the high pressure region 1 containing the pressurized fluid and drug 2 and so that the contact between the sealing film 55 and the exit tube 54 create a seal and prevent the high pressure fluid and drug 2 from release into the low pressure region 3 when in the closed position. Further, application of DC bias voltage and/or oscillating voltage to the piezoelectric disk 50 induces it to move and break the seal between the sealing film 55 and the tube 54 allowing controlled release of high pressure fluid and drug 2 contained in the vessel 21 to pass through the tube 54 and out of the open end of the tube 54 into the low pressure region 3 .
[0134] In another embodiment, depicted in FIG. 16 , the actuator comprises a piezoelectric disk 50 conductively bonded to a metal disk 51 mounted to the pressure vessel 21 by means of a multiplicity of adjustable mounting studs 52 threaded into mounting nuts 53 and threaded holes 56 attached to the pressure vessel 21 . Location of said bonded piezoelectric disk 50 and metal disk 51 are adjusted so that the disk 51 surface opposite the piezoelectric disk 50 presses against a sealing means 5 , in this embodiment ball-shaped, seated at the end of an exit tube 54 which is attached to the pressure vessel 21 so that the inside of the tube 54 is contiguous with the high pressure region 1 containing the pressurized fluid and drug 2 . Further, said pressing of the sealing means 5 against the end of the exit tube 54 creates a seal and prevents the high pressure fluid and drug 2 from release into the low pressure region 3 when in the closed position. Further, application of DC bias voltage and/or oscillating voltage to the piezoelectric disk 50 induces it to move and break the seal between the sealing means 5 and the tube 54 allowing controlled release of high pressure fluid and drug 2 contained in the vessel 21 to pass through the tube 54 and out of the open end of the tube 54 into the low pressure region 3 .
[0135] In another embodiment, depicted in FIG. 17 , the actuator 6 comprises a shape memory alloy (SMA) wire 6 mounted in the low pressure region 3 by attachment of each end of 6 using insulating fasteners 45 to rigid mounting arms 58 . This embodiment further comprises an exit tube 54 which is attached to the pressure vessel 21 so that the inside of the tube 54 is contiguous with the high pressure region 1 containing the pressurized fluid and drug 2 , a mounting cylinder 62 holding a cutaway disk possessing an elastic beam 60 across its center, positioned so that said beam 60 presses against a valve body 5 , in this case ball-shaped, seated at the end of said exit tube 54 . Further, said pressing of the valve body 5 against the end of the exit tube 54 creates a seal and prevents the high pressure fluid and drug 2 from release into the low pressure region 3 when in the closed position. Further, the SMA wire 6 is attached to the middle of the elastic beam at the middle of the SMA wire 6 by means of an attachment point 61 on the elastic beam such that passage of electrical current through the SMA wire 6 induces it to contract and pull on the elastic beam 60 and break the seal between the valve body 5 and the tube 54 allowing controlled release of high pressure fluid and drug 2 contained in the vessel 21 to pass through the tube 54 and out of the open end of the tube 54 into the low pressure region 3 .
[0136] Skilled persons will appreciate that the present invention facilitates flow control of high pressure fluids and provides an electronically-controlled valve for use in an electronic metered dose inhaler with many advantages over existing devices.
[0137] The following examples illustrate certain embodiments of the invention.
Example 1
[0138] A valve according to FIG. 5 is constructed and mounted onto an aluminum canister pressure vessel with an internal volume of 12 mL, incorporating a shape memory alloy actuator wire conductively mounted to an electrically-conductive standoff inside the canister, and a gold-plated metal pin as the sealing element seated against an elastomeric seat. The canister is pressurized to about 900 psi with carbon dioxide, and metered releases of carbon dioxide gas are effected by application of sufficient current to the shape memory alloy wire to cause it to contract and pull the pin away from the seat. After each release of pressurized gas from the canister into room pressure, after stopping the application of DC current to the shape memory alloy wire actuator, the pin returns to the closed position against the seat and the flow stops. The process is repeated several times. Finally, after pressurizing the canister with 2.88 g of carbon dioxide and sealing the canister with the aforementioned gold pin against the elastomeric seat, the leak rate was measured. After 480 days, 97.8% of the originally-loaded carbon dioxide is still contained within the canister, indicating a low leak rate and a good valve seal.
Example 2
[0139] A valve according to FIG. 11 is constructed so that the metal ball sealing element, 1 mm diameter, is seated into the end of a 1.6 mm outer diameter stainless steel tube into which an internal beveled edge had been cut to facilitate seating of the ball against the tube. The ball is pressed into place with a U-shaped bimetal strip, preloaded with enough tension to hold the ball sealed against the tube when 2000 psi of pressure is applied inside the tube, and 2000 psi is maintained going into the tube with carbon dioxide. When current is passed through the bimetal strip, it bends away from the tube, sufficiently to allow the ball to move away from the tube and allow carbon dioxide to flow out of the tube into room pressure. It is determined that the flow rate is proportional to the amount of electrical current passed though the bimetal strip, and the valve is demonstrated to open and close through dozens of cycles of applying electrical current.
Example 3
[0140] A valve according to FIG. 15 is constructed using a 0.4 mm OD tube through which flow is controlled from a region of 900 psi carbon dioxide to room pressure. A thin layer of polyurethane, approximately 0.2 mm thick, is applied to the surface of a 20 mm diameter brass disk on the opposite side from piezoelectric ceramic material conductively attached to the disk, also known as a piezoelectric bender. The disk is mounted perpendicular to the tube with the urethane coating pressed against the end of the tube with sufficient force to seal the tube against flow of the 900 psi carbon dioxide into the room pressure region. Eighty volts DC are applied to the piezoelectric bender, along with 6 kHz oscillating voltage, which bends the disk away from the tube and allows carbon dioxide flow to exit the tube. This actuation is repeatedly tested for 2500 on/off cycles of 0.8 sec on and about 7 sec off, and the valve is found to repeatedly release metered pulses of carbon dioxide gas and then reseal at the end of the test.
Example 4
[0141] A valve according to FIG. 15 is constructed using a 0.4 mm OD tube through which flow is controlled from a region of approximately 80 psi of 1,1,1,2-tetrafluoroethane (HFC-134a) to room pressure. A thin layer of polyurethane, approximately 0.2 mm thick, is applied to the surface of a 20 mm diameter brass disk on the opposite side from piezoelectric ceramic material conductively attached to the disk, also known as a piezoelectric bender. The disk is mounted perpendicular to the tube with the urethane coating pressed against the end of the tube with sufficient force to seal the tube against flow of the 80 psi 1,1,1,2-tetrafluoroethane into the room pressure region. One hundred ten volts DC are applied to the piezoelectric bender, along with oscillating voltage, 8 kHz, 10 volts AC, which bends the disk away from the tube and allows 1,1,1,2-tetrafluoroethane flow to exit the tube. This actuation is repeatedly tested for 1000 on/off cycles of 0.8 sec on and about 7 sec off, and the valve is found to repeatedly release metered pulses of 1,1,1,2-tetrafluoroethane gas and then reseal at the end of the test.
[0142] The various examples and embodiments described herein are illustrative in nature only and are non-limiting of the invention defined by the claims. | A fluid flow control valve comprises (a) a high pressure region adapted to contain a fluid at its supercritical or nearcritical temperature and pressure conditions and connected via an orifice to a low pressure region, (b) a seat adjacent the orifice, (c) a sealing element positionable against the seat to form a seal between the high pressure region and the low pressure region, and (d) an electrically and/or electronically controlled actuator operable to move the sealing element against and/or away from the seat to allow control of fluid flow from the high pressure region to the low pressure region. In a specific embodiment, the high pressure region contains a fluid at its supercritical or nearcritical temperature and pressure conditions. The valve may be used, for example, to provide very low flow rates, for example, for supercritical fluid chromatography, supercritical fluid extraction, critical point drying, supercritical fluid cleaning, and supercritical fluid separation methods. In another embodiment, the valve is suitable for use in methods of delivering a biologically active substance to a patient in need thereof. | 0 |
CROSS REFERENCE TO RELATED APPLICATION(S)
This is a divisional application based on application Ser. No. 10/921,972, filed Aug. 20, 2004, now U.S. Pat. No. 7,270,637 the entire contents of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for and method of measuring blood flow. More particularly, the present invention relates to a device for and method of measuring blood flow using bio-photon emission.
2. Description of the Related Art
Cardiovascular diseases (CVDs), along with cancers, are regarded as the most life threatening illnesses to modern human beings. Among CVDs, a cerebral apoplexy, i.e., a stroke, occurs when, due to hardening of the arteries and cholesterol collected on the walls of blood vessels in the brain, the blood vessels become narrow or clogged. Thrombus may be produced in portions of a body, such as the heart and its adjacent organs, where the arteries are hardening. In addition, mental stress reduces the amount of blood that flows into the heart, thus resulting in a high probability of death from heart disease.
Generally, death from heart disease most likely occurs in patients whose coronary arteries, which send blood to the heart, narrow by 50% in at least one portion of the coronary arteries or who have already had one or more heart attacks.
An ischemic stroke can be categorized into two types, a complete ischemic stroke or a partial ischemic stroke depending on how blood circulation disorder is affected. In a case of a complete ischemic stroke, blood circulation in a portion of the brain is completely cut off, and a cerebral infarction occurs. Since a cerebral infarction makes the portion of the brain in which it occurs functionally irrecoverable, disorders due to the cerebral infarction are permanent.
A transient ischemic attack (TIA) is transient and includes local neurological symptoms due to a transient reduction of the blood supply to the brain. A TIA causes symptoms similar to a stroke, but differs from the stroke in that the TIA is only a temporary disease. In particular, a TIA may last for several minutes and then disappear. A TIA is a warning signal that a patient might have a stroke later due to dysfunctional blood circulation in the brain.
A conventional method of measuring an amount or rate of blood flow can be categorized into a method using the Doppler effect and a method using electromagnetic induction. Further, the method using the Doppler effect is classified into a method using a laser and a method using ultrasonic waves. When a laser Doppler blood flowmeter is used, the rate of blood that flows through blood vessels is measured by inserting a glass fiber into a blood vessel and irradiating a laser beam in the blood vessel. Then, the rate of blood is measured using a variation of wavelength of a reflected light. When an ultrasonic blood flowmeter is used, blood flow is measured using a variation of an ultrasonic wave that is externally applied to blood. A fundamental principle of the ultrasonic blood flowmeter is the same as that of the laser Doppler blood flowmeter. An electromagnetic blood flowmeter measures the amount or rate of blood flow by detecting an electromotive force (EMF) of blood generated after a magnetic field is applied to blood vessels.
Disadvantageously, measurement results of blood flow using the aforementioned conventional blood flowmeters are not precise because signals are affected by a stimulus to a human body or tissues inside or outside the skin. In addition, because these blood flowmeters are bulky, they are quite difficult to use, install, or transport.
SUMMARY OF THE INVENTION
The present invention is therefore directed to a device for and method of measuring blood flow using bio-photon emission, which substantially overcome one or more of the problems due to the limitations and disadvantages of the related art.
It is a feature of an embodiment of the present invention to provide a device for and method of measuring blood flow using bio-photon emission that are economical and relatively simple.
It is another feature of an embodiment of the present invention to provide a device for and method of measuring blood flow using bio-photon emission that provide real time measurements to a patient being examined.
It is another feature of an embodiment of the present invention to provide a device for and method of measuring blood flow using bio-photon emission that are able to be connected to various communication devices to enable remote treatment and accumulation of information.
At least one of the above features and other advantages may be provided by a device for measuring a blood flow of a living body having blood vessels that emit bio-photons and through which blood flows, the device including a detector positioned adjacent to a predetermined portion of the living body for measuring a bio-photon emission from the living body and a processor for analyzing and displaying the blood flow of the living body based on a value of the bio-photon emission.
The device may further include a shutter for controlling an amount of light incident on the detector. The detector may operate in a darkroom. The detector may be a photomultiplier or an optical receiver.
The device may further include a power supply for supplying power to the detector, a conveyor operable to move the detector three-dimensionally, and a preamplifier for converting the bio-photon emission detected by the detector into an electric signal and amplifying the electric signal.
The conveyor may include a stand, a support fixed on the stand, and a convey arm attached to the support operable to three-dimensionally control the movement of the detector.
The processor may include a display unit. The device may further include a communication device for transmitting results of the analysis of the bio-photon emission.
At least one of the above features and other advantages may be provided by a method of measuring a blood flow of a living body having blood vessels that emit bio-photons and through which blood flows, the method including measuring a bio-photon emission using a detector, converting the bio-photon emission into an electric signal and amplifying the electric signal, calculating an amount of bio-photon emission measure per unit of time I D based on the amplified electric signal, comparing the amount of bio-photon emission per unit time I D with a preset value, and displaying a result of the comparison.
Comparing the amount of bio-photon emission per unit time I D with the preset value may be performed using the following inequality:
I D - I ref I ref × 100 ≥ I th ,
wherein I ref is an average of amounts of bio-photon emissions measured on the living body for several previous days and I th is the preset value.
The method may further include issuing a warning signal to the user if
I D - I ref I ref × 100
is greater than or equal to the preset value I th .
Measuring the bio-photon emission may include positioning the detector adjacent to a predetermined portion of the living body, opening a shutter on the detector, and receiving the bio-photon emission by the detector.
Measuring the bio-photon emission may be performed in a darkroom.
The method may further include transmitting the result of the comparison using a communication device.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
FIG. 1 illustrates a device for measuring blood flow using bio-photon emission according to an embodiment of the present invention; and
FIG. 2 is a flowchart illustrating a method of measuring blood flow using bio-photon emission according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Korean Patent Application No. 2004-02031, filed on Jan. 12, 2004, in the Korean Intellectual Property Office, and entitled: “Device for and Method of Measuring Blood Flow Using Bio-Photon Emission,” is incorporated by reference herein in its entirety.
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. The invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
FIG. 1 illustrates a device for measuring blood flow using bio-photon emission according to an embodiment of the present invention.
Referring to FIG. 1 , a blood flow measurement device 100 includes a power supply 102 , a detector 120 , which may be a photomultiplier (PMT) or an optical receiver, a preamplifier 106 , a processor 108 , such as a computer/counting board, which may include a display, and a conveyor including a convey arm 122 , a support 124 , and a stand 126 . In operation, the power supply 102 supplies power to the blood flow measurement device 100 . The PMT 120 measures a bio-photon emission generated from an object 110 . The preamplifier 106 converts the measured bio-photon emission into an electric signal and amplifies the electric signal. The processor 108 calculates the bio-photon emission using the amplified electric signal from the preamplifier 106 . The convey arm 122 moves the detector 120 , and the support 124 supports the convey arm 122 . A shutter 121 is attached to the detector 120 to control an amount of light that is incident on the detector 120 .
In the present embodiment, the detector 120 is three-dimensionally movable. By controlling the detector 120 using the convey arm 122 , which is attached to the support 124 fixed to the stand 126 , the detector 120 may be positioned adjacent to the object 110 , i.e., a living body such as a human body. In the context of the present invention, adjacent may mean in contact with or in close proximity.
Thereafter, the shutter 121 attached to the detector 120 , which has been previously turned on, is opened. The shutter 121 remains closed until measurement begins because the detector 120 is susceptible to damage caused by exposure to light.
The detector 120 is able to measure the bio-photon emission, which is much dimmer than starlight. It is impossible to measure the bio-photon emission using a typical method of measuring light. The bio-photon emission may be measured in a darkroom.
The present invention is based on an assumption that the bio-photon emission varies with a state of the human body. In an embodiment of the present invention using a photomultiplier (PMT) as the detector, since the PMT, which typically measures a bio-photon emission of a solid, amplifies one photon by a factor of a million to allow the bio-photon emission to be measured, the PMT should be manufactured to measure ultrafaint light. The PMT is able to measure an amount of light radiated by a single bio-photon and thus, it can be referred to as a single photon counting.
The bio-photon emission measured by the detector 120 is displayed by the processor 108 through the preamplifier 106 so that a user is informed of a measurement result in real time. The preamplifier 106 converts the bio-photon emission measured by the detector 120 into an electric signal, or a voltage, amplifies the electric signal, and outputs the amplified electric signal to the processor 108 .
In an embodiment of the present invention, measurement of the bio-photon emission may be performed for about thirty (30) seconds after a dark level is measured.
In an embodiment of the present invention, the device may further include a communication device 112 . The communication device 112 is capable of transmitting results of the analysis of the bio-photon emission, thereby enabling remote treatment and accumulation of information on the health states of individuals.
When an experiment was conducted according to an embodiment of the present invention, a relationship between blood pressure and the measured bio-photon emission was identified as shown in the Table 1.
TABLE 1
Blood pressure
Bio-photon emission
60
200
70
170
80
150
110
140
Referring to Table 1, it may be seen that as the blood pressure increases, the bio-photon emission decreases. Accordingly, when the blood flow measurement device 100 is used, it is possible to measure the bio-photon emission generated from a living body and predict a state of blood flow based on the measured bio-photon emission, thereby facilitating diagnosis of a health state of the living body.
FIG. 2 is a flowchart illustrating a method of measuring blood flow using bio-photon emission, the method being performed in the device of FIG. 1 .
Hereinafter, the method shown in FIG. 2 will be described with reference to the blood flow measurement device 100 shown in FIG. 1 .
In operation S 10 , a user positions the detector 120 adjacent to an object 110 , i.e., a living body, by controlling the convey arm 122 and opens the shutter 121 , thereby allowing the detector 120 to receive bio-photon emission.
In operation S 20 , the bio-photon emission received by the detector 120 is converted into an electric signal, which is amplified by the preamplifier 106 , and then output to the processor 108 .
In operation S 30 , an amount I D of bio-photon emission measured per unit of time is calculated by the processor 108 based on the amplified electric signal.
Next, in operation S 40 , a presence of a disorder of the living body may be determined using the following inequality:
I D - I ref I ref × 100 ≥ I th ( 1 )
wherein I ref is an average of the amounts of bio-photon emissions that have been measured from the living body for several days before the present measurement, and I th is a preset critical value. If I th is preset to 20, when the measured I D is greater than +20% or less than −20%, the calculated value,
I D - I ref I ref × 100 ,
exceeds the critical value I th .
If, in operation S 40 , it is determined that the calculated value is equal to or less than the critical value I th , then, in operation S 50 , measured data and evaluation thereof can be displayed on a display unit (not shown), for example, a liquid crystal display (LCD).
If, however, in operation S 40 , it is determined that the calculated value exceeds the critical value I th , then, in operation S 60 , a warning signal, such as a beep, is sent to the user and measured data and evaluation thereof are displayed on the display unit. The evaluation may include a notice of a blood flow abnormality along with an analysis of the associated disorder.
The method may additionally include, in operation S 70 , transmitting results of the analysis of the bio-photon emission via the communication device 112 .
As described above, the present invention provides information on blood flow by using bio-photon emission, which varies with a state of a human body, as a bio signal without having to apply any physical, chemical, or physiological stimulus to the human body.
In comparison with conventional blood flowmeters, which are time-consuming to use and thus, incur significant cost, the method and device of an embodiment of the present invention are economical and relatively simple.
Also, the present invention enables real time measurement so that a patient being examined may be instantaneously informed of the results and promptly take necessary measures based on the measurement results.
Further, since the bio-photon emission is converted into an electric signal, the device of the present invention can be directly connected to various communication devices, thereby enabling remote treatment and accumulation of information on the health states of individuals.
Exemplary embodiments of the present invention have been disclosed herein and, although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims. | A device for and a method of measuring a blood flow of a living body having blood vessels that emit bio-photons and through which blood flows, the device including a detector positioned adjacent to a predetermined portion of the living body for measuring a bio-photon emission from the living body and a processor for analyzing and displaying the blood flow of the living body based on a value of the bio-photon emission. | 0 |
[0001] This application is a continuation of application no. PCT/EP2005/050141, filed Jan. 14, 2005, which claims the priority of European application no. 04100556.2, filed Feb. 13, 2004, and each of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a steel wire coated with a metal layer. The invention also relates to a use of such a steel wire and to a method of obtaining such a steel wire.
BACKGROUND OF THE INVENTION.
[0003] Steel wires coated with a metal layer are widely known. Tonnages of steel wires have been coated with a zinc or zinc alloy layer in order to increase the corrosion resistance of steel wires. The corrosion resistance of these steel wires is largely dependent upon the thickness of the zinc layer. The thicker the zinc layer, the longer it takes before it is corroded away and the higher the corrosion resistance, and vice versa. In some cases these steel wires with a zinc layer exhibit surface defects. These surface defects may take several forms impurities, rests of lubricants such as drawing soaps remaining at the surface, hard Fe—Zn particles, burrs, rolling errors, drawing lines, asperities, and so forth. Dependent upon the eventual use of the steel wires, these surface defects may have various drawbacks. A first drawback is that the visual or esthetic aspect of the steel wire with the metal layer is bad due to inhomogenities. A second drawback is that the surface errors may lead to peaks, which may pierce through subsequently applied thin or soft layers such as a lacquer layer or a plastic layer. A third drawback is that asperities on the surface of the metal coated steel wire may cause damage to other devices, which are or which come in contact with the steel wires. Equalizing the surface of the metal layer, e.g. by etching, in order to get rid of the surface defects, unavoidably decreases the thickness of the metal layer. In case of a zinc or zinc alloy layer, this decreased thickness means a reduced corrosion resistance. In order to have a final corrosion resistance, which meets minimum requirements, an initial thicker layer must be deposited.
OBJECTS AND SUMMARY OF THE INVENTION
[0004] It is an object of the present invention to avoid the drawbacks of the prior art.
[0005] It is another object of the present invention to provide a steel wire with a metal layer and an improved visual appearance.
[0006] It is yet another object of the present invention to provide a steel wire with a visual appearance, which is stable in time.
[0007] It is also an object of the present invention to provide a steel wire with an improved visual appearance without decreasing the corrosion resistance. It is again an object of the present invention to provide a simple way of improving the visual appearance of a steel wire with a coated metal layer.
[0008] According to a first aspect of the present invention, there is provided a steel wire coated with a metal layer. The metal layer on the steel wire may be zinc or a zinc alloy, such as a zinc aluminum alloy with 1% to 10% aluminum, up to 0.2% of a Mischmetal and the remainder zinc. The metal layer on the steel wire may also be tin or a tin alloy. The steel wire and the metal layer are in a work hardened state by either rolling or drawing or both.
[0009] This means that after having been coated with a metal layer, the thus coated steel wire has been subjected to a work hardening treatment such as a rolling or a drawing treatment or both. The metal layer has a surface with roughnesses so that a surface roughness Ra of above 0.25 μm, e.g. above 0.5 μm, e.g. 1.0 μm, e.g. above 1.20 μm is reached on this surface. The terms “surface roughness Ra” refer to the arithmetical mean roughness Ra. The arithmetical mean roughness Ra can be determined sampling a section of standard length from the mean line on the roughness chart. The mean line is laid on a Cartesian coordinate system wherein the mean line runs in the direction of the X-axis and magnification is the Y-axis. The value obtained is expressed in micrometer (μm). In case of a round wire, the X-axis runs on the surface of the round wire and in the direction of the axis of the round wire. In case of a flat wire, the X-axis lies in the plane of one of the sides of the flat wire. The Y-axis is always perpendicular to the surface of the wire and to the X-axis.
[0010] The advantage of the invention is that due to the presence of the roughnesses, the visual defects on the surface of the coated steel wire are masked or have disappeared due to the roughening treatment.
[0011] Preferably the roughnesses are randomly dispersed at the surface.
[0012] Even with the relatively low degree of a surface roughness Ra ranging from 0.50 μm to 1.50 μm, the surface errors largely disappear and the visual aspect considerably improves. Moreover, an equally dull outlook is obtained, which is stable in time.
[0013] This stability is in contrast with a shiny appearance of a galvanized prior art wire just after leaving the hot dip bath. The degree of shining of a prior art wire disappears in time during use of the galvanized wire. If the surface roughness is obtained by e.g. a sand or grit blasting technique, the steel wire has the advantage of having a metal layer, which is compacted as a result of the sand or grit blasting operation.
[0014] The metal layer becomes less porous and denser. This compacted layer may result in an equal or even in an increased resistance against corrosion, despite the fact that some metal has been taken away during the sand blasting.
[0015] The steel wire may have a round cross-section, a flat cross-section with natural edges, a flat cross-section with forced edges, a rectangular cross-section, a square cross-section or any other profile, such as a I- a C-or a zeta profile. A steel wire is to be distinguished from a steel sheet or a steel plate. A steel wire has a cross-section with a width-to-thickness ratio ranging maximum up to 10/1, normally up to 8/1 or 5/1. Round wires or square wires have a width-to-thickness ratio of 1/1.
[0016] The surface roughnesses may be present on the entire surface of the 35 steel wire. However, this is not always necessary. In case of a wire with a rectangular or a square cross-section, the roughnesses may be only present on some but not all of the wire sides. It may be sufficient if the roughnesses have been provided only on the surface which is to come into contact with other devices, or only on the surface which is to be coated with a lacquer or with a thin plastic coating, or only on the surface with is exposed to visual inspection.
[0017] The steel wire may be coated with a thin plastic layer on the metal layer, such as polyamide, polyester, or polyvinyl chloride. In a preferable embodiment of the invention, the steel wire is coated with a lacquer layer on the metal layer. As the surface of the metal layer has been roughened equally without high protruding peaks, the thin plastic or lacquer layer covers completely the outer surface of the steel wire and no peaks pierce through the plastic or lacquer layer.
[0018] This is particularly true in case the plastic layer is provided by means of powder spraying, since powder spraying is more sensitive to such peaks than extrusion.
[0019] According to a second aspect of the invention, the steel wire can be used in several applications. A very useful application of the invention wire is the use as a wiper arm for wipers. The wiper arm connects the wiper blade with the wiper motor. Another use of the invention wire is as a reinforcement rail for the wiper element of a window wiper. Still another use of the invention wire is as spring wire where the roughnesses present on the surface of the coating provide an excellent reserve tank for the presence of a lubricant. Without the presence of the roughnesses, 50% to 80% of the lubricant applied to the wire falls from the wire due to gravity. In case of the invention, the roughnesses keep the lubricant on the surface of the wire. One of the advantages is that power springs made according to the invention and provided with lubricant, make less noise.
[0020] According to a third aspect of the invention, there is provided a method of smoothing away surface errors on an elongated steel element. The method comprises the following steps:
a) providing a steel wire; b) coating the steel wire with a metal layer resulting in a coated steel wire; this coated steel wire is drawn or rolled; c) applying a surface treatment to the coated steel wire in order to smoothen away surface errors, said surface treatment resulting at least partially in a surface roughness Ra above 0.5 μm.
[0024] Preferably, the surface treatment comprises sand or grit blasting since this results in a randomly dispersed pattern of the roughnesses.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The invention will now be described into more detail with reference to the accompanying drawings wherein:
[0026] FIG. 1 is a cross-section of a first embodiment of an invention wire;
[0027] FIG. 2 ( a ) shows a side view of a prior art wire and FIG. 2 ( b ) shows a side view of an invention wire;
[0028] FIG. 3 is a cross-section of a second embodiment of an invention wire;
[0029] FIG. 4 illustrates a use of an invention wire as a wiper arm; and
[0030] FIG. 5 illustrates a use of an invention wire as a reinforcement rail for a window wiper element.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIG. 1 is a cross-section of a first embodiment of an invention wire 10 . The wire 10 is a flat high-carbon steel wire. Wire 10 has a steel core 12 and a layer 14 of a zinc aluminum alloy with about 5% aluminum and up to 0.2% of a Mischmetal such as lanthanum or 35 cerium. The wire 10 has been sand blasted so that its surface exhibits an equally dull outlook with randomly dispersed small roughnesses 16 .
[0032] A steel wire 10 according to the invention may be manufactured as follows. Starting product is a high-carbon steel wire rod with e.g. following composition: a carbon content ranging from 0.20 to 0.50%, a manganese content ranging from 0.40 to 0.90%, a silicon content ranging from 0.05 to 0.40%, sulfur and phosphor contents being below 0.05%. The wire rod is drawn down to an intermediate diameter. The drawn and round high-carbon steel wire is subjected to a hot dip operation in order to coat the round steel wire with a metal layer of a zinc aluminum alloy. The coated round steel wire is then subjected to a rolling operation in order to obtain a rolled and coated steel wire with a flat cross-section, i.e. a steel wire with two flat sides and natural edges (i.e. rounded edges, in contrast with a rectangular wire with four flat sides). As a matter of example, the coated steel wire may have following dimensions (width×thickness) : −7.0 mm×2.2 mm −8.0 mm×3.0 mm 20−9.0 mm×3.0 mm −9.0 mm×3.3 mm −9.0 mm×3.46 mm −9.0 mm×4.0 mm −12.0 mm×4.0 mm Reference is now made to FIG. 2 ( a ). The rolled and coated flat steel wire 10 may exhibit some surface defects: the unevenness of the rolls is directly translated into longitudinal grooves 18 extending along the steel wire 10 , hard particles 20 such as Fe—Zn particles, which are not completely solved in the zinc aluminum matrix, may be visible. Other surface defects (not shown) may be burrs, lubricant rests, lumps because of disturbances in prior hot dip coating operation. . . . The coated and rolled steel wire is then subjected to a sand or grit blasting operation, which results in invention wire 10 , with randomly dispersed roughnesses 16 as illustrated in FIG. 2 ( b ).
[0033] The blasting operation may be carried out in a dry way or in a wet way. The wet way is to be preferred because of a lower exploitation cost, a better polishing effect and a better controllability. Wet blasting may comprise three subsequent steps: a blasting phase, a rinsing phase and a drying phase. During the blasting phase, an abrasive material such as ceramic particles, steel grit or glass particles is sprayed on the coated and rolled steel wire. The form and the size of the abrasive material determine the pattern to be obtained on the wire surface. The abrasive material may be captured, filtered and recuperated in the system by means of a central pump. The abrasive material can be aluminum oxide, zirconium oxide or chromium nickel steel. The abrasive material can be in the form of balls with a diameter ranging up to 500 μm.
[0034] In experiments carried out, three coated and rolled steel wires had following features before sand blasting: −gloss (60°):166-170-roughness Ra: 0.07-0.04-0.12 After sand blasting twice the three steel wires with a mixture of glass grits (80-112) and ceramic grits (Zr 097-B120), under a pressure of 3.2 bar and at a distance of 20 cm, the resulting steel wire had following features:
−gloss (60°):13 25-roughness Ra:1.67-1.23-1.58.
[0035] Salt spray tests have been carried out on the original coated and rolled steel wires and on the sand blast steel wires. The following table mentions the number of hours before DBR—dark brown rust—appears on the surface.
TABLE Spots of Locations DBR of DBR DBR (5%) Original 912 1032 1176 1368 1560 Sand blast 1248 1512 1560 912 1104 1248
[0036] The table clearly shows that there is not a substantial decrease in corrosion resistance despite the disappearance of some coating 5 material due to sand blasting.
[0037] The roughnesses may be realized on the surface of the coated and rolled steel wire in still other ways such as by means of brushes out of hard metal. The use of brushes, however, does not result in a randomly dispersed pattern of roughnesses. Brushes create multiple lines on the surface.
[0038] FIG. 3 gives a cross-section of a second embodiment of an invention wire 10 . The wire 10 has a rectangular cross-section. The wire 10 has a steel core 12 , a zinc metal layer 14 which has been sand blasted so that roughnesses 16 are present at the surface of metal layer 14 . Above the metal layer 14 is a thin lacquer layer 22 . Since the roughnesses are all controlled and asperities have been avoided, the lacquer layer 22 completely covers the surface of the metal layer 14 without any peaks piercing through the thin lacquer layer. As a matter of example, the thickness of the lacquer layer ranges from 10 μm to 50 μm, preferably from 20 μm to 40 μm.
[0039] FIG. 4 illustrates an appropriate and suitable use of an invention wire 10 . The invention wire 10 functions as wiper arm between a wiper motor (not shown) and the wiping element 24 , which rests on the window. The wiper arm performs a to and fro oscillating movement.
[0040] FIG. 5 shows the cross-section of a wiping element 24 . The wiping element is made of blade rubber 26 and has various slots 28 . Invention wires 10 function as reinforcement rails and are located in the upper slots 28 .
[0041] While this invention has been described as having a preferred design, it is understood that it is capable of further modifications, and uses and/or adaptations of the invention and following in general the principle of the invention and including such departures from the present disclosure as come within the known or customary practice in the art to which the invention pertains, and as may be applied to the central features hereinbefore set forth, and fall within the scope of the invention or limits of the claims appended hereto. | Steel wire is coated with a metal layer such that the metal layer has a surface with roughnesses. A surface roughness Ra of above 0.25 μm is reached. Preferably, the roughnesses are randomly dispersed at the surface. The result is an improved visual aspect and an increased resistance against corrosion. | 8 |
TECHNICAL FIELD
The invention relates to an automatic plant for pressing and unloading articles of clothing, specifically trousers.
More precisely, the present invention relates to an automatic plant which enables automatic pressing/ironing by the application of air and/or steam to a plurality of articles, such as trousers, continuously loaded on to the machine itself, and which then enables the trousers to be unloaded so that they can pass on to further operations.
The invention can be mainly applied in the field of industrial ironing-pressing machines.
BACKGROUND ART
The prior art teaches basically two types of machines for trouser pressing.
A first type of machine comprises a pair of hot plates between which the trousers to be pressed are inserted.
The pressing operation is carried out by combined application of pressure and heat.
A second type of ironing machine (see for instance DE-A-4,415,002) is of the type generally known as blown or ventilated ironing, or "Topper", and comprises a pair of movable shaped elements which translate following an electropneumatic command, and block, keep blocked and subsequently unblock within the belt area, a trouser positioned in correspondence of these elements by an operator.
This machine further comprises two pairs of plates, which are simultaneously movable in a vertical direction, each pair of plates fastening a lower end of a trouser by means of an elecotropneumatic command.
During operation, an operator first fixes the upper part of the trouser by using said shaped elements, thereafter he uses the plate pairs to fix the bottom ends of the trouser.
Subsequently the pairs of plates are vertically moved in such a way as to keep the trouser stretched. Then a jet of steam and/or hot air is directed into the trousers through the belt zone, which zone is kept open by the shaped elements. The inlet of hot air and/or steam is kept up for a determined time, directed by the operator, which time will be sufficient to press the trousers.
Finally, the operator switches off the electropneumatic commands, manually unloads the trouser, places it on a specially-provided working surface and loads a next pair of trousers.
Generally, the pressing times are between 15-18 seconds, which leads to an average production of about 800 trousers per day for each machine.
The above-described machines are normally utilised in pairs, with the aim of rationalising the pressing times and obtaining higher production.
In this case, a single operator acts on both machines, which work at staggered rhythms; for example, while one machine is pressing, the operator can load and/or unload the other machine.
A working cycle of this kind enables the production of about 1500-1700 pressed trousers per day per operator, based on the average pressing time of 15 seconds per trouser.
For obvious reasons connected with production, machines of this type are programmed to carry out the pressing in the shortest time possible, compatibly with the obtaining of a given quality of pressing. It has been found that about 15 seconds does not provide a high-quality pressing, which is obtained only with times higher than 22 seconds per trouser; however, such long times are incompatible with the production rhythms required by modern industrial pressing/ironing companies.
Further, each pair of the above-described pressing machines requires the presence of a fixed operator, leading to considerable production costs.
DE-A-1,802,225 discloses an automatic pressing/ironing machine constituted by a rotating carousel on which is mounted a plurality of stretched dummies suitable for supporting corresponding shaped articles of clothing such as skirts, dresses and the like. Moreover, a suitable device is provided in order to introduce steam, and successively hot air, into said dummies while the dummies are stopped at predetermined working stations.
FR-A-1,158,733 discloses an automatic plant which is constituted by a rotating carousel composed by a plurality of dummies which are intermittenly moved passing through predetermined stations where steam and hot air are supplied.
GB-A-1,409,244 discloses an automatic plant that is provided with a plurality of bucks on which the garments are mounted and indexed to and from a number of stations at which different operations are performed.
The automatic plant also presents an automatic unloading device which is constituted by a suitable arm, operated by a piston and cylinder arrangement, the free end of said arm being provided with a nose so as it can engage the hanger placed inside of the buck.
DESCRIPTION OF THE INVENTION
The present invention aims to provide a solution to the above-described problems by providing an automatic pressing machine for ironing and pressing of trousers which allows high production levels to be achieved, as well as reducing the number of operators dedicated to the machines, and thus also reducing production costs.
This result is obtained with an automatic plant for pressing trousers having the features described in the main claim.
The dependent claims describe further advantageous embodiments of the invention.
The automatic machine according to the present invention comprises a rotating carousel on which are located a plurality of machines for pressing trousers by means of the application of steam and/or hot air, said machines being arranged on the carousel at predetermined and, advantageously, equal angular distances.
The plant comprises a first loading station, at which an operator loads a trouser on the machine which is temporarily present at said first station.
During the course of the carousel's motion, the pressing machine which is coming out of the first loading station carries out the pressing operation in a conventional way, for a predetermined time span.
The machine then arrives at a second station, for unloading, at which a preferably automatic unloading device is present.
This unloading device is formed by a suction head which is automatically disposed at the position of the trouser to be unloaded at the instant when the trouser unblocking elements are opened.
Consequently, the trouser is loaded by the suction head, which distances the trouser from the machine and deposits it on a plane which is advantageously constituted by a special conveyor.
In the meantime, the machine, which has been unloaded of the trouser, is brought back to the first loading station to start a new cycle.
A careful choice of carousel rotation times leads to obtaining a plurality of advantages, thus attaining the aims of the invention.
The whole plant, composed of a number of machines, can be managed by a single operator whose only task is to load the trousers on the machine, as the unloading is completely automatic.
Further, high productivity and relatively long pressing times can be obtained, giving a high-quality finished product.
ILLUSTRATION OF DRAWINGS
Further features and advantages of the invention will better emerge from the detailed description that follows, provided as a non-limiting example together with the annexed drawings, in which:
FIG. 1 schematically shows the work process of a steam and/or hot air machine for trouser pressing of a conventional type;
FIG. 2 is a schematic representation of a trouser pressing plant according to the present invention, in this case provided with four pressing machines of the type illustrated in FIG. 1.
DESCRIPTION OF A FORM OF EMBODIMENT.
In FIG. 1, a conventional machine for steam and/or hot air pressing of trousers comprises a pair of shaped elements 10, 11, which are simultaneously movable by means of a special electropneumatic command, from a first position (shown in broken lines) in which the elements 10, 11 are drawn near, and a second position (shown in continuous lines) in which the elements 10, 11 are driven away.
The movements carried out by the elements 10, 11 are indicated in FIG. 1 by means of arrows A, which are in fact two endrun positions, at the first of which a trouser 14 can be inserted from below externally of the elements 10, 11, while at the second of which the trouser is gripped by the dividing force of the elements 10, 11 themselves.
The machine further comprises two pairs of plates 12, 13, which are parallel (only the first of the plates is visible in FIG. 1).
Each of the pair of plates 12, 13, is arranged such that a front plate can be drawn near and driven away from a back plate, with the aim of enabling an end of a trouser 14 to be inserted and subsequently blocked there by means of an electropneumatic command.
Further, the two pairs of plates 12, 13, are provided with a vertical raising and lowering movement, also controllable by means of an electropneumatic command, with the aim of keeping the trouser vertically stretched once its ends have been respectively inserted and blocked between the pairs of plates 12, 13.
The vertical raising and lowering movements of the plates 12, 13, is indicated in FIG. 1 by arrows B.
Finally, the machine comprises a device 15 for introducing into the trouser 14, when blocked by the elements 10, 11 and the plates 12, 13, a jet of steam and,or hot air at predetermined temperatures and pressures, for a period of time which is also predetermined and sufficient for obtaining a pressing of the material constituting the trouser 14.
A machine of this type is well known in the prior art and is not part of the present invention.
In FIG. 2, a plant 20 for automatic steam and/or hot pressing of trousers comprises a rotating carousel constituted by a circular metal frame 21 for supporting a plurality of pressing machines 22, 23, 24, 25 of the type illustrated in FIG. 1 and described hereinabove, said machines being individually connected to a centralised system (not illustrated) for steam production, or hot or compressed air production.
The circular metal frame 21 is connected to special means (not shown in the figures) for rotating the frame 21 itself about its axis 0.
For this purpose, for example, the frame 21 can be arranged on special turntables or bearings which are connected, for example, by a belt, to a driving device constituted by an electric step motor and a possible gear reducer; an electronic control device drives the frame 21 in rotation at an exactly-predetermined angular speed in the direction indicated by arrow S in the figure.
We consider now the machine 21, which placed at the loading station of the trousers 26.
An operator, acting at said loading station, loads a trouser 26 on to the machine 22 during the rotation movement of frame 21 about axis 0, following the same modalities as described with reference to FIG. 1.
Once the loading has been carried out, the steam and/or hot air is immediately injected into the inner part of trouser 26, and trouser 26 is subjected thereto for a predetermined period of time, for example 24 seconds, until it reaches the unloading position as indicated in FIG. 2 by the position of the machine 25.
At this point the steam and/or hot air is shut off and the trouser 26 is removed from the machine by a second operator, or, advantageously, by means of an automatic device 30 which will be described in more detail hereinbelow.
The above-described process is continuously repeated for each machine on the frame 21. In this context it is worthwhile noting that FIG. 2 represents a plant equipped with four machines 22, 23, 24, 25; however, the number of machines does not constitute a limitation of the present invention, which is applicable to any number of machines.
Also noteworthy is the fact that the invention is not limited to a plant assembled on a circular frame; preferred embodiments include those having single machines mounted on movable supports moving along tracks following a predetermined route, not necessarily circular.
According to the invention, the plant 20 is provided with an automatic unloading device 30 for the pressed trousers, arranged at an unloading station identified in FIG. 2 as the position at which the machine 25 is temporarily halted.
The device 30 is essentially constituted by an arm 31 oscillating between two endrun positions indicated respectively in continuous and broken lines, the oscillating motion being produced by a special motor (not shown in the figure) vertically about an axis H and in the direction indicated by arrow F.
The free end of the arm 31 is provided with a suction head 32 connected to means for creating suction, for example a vacuum pump, controllable by means of the electronic plant command device 20.
In operation, the arm 31 is moved in such a way that the head 32 comes into the vicinity of the pressed trouser 27 at the moment of passage of the machine 25 into the unloading station.
The suction head 32 is activated coordinatedly with the unblocking of the trouser by the plates and the shaped elements on the machine 25, and the trouser is loaded by the suction head 32 itself; the oscillating arm is thus caused to oscillate towards the second endrun position and, having reached this position, the aspiration is interrupted.
Consequently, the trouser 27 falls on a surface 40 which is advantageously constituted by a conveyor which transports the trouser towards other working stations, for example a stocking station.
The oscillating arm then oscillates once more, collecting the next pressed trouser produced by the rotary movement of the frame 21 at the unloading station.
The main electronic command device obviously coordinates and synchronises the respective rotation speeds of the frame 21 and the arm 31 oscillation.
A plant 20 of the above-described type affords a plurality of advantages.
Indeed, tests carried out by the applicant have shown that it is possible, for example with a plant constituted by four machines such as the above-described, to manage the whole plant with a single operator for loading trousers, thus reducing the overall costs.
Further, in a plant of this type the pressing times can be kept relatively high, for example 24 seconds between loading and unloading, thus obtaining a very high pressing quality while maintaining daily productivity at about 3200 trousers. This number substantially corresponds to the same number of trousers obtainable with four traditional machines, for which two operators are necessary and which offers a pressing time of only 15 seconds.
If pressing quality is somewhat sacrificed, bringing down pressing times to 15 seconds, and consequently increasing the speed of the carousel, the plant of the invention offers very high production rates, unthinkable with traditional processes. | An automatic plant (20) for pressing and unloading trousers (26, 27) using a plurality of machines (22, 23, 24, 25) for pressing said trousers by means of steam and/or hot air, each of which machines being provided with first means (10, 11) for blocking and unblocking an upper end of an article of clothing, and second means (12, 13) for blocking and unblocking lower ends of a same article of clothing, as well as with third means (15) for expelling and directing steam and/or hot air internally of said trousers when they are blocked by said first and second means. Said machines (22, 23, 24, 25) are mounted on a movable carousel continuously moving along a predetermined route, in such a way that said trousers (26, 27) are subjected to a pressing operation by means of steam and/or hot air for the whole period of time comprised from loading to the unloading operations of said trousers. | 3 |
RELATED APPLICATIONS
This application claims priority from U.S. Patent Application Ser. No. 62/052,134 entitled “Padlock Retaining Device,” filed Sep. 18, 2014, the entirety of which is incorporated herein by reference.
BACKGROUND
Roll-up doors are used for a wide variety of applications. For example, roll-up doors are frequently used to secure the interiors of enclosed storage areas, such as the areas within storage units in a commercial self-storage rental facility.
When used to secure the interior of enclosed storage areas, the roll-up doors are typically made from steel and the doors are provided with a locking apparatus. In the most common applications, such locking apparatuses comprise at least one slidable bolt attached to the door or a strong slide rail. FIG. 1 illustrates such a locking apparatus. The slidable bolt can be alternatively (1) slid in one direction along the slide rail to a “latched position,” wherein the bolt is caused to protrude into a strike plate mounted on the door frame (to prevent the door from traveling upward) and (2) slid in the opposite direction along the slide rail to an “unlatched position,” wherein the bolt is retracted out of the strike plate (to allow the door to again freely travel upward).
Typically, the slide rail and the slidable bolt each have a padlock retainer portion defining a locking through-hole which is sized and dimensioned to accept a padlock shackle (curved portion). The holes in the padlock retainer portions are located so that, when the bolt is slid to the latched position, the holes are aligned with one another such that a padlock shackle can be placed and secured within both holes to lock the bolt within the latched position (as illustrated in FIG. 2 ).
It is also common that both the slide rail and the bolt have an auxiliary hole—termed a manager's overlock hole—which can be used by the manager of a facility employing the roll-up door to lock the door in the latched position (for example, if rent is overdue). The manager's overlock hole can also be used to retain the padlock on the roll-up door when the bolt is in the unlatched position. This design seems to provide the user with a convenient place to store the padlock when it is not being used, such as immediately after the user unlocks the padlock and slides the bolt to the unlatched position in preparation for opening the roll-up door. The problem with this design, however, is that, if the user forgets to remove the padlock from the manager's overlock hole before the roll-up door is opened, the padlock will be carried upwards as the roll-up door is opened and strike the upper horizontal portion of the door frame. This illustrated in FIG. 3 . Because roll-up doors are typically heavy and carry considerable momentum, such striking of the door frame can cause significant damage to the door frame, to the latch assembly and/or to the roll-up door. If the door frame is made of steel or other heavy material, the striking of the door frame with the padlock can rip the latch assembly off of the roll-up door.
Accordingly, there is a need for a padlock retaining device that addresses the problem often encountered with the use of roll-up doors.
SUMMARY OF THE INVENTION
The invention satisfies this need. The invention is a unique padlock retaining device. The padlock retaining device comprises: a) a stand-alone body, separate from any locking device or latching device, the body having one or more body attachment facilitators and b) a lock containment section attached to and extending away from the body for accepting and retaining an open padlock.
The invention is also a method of employing the padlock retaining device to prevent damage caused by inadvertently opening a roll-up door with a padlock still attached to the roll-up door.
DRAWINGS
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description, appended claims, and accompanying drawings where:
FIG. 1 is a sketch illustrating a slide lock of the prior art;
FIG. 2 is a sketch illustrating a slide lock attached to a roll up door disposed within a door frame, wherein a padlock has been operably placed on the slide lock to secure the slide lock in a latched position;
FIG. 3 is a sketch illustrating the roll up door of FIG. 2 wherein the padlock has been opened and hung loosely on the slide lock and wherein the roll up door has been rolled up to inadvertently cause the padlock to strike the top of the door frame;
FIG. 4 is a perspective view of a padlock retaining device having features of the invention;
FIG. 5 is a front view of the padlock retaining device illustrated in FIG. 4 ;
FIG. 6 is a side view of the padlock retaining device illustrated in FIG. 4 ;
FIG. 7 is a top view of the padlock retaining device illustrated in FIG. 4 ; and
FIG. 8 is a sketch illustrating a slide lock attached to a roll up door disposed within a door frame, and a padlock opened and hung loosely on a padlock retaining device having features of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The following discussion describes in detail one embodiment of the invention and several variations of that embodiment. This discussion should not be construed, however, as limiting the invention to those particular embodiments. Practitioners skilled in the art will recognize numerous other embodiments as well.
DEFINITIONS
As used herein, the following terms and variations thereof have the meanings given below, unless a different meaning is clearly intended by the context in which such term is used.
The terms “a,” “an,” and “the” and similar referents used herein are to be construed to cover both the singular and the plural unless their usage in context indicates otherwise.
As used in this disclosure, the term “comprise” and variations of the term, such as “comprising” and “comprises,” are not intended to exclude other additives, components, integers, ingredients or steps.
The Invention
In one aspect, the invention is a padlock retaining device 10 built specifically to hold a padlock 12 in a convenient location adjacent to a roll-up door 14 , not on the roll-up door 14 itself. FIGS. 4-7 illustrate one embodiment of the invention.
The padlock retaining device 10 comprises a body 16 , one or more body attachment facilitators 18 , and a lock containment section 20 . The padlock retaining device 10 can be any size and dimension, and made from any material, including plastic, wood or metal. In the embodiment illustrated in FIGS. 4-7 , the padlock retaining device 10 can be 2 and ¾ inches tall, 1 and ⅞ inches wide and preferably can be made from a single plate of steel.
The body 16 can be any shape and dimension, but preferably the body 16 is planar. In the embodiment illustrated in FIGS. 4-7 , the body 16 is in the shape of a padlock. In the embodiment illustrated in FIGS. 4-7 , the padlock retaining device 10 has two body attachment facilitators 18 which be used to attach the padlock retaining device 10 to a wall surface 36 adjacent a roll-up door 14 . Optionally, the two body attachment facilitators 18 can be fastener holes, and the padlock retaining device 10 can be attached to the wall surface 36 using any type of fastener, for example, stainless steel fasteners, screws or rivets depending on the application.
The lock containment section 20 is configured to accept and retain a padlock shackle 22 . The lock containment section 20 is coupled to the body 16 at a sufficient angle to accept and retain a padlock shackle 22 . The lock containment section 20 can be made from any material, including plastic, wood or metal, but preferably it is made from steel. The lock containment section 20 can be any size and dimension, but preferably it is about ⅞ inches long.
Optionally, the padlock retaining device 10 can be made from a single plate of steel, as shown in the embodiment illustrated in FIGS. 4-7 . Because the padlock retaining device 10 can be made from a single plate of steel, the lock containment section 20 is a portion of the padlock retaining device 10 that is bent away from the body 16 . Preferably the lock containment section 20 is bent away from the body 16 at a 90 degree angle with respect to the body 16 .
The lock containment section 20 can also have a padlock shackle retaining hole 26 defined therein. The padlock shackle retaining hole 26 is sized and dimensioned to accept and retain a padlock shackle 22 . The padlock shackle 22 is inserted through the padlock shackle retaining hole 26 such that the padlock 12 is now retained by the padlock retaining device 10 .
In another aspect, the invention is a method of employing the padlock retaining device 10 to prevent damage caused by inadvertently opening a roll-up door 14 with a padlock 12 still attached to the roll-up door 14 .
The padlock retaining device 10 is especially useful for a roll-up door 14 comprising a locking apparatus 32 having:
a slidable bolt 34 attached to the door on a slide rail, wherein the bolt 34 can be alternatively (1) slid in one direction along the slide rail to a “latched position,” wherein the bolt 34 is caused to protrude into a strike plate mounted on the door frame (to prevent the roll-up door 14 from travelling upward) and (2) slid in the opposite direction along the slide rail to an “unlatched position,” wherein the bolt 34 is retracted out of the strike plate (to allow the roll-up door 14 to again freely travel upward); padlock retainer portions defined within both the slide rail and the bolt 34 to provide a locking through-hole which is sized and dimensioned to accept a padlock shackle 22 , the holes in the padlock retainer portions being located so that, when the bolt 34 is slid to the latched position, the holes are aligned with one another such that a padlock shackle 22 can be placed and secured within both holes to lock the bolt 34 within the latched position; and a manager's overlock hole defined in both the slide rail and the bolt 34 which is operatively configured to retain the padlock 12 on the roll-up door when the bolt 34 is in the unlatched position.
As discussed above, many users secure the padlock 12 to the manager's overlock hole (not shown) after they have removed the padlock 12 from the roll-up door 14 , but prior to actually opening the roll-up door 14 . Then the roll-up door 14 is moved upward to an open position, which causes the locking apparatus 32 to strike the upper portion of the door frame 38 .
In the method, the padlock retaining device 10 is attached to a wall surface 36 —typically a vertical wall surface—separate from the roll-up door 14 for which a padlock 12 is used to secure the roll-up door 14 in the latched position. Then the padlock 12 is retained on the padlock retaining device 10 when the padlock 12 is not in use by disposing the padlock shackle 22 into the padlock shackle retaining hole 26 —as illustrated in FIG. 8 .
The method of employing the padlock retaining device 10 comprises the steps of providing the padlock retaining device 10 , attaching the padlock retaining device 10 to a wall surface 36 separate from the roll-up door 14 by the one or more body attachment facilitators 18 , disposing the padlock shackle 22 into the lock containment section 20 , and retaining the padlock 12 on the padlock retaining device 10 when the padlock 12 is not in use.
The method effectively prevents damage to the roll-up door 14 , the locking apparatus 32 and/or the door frame 38 by inadvertently rolling the roll-up door 14 upwards while the padlock 12 is attached in the auxiliary manager's overlock hole of the locking apparatus 32 —thereby causing the locking apparatus 32 to strike the upper portion of the door frame 38 . | A padlock retaining device has: a) a stand-alone body, separate from any locking device or latching device, the body having one or more body attachment facilitators and b) a lock containment section attached to and extending away from the body for accepting and retaining an open padlock. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/632,211 filed Nov. 29, 2004. This application is a Continuation-in-Part Application of US Non-Provisional Patent Application Ser. No. 2006/0112513 A1 filed Nov. 29, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to cleaning systems. More specifically, the present invention is drawn to a cleaning or surface-treating system in which pressurized water, water/chemical mixtures or surface treating fluids are supplied to a sonic vibrating cleaning pad. The cleaning pad can travel in both the linear and oscillating motions.
[0004] 2. Description of the Related Art
[0005] Homeowners and small commercial establishments constantly search for affordable, portable, efficient cleaning devices that are also versatile. Surfaces around the home or office such as floors, decks, walls, driveways, carpets, upholstery, etc. require cleaning or treating on a periodic basis. More often than not, the home or business owner will attempt to clean or treat these surfaces instead of hiring professional cleaners. The most popular cleaning devices, as shown in the related art, rely on pressurized spray nozzles to accomplish the above noted functions. While somewhat effective, the pressurized nozzle units sill leave a lot to be desired, especially when used to clean heavy, layered grime and dirt from surfaces. The art would certainly welcome a cleaning system that could handle a variety of cleaning situations in an effective and efficient manner and yet have the simplicity to be operated by everyone.
[0006] None of the inventions and patents identified in the previous IDS, taken either singly or in combination, is seen to describe the cleaning system as will subsequently be described and claimed in the instant invention.
SUMMARY OF THE INVENTION
[0007] The indoor/outdoor cleaning system of the present invention comprises a portable, pressurized housing for containing cleaning or treating fluids (water, chemicals and mixtures thereof). The housing is pressurized for reasons that will be explained below. Multiple hoses connect the interior of the housing with a cleaning wand. The wand includes a handle, a hollow trunk portion and a cleaning head. The multiple hoses have outlets in the cleaning head for feeding water and cleaning chemicals thereto. The outlets open adjacent a cleaning pad, which pad is attached to the cleaning head via a mechanism that allows the pad to vibrate at sonic frequency. An accessory (brush, sponge, sanding pad, buffing pad, etc.) is removably attached to the pad and will be selected based on the type of surface to be cleaned or treated. A suction conduit, disposed in the cleaning head, functions to draw used fluids away from the surface for safe disposal thereof.
[0008] Accordingly, the invention presents a cleaning system, which system is capable of effectively cleaning and/or treating almost any surface. The system is relatively compact and portable, which permits the system to be utilized by homeowners and small business establishments. Utilization of sonic vibration technology permits the cleaning or treating fluids to be applied to the desired surface area with minimum spillage and waste. The cleaning pad unit of the device can have both a linear motion and an oscillatory motion. The linear motion is both a back and forth motion where an oscillating motion can be activated as well in order to clean between spaces of the tiles, woods or any other material where dirt can easily hide. The back and forth motion of the device can be adjusted by the operator by making the accessory travel in greater distance between each stroke or shorter distance to focus on a particular area. Also, the oscillating motion of the device can provide for a rocking motion or seesaw motion to scrub or remove dirt where gaps exist between materials.
[0009] The invention provides for improved elements and arrangement thereof for the purposes described which are inexpensive, dependable and fully effective in accomplishing their intended purposes.
[0010] A clear understanding of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is an environmental, perspective view of an indoor/outdoor cleaning system according to the present invention.
[0012] FIG. 2 is a perspective view of a cleaning wand of an indoor/outdoor cleaning system according to the present invention.
[0013] FIG. 3 is a partial view showing a cleaning head of an indoor/outdoor cleaning system according to the present invention.
[0014] FIG. 4 is a plan view of an LCD screen of an indoor/outdoor cleaning system according to the present invention.
[0015] FIG. 5 is a perspective view of a cleaning caddy of an indoor/outdoor cleaning system according to the present invention.
[0016] FIG. 6 is a perspective view of a second embodiment of a cleaning was of an indoor/outdoor cleaning system according to the present invention.
[0017] FIG. 7 is a partial side view showing an alternative embodiment of the cleaning pad unit of an indoor/outdoor cleaning system according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] Attention is first directed to FIGS. 1 and 2 wherein the cleaning system of the present invention is generally indicated at 10 . System 10 includes a cleaning wand 12 having a handle 14 attached at an upper end and a cleaning head 16 attached at a lower end. Pressurized housings 18 , 18 a respectively contain fluids to be supplied to cleaning head 16 via hoses 20 and 20 a . Power cord 22 extends from handle 14 for connection to a source of electrical power E. A suction hose 24 is in fluid communication with cleaning head 16 . As best seen in FIG. 2 , handle 14 is pivotally attached to wand 12 at 14 a . Wand 12 is pivotally attached to cleaning head 16 at 12 a . A multi-function operating switch 26 and a LCD monitor 28 (both of whose functions are explained below) are mounted on handle 14 .
[0019] As best illustrated in FIG. 3 , wand 12 and head 16 have hollow interiors for receiving hoses 20 , 20 a and power cord 22 . Hose 20 a has an outlet 30 at base 16 a of cleaning head 16 . A cleaning pad unit 34 is disposed adjacent base 16 a and is spaced therefrom. A cleaning pad unit 34 has a hollow interior and a perforated base 34 a . Hose 20 has an outlet 32 that opens into the interior of the cleaning pad unit 34 . An electronically powered motor 36 is positioned in head 16 and is connected to power cord 22 . Motor 36 functions to produce vibratory motion in shaft 36 a , which shaft 36 a is connected to cleaning pad unit 34 . The motor 36 is designed to produce vibratory motion in the range of 40,000-15,000 strokes per minute. A replacable accessory 38 is removably mounted on the cleaning pad unit 34 . As noted above, accessory 38 will be selected based on the type of surface that is to be cleaned or treated. The removable accessory 38 can be a brush head, mop head, scrubber, or any type of good used for cleaning surfaces. A suction port 40 is provided to remove the used fluids from the treated surfaces. Suction port 40 is connected to suction hose 24 . LCD readout device 28 ( FIG. 4 ) is mounted on the handle and is programmed to monitor selected functions. The functions shown are merely examples of the many functions that may be monitored.
[0020] Referring to FIG. 3 , the cleaning pad unit 34 travels in a linear motion when the cleaning device is activated for vibratory motion. The linear motion is a back and forth motion 12 a as shown in FIG. 2 . A stroke is defined by the distance the cleaning pad unit 34 can travel within the wand 12 . One stroke can be up to 6 inches from the back end to the front end of the base 16 a . The user can adjust a stroke where the cleaning pad unit 34 can travel less than 6 inches or more than 6 inches. The stroke can be adjusted to be less than a ¼ of an inch. The user can use a user interface to adjust the stroke to travel a desired distance to cover a certain surface area, which a user interface is not shown in the embodiment, but can be employed to change the distance at which the cleaning pad unit 34 can travel for each stroke. The user interface is connected to a control processing unit (not shown) which is then connected to the cleaning pad unit 34 . The user can desire to maintain the stroking distance to be the same throughout the entire cleaning process or he can change the stroking distance.
[0021] The importance behind changing the stroking distance to have the replaceable accessory 38 to concentrate on the surface area at which the user desired to be scrubbed, wiped, or cleaned. If the stroking distance of the cleaning pad unit 34 covers a small area such as ¼ of an inch, then the replaceable accessory 38 may focus on a particular area to remove a stain or hardened dirt. If the stroking distance of the cleaning pad unit 34 is greater than 6 inches, then cleaning pad unit will clean more of the surface area with each stroke and it would not be as focus covering a greater area with each stroke.
[0022] To facilitate the cleaning or treating operation and to enhance portability, a caddy 50 ( FIG. 5 ) is provided to transport housings 52 . Housings 52 are adapted to contain all fluids that are utilized in a cleaning or treating process. The housings are provided with pumps 54 for pressurizing the fluids and supplying said fluids to the wand via hoses 20 , 20 a . A pump also induces suction in suction hose 24 for evacuating the used fluids to the wand via hoses 20 , 20 a . A pump also induces suction in suction hose 24 for evacuating the used fluids and disposing of the same. A heating coil 56 is utilized to hear the cleaning or treating fluids if desired.
[0023] In a second embodiment, as illustrated in FIG. 6 , the wand 12 is self-contained in that a rechargeable battery 60 and pump 62 (both shown in phantom lines) are encased in wand 12 . The battery provides power to motor 36 while the pump extracts fluids from housing 18 . It should also be noted that housing 18 can take on the form of a canister mounted to the exterior of the wand.
[0024] In use, manipulation of multi-function switch 26 will activate a pump(s) for supplying fluids (for example cleaning fluid and water) through hoses 18 , 18 a . Switch 26 also functions to operate motor 36 to vibrate the accessory 38 . Cleaning fluid and water will exit the cleaning head whereby the cleaning pad unit 34 employs vibratory motion to clean the desired surface. A suction pump can be activated to withdraw the used fluids away form the surface for safe disposal.
[0025] FIG. 7 renders an alternative embodiment of the cleaning pad unit 34 having electromagnets which provides the pad or removable accessory 63 with oscillatory motion. The cleaning pad units include a motor 60 , shaft 61 , frame 72 . There can be one motor in the center of the frame 72 , or there can be two motors 60 on each end of the frame 71 . There can be more motors 60 in order to provide the cleaning pad unit 34 with more power to scrub the dirt from surfaces.
[0026] Furthermore, FIG. 7 shows the cleaning pad unit 34 having a pad (or removable accessory) 63 , pivot point 64 , coupler 65 . The motor 60 is connected to the shaft 61 which the shaft 61 is attached to a guide 71 and linear member 74 . Once again, if there a plurality of motors and shafts, then there will be a plurality of guides 71 . There is a second guide 67 on the linear member 74 connected to a resistance member 66 to prevent the structure moving in the linear motion from colliding with the frame 72 . On the frame 72 , there are about two electromagnets 69 a , 70 a connected on each end of the frame 72 , and two metal plates 69 b , 70 b are connected on the oscillating member 73 . The structural set up for FIG. 7 permits a rocking motion to take place for the oscillating member 73 . This rocking motion is like a seesaw motion or oscillating motion for the oscillation member 73 which is connected to the coupler 65 and that oscillating motion is translated onto the pad or removable accessory 63 . The electromagnets 69 a , 70 a are facing the metal plates 69 b , 70 b , respectively. Elastic members 68 a , 68 b are sandwiched and connected between the oscillating member 73 and linear member 74 , so that way both members would not collide with each other preventing damage between the oscillating member 73 and linear member 74 .
[0027] Through the user interface, a person can activate the electromagnets 69 a , 70 a where both of them may have current running through at the same time to produce an up and down motion. When the electromagnets 69 a , 70 a are activated current is flowing through it to produce a magnetic field forcing the metal plates 69 b , 70 b to move towards the electromagnets 69 a , 70 a where the metals 69 b , 70 b would be attracted to the electromagnets 69 a , 70 a . By producing an oscillating motion or seesaw motion, a person can activate one electromagnet 69 a while the other electromagnet 70 a is deactivated to bring one end of the oscillating member 74 down and the other end up. And then, the electromagnet 69 a is deactivated while the other electromagnet 70 a is activated producing an oscillatory motion like a seesaw or rocking motion. In other words, oscillating member 74 pivots up on one end and then down on the other end. This type of oscillating motion happens several times a second. The user can also activate the motor(s) 60 to produce the linear motion while the oscillating motion occurs, so the invention can produce both stroking (linear) and oscillating (seesaw, rocking or pivots) motion at the same time through the coupler 65 that both motions can be translated to the pad or removable accessory 63 . The purpose for these types of motion so that the pad or removable accessory 63 would be able to contact spaces between the tiles (kitchen or bathroom) or lumbers (deck) removing the dirt between crevices.
[0028] The cleaning system has two main parts. The first is a transfer unit 52 . The transfer unit 52 is a caddy 50 for holding removable and replaceable pumps 54 and vacuum motors (not shown). The cartridge style pumps 54 come in different varieties, such as 1. water (cold, hot, mist, high and low pressure or steam), 2. chemicals (detergents, acids, caustics, sealants, finishes, stains, paints, herbicides and pesticides), 3. Air flow (suction, blowing, compressed, cold, or warm air). The caddy 50 can be made in many styles like portable, upright, canister, back pack, truck mounted or integrated for cars and homes. Each model will have the same interchangeable pump concept 54 .
[0029] The transfer unit 52 is made in this manner for a few of reasons: 1. Commercial customers can change the pumps 54 at the job site; 2. The transfer unit 52 can be upgraded or customized to suit individual customer needs; 3. It covers all the basic water or chemical needs for virtually any type of janitorial cleaning without changing the entire system; 4. There will be a great arsenal of products for upgrading.
[0030] In a way, the transfer unit 52 is designed like a personal computer. The pumps 54 and motors (not shown) can be considered “plug and play” devices. Just as you can change the floppy, CD, or DVD in a computer without changing the whole tower, you can change the pumps and motor just by plugging it in without replacing the whole transfer unit 52 .
[0031] Fluids and solids travel through the hoses 20 , 20 a , 24 to and from the transfer unit 52 . The hoses 20 , 20 a , 24 are flexible and resistant to chemicals and heat. A quick connect coupling with shut off valves will be on each end for fast connection and removal.
[0032] A multi-function operating switch 26 of the system is located on the handle 14 . The handle 14 has buttons and switches for controlling vacuuming actuations, chemical transfer and water transfer. The control handle is a tubular shaped device and can take other shapes as well. One end of the device receives power from the transfer unit 52 . The other end has a threaded coupling for connecting pressure cleaning wands, spay nozzles or the wand and head assembly. This feature allows the system to be used as a pressure washer, chemical sprayer, or cleaning machine.
[0033] The second main part of the system is the wand 12 and head assembly 16 . This part of the system is a powered cleaning tool used by the operator to clean various surfaces. It primarily uses a high speed linear actuations (thousands to tens of thousands strokes per minute at up to ½ inch strokes) to move cleaning pad in a back and forth motion that is parallel to the surface for scrubbing, sanding, and polishing dirty surfaces. The cleaning wand 12 also uses a secondary actuation motion. Electromagnets are mounted on the cleaning pad unit 34 causing the accessory 38 to pulsate perpendicular to a surface at speeds up to 40,000 strokes per minute. The agitation coupled with interchangeable cleaning pads of different textures and materials can clean virtually any indoor or outdoor surface around homes, buildings, and vehicles. Indoor cleaning wands 12 have water spray nozzles for rinsing debris. Cleaning head or removable accessory 38 sizes will range from toothbrush size to extra wide floor cleaning models.
[0034] Every home, building and vehicle has different types of surfaces inside and out. Flooring alone can be carpet, linoleum, tile, hardwood, granite, laminate, marble, brick, etc. Each surface requires a different cleaning pad material 38 for optimum cleaning capabilities. The cleaning pads or removable accessory 38 will be made to match each type of surface. Cleaning pads or removable accessory 38 will be hard, or soft bristles, sponge, microfibers, soft cloth, aggressive or fine sanding material, etc.
[0035] The fresh water and chemical storage containers (also removable) 18 , 18 a are located in transfer unit caddy 50 . The debris container has two chambers 18 , 18 a . Once section is for dry debris, and the other is for wet debris. The suction air flow can be redirected from one chamber to the other by simply moving a lever, allowing wet or dry debris fall into its proper chamber. An operator can switch from dry to wet vacuum mode without having to manually remove the dust filter.
[0036] The invention is set up where it can produce both a linear motion and oscillating motion. However, it is also designed to produce either a linear or oscillating motion if the user desires it for such purposes. Through the user interface, the user can activate the invention to produce one of these motions or both the linear and oscillating motion.
[0037] 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. | An indoor/outdoor cleaning system includes a portable pressurized housing for containing cleaning fluids (water, chemicals, and mixtures thereof). Multiple hoses connect the interior of the housing with a cleaning wand. The wand includes a handle, a hollow trunk portion and a cleaning head. The multiple hoses have outlets adjacent the cleaning head for feeding water, cleaning chemicals, or surface treating fluids thereto. The outlets open adjacent a cleaning pad, which pad, which pad is attached to the cleaning head via a mechanism that allows the pad to move either in a linear or sinusoidal (rocking) motion or the combination of both motions thereof. A variety of cleaning pad accessories (brush, sponge, sanding pad, buffing pad, etc.) can be optionally attached to the cleaning pad based on the type of surface to be cleaned or treated. A suction conduit, disposed in the cleaning head, functions to draw used fluids away from the surface for safe disposal thereof. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a divisional of U.S. patent application Ser. No. 12/233,751, filed on Sep. 19, 2008, which claims priority to U.S. Provisional Patent Application Ser. No. 60/975,193, filed Sep. 26, 2007; the disclosure of each of which is hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to deuterium-enriched pioglitazone, pharmaceutical compositions containing the same, and methods of using the same.
BACKGROUND OF THE INVENTION
[0003] Pioglitazone, shown below, is a well known thiazolidinedione.
[0000]
[0000] Since pioglitazone is a known and useful pharmaceutical, it is desirable to discover novel derivatives thereof. Pioglitazone is described in U.S. Pat. No. 4,687,777; the contents of which are incorporated herein by reference.
SUMMARY OF THE INVENTION
[0004] Accordingly, one object of the present invention is to provide deuterium-enriched pioglitazone or a pharmaceutically acceptable salt thereof.
[0005] It is another object of the present invention to provide pharmaceutical compositions comprising a pharmaceutically acceptable carrier and a therapeutically effective amount of at least one of the deuterium-enriched compounds of the present invention or a pharmaceutically acceptable salt thereof.
[0006] It is another object of the present invention to provide a method for treating a disease selected from diabetes mellitus type 2 and/or non-alcoholic steatohepatitis, comprising administering to a host in need of such treatment a therapeutically effective amount of at least one of the deuterium-enriched compounds of the present invention or a pharmaceutically acceptable salt thereof.
[0007] It is another object of the present invention to provide a novel deuterium-enriched pioglitazone or a pharmaceutically acceptable salt thereof for use in therapy.
[0008] It is another object of the present invention to provide the use of a novel deuterium-enriched pioglitazone or a pharmaceutically acceptable salt thereof for the manufacture of a medicament (e.g., for the treatment of diabetes mellitus type 2 and/or non-alcoholic steatohepatitis).
[0009] These and other objects, which will become apparent during the following detailed description, have been achieved by the inventor's discovery of the presently claimed deuterium-enriched pioglitazone.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0010] Deuterium (D or 2 H) is a stable, non-radioactive isotope of hydrogen and has an atomic weight of 2.0144. Hydrogen naturally occurs as a mixture of the isotopes 1 H (hydrogen or protium), D ( 2 H or deuterium), and T ( 3 H or tritium). The natural abundance of deuterium is 0.015%. One of ordinary skill in the art recognizes that in all chemical compounds with a H atom, the H atom actually represents a mixture of H and D, with about 0.015% being D. Thus, compounds with a level of deuterium that has been enriched to be greater than its natural abundance of 0.015%, should be considered unnatural and, as a result, novel over their non-enriched counterparts.
[0011] All percentages given for the amount of deuterium present are mole percentages.
[0012] It can be quite difficult in the laboratory to achieve 100% deuteration at any one site of a lab scale amount of compound (e.g., milligram or greater). When 100% deuteration is recited or a deuterium atom is specifically shown in a structure, it is assumed that a small percentage of hydrogen may still be present. Deuterium-enriched can be achieved by either exchanging protons with deuterium or by synthesizing the molecule with enriched starting materials.
[0013] The present invention provides deuterium-enriched pioglitazone or a pharmaceutically acceptable salt thereof. There are twenty hydrogen atoms in the pioglitazone portion of pioglitazone as show by variables R 1 -R 20 in formula I below.
[0000]
[0014] The hydrogens present on pioglitazone have different capacities for exchange with deuterium. Hydrogen atom R 1 is easily exchangeable under physiological conditions and, if replaced by a deuterium atom, it is expected that it will readily exchange for a proton after administration to a patient. Hydrogen atom R2 may be exchanged for a deuterium atom by the action of D 2 SO 4 /D 2 O or NaOD/D 2 O. The remaining hydrogen atoms are not easily exchangeable for deuterium atoms. However, deuterium atoms at the remaining positions may be incorporated by the use of deuterated starting materials or intermediates during the construction of pioglitazone.
[0015] The present invention is based on increasing the amount of deuterium present in pioglitazone above its natural abundance. This increasing is called enrichment or deuterium-enrichment. If not specifically noted, the percentage of enrichment refers to the percentage of deuterium present in the compound, mixture of compounds, or composition. Examples of the amount of enrichment include from about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 16, 21, 25, 29, 33, 37, 42, 46, 50, 54, 58, 63, 67, 71, 75, 79, 84, 88, 92, 96, to about 100 mol %. Since there are 20 hydrogens in pioglitazone, replacement of a single hydrogen atom with deuterium would result in a molecule with about 5% deuterium enrichment. In order to achieve enrichment less than about 5%, but above the natural abundance, only partial deuteration of one site is required. Thus, less than about 5% enrichment would still refer to deuterium-enriched pioglitazone.
[0016] With the natural abundance of deuterium being 0.015%, one would expect that for approximately every 6,667 molecules of pioglitazone (1/0.00015=6,667), there is one naturally occurring molecule with one deuterium present. Since pioglitazone has 20 positions, one would roughly expect that for approximately every 133,340 molecules of pioglitazone (20×6,667), all 20 different, naturally occurring, mono-deuterated pioglitazones would be present. This approximation is a rough estimate as it doesn't take into account the different exchange rates of the hydrogen atoms on pioglitazone. For naturally occurring molecules with more than one deuterium, the numbers become vastly larger. In view of this natural abundance, the present invention, in an embodiment, relates to an amount of an deuterium enriched compound, whereby the enrichment recited will be more than naturally occurring deuterated molecules.
[0017] In view of the natural abundance of deuterium-enriched pioglitazone, the present invention also relates to isolated or purified deuterium-enriched pioglitazone. The isolated or purified deuterium-enriched pioglitazone is a group of molecules whose deuterium levels are above the naturally occurring levels (e.g., 5%). The isolated or purified deuterium-enriched pioglitazone can be obtained by techniques known to those of skill in the art (e.g., see the syntheses described below).
[0018] The present invention also relates to compositions comprising deuterium-enriched pioglitazone. The compositions require the presence of deuterium-enriched pioglitazone which is greater than its natural abundance. For example, the compositions of the present invention can comprise (a) a μg of a deuterium-enriched pioglitazone; (b) a mg of a deuterium-enriched pioglitazone; and, (c) a gram of a deuterium-enriched pioglitazone.
[0019] In an embodiment, the present invention provides an amount of a novel deuterium-enriched pioglitazone.
[0020] Examples of amounts include, but are not limited to (a) at least 0.01, 0.02, 0.03, 0.04, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, to 1 mole, (b) at least 0.1 moles, and (c) at least 1 mole of the compound. The present amounts also cover lab-scale (e.g., gram scale), kilo-lab scale (e.g., kilogram scale), and industrial or commercial scale (e.g., multi-kilogram or above scale) quantities as these will be more useful in the actual manufacture of a pharmaceutical. Industrial/commercial scale refers to the amount of product that would be produced in a batch that was designed for clinical testing, formulation, sale/distribution to the public, etc.
[0021] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0022] wherein R 1 -R 20 are independently selected from H and D; and the abundance of deuterium in R 1 -R 20 is at least 5%. The abundance can also be (a) at least 10%, (b) at least 15%, (c) at least 20%, (d) at least 25%, (e) at least 30%, (f) at least 35%, (g) at least 40%, (h) at least 45%, (i) at least 50%, (j) at least 55%, (k) at least 60%, (l) at least 65%, (m) at least 70%, (n) at least 75%, (o) at least 80%, (p) at least 85%, (q) at least 90%, (r) at least 95%, and (s) 100%.
[0023] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 is at least 100%.
[0024] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 2 is at least 100%.
[0025] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 is at least 50%. The abundance can also be (a) 100%.
[0026] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 4 is at least 50%. The abundance can also be (a) 100%.
[0027] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 5 -R 8 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0028] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 9 -R 12 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (e) 100%.
[0029] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 13 -R 14 and R 20 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0030] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 15 -R 19 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0031] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0032] wherein R 1 -R 20 are independently selected from H and D; and the abundance of deuterium in R 1 -R 20 is at least 5%. The abundance can also be (a) at least 10%, (b) at least 15%, (c) at least 20%, (d) at least 25%, (e) at least 30%, (f) at least 35%, (g) at least 40%, (h) at least 45%, (i) at least 50%, (j) at least 55%, (k) at least 60%, (l) at least 65%, (m) at least 70%, (n) at least 75%, (o) at least 80%, (p) at least 85%, (q) at least 90%, (r) at least 95%, and (s) 100%.
[0033] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 is at least 100%.
[0034] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 2 is at least 100%.
[0035] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 is at least 50%. The abundance can also be (a) 100%.
[0036] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 4 is at least 50%. The abundance can also be (a) 100%.
[0037] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 5 -R 8 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0038] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 9 -R 12 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0039] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 13 -R 14 and R 20 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0040] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 15 -R 19 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0041] In another embodiment, the present invention provides novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0042] wherein R 1 -R 20 are independently selected from H and D; and the abundance of deuterium in R 1 -R 20 is at least 5%. The abundance can also be (a) at least 10%, (b) at least 15%, (c) at least 20%, (d) at least 25%, (e) at least 30%, (f) at least 35%, (g) at least 40%, (h) at least 45%, (i) at least 50%, (j) at least 55%, (k) at least 60%, (l) at least 65%, (m) at least 70%, (n) at least 75%, (o) at least 80%, (p) at least 85%, (q) at least 90%, (r) at least 95%, and (s) 100%.
[0043] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 is at least 100%.
[0044] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 2 is at least 100%.
[0045] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 2 is at least 50%. The abundance can also be (a) 100%.
[0046] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 3 -R 4 is at least 50%. The abundance can also be (a) 100%.
[0047] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R5-R 8 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0048] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 9 -R 12 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0049] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 13 -R 14 and R 20 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0050] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 15 -R 19 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0051] In another embodiment, the present invention provides novel pharmaceutical compositions, comprising: a pharmaceutically acceptable carrier and a therapeutically effective amount of a deuterium-enriched compound of the present invention.
[0052] In another embodiment, the present invention provides a novel method for treating a disease selected from diabetes mellitus type 2 and/or non-alcoholic steatohepatitis comprising: administering to a patient in need thereof a therapeutically effective amount of a deuterium-enriched compound of the present invention.
[0053] In another embodiment, the present invention provides an amount of a deuterium-enriched compound of the present invention as described above for use in therapy.
[0054] In another embodiment, the present invention provides the use of an amount of a deuterium-enriched compound of the present invention for the manufacture of a medicament (e.g., for the treatment of diabetes mellitus type 2 and/or non-alcoholic steatohepatitis).
[0055] The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. This invention encompasses all combinations of preferred aspects of the invention noted herein. It is understood that any and all embodiments of the present invention may be taken in conjunction with any other embodiment or embodiments to describe additional more preferred embodiments. It is also to be understood that each individual element of the preferred embodiments is intended to be taken individually as its own independent preferred embodiment. Furthermore, any clement of an embodiment is meant to be combined with any and all other elements from any embodiment to describe an additional embodiment.
Definitions
[0056] The examples provided in the definitions present in this application are non-inclusive unless otherwise stated. They include but are not limited to the recited examples.
[0057] The compounds of the present invention may have asymmetric centers. Compounds of the present invention containing an asymmetrically substituted atom may be isolated in optically active or racemic forms. It is well known in the art how to prepare optically active forms, such as by resolution of racemic forms or by synthesis from optically active starting materials. All processes used to prepare compounds of the present invention and intermediates made therein are considered to be part of the present invention. All tautomers of shown or described compounds are also considered to be part of the present invention.
[0058] “Host” preferably refers to a human. It also includes other mammals including the equine, porcine, bovine, feline, and canine families.
[0059] “Treating” or “treatment” covers the treatment of a disease-state in a mammal, and includes: (a) preventing the disease-state from occurring in a mammal, in particular, when such mammal is predisposed to the disease-state but has not yet been diagnosed as having it; (b) inhibiting the disease-state, e.g., arresting it development; and/or (c) relieving the disease-state, e.g., causing regression of the disease state until a desired endpoint is reached. Treating also includes the amelioration of a symptom of a disease (e.g., lessen the pain or discomfort), wherein such amelioration may or may not be directly affecting the disease (e.g., cause, transmission, expression, etc.).
[0060] “Therapeutically effective amount” includes an amount of a compound of the present invention that is effective when administered alone or in combination to treat the desired condition or disorder. “Therapeutically effective amount” includes an amount of the combination of compounds claimed that is effective to treat the desired condition or disorder. The combination of compounds is preferably a synergistic combination. Synergy, as described, for example, by Chou and Talalay, Adv. Enzyme Regul. 1984, 22:27-55, occurs when the effect of the compounds when administered in combination is greater than the additive effect of the compounds when administered alone as a single agent. In general, a synergistic effect is most clearly demonstrated at sub-optimal concentrations of the compounds. Synergy can be in terms of lower cytotoxicity, increased antiviral effect, or some other beneficial effect of the combination compared with the individual components.
[0061] “Pharmaceutically acceptable salts” refer to derivatives of the disclosed compounds wherein the parent compound is modified by making acid or base salts thereof. Examples of pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of the basic residues. The pharmaceutically acceptable salts include the conventional quaternary ammonium salts of the parent compound formed, for example, from non-toxic inorganic or organic acids. For example, such conventional non-toxic salts include, but are not limited to, those derived from inorganic and organic acids selected from 1,2-ethanedisulfonic, 2-acetoxybenzoic, 2-hydroxyethanesulfonic, acetic, ascorbic, benzenesulfonic, benzoic, bicarbonic, carbonic, citric, edetic, ethane disulfonic, ethane sulfonic, fumaric, glucoheptonic, gluconic, glutamic, glycolic, glycollyarsanilic, hexylresorcinic, hydrabamic, hydrobromic, hydrochloric, hydroiodide, hydroxymaleic, hydroxynaphthoic, isethionic, lactic, lactobionic, lauryl sulfonic, maleic, malic, mandelic, methanesulfonic, napsylic, nitric, oxalic, pamoic, pantothenic, phenylacetic, phosphoric, polygalacturonic, propionic, salicyclic, stearic, subacetic, succinic, sulfamic, sulfanilic, sulfuric, tannic, tartaric, and toluenesulfonic.
EXAMPLES
[0062] Table 1 provides compounds that are representative examples of the present invention. When one of R 1 -R 20 is present, it is selected from H or D.
[0000]
1
2
3
4
5
6
7
8
9
[0063] Table 2 provides compounds that are representative examples of the present invention. Where is shown, it represents naturally abundant hydrogen.
[0000]
10
11
12
13
14
15
16
17
18
[0064] Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise that as specifically described herein. | The present application describes deuterium-enriched pioglitazone, pharmaceutically acceptable salt forms thereof, and methods of treating using the same. | 2 |
This application claims the benefit of priority to Korean Patent Application No. 2003-100692 filed on Dec. 30, 2003, herein incorporated by reference.
BACKGROUND
1. Field
The present invention relates to a transflective type liquid crystal display device, and more particularly, to a transflective type liquid crystal display device and method for manufacturing the same, capable of optimizing optical efficiency.
2. Description of the Related Art
Generally, liquid crystal display (LCD) devices have advantages such as being lightweight, having a slim profile, and low power consumption, and are widely used for portable computers, office automation equipment, and audio/video apparatuses.
The LCD device includes two substrates and a liquid crystal layer interposed between the two substrates, and displaces liquid crystal molecules using an electric field generated upon application of a voltage. Hence, an image is displayed by manipulating the transmission of light through the liquid crystal.
Since the LCD device does not generate light by itself, it uses ambient light or a backlight assembly for generating light. Generally, the LCD device can be classified into two different categories: a transmission type LCD device or a reflection type LCD device.
FIG. 1 is a cross-sectional view schematically showing a structure of the transmission type LCD device according to the related art. In FIG. 1 , the transmission type LCD device includes: a first substrate 102 on which a thin film transistor (TFT) functioning as a switching element is formed on each of intersection points between a plurality of gate lines and data lines; a second substrate 101 which faces the first substrate 102 and on which a black matrix (BM) layer, a color filter layer, and a common electrode are formed; a liquid crystal layer 103 including liquid crystals interposed between the first and the second substrates 102 and 101 ; first and the second polarizing plates 105 and 104 arranged on an outer surface of each of the first and the second substrates 102 and 101 ; and a backlight assembly 106 disposed outside the first polarizing plate 105 .
An optical transmission axis of the first polarizing plate 105 has an angle of 90° to that of the second polarizing plate 104 . The backlight assembly 106 generates light and provides the light toward the first substrate 102 .
In the related art LCD device having the foregoing construction, when the TFTs are turned on by a scanning signal applied to the plurality of gate lines and a data voltage applied to the plurality of data lines, the data voltage is applied to pixel electrodes through the turned-on TFTs. At this time, a common voltage is supplied to the common electrode of the second substrate 101 . Accordingly, the liquid crystal molecules are controlled by the electric field generated between the pixel electrodes and the common electrode to transmit or block light provided from the backlight assembly 106 , so that a predetermined image is displayed.
However, in the transmission type LCD device of the related art, it is difficult to realize slimness and lightweight of the LCD device due to a large volume and a heavy weight of the backlight assembly 106 . Also, the power consumption of the backlight assembly 106 increases the overall power consumption of the device by a significant amount.
Therefore, research into reflection type LCD devices using ambient light instead of the backlight assembly 106 is actively performed. Such a reflection type LCD device is widely used as a portable display device such as an electronic organizer and a PDA (Personal Digital Assistant) thanks to low power consumption.
FIG. 2 is a cross-sectional view schematically showing a structure of the reflection type LCD device according to the related art. In FIG. 2 , the reflection type LCD device includes: a first substrate 202 on which a thin film transistor (TFT) functioning as a switching element is formed on each of crossing points between a plurality of gate lines and data lines; a second substrate 201 which faces the first substrate 202 and on which a black matrix (BM) layer, a color filter layer, and a common electrode are formed; a liquid crystal layer 203 including liquid crystals interposed between the first and the second substrates 202 and 201 ; a first and a second polarizing plates 205 and 204 arranged on an outer surface of each of the first and the second substrates 202 and 201 ; and a reflector 206 disposed outside the first polarizing plate 205 .
An optical transmission axis of the first polarizing plate 205 has an angle of 90° to that of the second polarizing plate 204 . The reflector 206 reflects light provided from the outside and provides the light toward the first substrate 202 .
In the LCD device having the foregoing construction, when a plurality of TFTs are turned on by a scanning signal applied to a plurality of gate lines and a data signal applied to a plurality of data lines, the data signal is applied to pixel electrodes through the turned-on TFTs. At this time, a common voltage is supplied to the common electrode of the second substrate 201 . Accordingly, the liquid crystals are controlled by the electric field generated between the pixel electrodes and the common electrode to transmit or block light provided and reflected from the outside, whereby a predetermined image is displayed.
However, in the related art reflection type LCD device, when ambient light does not have a sufficient intensity (for example, the surrounding environment is dim), the brightness level of the display image is lowered and displayed information is not readable, which is problematic.
To resolve the above problems, a transflective type LCD device, which combines the reflection type LCD device and the transmission type LCD device, has been suggested.
FIG. 3 is a cross-sectional view schematically showing a construction of the transflective type LCD device according to the related art. In FIG. 3 , the transflective type LCD device includes: a first substrate 330 on which a thin film transistor (TFT) functioning as a switching element is formed on each of crossing points between a plurality of gate lines and data lines; a second substrate 310 , which faces the first substrate 330 and on which a black matrix (BM) layer, a color filter layer, and a common electrode are formed; a liquid crystal layer 320 including liquid crystals interposed between the first and the second substrates 330 and 310 ; a first and a second polarizing plates 331 and 311 arranged on a lower surface of the first substrate 330 and an upper surface of the second substrates 310 , respectively; and a backlight assembly 340 disposed outside the first polarizing plate 331 .
An optical transmission axis of the first polarizing plate 331 has an angle of 90° to that of the second polarizing plate 311 .
On the first substrate 330 , a pixel electrode is connected to each TFT. On the pixel electrodes, a passivation layer 322 having a transmission hole 321 exposing a portion (transmission region) of each of the pixel electrodes and a reflector 323 are sequentially formed.
It is assumed that a region corresponding to the reflector 323 is a reflection region ‘r’ and a region corresponding to the portion of the pixel electrode, exposed by the transmission hole 321 , is a transmission region ‘t’. The reflection region ‘r’ is the region for reflecting light provided from ambient light in a reflection mode, and the transmission region ‘t’ is the region for transmitting light provided from the backlight assembly 340 in a transmission mode.
At this time, to reduce the difference in the distance that the light travels between the transmission region ‘t’ and the reflection region ‘r’, the cell gap d 1 of the transmission region ‘t’ is about twice that of the cell gap d 2 of the reflection region ‘r’.
Generally, a phase difference δ of a liquid crystal is obtained by the following formula:
δ=Δ n·d
where δ is the phase difference of a liquid crystal, Δn is the refractive index of a liquid crystal, and d is the cell gap.
Therefore, a difference in optical efficiency is generated between the reflection mode and the transmission mode. To reduce this difference in optical efficiency, the cell gap d 1 of the transmission region ‘t’ should be greater than the cell gap d 2 of the reflection region ‘r’ such that the phase difference value of the liquid crystal layer 320 is constant.
However, even though the difference in optical efficiency is reduced by making the cell gap d 1 of the transmission region t different from the cell gap d 2 of the reflection region r, it is difficult to optimize the transmission region and the reflection region. Therefore, it is difficult to obtain optimized optical efficiency. For example, in the transmission mode, not all of the light provided from the backlight assembly is transmitted through the transmission region, and some of the light impinges on the reflection region and is not transmitted, whereby optical loss occurs. Also, in the reflection mode, not all the ambient light is reflected by the reflector, and some of the ambient light impinges on the backlight assembly through the transmission region, whereby optical loss occurs.
SUMMARY
By way of introduction only, a transflective type LCD device of a first embodiment includes: a first substrate having a light guiding pattern containing a medium whose refractive index is different from a refractive index of the first substrate; a second substrate facing the first substrate; a liquid crystal layer disposed between the first and the second substrates; and a backlight assembly arranged on an outer surface of the first substrate.
A reflector may be formed on a pixel electrode formed on the first substrate such that a reflection region and a transmission region are provided. In this case, the reflector is formed in the reflection region and is not formed in the transmission region.
The reflection region may have a larger width than the transmission region. The light guiding pattern may be formed at the position that corresponds to the transmission region. Also, the refractive index of the light guiding pattern may be at least greater than that of the first substrate. The light guiding pattern may be tapered towards an inside thereof.
According to a second embodiment, a method for manufacturing a transflective type liquid crystal display includes: forming a predetermined pattern on a lower side of the substrate adjacent to a backlight assembly; and forming, in the pattern, a light guiding pattern made of medium whose refractive index is different from the refractive index of the substrate.
In another embodiment, the display device contains a light provider and a substrate having a periodic light guiding pattern formed therein. The light guiding pattern and substrate have different refractive indices that are different enough such that light from the light provider entering the light guiding pattern is directed by total internal reflection towards a front surface of the display device.
In another embodiment, the display device contains a light supplier, a reflector to reflect light from a light source external to the device towards the front surface, and means for redirecting light from the light supplier through total internal reflection towards the front surface.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
FIG. 1 is a cross-sectional view schematically showing a structure of a transmission type LCD device of the related art;
FIG. 2 is a cross-sectional view schematically showing a structure of a reflection type LCD device of the related art;
FIG. 3 is a cross-sectional view schematically showing a structure of a transflective type LCD device of the related art;
FIG. 4 is a cross-sectional view schematically showing a structure of a transflective type LCD device according to the first embodiment of the present invention;
FIG. 5 is a drawing showing a status in which light progresses by a light guiding pattern of the present invention in transmission mode;
FIGS. 6A , 6 B, 6 C and 6 D show the condition under which the total internal reflection occurs generally;
FIG. 7 is a drawing showing a total internal reflection path of light by a light guiding pattern of the present invention;
FIGS. 8A , 8 B and 8 C are sectional views illustrating a method for forming a light guiding pattern on a first substrate of a transflective type LCD device; and
FIG. 9 illustrates a light guiding pattern formed in a rectangular pattern.
DETAILED DESCRIPTION
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
FIG. 4 is a cross-sectional view schematically showing a structure of a transflective type LCD device according to a first embodiment of the present invention. In FIG. 4 , the transflective type LCD device includes: a first substrate 430 on which a thin film transistor (TFT) functioning as a switching element is formed on each of crossing points between a plurality of gate lines and data lines and a pixel electrode 437 is formed; a second substrate 410 facing the first substrate 430 and on which a black matrix (BM) layer, a color filter layer, and a common electrode are formed; a liquid crystal layer 420 including liquid crystals interposed between the first and the second substrates 430 and 410 ; first and second polarizing plates 431 and 411 arranged on a lower surface of the first substrate 430 and an upper surface of the second substrates 410 , respectively; and a backlight assembly 440 disposed on an outer surface of the first polarizing plate 431 .
An optical transmission axis of the first polarizing plate 431 has an angle of 90° to that of the second polarizing plate 411 .
The transflective type LCD device further includes a collimator 433 disposed between the first polarizing plate 431 and the backlight assembly 440 . The collimator 433 modulates an incident angle of light provided from the backlight assembly 440 such that parallel light is incident into the first substrate 430 .
Though not shown in FIG. 4 , each thin film transistor is connected to a gate line and a data line, and each pixel electrode is connected to the drain electrode of the TFT. Accordingly, the pixel region may include the TFT and the pixel electrode.
The pixel region can be divided into a reflection region ‘r’ and a transmission region ‘t’. Namely, a transmission hole 421 exposing a portion of the pixel electrode 437 , and a passivation layer 422 and a reflector 423 thereon are alternately arranged on the pixel electrode 437 . The region corresponding to the transmission hole 421 exposed by the pixel electrode 437 is the transmission region ‘t’ and the region corresponding to the reflector 423 is the reflection region ‘r’. The reflection region ‘r’ is the region that reflects light provided from ambient light in the reflection mode and the transmission region ‘t’ is the region that transmits light provided from the backlight assembly 440 in the transmission mode.
To reduce the difference between distances traveled by light through the transmission region t and the reflection region r, the cell gap d 1 of the transmission region t is about twice that of the cell gap d 2 of the reflection region r.
In the embodiment shown, the ratio of the width of the reflection region r to that of the transmission region t is 3:2. Namely, by making the width of the reflection region r greater than the width of the transmission region t, more ambient light can be reflected in the reflection mode, whereby the brightness can be increased. Therefore, optical loss is reduced and optical efficiency is improved, compared to the related art.
However, if the width of the reflection region r is greater than that of the transmission region, the width of the transmission region t is relatively small, so that the amount of light provided from the backlight assembly 440 through the transmission region t is reduced. The light guiding pattern 432 helps to mitigate this problem.
FIG. 5 shows how light is affected by the light guiding pattern in the transmission mode. As shown in FIG. 5 , in the transmission mode, light generated from the backlight assembly 440 is modulated into parallel light by the collimator 433 and provided to the first substrate 430 by way of the first polarizing plate 431 .
A light guiding pattern 432 capable of guiding light is formed on the first substrate 430 . The light guiding pattern 432 transmits incident light to be provided without any optical loss, to the transmission region t, through total internal reflection of the incident light. The light guiding pattern 432 is formed at the position that corresponds to the transmission region, which permits light that has traveled through using total internal reflection by the light guiding pattern 432 can be directly provided to the corresponding transmission region t.
Namely, light provided to the light guiding pattern 432 of the first substrate 430 is subject to total internal reflection inside the light guiding pattern 432 and is provided to the transmission region t. Therefore, since light generated from the backlight assembly 440 is provided to the transmission region t without any optical loss, the brightness is increased and the optical efficiency can be improved.
FIG. 6 is a schematic view showing a condition under which the total internal reflection occurs generally. As shown in FIG. 6A , the relation between light transmitted and provided to and from media having different refractive indexes n i and n t , is given by the following formula:
sin θ i =n t /n i sin θ t
Here, θ i represents an incident angle, θ t represents a transmission angle, n i represents a refractive index of a medium through which light is provided, and n t represents a refractive index of a medium to which light is transmitted.
As revealed by the above formula, if the refractive index n i of the medium through which light is provided is greater than the refractive index n t of the medium to which light is transmitted, the transmission angle θ t is greater than the incident angle θ i .
As shown in FIG. 6B , as the incident angle θ i increases the transmission angle θ t also increases. Accordingly, the transmitted light approaches the boundary between the two media and the amount of transmitted light is greater than in the amount of reflected light.
Eventually, as shown in FIG. 6C , when the transmission angle θ t becomes 90°, the incident light is neither transmitted nor reflected. The incident angle θ i when the transmission angle θ t becomes 90°, is called a critical angle θ c . As shown in FIG. 6D , light provided at an angle greater than the critical angle θ c is completely reflected by total internal reflection.
FIG. 7 is a drawing showing a total internal reflection path of light by the light guiding pattern. As shown in FIG. 7 , to meet the total internal reflection condition, n 1 is greater than n 2 (n 1 >n 2 ). Here, n 1 represents the refractive index of the light guiding pattern 432 and n 2 represents the refractive index of the first substrate 430 .
Also, the incident angle θ is greater than the critical angle (θ c =arcsin (n 2 /n 1 )). Therefore, light that satisfies the above two conditions is not transmitted but completely reflected by total internal reflection. Here, θ represents an incident angle of the light guiding pattern 432 and θ c represents the critical angle. At this time, it should be noted that the reflective angle equals the incident angle.
Therefore, the refractive index n 1 of the light guiding pattern 432 is at least greater than the refractive index n 2 of the first substrate 430 . Generally, since the refractive index n 2 of the first substrate 430 is about 1.5, the refractive index n 1 of the light guiding pattern 432 is at least greater than 1.5.
Also, to get the incident light to be provided in the direction of the first substrate 430 by total internal reflection, the light guiding pattern 432 is tapered from a lower part thereof to an upper part. By tapering the width of the upper part compared to that of the lower part, incident light is repeatedly reflected inside the light guiding pattern 432 by total internal reflection and provided to the first substrate 430 .
Therefore, the transflective type LCD device of the present invention can improve the optical efficiency through increase in optical transmittance by forming a light guiding pattern 432 for guiding light in the direction of the first substrate 430 and providing the light from the backlight assembly 440 completely to the transmission region t of the first substrate 430 without any optical loss.
Also, the transflective type LCD device having the foregoing construction improves reflection efficiency by making the reflection region r having a larger width than that of the transmission region t so that a greater amount of incident ambient light is reflected upon the reflection mode, and improves optical transmittance by forming the light guiding pattern 432 so that light provided from the backlight assembly 440 is completely guided to the transmission region t by total internal reflection. As described above, the transflective type LCD device of the present invention can maximize the optical efficiency in both the reflection mode and the transmission mode.
In the meantime, FIGS. 8A through 8C are drawings explaining a manufacturing process for forming the light guiding pattern on the first substrate of the transflective type LCD device.
As shown in FIG. 8A , a V-shaped pattern is formed on one side of the first substrate 430 by etching. For example, if the first substrate 430 is etched using photolithography, a positive or negative type photoresist is coated on the first substrate 430 so that a photoresist layer 435 is formed.
Subsequently, as shown in FIG. 8B , an exposure mask (not shown) is positioned above the photoresist layer 435 and a specific portion of the photoresist layer 435 is exposed to exposure light of a particular wavelength. Thereafter, the exposed photoresist layer 435 is developed so that a predetermined pattern is formed. Etching is then performed using the patterned photoresist layer 435 as a mask.
More specifically, etchant partially passes through the patterned photoresist layer 435 and reacts with the first substrate 430 . Subsequently, by removing the patterned photoresist layer 435 , a V-shaped pattern is formed on the first substrate 430 . The V-shaped pattern is tapered such that the surface of the pattern has a larger width than the end of the V-shaped pattern inside the first substrate 430 .
As shown in FIG. 8C , the light guiding pattern 432 made of a medium having the refractive index different from the first substrate 430 is formed on the V-shaped pattern. The light guiding pattern 432 has a refractive index greater than the refractive index of the first substrate 430 so that total internal reflection may occur.
Alternatively, as shown in FIG. 9 , the light guiding pattern 532 may be formed on a first substrate 530 in rectangular shape.
As is apparent from the foregoing, the optical transmittance is increased by forming a light guiding pattern on a first substrate so that light provided from a backlight assembly is guided in the transmission mode. Also, the optical reflectance is increased by increasing the width of the reflection region formed on the first substrate so that more ambient light is reflected in the reflection mode. Thus, the optical efficiency is increased by increasing the optical reflectance and transmittance in the transflective type LCD device having a reflection mode and a transmission mode.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. | A liquid crystal display device includes a first substrate, a second substrate facing the first substrate, a liquid crystal layer made of liquid crystals injected between the first and the second substrates, and a backlight assembly arranged on an outer surface of the first substrate. The first substrate has a light guiding pattern containing a periodic structure formed from a medium whose refractive index is different from the refractive index of the first substrate. The light guiding pattern is operative to internally reflect light from the backlight assembly to a transmission region. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a U.S. National Stage under 35 USC 371 filing of International Application Number PCT/US2010/01000, entitled Articulating Laryngoscope filed on Apr. 2, 2010, which is a Nonprovisional Application of U.S. Provisional Application Ser. No. 61/166,037, entitled “FLOWERING LARYNGOSCOPE” filed on Apr. 2, 2009, which are both incorporated herein by reference.
FIELD OF THE INVENTION
The present invention is related generally to the field of laryngoscopes.
BACKGROUND OF THE INVENTION
The purpose of the laryngoscope is to aid in intubation. During the intubation process, a laryngoscope is used to open the airways and provide enough light to enable the user to pass an endotracheal tube through the vocal cords, securing the airway so as to provide ventilation to the lungs.
Orotracheal intubation by direct laryngoscopy is the method of airway management in critically ill and injured patients, as well as patients undergoing all types of surgery in which general anesthesia is used. Intubation is performed by anesthesiologists, nurse anesthetists, emergency medicine and critical care physicians, dentists and maxillofacial surgeons, veterinarians, and in the out-of-hospital setting by paramedics. Orotracheal intubation is performed many thousands of times daily in the US, and millions of times daily worldwide in operating rooms, emergency departments, intensive care units, and every ambulance in the world.
SUMMARY OF THE INVENTION
According to the invention, there is provided an articulating laryngoscope, as defined in claims 1 - 37 .
For a better understanding of the present invention, together with other and further objects thereof, reference is made to the accompanying drawings and detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustratively shown and described in reference to the accompanying drawings, in which:
FIGS. 1 and 2 illustrate the side and front views, respectively, of one embodiment of articulating laryngoscope 1 of the present invention in the closed position;
FIGS. 3 and 4 illustrate the side and front views, respectively, of one embodiment of articulating laryngoscope 1 of the present invention in the deployed or open position;
FIG. 5A is a perspective view of another embodiment of the present invention illustrating extension of the finger members;
FIG. 5B is a perspective view of the embodiment of FIG. 5A illustrating relative angular positions of finger members in the extended (open) position;
FIG. 6 is a perspective view of the embodiment in FIG. 5A in the closed position;
FIG. 7 is a block diagram schematic illustrating exemplary elements of the present invention; and
FIGS. 8A-C are illustrations of a protective sleeve;
FIGS. 9A-C are illustrations of modular finger holder embodiments;
FIG. 10A-B are illustrations of the illumination system of one embodiment of the present invention;
FIG. 11 is an illustration of flexion and extension of a finger member; and
FIG. 12 is a front view of an individual finger member illustrating 360° rotational capability.
DETAILED DESCRIPTION OF THE INVENTION
As used herein in the specification and claims, including as used in the examples and unless otherwise expressly specified, all numbers may be read as if prefaced by the word “about”, even if the term does not expressly appear. Also, any numerical range recited herein is intended to include all sub-ranges subsumed therein.
Articulation is defined as a joint on a finger.
Actuation is defined as the movement at or about one or more joints.
Articulating laryngoscope 1 is designed to be equipped with many functional features including but not limited to, mechanical opening of air passage for ease of intubation, illumination of an air passage during intubation and for examination, delivery of gases and liquids, including medications; suction for removal of fluids including blood and mucus; cauterization to stop bleeding; removal of foreign objects and biopsy specimens; real-time video during intubation to guidance of articulating laryngoscope 1 ; and video recording and camera still images for evaluation and teaching; and surgical instruments including, but not limited to, scalpel, staple and suture.
FIGS. 1 and 2 illustrate the side and front views, respectively, of one embodiment of articulating laryngoscope 1 having six (6) fingers or projections or phalanges 2 (terms are interchangeable) arranged in a generally U or C shape configuration 11 in the closed position. The U or C shape configuration 11 provides vision for the user of the articulating laryngoscope 1 to observe the uvula, palatine tonsils, oropharynx, esophagus, larynx, and trachea as articulating laryngoscope 1 is guided into position. Therefore, open side 12 of U or C shape configuration 11 is defined as being facing up in an opposing direction relative to handle 13 . Handle 13 can contain PLC 22 , trigger or controller 14 , AC/DC (battery) power source 29 , and interfaces/ports/connections for suction source 27 , oxygen source 28 , and other fluid delivery input 35 (See FIG. 7 ). Handle 13 operably connects and communicates with fingers 2 at interface 36 by mechanical and electrical means known to one of skilled in the art
FIGS. 3 , 4 , 5 A, 5 B, and 11 illustrate the structure of articulating laryngoscope 1 that provide the function of member actuation to open air passageways. Fingers 2 have joints 3 that couple together a plurality of segments 5 such that at least segments 5 of fingers 2 can articulate, which means movement upward, downward, or in a circular or elliptical path along or about a central axis C. FIG. 5A illustrates segments 5 can have different lengths 6 , and thickness or diameters 7 . Each segment 5 can be tapered 8 with thickness or diameter decreasing as adjacent segments 5 are attached at joints 3 from proximal end 4 and distal end 9 . A plurality of segments 5 form member 19 . Joints 3 provide functionality for manipulation of members 19 in many directions when actuated by a trigger 14 or other control mechanism.
FIGS. 3 and 4 illustrate side and front views, respectively, of articulating laryngoscope 1 deployed or open position where members 19 extend or flex toward, for example, tissue to open an airway of the oropharynx. FIGS. 5A-B illustrate another actuation of fingers 2 in a “flowering” arrangement where all fingers 2 are extending outwardly away from each other for the maximum opening. Fingers 2 can be manipulated to bring finger ends 15 of members 19 in contact therewith to grab or pinch an object for extraction.
With regards to the actuation mechanism, FIG. 6 is an illustration of a closed laryngoscope with one or more channels that can contain embedded wires 21 for controlled finger actuation, fiber optics or light emitting diodes (LED) 22 for illumination or video, and tubes 23 for suction and fluid delivery, including oxygen and medication.
Now turning to FIGS. 1 and 7 , one embodiment of the actuation mechanism includes a handle 13 with an interface coupler 42 to operably connect handle 13 with fingers 2 . Fingers 2 will interlock with handle 13 in such a way as to make physical and electrical communication with AC/DC (battery) power source 28 and PLC 22 , both of which are contained in handle 13 , and the moveable components in fingers 2 . For instance, the actuation may be driven by manual operator energy, for example squeezing trigger 14 mechanical links to finger 2 resulting in the displacement of a physical conducting element such as a metal wire 21 . At the interlocking point 36 on handle 13 , wire 21 can be coupled to a flexible transducing element 40 in finger 2 or finger tip 15 .
In one embodiment of flexible transducing element 40 can be spring hinges 41 at joints 3 . Displacement of wire 21 in handle 13 will thus result in commensurate displacement of the flexible transducing element 40 in finger 2 , resulting in flexion and extension of finger 2 about a central axis C ( FIGS. 5B and 11 ). Each finger 2 has its own central axis C as illustrated in FIGS. 1 , 3 , 5 B, and 11 . Axis C can be linear or non-linear. Flexion is defined is an angular inward movement (interior surface side) φ 1 , φ 2 , φ 3 (where φ 3 =φ 2 −φ 1 ), etc. of each finger segment 5 from central axis C, about 0° up to about 180°, and any angle therebetween. Extension is defined as an angular outward movement (exterior surface side) θ 1 , θ 2 , θ 3 (where θ 3 =θ 2 −θ 1 ), etc. of each segment 5 from central axis C, about 0° up to about −180°, and any angle therebetween.
Turning now to FIG. 11 for a detailed discussion of actuation. The actuation of the individual fingers 2 can be controlled in such a way as to facilitate flexion (solid image of individual finger 2 ) and extension (dotted line image of individual finger 2 ) in two directions about a central axis C. Though the following disclosure illustrates bi-directional linear motion (up and down), it is within the contemplation of this invention that individual finger 2 can also rotate 360° about axis C ( FIG. 12 ). The path can be circular 52 or elliptical 53 as shown in FIG. 11 . This action may be accomplished by integrating two separate conducting element (such as a metal wire 21 ) into finger 2 and handle 13 , one which transduces input energy to force for actuation, and the other which places restrictions or enables actuation in one direction about the axis while creating the opposite condition for the opposite direction. For instance, activation of the directional limiter (not shown) may slide two subsurface metal restrictors (not shown) into place and out of place, respectively, on opposite sides of a joint 5 , facilitating movement toward the side without a restrictor plate, and inhibiting movement toward the side with a restrictor plate. Conduction of actuation energy will then result in movement in the former direction.
As discussed above, members 19 include an embedded actuation mechanism 20 . As shown in FIG. 6 , one embodiment of actuation mechanism 20 includes a pair of wires 21 extending from proximal end 4 to finger tip 15 at distal end 9 . Both wires 21 are connected to trigger 14 to pull one of the wires to control actuation of a particular member 19 . Another embodiment of actuation mechanism 20 can be gears (not shown) in to joints 3 linked by rotating rods connected to a motor in handle 13 . Yet another embodiment of actuation mechanism 20 can be motors at joints 3 responsive to an electronic stimulus or a signal. Trigger 14 can be connected to actuation mechanism mechanically or electrically, such as by a programmable logic controller (PLC) 22 or controller with logic to determine which wire of the pair of wires to pull to actuate a member 19 . One or more strain gauge 23 disposed along the length of members 19 can be used to regulate pressure of members 19 against tissue. The pressure can be monitored by the user on display 30 ( FIG. 7 ) for manual termination of the member actuation when a pressure limit is reached or the termination can be automated with an automatic shutoff when a pressure limit is reached.
One embodiment of the present invention can lock finger 2 positions by locking of the trigger at a set displacement. Alternatively, the source of actuation may be electrical energy derived from a DC (battery) power source 29 or AC common line power source, in which case interface coupler 42 at the interface 36 on handle 13 will bring physical contact between conductive electrical wiring (not shown) in the handle and the designated in finger 2 , continuing through each finger segment 5 to a successive series of motors, in series or in parallel within each finger 2 .
Now turning to FIGS. 10A-B illustrating one embodiment of the illumination function of the present invention. Joints 3 can include an opening 10 for light illumination when member 19 is flexed or extended or closed. FIG. 5A illustrates another embodiment for light illumination that includes finger material being made of translucent or clear substrate containing subsurface light sources 16 (fiber optics or LEDs) below the external surface 17 of the material to protect the light source 16 from contamination or prevent malfunctioning of joint 3 due to blockage caused by foreign objects. FIG. 10B illustrates illumination of the oropharynx to view the trachea and esophagus for intubation with the light illumination system of the present invention.
Joints 3 can also use opening 10 for suction or other fluid delivery when member 19 is flexed or extended ( FIG. 10A ) or closed. Openings 10 can be disposed along segments 5 in any location, such as midway between joints 3 . Finger 2 can include a fluid delivery outlet 25 at finger end 15 capable of delivering forced air or other medical gases (including oxygen), liquids and medicines ( FIG. 2 ) as well as suction. A balloon (not shown) can be fluidly connected to end 15 of finger 2 by fluid delivery line 25 for inflation to open up the passage way or to close off a passage way.
Now returning to FIG. 5A illustrate another embodiment of the present invention including webbing 33 between members 19 to function as a barrier to hold back tissues such as the tongue, fluids (such as blood, saliva, mucus), food particles, or other foreign objects that obscure the vision of the user and block the passageway. Webbing 33 can be disposed between one pair of member 19 (as shown in FIG. 5A ) or between all members 19 .
FIG. 7 illustrates exemplary functions and component connectivity of articulating laryngoscope 1 . PLC 22 can control illumination of lights on/off/brightness/direction adjustment; suction on/off/pressure; automatic member actuation shutdown when members 19 exceeds a range of motion limit or when a strain gauge 23 embedded in finger tip 15 exceeds pressure limit; optical focus and field of view; camera on/off/video/still images/run time shutoff/routing of optical signal to display 30 /lens directional adjustment; scalpel actuation measured by depth of cut into tissue and stroke length of cut; oxygen flow rate and mixture; suction flow rate; grasping control logic 32 that accounts for strain gauge 23 readings to adjust actuation of members 19 to assure grasping pressure is not beyond crush limits to avoid destruction or disintegration of object within the patient.
Other embodiments of articulating laryngoscope 1 can also include the following features:
A. grasping control 32 can include member 19 pinching function to stop, for example, bleeding;
B. member 19 can include an endotracheal tube mounted on it;
C. member 19 can include a cauterizer mounted on end 15 to stop bleeding;
D. member 19 can be constructed in multiple sizes for infants, toddlers, teenager, adults, and animals. Size can also be adapted for dental use, vaginal examinations and procedures, and other cavity examinations and procedures.
E. member 19 can include a biopsy needle 51 .
Fingers 2 can be a monolithic structure formed from a single injection mold. Finger base structure 18 can be rigid at proximal end 4 over segment length 6 , where there is no relative movement between members 19 . The remaining portion of members 19 can be independently operable and moveable relative to adjacent members 19 .
Another embodiment of fingers 2 can be a plurality of assembled components wherein a plurality of members 19 are mechanically connected at joints 3 by any conventional means such as ball and socket, hinges, or straps. Materials for fingers 2 and members 19 can include plastic, carbon fiber, polymers, any semi-rigid material, or combination thereof. Material can have antibiotic and healing properties. Members 19 are sufficiently malleable to be self contouring to tissue during actuation that will distribute the force or pressure substantially evenly to prevent point contact for a prolonged period to minimize tissue damage.
Materials for handle 13 can include stainless steel, aluminum, plastic, carbon fiber, rubber, polymers, any semi-rigid material, or combination thereof.
Now turning to FIGS. 8A-C , disposable sleeve 34 can be slipped over member 19 without webbing to function as a protective covering for reusable fingers 2 to either minimize or eliminate the need for sterilization. One embodiment of sleeve 43 can be used for a single member 19 ( FIG. 8B ). Another embodiment of sleeve 44 can be used for an entire finger 2 assembly ( FIG. 8C ) similar to a glove.
Another embodiment of the present invention is modular and includes separate, removable fingers 2 that can be selected for its function (such as suction, fluid delivery, light optics, camera lens, and scalpel) and fitted within a holder for a plurality of fingers 2 . Fingers 2 can be made of a low cost, sterile material for disposable purposes or the fingers can be made of materials designed for repeated use and sterilization between uses. Now turning to FIGS. 9A-C with illustrations of embodiments of the present invention with a finger base for modular configurations to hold individual members 2 . FIG. 9A illustrates one embodiment of block holder 45 made of malleable material (for example plastic) for individual finger 2 . Block holder 45 includes finger attachment devices 46 that can be a hole to receive individual member 2 therein, or a pin to receive individual member 2 thereon. Pin 46 can include a hole therethrough for suction or fluid delivery. Block 45 can directly connect with handle 13 . FIGS. 9B-C illustrate holder embodiments 47 , 49 being generally U or C shaped and made of malleable material (for example plastic) having hole 48 to receive individual member 2 therein. Holder 47 includes a block 50 that can used to secure holder 47 while inserting and removing individual fingers 2 . Individual fingers 2 inserted into holder 47 , 49 can directly connect to handle 13 .
While the disclosure has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the embodiments. Thus, it is intended that the present disclosure cover the modifications and variations of this disclosure provided they come within the scope of the appended claims and their equivalents. | Articulating laryngoscope to aid in the intubation of patients by providing illumination of the oral cavity and trachea during the process having, for example, ‘fingers’ with fiber optic lights at the ends and at joints of the fingers, fingers spread open or ‘flower’ when the device is deployed, gently retracting and compressing soft tissues in the oral cavity and providing medical professionals with much better illumination of the passageway they are addressing, constructed from a malleable material, including rubber, plastics/polymers, and carbon fiber, instead of hard metal. The fingers may have multiple light sources to ensure a flooding of the patient's oropharynx with light. Some versions might have fiber-optic cameras connected to one or more fingers for use in teaching and research, and one might have suction capability to facilitate removal of solids and fluids, one embodiment can have at least one finger with a scalpel at its distal end. | 0 |
FIELD OF THE INVENTION
[0001] The present invention generally relates to securing the stomach to the diaphragm to treat (or as integral part of treating . . . ), for example, hiatal hernias and gastroesophageal reflux disease. The present invention more particularly relates to fixing the stomach to the diaphragm transorally without the need for invasive surgical incisions.
BACKGROUND
[0002] A hiatal hernia is an anatomical abnormality in which part of the stomach protrudes through the diaphragm and up into the chest. Hiatal hernias are present in approximately 15% of the population and its occurrence increases with age. Recent studies estimate that it is present in 60-65% of those over 60 years of age.
[0003] Normally, the esophagus or food tube passes down through the chest, crosses the diaphragm, and enters the abdomen through a hole in the diaphragm called the esophageal hiatus. This “hole” is a muscular tube or channel of about two to three vertebrae in length. Just below the diaphragm, the esophagus joins the stomach at the gastroesophageal junction. In individuals with hiatal hernias, the opening of the esophageal hiatus (hiatal opening) is larger than normal, and a portion of the upper stomach slips up or passes (herniates) through the hiatus and into the chest. Although hiatal hernias are occasionally seen in infants where they probably have been present from birth, most hiatal hernias in adults are believed to have developed over many years.
[0004] It is thought that hiatal hernias develop as a part of permanent positive pressure in the abdomen and negative pressure in the chest with thousands of daily unsynchronized movements of the esophagus and diaphragm. Over time, the phrenoesophageal bundles or membrane elongate, allowing the gastroesophageal junction (GEJ) to slip into the chest. Widening is currently thought of as being the result of mechanical dilatation and recurrent inflammation in the herniated stomach (often referred to as the acid chamber) which leads to periesophagitis and retraction of the diaphragmatic muscle over time. As a result of the large opening, part of the stomach “slips” into the chest. Another potentially contributing factor is an abnormally loose attachment of the esophagus to the diaphragm which allows the esophagus and stomach to slip upwards.
[0005] Hiatal hernias are categorized as being either sliding or para-esophageal. Sliding hiatal hernias are those in which the junction of the esophagus and stomach, referred to as the gastro-esophageal junction, and part of the stomach protrude into the chest. The junction may reside permanently in the chest, but often it juts into the chest only during a swallow or if the patient is in a recumbent position. This occurs because with each swallow the muscle of the esophagus contracts causing the esophagus to shorten and to pull up the stomach through the widened diaphragm. When the swallow is finished, the esophagus relaxes and the herniated part of the stomach falls back into the abdomen. Para-esophageal hernias are hernias in which the gastro-esophageal junction stays where it belongs (attached at the level of the diaphragm), but part of the stomach passes or bulges into the chest beside the esophagus. The para-esophageal hernias themselves may remain in the chest at all times and are not affected by swallows.
[0006] A para-esophageal hiatal hernia that is large, particularly if it compresses the adjacent esophagus, may impede the passage of food into the stomach and cause food to stick in the esophagus after it is swallowed. Ulcers also may form in the herniated stomach due to the trauma caused by food that is stuck or acid from the stomach. Fortunately, large para-esophageal hernias are uncommon.
[0007] The vast majority of hiatal hernias are of the sliding type. The larger the hernia, the more likely it is to cause symptoms. When hiatal hernias produce symptoms, they may also be associated with gastro-esophageal reflux disease (GERD), to be described herein after, or its complications. GERD can occur because the formation of the hernia often interferes with the natural barrier which prevents acid from refluxing from the stomach into the esophagus. Patients with GERD are much more likely to have a hiatal hernia than individuals not afflicted by GERD. Thus, it is clear that hiatal hernias contribute to GERD.
[0008] Normally, there are several mechanisms to prevent acid from flowing backwards (refluxing) up into the esophagus. One mechanism involves a band of esophageal muscle where the esophagus joins the stomach called the lower esophageal sphincter that remains contracted most of the time to prevent acid from refluxing or regurgitating. The sphincter only relaxes when food is swallowed so that the food can pass from the esophagus and into the stomach. The area of the sphincter normally is attached firmly to the diaphragm in the hiatus through the phrenoesophageal membrane, and the muscle of the diaphragm, also called the crura of the diaphragm, wraps around the gastroesophageal junction and the sphincter, much like a scarf. The muscle that wraps around the diaphragm augments the pressure of the contracted sphincter and the gastroesophageal junction to further prevent reflux of acid.
[0009] Another mechanism that prevents reflux is the valve-like tissue at the junction of the esophagus and stomach just below the sphincter. The esophagus normally enters the stomach tangentially so that there is a sharp angle between the esophagus and stomach. The piece of tissue in this angle, composed of esophageal and stomach wall, forms a valve that can close off the opening to the esophagus at all times and even more, when pressure increases in the stomach, for example, during eating, when the stomach is filled. It can however open to allow gastric air or contents to pass into the esophagus in a healthy subject, e.g. during belching or vomiting.
[0010] When a hiatal hernia is present, two changes occur. First, the sphincter slides up into the chest while the diaphragm remains stationery. As a result, the pressure normally generated by the diaphragm overlying the sphincter and the pressure generated by the sphincter no longer overlap, and as a result, the total pressure at the gastro-esophageal junction decreases. Second, when the gastro-esophageal junction and stomach are pulled up into the chest with each swallow, the sharp angle where the esophagus joins the stomach becomes less sharp and the valve-like effect is lost. Both changes promote reflux of acid. With the diaphragm pinching the herniated stomach and the LES closing the esophagus, a “acid chamber” may result, leading to severe esophagitis with periesophagitis and potentially ulceration and bleeding. Due to the periesophagitis, the crura also retract, leading to a widening of the diaphragmatic opening over time and worsening of the hiatus hernia.
[0011] Hiatal hernias are diagnosed incidentally when an upper gastrointestinal x-ray or endoscopy is done during testing to determine the cause of upper gastrointestinal symptoms such as upper abdominal pain. On both the x-ray and endoscopy, the hiatal hernia appears as a separate “sac” lying between what is clearly the esophagus and what is clearly the stomach. This sac is delineated by the lower esophageal sphincter above and the diaphragm below.
[0012] Treatment of large para-esophageal hernias causing symptoms requires surgery. During surgery, the stomach is accessed invasively through incisions made in the abdomen or in the chest. The stomach is pulled down into the abdomen, the esophageal hiatus is made smaller, and the esophagus is attached to the diaphragm with sutures. Although the procedure restores the normal anatomy, it is invasive, requiring weeks or even months of recovery before all normal activity may be resumed.
[0013] As will be seen subsequently, the present invention provides an alternative procedure for treating hiatal hernias. Instead of being surgically invasive, the new procedure, according to the various embodiments described herein after, may be performed transorally without the need for invasive incisions. As a result, patients are able to recover much more quickly and return to normal activity within a few days.
[0014] Gastroesophageal reflux disease (GERD) is a chronic condition caused by the failure of the anti-reflux barrier located at the gastroesophageal junction to keep the contents of the stomach from splashing into the esophagus. The splashing is known as gastroesophageal reflux. The stomach acid is designed to digest meat and other foods, and will digest esophageal tissue when persistently splashed into the esophagus.
[0015] A principal reason for regurgitation associated with GERD is the mechanical failure of a deteriorated gastroesophageal valve to close and seal against high pressure in the stomach. Due to reasons including lifestyle, a Grade I normal gastroesophageal valve may deteriorate into a malfunctioning Grade III or absent valve Grade IV. With a deteriorated gastroesophageal valve, the stomach contents are more likely to be regurgitated into the esophagus, the mouth, and even the lungs. The regurgitation is referred to as “heartburn” because the most common symptom is a burning discomfort in the chest under the breastbone. Burning discomfort in the chest and regurgitation (burping up) of sour-tasting gastric juice into the mouth are classic symptoms of gastroesophageal reflux disease (GERD). When stomach acid is regurgitated into the esophagus, it is usually cleared quickly by esophageal contractions. Heartburn (backwashing of stomach acid and bile onto the esophagus) results when stomach acid is frequently regurgitated into the esophagus and the esophageal wall is inflamed.
[0016] Complications develop for some people who have GERD. Esophagitis (inflammation of the esophagus) with erosions and ulcerations (breaks in the lining of the esophagus) can occur from repeated and prolonged acid exposure. If these breaks are deep, bleeding or scarring of the esophagus with formation of a stricture (narrowing of the esophagus) can occur. If the esophagus narrows significantly, then food sticks in the esophagus and the symptom is known as dysphagia. GERD has been shown to be one of the most important risk factors for the development of esophageal adenocarcinoma. In a subset of people who have severe GERD, if acid exposure continues, the injured squamous lining is replaced by a precancerous lining (called Barrett's Esophagus) in which a cancerous esophageal adenocarcinoma can develop.
[0017] Other complications of GERD may not appear to be related to esophageal disease at all. Some people with GERD may develop recurrent pneumonia (lung infection), asthma (wheezing), or a chronic cough from acid backing up into the esophagus and all the way up through the upper esophageal sphincter into the lungs. In many instances, this occurs at night, while the person is in a supine position and sleeping. Occasionally, a person with severe GERD will be awakened from sleep with a choking sensation. Hoarseness can also occur due to acid reaching the vocal cords, causing a chronic inflammation or injury.
[0018] GERD never improves without intervention. Life style changes combined with both medical and surgical treatments exist for GERD. Medical therapies include antacids and proton pump inhibitors. However, the medical therapies only mask the reflux. Patients still get reflux and perhaps emphysema because of particles refluxed into the lungs. Barrett's esophagus results in about 10% of the GERD cases. The esophageal epithelium changes into tissue that tends to become cancerous from repeated acid washing despite the medication.
[0019] Several open laparotomy and laparoscopic surgical procedures are available for treating GERD. One surgical approach is the Nissen fundoplication. The Nissen approach typically involves a 360-degree wrap of the fundus around the gastroesophageal junction. The procedure has a high incidence of postoperative complications. The Nissen approach creates a 360-degree moveable valve without a fixed portion. Hence, Nissen does not restore the normal movable valve. The patient cannot burp because the fundus was used to make the repair, and may frequently experience dysphagia. Another surgical approach to treating GERD is the Belsey Mark IV (Belsey) fundoplication. The Belsey procedure involves creating a valve by suturing a portion of the stomach to an anterior surface of the esophagus. It reduces some of the postoperative complications encountered with the Nissen fundoplication, but still does not restore the normal movable valve. None of these procedures fully restores the normal anatomy or produces a normally functioning gastroesophageal junction. Another surgical approach is the Hill repair. In the Hill repair, the gastroesophageal junction is anchored to the posterior abdominal areas, and a 180-270 degree valve is created by a system of sutures. The Hill procedure restores the moveable portion of the valve, the cardiac notch and the Angle of His. However, all of these surgical procedures are very invasive, regardless of whether done as a laparoscopic or an open procedure.
[0020] New, less surgically invasive approaches to treating GERD involve transoral endoscopic procedures. One procedure contemplates a machine device with robotic arms that is inserted transorally into the stomach. While observing through an endoscope, an endoscopist guides the machine within the stomach to engage a portion of the fundus with a corkscrew-like device at the hinge point. The arm then pulls on the engaged portion to create a fold of tissue or radial plication at the gastroesophageal junction. The angle of His or the valve remain unaltered. Another arm of the machine pinches the excess tissue together and fastens the excess tissue with one pre-tied implant. This procedure does not restore normal anatomy. The fold created does not have anything in common with a valve. In fact, the direction of the radial fold prevents the fold or plication from acting as a flap of a valve.
[0021] Another transoral procedure contemplates making a fold of fundus tissue near the deteriorated gastroesophageal flap to recreate the lower esophageal sphincter (LES). The procedure requires placing multiple U-shaped tissue clips around the folded fundus to hold it in shape and in place.
[0022] This and the previously discussed procedure are both highly dependent on the skill, experience, aggressiveness, and courage of the endoscopist. In addition, these and other procedures may involve esophageal tissue in the repair. Esophageal tissue is fragile and weak, in part due to the fact, that the esophagus is not covered by serosa, a layer of very sturdy, yet very thin tissue, covering and stabilizing all intraabdominal organs, similar like a fascia covering and stabilizing muscle. Involvement of esophageal tissue in the repair of a gastroesophageal valve poses unnecessary risks to the patient, such as an increased risk of fistulas between the esophagus and the stomach.
[0023] A new and improved apparatus and method for restoration of a gastroesophageal flap valve is fully disclosed in U.S. Pat. No. 6,790,214, issued Sep. 14, 2004, is assigned to the assignee of this invention, and is incorporated herein by reference That apparatus and method provides a transoral endoscopic gastroesophageal flap valve restoration. A longitudinal member arranged for transoral placement into a stomach carries a tissue shaper that non-invasively grips and shapes stomach tissue. A tissue fixation device is then deployed to maintain the shaped stomach tissue in a shape approximating a gastroesophageal flap.
[0024] Since transoral GEFV restoration is a certain reality, it would be most desirable to be able to treat potentially related hiatal hernias in a similar manner to avoid invasive surgery altogether. The present invention addresses this and other issues.
SUMMARY
[0025] The invention provides a method comprising visualizing a wall of a patient's stomach adjacent the patient's diaphragm from within the patient's stomach, inserting a fastener deployment apparatus down the patient's esophagus and into the patient's stomach, and fastening the patient's stomach to the patient's diaphragm with the fastener deployment apparatus and from within the stomach. The fastening step may include fastening the patient's stomach to a crus of the patient's diaphragm, such as the right crus or to the muscular or tendenous portion of the diaphragm. The fastening step may in addition or alternatively include fastening the fundus of the patient's stomach to the patient's diaphragm.
[0026] The invention further provides an assembly comprising an elongated member including a proximal end and a distal end, and a fastener deployer carried at the distal end of the elongated member. The elongated member and fastener deployer are arranged to feed the fastener deployer down a throat and esophagus into a stomach. The fastener deployer is further arranged to fasten the stomach to an adjacent diaphragm. The assembly further comprises a visualization device that enables visualization of the stomach being fastened to the adjacent diaphragm.
[0027] The fastener deployer may be arranged to fasten the stomach to a crus of the diaphragm, such as the right crus. The fastener deployer may alternatively or additionally be arranged to fasten the fundus of the stomach to the diaphragm. The fastener deployer may comprise an elongated arm that positions the fastener deployer spaced away from the esophageal opening to the stomach and in contact with the fundus.
[0028] The visualization device may comprise an endoscope.
[0029] The elongated member may include a guide that guides the visualization device into the stomach.
[0030] The fastener deployer may include at least one fastener to be deployed. The fastener may comprise a first member, a second member, the first and second members having first and second ends, and a connecting member fixed to each of the first and second members intermediate the first and second ends and extending between the first and second members. The first and second members are separated by the connecting member. One of the first and second members has a through channel along the axis arranged to be slidingly received on a tissue piercing deployment wire.
[0031] The fastener may further comprise a slit extending between the first and second ends and communicating with the through channel.
[0032] The fastener deployer may further comprise a deployment wire arranged to be slidingly received by the through channel of the one of the first and second members, to pierce into the tissue to be fastened, and to guide the fastener into the tissue. The fastener deployer may further comprise a pusher that pushes the one of first and second members into the tissue while on the deployment wire and a guide tube extending over the deployment wire and the fastener that guides the deployment wire and fastener to the tissue. The fastener deployer may still further comprise an elongated arm that supports and positions the guide tube spaced away from the esophageal opening to the stomach and in proximity with fundus of the stomach.
[0033] The invention still further provides a method of treating a stomach disorder. The method comprises providing a transoral gastroesophageal valve restoration device, feeding the device down the esophagus into the stomach, forming a gastroesophageal valve with the device from within the stomach, fastening stomach tissue to maintain the gastroesophageal valve, and securing the stomach to the diaphragm from within the stomach.
[0034] The step of securing the stomach to the diaphragm may include fastening the stomach to a crus of the diaphragm, such as the right crus. The step of securing the stomach to the diaphragm may alternatively or additionally include fastening fundus of the stomach to the diaphragm.
[0035] The method may further comprise gripping the esophagus and displacing the esophagus until the stomach is completing within the diaphragm before securing the stomach to the diaphragm. The steps of gripping the esophagus and displacing the esophagus until the stomach is completing within the diaphragm may be performed before the step of forming a gastroesophageal valve with the device from within the stomach.
[0036] The invention still further provides a method of treating a hiatal hernia of a patient associated with the patient's esophagus, stomach, and diaphragm. The method comprises the steps of gripping the esophagus, displacing the esophagus towards the diaphragm until the stomach is completely positioned below the diaphragm, and securing the stomach to the diaphragm. The gripping, displacing, and securing steps are performed transorally.
[0037] The step of securing the stomach to the diaphragm may include fastening the stomach to the right crus of the diaphragm. The step of securing the stomach to the diaphragm may alternatively or additionally include fastening fundus of the stomach to the diaphragm.
[0038] The gripping step may include gripping sidewalls of the esophagus. The sidewalls of the stomach may be gripped with a vacuum.
[0039] The invention further provides a fastener deployment apparatus that deploys a fastener in body tissue. The apparatus comprises a window permitting visualization of internal body anatomy when placed in a body, a location marker viewable in the window, and a fastener deployer having a predetermined orientation relative to the location marker that ejects a fastener for deployment at a predetermined location relative to the location marker.
[0040] The invention further provides a method of treating a hiatal hernia and restoring a gastroesophageal valve of a patient. The method comprises the steps of gripping the esophagus, displacing the esophagus aborally to reduce the hiatal hernia, and manipulating tissue of the stomach while maintaining a grip on the esophagus to restore the gastroesophageal valve. The gripping, displacing, and manipulating steps are performed transorally.
[0041] The method may further comprise the step of securing the stomach to the diaphragm. The manipulating step may include forming a gastroesophageal valve flap and the method may further comprise deploying at lease one fastener through the gastroesophageal valve flap to maintain the valve and the reduced hiatal hernia.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may best be understood by making reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and wherein:
[0043] FIG. 1 is a front cross-sectional view of the esophageal-gastro-intestinal tract from a lower portion of the esophagus to the duodenum;
[0044] FIG. 2 is a partial perspective view with portions cut away of a stomach, esophagus, and diaphragm illustrating a hiatal hernia which may be treated according to an embodiment of the invention;
[0045] FIG. 3 is a side view of an apparatus for restoring a GEFV and securing the stomach to the diaphragm according to an embodiment of the invention;
[0046] FIG. 4 is a side view of the apparatus of FIG. 3 securing the stomach to the diaphragm according to an embodiment of the invention;
[0047] FIG. 5 is a perspective view, with portions cut away, of a device capable of securing the fundus of the stomach to the diaphragm according to another embodiment of the invention;
[0048] FIG. 6 is a simplified side view of an apparatus according to an embodiment of the invention being fed down an oral and esophageal passage of a patient;
[0049] FIG. 7 is a side view, partly in cross-section, of a device according to an embodiment of the invention after having been initially fed into a stomach to initiate a GERD treatment procedure according to an embodiment of the invention;
[0050] FIG. 8 is a view similar to FIG. 7 showing the device and stomach after the stomach has been inflated to a first pressure;
[0051] FIG. 9 is a view similar to FIG. 7 showing the device and stomach at a further stage of the procedure;
[0052] FIG. 10 is a view similar to FIG. 7 showing the device centered and gripping the esophagus;
[0053] FIG. 11 is a view similar to FIG. 7 showing the device initially gripping the stomach tissue after the stomach has been reinflated to a second, higher pressure;
[0054] FIG. 12 is a view similar to FIG. 7 showing the stomach partially deflated and gripped stomach tissue being pulled aborally towards the device;
[0055] FIG. 13 is a view similar to FIG. 7 showing the gripped stomach tissue being pulled to almost within the device;
[0056] FIG. 14 is a view similar to FIG. 7 showing the gripped stomach tissue within the device, being molded, and ready to receive a fastener;
[0057] FIG. 15 is a view similar to FIG. 7 showing the molded stomach tissue after receiving a fastener;
[0058] FIG. 16 is a perspective view illustrating a manner in which the devices of FIGS. 3 and 5 may deploy a fastener for securing the stomach to the diaphragm, for example; and
[0059] FIG. 17 is a perspective view showing a fastener fully deployed.
DETAILED DESCRIPTION
[0060] FIG. 1 is a front cross-sectional view of the esophageal-gastro-intestinal tract 40 from a lower portion of the esophagus 41 to the duodenum 42 . The stomach 43 is characterized by the greater curvature 44 on the anatomical left side and the lesser curvature 45 on the anatomical right side. The tissue of the outer surfaces of those curvatures is referred to in the art as serosa tissue. As will be seen subsequently, the nature of the serosa tissue is used to advantage for its ability to bond to like serosa tissue.
[0061] The fundus 46 of the greater curvature 44 forms the superior portion of the stomach 43 , and traps gas and air bubbles for burping. The esophageal tract 41 enters the stomach 43 at an esophageal orifice below the superior portion of the fundus 46 , forming a cardiac notch 47 and an acute angle with respect to the fundus 46 known as the Angle of His 57 . The lower esophageal sphincter (LES) 48 is a discriminating sphincter able to distinguish between burping gas, liquids, and solids, and works in conjunction with the fundus 46 to burp. The gastroesophageal flap valve (GEFV) 49 includes a moveable portion and an opposing more stationary portion.
[0062] The moveable portion of the GEFV 49 is an approximately 180 degree, semicircular, gastroesophageal flap 50 (alternatively referred to as a “normal moveable flap” or “moveable flap”) formed of tissue at the intersection between the esophagus 41 and the stomach 43 . The opposing more stationary portion of the GEFV 49 comprises a portion of the lesser curvature 45 of the stomach 43 adjacent to its junction with the esophagus 41 . The gastroesophageal flap 50 of the GEFV 49 principally comprises tissue adjacent to the fundus 46 portion of the stomach 43 . It is about 4 to 5 cm long ( 51 ) at it longest portion, and its length may taper at its anterior and posterior ends.
[0063] The gastroesophageal flap 50 is partially held against the lesser curvature 45 portion of the stomach 43 by the pressure differential between the stomach 43 and the thorax, and partially by the resiliency and the anatomical structure of the GEFV 49 , thus providing the valving function. The GEFV 49 is similar to a flutter valve, with the gastroesophageal flap 50 being flexible and closeable against the other more stationary side.
[0064] The esophageal tract is controlled by an upper esophageal sphincter (UES) in the neck near the mouth for swallowing, and by the LES 48 and the GEFV 49 at the stomach. The normal anti-reflux barrier is primarily formed by the LES 48 and the GEFV 49 acting in concert to allow food and liquid to enter the stomach, and to considerably resist reflux of stomach contents into the esophagus 41 past the gastroesophageal tissue junction 52 . Tissue aboral of the gastroesophageal tissue junction 52 is generally considered part of the stomach because the tissue protected from stomach acid by its own protective mechanisms. Tissue oral of the gastroesophageal junction 52 is generally considered part of the esophagus and it is not protected from injury by prolonged exposure to stomach acid. At the gastroesophageal junction 52 , the juncture of the stomach and esophageal tissues form a zigzag line, which is sometimes referred to as the “Z-line.” For the purposes of these specifications, including the claims, “stomach” means the tissue aboral of the gastroesophageal junction 52 .
[0065] FIG. 2 is a perspective view, with portions cut away, of stomach 43 , esophagus 41 , diaphragm 53 , and hiatal hernia 61 which may be treated according to an embodiment of the present invention. As previously mentioned, a principal reason for regurgitation associated with GERD is the mechanical failure of the deteriorated (or reflux appearance) gastroesophageal flap of the GEFV to close and seal against the higher pressure in the stomach. Due to reasons including lifestyle, a Grade I normal gastroesophageal flap of the GEFV may deteriorate into a Grade III deteriorated gastroesophageal flap. The anatomical results of the deterioration include moving a portion of the esophagus 41 that includes the gastroesophageal junction 52 and LES (not shown) toward the mouth through the hiatus 63 into the chest to create the hiatal hernia 61 . This greatly reshapes the anatomy aboral of the gastroesophageal junction 52 and forms a flattened fundus 46 .
[0066] Dr. Hill and colleagues developed a grading system to describe the appearance of the GEFV and the likelihood that a patient will experience chronic acid reflux. L. D. Hill, et al., The gastroesophageal flap valve: in vitro and in vivo observations , Gastrointestinal Endoscopy 1996:44:541-547. Under Dr. Hill's grading system, the normal movable flap 50 of the GEFV 49 illustrated in FIG. 1 is a Grade I flap valve that is the least likely to experience reflux. The deteriorated gastroesophageal flap 55 of the GEFV 49 illustrated in FIG. 2 is a Grade IV flap valve. The Grade IV flap valve is the most likely to experience reflux. Grades II and III reflect intermediate grades of deterioration and, as in the case of III, a high likelihood of experiencing reflux. With the deteriorated GEFV represented by deteriorated gastroesophageal flap 55 and the fundus 46 moved inferior, the stomach contents are presented a funnel-like opening directing the contents into the esophagus 41 and the greatest likelihood of experiencing reflux. Disclosed subsequently is a device, assembly, and method which may be employed to advantage according to an embodiment of the invention to treat the hiatal hernia 61 and restore the normal gastroesophageal flap valve anatomy.
[0067] Referring now to FIG. 3 , it shows a device 100 according to an embodiment of the present invention. The device 100 includes a longitudinal member 102 for transoral placement of the device 100 into the stomach. The device further includes a first member 104 , hereinafter referred to as the chassis, and a second member 106 , hereinafter referred to as the bail. The chassis 104 and bail are hingedly coupled at 107 . The chassis 104 and bail 106 form a tissue shaper which, as described subsequently in accordance with this embodiment of the present invention, shapes tissue of the stomach into the flap of a restored gastroesophageal flap valve. The chassis 104 and bail 106 are carried at the distal end of the longitudinal member 102 for placement in the stomach.
[0068] The device 100 has a longitudinal passage 101 to permit an endoscope 110 to be guided through the device and into the stomach. This permits the endoscope to service as a guide for guiding the device 100 through the patient's throat, down the esophagus, and into the stomach. It also permits the gastroesophageal flap valve restoration procedure to be viewed at each stage of the procedure.
[0069] As will be seen subsequently, to facilitate shaping of the stomach tissue, the stomach tissue is drawn in between the chassis 104 and the bail 106 . Further, to enable a flap of sufficient length to be formed to function as the flap of a gastroesophageal flap valve, the stomach tissue is pulled down so that the fold line is substantially juxtaposed to the opening of the esophagus into the stomach. Hence, as will be seen, the stomach is first gripped at a point out and away from the esophagus and the grip point is pulled to almost the hinged connection 107 of the chassis 104 and bail 106 . As described in copending application Ser. No. 11/001,666, filed Nov. 30, 2004, entitled FLEXIBLE TRANSORAL ENDOSCOPIC GASTROESOPHAGEAL FLAP VALVE RESTORATION DEVICE AND METHOD, which application is incorporated herein by reference, the device 100 is fed down the esophagus with the bail 106 substantially in line with the chassis 104 . To negotiate the bend of the throat, and as described in the aforementioned referenced application, the chassis 104 and bail 106 are rendered flexible. The chassis 104 is rendered flexible by the slots 108 and the bail 106 is rendered flexible by the hingedly coupled links 112 . Further details concerning the flexibility of the chassis 104 and the bail 106 may be found in the aforementioned referenced
[0070] As further shown in FIG. 3 , the device further includes a tissue gripper 114 . The gripper 114 , in this embodiment, comprises a helical coil 115 . The coil 115 is carried at the end of a cable 116 and may be attached to the end of the cable or be formed from the cable. In this embodiment, the helical coil 115 is attached to the cable 116 and is preceded by a guide 118 whose function will be described subsequently.
[0071] The helical coil 115 is shown in an approximate position to engage the stomach tissue out and away from the opening of the esophagus to the stomach. The helical coil 115 is guided into position by a guide structure 120 carried on the bail 106 . The guide structure 120 comprises a guide tube 122 . When the device 100 is first introduced down the esophagus into the stomach, the helical coil 115 is caused to reside well within the guide tube 122 to preclude the helical coil from accidentally or inadvertently snagging esophageal or stomach tissue.
[0072] The guide tube includes a longitudinal slit 126 having a circuitous configuration. The slit 126 permits the end of the cable to release or disassociate from the bail after the stomach tissue is gripped. The circuitous configuration of the slit 126 assures confinement of the cable 116 within the guide tube 122 until release of the cable is desired. The proximal end of the slit 126 has an enlarged portion or opening (not shown). This opening permits the cable and helical coil to reenter the lumen when the device 100 is readied for a repeated stomach tissue shaping procedure. To that end, the guide 118 has a conical surface that serves to guide the cable end back into the opening of the slit 126 .
[0073] With continued reference to FIG. 3 , the device 100 further comprises a fastener deployer 140 . The fastener deployer includes at least one fastener deployment guide 142 . The fastener deployment guide 142 takes the form of a guide lumen. Although only one guide lumen 142 is shown, it will be appreciated that the device 100 may include a plurality of such lumens without departing from the invention. The guide lumen terminates at a delivery point 144 where a fastener is driven from the device 100 and into, for example, the molded stomach tissue. The fastener deployer may also be used, according to an embodiment, to secure the stomach to the diaphragm.
[0074] The device 100 further includes a window 130 within the chassis 104 . The window is formed of a transparent or semi-transparent material. This permits gastroesophageal anatomy, and more importantly the gastroesophageal junction (Z-line) to be viewed with the endoscope 110 . The window includes a location marker 132 which has a know position relative to the fastener delivery point 144 . Hence, by aligning the marker with a known anatomical structure, the fastener will be delivered a known distance from or at a location having a predetermined relation to the marker. For example, by aligning the marker with the Z-line, it will be know that the fastener will be placed aboral of the Z-line and that serosa tissue will be fastened to serosa tissue. As previously mentioned, this has many attendant benefits.
[0075] It may also be mentioned at this point that the device 100 further includes an invaginator 145 including a plurality of orifices 146 . These orifices 146 , which alternatively may be employed on the longitudinal member 102 , are used to pull a vacuum to cause the device 100 to grip the inner wall surface of the esophagus. This will serve to stabilize the esophagus and maintain device positioning during the procedure. This vacuum gripping of the esophagus may also be used to particular advantage in the treatment of a hiatal hernia. Upon being thus gripped, the esophagus may be moved downwardly with the device toward the stomach to pull the stomach to within the diaphragm to eliminate the hiatal hernia.
[0076] Referring now to FIG. 4 , it shows the device 100 in position to secure the stomach 43 to the diaphragm 53 following a successful restoration of a GEFV flap and/or to treat a hiatal hernia. More particularly, the device 100 of FIG. 4 is shown positioned in the stomach 43 by the elongated member 102 . It is also rotated by about 180 degrees from its position shown in FIG. 3 to align the guide channel 142 with the lesser curve. This will enable the fastener deployer 140 to deploy at least one fastener 200 to secure the lesser curve 45 of the stomach 43 to the right crus 59 of the diaphragm 53 . The endoscope 110 is positioned in the stomach 43 and brought to a reflexed view as illustrated so that it may look back on the device 100 for visualization of the procedure.
[0077] The invaginator 145 has vacuum gripped the sidewalls of the esophagus. This permits the device to be used for displacing the esophagus aborally towards the stomach for reducing the hiatal hernia. Preferably the esophagus is displaced sufficiently so that the stomach is behind or within the diaphragm 53 . The esophagus is held in this position throughout the procedure.
[0078] Next, the fastener deployer deploys the at least one fastener 200 as illustrated. A deployment procedure for the application is described in greater detail herein after. The fastener is deployed to secure the lesser curve 45 of the stomach 43 to the right crus 59 of the diaphragm 53 . Of course, in an actual procedure, a plurality of spaced fasteners would be deployed.
[0079] Once the fasteners are deployed, the device 100 is removed from the stomach 43 . This may be accomplished by first aligning the bail 106 with the chassis 104 of the device 100 . The endoscope may be used as a guide to guide the device out of the stomach and through the esophagus, throat, and mouth.
[0080] With the stomach thus secured to the diaphragm, the original anatomy is restored to correct the hiatal hernia. As will be noticed, this has been accomplished, according to this embodiment completely transorally without the need for any invasive surgical procedures.
[0081] Referring now to FIG. 5 , it shows another device 300 according to an embodiment of the invention for securing the stomach 43 to the diaphragm 53 . Here, the fundus 46 of the stomach 43 is being secured to the diaphragm 53 .
[0082] The device 300 may be employed for the restoration of a GEFV 49 and/or to treat a hiatal hernia. The device 300 is carried at the distal end of an elongated member 302 for being transorally placed in the stomach 43 . It preferably includes an invaginator 345 of the type previously described for gripping the esophagus 41 and displacing it and the stomach aborally towards the diaphragm to reduce or eliminate the hiatal hernia. The invaginator may also be used to grip the esophagus during the restoration of the GEFV 49 after reduction of a hiatal hernia.
[0083] The device includes a support arm 312 that supports a fastener deployer 340 in close proximity to the fundus 46 of the stomach 43 . The fastener deployer includes a guide tube 342 supported by the arm 312 . The guide tube 342 guides the tissue piercing wire 364 and the fasteners 200 to the location where they are to be deployed. Again, a suitable deployment procedure and related deployment assembly are described herein after.
[0084] The device 300 further carries an endoscope 310 . Again, the endoscope is positioned to enable visualization of the procedure. It is guided by a guide channel 301 in the elongated member 302 .
[0085] The arm 312 is arranged for pivotal movement at 307 to enable proper positioning of the fastener deployer 340 . To that end, it may be noted that the arm reaches outwardly to displace the fastener deployer 340 and the fasteners 200 spaced away from the esophageal opening 39 to the stomach 43 .
[0086] Now that a device 100 according to an embodiment of the present invention and its use for treating a hiatal hernia has been described, a method of restoring the flap of a gastroesophageal flap valve according to this embodiment of the present invention will now also be described with reference to FIGS. 6-15 . The procedure for restoring the flap of a gastroesophageal flap valve begins with loading a fastener or a plurality of fasteners into the device 100 . As will be seen hereinafter, the fastener deployer includes a stylet which guides each fastener into the tissue to be fastened. The process of loading a fastener, according to this embodiment, includes snapping a fastener onto the stylet. A representative fastener and stylet will be described subsequently with respect to FIGS. 16 and 17 .
[0087] Next, the bail 106 is moved to be substantially in line with the chassis 104 . Next, the endoscope 110 is inserted into the device with an appropriate lubricant on the endoscope. Next, a bite block, of the type well known in the art, is inserted into the patient's mouth. A lubricant may be applied to the device and the device may now be inserted through the bite block in the subject's mouth. With the endoscope leading the device as illustrated in FIG. 6 , the endoscope and device combination are fed down the esophagus 141 into the stomach. Of course, when the endoscope 110 reaches its fully inserted position, the device 100 may be further advanced on the endoscope utilizing the endoscope as a guide to within the stomach of the patient.
[0088] As previously mentioned, the device 100 is able to clear the bend in the patient's throat by virtue of being flexible as previously described. With the endoscope serving as a guide tube, very little force should be needed to get the device around the neck into the pharynx and down into the esophagus.
[0089] FIG. 7 shows the device 100 upon reaching the interior of the stomach 43 . Here it may be seen that the bail 106 is substantially in line with the chassis 104 . The endoscope 110 remains within the device 100 . Also in FIG. 7 it may be noted that the stomach is deflated. This is the normal condition of the stomach when the stomach is empty.
[0090] Once the device is positioned in the stomach as shown in FIG. 7 , the stomach is inflated as shown in FIG. 8 by passing air through the endoscope into the stomach. The inflation of the stomach may be noted by the outward arcuate deflection of the stomach 43 . The stomach should be inflated to a first pressure just sufficient to open the stomach and provide good visibility of gastric folds on the interior wall 59 of the stomach. Visualization of such gastric folds permits discernment of a proper point to grip the stomach for forming the gastroesophageal flap valve flap in a manner to be described hereinafter. Once the stomach has been inflated to the first pressure, the device is placed in a desired position relative to the Z-line by placing the marker of the window 130 in a desired position relative to the Z-line 52 marking the transition from the esophagus 41 to the stomach 43 . In accordance with this embodiment, the marker 132 is aligned with the Z-line 52 . In order to visualize the marker and the Z-line, the endoscope 110 is pulled back into the device 100 and more particular adjacent the marker 132 to visualize when the marker is aligned with the Z-line 52 . With the marker 132 aligned with the Z-line 52 , the distance from the marker 132 to a proximal point of the elongated member 102 relative to a rather fixed anatomy site of the patient, such as an incisor may be measured. This measurement may be marked on the elongated member 102 and later utilized for positioning the marker 132 adjacent the Z-line 52 .
[0091] Referring now to FIG. 9 , with the stomach still inflated to the first pressure, the endoscope is positioned inside the device just past the hinged connection 107 of the bail 106 and chassis 104 . With the endoscope being located just past the hinged connection 107 , the bail is then actuated to an approximately one-half closed position as illustrated. As the bail moves, the bail should be watched to make sure that it moves towards the greater curve 56 so it can move freely in the open space of the gastric cavity. With the endoscope in the position as shown in FIG. 9 , the bail should be visible at all times.
[0092] Referring now to FIG. 10 , the endoscope 110 is advanced back into the stomach 43 and brought to a reflexed view as illustrated so that it may look back on the device 100 . With the operating end of the device in clear view, the device 100 is positioned in the center of the gastroesophageal flap valve to be formed where the posterior and anterior groove should be. This position is typically opposite the lesser curve 45 .
[0093] Next, the device positioning relative to the Z-line 52 is checked to make sure that the marker 132 is in its desired position relative to the Z-line 52 . In accordance with this embodiment, the marker 132 is placed adjacent or is aligned with the Z-line 52 .
[0094] With the device in the correct starting position as shown in FIG. 10 , a vacuum pump communicating with orifices 146 is energized to pull a vacuum through the orifices 146 . This causes the orifices to engage the wall of the esophagus 41 for gripping the esophagus. As previously mentioned, this invagination permits the esophagus to be pushed into the stomach by distal movement of the elongated member 102 to treat a hiatal hernia and to stabilize the position of the device within the stomach. The vacuum is continued to be pulled through the orifices 146 until the vacuum is above the 50 kps mark on the vacuum pump. The device is then pushed gently aborally to reposition the esophagus to correct a hiatal hernia. It may be noted that this maneuver can also be used to visually check the position of the faster delivery point 144 relative to the Z-line. During this maneuver, the esophagus may roll back on itself and expose the esophageal Mucosa and the Z-line adjacent to the fastener delivery ports.
[0095] Referring now to FIG. 11 , with the device locked in position by the vacuum orifices 146 , the area in which the helical coil is to be engaged may be identified. The gripping location may be largely determined by the size or length of the flap to be restored of the restored gastroesophageal flap valve. This of course may differ from one patient to another depending on the severity of the hiatal hernia and the degree of valve degradation. Once the gripping location is selected, the stomach 43 is inflated to a second and higher pressure. The inflation pressure of the stomach is increased to the second and higher pressure so that the Mucosa appears tight and the folds essentially flatten. With the correct gripping spot identified, the bail 106 is moved to position the tip of a helical coil 115 at the correct gripping spot. Next, the device 100 is gently pulled upwardly or orally until the bail contacts the tissue at the desired gripping spot. Next, the helix 115 is advanced by the pushing of the cable 116 until the helix pushes into the Mucosa. Next, the cable 116 is turned to likewise turn the helix 115 in a clockwise direction to screw the helix into the tissue. As the cable is turned, some wind-up may be filled in the helix drive cable.
[0096] With the helical coil 115 firmly seated in the tissue, the wind-up in the cable 116 is released. Referring now to FIG. 12 , with the retractor firmly seated in the tissue, the device 100 may be advanced slightly orally while at the same time the bail 116 may be opened slightly. This releases the cable 116 from the guide tube which has now been pulled back into the bail 106 . The cable 116 exits the guide tube 122 ( FIG. 3 ) by slipping through the circuitous slit 126 . This operation is more particularly described in the aforementioned U.S. patent application Ser. No. 11/061,318, filed Feb. 18, 2005, incorporated herein by reference. Also at this time, the correct positioning of the device relative to the Z-line may be verified.
[0097] With the bail 106 slightly opened and the helix 115 engaged with the tissue 43 , the interior of the stomach is now deflated through the endoscope 110 . The stomach should be deflated such that the tissue appears loose and collapsed with the Mucosa folds being prominent. However, enough room should be left to view the device.
[0098] Referring now to FIG. 13 , the gastric tissue is now gently pulled with the helix 115 and cable 116 towards the hinged connection 107 and the valve mold to be formed by the chassis 104 and closing bail 106 . Once the helix is fully retracted into the bail 116 , it is locked in place. The bail 106 may now be closed and the device and anatomy will appear as shown in FIG. 14 . Here it will be noted that the stomach tissue aboral of the Z-line 52 is confined between the bail 106 and chassis 104 to create a fold 150 . The fold is also adjacent the fastener delivery point 144 at the end of the fastener guide lumen. Since the fastener deployment point 144 is a known predetermined distance from the marker 132 of the window 130 , and since the marker 132 is aligned with the Z-line 52 , when a fastener is delivered from the fastener deployer of the device, the fastener will exit the fastener delivery point 144 at a point known to be aboral of the Z-line 52 . This assures that only serosa tissue is being adhered to serosa tissue in the fixation of the stomach tissue in creating the flap 150 . The flap 150 comprises layers 180 and 182 of stomach tissue.
[0099] With the tissue layers 180 and 182 now disposed within the mold of the chassis 104 and bail 106 , the bail 106 may now be locked with respect to the chassis 104 . It is now time to fasten the tissue layers 180 and 182 together by ejecting a fastener from the fastener deployer lumen 142 through the flap 150 from the fastener delivery point 144 . The fastener thus deployed will serve to maintain the restored GEFV and the reduced hiatal hernia.
[0100] Before a fastener is ejected from the fastener deployer lumen 142 , the stomach is once again inflated through the endoscope 110 . The stomach is inflated to a point where one has a good view of the tissue fold and bail 106 .
[0101] FIGS. 16 and 17 illustrate a manner in which the fasteners 200 may be deployed to fasten tissue layers 180 and 182 . The tissue layers 180 and 182 are meant to be merely representative of any tissue layers which may be fastened together, whether they be stomach tissue layers from forming a flap or stomach and diaphragm tissue layers fastened to secure the stomach to the diaphragm. The fastener 200 generally includes a first member 202 , a second member 204 , and a connecting member 206 . As may be noted in FIG. 15 , the first member 202 and second member 204 are substantially parallel to each other and substantially perpendicular to the connecting member 206 which connects the first member 202 to the second member 204 .
[0102] The first member 202 is generally cylindrical or can any shape. It has a channel 212 that extends therethrough. The though channel 112 is dimensioned to be slidingly received on a tissue piercing deployment wire 264 .
[0103] The first member 202 includes a pointed tip 224 . The tip 224 may be conical and more particularly takes the shape of a truncated cone. The tip can also be shaped to have a cutting edge in order to reduce tissue resistance.
[0104] The first member 202 also has a continuous lengthwise slit 225 . The slit 225 includes an optional slot 226 that communicates with the through channel 212 . The slot 226 has a transverse dimension for more readily enabling receipt of the tissue piercing deployment wire 264 during deployment of the fastener 200 . Also, because the fastener member 202 is formed of flexible material, the slit 225 may be made larger through separation to allow the deployment wire to be snapped into and released from the through channel 212 .
[0105] In addition to the fastener 200 and the deployment wire 264 , the assembly shown in FIGS. 16 and 17 further includes a pusher 266 and a guide tube 268 . The subassembly of the tissue piercing wire 264 , fastener 200 , and pusher 266 may be guided to its intended location relative to the tissue layers 180 and 182 by the guide tube 268 . The tissue piercing wire 264 , fastener 200 , and the pusher 266 are all initially within the guide tube 268 . The guide tube 268 is representative of the fastener deployment guide and to that end, includes the fastener deployment guide lumen 142 . The subassembly of the tissue piercing wire 264 , fastener 200 , and pusher 266 may be guided to its intended location relative to the tissue layers 180 and 182 by the guide lumen 142 .
[0106] As shown in FIGS. 16 and 17 , the tissue piercing wire 264 has a tip 270 helping it pierce the tissue layers 180 and 182 that will form the restored gastroesophageal flap valve flap 150 . The pusher 266 has pushed the first member 202 of the fastener 200 through the tissue layers 180 and 182 on the tissue piercing wire 264 . This may be accomplished by moving the wire 264 and the pusher 266 together.
[0107] As may be further noted in FIG. 16 , the first member 202 is clearing the wire 264 and tissue layer 182 . The tissue piercing wire 264 may now be retracted into the pusher 266 and the tissue piercing wire 264 and pusher 266 may be withdrawn.
[0108] FIG. 17 illustrates the fastener 200 in its fully deployed position. It will be noted that the fastener has returned to its original shape. The tissue layers 180 and 182 are fastened together between the first member 202 of the fastener 200 and the second member 204 of the fastener 200 . The connecting member 206 extends through the tissue layers 180 and 182 .
[0109] In accordance with a further method of utilizing the fastener deployment assembly of FIGS. 16 and 17 , the tissue piercing wire 264 may be first advanced through the tissue layers 180 and 182 by a full stroke and then locked. The tip 270 of the deployment wire 264 should extend through the bail 206 with minimal tenting of the tissue. Next, the pusher 266 is advanced. Visual confirmation that the first fastener member 202 is through the tissue is then made. In doing so, the very distal end of the pusher 266 may be visible when the first member 202 of the fastener 200 is fully deployed. Next, while holding the pusher 266 at the last noted position, the tissue piercing wire 264 is retracted. The first member 202 of the fastener 200 will fall to the side when the tissue piercing wire 264 reaches the pusher 266 . When the tissue piercing wire 264 reaches the pusher 266 and after the fastener 200 is deployed, the pusher 266 is pulled back with the tissue piercing wire. If additional fastener deployment guides are provided, the foregoing steps for deploying a fastener such as fastener 200 may be repeated.
[0110] With the fasteners successfully deployed, the vacuum pull through orifices 146 may now be turned off to release the device from the esophagus wall as illustrated in FIG. 15 . At this time, the bail 106 of the device 100 may be slightly opened and the helical coil 115 may be released from the stomach tissue. As may be seen in FIG. 15 , the procedure just described results in a flap 150 to be formed. At this time, an additional fastener or fasteners may be loaded onto the tissue piercing deployment wire 264 at the proximal end of the longitudinal member 102 .
[0111] To render the flap uniform about the opening of the orifice into the stomach, it is necessary at this time to rotate the device 102 and repeat the previously described procedure for forming a further flap portion. Before this is done, however, it is desirable to position the bail 106 to an almost closed position. Then, the device 100 is moved aborally further into the stomach until the tip end 107 of the bail 106 comes to rest on the tip 151 of the newly formed flap portion. This is the location where the helical coil 115 will next engage the stomach tissue for molding and fixating as previously described.
[0112] The foregoing is repeated until a complete valve flap is formed. When the appearance of the valve flap is satisfactory as viewed through the endoscope for visual confirmation, the helical coil 115 is reloaded back into its original position with the device 100 . The vacuum suction through orifices 146 is turned off to release the wall of the esophagus from the device. The bail 106 is then moved to a fully opened position as seen, for example, in FIG. 7 . The endoscope may now be retracted along with the stylet and pusher controls. With the retraction of the foregoing verified, the stomach may now be deflated and the device 100 may be removed from the stomach and esophagus. This then completes the GEFV restoration procedure according to this embodiment of the invention.
[0113] While particular embodiments of the present invention have been shown and described, modifications may be made, and it is thereto intended in the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention. | A patient's stomach may be secured to the patient's diaphragm. A method to accomplish this includes visualizing a wall of a patient's stomach adjacent the patient's diaphragm from within the patient's stomach, inserting a fastener deployment apparatus down the patient's esophagus and into the mammalian's stomach, and fastening the patient's stomach to the patient's diaphragm with the fastener deployment apparatus and from within the stomach. The procedure may be employed to advantage to treat a hiatal hernia, for example, either alone or in conjunction with the restoration of the patient's gastroesophageal flap valve. | 0 |
FIELD OF THE INVENTION
This invention relates to quinoline derivatives which have antiallergic effects in themselves and are useful as intermediates in the production of penicillin or cephalosporin derivatives.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide a quinoline derivative which has antiallergic effects in itself and is useful as an intermediate in the production of penicillin or cephalosporin derivatives.
According to the present invention, there is provided a quinoline derivative having the general formula ##STR2## where A represents a six-membered hydrocarbon ring; X represents an oxygen atom, an ═NOR 1 group in which R 1 is a hydrogen atom or a lower alkyl radical of from 1 to 5 carbon atoms, a hydroxyl group, or an --NHR 2 group in which R 2 is a hydrogen atom or an acyl group; and Y represents a hydrogen atom, a salt-forming radical, or an ester-forming radical.
DETAILED DESCRIPTION OF THE INVENTION
The quinoline derivatives within the scope of the present invention are novel compounds which have antiallergic effects in themselves and are useful as intermediates in the production of penicillin or cephalosporin derivatives. For example, as described in the Japanese Patent Application Nos. 24956/'78, now Japanese Patent Publication No. 119484/79, published Sept. 17, 1979 and 146055/'78 filed in the name of the Mitsui Toatsu Chemicals, Inc., a variety of penicillin derivatives can be synthesized by reacting a quinoline derivative of the present inventon having a reactive substituent on its carboxyl group with ampicillin. These penicillin derivatives have a wide antimicrobial spectrum and are useful in the treatment of infectious diseases owing to their powerful antibacterial activities against Gram-negative organisms, particularly those of the genus Pseudomonas. Specific examples of these penicillin derivatives include 6-[D-(-)-α-(4-hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxyamido)phenylacetamido]penicillanic acid, 6-[D-(-)-α-(4-hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxyamido)phenylacetamido]penicillanic acid, 6-[D-(-)-α-(5-ethoxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxyamido)phenylacetamido]penicillanic acid, 6-[D-(-)-α-(4,5-dihydroxy-5,6,7,8-tetrahydroquinoline-3-carboxyamido)phenylacetamido]penicillanic acid, 6-[D-(-)-α-(5-acetamido-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxyamido)phenylacetamido]penicillanic acid, and the like.
As has been described previously, the quinoline derivatives within the scope of the present invention have the general formula (1) given above. More specifically, the acyl group represented by R 2 is an R 1 CO-- group in which R 1 is a lower alkyl radical of from 1 to 5 carbon atoms. Specific examples of the salt-forming radical represented by Y include inorganic salt-forming radicals derived from sodium,, potassium, calcium, etc.; ammonium-forming radicals derived from ammonia, etc.; and organic salt-forming radicals derived from triethylamine, N-methylmorpholine, pyridine, etc. The ester-forming radical represented by Y can be any common radical that combines with the hydroxyl group to form an ester, and specific examples thereof include lower alkyl radicals of from 1 to 5 carbon atoms (which may have one or more halogen, amino, substituted amino, acyloxy, and other substituents) such as methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, etc.; aryl radicals (which may have one or more alkyl, halogen, nitro, amino, substituted amino, aminoalkyl, hydroxy, alkoxy, acyloxy, mercapto, alkylthio, trifluoromethyl, and other substituents) such as phenyl, etc.; aralkyl radicals (which may have one or more alkyl, halogen, nitro, amino, substituted amino, hydroxy, alkoxy, acyloxy, mercapto, alkylthio, trifluoromethyl, and other substituents) such as benzyl, p-methoxybenzyl, etc.; heterocyclic organic radicals such as succinimide, etc.; and the like.
Specific examples of the quinoline derivatives having the general formula (1) include 4-hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic acid, 4-hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxylic acid, 5-ethoxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid, 4,5-dihydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid, and 5-acetamido-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid; salts of the foregoing carboxylic acids; esters of the foregoing carboxylic acids; and the like.
The quinoline derivatives within the scope of the present invention can be prepared, for example, by the following procedures and by the procedures described in the examples which will be given later.
(1) 3-Amino-2-cyclohexenone is reacted with an ethoxymethylenemalonic acid diester to produce the corresponding N-(3-oxo-1-cyclohexen-1-yl)aminomethylenemalonic acid diester, which is then heated to subject it to ring cleavage and thereby obtain the corresponding 4-hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic acid ester.
(2) In the following procedures, the aforesaid 4-hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic acid ester is used as starting material.
(a) The starting material is hydrolyzed to produce 4-hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic acid.
(b) The starting material is reacted with hydroxylamine hydrochloride (NH 2 OH.HCl) to produce the corresponding 4-hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ester, which is then hydrolyzed to obtain 4-hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxylic acid.
(c) The aforesaid intermediate product, 4-hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ester, is reacted with an alkyl iodide (R 1 I) to produce the corresponding 5-alkyloxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ester, which is then hydrolyzed to obtain 5-alkyloxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid.
( 3) In the following procedures, the aforesaid 4-hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic acid ester is used as starting material.
(a) The starting material is reacted with zinc in acetic acid (Zn-AcOH) to produce the corresponding 5-amino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ester. This intermediate product is converted into the corresponding 5-acylamino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ester, which is then hydrolyzed to obtain 5-acylamino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid.
(b) The starting material is reacted with sodium boron hydride (NaBH 4 ) to produce the corresponding 4,5-dihydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ester, which is then hydrolyzed to obtain 4,5-dihydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid.
The preparation of the quinoline derivatives within the scope of the present invention is more fully illustrated by the following examples. However, these examples are only illustrative of the practice of the invention and should not be construed to limit the scope of the invention.
EXAMPLE 1
Synthesis of 4-Hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic Acid Ethyl Ester
(1) Synthesis of N-(3-Oxo-1-cyclohexen-1-yl)aminomethylenemalonic Acid Diethyl Ester
A mixture of 11.1 g of 3-amino-2-cyclohexenone, 24.2 g of ethoxymethylenemalonic acid diethyl ester, and 0.12 g of p-toluenesulfonic acid was heated on an oil bath at 120°-130° C. for 2 hours. Using column chromatography, the reaction product was purified to obtain a yield of 19.8 g of N-(3-oxo-1-cyclohexen-1-yl)aminomethylenemalonic acid diethyl ester in the form of a pale-yellow viscous oil. The n.m.r. spectrum (d 6 -DMSO, 60Mc, TMS) of this compound had signals at δ values of 1.24 (3H, t, J=7 Hz), 1.26 (3H, t, J=7 Hz), 1.7-2.75 (6H, m), 4.10 (2H, q, J=7 Hz), 4.18 (2H, q, J=7 Hz), 5.75 (H, s), 8.05 (1H, d, J=13.8 Hz), and 10.2 (1H, d, J=13.8 Hz).
(2) Synthesis of 4-Hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic Acid Ethyl Ester
Diphenyl ether (20 ml) was heated to 260° C. or above, and a solution of 6.87 g of N-(3-oxo-1-cyclohexen-1-yl)aminomethylenemalonic acid diethyl ester in 5 ml of diphenyl ether was added thereto drop by drop. The resulting reaction mixture was refluxed for 15 minutes. After being allowed to cool, the reaction mixture was poured into 300 ml of n-hexane. The precipitate so formed was separated by filtration and then purified to obtain a yield of 4.37 g of the desired compound in the form of a pale-yellow powder. This compound melted (and decomposed) at 221°-224° C. Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3340, 2960, 1740, 1690, 1635, 1605, 1560, 1510, 1285, 1170, 1150, 1090, 1035, 920 and 815 cm -1 , and its n.m.r. spectrum (d 6 -DMSO, 60Mc, TMS) had signals at δ values of 1.31 (3H, t, J=7 Hz), 1.9-3.1 (6H, m), 4.27 (2H, q, J=7 Hz), and 8.55 (1H, s).
EXAMPLE 2
Synthesis of 4-Hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic Acid
To 25 ml of water were added 4.0 g of 4-hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic acid ethyl ester and 2.9 g of sodium hydroxide. The resulting reaction mixture was stirred at 90°-95° C. for 2 hours. After being allowed to cool, the reaction mixture was adjusted to pH 2 with 6 N hydrochloric acid. The crystals so precipitated were separated by filtration, washed with water and ethyl alcohol, and then dried at 120° C. under reduced pressure for 4 hours to obtain a yield of 3.3 g of the desired compound. This compound melted (and decomposed) at 278°-279° C. Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3420, 1740, 1690, 1640, 1500, and 820 cm -1 .
EXAMPLE 3
Synthesis of 4-Hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid Ethyl Ester
To 80 ml of ethyl alcohol were added 2.35 g of 4-hydroxy-5-oxo-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ethyl ester and 0.69 g of hydroxylamine hydrochloride. The resulting reaction mixture was refluxed on an oil bath for 1 hour. After the ethyl alcohol was distilled off under reduced pressure, the residue was dissolved in dilute hydrochloric acid and the resulting solution was adjusted to pH 5.8 with 10% potassium carbonate. The crystals so precipitated were separated by filtration to obtain a yield of 1.8 g of the desired compound. This compound melted (and decomposed) at 245°-247° C. (uncorrected values). Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3240, 3060, 2960, 2920, 1720, 1650, 1550, and 1185 cm -1 , and its n.m.r. spectrum (CF 3 COOH, 60Mc, TMS) had signals at δ values of 1.50 (3H, t, J=7.5 Hz), 2.0-2.6 (2H, m), 3.0-3.5 (4H, m), 4.6 (2H, q, J=7.5 Hz), and 8.95 (1H, s).
EXAMPLE 4
Synthesis of 4-Hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid
Sodium hydroxide (1 g) was dissolved in 30 ml of water, and 1.5 g of the 4-hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ethyl ester obtained in Example 3 was added thereto. The resulting reaction mixture was stirred on an oil bath at 90° C. for 2 hours. After being cooled, the reaction mixture was adjusted to pH 2.2 with dilute hydrochloric acid. The crystals so precipitated were separated by filtration to obtain a yield of 1.2 g of the desired compound. This compound melted (and decomposed) at 285°-286° C. (uncorrected values). Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3440, 3180, 2880, 1650, 1520, 1400, 1230, 970, and 820 cm -1 .
EXAMPLE 5
Synthesis of 5-Ethoxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid Ethyl Ester
4-Hydroxy-5-hydroxyimino-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ethyl ester (3.75 g) was suspended in 100 ml of dimethylformamide and then dissolved therein by stirring the suspension on an oil bath at 95° C. Thereafter, 1.04 g of potassium carbonate and then 2.32 g of ethyl iodide were added thereto. The resulting reaction mixture was stirred for 4 hours. After the dimethylformamide was distilled off under reduced pressure, water and ethyl acetate were added to the residue. The organic layer was separated and then stripped of solvent to obtain a yield of 3.0 g of the desired compound. This compound melted at 89°-91° C. (uncorrected values). Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3440, 3000, 2960, 1740, 1640, 1465, 1220, 1190, 1110, 1060, and 990 cm -1 , and its n.m.r. spectrum (CDCl 3 , 60Mc, TMS) had signals at δ values of 1.38 (3H, t, J=6.75 Hz), 1.42 (3H, t, J=7.5 HZ), 1.7-2.2 (2H, m), 2.7-3.15 (4H , m), 4.25 (2H, q. J=6.75 Hz), 4.40 (2H, q, J=7.5 Hz), and 8.77 (1H, s).
EXAMPLE 6
Synthesis of 5-Ethoxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid
5-Ethoxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ethyl ester (2.0 g) was dissolved in a mixture of 20 ml of 1 N sodium hydroxide and 10 ml of ethyl alcohol. The resulting reaction mixture was stirred at 90° C. for 2 hours. Under cooling with ice, the reaction mixture was adjusted to pH 4 with dilute hydrochloric acid. The crystals so precipitated were separated by filtration to obtain a yield of 0.95 g of the desired compound. This compound melted (and decomposed) at 225°-228° C. (uncorrected values). Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3440, 2910, 1690, 1640, 1400, 1060, and 825 cm -1 , and its n.m.r. spectrum (CF 3 COOH, 60MC, TMS) had signals at δ values of 1.57 (3H, t, J=7.5 Hz), 2.0-2.6 (2H, m), 3.0-3.5 (4H, m), 4.59 (2H, q, J=7.5 Hz), and 8.94 (1H, s).
EXAMPLE 7
Synthesis of 4,5-Dihydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid Ethyl Ester
4-Hydroxy-5,6,7,8-tetrahydro-5-oxo-3-quinolinecarboxylic acid ethyl ester (11.5 g) was suspended in 600 ml of methyl alcohol, and 1.1 g of sodium boron hydride (NaBH 4 ) was added to the suspension with its internal temperature kept at 20°-25° C. After completion of the reaction, the methyl alcohol was distilled off under reduced pressure and 200 ml of water was added to the residue. The resulting solution was adjusted to pH 2.4 with dilute hydrochloric acid and stirred for 30 minutes. Then, under cooling, the solution was adjusted to pH 6.5 with dilute aqueous sodium hydroxide and stirred for 30 minutes. The precipitate so formed was separated by filtration to obtain a yield of 10.4 g of the desired compound. This compound melted at 182°-183° C. (uncorrected values). Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3440, 3160, 2960, 1730, 1655, 1540, 1305, and 1190 cm -1 , and its n.m.r. spectrum (CF 3 COOH, 60Mc, TMS) had signals at δ values of 1.52 (3H, t, J=6.8 Hz), 1.9-2.4 (4H, m), 2.9-3.3 (2H, m), 4.64 (2H, q, J=6.8 Hz), 5.48 (1H, bs), and 8.95 (1H, d, J=6.0 Hz).
EXAMPLE 8
Synthesis of 4,5-Dihydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid
4,5-Dihydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ethyl ester (4.7 g) was dissolved in 40 ml of 1 N sodium hydroxide. The resulting solution was stirred on an oil bath at 50° C. for 3 hours and then allowed to stand at room temperature overnight. After the small amount of insoluble matter was removed, the solution was adjusted to pH 2.4 with dilute hydrochloric acid. The precipitate so formed was separated by filtration to obtain a yield of 3.8 g of the desired compound. Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3400, 3060, 2960, 1700, 1650, 1530, and 1510 cm -1 , and its n.m.r. spectrum (CF 3 COOH, 60Mc, TMS) had signals at δ values of 1.8-2.6 (4H, m), 2.9-3.5 (2H, m), 5.55 (1H, bs), and 8.9-9.2 (1H, m).
EXAMPLE 9
Synthesis of 5-Amino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid Ethyl Ester
4-Hydroxy-5,6,7,8-tetrahydro-5-hydroxyimino-3-quinolinecarboxylic acid ethyl ester (2.5 g) was suspended in 90 ml of acetic acid, and 2.6 g of zinc dust was added to the suspension with its internal temperature kept at 60° C. The resulting reaction mixture was stirred for 5 hours. After the reaction mixture was filtered to remove the insoluble matter, the filtrate was concentrated to obtain the desired compound as a crude product. This crude product was used in the succeeding Example 10 without further purification.
EXAMPLE 10
Synthesis of 5-Acetamido-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid Ethyl Ester
The crude product obtained in Example 9 was dissolved in 150 ml of chloroform, and 7.5 g of acetic anhydride was added thereto. The resulting reaction mixture was allowed to stand overnight. The precipitate so formed was separated by filtration to obtain a yield of 1.1 g of the desired compound. Its n.m.r. spectrum (CF 3 COOH, 60Mc, TMS) had signals at δ values of 1.50 (3H, t, J=6.8 Hz), 1.8-2.6 (4H, m), 2.40 (3H, s), 2.9-3.4 (2H, m), 4.65 (2H, d, J=6.8 Hz), 5.65 (1H, d, J=8.3 Hz), 8.40 (1H, d, J=8.3 Hz), and 8.85-9.15 (1H, m).
EXAMPLE 11
Synthesis of 5-Acetamido-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid
5-Acetamido-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ethyl ester (0.8 g) was suspended in 20 ml of 1 N sodium hydroxide. The resulting reaction mixture was heated on an oil bath at 110° C. for 2 hours. After being cooled, the reaction mixture was filtered to remove the insoluble matter, and the filtrate was adjusted to pH 2.5 with dilute hydrochloric acid. The precipitate so formed was separated by filtration to obtain a yield of 0.4 g of the desired compound. This compound melted (and decomposed) at 285°-287° C. (uncorrected values). Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3420, 3340, 3260, 3080, 2940, 1710, 1650, 1635, 1290, and 810 cm -1 . and its n.m.r. spectrum (CF 3 COOH, 60Mc, TMS) had signals at δ values of 1.8-2.6 (4H, m), 2.43 (3H, s), 2.9-3.5 (2H, m), 5.72 (1H, d, J=8.3 Hz), 8.47 (1H, d, J=8.3 Hz), and 9.0-9.3 (1H, m). | Disclosed is a quinoline derivative having the general formula ##STR1## where A represents a six-membered hydrocarbon ring; X represents an oxygen atom, an ═NOR 1 group in which R 1 is a hydrogen atom or a lower alkyl radical of from 1 to 5 carbon atoms, a hydroxyl group, or an --NHR 2 group in which R 2 is a hydrogen atom or an acyl group; and Y represents a hydrogen atom, a salt-forming radical, or an ester-forming radical. This quinoline derivative is a novel compound which has antiallergic effects in itself and is useful as an intermediate in the production of penicillin or cephalosporin derivatives. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 09/876,762, filed on Jun. 7, 2001 now U.S. Pat. No. 7,249,095, entitled A SYSTEM AND METHOD FOR EXECUTING DEPOSIT TRANSACTIONS OVER THE INTERNET, which is based on U.S. Provisional Patent Application No. 60/209,937, filed on Jun. 7, 2000, entitled INTERNET TRADING SYSTEM FOR DEPOSITS. The contents of these applications are herein incorporated by reference.
FIELD OF THE INVENTION
The present invention generally relates to systems and methods for executing banking transactions, and more particularly to systems and methods for executing deposit trades over the Internet.
BACKGROUND OF THE INVENTION
One of the services historically offered by financial institutions, such as banks, are treasury services. One purpose of the treasury services performed by banks is to aid its customers, typically corporations, in the management of the corporation's cash flows. One treasury service offered by banks is the taking of deposits. Deposits are a term used to describe the taking of currencies from customers for an indefinite period of time (e.g., call deposits) or for a fixed time period, typically from overnight up to one year. For example, if the corporation has closed on the sale of some assets (e.g., a parcel of real property) and the corporation has not yet allocated the proceeds from the sale, the corporation has a need to do something with the proceeds until it has decided on the final use of the proceeds. Typically, the corporation will execute a deposit of the proceeds with the bank for that period of time.
A deposit has several attributes including the currency, the term and the interest rate. The first attribute is the currency of the deposit. In the global economy of today, a bank can be expected to receive and maintain deposits in several different currencies. Currencies are currently divided into major currencies and minor currencies. Some examples of major currencies are United States Dollars (USD) and the Euro (EUR). Minor currencies include Canadian Dollars (CAD) and Hong Kong Dollars (HKD). The term, also known as the tenor, of the deposit typically ranges from an overnight deposit to a deposit for a period of a few days, weeks, months or years. The interest rate paid on the deposit is primarily a function of the market at the time the deposit is made and varies depending on the term of the deposit as well the amount and currency of the deposit.
In the traditional method of taking deposits, the customer telephones a member of the trading desk at the bank. The trader takes the details of the deposit (amount, currency, tenor) and determines the rate at which the bank will take the deposit. The trader then gives the customer a quote (makes a bid) that the customer then either accepts or declines. If the customer accepts the bid, the trader inputs the details into a trading system that generates a deal ticket representative of the terms and conditions of the transaction between the bank and the customer. A paper confirmation is then forwarded to the customer for confirmation of the deal with respect to the deposit. Typically, the paper confirmation is forwarded to the customer by mail, facsimile or by other manual means. The customer executes the confirmation and forwards the executed confirmation back to the bank. The paper confirmation acts as documentation of the contract between the bank and the customer regarding the deposit.
One significant drawback with the prior art method of deposit taking is that the customer is provided with little information regarding the variety of options available with respect to the attributes of the deposit. As described above, the customer describes the nature of the deposit to the trader over the telephone and the trader replies with a quote with respect to the described deposit. The customer is typically not given any further information with respect to alternatives with respect to the deposit, such as different currencies or different tenors.
A drawback to banks operating according to the traditional deposit taking method is that it requires a large number of personnel in the functions of traders, salespeople and support staff. A large number of traders and salespeople must always be on call in order to provide quotes over the telephone and to book deals with respect to deposits. The manual process of generating and obtaining executed confirmations with respect to deposits requires extensive procedures and the personnel to execute those procedures. If the personnel fail to properly execute those procedures, particular deals may be inaccurately executed and/or documented (requiring investigation of the deal), and more significantly, customers that are dissatisfied with the customer service of the bank may take their business elsewhere.
Another significant limitation with the current system and method for taking deposits is the manual confirmation process. As just described, the process of generating and forwarding the confirmation to the customer, as well as receiving the executed confirmation from the customer is manually intensive and can be error prone. Furthermore, it takes time for the bank to generate and forward the confirmation to the customer. Errors may be not be resolved for some length of time during which interest rates may have changed with a resulting adverse economic impact to either the bank or the customer.
SUMMARY OF THE INVENTION
In light of the above problems associated with the traditional system and method for taking deposits, the present invention provides an automated way in which information regarding deposit options is presented to the customer, the way in which the deals regarding deposits are formed and the manner in which the deals are executed and confirmed.
In a preferred embodiment, the system is operated by a financial institution such as a bank for the benefit of its customers. The system is embodied as a web site and the bank customers securely access the system through the Internet. The main screen of the online trading system displays to the customers the bank's current rates for a plurality of currencies and a plurality of time periods. The time periods for the deposits range from overnight to several months or even a year. In a preferred embodiment, this information is presented to the customer in the form of a rate chart in a window on the user's workstation. Once the customer has found a time period/rate/currency that is acceptable, the customer selects the desired rate on the customer interface. The response of the system to this selection depends on the nature of the rates being displayed to the customer.
The system displays deposit rates in two different modes, a Live Rate mode and an Indicative Rate mode. In the Live Rate mode, rates displayed to the customer are currently available, live rates. When in the Live Rate mode, the selection by the customer causes the system to automatically generate a deal ticket containing the customer selections. The customer can then accept or reject the information contained in the deal ticket. If the customer accepts the trade, the deposit is automatically executed by the system.
The Indicative Rate mode is employed in times when the market is volatile. In the Indicative Rate mode, after the customer submits his selections to the system, a trader at the bank evaluates the customer's selection of currency and tenor and generates a quote for a rate. The quote is then presented to the customer, who then has to acknowledge and accept the trade within a predetermined period of time. If the trade is accepted by the customer, the system automatically executes the accepted deposit request. If the trade is not acknowledged and accepted within the predetermined time period, the trade expires. As can be seen from the above description, an important aspect of the present invention is that the confirmation of the trade occurs online and real time. Once the customer accepts the trade, it is logged.
The system allows the customer to generate customized screens that display the bids (e.g., to display the types of currencies in which the customer is interested). The system has further utilities for the customers to view archives of previous deals, establish profiles and preferences and chat with traders. The system further includes state of the art security in order to ensure the safety and confidentiality of the banking transactions.
BRIEF DESCRIPTION OF THE DRAWINGS
For the purposes of illustrating the present invention, there is shown in the drawings a form which is presently preferred, it being understood however, that the invention is not limited to the precise form shown by the drawing in which:
FIG. 1 illustrates the hardware components of the system of the present invention;
FIG. 2 depicts a user interface presenting live rates to a user;
FIG. 3 is a user interface screen used for generating new rate screens; and
FIG. 4 illustrated a user interface screen containing a rate ticket.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawing figures in which like reference numbers refer to like elements, there is shown in FIG. 1 a diagram of the hardware elements of the system of the present invention, designated generally as “ 100 ”.
System 100 illustrates the system of the present invention that allows customers 110 to use the Internet 115 to obtain real time and indicative quotes for deposits and for making such deposits. Customers 110 use their workstations 110 to connect to system 100 through a communication network 115 . In a preferred embodiment, the network 115 is the public Internet, but can be any other communication connection such as a direct dial up line or a third party value added network. Customer workstations 110 are comprised of any platform capable of running an Internet web browser or similar graphical user interface software. Examples of suitable web browsers include Microsoft's Internet Explorer™ and Netscape's Communicator™. The platform for user workstations 110 can vary depending on the needs of its particular user and includes a desktop, laptop or handheld personal computer, personal digital assistant, web enabled cellular phone, web enabled television, or even a workstation coupled to a mainframe computer.
In the preferred embodiment, customer workstations 110 communicate with system 100 using the Transmission Control Protocol/Internet Protocol (TCP/IP) upon which particular subsets of that protocol can be used to facilitate communications. Examples include the Hypertext Transfer Protocol (HTTP), data carrying Hypertext Mark-Up Language (HTML) web pages, Java and Active-X applets and File Transfer Protocol (FTP). Data connections between customer workstations 110 and data communication network 115 can be any known arrangement for accessing a data communication network, such as dial-up Serial Line Interface Protocol/Point-to-Point Protocol (SLIP/PPP), Integrated Services Digital Network (ISDN), dedicated leased-line service, broadband (cable) access, Digital Subscriber Line (DSL), Asynchronous Transfer Mode (ATM), Frame Relay or other known access techniques. Web server 120 is coupled to data communication network 115 in a similar fashion. However, it is preferred that the link between the web server 120 and data communication network 115 be arranged such that access to the web server 120 is always available.
It should be noted that although customer workstations 110 and the web server 120 are shown as each coupled to a single data communication network 115 , this arrangement is shown merely for the convenience of aiding explanation of the present invention and is not limited to such. For example, data communication network 115 can be the Internet or other public or private network comprised of multiple communication networks, coupled together by network switches or other communication elements. Between the communication network 115 and the web servers 120 of system 100 is a “soft” firewall 117 . Soft firewall 117 is firewall that is erected using only software techniques (as opposed to firewall described below).
Web server 120 is comprised of one or more central processing units coupled to one or more databases (not shown). In addition, web server 120 further comprise a network interface (not shown) to couple the processor to data communication network 115 , and include provisions for a web site or other technology which can create a network presence from which the provider of web server 120 can interact with customer workstations 110 . Technologies including hardware and software for establishing web sites such as an Internet web site are known.
Web server 120 can be comprised of any suitable processor arrangement designed to accommodate the expected number of users and transactions for the particular system in which these elements will be implemented. Known software languages and database technologies can be used to implement the described processes. The databases and programmatic code used by web server 120 are stored in suitable storage devices within, or which have access to, web server 120 . The nature of the invention is such that one skilled in the art of writing computer executable code (software), would be able to implement the described functions using one or more popular computer programming languages such as “C++”, Visual Basic, Java or HTML.
The web server 120 is coupled, through a separate firewall 125 , to application server 130 . The firewall 125 is comprised of both hardware and software components as is well known in the art. Firewall 125 is required to protect the confidential information contained in system 100 illustrated below firewall 125 in FIG. 1 . As implied by its title, the application server 130 is where the applications employed by the web servers 120 reside. Coupled to the application server 130 is a database 135 . Aside from other data, the customer profiles containing the user IDs, passwords and relationship and profile data is stored in database 135 . Although not shown, database 135 can include a suitable database management system processor which operates thereon. In addition, although database 135 is shown as a separate entity in FIG. 1 , it is contemplated that database 135 can be implemented as part of a storage device within the application server 130 , or can even be coupled to application server 130 across a communication link. Database 135 is preferably a multidimensional database that is analyzed using on-line analytical processing (OLAP) tools.
The application server 130 is further shown as coupled to the back office system 140 . As will be further described below, the back office system 140 includes the legacy systems of the financial institution for taking and maintaining deposits. Although not specifically illustrated in FIG. 1 , the back office system contains a number of internal databases and links to external systems. In one aspect of the present invention, these databases and links are used by the system of the present invention to obtain data related to the market for the currencies in which deposits are taken. This data is in turn used in making deposit quotes to customers.
FIG. 2 illustrates the main screen presented to customers by the web server ( 120 in FIG. 1 ) after they have logged onto the server 120 . Along the left hand side of the screen appears the main menu 200 of the system. The main menu 200 contains a number of icons 202 - 208 that represent some of the primary functions available to the customers. “Logout” icon 202 is used by the customer to exit the system when they have completed their operations on the site. When the user first connects to the system, this icon 202 is a “Login” icon that allows the customer to input her user ID and password. As appreciated by those skilled in the art, the use of a user ID and password is one manner in which the security of the site is maintained. Other security measures such as encryption and authentication are used, but shall not be described herein.
Activation of the “Rates” icon 204 causes the system to display a rate table 215 in the main portion of the screen. The customer can define a default rate table to be displayed upon the user's activation of the “Rates” icon 204 . As described further below in connection with FIG. 3 , the user can thereafter generate, save and recall other customized rate tables.
The “Web Log” icon 206 allows the customer to view a list of all of the deposits transacted by the customer using the system of the present invention, i.e., an archive function. The archive function allows the customer to create a query of the deposit database in order to retrieve deposits meeting the customer's criteria. In a simple embodiment, the customer may request all deposits made between two specified dates Additionally, once the records reflecting the queried deposits have been retrieved by the system, the customer is able to generate and export a database spreadsheet file containing the records (e.g., an Excel™ spreadsheet). The spreadsheet file can thus be imported into the customer's systems for internal use by the customer.
Similar to function activated by the “Web Log” icon 206 , the “Session” icon 208 allows the customer to view a list of all of the trades that the customer has executed since logging onto the system. In a preferred embodiment, the session log listing the deposits contains the following fields that are displayed to the customer: the date on which the trade was executed; the time of execution; the type of instrument; the amount of the deposit; the currency of the deposit; the rate; the return; the value date; and the maturity date.
The specific rate table 215 illustrated in FIG. 2 , entitled “SPOT” was previously defined by the customer. As seen on the bottom portion of the main screen, this customer has further defined several other formats of rate tables known as setups 220 . The format for the “SPOT” setup includes a plurality of different rates 230 , for a plurality of different tenors 225 for a plurality of different currencies 235 . The “SPOT” setup, as well as the other setups 220 were created by the customer using a setup function activated by the “New Setup” icon 240 .
Activation of the “New Setup” icon 240 brings up the setup screen illustrated in FIG. 3 . Although, not shown in FIG. 3 , the customer is first asked to name the new setup and to choose the instrument group from a list of groups which the customer is authorized to trade. For example, the customer might have only been authorized to make deposits through the London branch of the bank. Accordingly, this customer may develop new setups that include the rates, tenors and currencies offered by the London branch. The instruments that a customer may trade are stipulated in a previously negotiated agreement between the bank and the customer.
When creating a new setup, the customer first selects a value date 300 . In a preferred embodiment, the value dates 300 selectable by the customer include Today, Tomorrow or Spot. These value dates 300 are displayed in a pull down menu for selection by the customer. The tenor panel 305 includes all of the tenors that the customer is authorized to trade. To select a tenor for display on the setup being created, the customer selects the check box next to the desired tenor. Conversely, if the customer desired to de-select a tenor, a subsequent click on the check box will exclude the tenor from the setup. As previously, described, the tenor is the term for which the deposit will be taken, e.g., for a day, two days, a week or a month.
In order to select a currency to be displayed in the setup, the customer merely clicks on the desired currency in the currency panel 310 . Displayed in the currency panel are all the currencies for which the customer is authorized. These currencies are broken down into Major currencies 315 and Minor currencies 320 . As a customer selects certain currencies, the selected currencies appear in the selected panel 325 . To change the position in which a currency is displayed in the set up, the customer selects the currency in the selection panel 325 and uses the Up and Down buttons to move the currency up or down on the list.
To view the newly created setup, the customer clicks on the Rates check box 330 . This action displays a rate table (see 215 in FIG. 2 for example) that is formatted as designed by the customer. If the customer desires to further modify the setup, she clicks on the Setup check box 335 which returns the customer to the setup screen as illustrated in FIG. 3 . Similarly, if the customer is viewing a previously created setup, she can click on the Setup check box 335 to modify the existing setup. Again, this action will bring up the setup screen of FIG. 3 which allows the customer to modify the format of the existing setup.
When a particular setup is being displayed, the customer can click on the Default icon 340 to set the currently displayed setup as the default setup. The default setup is displayed when the customer first logs onto the system. The Delete icon 345 is used to delete the currently selected (displayed) setup. The Deal Setting icon 350 is used by the customer to customize the display to preferences preferred by the customer. For example, the customer can choose to automatically hide deal tickets when making a trade, automatically size the frame, automatically close deal tickets, present the currency on the display buttons and split the screen horizontally or vertically.
FIG. 4 illustrates the manner in which a customer can make deposits (trades). There are two types of trade modes according to the present invention, Live Rate mode and Indicative Rate mode. The normal trading mode is the Live Rate mode. In the Live Rate mode, the customer can deal on the active and current rates displayed. As further described below, when the customer hits the Submit button 400 , to send a deposit before the rate changes, the request for the deposit is automatically executed at that rate if the amount of the deposit is within the authorized maximum and minimum for that customer. In the Indicative Rate mode, the rates displayed to the customer are informational only. The Indicative Rate mode is used by the bank in times of market volatility when they cannot guarantee a particular rate. As further described below, the customer can still execute trades using the present invention, but must first receive an online quote from a trader at the bank.
In the example illustrated in FIG. 4 , the customer has selected a particular currency 410 for a particular tenor 415 . This selection is made by clicking on the rate 405 where the desired currency 410 and tenor 415 intersect. In this particular example, the customer has selected the currency as U.S. Dollars at a tenor of one business day which is offered by the bank at a rate 405 of 6.4375. Once the customer has selected this rate 405 , the system automatically displays the deal ticket 420 .
The deal ticket 420 is automatically filled out using certain information derived from the customer's selection. The Rate field 455 is automatically filled out by the system in response to the customer's selection of a interest rate. The date for the Value Date 425 is taken from the rates display selection by the customer. In this particular example, the Value Date 425 is Spot and the actual calendar date is displayed in this field 425 . The Instructions field 430 defaults to the standard instructions that the customer has agreed to with respect to the taking of the deposit. Alternative settlement instructions can be established between the customer and the bank, and these alternative instructions are selectable through the drop down menu associated with the Instructions field 430 . The Maturity Date field 435 is automatically calculated and displayed in response to the value date and tenor previously selected by the customer. The Instructions field 440 defaults to the standard instructions that the customer has agreed to with respect to the maturity of the deposit. Alternative maturity instructions can be established between the customer and the bank, and these alternative maturity instructions are selectable through the drop down menu associated with the Instructions field 440 . In a further embodiment, changes to both the settlement instructions or maturity instructions can be made “on the fly”. In this alternative embodiment, once the Value Date 425 , Maturity Date 430 and Instruction 430 , 440 fields have been automatically filled out, they can be modified by the customer. Each modification will most likely change the values in the other fields. For example, if the customer changes the Maturity Date 430 from one week to one month, the Rate 455 will most likely change. When the customer makes changes, the system performs integrity checks to ensure that the data is consistent. For example, if the customer changes the Value date 425 to Tomorrow, then the system does not allow a Maturity Date 430 of Tomorrow and requires the customer to change at least one of the selections.
In addition to the fields on the deal ticket automatically filled out by the system, the customer must manually fill out certain fields. The first of these fields is the account 525 to which the trade should apply. The drop down menu associated with the Account field 525 allows the customer to select a different account. Furthermore, by activating the Split button 500 , the customer is permitted to designate several accounts to which the deal will apply. When splitting a deposit among more than one account, the customer must designate the amount of the deposit that is to be allocated to each account. The total amount of the deposit is automatically calculated and displayed in the Principal field 450 . With the Principal field 450 filled in, the system automatically calculates the Principal and Interest 460 and the Interest 470 .
In one embodiment of the present invention, the Rate 455 in the Deal Ticket 420 is not automatically updated by the system. Therefore, if the deal ticket 420 has been displayed for a long period of time, the rate displayed in Rate Field 455 is possibly not the rate currently being offered by the bank. In order to insert the latest rate into the Rate field 455 , the customer may select Latest button 485 . One reason for requiring the customer to update this field to prevent a customer from holding open a favorable interest rate on the chance that the interest rate will go down during the course of the day. Once the customer has completed all the required fields and is satisfied with the deal, the customer clicks on the Submit button 400 in order to send the deposit request to the bank. The system will first prompt the user to verify that she wishes to submit the deal for execution. Assuming the customer confirms that she desires to submit the deal, it is then processed to ensure that the deal is within all of the parameters set up between the customer and the bank. One of the checks performed on the data contained in the deal ticket 420 is to ensure that the rate has not changed since the deal ticket 420 was filled out. If the deal is in conformance with the standard parameters previously agreed to by the customer and the bank, the system then prompts the customer to confirm the deal by clicking on the Accept button 490 . Once the customer as confirmed the acceptance of the deal, the deposit request is sent to the back office of the bank where it is booked. Once booked, the status line 475 is updated to indicate “Deal logged” which means that the deposit request has been executed by the bank.
If the deal is outside of the customer's parameters, if the rate has changed or if there are special instructions, the deal submitted by the customer is sent to a trader at the bank for verification and pricing. Once the trader has updated the deal ticket (e.g., with the current rate) the system redisplays the deal ticket 420 with the corrected data (e.g., a new rate in Rate field 455 ). The system will furthermore display a message in the Status area 475 requesting that the customer acknowledge the new deal (e.g., the new rate). To acknowledge the new deal the customer simply clicks on the Acknowledge button 480 . The customer is then required to click on either the Accept 490 or Reject 495 buttons to respectively accept or reject the new deal.
If the problem cannot be resolved by the trader at the bank without talking to the customer, the trader can communicate directly with the customer using the Chat feature 510 . This feature allows the customer and the trader to interactively communicate in a chat window (not shown). The customer can initiate a communication with a trader by selecting the Chat box 510 . In this communication window (not shown) the customer can ask questions of the trader and the trader is be able to provide answers directly to the customer.
The previous discussion has detailed the Live Rate mode in which the actual rates are presented to the customer on the display. The Indicative Rate mode will now be discussed. As previously described, the Indicative Rate mode is employed in times of market volatility when the bank is unable to present live rate quotes to its customers in the above described rate table. When operating in the Indicative Rate mode, the system will present rates to the customer that are indicative of the rates that the customer can expect to be quoted by the bank. The rate is informational only, and does not represent a commitment by the bank to accept a deposit at that rate. As seen in FIG. 4 , the system indicates that it is presenting live or indicative rates in area 550 of the rate table. If the rates are live rates, area 550 will include a “Live” indication, if the rates are indicative, area 550 will say “Indic.” The same setups, as previously described with respect to FIG. 3 , are used for both Live and Indicative Rate modes.
In the Indicative Rate mode, the customer selects a rate as described above and the system present a deal ticket 420 to the customer. The customer fills out the principle amount 450 and changes any other fields on the deal ticket 420 as describe above. When the customer is satisfied with the terms of the deposit request, she clicks on the Submit button 400 and the request for the deposit is forwarded to a trader at the bank. As previously described the deposit request includes the value date 425 , the tenor 415 and the currency 410 . The trader evaluates the value date 425 , the tenor 415 and the currency 410 as requested by the customer and develops a rate to bid to the customer.
The trader at the bank presents the bid to the customer through the deal ticket 420 . When the deal ticket 420 is updated with the bid, a message is displayed in the status area 475 that reads “ACKNOWLEDGE NEW RATE.” The customer must acknowledge the bid using the Acknowledge button 485 . Once the customer has acknowledged the bid, a time appears in the Timeout area 560 . The time presented in this area 560 is the time left that the customer has to accept the bid. In a preferred embodiment, the time is measured in seconds. The time decrements until either the customer accepts or rejects the bid, or time runs out, in which case the bid from the bank expires. If the time in Timeout area 560 reaches zero before the customer has accepted the bid, the status area 475 is updated to read “PRICE WITHDRAWN” but the deal ticket 420 is not closed. In a preferred embodiment, the timeout begins when the customer acknowledges the deal.
The customer can expressly reject the bid by activating the Reject button 495 . If the customer has any questions about the bid, the customer can initiate communication with the trader using the Chat feature 510 as previously described. If a chat takes place, the bid will most likely expire (timeout) and the customer will have to submit a new deposit request to which the trader will respond with another bid.
If the customer is satisfied with the bid, and the time in Timeout area 560 has not expired, the customer can accept the bid by selecting the Accept button 490 . The accepted bid is transmitted to the back office of the bank where it is booked. Again, the acceptance by the customer of the deal acts as confirmation of the deal. The status line 475 is updated to indicate “Deal logged” which means that the deposit request has been executed by the bank.
As described above, the method and system of the present invention provides customers with complete information regarding deposit rates and options in an efficient and convenient manner right on the customer's desktop. The invention further allows the customer to automatically execute trades with respect to deposits without the need for interacting with bank traders and without the time consuming and error prone confirmation process of the prior art. The invention thus provides a valuable tool for liquidity management.
The invention enables customers to view the bank's current deposit rates and place deposits simply clicking on the Graphical User Interface (GUI) of the present invention. The deposits can be negotiated in any currency for which the customer has standing settlement instructions with the bank. In the Live Rate mode, the customer can view and place deposits without any interaction with bank personnel. In the Indicative Rate mode, the bank trader presents a bid to the customer's desktop that will be automatically processed once acknowledged and accepted by the customer. The customers, if so desired, can communicate with the bank traders using the chat feature of the present invention. The customers can furthermore display, sort and export a list of the all of the deposit transactions made using the present invention.
As appreciated by those skilled in the art, the present system can be integrated with other systems maintained by a financial institution or bank to provide seamless service to its customers. For example, the system can be coupled to the bank's foreign exchange system such that the customer can have it's deposits converted into a different currency before the deposit is taken. Similarly, the deposit taking system of the present invention can be coupled to the payment system of the bank such that the proceeds from the receipt of a payment are fed directly into the deposit taking system. Conversely, a payment can be made though the bank's payment system using funds that are maturing from a deposit taken by the system of the present invention.
Although the present invention has been described in relation to particular embodiments thereof, many other variations and other uses will be apparent to those skilled in the art. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein, but only by the gist and scope of the disclosure. | A system and method for initiating and processing banking deposits. In a preferred embodiment, the system is maintained by a financial institution such as a bank and the bank's customers access the system through the Internet. The system provides a Graphical User Interface that allows the customers to view the bank's current rates for a plurality of currencies and a plurality of time periods. The customer selects the desired rate on the interface and the system automatically generates a deal ticket that is presented to the customer. The customer submits the deal ticket for trading. A confirmation of the trade occurs online and real time. The system has further utilities for the customers to view archives of previous deals, establish profiles and preferences and chat with bank representatives. The system further includes state of the art security in order to ensure the safety and confidentiality of the banking transactions. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for use in combination with a magnetic resonance imaging apparatus, which can be inserted into a body cavity and which detects a magnetic resonance signal in the cavity and supplies the signal to the imaging apparatus so that the apparatus may form a magnetic resonance image for diagnostic use.
2. Description of the Related Art
A magnetic resonance imaging apparatus for receiving a magnetic resonance signal generated in a body cavity is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 6-269421. This apparatus is used in combination of a device which is similar in structure to an ordinary endoscope.
The device comprises a distal end section, an insertion section, an operating section and a universal cord. The distal end section comprises a high-frequency coil, a container, a bending portion and an optical system. The high-frequency coil detects a magnetic resonance signal. The container contains the coil. The optical system has an observation unit and an illumination unit. The distal end section has holes through which forceps can be inserted into and removed from a body cavity and through which liquids can be applied into and removed from the body cavity. The insertion section and the universal cord are covered with an outer sheath which is a flexible tube. The operation section has means for controlling the bending of the bending portion and air supply and water supply through the holes of the distal end portion. The operation section has holes through which forces and other medical instruments can be guided into a body cavity.
When used in combination with the device, the magnetic resonance imaging apparatus can provide an endoscope image and a magnetic resonance image, which are examined to make diagnosis.
The device disclosed in Publication No. 6-269421 is disadvantageous, however, in that its components used in an intense static magnetic field do not have appropriate magnetic permeabilities or magnetic susceptibilities. If the components constituting the flexible tube are made of material having high magnetic permeabilities, they will be attracted to the magnet of the magnetic resonance imaging apparatus, inevitably resulting in an inconvenience in use. Further, these components will impair the uniformity of the static magnetic field generated by the magnet, ultimately deteriorating the MR image.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a device for use in combination with a magnetic resonance imaging apparatus, which does not adversely influence the MR image formed by the apparatus, which is not attracted to the magnet of the apparatus, thereby ensuring high safety for operators and patients and having high operability, and which can reliably detect magnetic resonance signals from living tissues.
According to a first aspect of the invention, there is provided a device which is designed for use in combination with a magnetic resonance imaging apparatus and which has a distal end section which can be inserted into a body cavity. The device comprises a first portion and a second portion. The first portion has at least one of a magnetic permeability and a magnetic susceptibility which has such a value that diagnosis and treatment are not influenced by a magnetic resonance image distorts caused by disturbance in the uniformity of the static magnetic field generated by the apparatus. The second portion has at least one of a magnetic permeability and a magnetic susceptibility which is higher than that of the distal end section and is of such a value that the second portion is not attracted to the static magnetic field.
According to a second aspect of the invention, there is provided a device which is designed for use in combination with a magnetic resonance imaging apparatus and which has a distal end section which can be inserted into a body cavity. The device comprises a first portion, a second portion and a third portion. The first portion can enter a region to be imaged by the apparatus and has at least one of a magnetic permeability and a magnetic susceptibility which has such a value that diagnosis and treatment remain not influenced by a magnetic resonance image distorted due to disturbance in the uniformity of the static magnetic field generated by apparatus. The second portion cannot enter a body cavity and has at least one of a magnetic permeability and a magnetic susceptibility which is higher than that of the distal end section and has such a value that the second portion is not attracted by the static magnetic field. The third portion cannot enter the region to be imaged, can enter the body cavity, and has at least one of a magnetic permeability and a magnetic susceptibility which is higher than that of the first portion and lower than that has the second portion and of such a value that disturbances in the uniformity of the static magnetic field are small.
Since the device does not disturb the uniformity of the static magnetic field while a subject is being examined or is receiving treatment, the parts of the subject, being examined or receiving treatment can be observed in the form of MR images which are not distorted. Further, non-attraction to the static magnetic field ensures high safety for an operator and the subject and has high operability. Moreover, since it is only the distal end section that needs to have a magnetic permeability which is too small to deteriorate MR images, the device is simple in structure and can be manufactured at low cost.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention.
FIGS. 1A, 1B and 1C are views schematically showing the structure of a device according to first, second and third embodiments of the present invention;
FIGS. 2A, 2B and 2C are views schematically showing the structure of a device according to fourth, fifth and sixth embodiments of the present invention;
FIGS. 3A, 3B and 3C are views schematically showing the structure of a device according to seventh, eighth and ninth embodiments of the present invention;
FIG. 4 is a view schematically showing the structure of a device according to tenth to twelfth embodiments of the present invention;
PIGS. 5A and 5B are views schematically showing the structure of a device according to thirteenth to fifteenth embodiments of the present invention;
FIG. 6 is a view schematically showing the structure of a device according to sixteenth to eighteenth embodiments of the present invention;
FIGS. 7A and 7B are views schematically showing the structure of a device according to nineteenth to twenty-first embodiments of the present invention;
FIGS. 8A and 8B are views schematically showing the structure of a device according to twenty-second, twenty-third, and twenty-fourth embodiments of the present invention;
PIG. 9 is a view schematically showing the structure of a device according to a twenty-fifth embodiment of the present invention;
FIG. 10 is a view schematically showing the structure of an injection needle according to a twenty-sixth embodiment of the present invention;
FIG. 11 is a view schematically showing the structure of forceps according to a twenty-seventh embodiment of the present invention;
FIG. 12 is a view schematically showing the structure of a pressure emission element according to a twenty-eighth embodiment of the present invention;
FIG. 13 is a view schematically showing the structure of a treatment electrode according to a twenty-ninth embodiment of the present invention;
FIG. 14 is a view schematically showing the structure of a rigid scope according to a thirty-first embodiment of the present invention; and
FIG. 15 is a view schematically showing the structure of a rigid scope according to a thirtieth embodiment of the present invention.
DETAILED DESCRIPTION
First Embodiment
FIGS. 1A, 1B and 1C schematically show the structure of a device for a magnetic resonance imaging apparatus according to the first embodiment of the present invention. In these figures, FIG. 1A shows the entire device, FIG. 1B is a cross-section cut along a line A--A of FIG. 1A, and FIG. 1C is a cross section cut along a line C--C of FIG. 1A.
In this first embodiment, an insertion portion 20 of the device can be inserted into body cavities of a patient and is formed of at least one layer of a flexible tube 21. A distal end portion 23 is provided at the top end of the insertion portion 20. The distal end portion 23 comprises of a cylindrical container member made of a material having a low dielectric constant, and particularly, the top end of the portion 23 is enclosed to be round. As shown in FIG. 1B, a magnetic resonance signal receiver coil (portion) 24 having a loop-like shape as a receiver coil means for receiving a magnetic resonance signal and a rectifier circuit 25 are included in the distal end portion 23. Further, a transmit means 26 for transmitting a magnetic resonance signal received by the magnetic resonance signal receiver coil 24 is provided in the tube 21 of the insertion portion 20. The transmit means 26 transmits the magnetic resonance signal to the magnetic resonance signal output portion 27.
The magnetic resonance signal output portion 27 is provided at a bottom end of the insertion portion 20. The magnetic resonance signal output portion 27 has a function as a connector to the magnetic resonance imaging apparatus (MRI) coupled with the device, so that the output portion 27 outputs the magnetic resonance signal received by the distal end portion 23 to the magnetic resonance imaging apparatus.
The material of a first portion which forms the distal end portion 23 in the device body has a magnetic permeability or magnetic susceptibility which is lower than that of the tube 21 of the insertion portion forming a second portion as a remaining other portion of the device body and that of a material forming the magnetic resonance signal output portion 27 and is within such a range that does not disturb the uniformity of a static magnetic field generated by the magnetic resonance imaging apparatus. Specifically, the first portion forming the distal end portion 23 is made of a material which has such a magnetic permeability or magnetic susceptibility that causes only a negligible disturbance in uniformity of the static magnetic field so that a distortion of a magnetic resonance cross-section image resulting from the disturbance is considered as not influencing on a diagnosis or a treatment.
As a typical example which provides a distinguishable magnetic permeability or magnetic susceptibility as stated above, there may be a distal end portion 23 made of an material having a extremely small magnetic susceptibility such as a resin, a non-magnetic metal, or the like, when a low magnetic permeability metal or a low magnetic susceptibility metal having a feeble magnetism is included in materials forming the insertion portion 20 and magnetic resonance signal output portion 27.
In addition, the shape of the distal end portion is not limited to that specified above, as long as the requirements also specified above are satisfied. The shape of the magnetic resonance signal receiver coil 24 is not limited to a loop-like shape. The material of the magnetic resonance signal receiver coil 24 is not limited to gold, silver, copper, and aluminum, as long as it is a low magnetic permeability metal which is electrically conductive. Further, the shape and lay-out of components inside the distal end portion 23 are not limited to the structure as specified above.
As has been explained above, according to the first embodiment of the present invention, an insertion portion 20 of the device is inserted into a body and the distal end portion 23 is precisely positioned at a target portion. After the insertion, a magnetic resonance signal received by a magnetic resonance signal receiver coil 24 included in the distal end portion 23 is transmitted to a magnetic resonance imaging apparatus not shown through a transmit means 26 and a magnetic resonance signal output portion 27 connected thereto, and accordingly, an MR-image is obtained. An operator carries out a diagnosis on the basis of the MR-image.
Thus, in the structure of this embodiment, the insertion portion 20 can be easily inserted into body cavities, thereby incurring less burdens onto a patient's body, and the insertion portion 23 can be precisely positioned at a target portion.
Further, if the insertion portion of this device is inserted into a body, uniformity in the static magnetic field in the area whose MR-image is being picked up can be maintained so that distortions do not appear on the MR-image since the material forming the periphery of the magnetic resonance signal receiver coil 24 has an extremely small magnetic susceptibility in the vicinity of the coil 24. This means that magnetic resonance signals can be received directly from the body cavities, and that clear MR-images can be obtained without deterioration in image quality since the distal end portion 23 inserted into a body does not disturb the magnetic field.
If a structure of an endoscope is incorporated in this device, the device further has a structure as a soft scope so that observation using the endoscope function can simultaneously be carried out. The material of the structure of the endoscope must naturally be considered as having the same magnetic susceptibility as stated above.
Second Embodiment
This second embodiment has a structure of the same type as the first embodiment. In this embodiment, the material forming the distal end portion 23 provided at the top end of the flexible tube 21 constituting the insertion portion 20 of the device for a magnetic resonance imaging apparatus has a magnetic permeability lower than that of the material forming the insertion portion 20 and the magnetic resonance signal output portion. The distal end portion 23 can be inserted into a body and is a first portion which enters into at least the area to be picked up by the magnetic resonance imaging apparatus. The magnetic resonance signal output portion 27 is a second portion which cannot be inserted into the body.
Further, a portion forming the tube 21 constituting the insertion portion 20 is a third portion which does not enter into the area to be picked up by the magnetic resonance imaging apparatus but can be inserted into the body. The material of this third portion has a magnetic permeability lower than that of the material forming the magnetic resonance signal output portion 27 which cannot be inserted into the body. Specifically, the magnetic susceptibility of this third portion is a value between the magnetic susceptibility of the first portion and the magnetic susceptibility of the second portion, within such a range which causes only a small disturbance in the static magnetic field generated by the magnetic resonance imaging apparatus. As a typical example of this, there may be an insertion portion 20 made of titanium, titanium alloy, austenite-based stainless steel or the like which is slightly magnetized by means of some treatments or the like, and a distal end portion made of resins, copper, copper alloy, aluminum alloy, or titanium or titanium alloy which has a negligibly small magnetic susceptibility, when low magnetic permeability metal or low magnetic susceptibility metal having a feeble magnetism is included in the materials forming the magnetic resonance signal output portion 27 corresponding to a portion having a shape and arranged at a position which cannot be inserted into a body.
The distal end portion may be made of copper (magnetic susceptibility χ=-0.0086×10 6 ), copper alloy having similar magnetic susceptibility, resin, titanium, titanium alloy or aluminum (χ=0.61×10 6 ). The insertion portion which can be inserted into a body cavity but is not moved to an imaging region may be made of any one of these materials and worked upon to be magnetized. The portion which can be inserted into a body cavity may be made of SUS304 which is austenite-based stainless steel (magnetic permeability μ=1.0037) or SUS310 which is also austenite-based stainless steel (annealed, magnetic permeability μ=1.0018). The insertion portion can be made of either SUS304 or SUS310 under the nomination of the JIS.
The material specified above which have the magnetic susceptibilities and permeabilities mentioned are no more than a few examples. The distal end portion, the insertion portion, and the portion able to enter a body cavity can be made of other materials which exhibit magnetic susceptibilities and permeabilities different from those mentioned above.
In addition, the shapes of components are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the magnetic resonance signal receiver coil 24 is not limited to a loop-like shape. The material of the magnetic resonance signal receiver coil 24 is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive. Further, the insertion portion 20 uses a material which has the lowest magnetic permeability if necessary, as long as the material does not influence an MR-image.
The second embodiment having the above structure attains the same operation as the first embodiment. Therefore, according to the this embodiment, the same advantages as shown in the first embodiment can be obtained. Further, since not only the distal end portion 23 but also the insertion portion 20 are not attracted by a magnet of a magnetic resonance video device and the magnetism of the insertion portion 20 does not cause such influences which disturb the static magnetic field in the area whose MR-image is being picked up, distortions of the MR-image is eliminated and safety can be ensure for both of an operator and a patient.
Third Embodiment
This third embodiment has a structure of the same type as the first embodiment. In this embodiment, however, the material forming the distal end portion 23 of the device for a magnetic resonance imaging apparatus has a magnetic permeability lower than that of the material forming the insertion portion 20 and the magnetic resonance signal output portion. In addition, the material forming the insertion portion 20 has a magnetic permeability lower than that of the material forming the magnetic resonance signal output portion 27. Further, the material forming the magnetic resonance signal output portion 27 has a magnetic permeability equal to or lower than metallic materials forming a conventional endoscope operating portion.
Shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the magnetic resonance signal receiver coil 24 is not limited to a loop-like shape. The material of the magnetic resonance signal receiver coil 24 is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive. Further, the insertion portion 20 uses a material which has the lowest magnetic permeability if necessary, as long as the material does not influences an MR-image.
The second embodiment having the above structure attains an advantage in that the magnetic resonance signal output portion 27 is not attracted by a magnet of a magnetic resonance video device so that safety can be ensured for both of an operator and a patient, in addition to the advantages as explained in the first and second embodiments.
Fourth Embodiment
FIGS. 2A, 2B and 2C schematically show the structure of a device for a magnetic resonance imaging apparatus according to the fourth embodiment of the present invention. In these figure, FIG. 2A shows the entire device, FIG. 2B is a cross-section cut along a line 2B--2B of FIG. 2A, and FIG. 2C is a cross section cut along a line 2C--2C of FIG. 2A.
In this fourth embodiment, an insertion portion 20 of the device has a structure basically common to the first embodiment. However, the tube 21 which can be inserted into body cavities and is formed of at least one layer is not flexible but is a rigid tube.
According to the fourth embodiment having the structure as stated above, since the tube 21 constituting the insertion portion 20 is hard, the insertion portion 20 is useful when it is inserted into a body, especially, into a ventricle, a pleural cavity, a joint, or a peritoneal cavity, and the distal end portion 23 can be precisely positioned at a target portion. Further, according to this embodiment, a tube can be easily inserted into a body, particularly into a ventricle, a pleural cavity, a joint, or a peritoneal cavity. The other operation and advantages are the same as those of the first embodiment described above.
If a structure of an endoscope is incorporated in this device, the device further has a structure as a rigid scope so that observation using the endoscope function can simultaneously be carried out. The material of the structure of the endoscope must naturally be considered as having the same magnetic susceptibility as stated above.
Fifth Embodiment
This second embodiment has a structure similar to the fourth embodiment, except that, the material forming the distal end portion 23 of this embodiment has a magnetic permeability lower than that of the material forming the insertion portion 20 and the magnetic resonance signal output portion 27.
Further, the material forming the insertion portion 20 has a magnetic permeability lower than that of the material forming the magnetic resonance signal output portion 27. As a typical example of this, there is an insertion portion 20 made of resins, copper, copper alloy, or aluminum alloy, when iron having a high purity is included in the material forming the magnetic resonance signal output portion 27.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the magnetic resonance signal receiver coil 24 is not limited to a loop-like shape. The material of the signal receiver coil 24 is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The fifth embodiment having the above structure attains the same operation as the fourth embodiment. Therefore, according to this embodiment, the same advantages as shown in the first embodiment can be obtained. Further, according to this fifth embodiment, not only the distal end portion 23 but also the insertion portion 20 is not attracted by a magnet of a magnetic resonance video device, so that safety can be ensured for both of an operator and a patient.
Sixth Embodiment
This sixth embodiment has the same structure as the first embodiment, except as to the following respect. Specifically, the material forming the distal end portion 23 has a magnetic permeability lower than those of the materials forming the insertion portion 20 and the magnetic resonance signal output portion 27, and the material forming the insertion portion 20 has a magnetic permeability lower than that of the material forming the magnetic resonance signal output portion 27. Further, the material forming the magnetic resonance signal output portion 27 has a magnetic permeability equal to or lower than metallic materials forming a conventional endoscope operating portion.
The sixth embodiment having the above structure performs the same operation as that of the fourth embodiment described above. Further, according to the this embodiment, an advantage is obtained in that the magnetic resonance signal output portion 27 is not attracted by a magnet of a magnetic resonance imaging apparatus so that safety can be ensured for both of an operator and a patient, in addition to the advantages as explained in the fifth embodiment.
Seventh Embodiment
FIGS. 3A, 3B and 3C schematically show the structure of a device 31 for a magnetic resonance imaging apparatus according to the seventh embodiment of the present invention. In these figure, FIG. 3A shows the entire device, FIG. 3B shows an example of the frame structure of a bend portion which will be explained later, and FIG. 3C is a cross-section cut along a line E--E of FIG. 3B.
In this seventh embodiment, the device 31 which can be inserted into body cavities includes an insertion portion comprising of a flexible tube, a distal end portion 33, and a magnetic resonance signal output portion 34, like in the first embodiment, and further includes a bend portion 35 inserted between the insertion portion 32 and the distal end portion 33. A main body member 36 of the magnetic resonance signal output portion 34 is provided at a bottom end of the insertion portion 32. The main body member 36 is provided with an operating means for controlling the bending of the bend portion 35.
The frame of the bend portion 35 is arranged as shown in FIGS. 3B and 3C. This frame of the bend portion comprises a plurality of short tube-like frame pieces 38, junction portions 39 including pins for pivot-connecting adjacent frame pieces 38, wires 40a for rotating adjacent frame pieces 38 around the junction portions 39 as fulcrums, thereby to bend the entire bending portion 35, and wire receivers 41a through which the wires 40a penetrate. Two wires 40a are provided respectively at upper and lower positions, and therefore, two wire receivers are provided at upper and lower positions, too. In the insertion portion 32, the wires 40a are guided to an operating means 37 incorporated in the main body member 36 of the magnetic resonance signal output portion 34. However, the number of wires 40a is not limited to two. As an outer layer of the frame of the bend portion, a cylindrical net made of natural or artificial fibers may be used, and further, an upper coating member made of elastomer may be provided as an upper outer layer over the outer layer.
In this structure, the material forming the distal end portion 33 has a magnetic permeability lower than those of the materials forming the bend portion 35, the insertion portion 32, the operating means 37, and the magnetic resonance signal output portion 34. As a typical example of this, there may be a distal end portion 33 made of resins when iron having a high purity is included in the materials forming the insertion portion 32, the bend portion 35, the magnetic resonance signal output portion 34, and the operating portion 37.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the receiver coil 24 is not limited to a loop-like shape. The material of the signal receiver coil 24 is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive. In addition, an elastomer for an outer layer of the bend portion may be made of natural or synthesized high polymer.
According to the seventh embodiment having the above structure, the insertion portion 32 is firstly inserted into a body cavity while adjusting the bend portion 35 by means of the operation means 37, and the distal end portion 33 is precisely positioned at a target portion. Further, the operation of a bend system is performed in such a manner in which the wires 40a are pulled by the operating means 37 connected to the wires 40a, and the frame pieces 38 are thereby rotated by a small angle with the junction portions 39 of the frame pieces 38 as their fulcrums. Thus, the bend portion 35 is bent. After insertion of the portion 32, the operation of the seventh embodiment is the same as that of the first embodiment.
This embodiment attains an advantage in that the insertion portion can be inserted more easily into to a patient and the distal end portion 33 can be precisely positioned at a target portion.
If a structure of an endoscope is incorporated in this device, the device further has a structure as a flexible scope so that observation using the endoscope function can simultaneously be carried out. The material of the structure of the endoscope must naturally be considered as having the same magnetic susceptibility as stated above.
Eighth Embodiment
This eighth embodiment has a structure similar to the seventh embodiment shown in FIGS. 3A, 3B and 3C except for the following difference. Specifically, in the device 31 for a magnetic resonance imaging apparatus according to the eighth embodiment, the materials forming the distal end portion 33 and the bend portion 35 have magnetic permeabilities lower than those of the materials forming the operating portion 32 and the magnetic resonance signal output portion 34. Further, the material forming the insertion portion 32 has a magnetic permeability lower than those of the materials forming the operating means 37, the main body member 36 including said means, and the magnetic resonance signal output portion 34. As a typical example of this, the distal end portion 33, the bend portion 35, and the insertion portion 32 are made of resins, when iron having a high purity is included in the materials forming the insertion portion 32, the operating means 37, and the magnetic resonance signal output portion 38.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the magnetic resonance signal receiver coil 24 is not limited to a loop-like shape. The material of the signal receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The eighth embodiment having the above structure attains the same operation as the seventh embodiment. Therefore, according to this embodiment, the same advantages as obtained in the seventh embodiment can be attained. Further, according to this eighth fifth embodiment, not only the distal end portion 33 and the bend portion 35 but also the insertion portion 32 is not attracted by a magnet of a magnetic resonance video device, so that safety can be ensured for both of an operator and a patient.
Ninth Embodiment
This ninth embodiment has the same structure as the seventh embodiment shown in FIGS. 3A, 3b and 3C, except the following respect.
In the device 31 for a magnetic resonance imaging apparatus, the materials forming the distal end portion 33 has a magnetic permeability lower than those of the materials forming the insertion portion 32 and the magnetic resonance signal output portion 34, and the material forming the insertion 32 has a magnetic permeability lower than that of the material forming the magnetic resonance signal output portion 34.
Further, the materials forming the magnetic resonance signal output portion 34 and the operating means 37 have magnetic permeabilities equal to or lower than those of metallic materials forming a conventional endoscope operating portion.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the signal receiver coil is not limited to a loop-like shape. The material of the signal receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The ninth embodiment having the above structure performs the same operation as that of the seventh embodiment described above. According to this embodiment, an advantage is obtained in that the entire insertion portion 32 is not attracted by a magnet so that safety can always be ensured for both of an operator, an assistant operator, and a patient, in addition to the advantages obtained in the fifth embodiment.
Tenth Embodiment
FIGS. 4 schematically show the structure of a device 31 for a magnetic resonance imaging apparatus according to the tenth embodiment of the present invention. In this embodiment, the structures of the bend portion 35 and the distal end portion 33 are the same as those used in the fourth and seventh embodiments. In this embodiment, the device 31 comprises a distal end portion 33 having the same structure as in the fourth embodiment, an insertion portion 32 which is made of a hard tube and can be inserted into a body, a bend portion 35 having the same structure as in the seventh embodiment, a magnetic resonance signal output portion 34 for outputting a magnetic resonance signal received by the distal end portion 33 to the magnetic resonance imaging apparatus coupled with the device, and an operating means used to bend the device.
In this structure, the material forming the distal end portion 33 has a permeability lower than those of the materials forming the bend portion 35, the insertion portion 32, the magnetic resonance signal output portion 34, and the operating means 37.
As a typical example, the insertion portion 33 may be formed of resins when iron having a high purity is included in the materials forming the insertion portion 32, the bend portion 35, the magnetic resonance signal output portion 34, and the operating means 37.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the receiver coil is not limited to a loop-like shape. The material of the coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
According to the tenth embodiment having the above structure, the device is inserted into a body, particularly into a ventricle, a pleural cavity, a joint, or a peritoneal cavity, while bending it if necessary, and the distal end portion 33 is precisely positioned at a target portion. The operation of the bend portion is the same as that of the seventh embodiment. Also, the operation after insertion of the device is the same as the seventh embodiment.
According to the this embodiment, another advantage is obtained in that the device can be inserted into a body, particularly into a ventricle, a pleural cavity, a joint, or a peritoneal cavity while bending the device if necessary, and the distal end portion can be precisely positioned at a target portion, in addition to the advantages obtained in the first embodiment.
Eleventh Embodiment
This eleventh embodiment has a structure similar to the tenth embodiment shown in FIG. 4 except for the following difference. Specifically, in the device 31, the materials forming the distal end portion 33 and the bend portion 35 have magnetic permeabilities lower than those of the materials forming the insertion portion 32, the magnetic resonance signal output portion 34, and the operating means 37.
Further, the material forming the insertion portion 32 forming part of an intermediate member of the body of the device has a magnetic permeability lower than those of the materials forming the operating means 37 and the magnetic resonance signal output portion 34 which form part of a handling side portion of the body of the device. As a typical example of this, the distal end portion 33, the bend portion 35, and the insertion portion 32 are made of resins, when iron having a high purity is included in the materials forming the operating portion 37 and the magnetic resonance signal output portion 34.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the receiver coil is not limited to a loop-like shape. The material of the receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The eleventh embodiment having the above structure attains the same operation as the tenth embodiment explained above. Further, according to the this embodiment, another advantage is obtained in that not only the distal end portion 33 but also the bend portion 35 and the insertion portion 32 are not attracted by a magnet of a magnetic resonance imaging apparatus, so that safety can be ensured for both of an operator and a patient during use of the device 31, in addition to the same advantages as obtained in the tenth embodiment.
Twelfth Embodiment
This twelfth embodiment is based on the same structure as the tenth embodiment shown in FIG. 4, and is further characterized in the following respect. The materials forming the distal end portion 33 and the bend portion 35 have permeabilities lower than those of the materials forming the insertion portion 32, the operating means 37, and the magnetic resonance signal output portion 34. The material forming the insertion portion 32 has a permeability lower than the operating means 37 and the magnetic resonance signal output portion 34 in the handling side.
Further, the materials forming the operating means 37 and the magnetic resonance signal output portion 34 have magnetic permeabilities equal to or lower than those of metallic materials forming a conventional endoscope operating portion.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the signal receiver coil is not limited to a loop-like shape. The material of the signal receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The twelfth embodiment having the above structure operates in the same manner as in the tenth embodiment described above. According to this embodiment, another advantage is obtained in that the entire device is not attracted by a magnet so that safety can always be ensured for an operator, an assistant operator, and a patient, including the time when the device is used, in addition to the advantages obtained in the eleventh embodiment.
Thirteenth Embodiment
FIGS. 5A and 5B schematically show the structure of a device for a magnetic resonance imaging apparatus according to the thirteenth embodiment of the present invention. In these figures, FIG. 5A is a perspective view showing the entire device, and FIG. 5B shows an example of the frame structure of a bend portion.
In this embodiment, an insertion device 40 made of a tube comprises a distal end portion 41 having an opening for an optical system and a conduit system both not shown, a signal receiver coil container portion 42 having the same structure as the distal end portion of the first embodiment, and an insertion portion 43 which is made of a flexible tube and can be inserted into a body cavity. Further, a handling side portion 44 which is always kept outside the body is provided at a bottom end of the insertion portion 43. The handling side portion 44 includes a forceps opening 45, an eye-piece portion 47 having an eye-piece optical system 46, and a retaining portion 48 provided between the forceps opening 45 and the eye-piece portion 47. Further, the handling side portion 44 is connected with a universal cord 49 in which an illumination optical system and a magnetic resonance signal transmission system are inserted. An extended top end of the universal cord 49 is provided with a connector 50 for receiving illumination light from a light source not shown, and a magnetic resonance signal output portion 51 for outputting a magnetic resonance signal received by the container portion 42 to a magnetic resonance imaging apparatus coupled with the device but not shown in the figure.
As shown in FIG. 5B, a flexible tube constituting the insertion portion 43 comprises a bend member 54 which is made of metal or non-metal and has a spiral structure which allows a frame member to be flexible, a cylindrical net 55 made of metal or resins which covers the outer layer of the bend member, and a coating member 56 as an uppermost outer layer made of natural or synthetic resins.
In this structure, the material forming the container portion 42 has a permeability lower than those of the materials forming the distal end portion 41, the insertion portion 43, the forceps opening 45, the eye-piece optical system 46, the eye-piece portion 47, the retaining portion 48, the universal cord 49, the connector 50, and the magnetic resonance signal output portion 51. As a typical example thereof, the container portion 42 may be formed of resins when iron or the like having a high purity is included in the materials forming the portions other than the container portion 42. The distal end portion 41, however, may include a slight amount of low magnetic permeability metal.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the receiver coil is not limited to a loop-like shape. The material of the coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
According to the thirteenth embodiment having the above structure, a tube is inserted into a body cavity while observing the inside of the body cavity by means of an eye-piece optical system 46, and thus, the container portion 42 is precisely positioned at a target portion.
After insertion of the tube, a magnetic resonance signal received by a magnetic resonance signal receiver coil not shown but included in the container portion 42 is transmitted to a magnetic resonance cross-section video apparatus not shown through the insertion portion 43, the retaining portion 48, a signal transmit means not shown but included in the universal cord 49, and the magnetic resonance signal output portion 51 connected to the transmit means. The signal is supplied from the output portion 51 to a magnetic resonance video apparatus, and accordingly, an MR-image is obtained. This MR-image may be displayed on one single monitor screen together with an endoscope optical image.
Therefore, according to this embodiment, another advantage is obtained in that an endoscope image can be observed so that observation and a diagnosis can be performed using both of the MR- and endoscope images, in addition to the same advantages as obtained in the first embodiment.
Further, both of an MR-image and an endoscope image may be displayed on one single monitor, or these images may otherwise be displayed in a different manner.
Fourteenth Embodiment
A magnetic resonance imaging device 40 according to the fourteenth embodiment has a structure similar to the thirteenth embodiment shown in FIGS. 5A and 5B. In this fourteenth embodiment, the materials forming the container portion 42 and the distal end portion 41 have magnetic permeabilities lower than those of the materials forming the insertion portion 43, the forceps opening 45, the eye-piece optical system 46, the eye-piece portion 47, the retaining portion 48, the universal cord 49, the connector 50, and the magnetic resonance signal output portion 51. Further, the material forming the insertion portion 43 has a magnetic permeability lower than those of the materials forming the other portions than the container portion and the distal end portion 41. Specifically, the portions are divided into three regions whose magnetic permeabilities are different from each other. As a typical example of this, the insertion portion 43, the container portion 42, and the distal end portion 41 are made of resins, when iron having a high purity is included in the materials forming the other portions than the insertion portion 43, the container portion 42, and the distal end portion 41. The insertion portion 43, however, may include a small amount of low magnetic permeability metal.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may use a pick-up element to perform electric treatments. The shape of the receiver coil is not limited to a loop-like shape. The material of the receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The fourteenth embodiment having the above structure operates in the same manner as in the thirteenth embodiment explained above. Further, according to the this embodiment, another advantage is obtained in that not only the distal end portion 41 and the container portion 42 but also the insertion portion 43 is not attracted by a magnet of a magnetic resonance video apparatus, so that safety can be ensured for both of an operator and a patient during use of the device, in addition to the same advantages as obtained in the thirteenth embodiment.
Fifteenth Embodiment
This fifteenth embodiment has a structure similar to the thirteenth embodiment shown in FIGS. 5A and 5B. In a device 40 for a magnetic resonance imaging apparatus, the materials forming the distal end portion 41 and the container portion 42 have magnetic permeabilities lower than those of the distal end portion 41, the insertion portion 43, the forceps opening 45, the eyepiece optical system 46, the eye-piece portion 47, the retaining portion 48, the universal cord 49, the connector 50, and the magnetic resonance signal output portion 51. In addition, the material forming the insertion portion 43 has a magnetic permeability lower than those of the materials forming the other portions than the distal end portion 41 and the container portion 42.
Further, the materials forming the portions other than the distal end portion 41, including the container portion 42, and the insertion portion 43 have magnetic permeabilities equal to or lower than metal materials forming an operating portion of a conventional endoscope.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may use a pick-up element to perform electric treatments. The material of the signal receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The fifteenth embodiment having the above structure operates in the same manner as in the thirteenth embodiment described above. Further, according to this embodiment, another advantage is obtained in that the entire tube of the device is not attracted by a magnet so that safety can always be ensured for an operator, an assistant operator, and a patient, including the operating time in which the device is used, in addition to the advantages obtained in the fourteenth embodiment.
Sixteenth Embodiment
FIG. 6 shows an outer appearance of the sixteenth embodiment of the present invention. A tube of the device 60 for a magnetic resonance imaging apparatus according to this sixteenth embodiment comprises a distal end portion 61 having an optical system not shown, a coil container portion 62 having the same structure as the fourth embodiment explained above, and a hard insertion portion 63 having the same structure as the fourth embodiment. An eye-piece portion 65 having an eye-piece optical system 64 as well as a retaining portion 66 are provided at a bottom end of the insertion portion 63. Further, the retaining portion 66 is connected with a universal cord 67 in which an illumination optical system and a magnetic resonance signal transmission system are inserted. An extended top end of the universal cord 67 is provided with a connector 68 for receiving illumination light from a light source not shown, and a magnetic resonance signal output portion 69 for outputting a magnetic resonance signal received by the container portion 62 to a magnetic imaging apparatus coupled with the device but not shown in the figure.
In this structure, the material forming the container portion 62 has a permeability lower than those of the materials forming the distal end portion 61, the insertion portion 63, the eye-piece optical system 64, the eye-piece portion 65, the retaining portion 66, the universal cord 67, the connector 68, and the magnetic resonance signal output portion 69.
As a typical example thereof, the container portion 62 may be formed of resins when iron or the like having a high purity is included in the materials forming the portions other than the container portion 62.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may uses a pick-up element to perform electric treatments. The shape of the receiver coil is not limited to a loop-like shape. The material of the coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
According to the sixteenth embodiment having the above structure, a tube is inserted into a body, particularly into a ventricle, a pleural cavity, a joint, or a peritoneal cavity, while observing the inside of the body by means of the eye-piece optical system 64, and the container portion is precisely positioned at a target portion when a tube is thus inserted into a body, a hard tube such as a a tracheal tube not shown which can be inserted into the body from outside may be subsidiarily used.
After insertion of the tube, a magnetic resonance signal received by a magnetic resonance signal receiver coil not shown but included in the container portion 62 is transmitted to a magnetic resonance imaging apparatus not shown through the insertion portion 63, the retaining portion 66, a signal transmit means not shown but included in the universal cord 67, and the magnetic resonance signal output portion connected to the transmit means. The signal is supplied from the output portion to a magnetic resonance video apparatus, and accordingly, an MR-image is obtained. This MR-image may be displayed on one single screen together with an endoscope optical image.
According to this embodiment, another advantage is obtained in that a tube can be easily inserted into a body, particularly into a ventricle, a pleural cavity, a joint, or a peritoneal cavity, and the receiver coil container portion can be precisely positioned at a target portion, in addition to the advantages obtained in the fourth embodiment. Further, an endoscope image can be observed so that observation and a diagnosis can be performed using both of the MR- and endoscope images.
Further, both of an MR-image and an endoscope image may be displayed on one single monitor, or these images may otherwise be displayed in a different manner.
Seventeenth Embodiment
The seventeenth embodiment has a structure similar to the sixteenth embodiment shown in FIG. 6. In a tube used in the device of this embodiment, however, the materials forming the distal end portion 61 and the container portion 62 have magnetic permeabilities lower than those of the materials forming the insertion portion 63, the eye-piece optical system 64, the eye-piece portion 65, the retaining portion 66, the universal cord 67, the connector 68, and the magnetic resonance signal output portion 69.
Further, the material forming the insertion portion 63 has a magnetic permeability lower than those of the materials forming the other portions including the container portion 62 and the distal end portion 61. As a typical example of this, the insertion portion 63, the container portion 62, and the distal end portion 61 are made of resins, when iron having a high purity is included in the materials forming the other portions than the insertion portion 63, the container portion 62, and the distal end portion 61. The insertion portion 63, however, may include a small amount of low magnetic permeability metal.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may use a pick-up element to perform electric treatments. The shape of the receiver coil is not limited to a loop-like shape. The material of the receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The seventeenth embodiment having the above structure operates in the same manner as in the sixteenth embodiment explained above. Therefore, according to the this embodiment, another advantage is obtained in that not only the distal end portion 61 and the container portion 62 but also the insertion portion 63 is not attracted by a magnet of a magnetic resonance video apparatus, so that safety can be ensured for both of an operator and a patient during use of the device, in addition to the same advantages as obtained in the sixteenth embodiment.
Eighteenth Embodiment
The eighteenth embodiment has a structure similar to the sixteenth embodiment shown in FIG. 6. In a tube of the eighteenth embodiment according to the present invention, however, the materials forming the distal end portion 61 and the container portion 62 have magnetic permeabilities lower than those of the materials forming the insertion portion 63, the eye-piece optical system 64, the eye-piece portion 65, the retaining portion 66, the universal cord 67, the connector 68, and the magnetic resonance signal output portion 69. The material forming the insertion portion 63 has a magnetic permeability lower than those of the materials forming the portions other than the container portion 62 and the distal end portion 61.
Further, the materials forming the other portions than the insertion portion 63, the container portion 62, and the distal end portion 61 have permeabilities equal to or lower than that of metal material forming an operating portion of a conventional endoscope.
In addition, the shapes are hot limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may use a pick-up element to perform-electric treatments. The shape of the receiver coil is not limited to a loop-like shape. The material of the receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The eighteenth embodiment having the above structure operates in the same manner as in the sixteenth embodiment explained above. However, according to the this embodiment, another advantage is obtained in that the entire tube of the device is not attracted by a magnet, so that safety can always be ensured for an operator, an assistant operator, and a patient, including the time while the device is used, in addition to the same advantages as obtained in the seventeenth embodiment.
Nineteenth Embodiment
FIGS. 7A and 7B schematically show the structure of a device for a magnetic resonance imaging apparatus according to the nineteenth embodiment of the present invention. In this embodiment, a tube of the device comprises a distal end portion 71 having an opening for an optical system and a conduit system both not shown, a magnetic resonance signal receiver coil container portion 72 having the same structure as the in the first embodiment, a bend portion 73 having the same structure as in the seventh embodiment, an insertion portion 74 provided with wires 40a for bending the device and with guide members 41a for protecting the wires 40a in a flexible tube having the same structure as in the thirteenth embodiment, a forceps opening 81, an eye-piece portion 83 having an eye-piece optical system 82, a conduit system control means 84 for controlling the conduit system, a retaining portion 85, a bending control means 86 for controlling bending of the device, and a bending maintain means 87 for maintaining an arbitrary bending state.
An operating portion 89 of the device is constituted by the forceps opening 81, the eye-piece optical system 82, the eye-piece portion 83, the conduit system control means 84, the retaining portion 85, the bending control means 86, and the bending maintain means 87. This operating portion is provided with a universal cord 91 in which an illumination optical system and a magnetic resonance signal transmission system are inserted, a connector 92 for receiving illumination light from a light source not shown, an air-feed hole 93 for receiving air from a light source device not shown, electric contact points 94 for supplying the eye-piece portion 83 with an electric power source, a connector receiver 95 for releasing a high-frequency leakage current, an intake hole 96, a water feed hole 97, and a magnetic resonance signal output portion 98 for outputting a magnetic resonance signal received by the container portion 72 to a magnetic resonance imaging apparatus coupled with the device. The device according to this embodiment is constituted by the components as cited above.
In this structure, the material forming the container portion 72 has a permeability lower than those of the materials forming the portions other than the container portion. As a typical example thereof, the container portion 72 may be formed of resins when iron or the like having a high purity is included in the materials forming the portions other than the container portion 72.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the receiver coil is not limited to a loop-like shape. The material of the coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
According to the nineteenth embodiment having the above structure, a tube is inserted into a body cavity while observing the inside of the body cavity by means of an eye-piece optical system and while adjusting the bend portion 73 by means of the bending control means 86 and the bending maintain means 87, and thus, the container portion 72 is precisely positioned at a target portion.
After insertion of the tube, a magnetic resonance signal received by a magnetic resonance signal receiver coil not shown but included in the container portion 42 is transmitted to a magnetic resonance video apparatus not shown through the insertion portion 74, the operating portion 89, a signal transmit means not shown but included in the universal cord 91, and the magnetic resonance signal output portion 98 connected to the transmit means. Accordingly, an MR-image is obtained. This MR-image may be displayed on one single monitor screen together with an endoscope optical image.
According to this embodiment, another advantage is obtained in that a tube can be more easily inserted into a body cavity with much less burdens to a patient, and the receiver coil container portion can be precisely positioned at a target portion.
Twentieth Embodiment
A device for a magnetic resonance imaging apparatus according to this twentieth embodiment has the same structure as the nineteenth embodiment shown in FIGS. 7A and 7B. In a tube of the device of the twentieth embodiment, however, the materials forming the distal end portion 71, the container portion 72, and the bend portion 73 have magnetic permeabilities lower than those of the materials forming the portions other than these portions 71, 72, and 73.
Further, the material forming the insertion portion 74 has a magnetic permeability lower than those of the materials forming the portions other than the distal end portion 71, the container portion 72, and the bend portion 73. As a typical example thereof, the insertion portion 74, the bend portion 73, the container portion 72, and the distal end portion 71 may be formed of resins when iron or the like having a high purity is included in the materials forming the portions other than the insertion portion 74, the bend portion 73, the container portion 72, and the distal end portion 71. The insertion portion 74 may include a small amount of low magnetic permeability metal.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The shape of the signal receiver coil is not limited to a loop-like shape. The material of the signal receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The twentieth embodiment having the above structure operates in the same manner as in the nineteenth embodiment described above. According to this embodiment, an advantage is obtained in that not only the distal end portion 71, the container portion 72, and the bend portion 73 but also the insertion portion 74 is not attracted by a magnet of a magnetic resonance video apparatus, so that safety can be ensured for both of an operator and a patient, in addition to the advantages obtained in the nineteenth embodiment.
Twenty-first Embodiment
The twenty-first embodiment has the same structure as the nineteenth embodiment shown in FIGS. 7A and 7B. In this embodiment, the materials forming the distal end portion 71, the container portion 72, and the bend portion 73 have magnetic permeabilities lower than those of the materials forming the other portions than these portions 71, 72, and 73, and the material forming the insertion portion 74 has a magnetic permeability lower than those of the materials forming the portions other than the distal end portion 71, the container portion 72, and the bend portion 73 (this corresponds to claim 1).
Further, the materials forming the portions other than the distal end portion 71, the container portion 72, the bend portion 73, and the insertion portion 74 have permeabilities equal to or lower than that of metal material forming an operating portion of a conventional endoscope.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may use a pick-up element to perform electric treatments. The shape of the signal receiver coil is not limited to a loop-like shape. The material of the signal receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The twenty-first embodiment having the above structure operates in the same manner as in the twentieth embodiment described above. According to this embodiment, an advantage is obtained in that the entire tube of the device is not attracted by a magnet resonance video apparatus of a magnetic so that safety can be ensured for an operator, an assistant operator, and a patient, including the time when the device is used, in addition to the same advantages as obtained in the twentieth embodiment.
Twenty-second Embodiment
FIGS. 8A and 8B schematically show the structure of a device according to the twenty-second embodiment of the present invention, wherein FIG. 8A shows a perspective view of the entire outer appearance of the device, and FIG. 8B is a perspective view showing a partial cross-section of an insertion portion which will be described later.
In this embodiment, a tube of the device comprises a distal end portion 71 having an opening for an optical system and a conduit system both not shown, a receiver coil container portion 72 having the same structure as in the fourth embodiment, a bend portion 73 having the same structure as in the seventh embodiment, wires 40a for bending the device as shown in FIG. 8B, protection guide members 41a for receiving and guiding the wires 40a, an insertion portion 74 including of a hard tube which can be inserted into a body, an insertion hole 101, an eye-piece portion 103 having an eye-piece optical system 102, a retaining portion 104, a bending control means 105 for controlling bending of the device, and a bending maintain means 106 for maintaining an arbitrary bending state. An operating portion 107 is constituted by the insertion hole 101, the eye-piece portion 103, the retaining portion 104, the bending control means 105, and the bending maintain means 106. Further, this device comprises a universal cord 111 in which an illumination optical system and a magnetic resonance signal transmission system are inserted, and the universal cord 111 has an extended top end provided with a connector 112 for receiving illumination light from a light source not shown, and a magnetic resonance signal output portion 113 for outputting a magnetic resonance signal received by the container portion 72 to a magnetic resonance imaging apparatus coupled with the device.
In this structure, the material forming the container portion 72 has a permeability lower than those of the materials forming the portions other than the container portion. As a typical example thereof, the container portion 72 may be formed of resins when iron or the like having a high purity is included in the materials forming the portions other than the container portion 72.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may use a pick-up element to perform electric treatments. The shape of the receiver coil is not limited to a loop-like shape. The material of the coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
According to the twenty-second embodiment having the above structure, the tube of the device is inserted into a body while observing the inside of the body by means of an eye-piece optical system and while adjusting the bend portion 73 by means of the bending control means 105 and the bending maintain means 106, and thus, the container portion 72 is precisely positioned at a target portion. When the device is inserted into a body, it is possible to subsidiarily use a hard tube not shown, in which the distal end portion 71, the container portion 72, and the insertion portion 74 can be inserted and which can be inserted into the body-from the outside thereof.
After insertion of the tube, a magnetic resonance signal received by a magnetic resonance signal receiver coil not shown but included in the container portion 72 is transmitted to a magnetic resonance video apparatus not shown through the insertion portion 74, the operating portion 107, a signal transmit means not shown but included in the universal cord 111, and the magnetic resonance signal output portion 113 connected to the transmit means. Accordingly, an MR-image is obtained. This MR-image may be displayed on one single monitor screen together with an endoscope optical image.
According to this embodiment, another advantage is obtained in that a tube of the device can be more easily inserted into a body, particularly into a ventricle, a pleural cavity, or a joint and the receiver coil container portion 72 can be precisely positioned at a target portion, in addition to the same advantages as obtained in the sixteenth embodiment.
Twenty-third Embodiment
The twenty-third embodiment has the same structure as the twenty-second embodiment shown in FIG. 8. In a tube of the device of this embodiment, particularly, the materials forming the distal end portion 71, the container portion 72, and the bend portion 73 have magnetic permeabilities lower than those of the materials forming the portions other than these portions 71, 72, and 73.
Further, the material forming the insertion portion 74 has a magnetic permeability lower than those of the materials forming the portions other than the distal end portion 71, the container portion 72, and the bend portion 73. As a typical example thereof, the insertion portion 74, the bend portion 73, the container portion 72, and the distal end portion 71 may be formed of resins when iron or like materials having a high purity is included in the materials forming the portions other than the insertion portion 74, the bend portion 73, the container portion 72, and the distal end portion 71. The insertion portion 74 may include a small amount of low magnetic permeability metal.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may use a pick-up element to perform electric treatments. The shape of the signal receiver coil is not limited to a loop-like shape. The material of the signal receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The twenty-third embodiment having the above structure operates in the same manner as in the twenty-second embodiment described above. According to this embodiment, another advantage is obtained in that not only the distal end portion 71, the container portion 72, and the bend portion 73 but also the insertion portion 74 is not attracted by a magnet of a magnetic resonance imaging apparatus, so that safety can be ensured for both of an operator and a patient during use of the device, in addition to the advantages obtained in the twenty-second embodiment.
Twenty-fourth Embodiment
The twenty-fourth embodiment has the same structure as the twenty-second embodiment shown in FIGS. 8A and 8B. In this embodiment, particularly, the materials forming the distal end portion 71, the container portion 72, and the bend portion 73 of the device have magnetic permeabilities lower than those of the materials forming the portions other than these portions 71, 72, and 73, and the material forming the insertion portion 74 has a magnetic permeability lower than those of the materials forming the portions other than the distal end portion 71, the container portion 72, and the bend portion 73.
Further, the materials forming the portions other than the distal end portion 71, the container portion 72, the bend portion 73, and the insertion portion 74 have permeabilities equal to or lower than that of metal material forming an operating portion of a conventional endoscope.
In addition, the shapes are not limited to those specified above, as long as the requirements also specified above are satisfied. The optical system may use a pick-up element to perform electric treatments. The shape of the signal receiver coil is not limited to a loop-like shape. The material of the signal receiver coil is not limited to copper, as long as it is a low magnetic permeability metal which is electrically conductive.
The twenty-fourth embodiment having the above structure operates in the same manner as in the twentieth embodiment described above. According to this embodiment, another advantage is obtained in that the entire tube of the device is not attracted by a magnet so that safety can always be ensured for an operator, an assistant operator, and a patient, including the time when the device is used, in addition to the same advantages as obtained in the twenty-third embodiment.
Although the magnetic resonance signal receiver coil portion has been explained in the above embodiments, this coil portion may also be used to generate a resonance signal. Otherwise, another coil for generating a resonance signal may be provided in a probe.
In the embodiments of the present invention as has been stated above, an endoscope is cited as the device for a magnetic imaging apparatus. However, the features of the device according to the present invention are not limited to application to an endoscope, but can be applied to various operation treatment devices which are inserted into a body or a body cavity in a similar manner.
For example, the present invention can be applied to such an operation treatment device as will be exemplified by scissors-type forceps including a cutter means such as forceps at its distal end portion, an insertion portion, and a handling side operating portion, or by clamping forceps which has a similar structure except that a clamping means is provided at the distal end portion.
Otherwise, the present invention may be applied to a detection device as well be exemplified by a suction needle which has a tube path internally extending from a distal end portion through an insertion portion to a handling side portion and which sucks and collects organism tissue.
The following twenty-fifth to thirtieth embodiments relate to devices used for surgical operation under use of an endoscope. In recent years, surgical operations under use of an endoscope have been carried out mainly with use of a rigid scope such as a peritoneal cavity scope or the like and forceps. These devices have been applied not only to peritoneal cavities but also to brains, medullas, secondary nasal cavities and the like, which are difficult to view with eyes. In addition to such rigid scope, a soft scope is used depending on positions and usages. If these operations are carried out with use of a magnetic resonance imaging apparatus and an endoscope image and an MR-image are observed together, treatments can be made with much higher safety.
These operation devices need not always include a receiver antenna, but must be made of materials which do not influence MR-images. However, the entire device need not be made of such materials. More specifically, those portions of the device which are brought into contact with tissue and are positioned in the vicinity of a target portion to he treated must be made of material which do not cause disturbances in MR-images, i.e., materials having a extremely small magnetic susceptibility. On the other hand, those portions of the device which are inserted into a body and are positioned outside an area to be picked-up as an MR-image or positioned within a gas (which is not visualized in an MR-image) in a peritoneal cavity may be made of materials under less restricted conditions, and do not cause practical problems. Those portions of the device which are positioned outside a body are, apparently, not within the area picked up as an MR-image, and therefore, these portions may be made of materials which have a magnetic susceptibility higher than the other portions, as long as these portions are not attracted by a magnet.
Twenty-fifth Embodiment
The device of this embodiment relates to a rigid scope 200 shown in FIG. 9, and this rigid scope 200 includes an insertion portion 201 and a retaining portion 202. The insertion portion 201 consists of a top end member 203 and an intermediate member 204, and a coating or a tube made of PTFE of a fluorine-based resin, ceramics or the like is coated so as to surround the insertion portion.
An objective lens system 206, a relay lens system 207, and a light guide cable 208 are provided in the insertion portion 201. The objective lens system 209 and a pick-up element 210 such as a solid-state pick-up element are arranged in the retaining portion 202, and the light guide cable 208 and a cable 211 including a cord of the pick-up element 210 are arranged at a rear end of the retaining portion 202.
Further, the magnetic susceptibility of the material forming the top end member 203 is greater than that of the material forming the intermediate member 204, which is greater than the material forming the retaining portion 202. For example, the top end member 203 is made of copper or aluminum, the intermediate member 204 is made of titanium or chatcopyrite, and the retaining portion 202 is made of austenite-based stainless steel or the like.
In general, when an operation is made with use of a laparoscope, the top end member 203 is positioned in the vicinity of a portion to be treated, the intermediate member 204 is positioned in an area of the peritoneal cavity which does not influence an MR-image, and the retaining portion 202 is positioned outside the body. Therefore, the structure as stated above does not influence MR-images. Further, there is a case where the rigid scope 200 is substantially inserted into tissue of an organism. In this case, it is desirable that the intermediate member 204 is made of the same material as that forming the top end member 203.
In this embodiment, since the pick-up element 210 is provided in the retaining portion 202, influences of noise onto an MR-image is reduced and a countermeasure for shielding can be easily provided in comparison with a structure in which a pick-up element is provided at a distal end portion.
In place of the relay lens system, a refractive index gradient type lens or an image conduit made of hardened glass fibers may be used.
Twenty-sixth Embodiment
The device of this embodiment relates to an injection needle 220 shown in FIG. 10. In this injection needle 220, the magnetic susceptibility of the material forming a needle 221 is greater than that of the material forming an insertion portion 222, which is greater than the material forming a connector 223.
Twenty-seventh Embodiment
The device of this embodiment relates to forceps shown in FIG. 11, and the material forming a jaw member 240 of the forceps has the smallest magnetic susceptibility. Materials forming a link member 241, a rod member 242, and a pipe member 243 have magnetic susceptibilities greater than that of the jaw member 240.
A member 245 of a handle portion 244 is made of a material having a magnetic susceptibility much greater than the materials of the members 241, 242, and 243. For example, the jaw member 241 is made of copper alloy coated with ceramics, titanium, or titanium alloy. The members other than the handle portion 244 may be formed of the material which has the smallest magnetic susceptibility. In this case, it is possible to obtain the same advantages as obtained in the twenty-sixth embodiment.
Twenty-eighth Embodiment
The device of this embodiment relates to a pressure emission element 260 shown in FIG. 12. This pressure emission element has a top end member 261 formed into a loop-like shape, and the top end member 261 projects from and returns into the top end of an insertion portion 264 as a knobs 263 is moved forwardly and backwardly in relation to a handle 262. The top end member 261 is prepared by coating a strip made of copper or titanium with PTFE or the like, and this member has the smallest magnetic permeability among components constituting the pressure emission element 260.
Twenty-ninth Embodiment
The device of this embodiment relates to a treatment electrode 270 shown in FIG. 13. The electrode 270 is made of a material having a low magnetic susceptibility such as copper coated with titanium nitride (TIN), an insertion portion 271 is made of a material having a magnetic susceptibility greater than the material forming an electrode portion 272, such as stainless steel, chalcopyrite, titanium, or the like, and coated with an insulating coating made of PTFE or the like. A retaining portion 273 is made of a plastic material in view of electric safety.
Thirtieth Embodiment
The device of this embodiment relates to a rigid scope 280 shown in FIG. 15, and this rigid scope 280 has a tissue pressure emission member, e.g., a balloon 281 which is expanded by feeding a gas through a mouth ring 282. This device has the same structure as shown in FIG. 6, except that a receiver antenna is not provided.
Since a space can be formed between the device and organism tissue by an expansion member 281, an MR-image of desired tissue is not influenced even when a material which slightly causes influences onto an MR-image is used in portions close to the top end of the device. This embodiment can be applied to a soft scope.
Thirty-first Embodiment
The device of this embodiment is a modification of the thirty embodiment. As shown in FIG. 14, a plurality of copper lines 283 coated with RTFE or the like are provided as a tissue pressure member, such that the copper lines can be expanded.
Although the magnetic resonance signal receiver coil portion may also be used to generate a resonance signal. Otherwise, another coil for generating a resonance signal may be provided in the device.
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 representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | A device for use in combination with a magnetic resonance imaging apparatus which generates a static magnetic field and detects magnetic resonances in a living body is placed in the static magnetic field, includes a distal end portion and another portion having an end connected to the distal end portion. The distal end portion has a magnetic permeability of such a value that diagnosis and treatment are not influenced by magnetic resonance image distortions due to a disturbance in a uniformity of the static magnetic field generated by the apparatus. The device includes other portions which have a magnetic permeability which is higher than that of the distal end portion and have a value so that the other portions are prevented from being attracted to the static magnetic field. The device does not adversely influence magnetic resonance images since the device is not attracted to a magnet of the magnetic resonance imaging apparatus, thereby increasing an accuracy in diagnosis and treatment. | 6 |
BACKGROUND
1. Field of Invention
The present invention relates to oil and gas production. More specifically, the present invention relates to a tool that creates a shockwave in a wellbore to “back-off” threads engaged in a threaded couplings within a tubular string.
2. Description of Prior Art
Typically, tubulars are connected together by threaded couplings to form a string that is suspended and cemented in a wellbore to create a casing for the wellbore. From time to time, the casing string may need to be removed from the wellbore and the threaded couplings are decoupled at surface. In some instances while removing the casing it may become wedged within the wellbore; further complicating string removal, while still downhole, one of the threaded couplings may resist detachment under an applied torque to become immovable. The immovable coupling is sometimes unseated by directing a shockwave at the coupling site to break loose the threaded connection.
A typical prior art tool used to create this shockwave consists of multiple strands of detonator cord wrapped around a shot rod in a rope-like fashion and wrapped with friction tape. Generally this tool employs a detonation cord having HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), which can withstand operating temperatures of 400 degrees Fahrenheit for only about an hour. While a detonating cord having HNS (1,3,5-Trinitro-2-[2-(2,4,6-trinitrophenyl)ethenyl]benzene) can operate at temperatures above those limiting use of HMX detonator cord, HNS detonating cord cannot side detonate and thus is not utilized in the above described prior art tool. Also, operating pressure of typical prior art is limited to 20,000 psi due to the use of exposed (to wellbore fluids) interface between detonator and detonating cord.
SUMMARY OF THE INVENTION
The present disclosure involves a method of unseating a threaded connection that connects sections of wellbore tubing. In an example the method uses a tool that includes a housing, a shaped charged located inside the housing, an HNS detonating cord and an energetic material attached to the steel housing. The tool is placed near the threaded connection, where it is detonated, creating a shockwave that contacts the threaded connection with sufficient force to unseat the threaded connection.
Also disclosed is a method of an operation in a wellbore that includes inserting an amount of reactive material within a string of wellbore tubular segments, where a threaded connection joins upper and lower adjacent tubular segments. A shockwave is generated by initiating the reactive material that unseats the threaded connection by directing the shockwave towards the threaded connection. The upper tubular segment is rotated thereby eliminating the threaded connection and the upper tubular segment is removed from the wellbore. In an example, the reactive material is initiated by a jet from a shaped charge that terminates proximate an outer surface of the reactive material. In one alternative embodiment, the reactive material includes a high explosive, wherein initiating the high explosive causes the high explosive to detonate. Optionally, the reactive material is a low explosive, wherein initiating the low explosive causes the low explosive to deflagrate. In another alternative, the reactive material includes a combustible material, wherein initiating the combustible material causes the combustible material to combust. Alternatively, initiating the reactive material includes using a detonation cord having HNS to detonate a shaped charge thereby forming a jet, and directing the jet at the reactive material. The pressure can be at least about 30,000 pounds per square inch within the string of tubular segments. At least a portion of the HNS detonating cord can be maintained at a temperature of at least about 480° F. and for a time up to about 1 hour.
Also disclosed herein is an embodiment of a back off tool for use in a downhole tubular. In one example the back off tool includes a body selectively suspended in the downhole tubular by attachment to a deployment member. A reactive material is included adjacent the body for generating a shockwave to unseat an immovable threaded connection between adjacent tubular segments. An initiator is provided in selective communication with the deployment member and in selective initiating communication with the reactive material. In one example, the initiator is a shaped charge that forms a jet to initiate a reaction in the reactive material. Alternatively, a detonating cord having HNS can be included with the back off tool. In an example embodiment, the body and the reactive material each include an axis, and the reactive material is disposed adjacent an end of the body and positioned so that the axis of the reactive material is substantially parallel with the axis of the body. Alternatively, the reactive material can be a high explosive.
BRIEF DESCRIPTION OF DRAWINGS
Some of the features and benefits of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a side sectional view of an embodiment of a back-off tool in accordance with the present disclosure.
FIG. 2 is a partial cutaway side view of a back-off operation.
FIG. 3 is a partial cutaway side view of a shockwave striking the threaded coupling.
FIG. 4 is a partial cutaway side view of a wellbore as the upper casing section is removed.
FIG. 5 depicts in a side sectional view an alternate embodiment of a back-off tool in accordance with the present disclosure.
While the invention will be described in connection with the preferred embodiments, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF INVENTION
The method and system of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings in which embodiments are shown. The method and system of the present disclosure may be in many different forms and should not be construed as limited to the illustrated embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey its scope to those skilled in the art. Like numbers refer to like elements throughout.
It is to be further understood that the scope of the present disclosure is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. In the drawings and specification, there have been disclosed illustrative embodiments and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation. Accordingly, the improvements herein described are therefore to be limited only by the scope of the appended claims.
FIG. 1 depicts, in a cross-sectional view, an embodiment of a portion of a back off tool 20 that can be used in high pressure and high temperature applications. In the example of FIG. 1 , the back off tool 20 includes an annular gun tube 22 shown containing a shaped charge 24 and oriented orthogonal to an axis A X of the gun tube 22 . The shaped charge 24 is shown having an open end set within an opening 25 formed through a side wall of the gun tube 22 . In the example of FIG. 1 , the gun tube 22 is enclosed in a tubular housing 26 that, in an example embodiment, may be formed from steel. A detonating cord 28 is further included with the embodiment of the back off tool 20 of FIG. 1 . The detonating cord 28 , which in an example embodiment may be an HNS detonating cord, is shown extending along the gun tube 22 and routed so that its path runs adjacent an end of the shaped charge 24 . A sleeve 30 is shown encasing the outer surface of the tubular housing 26 . The sleeve 30 may be formed from an energetic material that when initiated reacts and generates a shockwave. Materials for the sleeve 30 can include any material capable of generating a shockwave, examples include an oxidizer, a propellant, a high explosive, e.g. HMX, RMX, HNS, a low explosive, a combustible material, and combinations thereof.
The material for the sleeve 30 can detonate, deflagrate, combust, or a combination thereof. In an example, the definition of detonation describes a reaction that can propagate through the material being detonated at the sound speed of the material. In a further example, detonation describes a reaction or decomposition of an explosive that, typically in response to a shock wave or heat, forms a high pressure/temperature wave. Example velocities of the high pressure/temperature wave can range from 1000 m/s to in excess of 9000 m/s. In an example, the definition of deflagration describes a rapid autocombustion of a material, such as an explosive. Generally, explosives that detonate are referred to as high explosives and explosives that deflagrate are referred to as low explosives. In an example, combustion describes an exothermic reaction of a material that can produce an oxide.
In one example of operation, and as provided in FIGS. 2-4 , a detonation wave is initiated in the detonating cord 28 that transfers a shock wave to and detonates the shaped charge 24 . As will be discussed in further detail below, in one example embodiment of the back off tool 20 , a jet (not shown) formed from detonation of the shaped charge 24 penetrates the housing 26 and the sleeve 30 reacting the sleeve 30 , which provides the necessary shockwave for the back-off operation. In an example embodiment, the jet does not extend past the sleeve 30 , or extends slightly past.
Referring now to FIG. 2 , shown in a side sectional view is an embodiment of the back off tool 20 . In the embodiment of FIG. 2 , the back off tool 20 is suspended by a wireline 32 shown being reeled from and controlled by a surface truck 33 . Alternatively, the wireline 32 can be threaded through a wellhead assembly (not shown) disposed on the surface. The back off tool 20 and wireline 32 are inserted within a string of wellbore casing 34 that line a wellbore 35 . The casing string is made up of segments of casing 34 , each segment having threaded ends that threadingly couple together to form a threaded connection 36 . More specifically in the example of FIG. 2 , the back off tool 20 is suspended adjacent a threaded connection 36 that is immovable. For the purposes of discussion herein, and as described above, a threaded connection 36 that is immovable describes a threaded connection 36 that resists decoupling.
In the example embodiment of FIG. 3 shown in side partial sectional view is an example embodiment where the shaped charge 24 in the back off tool 20 has been detonated that in turn initiates detonation of the sleeve 30 . When the sleeve 30 is detonated it creates a shockwave 38 that propagates through the threaded connection 36 , as shown in FIG. 3 . The force of the shockwave 38 can remove stresses in the threaded connection 36 joining upper and lower segments of casing 34 U , 34 L thereby allowing the threaded connection 36 to back-off as torque is applied to the upper segment of casing 34 U . Thus continued application of torque to the upper segment casing 34 U rotates the upper segment of casing 34 U decoupling upper and lower threads 37 U , 37 L to eliminate the threaded connection 36 that couples the upper and lower segments of casing 34 U , 34 L . As shown in side sectional view in FIG. 4 , once decoupled, the upper segment of casing 34 U can be detached from the lower segment of casing 34 L and removed from the wellbore 35 . In an optional embodiment, the back off tool 20 includes more than one sleeve 30 so that a shock wave can be generated at a first depth, the back off tool 20 raised or lowered to a second depth, and another shock wave generated by initiating the more than one sleeve.
An alternate embodiment of a portion of a back off tool 20 A is shown in a side sectional view in FIG. 5 . The back off tool 20 A of FIG. 5 includes a shaped charge 24 A suspended from a length of detonating cord 28 A shown disposed inside a generally cylindrically shaped housing 26 A. Disposed adjacent to a lower end 39 of the housing 26 A is a substantially cylindrically shaped amount of reactive material 40 oriented generally coaxial with the housing 26 A. In an example embodiment, the reactive material 40 includes the same or similar material of the sleeve 30 as described above. The shaped charge 24 A of FIG. 5 is oriented so that when detonated any jet resulting from the shaped charge 24 A is directed towards the lower end 39 and reactive material 40 , rather than a side radial wall as illustrated in the example of FIG. 1 . In the example embodiment of FIG. 5 , an axis A H of the housing 26 A is shown to be substantially coaxial with an A EM of the reactive material 40 . Embodiments exist as well where the axes A H , A EM are substantially parallel. Optionally, the reactive material 40 may be encased in a jacket 42 for protecting the reactive material 40 during the trip downhole. Operation of the back off tool 20 A of FIG. 5 is similar to the operation described above; that is, the back off tool 20 A is inserted into a tubular string and the reactive material 40 is reacted, such as by detonating the shaped charge 24 A. An ensuing shock wave, not shown, transfers energy to an immovable threaded connection so that the connection can be decoupled.
The present invention described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment of the invention has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. For example, the back off tool 20 and its alternate embodiments can be disposed in other downhole tubulars, such as production tubing strings, caissons, risers, and the like. These and other similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present invention disclosed herein and the scope of the appended claims. | A method for unseating a threaded connection of wellbore tubing within the wellbore. The method utilizes a back-off tool which consists of a tubular metal housing, a shaped charge and HNS detonating cord within the housing, and an explosive material attached to the housing. The back-off tool is detonated near the threaded connection, creating a shockwave that strikes the threaded connection with sufficient force to unseat the connection. | 4 |
BACKGROUND OF THE INVENTION
A. Field of the Invention
The present invention is directed to a non-skid surface structure that can be used as a floor, or a mat adapted for placement on garage floors, and includes, preferably features that render it relatively water resistant, oil resistant and non-slip.
B. Description of the Prior Art
Various non-skid surface structures are known, as described, for example, in U.S. Pat. Nos. 4,662,972, 5,475,951, 5,500,267 and 5,763,070. However, none of these structures provide the combination of features yielding the usefulness, flexibility, durability, ease of manufacture, and practicality of the present invention.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the present invention to provide a non-slip, water resistant, oil resistant surface structure that can be used as a floor or as a mat for placement on garage floors and other flat surfaces where the presence of water and/or oil may create a slippery surface.
It is a further object of the present invention to provide a method of making a non-slip, water resistant and oil resistant surface structure that can be used as a floor or as a mat for placement on garage floors and other floor areas.
With reference to the above-described object, the present invention provides a surface structure that can be used as a floor or as a mat having a skid surface which is adapted for use on floors, stairs and other surfaces, as well as a method of for preparing such a mat.
The method of manufacture of the present surface structure includes coating a base material, preferably wood, with a thermosetting epoxy resin, and then placing a cloth which has been dipped in the epoxy resin material on the base material and allowing both to dry until the coating hardens. The coated, hardened base material is then coated with a third coating of the thermosetting epoxy resin, which third coat contains abrasive materials such as walnut shells or other granular materials and then allowing the third coating to dry and harden. The coated base, cloth dipped, granular coated substrate is then fastened to a conventional rubber-bottomed mat with an appropriate adhesive, such as “Gorilla Glue” and/or conventional fasteners. The size, depth, width, length and thickness of the surface structure may vary.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of the method of manufacturing the surface structure of the present invention.
FIG. 2 is a top view of a first, preferred embodiment of the surface structure of the present invention.
FIG. 3 is a is a top view of a second, preferred embodiment of the surface structure of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a schematic diagram of the method of manufacture 20 of the surface structure of the present invention will be described. First, a substrate or sheet 22 is selected. Preferably the substrate is a wooden board or other durable, flat material. The substrate functions as a main supporting member and upon which and over which one or more layers of coating material are applied. Next, a first coating is applied at step 24 . The 1 st coating is a mixture of SIKAGARD 62 HI BILD Part A and Part B thermosetting epoxy resin materials. The preferred coating for the mat of the present invention is an epoxy resin sold as SIKAGARD 62 HI BILD, which product includes a Part A epoxy compound, and a Part B amine curing agent, manufactured by the SIKA Corporation of Lindhurst, N.J. 07071. A copy of the SIKA Corporation product information sheet on its SIKAGARD 62 HI BILD product is incorporated by reference herein, and a copy is submitted herewith.
The Part A and Part B liquids are mixed in accordance with the instructions provided by the manufacturer. Once the SIKAGARD 62HI BILD mixture is prepared, the board is coated with the mixture. Then a section of a cloth of sufficient size to cover the board is then dipped in the SIKAGARD 62 HI BILD-Part A and Part B mixture. The mixture laden cloth is then laid on the board and permitted to dry, so that the coating hardens. The cloth is preferably a bedsheet-like material used to cover joints and nicks on the base material; it gives the base material a smoother finish and makes the epoxy resin bond stronger and harder to the coated base material, as shown in at 26 in FIG. 1 .
Next, a third coating is applied in step 28 . In this third coating, a third mixture of the SIKAGARD 62 HI BILD Part A and Part B is prepared, in accordance with the instructions from the manufacturer. Then, to this third mixture a quantity of crushed walnut shells or other granular material are added. In addition to crushed walnut shells, “SIKAGARD 62 granules” are preferred. SIKAGARD 62 granules are also commercially available from Sika Corporation. The granular material is mixed, preferably at a concentration of approximately ½ pound of granular material per gallon of the epoxy/amine mixture. The amount of granular material added may vary but must be at least enough to provide the function of yielding a non-slip surface in the finished product, but not so much granular material that the epoxy coating is unable to provide a coating that will adhere to the substrate. The mixture containing the granular material is then applied to the coated base material and the coating is allowed to dry and harden, thus forming a base material having two coatings, one of which contains SIKAGARD 62 HI BILD Part A and Part B, second one of which contains cloth dipped SIKAGARD 62 HI BILD Part A and Part B and a third one of which contains granular material, as shown at 30 .
Once the three times coated board is dried, it is fastened to a conventional rubber-bottom structure or mat with an adhesive and/or conventional fasteners. Preferably, an adhesive commercially available and known as “Gorilla Glue” is used, as illustrated at 32 in FIG. 1 . Once the coated substrate is attached to the rubber-bottomed mat, the non-skid, water resistant, oil resistant mat of the present invention results, as shown at 34 . Other adhesives may be used in the present invention, so long as they function to adhere the coated substrate to the rubber-bottom structure or mat.
With reference to FIG. 2, a first preferred embodiment of the finished surface structure 34 of the present invention is illustrated. In a first embodiment 36 , the mat has an overall size of 4 feet by 6 feet, with a two-inch wide, 8{fraction (1/16)} of an inch thick border as illustrated in FIG. 2 . The center of the structure is approximately 3 feet, 1 inch across from the inside peripheries of the border. The depth of the structure below the top surface of the borders is {fraction (4/16)} of an inch. The size, depth, width, length and thickness of the structure and its various components can vary, according to the particular application chosen. Such variances are within the skill of the art in this field.
With reference to FIG. 3, a second preferred embodiment 38 will be described. The mat 38 is a surface structure having a rubber center strip 40 and an overall size of approximately 15 feet, 11 inches by 17 feet, 5 inches. In the embodiment 38 , a one inch wide, {fraction (8/16)} of an inch thick rubber center strip 40 separates two sections of the structure 42 and 44 , each of which has a rubber outer strip 46 and 48 , respectively. These outer strips 46 , 48 are each 2 inches wide and {fraction (8/16)} of an inch thick, with a depth of {fraction (4/16)} of an inch. Preferably the surface structure 38 is {fraction (8/16)} of an inch thick and the sections 42 and 44 may be interlocked, in a conventional tongue-in-groove fashion, as is well-known.
As may be appreciated, one of the advantages of the present inventions is that a non-skid surface substrate may be easily manufactured to conform to the dimensions of commercially available rubber mats, and to thereby provide a non-skid function for such surface structures when used in locations where the presence of oil, water and other such liquids might cause a slippery surface.
As may be appreciated, and as believed to be within the capability of those skilled in this field, the mats can be made to have different shapes, colors and structures that provide for interlocking sections to each other and in various configurations. Also, although rubber is the preferred bottom material, other elastomeric materials may be used, so long as they are durable in the chosen environment and are able to be fastened to the created substrate.
The SIKAGARD 62 HI BILD, Part A is an epoxy resin, specifically epichlorohydrin/bisphenol. The SIKAGARD 62 HI BILD Part B amine-curing agent includes 2, 4, 6-tri(dimethylaminomethyl) phenol in a concentration of 5 ppm and is available in various colors. The composition also includes a proprietary blend of aliphatic and cyclic amines, coated precipitated calcium carbonate, amorphous silica and titanium dioxide. In the green colored product, chromium III oxide (2:3) is included in a concentration of 0.5 mg/m 3 . The coated, precipitated calcium carbonate is in the range of 10 mg/m 3 -5 mg/m 3 . The amorphous silica is provided in a concentration of 20 mppcf to 10 mg/m 3 , and the titanium dioxide is in a concentration of 10 mg/m 3 to 15 mg/m 3 , except in the red colors.
It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations as they are outlined within the description above and within the claims appended hereto. While the preferred embodiments and application of the invention have been described, it is apparent to those skilled in the art that the objects and features of the present invention are only limited as set forth in the claims appended hereto. | A non-slip, water resistant, oil resistant surface structure for use where water and/or oil are likely to create a slippery surface, including a rubber-bottom mat upon which a thrice coated, non-slip surfaced substrate is fastened, the coating on the substrate including crushed walnuts, or the equivalent, to provide for a non-slip surface and the coating comprising a thermosetting epoxy resin material with an amine hardener. | 4 |
BACKGROUND OF THE INVENTION
[0001] Various processes are known for preparing sorbic acid. A particularly economical process starts from the polymeric polyester reaction product which is prepared by reacting crotonaldehyde with ketene in an inert solvent in the presence of a fatty acid salt of a divalent and/or trivalent metal of subgroups II to VIII of the Periodic Table of the Elements as catalyst (DE-A-10 42 573).
[0002] Sorbic acid can be produced in various ways from this polyester.
[0003] An industrially important process consists of thermal catalytic cleavage of the polyester which comprises cleaving the polyester in the presence of an inert diluent which boils at atmospheric pressure above 150° C., preferably above 180° C. (DE-A-10 59 899) and 0.5% to 50% of a secondary or tertiary amine boiling at atmospheric pressure above 100° C., preferably above 150° C., as catalyst at temperatures of 160° C. to 220° C., simultaneously distilling off the sorbic acid and the diluent (DE-A-12 82 645). Particularly suitable solvents are the aliphatic carboxylic acids of appropriate boiling point specified in DE-A-10 59 899.
[0004] When this process is carried out industrially, the cleavage is carried out in a continuous distillation apparatus. The sorbic acid polyester dissolved in the diluent is charged into the distillation vessel where the amine-catalyzed cleavage of the sorbic acid polyester to give sorbic acid takes place. The sorbic acid formed is distilled off together with the diluent via a rectification column at 160-200° C. and 20-50 hPa with reflux. Rectification is necessary in order to prevent the transfer of amine into the distillate and to achieve the appropriate purity.
[0005] The sorbic acid is then crystallized out of the distillate and separated off from the diluent. The diluent is recirculated.
[0006] In parallel to the desired cleavage of the sorbic acid polyester to give sorbic acid, a decarboxylation reaction of the sorbic acid polyester takes place to give carbon dioxide and pentadiene, and thus decreases the yield. This reaction can largely be suppressed by increasing the amine content in the bottom-phase of the cleavage. Thus, for example, an approximately 4% higher yield of sorbic acid is obtained when the amine concentration in the bottom-phase of the cleavage is increased from 10% to 40%.
[0007] Since in the thermal cleavage of sorbic acid polyester in the distillation vessel, in addition to sorbic acid, polymers are also formed which do not distill under these conditions and lead to an increase in the bottom phase, these continuously formed polymers must constantly be discharged as residue. Since the catalyst amine is mixed with the polymers, catalyst amine is also unavoidably co-discharged from the bottom, so that to maintain the amine concentration in the bottom-phase of the cleavage, fresh amine must constantly be added.
[0008] To quadruple the concentration of the catalyst amine in the bottom phase, in order to achieve the increase in yield in cleavage of the sorbic acid polyester, the amine feed must also be approximately quadrupled. Since this amine must be discharged again together with the polymer from the bottom, however, this also means quadrupling the amount of amine as residue.
[0009] It was therefore an object to develop a process in which the catalyst amine is recovered from the residue and thus can be reused for repeated use as catalyst for cleavage of sorbic acid polyester.
BRIEF DESCRIPTIONS OF THE INVENTION
[0010] The invention therefore relates to a process for preparing sorbic acid by thermal cleavage of the polyester prepared from crotonaldehyde and ketene in which, from the inevitably produced residue, the amine used as catalyst is recovered and can thus be reused. This first provides the possibility of increasing the amine concentration in the bottom-phase of the cleavage to achieve a higher yield of sorbic acid without amine being lost. Secondly, as a result, the use of fresh amine can be reduced. In addition, this is accompanied by a reduction in the total amount of residue.
DETAILED DESCRIPTION OF THE INVENTION
[0011] Surprisingly, it has been found that by distilling the residue at 190 to 220° C., preferably 205 to 215° C., and at a pressure of 5 to 15 hPa, preferably 7 to 9 hPa, the catalyst amine can be selectively separated off from the other bottom-phase constituents.
[0012] Advantageously, the process can be carried out in a thin-film evaporator. Particularly good results are obtained when a tertiary amine is used as catalyst, in particular a trialkylamine having two C 1 -C 3 -alkyl groups, in particular methyl groups, and an alkyl chain having 14 to 20 carbon atoms, in particular 15 to 17, very particularly preferably 16 carbon atoms.
[0013] Suitable diluents to carry out the cleavage of the sorbic acid polyester are aliphatic, alicyclic, aromatic hydrocarbons, their chlorine, bromine and nitro derivatives, and also ethers and silicone oils whose boiling point at atmospheric pressure is above 150° C., preferably above 180° C. However, ketones, esters, carboxylic acids and alcohols having the appropriate boiling range can also be used as diluents, although in general the results are not quite as good, since they apparently in part react with the reaction mixture. It is expedient to use those diluents or solvents which are liquid at ambient temperatures, boil at atmospheric pressure below 300° C., preferably below 270° C., and form azeotropic mixtures with sorbic acid, so that they at the same time act as entrainers, such as petroleum fractions, dodecane, tetradecane, 5-methyldodecane, dodecene, dicyclohexylmethane, p-di-tert-butylbenzene, 1-methyinaphthalene, 2-methylnaphthalene, 1-ethylnaphthalene, tetrahydro-naphthalene, diphenylnaphthalene; halogenated aliphatic, cycloaliphatic or aromatic hydrocarbons such as dichlorododecane, 1,5-dibromopentane, benzotrichloride, o- and m-dibromobenzene; nitro compounds such as nitrobenzene, 2-nitrotoluene; nitrites such as benzyl cyanide; carbonyl compounds such as acetophenone or the heterocyclic 2-acetylthiophene; heterocyclic compounds such as chromane, thiophene; ethers such as resorcinol dimethyl ether, diphenyl ether, safrole, isosafrole; acids such as enanthric acid, α-ethylcaproic acid, caprylic acid, capric acid; or esters such as ethyl benzoate, methyl phenylacetate and methyl salicylate.
[0014] The examples below illustrate the invention.
[0015] The starting material is a polyester-containing reaction product which was obtained in a similar manner to DE-B-10 42 573, example 1. In this method 420 g of ketene are introduced at a temperature between 25° C. and 35° C. into a stirred mixture of 800 g of crotonaldehyde, 1200 ml of toluene and 14.2 g of zinc isovalerate. The excess crotonaldehyde and the toluene are removed in vacuo. The residue obtained is 1150 g of polyester in the form of a high-viscosity brown liquid. In addition to the zinc content of 3000 ppm, this reaction product still contains fractions which cannot be converted into hexadienoic acids, such as diketene polymers and crotonaldehyde resins.
[0016] The proportion convertible into hexadienoic acids was determined by basic saponification of a solution of 60 g of sorbic acid polyester in 120 g of toluene using 33 g of potassium hydroxide in 260 g of water at room temperature. This produces in the aqueous phase potassium sorbate and the potassium salt of 3-hydroxy-4-hexenoic acid, from which hexadienoic acid can be produced by acidification. The proportion of the polyester which can be converted into hexadienoic acids can be determined by quantitative determination of the two reaction products by means of HPLC.
[0017] Under these mild conditions, the polyester content can be determined much more accurately than as described in DE-A-12 82 645. Thus the proportion of the crude polyester which is convertible into hexadienoic acids is 89 to 90% and not, as assumed in DE-A-12 82 645, only 80%. The yields achieved in DE-A-12 82 645 must therefore be corrected, see example 1 (comparative example).
EXAMPLE 1
Comparative Example
[0018] The apparatus consists of a 1 l 3-neck round-bottomed flask (reaction flask) having an attached distillation column. The distillation column, of a filling height of 600 mm and an internal diameter of 40 mm, is packed with glass Raschig rings 6 mm in diameter. The distillation column bears a column top cooled to 70° C. with a reflux splitter. The reflux splitter firstly recycles condensed distillate to the column, and secondly passes it for collection in a graduated heatable receiver (500 ml) and a 6 l round-bottomed flask. The entire apparatus is operated under vacuum, and an oil pump with an upstream dry ice cold trap generates the vacuum.
[0019] This apparatus is operated semibatchwise, and to achieve statistically meaningful results, a plurality of experiments are carried out reusing the filtrate and bottom-phase liquid produced in the respective preliminary experiment.
[0020] In the first experiment, 260 g of a mixture consisting of 12% dimethylhexa-decylamine and 88% Arkopal® (=nonylphenol polyglycol ether as residue liquefier) are placed in the reaction flask.
[0021] The apparatus is evacuated to about 30 hPa and the reaction flask is heated with the oil bath (bath temperature approximately 220° C.). When the temperature in the reaction flask reaches 180° C., the feed mixture is metered (417 g/h) into the reaction flask at a reflux ratio of 1.
[0022] The feed mixture for the reaction flask consists of 350 g of polyester (see above), 2128 g of ethylhexanoic acid, 12 g of dimethylhexadecylamine and 10 g of Arkopal® (=nonylphenol polyglycol ether as residue liquefier) (total amount 2500 g).
[0023] After the feed mixture has been metered in, pure 2-ethylhexanoic acid is run through the apparatus without polyester and without reflux (834 g) for 2 hours and then redistilled for 5 min. The distillate situated in the receiver is homogenized by heating to 50-55° C. and then cooled in the course of 3 hours to 20° C. with stirring (500 rpm). After this temperature has been reached, the mixture is kept for a further 15 min at 20° C. and then the crystallized crude sorbic acid is filtered off with suction and the pure content determined by gas chromatography.
[0024] In this experiment the bottom phase in the reaction flask increases by 62 g (starting from 260 g). This increase in residue consists of 12 g of dimethylhexadecylamine, 10 g of Arkopal, 2 g of sorbic acid and 2-ethylhexanoic acid and 38 g of sorbic acid polymer and is discharged from the system.
[0025] In each further experiment, after separating off the crude sorbic acid, the filtrate is used in the feed mixture, instead of the pure 2-ethylhexanoic acid, together with 350 g of polyester, 12 g of dimethylhexadecylamine and 10 g of Arkopal.
[0026] Then, 260 g of the bottom phase from the respective preliminary experiment is placed in the reaction flask, which bottom phase has a mean dimethylhexa-decylamine concentration of 12%.
[0027] After the experiment has been carried out a number of times, a mean sorbic acid yield of 74% is obtained. Based on the pure polyester, that is solely taking into account the proportion of 90% which can be cleaved to form hexadienoic acids, a yield of 82.2% is thus calculated.
EXAMPLE 2
[0028] The sorbic acid polyester cleavage procedure is carried out as in example 1 (comparative example). In the first experiment, 260 g of a mixture consisting of 40% dimethylhexadecylamine and 60% Arkopal® (=nonylphenol polyglycol ether as residue liquefier) are placed in the reaction flask.
[0029] The feed mixture for the reaction flask consists of 350 g of polyester (from example 1), 2128 g of 2-ethylhexanoic acid, 48 g of dimethylhexadecylamine and 14 g of Arkopal (total amount 2540 g).
[0030] The bottom phase in this reaction increases by 104 g. This increase in residue consists of 48 g of dimethylhexadecylamine, 14 g of Arkopal, 4 g of sorbic acid and diluent and 38 g of sorbic acid polymer and must be discharged from the system before the next experimental procedure.
[0031] The filtrate, after separating off the crude sorbic acid, is reused in the feed mixture in the following experiment, instead of the 2-ethylhexanoic acid, together with 350 g of polyester, 48 g of dimethylhexadecylamine and 12 g of Arkopal.
[0032] Then, 260 g of the bottom phase from the respective prior experiment is placed in the reaction flask, which bottom phase has a mean dimethylhexadecylamine concentration of 40%.
[0033] After the experiment has been carried out a number of times, a mean sorbic acid yield of 79.9% is obtained. Based on the pure polyester, that is to say only taking into account the proportion of 90% which can be cleaved to form hexadienoic acids, a yield of 88.7% is thus calculated.
EXAMPLE 3
[0034] The sorbic acid polyester cleavage procedure is performed as in example 2.
[0035] As in example 2 the bottom phase in this reaction increases by 104 g. This increase in residue consists of 48 g of dimethylhexadecylamine, 14 g of Arkopal, 4 g of sorbic acid and 2-ethylhexanoic acid and 38 g of sorbic acid polymer and must be discharged from the system before the next experimental procedure.
[0036] In a thin-film evaporator, this discharged bottom-phase residue is distilled at 210° C./8 hPa. For a thin-film evaporator heating area of 16 cm 2 , a throughput of 450 g/h is possible. The rotor equipped with movable scraper blades has a peripheral velocity of 3 m/s. 205 g/h of distillate and 245 g/h of residue discharge. The starting amount of 104 g produces 47 g of distillate and 57 g of residue.
[0037] The sorbic acid polymers and the liquefier Arkopal, in addition to small amounts of dimethylhexadecylamine, are present in the thin-film evaporator effluent. The majority of the ejected amine (43 g) and 4 g of sorbic acid and 2-ethylhexanoic acid are present in the distillate.
[0038] This distillate is supplemented with 5 g of fresh dimethylhexadecylamine to 48 g of total amine and reused in a similar manner to example 2 in the next cleavage experiment together with the diluent from the crude sorbic acid separation, 350 g of polyester and 12 g of Arkopal.
[0039] After the experiment had been carried out a number of times with recirculation of the amine a mean sorbic acid yield of 79.9% is obtained. Based on the pure polyester, that is to say only taking into account the proportion of 90% which is cleavable to form hexadienoic acids, a yield of 88.7% is calculated.
[0040] Yields and amine usage of the respective experiments are compared in summary form in the table below:
Example 1 Example 2 Example 3 Amine content in the bottom phase 12% 40% 40% Amine recycling no no yes Yield 82.2% 88.7% 88.7% Increase in residue during the 62 g 104 g 104 g reaction “Fresh” amine feed 12 g 48 g 5 g Amine feed from amine recirculation 43 g Residue ejected from the system 62 g 104 g 57 g | The invention relates to a process for preparing sorbic acid by cleaving the sorbic acid polyester prepared from crotonaldehyde and ketene, the sorbic acid polyester being distilled and the cleavage being catalyzed by an amine, which comprises separating off the amine from the distillation residue by distillation under reduced pressure and at a temperature which is higher than the temperature of the polyester distillation and recovering it. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a central processing unit (CPU) for an electronic data processing system and, more particularly to a CPU which provides programmable optional autoloading of memory pointer registers without requiring that the autoloading condition of each memory pointer register be specified by the operation code (op-code) of an instruction.
Autoloading is the process by which certain registers for storing memory location addresses are automatically loaded with an address carried by an instruction. The address which is automatically loaded is normally associated with a memory location containing an operand. Autoloading enables certain registers to be loaded implicitly without requiring separate instructions.
The op-code of an instruction is a group of binary digits (bits) that define a processor operation such as ADD, SUBTRACT, COMPLEMENT, etc. The set of processor operations formulated for a CPU depends on the processing it is intended to carry out. The total number of distinct operations which can be performed by the CPU determines its set of processor operations.
The number of bits which form the op-code (op-code field) is a function of the number of operations in the set. At least N bits are necessary to define 2 N or less distinct operations. The CPU designer assigns a different bit combination (i.e., op-code) to each operation. The controller section of the CPU detects the bit combination at the proper time in a sequence and produces proper command signals to required destinations in the CPU to execute the specified operation.
In addition to specifying a processor operation, an instruction will normally also carry other information such as means for determining the address(es) of memory locations where operand(s) to be used in the processor operations are stored. In many instruction formats, the number of bits required for the operand address(es) (address field) occupy most of the bit positions available in the instruction leaving only a limited number of bits to be allocated for the op-code field. When a CPU designer finds the bits allocated to the op-code field insufficient for a given set of processor operations he has, heretofore, had the choice of either accepting a smaller set of processor operations or lengthening the instruction.
Prior art techniques for permitting program control of autoloading have been to use a designated bit in the op-code or the memory address mode code to specify the autoloading condition of each memory pointer register. Where both the op-code and the memory address mode code lengths are insufficient to define new codes, additional bits must be added. For example, if two memory pointer registers are to have the optional autoloading feature, two bits in the op-code would have to be reserved to specify the autoloading condition of the two registers. However, adding bits in the op-code or the memory address mode code has the effect of making the instructions longer.
Long instructions are disadvantageous in small data processing systems where the memory capacity for storing instructions is limited. In addition, small systems have limited word sizes as well (as small as 4 bits) in some systems where the CPU is in the form of a microprocessor), and a long instruction has the added disadvantage of requiring many memory references for retrieval and, thus, of slowing down CPU operation. However, from the standpoint of versatility, programming convenience, and operating efficiency, it is desirable to have optional programmable autoloading. Therefore, a problem in designing a CPU for small data processing systems is that of being able to define optional programmable autoloading while minimizing instruction length.
SUMMARY OF THE INVENTION
The present invention provides a CPU of a data processing system designed for executing a program of stored instructions through a sequence of instruction cycles, the CPU being adapted to be coupled to memory means for storing instructions and data, the memory means having multiple memory locations each associated with a distinct memory location address, the CPU receiving during each instruction cycle an instruction from the memory means, each instruction comprising an op-code part and an address part, the CPU including a memory pointer register for storing an address of a memory location containing data, characterized in that the CPU is adapted to receive from the memory means stored data comprising operand words and op-code extension words, the CPU being further adapted to receive instructions having address parts which comprise an address associated with a memory location containing an operand word, and the CPU further includes an op-code extension register for storing a selected op-code extension word, the op-code extension register having a designated bit position corresponding to the memory pointer register, the contents of the op-code extension register being changed only when the CPU executes an instruction for transferring a newly selected op-code extension word to the op-code extension register, address transfer means responsive to the contents of the designated bit position for transferring before end of an instruction cycle an address contained in an instruction received during the instruction cycle if the designated bit position contains a first binary state.
Thus autoloading of the memory pointer registers can be specified by software without requiring that each instruction corresponding to a processor operation in which autoloading may be used carry information concerning whether or not the autoloading option is enabled. The op-code field in such instructions which need only define the generic operation need not be increased inasmuch as the op-code extension word in the op-code extension register modifies the generic operation according to whether or not autoloading has been selected.
Accordingly, it is an object of the invention to provide a CPU architecture which provides programmable optional autoloading of memory pointer registers without including information concerning autoloading in the op-code of an instruction.
It is another object of this invention to provide a CPU architecture which improves the versatility and performance of a small data processing system having a small word size and limited instruction storage capacity.
It is still a further object of this invention to provide a CPU architecture for reducing the number of memory references required to fetch an instruction in a data processing system having a small word size.
Yet another object of the instant invention is to provide a CPU architecture for low cost, high performance microprocessors.
The above and other objects of the invention are achieved in several illustrative embodiments described hereinafter. However, it should be appreciated that there are possible useful embodiments which are designed to achieve less than all of the preceding objects while still remaining consistent with the principles of the invention. The novel features of the invention, both as to structure and method of operation, together with further objects and advantages thereof will be better understood from the following description considered in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are solely for the purpose of illustration and description and are not intended to define limits of the invention.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagram illustrating a CPU known in the prior art.
FIG. 2 is a flow chart useful for illustrating the processor sequence during an instruction cycle.
FIG. 3 is a state diagram illustrating the sequence of steps followed by the CPU of FIG. 1 in executing an ALU operation.
FIG. 4 is a block diagram illustrating a CPU in which the width of operands for ALU operations is placed under program control.
FIG. 5 is a logic diagram of the Carry-In Administration Circuit, used in the CPU of FIG. 4.
FIG. 6 is a logic diagram of the Carry-out Multiplexer Circuit used in the CPU of FIG. 4.
FIG. 7 is a logic diagram of the Carry-Out Register Circuit used in the CPU of FIG. 4.
FIG. 8 is a logic diagram of the Rotate/Shift Right Administration Circuit used in the CPU of FIG. 4.
FIG. 9 is a logic diagram of the ALU Function Inhibit Circuit used in the CPU of FIG. 4.
FIG. 10 is a block diagram illustrating a CPU in which the optional features of variable operand width, autoloading and autoincrementing of memory pointer registers are placed under program control in accordance with the present invention.
FIG. 11 depicts the Op-code Extension Register used in the CPU of FIG. 10.
FIG. 12 is a state diagram illustrating the sequence of steps followed by the CPU of FIG. 10 in executing an ALU operation and the operation of the variable operand width and autoincrementing features.
FIG. 13 is a state diagram illustrating the sequence of steps followed by the CPU of FIG. 10 in address formation and the operation of the autoloading feature.
DETAILED DESCRIPTION
Referring now to FIG. 1 there is shown a block diagram representative of a simple CPU, 100, known in the prior art and of a type which is found in small data processing systems such as minicomputers and microprocessor based systems. Only those parts of the CPU which are essential to the explanation to follow have been included in FIG. 1. The configuration of FIG. 1 uses a single Instruction Register (IR), 101, which stores the current instruction being executed. A program of instructions to be executed by the CPU is stored in a Read-Only-Memory (ROM), 102, in the form of binary words hereafter referred to as instruction words. In this example, each instruction word contains eight bits. The CPU retrieves an integral number of instruction words from the ROM to form a complete instruction. Each instruction is composed of an op-code specifying an operation which the CPU is designed to perform and an address code specifying the memory location where an operand or operands to be used for the specified operation are stored. In the CPU of FIG. 1, the operands are stored in a Random Access Read-Write Memory (RAM), 103, also in the form of binary words hereafter referred to as operand words. Although in this example the instructions are stored in a ROM and the operands in a RAM it is also possible to use the ROM for operand storage and the RAM for instruction storage.
In this example, each operand word contains eight bits. An operand is formed with one operand word retrieved from the RAM. The IR holds eight bits of an instruction, six of which are reserved for the op-code, the remaining two being reserved for the part of the address code specifying the addressing mode. Four addressing modes are available in the CPU of FIG. 1, namely the direct mode, two indirect modes, and the immediate data mode. The length of an instruction will vary depending on the addressing mode used. A discussion of these addressing modes which are well known to one skilled in the art of CPU design, can be found in a book entitled Computer Logic Design by M. M. Mano, published by Prentice-Hall, Inc., Englewood Cliffs, New Jersey, 1972, on pages 343-350, and U.S. Pat. No. 3,292,151.
As an illustrative example, the 6-bit op-code is used to define 48 processor operations represented by the instruction set listed in Table 1.
TABLE I__________________________________________________________________________ CPU Instruction SetInstruction Op-Code__________________________________________________________________________1 ADD 0000002 ADD WITH CARRY 0000013 SUBTRACT 0000104 SUBTRACT WITH CARRY 0000115 AND 0001006 OR 0001017 EXCLUSIVE OR 0001108 MOVE 0001119 COMPARE AND BRANCH IF EQUAL 00100010 COMPARE AND BRANCH IF NOT EQUAL 00100111 COMPARE AND BRANCH IF LESS THAN 00101012 COMPARE AND BRANCH IF GREATER THAN/EQUAL 00101113 TEST AND BRANCH IF ZERO 00110014 TEST AND BRANCH IF NOT ZERO 00110115 DECREMENT, BRANCH IF NOT ZERO 00111016 SET 00111117 CLEAR 01000018 INCREMENT 01000119 DECREMENT 01001020 COMPLEMENT 01001121 ROTATE LEFT 01010022 ROTATE LEFT WITH CARRY 01010123 ROTATE RIGHT 01011024 ROTATE RIGHT WITH CARRY 01011125 SHIFT LEFT 01100026 SHIFT LEFT WITH CARRY 01100127 SHIFT RIGHT 01101028 SHIFT RIGHT WITH CARRY 01101129 SET BIT 01110030 CLEAR BIT 01110131 BRANCH ON BIT SET 01111032 BRANCH ON BIT CLEAR 01111133 EXCHANGE 10000034 TEST WITH MASK AND BRANCH IF ZERO 10000135 TEST WITH MASK AND BRANCH IF NOT ZERO 10001036 BRANCH 10001137 JUMP 10010038 CALL 10010139 RETURN 10011040 RETURN FROM INTERRUPT 10011141 CLEAR FLAG REGISTER 10100042 SET FLAG REGISTER 10100143 PUSH 10101044 POP 10101145 EXCHANGE MEMORY POINTER 10110046 LOAD STACK POINTER 10110147 STORE STACK POINTER 10111048 NO OPERATION 101111__________________________________________________________________________
The Program Counter (PC), 104, normally holds the address of the next word of instruction or constant to be retrieved from the ROM. The PC is a 12-bit register which goes through a step-by-step counting sequence pointing to successive instruction words stored in the ROM, except in response to a program transfer instruction (e.g., instructions 9-15, 31, 32, and 34-40 of Table 1) when a new address is loaded into PC. An 8-bit Data Bus, 105, is used for transferring instructions, addresses, and operands between various locations in the CPU. Addresses for accessing locations in the RAM, 103, are stored in the 12-bit Memory Address Latch (MAL), 106, which receives an address from one of a group of registers in the Memory Pointer (MP), 107. The contents of IR are detected by the Controller, 108, which produces command signals for processor operations and address manipulations specified by the detected contents. The command signals are transmitted to various destinations in the CPU via the control lines, 109.
The arithmetic and logical operations are performed in the Arithmetic Logic Unit (ALU), 110, which can receive either one or two operands at its A and B inputs. An Accumulator (ACC), 113, stores an operand for the ALU and also stores the result of the ALU operation. The ALU is provided with a Carry-In input to receive a carry signal and a Carry-Out output where the carry signal generated by the ALU is made available. The input carry signal is provided by the Carry-In Administration circuit, 111, which selects among the Plus 1 signal in the case of an INCREMENT operation, the Carry signal in the case of ROTATE LEFT WITH CARRY operation, or the most significant bit, AC7, of the Accumulator in the case of a ROTATE LEFT operation. The output carry signal is received by the Carry Register (CR), 112, which indicates an ALU function overflow or underflow. The CR is also loadable, resettable, and participates in the SHIFT and the ROTATE operations.
The ACC which has a master section, ACM, and a slave section, ACS, is also used in this example as a latch for data to be read from or written into the RAM. A special Shift/Rotate Right Circuit (SRR), 114, provides for SHIFT AND ROTATE RIGHT operations involving ACC. The SHIFT AND ROTATE LEFT operation is accomplished by adding the operand to itself and, therefore, requires almost no special circuitry. A Rotate/Shift Right Administration Circuit (RSR), 115, is provided to select either the Carry Output signal or the least significant bit, ACO, of ACC to be loaded into the most significant bit position of ACC for the ROTATE RIGHT WITH CARRY and the ROTATE RIGHT operations respectively.
The execution of each instruction by a CPU occurs in a sequence of basic steps which form the instruction cycle. The sequence of steps is governed by timing signals generated by clock circuitry which is not shown in FIG. 1.
Referring now to FIG. 2 there is shown a flow chart of steps in the instruction cycle. The instruction cycle is divided into two phases: an instruction fetch phase and an execution phase. Reference numerals 201 through 206 indicate the basic stages of each phase. In the instruction fetch phase, an instruction word whose address is in PC is transferred from the ROM to IR. The instruction word as previously mentioned has a 6-bit op-code field and a 2-bit address mode field. The first step in the execution phase where data is involved is the formation of the address or addresses of operands required for the operation. The operands are stored in RAM or in internal registers in the CPU. First, the op-code in IR is decoded by the controller to determine whether the operation is monadic, dyadic or one which does not involve data. A monadic operation is one which requires only one operand and, therefore, only one operand address is formed. The sole operand address formed for a monadic operation is called a destination address because the result of the operation is automatically stored in the memory location previously occupied by the sole operand. A dyadic operation is one which requires two operands and, therefore, two operand addresses are formed. The address of the first operand is called the source address while that of the second operand is called the destination address because the results of the dyadic operation will be automatically stored in the location previously occupied by the second operand. In the CPU of FIG. 1, the destination address is generally ACC.
The address mode bits in IR are also detected by the controller. If direct addressing is indicated, an address is transferred from a location in ROM into MAL. If, however, one of the two indirect addressing modes is indicated, the contents of a specified memory pointer register in MP are transferred to MAL. In the case of the immediate data addressing mode, the operand or operands themselves are carried by the address portion of the instruction and, therefore, no operand addresses are formed.
After the operand address is formed and transferred to MAL, the operand may be fetched from the location in RAM pointed to by MAL. The last step in the execution phase is the performance of the operation specified by the op-code in IR which in this example is an ALU function. Completion of the ALU function terminates the instruction cycle.
Referring now to FIG. 3, a state diagram, 300, for the simplified CPU of FIG. 1 is shown. Reference numerals 301 through 310 indicate the detailed steps in an instruction cycle for executing ALU and data transfer operations. Non-data operations such as BRANCH, CALL, RETURN, etc. are classified as Miscellaneous Instructions and are not shown. The dyadic operation ADD between a first operand stored in a RAM location pointed to by a register in MP and a second operand already stored in ACC can be represented by the state sequence
S1→S2→S4→S6→S9→S10.
Referring to the states represented by the blocks designated by reference numerals 301 through 310 in FIG. 3, in state S1 the contents of the ROM location addressed by the contents of PC is transferred to IR. In state S2 the contents of IR are decoded by the Controller. Assuming in this example that the addressing mode is indirect, in state S4, 304, the contents of a specified register in MP are transferred into MAL. In state S6, 306, the operand stored in the RAM location specified by the address in the MAL is transferred to the ALU, and a particular ALU operation specified by the op-code (i.e., ADD) is performed on the above operand and the contents of ACC, with the result transferred to the master section (ACM) of ACC. In state S9, 309, the contents of ACM may, as required by the instruction, be transferred either to the slave (ACS) of ACC or to a RAM location pointed to by MAL. For the ADD operation the result (the sum) remains in ACC. In state S10, 310, PC is incremented before the beginning of a new instruction cycle.
An example of a Monadic operation, SET ACCUMULATOR, can be represented by the state sequence
S1→S2→S7→S9→S10.
The steps represented by the states S1 and S2 are the same as described above for the dyadic operation. In state S7, 307, the ALU generates an 8-bit word having all "1s" and transfers it into ACM. The steps represented by states S9 and S10 are the same as described above for the dyadic operation.
An example of a data transfer operation, MOVE, of a constant stored in the ROM and carried by the instruction to a register in MP is represented by the state sequence
S1→S2→S3→S5→S10.
The steps represented by states S1 and S2 have already been explained in connection wth the dyadic operation. In state S3, 303, PC is incremented to point to the ROM location where the constant is stored. In state S5, 305, the constant in the ROM location pointed to by PC is transferred to MP. The step represented by state S10 has already been explained in connection with the dyadic operation.
The CPU configuration of FIG. 1 can be modified to include processor operations in addition to those listed in Table 1. For example, as will be described in detail, the ALU section can be altered to accommodate 4-bit operands as well as the normal 8-bit operands with the selection of the operand width under program control. Such a modification would affect the arithmetic, logical and data movement operations represented by instructions 1 through 35 in Table 1. The modification would effectively add thirty-five new operations for 4-bit operand width to those listed in Table 1, raising the total number of operations in the set to eighty-three. Inasmuch as the 6-bit op-code field in the CPU of FIG. 1 permits only sixty-four distinct codes, the op-code field must be extended to accommodate the additional operations. Owing to the fact that the word size of the CPU is 8-bits, to avoid interfacing difficulties, it would be necessary to extend the IR by multiples of 8-bits. Therefore, if each instruction were to carry information concerning the operand width, the instruction length would have to increase by at least eight bits. This would cause a considerable increase in ROM space required for storing a program and would also require one more ROM reference to be added to each instruction cycle. The additional memory storage space increases system cost while the additional ROM references slow down system operating speed.
An alternative means for program selection of the operand width is provided by using an op-code extension register. It may be recognized that in most programs, when a particular operand width is selected, many operations may be executed before it becomes necessary to change the operand width. Thus the portion of the op-code field which specifies the operand width remains constant over many instruction cycles while the portion of the op-code field which specifies the operations listed in Table 1 (generic operations) ordinarily changes with each new instruction cycle. Therefore, it would be unnecessary to carry in each instruction the infrequently changing portion of the op-code, which may instead be stored in a special hardware register. For present purposes this special hardware register will be called the op-code extension register (OER). Use of the OER for storing the portion of the op-code which specifies the operand width means that the op-code field in each instruction need only specify the generic operations (e.g., ADD, SUBTRACT, COMPLEMENT, etc.), for which six bits are sufficient. Therefore, by using the OER concept, it becomes unnecessary to increase the instruction length.
In accordance with the above disclosed concept, the OER may also specify other optional features in addition to variable operand width. Some of these other features such as autoloading and autoincrementing of memory pointer registers, and the assignment of address registers, will also be described in detail in this specification.
When there are several optional features to be specified by the OER, there must be a sufficient number of bit positions in the OER to specify all distinct combinations of optional features. A group of bits to be stored by the OER is hereafter referred to as an op-code extension word. The contents of OER are changed only when necessary by means of special instructions (added to the list of Table 1) for transferring to OER a new op-code extension word from memory, and for changing a particular bit in OER. Each op-code extension word corresponds to a distinct combination of special features to be used in the program. Thus, by using the OER concept for program selection of optional features, ROM space is conserved and additional ROM references in each instruction cycle are avoided.
VARIABLE OPERAND WIDTH
Referring now to FIG. 4, there is shown a block diagram representative of a CPU, 400, basically similar to that of FIG. 1 but with modification to permit changing of the operand width from 8 bits to 4 bits. These modifications include dividing the ALU, the Accumulator, and the Shift and Rotate Right Circuit into two independent 4-bit sections which will be referred to as the "higher" and "lower" sections. In FIG. 4, the "higher" sections of the ALU (ALUH), Accumulator (ACCH), and the Shift and Rotate Right Circuit (SRRH), are indicated by reference numerals 410, 416, and 418 respectively. The "lower" sections of the ALU (ALUL), the Accumulator (ACCL), and the Shift Right and Rotate (SRRL) are indicated by reference numerals 411, 417, and 419, respectively. In each case the "higher" and "lower" sections are connected such that when the operand width is 8-bits, the "higher" section operates on the most significant 4-bits of the operand word while the "lower" section operates on the least significant 4-bits of the 8-bit operand word. When the operand width is 4-bits, the "higher" sections of each divided part are rendered inoperative as if the current instruction were NO OPERATION, while the "lower" sections operate on the least significant 4 bits of an operand word.
The Carry-In Adminstration Circuit (CIA), 412, normally provides a "0" to the Carry-In input of ALUL, 411. When the current instruction is INCREMENT, or DECREMENT, the CIA output is a "1". The CIA output is the state of the Carry Register, 413, when the current instruction is ADD WITH CARRY, SUBTRACT WITH CARRY, or ROTATE LEFT WITH CARRY. For the ROTATE LEFT instruction, the CIA output is the most significant bit (AC7) of ACCH in the case of an 8-bit operand and is the most significant bit (AC3) of ACCL in the case of a 4-bit operand. An example of a logical implementation of the CIA is shown in FIG. 5.
The Carry-Out Multiplexer Circuit, (COMX), 414, provides the Carry-Bit input to the Carry Register, 413. The COMX output is either the Carry-Out output of ALUH in the case of an 8-bit operand or the Carry-Out output of ALUL in the case of a 4-bit operand. An example of a logical implementation of the Carry-Out Multiplexer is shown in FIG. 6.
The Carry Register (CR), 413, is a flip-flop which can be set from several sources depending upon the current instruction. The operative inputs of CR for various instructions are listed below:
______________________________________Instruction Operative CR Input______________________________________(ALU Operation) WITH CARRY CB from COMXLOAD CR Data BusCLEAR CR "0"SHIFT RIGHT WITH CARRY "0"ROTATE RIGHT WITH CARRY AC0.______________________________________
An example of a logic implementation of the carry register is shown in FIG. 7.
The Rotate/Shift Right Administration Circuit (RSR), 420, provides the most significant bit for ACCH and/or ACCL in SHIFT AND ROTATE RIGHT operations. In the case of 8-bit operand width, RSR provides the state of the least significant bit (AC0) of ACCL to the most significant bit position (AC7) of ACCH via the OT8 output. In addition RSR provides the state of the least significant bit (AC4) of ACCH to the most significant bit position (AC3) of ACCL via the OT4 output. In the case of 4-bit operand width, RSR provides the state of the least significant bit (AC0) of ACCL to the most significant bit position (AC3) of ACCL via the OT4 output. The inputs and operative outputs of RSR for various instructions are listed below:
______________________________________Instruction Inputs Operative Outputs______________________________________Shift Right (8-bit) 0,AC4 OT8,OT4, -Shift Right (4-bit) 0 OT4Rotate Right (8-bit) AC0,AC4 OT8,OT4Rotate Right (4-bit) AC0 OT4Right Shift/RotateWith Carry (8-bit) carry,AC4 OT8,OT4Right Shift/Rotatewith carry (4-bit) carry OT4.______________________________________
A logical implementation of the Rotate/Shift Right Administrative Circuit is shown in FIG. 8.
The ALU Function Inhibit Circuit (ALUFI), 415, is used to disable ALUH when the operand width is 4-bits. When the operand width is 8-bits, the ALU function control lines, 422, from the controller, 408, govern the selection of ALU functions for both ALUH and ALUL. However, when the operand width is 4-bits, ALUFI applies a control signal to ALUH which corresponds to the NO OPERATION instruction, and ALUH allows operands to pass through unchanged. An example of a logical implementation of the ALU Function Inhibit Circuit is shown in FIG. 9.
When 4-bit operand width is selected for the CPU of FIG. 4, only the least significant 4-bits of the operand word are operated on while the most significant 4-bits are unused. In order to make use of the most significant 4-bits of the operand word and thereby make full use of the RAM storage space for operands it is necessary to provide means to interchange the most significant and least significant 4-bits of the operand word. Such an interchange can be achieved in several ways.
One way to achieve an effective interchange of the most and least significant 4-bits in an operand word is to interchange under the control of a bit position in the OER, the "higher" and "lower" sections of the ALU. For example, if a designated bit position of the OER for controlling the ALU interchange contains a "0" during 4-bit operation, ALFI would inhibit ALUH while ALUL is allowed to operate on the least significant 4-bits of the operand word. However, if the designated bit position contains a "1" during 4-bit operation, ALFI would inhibit ALUL while ALUH is allowed to operate on only the most significant 4-bits of the operand word.
The most and least significant 4-bits of an operand word can be interchanged directly by introducing a ROTATE 4 instruction to the list in Table 1. The CPU of FIG. 4 upon receiving such an instruction transfers an operand word specified by the instruction from RAM to the divided accumulator where initially the most significant 4-bits of the operand word reside in ACCH and the least significant 4-bits reside in ACLL. The operand word is then rotated in the divided accumulator until the previous most significant 4-bits reside in the ACCL and the previous least significant 4-bits reside in ACCH. The "rotated" operand word in the divided accumulator can either be immediately used in an ALU operation or be transferred back to RAM.
Programmable selection of the operand width is by means of the op-code extension register (OER), 421, which in this example need only contain one bit position. When the binary state of that bit is a "1", the operand width for ALU and data movement operations is 4-bits, otherwise the operand width is 8-bits. A LOAD OER instruction is added to the list in Table 1, and the ROM contains two constants, a "1", and a "0", as op-code extension words. Although only one bit is needed to specify the operand width, OER may contain additional bit positions for selecting other optional features as discussed above.
The above-described CPU configuration for implementing variable operand width under program control by using an OER and a divided ALU is specifically claimed in a copending application Ser. No. 974,426 filed concurrently with the instant application.
An alternative CPU configuration for implementing variable operand width as well as other optional features is shown in FIG. 10. Although the CPU architecture of FIG. 10 is basically different from that of FIG. 4, the same op-code extension register concept is used to select the optional features. Referring now to FIG. 10, the Instruction Register, 1001, the ROM, 1002, the RAM, 1003, the Data Bus, 1004, and the Controller, 1005, all serve the same function as their corresponding parts in the CPU of FIG. 4 except the word size of the ROM and RAM, and the widths of the Data Bus and the Instruction Register are all 4-bits instead of 8-bits. The Address Latch (AL), 1006, is a 12-bit master-slave latch for storing the current address of an intruction or of an operand. The 12-bit address arithmetic unit (AAU), 1007, increments or decrements the current address in AL. The Internal Register Memory (IRM), 1008, is a group of registers which include a Program Counter (PC), 1009, two Memory Pointer Registers B0, 1010, and B1, 1011, and a Stack Pointer, 1012. The Temporary Register Memory (TRM), 1013, contains two temporary registers T0, 1014, and T1, 1015, used for intermediate address calculations during the address formation stage. The four address modes available in the CPU of FIG. 4 are also available in the CPU of FIG. 10.
The Data-Address Bus Multiplexer (DAMUX), 1016, controls the transfer of data in 4-bit words from ROM and RAM to the 12-bit registers in IRM and TRM via the 4-bit Data Bus. The DAMUX multiplexes the 4-bits from the Data Bus onto one of three 4-bit sections (designated higher, middle and lower sections) of the Address Arithmetic Bus, 1026. The three sections of the Address Arithmetic Bus are coupled respectively to the higher, middle, and lower 4-bit sections of the 12-bit registers in IRM and TRM. A 12-bit address bus, 1027 transfers addresses from the AL to the AAU, RAM, and ROM.
The 4-bit Arithmetic and Logic Unit (ALU) is used to perform all arithmetic and logical functions. The operands for the ALU are stored in 4-bit temporary data registers TA, 1018, and TB, 1019.
Unlike the CPU of FIG. 4, the CPU of FIG. 10 does not have an addressable accumulator. Instead, the RAM locations pointed to by the Memory Pointer Registers, 1010 and 1011, are allowed to be used as accumulators. This permits the CPU to have as many accumulators as RAM space permits.
The basic operand width of the ALU in the CPU of FIG. 10 is 4-bits; however, its configuration is such that ALU operations can be performed on operands whose widths are integral multiples of the basic width (specifically, 4, 8, 12, and 16-bits). For operands having widths which are multiples of the basic width, the ALU operates on 4-bit segments of the operand beginning with the least significant segment and repeating the ALU operation on the other segments according to their order of significance. A 4-bit segment is commonly referred to as a nibble. The number of repetitions of an ALU operation required for a given operand width is equal to the number of nibbles in the operand.
In the example of FIG. 10, OER has 6 bit positions which are assigned according to FIG. 11. Referring to FIG. 11 a 2-bit field comprising bits b0, 1101, and b1, 1102, specify the four optional operand widths of 4 bits, 8 bits, 12 bits, and 16 bits. The other 4 bit positions of OER are used to specify other special features to be described later in this specification. The coding of bits b0 and b1 and the number of repetitions needed to complete an ALU operation for each state are listed below:
______________________________________b1, b0 operand width ALU repetitions______________________________________00 16-bits 401 4-bits 110 8-bits 211 12-bits 3______________________________________
Referring again to FIG. 10, the number of repetitions of an ALU operation specified by the contents of OER is controlled by the 2-bit Counter, 1021, and the Comparator, 1022, which compares the state of the counter with that of b0-b1. When the state of the counter and that of b0-b1 match, repetition of the ALU operation ceases.
The details of an ALU operation in the CPU of FIG. 10 can be better understood when considered with the State Diagram, 1200, shown in FIG. 12. Referring to FIG. 12, the Instruction Fetch States, 1201, and the Address Formation States, 1202, have already been discussed in connection with FIG. 2. After address formation, the source address for a dyadic operation is stored in temporary register T0. When the operation specified by the current instruction as either monadic or dyadic, the destination address is in temporary register T1. It is to be noted that in the CPU of FIG. 10 a destination address is always required for a dyadic operation, unlike the CPU of FIG. 4 where the accumulator is generally the implied destination for dyadic operations.
In state ALU1, 1203, the contents of T0 (source address) are transferred to the master (ALM) of the Address Latch (1023 in FIG. 10). If the current instruction specifies a monadic operation, the next state is ALU5, 1207; otherwise the next state is ALU2, 1204. During the transition from ALU1 to ALU2, the contents of ALM are transferred to the slave (ALS) of the Address Latch (1024 in FIG. 10), and in state ALU2 the operand stored in the RAM location pointed to by ALS is transferred to temporary data register TB. In state ALU3, 1205, the address in ALS is incremented and transferred to both T0 and ALM, and if another optional feature, autoincrementing, yet to be described, is enabled, the incremented address is also transferred to pointer register B0. If the current instruction specifies immediate data addressing for the second operand of the dyadic operation (i.e., the second operand itself is carried in the address field of the current instruction) the next state is ALU4, 1206. In ALU4 the contents of ALS are tranferred to PC, restoring the ROM address for the next data constant or instruction. For the other addressing modes, the next state is ALU5, 1207, where the destination address stored in T1 is transferred to ALM an the 2-bit Counter is incremented, the Counter having been cleared at the beginning of the instruction cycle. During the transition from state ALU5 to state ALU6 the contents of ALM are transferred to ALS. In state ALU6, 1208, the contents of the RAM location pointed to by ALS are transferred to temporary data register TA. The next state is ALU7, 1209, where ALS is incremented and its contents tranferred to T1 and to B1 if the autoincrementing feature is enabled. The ALU operation specified by the current instruction is performed on two operands provided by TA and TB in the case of a dyadic operation or on a single operand provided by TA in the case of a monadic operation. The next state is ALU8, 1210, where the result of the ALU operation (ALU OUT) is stored in the RAM location pointed to by ALS. The state of the Counter is then compared with the state of b0-b1 in OER. If the Comparator output is true, the ALU operation is completed; but if the Comparator output is false, the CPU returns to state ALU1 and the ALU operation is repeated.
The above described CPU configuration for implementing variable operand width under program control using an OER and an ALU designed to operate repetitively on one nibble of the operand at a time is specifically claimed in copending application Ser. No. 974,425 filed concurrently with the instant application.
AUTOLOADING OF POINTER REGISTERS
Another optional feature of the CPU in FIG. 10 which can be selected under program control using the OER is autoloading of the pointer registers B0 and B1. This feature is only available for the direct addressing mode where the full operand address is carried in the address code of the instruction. When autoloading is enabled, the operand addresses supplied by the current instruction are automatically stored in specified pointer registers at the completion of the instruction cycle. Autoloading of B0 and B1 is controlled by the state of bit positions AL0 (1105 of FIG. 11) and AL1 (1106 of FIG. 11) in OER respectively, a "1" state enabling the autoloading feature.
Autoloading is performed during the address formation stage of the execution phase. A state diagram of the address formation stage for the CPU of FIG. 10 is shown in FIG. 13. An example of address formation is now explained with reference to FIG. 13.
During the instruction fetch phase represented by the block with reference numeral 1301, an instruction word containing an op-code and an address mode code is transferred from ROM to IR. The CPU then goes to the first address formation state AF1, 1302. The path followed by the CPU through the address formation steps depends on the addressing mode specified by the address mode code in IR and on whether the operation specified by the op-code in IR is monadic or dyadic. A D-type flip-flop (DFF), 1025, in the CPU of FIG. 10 keeps track of whether the address being formed for a dyadic operation is a source or destination address. Prior to the formation of the source address of a dyadic operation, DFF is clear (DFF=0), but prior to the formation of the sole operand address of a monadic operation or the destination address of a dyadic operation, DFF is set (DFF=1). If the direct addressing mode is specified for the source address, the most significant (upper) 4-bits of T0, are set to all "1s", and, similarly, if the direct addressing mode is specified for the destination address, the most significant 4-bits of T1 are set to all "1s".
The CPU then proceeds to state AF2, 1303. If the specified addressing mode is for indirect addressing, the contents of B0 are transferred to T1 if DFF is set, or the contents of B0 are transferred to T0 and the contents of B1 are transferred to T1 if DFF is clear. The CPU then proceeds directly to state AF6, 1307. If the specified addressing mode is for immediate data, the state of PC is transferred to T0 and the CPU proceeds directly to state AF6.
In state AF2, for the case of direct addressing, the contents of PC are transferred to ALM, the contents of PC being the address of the ROM location containing the first nibble of the operand address. During the transition from state AF2 to state AF3, 1304, the contents of ALM are transferred to ALS. In state AF3, ALS is incremented and its contents transferred to PC. If another nibble from ROM is required to complete the formation of the address the incremented address is ALS is also loaded into ALM. The contents of the ROM location pointed to by ALS are then transferred to the lower four bits of T0 (T0L) if DFF is set, or to the lower four bits of T1 (T1L) if DFF is clear. During the transition from state AF3 to state AF4, 1305, the contents of ALM are transferred to ALS. In state AF4, ALS is again incremented and its contents transferred to PC. The contents of the ROM location pointed to by ALS are transferred to the middle four bits of T0 (T0M) if DFF is set, or to the middle four bits of T1 (T1M) if DFF is clear. It is to be noted that the upper 4 bits of an operand address in the direct addressing mode is "1111".
If the autoloading feature is not enabled for either B0 or B1, then the CPU proceeds from state AF4 directly to state AF6. Otherwise, the next state is AF5, 1306. In state AF5 the contents of T0 are loaded into B0 if DFF is set and autoloading is enabled for B0 (i.e., AL0=1), or the contents of T1 are loaded into B1 if DFF is clear and autoloading is enabled for B1 (i.e., AL1=1).
In state AF6, the completed operand address in T0 is transferred to ALM. If DFF is set in state AF6, address formation is completed and the CPU proceeds to the ALU function represented by the block with reference numeral 1309. If, however, DFF is clear indicating that address formation for a dyadic operation is incomplete, the CPU proceeds first to state AF7 where DFF is set and then to state AF1 and repetition of the address formation steps for the destination address.
AUTOINCREMENTING OF POINTER REGISTERS
Another optional feature of the CPU of FIG. 10 which can be enabled or disabled by means of the OER is the autoincrementing of the Pointer Registers B0 and B1. When this feature is enabled for a specified Memory Pointer Register, the address stored in that register will be automatically advanced (incremented) at the end of each instruction cycle to point to the memory location of the first nibble of the next operand in the case where the operands are stored in consecutive memory locations. Autoincrementing of B0 and B1 is controlled by the state of the OER bit positions AI0 (1103 of FIG. 11) and AI1 (1104 of FIG. 11), respectively. A "1" state enables the autoincrementing feature.
When enabled, autoincrementing of B0 and B1 take place during the ALU function state of the data execution phase as represented by the state diagram of FIG. 12. Referring now to FIG. 12, as explained above in connection with the variable operand width feature, when the CPU is in state ALU3, 1205, a source address stored in ALS pointing to a nibble of a first operand (assuming a dyadic operation) is incremented to point to the next nibble of the same operand, if the ALU operation is to be repeated on the next nibble. If the ALU operation has been completed on all nibbles of the same operand, ALS points to the first nibble of a new first operand. The incremented address is then transferred to T0 and ALM. If autoincrementing of B0 has been enabled, (i.e., AI0=1), the incremented address is also transferred from ALS to B0. In state ALU7, 1209, a destination address contained in ALS pointing to a nibble of the second operand of the dyadic operation, is incremented and transferred to T1. If autoincrementing of B1 has been enabled (i.e., AI1=1), the incremented address is also transferred from ALS to B1. The ALU operation is then performed on the corresponding nibbles of the first and second operands residing respectively in TA and TB. The result of the ALU operation is stored in the memory location previously occupied by the corresponding nibble of the second operand. The ALU operation is repeated, if required, on additional nibbles of the first and second operands. It is to be noted that with autoincrementing enabled for a particular pointer register its contents are incremented with each repetition of the ALU operation such that at the end of the instruction cycle the pointer register is always pointing to the first nibble of the next operand.
The above described CPU configuration for implementing autoincrementing of memory pointer registers under program control using an OER is specifically claimed in a copending application Ser. No. 974,361 filed concurrently with the instant application. | A Central Processing Unit (CPU) provides programmable autoloading of memory pointer registers. The CPU includes an op-code extension register (OER) to store a code specifying the autoloading status of each memory pointer register. Whether or not a particular memory pointer register is loaded at the end of an instruction cycle with an operand address carried by the current instruction depends on the binary state of a particular bit position in the OER corresponding to the particular memory pointer register. The contents of the OER can be changed by means of an instruction for transferring a new code to OER. A CPU architecture having an OER permits software specification of autoloading without significantly increasing the number of op-codes required to define the instruction set. Fewer op-codes generally permit shorter instructions. The advantages provided by shorter instructions are reduced memory overhead for program storage and increased processing efficiency in data processing systems having a small word size. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a pumpdown, retrievable, subsurface, safety valve for use in a well.
2. The Prior Art
Subsurface, safety valves have been used in wells for some time. When vertical access to the well is available, subsurface, safety valves are generally installed and retrieved using wireline techniques. However, particularly on offshore wells where vertical access to the well is not practical, pumpdown equipment has been used to install or retrieve a subsurface, safety valve in the well.
Conventional subsurface safety valves have included a valve member movable between positions opening and closing the tubing bore to fluid flow. The valve member generally is adapted to move to a position opening the bore in response to fluid pressure. Biasing means are often provided to urge the valve member to a position closing the bore. For a surface conrolled, subsurface safety valve the baising means must overcome the force of the hydrostatic head of control fluid utilized to pressurize a pressure chamber. Because the force exerted by the hydrostatic head of fluid increases as the depth of the valve increases, the force exerted by the biasing means must also increase as the depth of the valve increases.
Springs are one common source of the biasing force for the biasing means. If the valves can be installed by wireline techniques, the biasing means can include a plurality of springs or one large spring. However, if the valve must be installed by pumpdown techniques, present safety valves have not been able to utilize a long spring or a plurality of springs to create the large force necessary to overcome a large hydrostatic head of fluid. This is because the valve must be pumped around a loop or short radius curvature before entering the well. A long valve simply connot be pumped through such a loop or curvature. Thus, pumpdown surface-controlled subsurface safety valves have been limited to the use of short springs to create the biasing force. Short springs have been unable to generate a sufficient amount of force to overcome the hydrostatic head of fluid for a valve positioned deep in the well.
Dome pressure chambers have also been used to create the biasing force. (See U.S. Pat. No. 3,860,066 to Pearce, et al). However, dome chambers also present problems. The seals of the dome chamber could fail resulting in a loss of pressure in the dome. This loss of dome pressure could render the valve totally inoperative, or worse yet, fail to close it.
The problems of present pumpdown, surface-controlled, subsurface, safety valves may be summarized as follows: because of the limitations on the valve length and the limited force that may be created by a short spring, if a spring is used as the biasing means the valves may only be used at shallow depths in the tubing. If a dome pressure chamber is utilized to generate the biasing force, possible leakage of pressure from the dome chamber results in less reliability and safety for the valve.
An injection, subsurface safety valve has similar problems. The biasing means must overcome the force of the hydrostatic head of fluid in the tubing. If a spring is used as the source of the biasing force, the pumpdown, subsurface injection safety valves have also been limited to the use of short springs with their inherent weakness. The reduced reliability of a dome pressure chamber also limits its use in a subsurface injection safety valve.
U.S. Pat. Nos. 3,891,032 to Tausch and 3,899,025 to Dinning disclose utilizing a ball joint in a pumpdown kickover tool body to allow the body to move through the curved portions of the pumpdown well tubing.
OBJECTS OF THE INVENTION
It is an object of this invention to provide a pumpdown, subsurface, safety valve which includes a high force generating spring biasing means and which can be pumped through a short radius curvature.
Another object of this invention is to provide a pumpdown, subsurface, safety valve which includes a plurality of springs to bais the valve closed and which can be pumped through a short radius curvature.
Another object of this invention is to provide a spring closing subsurface, safety valve for pumpdown operations for greater safety and reliability that can be pumped around a short radius curvature.
Another object of this invention is to provide a pumpdown safety valve which permits the use of a plurality of springs to increase the force biasing the valve closed and which may be pumped around a short radius curvature.
It is an object of this invention to provide a pumpdown, retrievable, subsurface, surface-controlled, tubing safety valve which includes a high force generating spring biasing means and which can be pumped through a short radius curvature.
Another object of this invention is to provide a pumpdown, retrievable, subsurface, surface-controlled, tubing safety valve which includes a plurality of springs to bias the valve closed and which can be pumped through a short radius curvature.
Another object of this invention is to provide a spring closing, retrievable, subsurface, surface-controlled, tubing safety valve for pumpdown operations for greater safety and reliability that can be pumped around a short radius curvature.
Another object of this invention is to provide a pumpdown, retrievable, subsurface, surface-controlled, tubing safety valve which permits the use of a plurality of springs to increase the force baising the valve closed and which may be pumped around a short radius curvature.
It is an object of this invention to provide a pumpdown, retrievable, subsurface, injection safety valve which includes a high force generating spring baising means and which can be pumped through a short radius curvature.
Another object of this invention is to provide a pumpdown, retrievable, subsurface, injection safety valve which includes a plurality of springs to bias the valve closed and which can be pumped through a short radius curvature.
Another object of this invention is to provide a spring closing, retrievable, subsurface, injection safety valve for pumpdown operations for greater safety and reliability that can be pumped around a short radius curvature.
Another object of this invention is to provide a pumpdown, retrievable, subsurface, injection safety valve which permits the use of a plurality of springs to increase the force biasing the valve closed and which may be pumped around a short radius curvature.
These and other objects, and features of advantages, of this invention will be apparent from the drawings, the detailed description and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings wherein like numerals indicate like parts and wherein illustrative embodiments of this invention are shown:
FIG. 1 is a schematic sectional view illustrating the use of a loop in a production string through which a pumpable tool train, including a safety valve, may be introduced into the well;
FIG. 2 is a sectional view of a portion of a bend in the production tubing illustrating a pumpdown tool train being pumped through the bend;
FIGS. 3A and 3B are quarter sectional views in continuation of a safety valve in accordance with this invention with the valve open;
FIG. 4 is a quarter sectional view of the safety valve of FIGS. 3A and 3B with the valve closed; and
FIGS. 5A and 5B are quarter sectional views in continuation of another safety valve in accordance with this invention with the valve open.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, a typical oil or gas well W at the bottom B of a body of water is illustrated. The production tubing T extends from a suitable production platform (not shown) along the bottom B, forms a loop L, and extends through the well W. The loop L is suitably supported and has a preselected radius of curvature which permits tool trains, safety valves, and other equipment to be pumped therethrough into the production string T within the well W.
The radius of curvature of the loop L, even though large enough to accommodate most individual tools, is not large enough to accommodate a straight train of tools. Each individual tool in the train is pivotally interconnected with other tools as shown in FIG. 2. The pivotal connecting provides longitudinal flexibility which is standard for use in pumpdown trains. The pumpdown train, generally indicated at 10, in FIG. 2 is within a string 12. Each of the components of the train 10 is pivotally connected to the other components so that the train 10 will easily pass through the spring 12. As shown, the train 10 includes a pair of piston pumpdown locomotives 16, jarring means 18, latching means 20, and a safety valve. The safety valve is divided into a valve section 22 and the spring force exerting sections 24.
The detail structure of one embodiment of a safety valve is shown in FIGS. 3A, 3B, and 4 with the valve illustrated as if it were landed within a landing nipple (not shown) of the production tubing. This safety valve is a pumpdown, retrievable, surface controlled, subsurface tubing safety valve.
The valve section 22 (see FIG. 3A) comprises valve housing means 26, valve member means 28 and means responsive to control pressure adapted to move valve member means 28.
The valve housing means, generally indicated at 26, makes up one short section of the pumpdown tool train and includes interconnected sections 26a, 26b, and 26c. The valve housing means 26 has a bore 30 through which fluids may flow. Surrounding valve housing means 26 is packer means 32 adapted to seal with the inner wall of the landing nipple (not shown).
Valve member means 28 is positioned within the bore 30 of housing means 24, and is adapted to move between positions opening and closing the bore 30 to permit the block flow through the tubing. The illustrated valve member means 28 is a ball valve member, movable about pin means 34 and is shown opening the bore 30 in FIG. 3A and is shown closing the bore 30 in FIG. 4.
The valve section 22 includes means responsive to control pressure adapted to move valve member means 28 to a position opening the bore 30. This means may include chamber means 36 having a pressure responsive means 38 adapted to move operator means 40. Chamber means 36 is formed between valve housing means 26 and operator means 40. Pressure responsive means 38 is carried by operator means 40, forms a portion of chamber means 36, and is adapted to move operator means 40 when chamber means 36 is pressurized. Operator means, generally indicated at 40, includes interconnected sections 40a and 40b and engages valve member means 28 to move valve member means 28 to a position opening the bore 30 when the chamber means 36 is pressurized (see FIG. 3A).
The valve section 22 also includes means adapted to move valve member means 28 to a position closing the bore 30. This valve moving means includes tube means 42 and cage means 44. Tube means 42 transmits the force of the force exerting sections 24 to the valve section 22 so that valve member means 28 can be biased to a position closing the bore 30. Tube means 42 also engages cage means 44 which in turn engages operator means 40. To permit tube means 42 and cage means 44 to move axially within housing means 26 and transmit the force of the force exerting sections 24 to operator means 40, cage means 44 surrounds valve member means 28 and includes slot means 46 to permit movement of cage means 44 around pin means 34.
One or more force exerting sections 24, provide the biasing force tending to move the valve member means 28 to a position closing the bore 30. A plurality of these sections 24 may be interconnected, with one of them connected to the valve section 22, in a manner hereinafter explained, to provide as much biasing force as is desired.
Each force exerting section 24 includes tubular mandrel means 48, movable sleeve means 50, and spring biasing means 52.
The elongate tubular mandrel means, generally indicated at 48, provides another short portion of the valve train 10. It includes interconnected sections 48a and 48b.
Disposed within tubular mandrel means 48 is sleeve means 50. Sleeve means 50 is adapted to move axially within the mandrel means 48 and functions to transmit the force of spring biasing means 52.
Spring biasing means 52 provides the biasing force of the force exerting section 24 and biases sleeve means 50 to a first, upward position with respect to tubular mandrel means 48. Spring biasing means 52 is disposed between shoulder means 54 of tubular mandrel means 48 and shoulder means 56 of sleeve means 50.
In accordance with this invention swivel connecting means interconnect the valve section 22 and one force exerting section 24. Articulating connecting means interconnect each of the force exerting sections. These connecting means permit the valve section and force exerting sections to be joined into a valve train 10 and pumped through a curvature of the well tubing. Through these connecting means, extend means for permitting the transmission of the spring biasing force generated by the force exerting sections 24 to the valve section 22.
Swivel connecting means, generally indicated at 58, may comprise a universal ball and socket joint. Ball socket means may be formed within the end of either valve housing means 26 or tubular mandrel means 48. Tubular ball member means would then be connected to the end of the other of valve housing means 26 and tubular mandrel means 48 and includes a ball portion adapted to be received within the socket means. Since for a pumpdown tool train it is customary to have all male connections point upwards, the tubular ball member means, generally indicated at 60, includes an upwardly directed tubular stem portion 62 having male threads 64 to connect it to the lower end of housing means 26. The tubular ball member means 60 also includes a ball portion 66 adapted to be received within ball socket means 68 formed within the upper end of tubular mandrel means 48.
Articulating connecting means, generally indicated at 70, is formed like swivel means. It too may comprise a ball and socket joint including a tubular ball member means, generally indicated at 72, having an upwardly directed tubular stem portion 74 threaded into the lower end of one tubular mandrel means 48' and a ball portion 76 adapted to be received within ball socket means 78 formed within the upper end of another tubular mandrel means 48".
To transmit the force of force exerting section 24 to valve section 22, one of the sleeve means 50 and the tube means 42 extends through swivel connecting means 58 and engages the other of said sleeve means 50 and said tube means 42. Since swivel connecting means 58 permits articulation of the valve section 22 with respect to the force exerting section 24, means are provided to permit the continued engagement of said sleeve means 50 and said tube means 42 during such articulation. Thus, associated with each of said sleeve means 50 and said tube means 42 are means for engaging the other during articulation.
Because of the structual arrangement of the swivel connecting means 58, the transmission of forces from force exerting section 24 to valve section 22 is accomplished by having tube means 42 extend from within valve section 22 through swivel connecting means 58 to within tubular mandrel means 48 where it engages sleeve means 50. The engaging means associated with the sleeve means 50 comprises a flange 80 on the upper end of sleeve means 50 having an upward facing spherical shaped surface 82 which is adapted to be engaged by the lower end of tube means 42. The engaging means of tube means 42 comprises a mating spherical shaped surface 84 on the lower end of tube means 42 adapted to engage sleeve means 50. Preferably, the spherical shaped surface 82 and the mating spherical shaped surface 84 are covered with a material such as polytetrafluoroethylene to minimize friction between them.
Because tube means 42 projects beyond swivel connecting means 58 to within tubular mandrel means 48 to engage sleeve means 50, the transmission of forces from force exerting section 24 to valve section 22 occurs independently of the axial alignment of valve section 22 and force exerting section 24. To assure that tube means 42 and sleeve means 50 are in continued engagement when valve section 22 and force exerting section 24 are not aligned, the centerpoint of spherical shaped surface 82, mating spherical shaped surface 84, and swivel connecting means 58 are substantially the same.
So that when force exerting sections 24 are joined together by articulating connecting means 70, the force of each force exerting section 24 is applied in series to another force exerting section 24 and ultimately to valve section 22, a sleeve means 50 extends through each articulating connecting means 70 to within another force exerting section where it is engaged by another sleeve means. Thus, like tube means 42, one sleeve means 50' extends from within its force exerting section 24' through articulating connecting means 70 to within another force exerting section 24" where it is engaged by another sleeve means 50". Associated with each of such sleeve means 50' and 50" are engaging means such as the upward facing spherical shaped surface 82" on a flange 80" of sleeve means 50; and a downward facing mating spherical shaped surface 86 on the lower end of sleeve means 50'. These surfaces may also be covered with polytetraflouroethylene and their centerpoint is also substantially the same as the centerpoint of articulating connecting means 70.
For the lowermost force exerting section 24'", the sleeve means 50'" need not extend beyond the lower end of tubular mandrel means 48'". However, so that all the sleeve means 50 may be manufactured alike, a lower sub 48'"c may be attached to and form a portion of tubular mandrel means 48'" to protect the lower end of sleeve means 50'".
With such an arrangement of tube means 42 extending through the swivel connecting means 58 and sleeve means 50 extending through the articulating connecting means 70, the force of each spring biasing means 52 is exerted on the sleeve means 50 of its section and is transmitted through another sleeve means 50 and through tube means 42 to valve section 22. When sleeve means 50 are moved to their first position with respect to tubular mandrel means 48 by spring biasing means 52, tube means 42 has moved operator means 40 to a position wherein valve member means 28 closes the bore 30.
In operation, the valve train 10 including the valve section 22 and at least one force exerting section 24 maybe pumped through a tubing having a curvature and landed in a nipple to provide a subsurface, surface-controlled tubing safety valve. The valve train 10 would also include a latching mandrel (not shown in FIGS. 3A and 3B and FIG. 4) pivotally connected to the upper end of valve section 22 by a universal joint comprising socket means 88 at the upper end of valve housing means 24 and ball member means 90 threaded into the lower end of the latching means 20.
When landed in the landing nipple (not shown) the valve section 22 can be controlled by fluid in a conduit extending from the surface to the landing nipple (not shown). A seal surrounding the latching mandrel will permit pressurized hydraulic control fluid to flow through the conduit port 92 and into chamber means 36. When chamber means 36 is pressurized, valve operator means 40 moves to the position shown in FIG. 3A and moves valve member means 28 to a position opening the bore 30.
When the control pressure is relieved, the force exerted by spring biasing means 52 of the force exerting sections 24 is transmitted through the sleeve means 50 and tube means 42 to move valve member means 28 to a position closing the bore 30 (see FIG. 4). The valve may include as many interconnected force exerting sections 24 as are necessary to exert a force sufficient to overcome the hydrostatic head of fluid present in the control conduit.
The detailed structure of a second embodiment of a safety valve is shown in FIGS. 5A and 5B, with the valves illustrated as if it were landed within a landing nipple (not shown) of the production tubing. This safety valve is a pumpdown, retrievable, subsurface injection valve. The valve section 100 (see FIG. 5A) comprises valve housing means 102 and valve member means 104.
The valve housing means, generally indicated at 102, makes up on short section of the pumpdown tool train and includes interconnected sections 102a and 102b. The valve housing means 102 has a bore 106 and port means 108 providing a fluid flow path through the valve section 100. Surrounding the valve housing means 102 is packer means 110 adapted to seal with the inner wall of the landing nipple (not shown).
Valve member means 104 is positioned within valve housing means 102 and is adapted to move longitudinally therein between a position engaging valve seat means 112 to close the flow path and a position removed from valve seat means 112 to open the flow path. Valve member means 104 is moved to its position engaging valve seat means 112 by the force transmitted to the valve section 100 from the force exerting section 124.
The valve may include as many interconnected force exerting sections 124 as is necessary to exert a force sufficient to overcome the hydrostatic head of fluid present within the well tubing.
The force exerting sections 124 are the same as the force exerting sections 24 of the previous embodiment. The various compenents thereof have been designated with numerals that correspond to the numeral designation of the previous embodiments with the addition of the prefix 1.
Swivel connecting means 158 interconnects the valve section 100 and one force exerting section 124. The swivel connecting means 158 is also the same as the swivel connecting means of the previous embodiment and its components have also been designated with numberals which correspond to the designation of the components of the previous embodiment with the addition of the prefix 1.
To transmit the force of the force exerting section 124 to the valve section 100 bar means 114 extends through swivel connecting means 158 to within tubular mandrel means 148 and engages sleeve means 150. Since swivel connecting means 158 permits articulation of the valve section 100 with respect to the force exerting section 124, bar means 114 and sleeve means 150 include engaging means to permit their continued engagement during such articulation. The engaging means associated with bar means 114 comprises a mating spherical shaped surface 116 on the lower end of bar means 114 which is adapted to engage the spherical shaped surface 182 of sleeve means. Preferably, the mating spherical shaped surface 116 is also covered with a material such as polytetrafluoroethylene to minimize the friction between it and spherical shaped surface 182.
The transmission of forces from force exerting section 124 to valve section 100 occurs independent of the axial alignment of valve section 100 and force exerting section 124. To assure that bar means 114, and sleeve means 150 are in continued engagement when the valve section 100 and the force exerting section 124 are not aligned, the centerpoint of spherical shaped surface 182, mating spherical shaped surface 116, and swivel connecting means 158 are substantially the same.
When sleeve means 150 has moved to its first position with respect to tubular mandrel means 148, bar means 114 valve member means 104 to a position engaging valve seat means 112 and closing the valve section flow path.
In operation, after the valve section 100 has been landed in a landing nipple (not shown) the valve controls flow through the tubing bore. When fluid is injected down the tubing bore, the pressure of the injected fluid acting across valve member means 104, moves it away from valved seat means 112 thereby enabling fluid flow through the valve section 100. The force of the injected fluid, necessarily acts against the force transmitted to the valve section 100 from the force exerting sections 124. When injection of fluid is ceased, the force exerted by spring biasing means 152 of the force exerting sections 124 is transmitted to the valve section 100 to move the valve member means 104 to its position engaging valve seat means 112 and closing the flow path. The valve may include as many interconnected force exerting sections 124 as are necessary to exert a force sufficient to overcome the hydrostatic head of fluid present in the well tubing.
From the foregoing it may be seen that the objects of this invention have been attained. A reliable, fail safe, subsurface, safety valve, that may be pumped through a radius of curvature, has been provided. Positive force, exerted by springs, is used to urge the valve member to a position blocking fluid flow. However, the sections of the valve are not long and the valve may be pumped through a loop or tubing having a curve. The sections, including the valve section and one or more force exerting sections, are interconnected by connecting means which permit the train to pass through the curved portion of the tubing. At the same time, the force of springs within the force exerting sections is transmitted through the connecting means at all times to urge the valve member to a closed position.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made within the scope of the appended claims without departing from the spirit of the invention. | Disclosed is a pumpdown, retrievable, subsurface, safety valve for use in a well. The valve comprises a valve section including a valve member to control flow through the well tubing and one or more force exerting sections urging the valve member to a position blocking flow. The valve section and force exerting sections are interconnected. This abstract is neither intended to define the invention of the application which, of course, is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way. | 4 |
FIELD OF THE INVENTION
This invention relates to a semiconductor dynamic random access memory device and, more particularly, to a dynamic random access memory cell incorporated in the semiconductor dynamic random access memory device.
DESCRIPTION OF THE RELATED ART
The semiconductor dynamic random access memory device has been increased in integration density, and miniaturization of the storage capacitor supports the enhancement of the integration density. Of course, the development of the integration density does not allow the miniaturized storage capacitor to decrease the accumulated electric charge, and various approaches have been proposed. One of the approaches is a three-dimensional structure, and the trench structure and the stacked structure effectively increase the electric charge accumulated in the storage capacitor without increase of the occupation area. Another approach is a thin dielectric layer, and the dielectric film structure is equivalent to 5 nanometers of a silicon oxide film for the stacked capacitor of a 16 mega-bit semiconductor dynamic random access memory device.
Description is firstly made on a typical example of the process sequence for the dynamic random access memory device equipped with the stacked capacitor type memory cells with reference to FIG. 1A to 1D of the drawings.
The prior art process sequence starts with preparation of a p-type silicon substrate 1, and a thick field oxide layer 2 is selectively grown on the major surface of the p-type silicon substrate 1. The thick filed oxide layer 2 defines an active area in the major surface.
The active area is thermally oxidized for growing a gate oxide film 3, and a polysilicon layer is deposited over the entire surface of the structure. The polysilicon layer is patterned into a word line through lithographic techniques, and a part of the word line forms a gate electrode 4 on the thin gate oxide film 3. Using the gate electrode 4 as a mask, n-type dopant impurity is ion-implanted into the active area, and an n-type source region 5a and an n-type drain region 5b are formed in the active area in a self-aligned manner with the gate electrode 4.
An inter-level insulating layer 6 is deposited over the entire surface of the structure, and an appropriate mask layer (not shown) is formed on the inter-level insulating layer 6. The mask layer exposes an area over the n-type source region 5a. Using the mask layer, the inter-level insulating layer 6 and the thin gate oxide film 3 are partially etched away, and a contact hole 6a is formed through the inter-level insulating layer 6 and the thin gate oxide film 3 as shown in FIG. 1A.
Polysilicon is deposited over the entire surface of the structure, and n-type dopant impurity is diffused or ion-implanted into the polysilicon. The polysilicon doped with the n-type dopant impurity forms a doped polysilicon layer 7. The doped polysilicon fills the contact hole 6a, and the doped polysilicon layer 7 is held in contact with the n-type source region 5a. The resultant structure at this stage is illustrated in FIG. 1B. In this instance, the doped polysilicon 7 is 10 20 atoms/cm 3 in dopant concentration.
The polysilicon layer 7 is patterned through lithographic techniques into an accumulating electrode 7a, and a silicon nitride film 8 is deposited over the entire surface of the structure through a low-pressure chemical vapor deposition. The surface portion of the silicon nitride film 8 is converted into a silicon oxide film 9 through a wet oxidation, and the resultant structure at this stage is illustrated in FIG. 1C. The silicon nitride film 8 and the silicon oxide film 9 form in combination a dielectric film structure, and the dielectric film structure is equivalent in thickness to a silicon oxide film of 5 nanometers thick. The silicon oxide film is assumed to have the dielectric constant of 3.82.
Polysilicon is deposited over the entire surface of the structure though a low-pressure chemical vapor deposition, and n-type dopant impurity is introduced into the polysilicon. As a result, a doped polysilicon layer is formed on the silicon oxide film 9, and is patterned into a counter electrode 10 as shown in FIG. 1D.
Though not shown in the drawings, a second inter-level insulating layer is deposited over the entire surface of the structure, and a bit contact hole is formed through the inter-level layers. A bit line is formed on the second inter-level insulating layer, and is held in contact through the bit contact hole to the n-type drain region 5b.
The gate oxide film 3, the gate electrode 4, the n-type source region 5a, the n-type drain region 5b as a whole constitute an n-channel enhancement type switching transistor SW1, and the accumulating electrode 7a, the silicon nitride film 8, the silicon oxide film 9 and the counter electrode 10 form in combination a stacked-type storage capacitor CP1. The series combination of the n-channel enhancement type switching transistor SW1 and the stacked type storage capacitor CP1 serves as the stacked type dynamic random access memory cell.
In operation, the counter electrode 10 is applied with an intermediate voltage level as high as a half of the power voltage level Vcc, and the n-channel enhancement type switching transistor SW1 turns on for storing a data bit in the storage capacitor. The two logic levels of the stored data bit are represented by the power voltage level Vcc and the ground voltage level.
A problem is encountered in the prior art dynamic random access memory cell in that the dielectric film structure can not decrease the thickness less than the equivalent thickness of 5 nanometers. If the dielectric film structure is decreased in the equivalent thickness less than 5 nanometers, leakage current tends to flow therethrough, and the accumulated electric charge is lost in short time period.
SUMMARY OF THE INVENTION
It is therefore an important object of the present invention to provide a semiconductor dynamic random access memory cell which is free from the leakage current between an accumulating electrode and a counter electrode.
The present inventor contemplated the leakage current, and noticed that the potential barrier between the Fermi level of the n-type polysilicon and the bottom edge of the conduction band of the silicon oxide film promoted a direct tunneling current. In detail, the prior art storage capacitor CP1 created the energy structure shown in FIG. 2 in thermal equilibrium, and the band gap in the silicon oxide and the band gap of the silicon nitride were about 8 eV and 5 eV. The potential gap between the Fermi level Ef and the bottom edge Ec of the conduction band of the silicon oxide was about 3 eV, and the potential gap between the silicon oxide and the silicon nitride was about 1 eV. The dielectric film structure was equivalent to the silicon oxide film SO of 5 nanometer thick, and the energy structure shown in FIG. 2 was modulated to the energy structure shown in FIG. 3A.
When bias voltage of 1 volt was applied to the accumulating electrode 7a with respect to the counter electrode 10, the Fermi level of the n-type polysilicon for the counter electrode 10 was aligned with a certain energy level in the conduction band of the n-type polysilicon for the accumulating electrode 7a as shown in FIG. 3B, and the direct tunneling phenomenon was much liable to take place in spite of the potential gap of 3 eV between the n-type polysilicon and the silicon oxide.
On the other hand, if bias voltage of -1 volt was applied to the accumulating electrode 10 with respect to the counter electrode 7a, the Fermi level of the n-type polysilicon for the accumulating electrode 7a was aligned with a certain energy level in the conduction band of the n-type polysilicon for the counter electrode 10 as shown in FIG. 3C, and the direct tunneling phenomenon tended to take place in spite of the potential gap of 3 eV between the silicon oxide and the n-type polysilicon.
Therefore, the present inventor concluded that the combination of the n-type polysilicon layers on both sides of the silicon oxide film be avoided.
To accomplish the object, the present invention proposes to arrange the energy band structure of a storage capacitor in such a manner that the Fermi level of a semiconductor substance for at least either electrode falls within the forbidden band of a semiconductor substance for the other electrode or alternatively increase a potential barrier height between an electrode and a dielectric film structure.
In accordance with the present invention, there is provided a semiconductor dynamic random access memory cell fabricated on a semiconductor substrate, comprising: a) a switching transistor having a first impurity region formed in a surface portion of the semiconductor substrate and coupled to a signal line, and a second impurity region formed in another surface portion of the semiconductor substrate and connectable to the first impurity region; and b) a storage capacitor having an accumulating electrode electrically connected to the second impurity region in an ohmic manner, a dielectric film structure covering the accumulating electrode, and a counter electrode held in contact with the dielectric film structure in an opposing relation to the accumulating electrode, at least one of the accumulating electrode and the counter electrode having a p-type polysilicon held in contact with the dielectric film structure.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the semiconductor dynamic random access memory cell according to the present invention will be more clearly understood from the following description taken in conjunction with the accompanying drawings in which:
FIGS. 1A to 1D are cross sectional views showing the prior art process sequence for fabricating the stacked-type dynamic random access memory cell;
FIG. 2 is an energy band diagram showing the band structure of the prior art stacked type storage capacitor in thermal equilibrium without a bias;
FIGS. 3A to 3C are energy band diagrams showing the band structure of the prior art stacked type storage capacitor in thermal equilibrium;
FIG. 4 is a cross sectional view showing the structure of a semiconductor dynamic random access memory cell according to the present invention;
FIGS. 5A to 5D are cross sectional views showing a process sequence for fabricating the semiconductor dynamic random access memory device according to the present invention;
FIG. 6 is an energy band diagram showing the band structure of the stacked type storage capacitor incorporated in the semiconductor dynamic random access memory device in thermal equilibrium;
FIGS. 7A to 7C are energy band diagrams showing the band structure of the stacked type storage capacitor under different bias conditions;
FIG. 8 is a cross sectional view showing the structure of another semiconductor dynamic random access memory cell according to the present invention;
FIGS. 9A to 9C are energy band diagrams showing the band structure of the stacked type storage capacitor incorporated in the semiconductor dynamic random access memory device shown in FIG. 8 under different bias conditions;
FIG. 10 is a cross sectional view showing the structure of yet another semiconductor dynamic random access memory device according to the present invention; and
FIGS. 11A to 11C are energy band diagrams showing the band structure of the stacked type storage capacitor incorporated in the semiconductor dynamic random access memory device shown in FIG. 10 under different bias conditions
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
Referring to FIG. 4 of the drawings, a semiconductor dynamic random access memory cell is fabricated on a p-type silicon substrate 21, and a thick field oxide layer 22 defines an active area in the major surface of the p-type silicon substrate 21. The active area assigned to the semiconductor dynamic random access memory cell is not wider than the active area assigned to the prior art semiconductor dynamic random access memory cell.
In the active area, an n-type source region 23a and an n-type drain region 23b are formed in the active area, and are spaced apart from each other by a channel region. The channel region is covered with a gate insulating film 24, and a gate electrode forming a part of a word line is patterned on the gate insulating film 24 in a self-aligned manner with the n-type source region. 23a and the n-type drain region 23b.
The n-type source region 23a, the n-type drain region 23b, the channel region, the gate insulating film 24 and the gate electrode 25 as a whole constitute an n-channel enhancement type switching transistor SW2.
A first inter-level insulating layer 26 covers the n-channel enhancement type switching transistor SW2 and other exposed layers, and a contact hole 26a is formed in the first inter-level insulating layer 26 for exposing a part of the n-type source region 23a. A conductive metal block 26b plugs the contact hole 26a, and an ohmic contact is formed between the n-type source region 23a and the conductive metal block 26b. In this instance, the conductive metal block 26b is formed of tungsten, molybdenum, copper, aluminum or titanium nitride.
An accumulating electrode 27 of p-type polysilicon is formed on the first inter-level insulating layer 26, and is held in contact with the conductive metal block 26b in the contact hole 26a. As a result, an ohmic contact is formed between the conductive metal block 26b and the accumulating electrode 27, and current bi-directionally flows through the ohmic contacts between the n-type source region 23a and the accumulating electrode 27.
The accumulating electrode 27 is covered with a silicon nitride film 28a which in turn is covered with a silicon oxide film 28b. The silicon nitride film 28a and the silicon oxide film 28b form in combination a dielectric film structure 28.
The dielectric film structure 28 is overlain by a counter electrode 29 of p-type polysilicon, and the counter electrode 29 is biased with an intermediate voltage level Vm. The intermediate voltage level Vm is regulated to a half of a positive power voltage level Vcc, and the positive power voltage level Vcc is about 2 volts.
The accumulating electrode 27 of the p-type polysilicon, the dielectric film structure 28 and the counter electrode 29 of the p-type polysilicon as a whole constitute a stacked type storage capacitor CP2, and the semiconductor dynamic random access memory cell is implemented by the series circuit of the n-channel enhancement type switching transistor SW2 and the stacked type storage capacitor CP2.
The storage capacitor CP2 is covered with a second inter-level insulating layer 30, and a bit line BL is patterned on the second inter-level insulating layer 30. The bit line BL is coupled through a contact hole (not shown) to the n-type drain region 23b, and a data bit DB is transferred from the bit line BL through the n-channel enhancement type switching transistor SW2 to the accumulating electrode 27. The two logic levels of the stored data bit DB are corresponding to the positive power voltage level Vcc and the ground voltage level in the accumulating electrode 27.
A process sequence for fabricating the semiconductor dynamic random access memory device is hereinbelow described with reference to FIGS. 5A to 5D of the drawings. The process sequence starts with preparation of the p-type silicon substrate 21, and the thick field oxide layer 22 is selectively grown on the major surface of the p-type silicon substrate 21. The thick filed oxide layer 22 defines the active area in the major surface, and the semiconductor dynamic random access memory cell is fabricated on the active area.
The active area is thermally oxidized for growing the gate insulating film 24, and a polysilicon layer is deposited over the entire surface of the structure. The polysilicon layer is patterned into a word line through lithographic techniques, and a part of the word line on the thin gate insulating layer 24 serves as the gate electrode 25. Using the gate electrode 25 as a mask, n-type dopant impurity is ion-implanted into the active area, and the n-type source region 23a and the n-type drain region 23b are formed in the active area in a self-aligned manner with the gate electrode 25.
The first inter-level insulating layer 26 is deposited over the entire surface of the structure, and an appropriate mask layer (not shown) is formed on the first inter-level insulating layer 26. The mask layer exposes an area over the n-type source region 23a. Using the mask layer, the inter-level insulating layer 26 and the thin gate oxide film 24 are partially etched away, and a contact hole 26a is formed through the inter-level insulating layer 26 and the thin gate oxide film 24 as shown in FIG. 5A.
The conductive metal is selectively grown in the contact hole 26a, and the conductive metal block 26b plugs the contact hole 26a. Alternatively, the conductive metal is sputtered on the entire surface of the structure, and the conductive metal film is uniformly etched away so as to leave the conductive metal block in the contact hole 26a. The resultant structure at this stage is illustrated in FIG. 5B.
Polysilicon is deposited over the entire surface of the structure, and p-type dopant impurity such as, for example, boron is thermally diffused or ion-implanted into the polysilicon. The polysilicon doped with the p-type dopant impurity forms the p-type polysilicon layer 27a, and is held in contact with the conductive metal block 26b. The resultant structure at this stage is illustrated in FIG. 5C. In this instance, the p-type polysilicon layer 27a is 10 20 atoms/cm 3 in dopant concentration.
The p-type polysilicon layer 27a is patterned through lithographic techniques into the accumulating electrode 27, and the silicon nitride film 28a is deposited over the entire surface of the structure through a low-pressure chemical vapor deposition. The surface portion of the silicon nitride film 28a is converted into the silicon oxide film 28b through a wet oxidation, and the resultant structure at this stage is illustrated in FIG. 5D. The silicon nitride film 28a and the silicon oxide film 28b form in combination the dielectric film structure 28, and the dielectric film structure 28 is equivalent in thickness to a silicon oxide film less than 5 nanometers thick.
Polysilicon is deposited over the entire surface of the structure though a low-pressure chemical vapor deposition, and p-type dopant impurity is introduced into the deposited polysilicon at *×10 ** /cm 3 . As a result, a p-type doped polysilicon layer is formed on the dielectric film structure 28, and is patterned into the counter electrode 29 by using the lithographic techniques.
The second inter-level insulating layer 30 is deposited over the entire surface of the structure, and a bit contact hole (not shown) is formed through the first and second inter-level layers. The bit line BL is formed on the second inter-level insulating layer 30, and is held in contact through the bit contact hole to the n-type drain region 23b.
Turning to FIG. 6 of the drawings, the stacked type storage capacitor CP2 creates an energy structure in thermal equilibrium, and Ec and Ef are representative of the bottom edge of the conduction band and the Fermi level. The silicon oxide and the silicon nitride have an energy band gap about 9 eV and an energy band gap about 5 eV, respectively, and a potential gap about 1 eV is produced between the bottom edge Ec of the silicon oxide and the bottom edge Ec of the silicon nitride.
Since the p-type polysilicon is doped so heavy that the Fermi level Ef of the p-type polysilicon is very close to the top edge of the valence band, and the Fermi level Ef of the p-type polysilicon is spaced from the bottom edge of the conduction band of the silicon oxide by about 1.1 eV. For this reason, the p-type polysilicon and the silicon oxide form a potential gap of about 4 eV between the bottom edge Ec of the silicon oxide and the Fermi level Ef of the p-type polysilicon, and is larger in magnitude than that of the prior art.
The dielectric film structure 28 is equivalent to a silicon oxide film SO with a different thickness, and the energy band structure shown in FIG. 6 is assumed to be equivalent to an energy band structure shown in FIG. 7A. While the accumulating electrode 27 is equal in potential level to the counter electrode 29, the energy band gap about 4 eV provides a potential barrier against carriers.
As described hereinbefore, the counter electrode 29 is biased with the intermediate voltage level Vm about Vcc/2 or 1 volt at all times, and the accumulating electrode 27 is varied in potential level between 0 volt and 2 volts.
When the accumulating electrode 27 is biased to the counter electrode 29 with 1 volt, the energy structure is modified as shown in FIG. 7B, and the Fermi level of the p-type polysilicon for the counter electrode 29 falls within the forbidden band of the p-type polysilicon for the accumulating electrode 27 as shown in FIG. 7B, because the bias voltage is less than 1.1 volts calculated from the energy gap between the Fermi level of the p-type polysilicon and the bottom edge Ec of the silicon oxide. For this reason, the direct tunneling phenomenon hardly takes place, and direct tunneling current is effectively restricted in the storage capacitor CP2.
On the other hand, when the accumulating electrode 27 is biased to the counter electrode 29 with -1 volt, the energy structure is modified as shown in FIG. 7C, and the Fermi level of the p-type polysilicon for the accumulating electrode 27 falls within the forbidden band of the p-type polysilicon for the counter electrode 29 as shown in FIG. 7C. For this reason, the direct tunneling phenomenon hardly takes place, and direct tunneling current is effectively restricted in the storage capacitor CP2.
The probability P of the direct tunneling is expressed as
P=exp [-T (BH).sup.1/2 ]
where T is the thickness of the equivalent dielectric film SO and BH is the potential barrier height. If the equivalent dielectric film SO of the first embodiment is equal in thickness to the equivalent dielectric film of the prior art, the reduction ratio R of the leakage current is calculated as
R=exp [-(4).sup.1/2 ]/exp[-3(3).sup.1/2 ]=0.77
If the same leakage current is allowed, the equivalent dielectric film SO is decreased in thickness to [(3) 1/2 /(4) 1/2 ]=0.87 with respect to the equivalent dielectric film of the prior art.
In this instance, the counter electrode 29 is formed of the p-type polysilicon. However, a lamination of the p-type polysilicon layer and metal layer is available for the counter electrode 29.
As will be understood from the foregoing description, the p-type polysilicon layers causes the Fermi level to fall within the forbidden band under the bias conditions, and the direct tunneling phenomenon hardly takes place. As a result, the dielectric film structure is decreased in thickness, and the storage capacitor CP2 is increased in capacitance without sacrifice of the occupation area.
Second Embodiment
Turning to FIG. 8 of the drawings, another semiconductor dynamic random access memory cell is fabricated on a p-type silicon substrate 31, and largely comprises an n-channel enhancement type switching transistor SW3 and a stacked type storage capacitor CP3 coupled in series. A thick field oxide layer 32 defines an active area assigned to the semiconductor dynamic random access memory cell, and the active area is not wider than the active area assigned to the prior art semiconductor dynamic random access memory cell.
The switching transistor SW3 comprises an n-type source region 33a, an n-type drain region 33b, a gate insulating film 34 and a gate electrode 35 forming a part of a word line. Though not shown in FIG. 8, the n-type drain region 33b is electrically connected with a bit line, and the n-type drain region 33b is electrically connected to and isolated from the n-type source region 33a depending upon the potential level on the word line.
The stacked type storage capacitor CP3 comprises an accumulating electrode 36 of n-type polysilicon with dopant concentration of *×10 ** atoms/cm 3 , a dielectric film structure 37 covering the accumulating electrode 36 and a counter electrode 38 of p-type polysilicon with dopant concentration of *×10 ** atoms/cm 3 . The n-type polysilicon forms an ohmic contact between the n-type source region 33a and the accumulating electrode 36, and the dielectric film structure 37 is implemented by the combination of a silicon nitride film 37a and a silicon oxide film 37b. The counter electrode 38 is held in contact with the dielectric film structure 37 in opposing relation to the accumulating electrode 36.
The dielectric film structure 37 is equivalent to a silicon oxide film SO different in thickness from the total thickness of the dielectric film structure, and the modified storage capacitor CP3' creates an energy band structure as shown in FIG. 9A in thermal equilibrium. The n-type polysilicon is doped so heavy that the Fermi level is very close to the bottom edge of the conduction band. Similarly, the p-type polysilicon is doped so heavy that the Fermi level is very close to the top edge of the valence band. For this reason, the bottom edge Ec of the conduction band and the top edge of the valence band are deleted from the energy band structure of the n-type polysilicon for the accumulating electrode 36 and the energy band structure of the p-type polysilicon for the counter electrode 38. The potential barrier of about 4 eV is created at the interface between the counter electrode 38 and the equivalent silicon oxide film SO or the dielectric film structure 37.
When the accumulating electrode 36 is positively biased to the counter electrode 38 with 1 volt, the energy band structure is changed as shown in FIG. 9B, and the Fermi level Ef of the p-type polysilicon falls within the conduction band of the n-type polysilicon. However, the increased potential barrier about 4 eV decreases the probability P of the direct tunneling, and decreases one of the amount of direct tunneling current and the thickness of the dielectric film structure 37.
On the other hand, if the accumulating electrode 36 is negatively biased to the counter electrode 38 with -1 volt, the energy band structure is changed as shown in FIG. 9C, and the Fermi level Ef of the n-type polysilicon falls within the forbidden band of the p-type polysilicon. For this reason, the direct tunneling hardly takes place.
The dielectric film structure is decreased to 87 per cent of the dielectric film structure of the prior art semiconductor dynamic random access memory device.
Thus, the semiconductor dynamic random access memory device according to the present invention decreases the direct tunneling current without sacrifice of the occupation area. Moreover, the semiconductor dynamic random access memory device is fabricated through a process sequence simpler than that of the first embodiment, because the accumulating electrode 36 is directly held in contact with the n-type drain region 33a without a conductive metal block.
Third Embodiment
Turning to FIG. 10 of the drawings, yet another semiconductor dynamic random access memory device embodying the present invention is fabricated on a p-type silicon substrate 41, and largely comprises an n-channel enhancement type switching transistor SW4 and a stacked type storage capacitor CP4 coupled in series. A thick field oxide layer 42 defines an active area assigned to the semiconductor dynamic random access memory cell, and the active area is not wider than the active area assigned to the prior art semiconductor dynamic random access memory cell.
The switching transistor SW4 comprises an n-type source region 43a, an n-type drain region 43b, a gate insulating film 44 and a gate electrode 45 forming a part of a word line. Though not shown in FIG. 10, the n-type drain region 43b is electrically connected with a bit line, and the n-type drain region 43b is electrically connected to and isolated from the n-type source region 43a depending upon the potential level on the word line.
The n-channel enhancement type switching transistor SW4 is covered with an inter-level insulating layer 46, and a contact hole is formed in the inter-level insulating layer 46 for exposing the n-type source region 43a. A conductive metal block 47 plugs the contact hole, and form an ohmic contact with the n-type source region 43a.
The stacked type storage capacitor CP4 comprises an accumulating electrode 48 of p-type polysilicon with dopant concentration of *×10 ** atoms/cm 3 , a dielectric film structure 49 covering the accumulating electrode 48 and a counter electrode 50 of n-type polysilicon with dopant concentration of *×10 ** atoms/cm 3 . The p-type polysilicon forms an ohmic contact with the conductive metal block 47, and current bi-directionally flows between the n-type source region 43a and the accumulating electrode 48. The dielectric film structure 49 is implemented by the combination of a silicon nitride film 49a and a silicon oxide film 49b. The counter electrode 50 is held in contact with the dielectric film structure 49 in opposing relation to the accumulating electrode 48.
The dielectric film structure 49 is equivalent to a silicon oxide film SO different in thickness from the total thickness of the dielectric film structure, and the modified storage capacitor CP4' creates an energy band structure as shown in FIG. 11A in thermal equilibrium. The p-type polysilicon is doped so heavy that the Fermi level Ef is very close to the top edge Ev of the conduction band. Similarly, the n-type polysilicon is doped so heavy that the Fermi level Ef is very close to the bottom edge Ec of the conduction band. For this reason, the bottom edge Ec of the conduction band and the top edge of the valence band are deleted from the energy band structure of the n-type polysilicon for the counter electrode 50 and the energy band structure of the p-type polysilicon for the accumulating electrode 48. The potential barrier of about 4 eV is created at the interface between the counter electrode 38 and the equivalent silicon oxide film SO or the dielectric film structure 49.
When the accumulating electrode 48 is positively biased to the counter electrode 38 with 1 volt, the energy band structure is changed as shown in FIG. 11B, and the potential barrier is decreased to about 3 eV. However, Fermi level Ef of the n-type polysilicon falls within the forbidden band of the p-type polysilicon. As a result, the direct tunneling phenomenon hardly takes place.
On the other hand, if the accumulating electrode 48 is negatively biased to the counter electrode 50 with -1 volt, the energy band structure is changed as shown in FIG. 11C, and the potential barrier is increased to 4 eV as shown in FIG. 11C. The probability P is decreased, and the dielectric film structure is decreased to 87 per cent of the dielectric film structure of the prior art semiconductor dynamic random access memory device.
Thus, the semiconductor dynamic random access memory device according to the present invention decreases the direct tunneling current without sacrifice of the occupation area.
Although particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention.
For example, the impurity regions and the semiconductor layers of the dynamic random access memory cell according to the present invention are changed in the conductivity type from those of the above described embodiments, and the storage capacitor may be a plane type or another three-dimensional type such as, for example, a trench type or a stacked-trench type.
Moreover, the semiconductor dynamic random access memory cell may be incorporated in a function block of a large scale integration. | A storage capacitor incorporate in a semiconductor dynamic random access memory cell has an accumulating electrode of p-type polysilicon electricaly conencted to an n-type drain region of an associated switching transistor, a dielectric film structure covering the accumulating electrode and a counter electrode opposed through the dielectric film structure and formed of a p-type polysilicon, and the dielectric film structure is thinner than a critical thickness for a direct tunneling current by virtue of the wide potential barrier between the dielectric film structure and the p-type polysilicon and the Fermi level of the p-type polysilicon falling into the forbidden band of the other p-type polyslicon. | 7 |
BACKGROUND OF THE INVENTION
Prior rifle stocks have been made of wood or synthetic materials. Decorations and checkering have been carved, embossed or otherwise impressed in the stocks. Rifle stocks have also been made of plastic materials such as ABS (acrylonitrile-butadiene-styrene) polymers, phenol and nylon. Some plastic material stocks have carried patterns which simulate wood graining.
With synthetic stocks, excessive weight (compared to wood) has been a problem. Various lightening solutions have been attempted, but often at the expense of strength. Also, synthetic stock materials lack the warmth and "feel" of wood.
SUMMARY OF THE INVENTION
Broadly, the present invention is a rifle stock having its forearm, mid-stock and butt sections comprised of a one piece plastic structural framework together with attached insert panels. The plastic framework is a lightweight readily moldable structure consisting of web walls having thicknesses, spacing and openings to facilitate such fabrication. Alternatively, the framework can be made of two or more framework elements fastened together.
It is a feature that the framework has border recess areas for receiving panels of wood or other materials which panels are configured to fit into the recess areas and to be fastened to or urged against the framework recesses to strengthen the rifle stock and provide a more secure feel and pleasing appearance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a right side elevational view of the rifle stock of the present invention;
FIG. 2 is a plan view of the rifle stock;
FIG. 3 is a sectional view taken along line 3--3 of FIG. 1;
FIG. 4 is a sectional view taken along line 4--4 of FIG. 1;
FIG. 5 is a sectional view taken along line 5--5 of FIG. 1;
FIG. 6 is a sectional view taken along line 6--6 of FIG. 1;
FIG. 7 is a sectional view taken along line 7--7 of FIG. 1;
FIG. 8 is a sectional view taken along line 8--8 of FIG. 2;
FIG. 9 is an enlarged partial right side elevational view of a forward portion of the stock;
FIG. 10 is a sectional view taken along line 10--10 of FIG. 9;
FIG. 11 is a sectional view taken along line 11--11 of FIG. 8;
FIG. 12 is an enlarged partial right side elevational view of the rearward butt portion of the stock;
FIG. 13 is an enlarged partial right side elevational view of the mid-stock portion of the stock;
FIG. 14 is a rearward elevational view of the stock;
FIG. 15 is a sectional view taken along line 15--15 of FIG. 13;
FIG. 16 is a sectional view taken along line 16--16 of FIG. 12;
FIG. 17 is a sectional view taken along line 17--17 of FIG. 12;
FIG. 18 is a view taken along line 18--18 of FIG. 12;
FIG. 19 is a partial right side elevational view of the butt portion of an alternative embodiment of the stock;
FIG. 20 is a partial right side elevational view of the forearm portion of an alternative embodiment of the stock;
FIG. 21 is a view taken along line 21--21 of FIG. 19;
FIG. 22 is a sectional view taken along line 22--22 of FIG. 19;
FIG. 23 is a sectional view taken along line 23--23 of FIG. 20;
FIG. 24 is a sectional view taken along line 24--24 of FIG. 20;
FIG. 25 is a partial right side elevational view of a third embodiment of the stock;
FIG. 26 is a sectional view taken along line 26--26 of FIG. 29;
FIG. 27 is an exploded sectional view taken along line 27--27 of FIG. 25;
FIG. 28 is a sectional view taken along line 28--28 of FIG. 25;
FIG. 29 is a sectional view taken along line 29--29 of FIG. 25;
FIG. 30 is a partial exploded perspective view of the mid-stock portion of a fourth embodiment;
FIG. 31 is a partial exploded perspective view of the forearm portion of such embodiment;
FIG. 32 is a fifth embodiment in partial right side elevational view showing a butt stock mold recess receiving a cheek panel;
FIG. 33 is a sectional view taken along line 33--33 of FIG. 32;
FIG. 34 is a sectional view taken along line 34--34 of FIG. 32;
FIG. 35 is an end elevational view along lines 35--35 of FIG. 32;
FIG. 36 is a sixth embodiment in partial right side elevational view showing a butt stock mold recess and cheek panel;
FIG. 37 is a longitudinal sectional view of the butt stock taken through a vertical centerline of the butt stock of FIG. 36;
FIG. 38 is a sectional view taken along line 38--38 of FIG. 36; and
FIG. 39 is a sectional view taken along line 39--39 of FIG. 36.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the embodiment shown in FIGS. 1-18, rifle stock 8 includes forearm stock section 10, mid-stock section 11 and butt stock section 12. Stock 8 is integrally formed by injection molding or other fabrication technique. Stock 8 may also be made in frame elements and assembled using suitable connector means. Rifle stock 8 includes a continuous framework web structure 13 having numerous web walls 14 both vertically and horizontally positioned. The thickness and spacing of web walls 14 is such that they are readily formed using standard commercial fabricating techniques such as injection molding, lamination or other industrial process. The preferred materials are nylon, nylon-based materials, ABS, fiberglass or other suitable synthetic materials, herein referred to as "synthetic materials".
Preferably, the fabricated structure is formed using injection molding techniques in which mold cavities are sized, shaped and designed to provide ease of molding at speeds and economies in accordance with current practices in the injection molding industry. Web walls 14 have selected thicknesses and spaced recess openings consistent with ease of fabrication by injection molding as sought by this invention, leaving further required strength, rigidity and appearance to be accomplished by the use of insert panels and fastener means holding the inserts in place.
Butt stock web walls 14 include central vertical stock wall 14s and stock cylindrical wall 14c. Web walls 14 also include forearm left vertical wall portion 141, right vertical wall 14r and forearm base wall 14b (see FIGS. 4-7). Forearm stock walls 141 and 14r have pairs of panel-receiving wall recesses 15r, 16r and 151 and 161 having border portions 7r and 71 for receiving wooden insert panels 17r and 171. Recesses 15r, 16r, 151 and 161 are part of openings 18r, 181, 19r and 191 in the stock walls 14r and 141. Border portions 7r and 71 include angled-intersecting seat planes 7a and 7b. Walls 141 and 14r also include frame opening 18r, 181, and 19r, 191 to facilitate the molding operation and to reduce weight while still providing sufficient structural strength.
Fastener assembly 20 secures panels 17r and 171 in recesses 16r and 161 (see FIGS. 9 and 10). Fastener assembly 20 includes headed bolt 21 and threaded nut 22 which bolt and nut are nested in fastener-receiving panel indents 23 and 24, respectively, to provide a flush appearance. Panels 17r and 171 may be raised (rather than flush) if desired. Bolt 21 passes through opening 26a in spacer piece 26 (FIGS. 1 and 8). Fastener assembly 20 urges panels 17r and 171 in tensioned engagement against border portions 7r and 71 including seat planes 7a and 7b.
Insert panels 17r, 171 function to structurally strengthen framework web structure 13 and also function through color and texture, to provide a decorative quality to stock 8. Preferably panels 17r and 171 are made of wood but other similar materials or synthetic materials may also be used provided they afford required stiffness and the desired feel and appearance. Base web walls 14b include rifle mechanism mount openings 27 and 28 for mounting or otherwise securing the rifle mechanism (not shown) to stock 8 (FIG. 8). Base wall 14b also includes integrally-formed trigger guard 31. Also shown in FIG. 11 is wall cutout portion 42 in right forearm wall 14r to accommodate the rifle bolt (not shown).
Turning to FIGS. 12-16, rearward of trigger guard 31 is the mid-stock section 11 including mid-stock web walls 32r, 321, upper mid-stock wall 32a and mid-stock base wall 32b. Mid-stock wall recess pairs 33r, 331 and 35r and 351 carry configured panel inserts 36r and 361. Referring further to FIGS. 12 and 14, butt stock section 12 is formed with a molded central vertical web 14s with lower base piece 38 and upper hollow cylindrical curved piece 14c. Curved piece 14s has cylindrical hollow 41 (see FIGS. 3 and 14).
In FIGS. 15-18, mid-stock panels 36r, 361 are configured to be positioned in panel-receiving border portions 44. Border portions 44 includes planar seating surfaces 46r, 461, 47r, 471 which intersect at and define periphery lines 48r, 481. Fastener assembly 49 includes bolt 51 and nut 52 (FIGS. 13 and 15) for urging panels 36r, 361 against seating border portions 46r, 461 to strengthen the framework. Also shown are bridge plate pieces 39r and 391. Mid-stock section 11 has opening 40 (see FIG. 18).
Turning to FIGS. 19-24, an alternative embodiment of the invention is shown in which the forearm and mid-stock insert panels differ in shape and in fastening arrangement. Forearm panels 50r, 501 are secured with two (2) fastener assemblies 55, 56 and the forward end of the firearm stock sectin 10' carries a barrel-supporting piece 57'. In FIG. 22, butt stock right wall 61r, butt stock left wall 611, upper wall 61a and base wall 61b form a hollow chamber 63 in butt stock 12' which chamber 63 extends from top to bottom. A butt cushion piece 65 covers the end of butt stock section 12' cushion piece 65 covers the end of butt stock section 12' (FIG. 21). Right and left butt panels 58r, 581 are mounted in right and left panel-receiving recessed border portions 67r, 671. Each border portion 67r, 671 includes seating surfaces 68r, 681 and 70r, 701 intersecting along periphery lines 71r, 711. In FIGS. 20, 23, and 24, forearm panels 50r, 501 are shown in forearm panel-receiving border portions 74r, 741. Forward fastener assembly 55, including headed bolt 76 and threaded nut 77, are nested in panel recesses 78, 80 to provide a flush appearance. Barrel 82 rests on barrel-supporting piece 57, (FIG. 24).
Referring to FIGS. 25-29, a further embodiment shows a structural forearm central web wall 83 and upper saddle wall 84 and base wall 86. Forward nose section 88 of forearm stock section 10" includes nose wall opening 89 to accommodate rifle parts (not shown). The forward portion of stock nose saddle wall portion 84 supports barrel 91 (FIG. 29). Also shown are forearm panels 92r, 921 positioned in border areas 93r, 931 and urged against frame web structure 13" by fastener assembly 94.
FIGS. 30 and 31 illustrate in perspective another embodiment in which forearm panel seating surfaces 100r, 1001 (not shown) are parallel to the plane of forearm panel inserts 101r and 1011. Panels 101r, 1011 abut frame pieces 103r and 1031 and abut frame border areas 105r and 1051 as urged by fastener assembly 104. Mid-stock panels 102r, 1021 are similarly constructed with generally perpendicular edges 106r, 1061. Panels 102r, 1021 abut border areas 110r and 1001. Cap 113 is also shown.
Turning next to FIGS. 32-35, a further embodiment shows U-shaped butt insert cheek panel 108 secured to butt stock web section 109 using fastener 107 (FIG. 33). Stock section 109 has recess 110 between hollow forward butt portion 111 and hollow rearward butt portion 112. Also shown are midstock insert panel 114 and butt stock end portion 116.
Finally, turning to FIGS. 36--39, a modified cheek panel embodiment is shown in which the butt stock recess 117 between forward butt portion 118 and rearward butt portion 120 carries wooden panel cheek insert 121. Wood has a "warmer" feel than synthetic materials and therefore serves as a desirable cheek panel. Butt portions 118, 120 form upper and lower inner butt chambers 118a, 118b and 120a, 120b. Also shown are fastener 122, mid-stock panel 123, butt end plate 124 and butt end plate screws 126, 127. | A rifle stock having its forearm, mid-stock and butt section comprised of a one piece plastic structural framework together with attached insert panels. The plastic framework is a lightweight readily moldable structure consisting of web walls having thicknesses, spacing and openings to facilitate such fabrication. Alternatively, the framework can be made of two or more framework elements fastened together.
The framework has border recess areas for receiving panels of wood or other materials which panels are configured to fit into the recess areas and to be fastened to or urged against the framework recesses to strengthen the rifle stock and provide a more secure feel and pleasing appearance. | 5 |
This application is a National Stage Application of PCT/US2008/062202, filed May 1, 2008, in the name of Vermeer Manufacturing Company, a U.S. national corporation, applicant for the designation of all countries except the US, and John T. Bouwers and Justin J. Humpal, citizens of the U.S., applicants for the designation of the US only, and claims priority to U.S. Provisional Patent Application Ser. No. 60/928,861, filed May 10, 2007, and which applications are incorporated herein by reference. To the extent appropriate, a claim of priority is made to each of the above disclosed applications.
FIELD OF THE INVENTION
The present invention relates generally to a belt tensioning apparatus.
BACKGROUND OF THE INVENTION
Belt tension systems are found in many different types of machinery including, for example, chippers and grinders. Chippers are used to reduce branches, trees, brush, and other bulk wood products into small chips. A chipper typically includes a feed system for controlling the feed rate of wood products into the chipper, a chipping mechanism, a drive system for powering the feed system and the chipping mechanism, and a discharge chute.
The chipping mechanism is commonly a large drum that includes blades thereon which is driven by a belt. The belt rotates the drum, enabling the drum to grind, flail, cut, or otherwise reduce the material fed into the chipper into small chips. The proper tension in the belt between the motor and the drum can be difficult to maintain as the belts tend to stretch and contract over time or even during use. Accordingly, there is a need in the art for an improved belt tension system.
Accelerating chipper drums and other cutting tools from a stopped position to maximum speed can be a challenge because the drums and other cutting/grinding tools are relatively large and heavy. If the belt is fully engaged between the output shaft and the drum during start up, the engine can be overloaded. To avoid overloading the engine in the start up process, typically a clutch is used to interface between the engine and the wheel that drives the belt. The clutch typically mounts adjacent the output shaft of the engine which is typically perpendicular to the length of the chipper or grinder frame. Accordingly, the inclusion of the clutch constrains how narrow the machine can be constructed. Also, since the clutch mechanism is lighter than the engine, the inclusion of the clutch typically undesirably shifts the center of gravity of the machine off to one side of the frame. A belt tension arrangement that could eliminate the need for a clutch is desirable.
SUMMARY OF THE INVENTION
The present disclosure relates to a belt tensioning system that is configured to more effectively maintain the proper tension in the belt that is driven by the motor to drive a cutting/grinding tool. The system of the present disclosure is configured so that the tension in the belt can be maintained even if the belt stretches or contracts. The present disclosure also relates to a belt tension system and method of starting the drum rotating that eliminates the need for a clutch.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a chipper according to the principles of the present invention with portions of the engine and drum housing removed;
FIG. 2 is a side view of the drum, engine, and belt tension system of FIG. 1 .
FIG. 3 a is a cross-sectional view of a portion of torsion bar in an unloaded position;
FIG. 3 b is a cross-sectional view of a portion of torsion bar in a loaded position;
FIG. 4 is a side view of an alternative embodiment of the belt tension system of FIG. 1 ; and
FIG. 5 is a top view of the embodiment of the belt tension system of FIG. 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 the tensioning assembly 40 is shown on a chipper. In the depicted embodiment the chipper 10 is mounted to a frame 12 (chassis) that rests on wheels 14 , which enable the chipper 10 to be conveniently moved. The depicted chipper 10 includes a feed chute 16 , which is also commonly referred to as a feed table. The feed chute 16 can be any structure located at the rear of the chipper 10 that facilitates the loading of materials to be chipped into the chipper 10 . (The material to be chipped can be any material that the user desires to reduce to chips. The material is most commonly brush and tree parts, therefore, for convenience the material to be chipped will be referred to herein interchangeably as wood, trees, or brush.) In the depicted embodiment the feed chute includes a flat table portion 24 and two side walls 26 , 28 . It should be appreciated that many other configurations of the feed chute 16 are possible. Feed chutes are described in greater detail in a related application filed on May 10, 2007 titled WOOD CHIPPER INFEED CHUTE, which is incorporated herein by reference (No. 60/928,937).
The chipper 10 in the depicted embodiment includes an feed system 18 that grabs and pulls brush from the feed chute 16 into the body portion 20 of the chipper 10 which houses cutters 80 (see FIG. 2 ) that cut the brush into small chips. The cutter 80 shown has blades 82 mounted on a drum 81 . However, it should be appreciated that the cutter can be any structure that is capable of breaking the material to be chipped into chips. Once the material is broken into small chips, the chips are then projected out of the chipper 10 through a discharge chute 22 . Feed rollers are described in greater detail in a related application filed on May 10, 2007 titled SYSTEM FOR CONTROLLING THE POSITION OF A FEED ROLLER, which is incorporated herein by reference (No. 60/928,926). The cutter drums are described in greater detail in a related application filed on May 10, 2007 titled CHIPPER DRUM WITH INTEGRAL BLOWER which is incorporated herein by reference (No. 60/928,928). In the depicted embodiment the longitudinal axis 11 of the chipper 10 is parallel to the general direction that material to be chipped flows through the chipper 10 .
Referring to FIG. 2 , a belt tension assembly 40 is shown. In the depicted embodiment the belt tension assembly 40 includes a belt 42 that extends around a first wheel 87 that is fixed to an end of the drum 81 such that by rotating the wheel 87 the drum 81 rotates. The belt 42 also extends around second wheel 83 attached to the output shaft 84 of the engine 85 . A tensioning wheel 90 presses against the inside of the belt to apply tension to the belt 42 to enable it to frictionally engage the first wheel 87 and the second wheel 83 .
The tension wheel 90 is mounted to an arm 92 . The arm 92 is connected to a frame 94 that pivots relative to engine 85 . The frame 94 pivots when the cylinder 96 is extended and retracted. To apply tension to the belt 42 the cylinder 96 is extended. To release the tension in the belt 42 , the cylinder 96 is retracted. In the depicted embodiment, the arm 92 is connected to the frame by a torsion spring member 98 . The torsion spring member 98 biases the tension wheel 90 outwardly (upwardly towards the belt) which applies tension to the belt 42 . In use the cylinder 96 is extended to engage the belt 42 and preload the torsion spring member 98 . In the depicted embodiment, the preloading occurs when the frame 94 is pivoted clockwise and the arm 92 is pivoted counterclockwise as a result of the extension of the cylinder 96 . If the belt 42 stretches during operation, the cylinder 96 need not be extended further to compensate because the torsion spring member 98 will bias the tension wheel 90 against the belt 42 . The torsion spring member 98 keeps a relatively constant tension force on the belt 42 to dampen the motion of the belt 42 .
Referring to FIGS. 3 a and 3 b , the torsion spring member (torsion bar) 98 in the depicted embodiment operates according to the rubber torsion spring principle. Four rubber inserts 100 are located in the corners of a square tube 102 and a smaller square tube 104 is located therein. From the neutral position shown in FIG. 3 a the square tube 104 is designed to rotate in either the clockwise or counterclockwise direction as shown in FIG. 3 b . When the square tube 104 rotates, the rubber inserts 100 deform. In the depicted embodiment the larger square tube 102 is mounted to the frame 94 which pivots, and the smaller square tube is mounted to the arm 92 .
The above arrangement provides a way for applying tension to a belt 42 while the belt 42 stretches or contracts, without having to adjust the extension of the cylinder 96 . The belt tension system 40 above also enables the belt 42 to be smoothly and continuously engaged and disengaged. In the depicted embodiment, there is no clutch positioned between the output shaft 84 and the wheel 83 that drives the belt 42 . To bring the drum 81 up to operating speed from a stopped position, the cylinder 90 can be selectively extended and retracted to cause the belt 42 to grab and release for short periods of time. This pulsing engagement of the belt 42 can be use to gradually increase the rotational speed of the cutter 80 to avoid overloading the engine 85 .
Referring to FIGS. 4 and 5 an alternative embodiment of the belt tension system is shown. Similar to the first embodiment, the belt tension assembly 40 ′ of the second embodiment includes a belt 42 ′ that extends around a first wheel 87 ′ that is fixed to an end of the drum (e.g., the drum 81 of the first embodiment) such that by rotating the wheel 87 ′ the drum rotates. The belt 42 ′ also extends around second wheel 83 ′ attached to the output shaft 84 ′ of the engine 85 . In the second embodiment the tensioning wheel 90 ′ presses against the outside rather than the inside of the belt 42 ′ to apply tension to the belt 42 ′. Also, instead of using a cylinder 96 to apply the pressure a lever 110 is used to manually apply the tension to the belt 42 ′.
In the depicted embodiment, the tension wheel 90 ′ is mounted to an arm 92 ′. The arm 92 ′ is pivotally connected to a frame 94 ′ at pivot 114 . To apply tension to the belt 42 ′ the lever 110 is raised. To release the tension in the belt 42 ′, the lever 110 is lowered. A coil spring 112 is used instead of the torsion spring member 98 of the first embodiment to maintain tension in the belt 42 ′ as the belt stretches. Though in the depicted embodiment the lever 110 is generally straight and arranged horizontally, it should be appreciated that it can be arranged in other orientations as well and can be of other geometric configurations. For example, the lever 110 could be L-shaped and/or arranged vertically. In the depicted embodiment the lever 110 is generally parallel the side of the frame 94 ′ and perpendicular to the output shaft 84 ′. In some embodiment the lever 110 is positioned at an angle relative to the side of the frame 94 ′. The lever 110 could be, for example, within +/−30 degrees from being parallel to the frame 94 ′ (i.e., 30 degrees from being perpendicular to the output shaft 84 ′). It should be appreciated that features from the first embodiment can be combined with features from the second embodiment. For example, the spring 112 could be used with the cylinder 96 instead of with the lever 110 .
Referring to FIG. 5 , the distance L 1 from the inside edge of the second wheel 83 to the flywheel mounting plate 116 is relatively small. For example, the distance L 1 on a prior art type machine that includes a clutch and an engine horsepower of 185 is typically about 16 inches. Utilizing the principles described above, the distance L 1 for a chipper with an engine horsepower rating anywhere between 185 HP and 330 HP can be decreased to eight inches or less. In the depicted embodiment, the chipper includes a 215 HP engine and the distance L 1 is only about six inches. Both embodiments depicted show a bearing supported stub shaft as the drive coupler to the engine, however, it should be appreciated that many other configurations are also possible. For example, an engine drive direct coupled shaft that has both an inboard and an outboard bearing could also be used.
The above arrangement provides a way for applying tension to a belt 42 ′ while the belt 42 ′ stretches or contracts without having to readjust the position of the lever 110 . The belt tension system 40 ′ above also enables the belt 42 ′ to be smoothly and continuously engaged and disengaged. In the depicted embodiment, there is no clutch positioned between the output shaft 84 ′ and the wheel 83 ′ that drives the belt 42 ′. To bring the drum up to operating speed from a stopped position, the lever 110 can be selectively raised and lowered to cause the belt 42 ′ to grab and release for short periods of time. This pulsing engagement of the belt 42 ′ can be use to gradually increase the rotational speed of the cutter to avoid overloading the engine. Alternatively, the lever 110 can be gradually raised causing the belt 42 ′ to transition from slipping to gripping over a longer period of time to allow the drum to gradually increase its speed.
In both depicted embodiments the engine can be mounted along the longitudinal axis of the chipper 10 so that the weight on the wheels of the chipper on the left and right sides is balanced. In the depicted embodiments the weight on the wheels on either side is within (70-30) percent and more preferably within (60-40) percent. The absence of a clutch, which is typically mounted near the output shaft of the engine, enables the weight of the engine to be distributed closer to the center of the chipper.
It should be appreciated that the belt tension systems of the invention can be used in other types of machinery as well. The use of the belt tension system in a chipper is only one potential environment for the system. The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended. | A belt tensioning system configured to more effectively maintain the proper tension in a belt that can be engaged and disengaged. Proper tension in the belt is maintained even if the belt stretches or contracts by including a spring biased member between a tension wheel and a pivot frame. The spring member is preloaded such that when the belt stretches the tension wheel is biased against the belt by the force of the spring. Also, by selectively engaging the tension system one can avoid overloading the engine without the need to incorporate a clutch. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application claims priority under 35 USC §119 to International Patent Application No. PCT/IB03/01443 filed on Apr. 17, 2003.
TECHNICAL FIELD
The invention relates to a method for negotiation or re-negotiation of a parameter or parameters for use in the operation of a protocol that controls data transmission between first Communication Units (CUs) and third CUs via second CUs, where the protocol is operated by protocol entities in the first and third CUs, where a first CU is always associated with a second CU at a time, where a second CU is always associated with a third CU at a time, and where there exist second CUs of at least a first and second type and/or third CUs of at least a first and second type that require different choices of said parameter.
BACKGROUND OF THE INVENTION
In mobile radio systems of the second and third generation, such as the Global System for Mobile Communications (GSM) and the Universal Mobile Telecommunications System (UMTS), Non-Transparent (NT) data bearers are provided that offer an error-free data transfer service to the user. The data transfer service is based on the Radio Link Protocol (RLP) and the Layer-2 Relay (L2R) Character Oriented Protocol (COP). The RLP function offers an Automatic Repeat Request (ARQ) protocol that extends from the mobile station (MS) to the network Interworking Functions (IWF) in the Mobile-services Switching Centre (MSC) in order to detect errors by means of a Forward Error Correction (FEC) procedure and RLP's Frame Check Sequence (FCS) for each transmitted RLP frame, where an RLP frame represents an RLP Protocol Data Unit (PDU), and to eliminate errors by repeating the transmission of the frame under exploitation of the time-variance of the transmission medium. The L2R function converts the layer-2 protocol of the MS into a COP that uses transmission protected by an RLP.
The RLP is controlled by several parameters such as acknowledgement, reply and re-sequencing timers or the number of retransmission attempts or required window sizes, that either are assigned default values or can be modified by the user or network e.g. by means of AT commands. If a change of parameters is initiated in either the MS RLP entity or the MSC RLP entity, the desired parameters are signalled to the corresponding peer RLP entity via exchange IDentification (XID) frames, which are RLP frames (PDUs) in which the information field is interpreted as exchange identification instead of data. To start negotiation, an XID command frame will be signalled. The peer entity confirms the value of each parameter by returning the value within an XID response or offering lower or higher values of the parameter in its place depending on the sense of negotiation of the parameter.
The RLP may use one physical link (single-link) or from 1 up to 4 sub-streams on one or more physical links (multi-link). The multi-link version of the RLP protocol is only applicable in GSM and not in UMTS.
Among said control parameters of the RLP protocol, the acknowledgement timer T1 associated with the transmitting RLP entity indicates the re-transmission period after which the re-transmission of a not-acknowledged frame may be started. Due to ARQ in combination with FEC, each received RLP frame is checked for correct/incorrect reception at the receiving RLP entity, and correct/incorrect reception is signalled back to the transmitting peer RLP entity. The timer T1 defines the maximum time period starting with the transmission of an RLP frame within which a correct/incorrect acknowledgement of the transmitted RLP frame is expected. An expiration of the timer T1 causes the retransmission of the frame because the acknowledgement of the sent frame was not received in time.
Among said control parameters of the RLP protocol, the timer T2 associated with the receiver indicates the maximum permissible period the receiving RLP peer entity is allowed between the reception of a frame and the transmission of the acknowledgement message.
Among said control parameters of the RLP protocol, the re-sequencing timer T4 guards the maximum difference between the delays of frames transmitted on different physical links within the multi-link RLP protocol. The timer T4 defines how great the variation of the transmission delay of all physical links can be. If received frames are out of sequence, the receiver waits for the duration of timer T4 for the missing frames before starting any recovery actions. Concluding, in multi-link operation (e.g. GSM), T1>T2+T4+2*TD has to hold, were TD is the transmission delay between MS and MSC, whereas in single-link transmission (e.g. UMTS), T1>T2+2*TD has to hold.
In both GSM and UMTS, the transmission of the PDUs/frames of the RLP is performed by lower layers of the protocol stack. The delay characteristics of the RLP frames are thus at least dependent on the delay characteristics of the physical layer, i.e. the lowest layer in the protocol stack. When considering the transmission of RLP PDUs from an MS RLP entity to an MSC RLP entity in GSM, in the physical layer the transmission paths between the MS and the Base Transceiver Station (BTS), between the BTS and the Base Station Controller (BSC) and between the BSC and the MSC have to be taken into account. In UMTS, basically the same propagation paths are encountered, where the MS corresponds to the User Equipment (UE), the BTS corresponds to the Node B and the BSC corresponds to the Radio Network Controller (RNC). In the sequel, GSM notation will be used to identify the components of both mobile radio systems.
The BTS-BSC and BSC-MSC interfaces are usually realised by lower-delay connections such as Time Division Multiplex (TDM) connections (e.g. ISDN primary rate). However, also higher-delay connections such as Internet Protocol (IP), e.g. in a Distributed Radio Access Network (DRAN) environment or in an IP-based GSM Intranet Office (GIO) environment, or satellite connections may be applicable. It is easily understood that depending on the delay characteristics of the BTS-BSC or BSC-MSC connection, especially the timers T1 and T4 of the RLP have to be adapted accordingly to assure proper operation of the mobile radio system.
The applicant's international patent application WO 02/25888 A2 discloses one approach for an adaptation of RLP timers. WO 02/25888 A2 sets out from the fact that, in a typical GSM physical link, the transmission delay is within a tightly bounded range so that the RLP entities will use default values for the RLP timers based on the expected characteristics of the physical link. For the case when unexpectedly large delays occur, e.g. in an IP-based GSM office environment, an XID proxy unit is proposed as an additional negotiation unit that monitors and verifies XID commands sent between the MS and MSC entities. The XID proxy has knowledge of the maximum delay values for the physical link between the MS and the MSC. Based on this information, it has the capacity to intervene in the process of negotiation of T1 timer values between the MS and the MSC with the aim of ensuring that the value that is settled upon is large enough to cope with transmission delays that might be beyond the expectations (the default or offered timer values) of the MS and MSC.
In this prior art approach, the XID proxy is only activated when it “sniffs” the passing of an XID negotiation message between the RLP entities of the MS and the MSC. For this to happen, it is required that a new NT data call is set up within the higher-delay network, so that standard RLP timer negotiation between the RLP entities of MS and MSC is initiated via XID frames.
However, the prior art approach fails to adapt the RLP parameters to the delay characteristics of a higher-delay network if the NT data call was set up—and thus parameterised with a smaller timer during the initial RLP timer negotiation—in a lower-delay network and is subsequently handed over to the higher delay network, where no re-negotiation of the RLP timers takes place and thus the XID proxy is not activated. Such a situation occurs if a MS is associated with a first BTS that is connected to its MSC via TDM, and then is handed over to a BTS that is connected to its MSC via IP (where both MSCs can well be the same).
A similar problem arises when a hand-over of a UMTS-based NT data call to a GSM-based call occurs and RLP parameters that are essential in the GSM system, but not essential in the UMTS system, e.g. the RLP timer T4, are not negotiated or re-negotiated upon entry in the GSM system, so that default values are used in the GSM system instead of using values that have been adapted or selected for particular use in the GSM system.
SUMMARY OF THE INVENTION
In view of the above-mentioned problems, it is thus the object of the present invention to provide a method for improved protocol parameter adaptation for certain types of non-transparent data call handovers.
To solve the object of the invention, it is proposed that a method for negotiation or re-negotiation of a parameter for use in the operation of a protocol that controls data transmission between first Communication Units (CUs) and third CUs via second CUs, where the protocol is operated by protocol entities in the first and third CUs, where a first CU is always associated with a second CU at a time, where a second CU is always associated with a third CU at a time, and where there exist second CUs of at least a first and second type and/or third CUs of at least a first and second type that require different choices of said parameter, is characterised in that when an existing association of said first CU with a former second CU is changed to an association of said first CU with a new second CU, said protocol entities of the first CU and said protocol entities of the third CU associated with the new second CU exchange at least one negotiation message containing a value for said parameter. Thus when the association of the first CU to the second CU is changed, either resulting in an exchange of the type of the second CU in the chain first-second-third CU from a former second CU of a first type to a new second CU of a second type when both the former and new second CU are associated with the same third CU (of any type), or resulting in an exchange of the type of the third CU in the chain first-second-third CU when the former second CU and the new second CU are of the same type, but associated with different third CUs of a first and second type, respectively, or resulting in an exchange of the types of both the second and the third CU in the chain first-second-third CU, when the former and new second CUs of the first and second type are associated with different third CUs of a first and second type, or resulting in no exchange of the types of the second and third CUs in the chain first-second-third CU, when the former second CU is of the same type as the new second CU and if both second CUs are associated with the same type of third CU, either the protocol entity of the first or third CU are informed of the change of associations and are triggered to transmit a negotiation message to their corresponding peer entity. The negotiation message represents a proposal to change a parameter, which affects the performance of the protocol controlling the data transmission between the first and third CU via the second CU and which depends on the type of second and/or third CU used in the chain first-second-third CU. The influence of the parameter on the protocol may as well be seen in the fact that the parameter is not required, when a third CU of the first type is part of the chain first-second-third CU, but is required when the third CU of the first type is replaced by a third CU of the second type.
A first preferred embodiment of the invention is characterised in that the former second CU was associated with a third CU of a first type and the new second CU is associated with a third CU of a second type. The type of the third CU in the chain first-second-third CU thus changes from a first type to a second type. In said event of a change of the third CU from a first type to a second type, an additional change of the type of the second CU from a first type to a second type may occur or not.
According to the first preferred embodiment of the invention, it is preferred that in said exchange of at least one negotiation message, the protocol entity in the first CU performs the following steps: a first step of checking whether said parameter is required for the operation of said protocol between the protocol entities of the first CU and the third CU that is associated to the new second CU, a second step of checking whether a value for said parameter needs to be negotiated or re-negotiated, and a third step of transmitting a negotiation message containing a value for said parameter to the protocol entity of the third CU associated with the new second CU, if said first and second checking steps produced positive results. The parameter is thus only negotiated or re-negotiated within the protocol if it is required for the operation of said protocol between the protocol entities of the first CU and the third CU that is associated to the new second CU, a fact that may mainly depends on the type of third CU. Elsewhere, both protocol entities in the first and third CU use a default value for the parameter, and negotiation or re-negotiation is not necessary but may still be carried out. The initiative for parameter negotiation or re-negotiation can as well be started by the protocol entity of the third CU. Then, however, no values for the parameter as selected by the user can serve as a basis for starting the parameter negotiation/re-negotiation.
In said exchange of at least one negotiation message in the first embodiment of the invention, the protocol entity of the third CU associated with the new second CU performs the following steps: receiving the negotiation message transmitted by the protocol entity of the first CU containing a value for said parameter, and transmitting a negotiation message to the protocol entity of the first CU containing the received or a higher value for said parameter.
The first embodiment of the present invention is advantageously characterised in that said first CU is a Mobile Station (MS) of a mobile radio system, that said second CUs are Base Transceiver Stations (BTSs), and that said third CUs are Mobile-services Switching Centres (MSCs). The invention thus is for instance applicable to GSM systems and UMTS systems. In the MSCs, the protocol entities are operated by the Interworking Function (IWF).
In the physical link between BTS and MSC, furthermore a Base Station Controller (BSC) may be provided.
According to the first embodiment of the present invention, it is further preferred that said third CU of the first type is a MSC of a mobile network operated according to the UMTS standard or a derivative thereof (UMTS-MSC), and that said third CU of the second type is a MSC of a mobile network operated according to the GSM standard or a derivative thereof (GSM-MSC). With the change of an association of the MS with a former BTS that is associated with a UMTS-MSC, to an association of the MS to a new BTS that is associated with a GSM-MSC, a handover of the MS from a UMTS system to a GSM system occurs, and a negotiation or re-negotiation of parameters, which are not required for said protocol when running in the UMTS system, may be necessary to properly operate the protocol in the GSM system.
According to the first embodiment of the invention, it is preferred that said protocol is a circuit switched, non-transparent single- and/or multi-link data protocol with Automatic Repeat Request (ARQ).
According to the first embodiment of the invention, it is further preferred that said protocol is the Radio Link Protocol (RLP). Within the RLP protocol, exchange IDentification (XID) messages then can be used as negotiation messages.
Said parameter then preferably defines the value of a re-sequencing timer that guards the difference between the delays of frames transmitted on different physical links within a multi-link protocol.
Said first step of checking whether said parameter is required for the operation of said protocol between the protocol entities of the first CU and the third CU that is associated to the new second CU then comprises the step of checking whether the data transmission between the MS and the GSM-MSC is a multi-link transmission or whether there is a possibility that the single-link transmission will be upgraded to a multi-link transmission later. In single-link transmission, the re-sequencing timer is purposeless (zero) and thus does not have to be re-negotiated upon entry of the MS into the GSM cell.
Said second step of checking whether said parameter needs to be negotiated or re-negotiated comprises the step of checking whether a value for said re-sequencing timer was defined by the user of the MS.
If no value was defined by the user, default values for the re-sequencing timer as stored in the RLP entities of both the MS and GSM-MSC may be used, and no negotiation or re-negotiation was necessary.
A second preferred embodiment of the invention is characterised in that the former second CU is a second CU of a first type and the new second CU is a second CU of a second type. Thus when an association of the first CU with a former second CU changes to an association of the first CU with a new second CU, the type of the second CU in the chain first-second-third CU changes from a second CU of a first type to a second CU of a second type. Note that, depending on the association of the second CUs with their third CUs, an additional change of the type of the third CU from a first type to a second type may occur as well.
In said exchange of at least one negotiation message in the second embodiment of the invention, the protocol entity of the third CU associated with the new second CU performs the step of transmitting a negotiation message containing a value for said parameter to the protocol entity of the first CU. However, the initiation of the parameter re-negotiation may as well be started by the protocol entity of the first CU.
According to the second embodiment of the invention, it is preferred that said value for said parameter depends on the transmission characteristic of the transmission medium between the new second CU and its associated third CU and that said value can be determined by said third CU for each of the second CUs it can be associated with. This can either be achieved by measurements of the transmission characteristics that are initiated by the third CU or by a look-up table that is stored at the third CU and contains the values for each possible association of the third CU with second CUs, where the transmission characteristic of the medium between second and third CU also contains the influence of the BSC.
In said exchange of at least one negotiation message in the second embodiment, the protocol entity of the first CU preferably performs the following steps: receiving the negotiation message transmitted by the protocol entity of the third CU that is associated with the new second CU and containing a value for said parameter, and transmitting a negotiation message to the protocol entity of the third CU that is associated with the new second CU containing the same or a higher value for said parameter. Thus the value for said parameter is up-negotiated based upon a value for said parameter that is proposed by the third CU.
According to the second embodiment of the invention, it is preferred that said first CU is a Mobile Station (MS) of a mobile radio system, that said second CUs are Base Transceiver Stations (BTSs), and that said third CUs are Mobile-services Switching Centres (MSCs). The invention thus is for instance applicable to GSM systems and UMTS systems. In the MSCs, the protocol entities are operated by the Interworking Function (IWF). In the physical link between BTS and MSC, furthermore a Base Station Controller (BSC) may be provided.
According to the second embodiment of the invention, it is further preferred that one out of the first and second types of said second CU is a BTS that is connected to its associated MSC via a lower-delay network, and that the other type of said second CU is a BTS that is connected to its associated MSC via a higher-delay network. The method according to the second embodiment of the present invention aims at the re-negotiation of a parameter, which influences the performance of the protocol controlling the data transmission between MS and MSC and which is affected by a change from a BTS and related network with a lower delay to a BTS and related network with a higher delay or vice versa from a BTS and related network with a higher delay to a BTS and related network with a lower delay.
Said lower-delay network may be a Time Division Multiplex (TDM) network.
Said higher-delay network may be at least partially based on the Internet Protocol (IP) or a satellite connection. E.g. the connection between BTS and BSC may be IP-based, and the connection from the BSC to the MSC may be TDM-based.
According to the second embodiment of the invention, the MSC that is connected to its associated BTS via the lower-delay network may either be operated according to the UMTS standard, the GSM standard or a derivative thereof, and the MSC that is connected to its associated BTS via the higher-delay network may either be operated according to the UMTS standard, the GSM standard or a derivative thereof.
According to the second embodiment of the invention, it is preferred that said protocol is a circuit switched, non-transparent single- and/or multi-link data protocol with Automatic Repeat Request (ARQ).
According to the second embodiment of the invention, it is further preferred that said protocol is the Radio Link Protocol (RLP). Within the RLP protocol, exchange IDentification (XID) messages then can be used as negotiation messages.
Said parameter advantageously defines the value of an acknowledgement timer that guards the re-transmission period after which the re-transmission of a not-acknowledged frame within a protocol with ARQ may be started. This parameter extremely depends on the delay characteristics of the physical link between MS and MSC, which incorporates the link between BTS and BSC and BSC and MSC.
Said parameter further advantageously defines the value of a re-sequencing timer that guards the difference between the delays of frames transmitted on different physical links within a multi-link protocol. If the handover takes place within the GSM system or from the UMTS system into the GSM system, multi-link data transmission or single-link data transmission that may later be upgraded to multi-link transmission, e.g. within the RLP protocol, is possible, and a re-sequencing timer is required. As the acknowledgement timer, the re-sequencing timer extremely depends on the delay characteristics of the physical link between MS and MSC, which incorporates the link between new BTS and BSC and BSC and MSC.
Said transmission characteristic is preferably related to the transmission delay. The MSC then administrates a look-up table that contains the delays (or maximum delay difference in case of multi-link transmission) for each BTS that it may become associated with, and in case of a change of a lower-delay BTS to a higher-delay BTS or vice versa in the chain MS-BTS-(BSC)-MSC proposes a suited value for said acknowledgement or re-sequencing timer to the MS, where said value is taken from that look-up table.
The object of the invention is further solved by a method for negotiation of a parameter or parameters for use in the operation of a protocol that controls data transmission between first Communication Units (CUs) and third CUs via second CUs, where the protocol is operated by protocol entities in the first and third CUs, where a first CU is always associated with a second CU at a time, where a second CU is always associated with a third CU at a time, and where there exist second CUs of at least a first and second type and/or third CUs of at least a first and second type that require different choices of said parameter, which is characterised in that in the case that it is possible that an association of said first CU with a second CU that is associated with a third CU of a first type may be changed to an association of said first CU with a second CU that is associated with a third CU of a second type, said protocol entities of said first CU and said protocol entities of said third CU of the first type perform the step of exchanging at least one negotiation message containing a value for said parameter prior to said change of associations.
In the following, this solution will be referred to as the third embodiment of the present invention. If it is possible that a change of the third CU in the chain first-second-third CU occurs from a third CU of a first type to a third CU of a second type, wherein in the former case, the parameter is not required for said protocol, but in the latter case, said parameter is required for said protocol, it makes sense to negotiate said parameter between the protocol entities of the first CU and the protocol entities of the third CU of the first type, i.e. before the change of associations occurs. Parameter negotiation may be initiated by either the first of third CU by proposing a value for said parameter. The negotiated value for said parameter is then stored in the protocol entities of the first CU and the third CU of the first type, but is not used in the operation of said protocol. When the third CU of the first type in the chain first-second-third CU is changed to a third CU of a second type, said value for the parameter is handed from the third CU of the first type to the third CU of the second type, unless the third CU of the first type and the third CU of the second type have a common part, e.g. an interworking function for the case that the third CUs are MSCs of mobile networks operated according to different standards such as UMTS and GSM, wherein said common part maintains the association with the first CU and holds said value for the parameter during the change of the third CU in the chain first-second-third CU. Thus parameter re-negotiation between the first CU and the third CU of the second type after the change of associations is not necessary, because the required value for the parameter is already available in both protocol entities.
According to the third embodiment of the present invention, it is advantageous that in said exchange of at least one negotiation message, the protocol entities in the first CU or the third CU of the first type perform the following steps: checking whether it is possible that said data transmission between the first CU and the third CU of the second type is a multi-link data transmission that requires the definition of a re-sequencing timer as said parameter for said protocol, and checking whether a value for said re-sequencing timer is available as a basis for negotiation.
For example, when the first CU is a MS of a mobile radio system, the second CUs are BTSs and the third CUs are MSCs of a mobile network operated according to the UMTS standard (third CU of the first type) and GSM standard (third CU of the second type), parameter negotiation then only takes place if the future call in the GSM system is possibly a multi-link call, because otherwise the re-sequencing timer would not be required. As a basis for parameter negotiation, a value for the parameter as selected by the user of the MS or default values as stored in the UMTS-MSC or the MS may be used.
The object of the invention is further solved by a computer program product directly loadable into the internal memory of a digital computer, comprising software code portions for performing the steps as performed by the protocol entities of the first and third CUs when said product is run on a computer.
The object of the invention is further solved by a system for data transmission between first Communication Units (CUs) of said system and third CUs of said system via second CUs of said system, where the protocol that controls said data transmission is operated by protocol entities in the first and third CUs, where a first CU is always associated with a second CU at a time, where a second CU is always associated with a third CU at a time, and where there exist second CUs of at least a first and second type and/or third CUs of at least a first and second type that require different choices of at least one parameter for use in the operation of said protocol, which is characterised in that when an existing association of said first CU with a former second CU is changed to an association of said first CU with a new second CU, said protocol entities of the first CU and protocol entities of the third CU associated with the new second CU exchange at least one negotiation message containing a value for said parameter.
The object of the invention is further solved by a system for data transmission between first Communication Units (CUs) of said system and third CUs of said system via second CUs of said system, where the protocol that controls said data transmission is operated by protocol entities in the first and third CUs, where a first CU is always associated with a second CU at a time, where a second CU is always associated with a third CU at a time, and where there exist second CUs of at least a first and second type and/or third CUs of at least a first and second type that require different choices of at least one parameter for use in the operation of said protocol, which is characterised in that in the case that it is possible that an association of said first CU with a second CU that is associated with a third CU of a first type may be changed to an association of said first CU with a second CU that is associated with a third CU of a second type, said protocol entities of said first CU and said protocol entities of said third CU of the first type perform the step of exchanging at least one negotiation message containing a value for said parameter prior to said change of associations.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. In the figures show:
FIG. 1 an example scenario for the application of the first and third embodiment of the present invention,
FIG. 2 a signalling chart according to the example of the first embodiment of the present invention according to FIG. 1 ,
FIG. 3 an example scenario for the application of the second embodiment of the present invention, showing an Internet Protocol (IP) based connection or a satellite based connection.
FIG. 4 a signalling chart according to the example of the second embodiment of the present invention according to FIG. 3 , and
FIG. 5 a signalling chart according to the example of the third embodiment of the present invention according to FIG. 1 .
DETAILED DESCRIPTION
FIG. 1 depicts an example for the application of the first and third embodiment of the present invention. A user 1 that represents a MS is located in the coverage area of a UMTS cell 2 , which is associated with a UMTS-MSC, and creates an NT data call. The data call is configured via AT commands that are depicted enlarged on the display 3 of the users communication equipment. In particular, the user requests a Fixed Network User Rate (FNUR) of 56 kbps with AT command +CBST, changes the RLP parameter timer T4 to be 60 ms with AT command +CRLP and initiates the call with the command ATD<number>. Call set-up starts, and the RLP entity of the MS negotiates its connection parameters by sending an XID command frame to the peer RLP entity in the UMTS-MSC.
According to the first embodiment of the present invention, the timer T4 is not negotiated, because it is purposeless in UMTS and has therefore to be ignored. However, the timer T4 as selected by the user of the MS 1 is stored in the protocol entity of the MS 1 . The RLP entity at the UMTS-MSC confirms the parameters proposed by sending an XID response frame back to the RLP entity of the MS. After a while, the user sees a CONNECT on the screen indicating that the connection is ready for data transfer and starts data transfer.
During the data transfer, the user 1 leaves the coverage area of the UMTS cell, and the NT data call is handed to a GSM cell 4 that is associated with a GSM-MSC.
In this particular case, the resulting call in GSM is a multi-slot call, so that RLP timer T4 is required. In a prior art system, both RLP entities of the MS and the GSM-MSC would start using default values for the timer T4. In contrast, according to the first embodiment of the present invention, parameter T4 is re-negotiated between MS and GSM-MSC upon entry in the GSM cell, so that the timer T4, which was set to 60 ms by the user during call set-up in the UMTS cell, is considered within the RLP of the GSM cell.
FIG. 2 depicts a corresponding signalling chart between the RLP entities 5 in the MS and the RLP entities 6 in the MSC for the case of a system handover between UMTS and GSM, as exemplarily introduced in FIG. 1 . After call set-up in the UMTS cell, data transfer 7 is started between the RLP entities 5 and 6 based on the RLP protocol. The event of a handover of the NT data call from a UMTS-MSC to an GSM-MSC is indicated to the RLP entity 5 of the MS by means of an indication 8 . The RLP entity 5 then transmits an XID command frame 10 with the value T4 as pre-selected by the user to its peer RLP entity 6 in the GSM-MSC, which accepts or further increases the proposed value of the timer T4 by transmitting an XID response message 11 . Thus the timer T4 is re-negotiated upon entry in the GSM cell, and further data transfer 12 can start based on a multi-link transmission with re-sequencing timer T4=60 ms.
FIG. 3 depicts an example scenario for the application of the second embodiment of the present invention. A MS 13 is located in the coverage area of a first BTS 14 and sets up a NT multi-link GSM data call. BTS 14 is connected to a BSC via a TDM-based connection 16 . The BSC 15 in turn is connected to a GSM-MSC 17 via a second TDM-based connection 18 . The network between BTS 14 and GSM-MSC 17 thus is entirely TDM-based. The MS 13 then moves out of the coverage area of BTS 14 and moves into the coverage area of BTS 19 , so that an intra-MSC handover occurs. BTS 19 is connected to a BSC 20 via an IP-based connection 21 or a satellite based connection, and the BSC 20 is connected to the same MSC 17 as BSC 15 via a TDM-based connection 22 . The network between BTS 19 and GSM-MSC 17 thus is partially IP-based. Due to the IP-based connection 21 , the delay and the delay variation of the frame/PDUs transmitted within the RLP protocol is significantly higher when MS 13 is associated with BTS 19 as compared to the case when MS 13 is associated with BTS 14 . In prior art, the timers T1 and T4 are not automatically re-negotiated after such a handover, and default values for the timers T1 and T4, which are optimised for TDM-based connections between the BTS and the GSM-MSC, are adopted by the RLP entities in the MS and GSM-MSC. In contrast, according to the second embodiment of the present invention, suited values for the timers T1 and T4 are stored in the MSC and are automatically re-negotiated upon entry of the MS 13 into the cell which is operated by the partially IP-based network.
FIG. 4 depicts a corresponding signalling chart between the RLP entities 23 in the MS and the RLP entities 24 in the GSM-MSC for the case of a system handover between a lower-delay TDM-based network and a higher-delay partially IP-based network as introduced in FIG. 3 . After call set-up in the lower-delay network, data transfer 25 is started between the RLP entities 23 and 24 based on the RLP protocol. The event of a handover of the NT data call from the lower-delay network with BTS 14 to a higher-delay network with BTS 19 is indicated to the RLP entity 24 of the GSM-MSC by means of an indication 26 . The RLP entity 24 in the GSM-MSC then transmits and XID command frame 28 with the value T1 as stored in the GSM-MSC for the connection between GSM-MSC and associated BTS 19 to its peer RLP entity 23 in the MS, which accepts or further increases the proposed value of the acknowledgement timer T1 by transmitting an XID response message 29 . The same re-negotiation takes place for the re-sequencing timer T4 via XID command 30 transmitted by the RLP entity 24 in the GSM-MSC and XID response 31 transmitted by the RLP entity 23 in the MS. Both parameters can be re-negotiated also with a single XID command/response pair. Thus both timers T1 and T4 are re-negotiated upon entry in the higher-delay network, and data transfer 32 in the higher-delay network becomes possible.
FIG. 5 depicts a signalling chart between the RLP entities 33 in the MS and the RLP entities 34 in the MSC for the case of a data call handover between UMTS and GSM (cf. the scenario of FIG. 1 ) and for the case that the third embodiment of the present invention is used to adapt protocol parameters to the handover prior to the actual handover. During call set-up in the UMTS cell 2 , the parameter T4 as pre-selected by the user of the MS 1 is negotiated in view of a possible future handover to a GSM cell 4 . To this aim, the MS RLP entity 33 transmits an XID command frame 35 with the value T4 as pre-selected by the user of MS 1 (T4=60 ms) to its peer UMTS-MSC RLP entity 34 , which accepts or further increases the proposed value of the timer T4 by transmitting an XID response message 36 . The negotiated value for the parameter T4 is then stored in the RLP entities of both MS 33 and UMTS-MSC 34 , but is not used in the RLP protocol within the UMTS system. Then data transfer 37 is started between the RLP entities 33 and 34 based on the RLP protocol. After a handover 38 of the MS 1 from the UMTS cell 2 to the GSM cell 4 , data transfer 39 between the MS RLP entity 33 and the GSM-MSC RLP entity 34 starts without parameter re-negotiation. However, due to the fact that the re-sequencing timer T4 is relevant for the RLP protocol in the GSM system, the value for T4 as available in the MS RLP entity 33 and in the GSM-MSC RLP entity 34 is used in the GSM RLP protocol. The value for T4 is available in both the UMTS-MSC and the GSM-MSC RLP entities despite the fact that a handover occurred from the UMTS-MSC to the GSM-MSC, because the same interworking function (IWF) with the RLP entity that has been reserved at the setup of the call will be used throughout the entire call. I.e., even after a handover, the same IWF is still used.
The invention has been described above by means of preferred embodiments. It should be noted that there are alternative ways and variations which are obvious to a skilled person in the art and can be implemented without deviating from the scope and spirit of the appended claims, e.g. the direction of the change of the parameter values in the negotiation may be upwards or downwards depending on the meaning of the parameter being negotiated. | The invention relates to a method and a computer program product for negotiation of a parameter for a protocol that controls data transmission between first Communication Units (CUs) and third CUs via second CUs. An improved protocol parameter adaptation for certain non-transparent data call handovers is achieved by proposing that when an existing association of said first CU with a former second CU is changed to an association of said first CU with a new second CU, protocol entities of the first CU and protocol entities of the third CU associated with the new second CU exchange at least one negotiation message containing a value for said parameter. The invention further relates to a system for data transmission. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to earth-working equipment, such as an agricultural implement pulled by a tractor; and more particularly to a method for controlling a hydraulic system that operates a hitch that couples the implement to the tractor.
[0005] 2. Description of the Related Art
[0006] A variety of agricultural implements are available to be pulled by a tractor for working earth in a farm field in which crops will be or have been planted. The implement is connected to a standard three-point hitch with right and left drag links on the rear of the tractor and the hitch can be operated to raise and lower the implement. The hitch is raised and lowered hydraulically by piston-cylinder assembly that is operated by a valve that controls the flow of fluid to and from the piston-cylinder assembly.
[0007] A conventional tractor has a control panel by which the operator sets desired upper and lower positions for the hitch and a desired velocity at which the hitch should travel up and down. The operator then activates an input device to select raising or lowering the hitch. An electronic control system responds to that switch by operating an electrohydraulic valve to drive the piston-cylinder assembly so that the hitch moves in the designated direction and speed until the hitch reaches the selected position at which time the valve is closed. Specifically the electronic control system applies a given level of electric current to the electrohydraulic valve which opens the valve a corresponding degree thereby providing a related amount of fluid flow through the valve.
[0008] Electrohydraulic hitch valves typically have been designed with a mechanical flow compensator on the raise function. The flow compensator provides a constant flow rate (raise rate) at a given valve current regardless of the load on the hitch arms and regardless of other pressure demands of the hydraulic system. Flow compensation usually is not implemented on lower function of the hitch valve. This results in variable lowering rates for a given valve current. The lower rate varies due to different loads being placed on the hitch, as well as due to changes in hitch geometry as the hitch arms change position. The use of a mechanical flow compensation technique similar to that used during raise could provide a constant lowering rate for a given valve current, but doing so would add cost and complexity to the valve assembly.
[0009] As a consequence, there is a need for a hydraulic control system that provides flow compensation during both raise and lower operations.
SUMMARY OF THE INVENTION
[0010] A vehicle, such as a farm tractor, for example, has a hitch for towing an implement that can be raised and lowered by movement of the hitch. The hitch is moved by operating a valve to control the flow of fluid to and from a hydraulic actuator which is mechanically coupled to the hitch.
[0011] To operate the hitch, a hitch command is received from a device manipulated by the tractor operator, wherein the hitch command indicates a designated velocity for the hitch. A first error value is produced that denotes deviation of the force acting on the hitch from a reference force level. For example, one or more force sensors can be attached to the hitch to detect the force acting thereon. The hitch command is altered in response to the first error value, thereby producing a first adjusted command. The hitch is moved in response to the first adjusted command.
[0012] A second value is produced that relates to an actual velocity at which the hitch is moving. For example, a sensor can be attached to the hitch to provide a signal from which the actual velocity can be determined. A second error value denoting deviation of the actual velocity of the hitch from the commanded hitch velocity is derived. The first adjusted command is altered in response to the second error value, thereby producing a second adjusted command. The valve then is operated in response to the second adjusted command.
[0013] One embodiment of a vehicle, that incorporates the present hitch control method, has an electrically operated valve. A control system on the vehicle converts the operator command, providing the designated velocity, into an electric current level for operating the valve. The control system is configured with relationships between a hitch motion command values and electric current levels based on a reference force level is acting on the hitch. The present method for controlling the hitch adjusts for effects that deviation of the actual exerted external force from the reference force level has on operation of the valve and the hydraulic actuator.
[0014] The use of passive load force control provides a predictor of the hitch load to eliminate the overshoot/undershoot from active control. Active velocity correction further compensates during hitch motion travel to account for any load or hitch geometry changes that occur.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 illustrates a tractor pulling an agricultural implement;
[0016] FIG. 2 shows a typical three-point hitch on the tractor for attaching the implement;
[0017] FIG. 3 is a block diagram of an electrohydraulic system for operating the three-point hitch; and
[0018] FIG. 4 is a flowchart depicting the flow compensation technique according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] With initial reference to FIGS. 1 and 2 , an implement 10 , such as a multiple blade agricultural plow, is connected by a three-point hitch 12 to the rear of a tractor 14 . The hitch 12 comprises right and left drag links 16 and 18 , the proximal ends of which are pivotally attached to the tractor frame 17 by pins 15 . A pair of lift arms 20 and 22 , connected to the drag links 16 and 18 by lift links 24 and 25 , control the elevation of the drag links. Two hydraulic actuators 27 and 28 , in this case single acting lift hydraulic cylinders, are connected between the lift arms 20 and 22 and the tractor frame 17 to pivot the lift arms up and down with respect to that frame.
[0020] The distal ends of the drag links 16 and 18 are respectively attached to vertically extending legs 29 and 30 of a coupler 26 that has a cross bar 32 connected between the upper ends of the legs. A link hydraulic cylinder 34 is attached at one end to the cross bar 32 and at the other end to the tractor frame 17 by a pin 35 . A pair of lower lift hooks 36 and 38 project rearward from the bottom ends of legs 29 and 30 and an upper lift hook 40 is positioned in the middle of a cross bar 32 . The lift arms 20 and 22 move the coupler 26 bi-directionally along a principal axis “A” of coupling motion, which in this case is vertical.
[0021] The lower and upper lift hooks 36 , 38 and 40 cooperate with mating parts on a hitch structure of the implement 10 . Specifically the lower lift hooks 36 and 38 engage the lower hitch pins that extend laterally with respect to the frame of the implement. The implement also has a laterally extending upper hitch pin that is received in the upper lift hook 40 when the implement 10 is coupled to the tractor 14 . The trio of lift hooks 36 , 38 and 40 form the three points of the hitch 12 .
[0022] With reference to FIG. 3 , the electrohydraulic control system 50 for operating the three point hitch 12 comprises a hydraulic section 52 and an electronic section 53 . The hydraulic section 52 includes a tank 54 , which holds hydraulic fluid, and a pump 56 , that when driven by the engine of the tractor 14 sends pressurized hydraulic fluid from the tank through a supply line 58 . A supply line 58 is connected to a three-position, three-way electrohydraulic valve 60 and a tank return line 62 couples the valve to the tank 54 . The valve 60 has a workport 63 connected to two lift hydraulic actuators 27 and 28 , such as a pair of single-acting piston-cylinder assemblies having head chambers to which the workport is connected. It should be appreciated that the present flow compensation technique can be used with hydraulic sections having other configurations, such as where the valve workport 63 is connected to the cylinder rod chambers, those having only one hydraulic actuator, and those with one or two double-acting hydraulic actuators.
[0023] The valve 60 is operated by a solenoid 64 that is energized by an electric current from a controller 65 within the electronic section 53 of the control system 50 . The controller 65 may be a microcomputer-based device that includes processor 66 which executes instructions of a software control program, to be described, and a memory 67 for storing the instructions and data for the control program. A valve driver 69 responds to commands from the processor 65 by producing a variable electric current level for driving the solenoid 64 to proportionally operate the electrohydraulic valve 60 . The controller 65 further comprises an input/output (I/O) circuit 68 that has analog and digital ports to receive input signals from sensors and to interface with other devices on the tractor.
[0024] The input/output circuit 68 receives a signal from a position sensor 70 that indicates the vertical position of the coupler 26 of the three point hitch 12 . Any of various types of sensing mechanisms located at any of several locations on the hitch can be employed. For example, the position sensor 70 may be a linear device connected to one of the lift hydraulic actuators 27 or 28 to produce a signal as the piston rod extends and contracts from the cylinder body. Alternatively, a rotational type position sensor can be connected to one of the lift arms 20 or 22 to provide a signal indicating the rotational position of that arm with respect to the tractor frame 17 . With both of these sensing techniques, the signal from the position sensor 70 indicates a position that is geometrically related to the vertical position of the hitch coupler 26 with respect to the tractor frame 17 .
[0025] The input/output circuit 68 also receives signals from right and left force sensors 71 and 72 . For example, these sensors are standard clevis pin type sensors commonly incorporated into the pins 15 that couple the left and right drag links 16 and 18 to the tractor frame 17 . The force sensors 71 and 72 detect the load force that is exerted by an implement attached to the hitch. Because that the load force results the weight of the implement due to gravity, the load force is directed downward and tends to lower the hitch 12 . The present control system 50 is being described in the context of left and right sensors which have the advantage of measuring the different forces exerted on the lateral sides of the three-point hitch 12 by the implement of other apparatus attached to the hitch. Alternatively, a single clevis pin sensor can be used in the pin 35 that connects the link hydraulic cylinder 34 to the tractor frame 17 . Other types of sensors, sensing locations and sensing mechanisms can be employed to produce electrical signals indicating the magnitude of the external force acting on the three point hitch 12 . For example, the force acting on the hitch can be detected by sensing the hydraulic pressure produced in the hydraulic actuators 27 and 28 by that force.
[0026] A human interface 74 exchanges signals with the input/output circuit 68 of the controller 65 . This enables the operator of the tractor 14 to input configuration settings and send commands to the controller, thereby defining operation of the hydraulic section 52 . In particular as will be described, input switches 75 are used to select desired ultimate raised and lowered positions for the implement attached to the hitch 12 . A center-off, three-position, momentary contact toggle switch 76 enables the tractor operator to indicate that the hitch 12 should be raised and lowered. Other types of switches and input devices can be employed. The human interface 74 also has a display screen 77 by which information is presented to the tractor operator.
[0027] A speed input device 78 enables the tractor operator to designate a velocity at which the hitch is to be raised and lowered. The manufacturer of the tractor 14 has determined a maximum speed for lowering the hitch 12 and different positions of the speed input device 78 indicate hitch lowering speeds within a range between a defined minimum hitch speed and that maximum speed. The maximum speed also is stored in the memory 67 , as a constant reference velocity value. The signal from the speed input device 78 indicates a percentage of the maximum speed. The control system 50 is calibrated by the tractor manufacturer so that when a constant reference force level is exerted on the hitch, each speed indicated within that range causes the valve driver 69 to send an electric current level to the valve 60 so that the hydraulic actuators are driven to achieve the desired hitch velocity. Specifically, that electric current level when applied to the solenoid 64 , opens the hydraulic valve 60 to produce a fluid flow there through that suitably operates the hydraulic actuators 27 and 28 to move the hitch at the designated velocity. The result of the calibration process is a set of relationships between hitch motion command values and electric current levels for properly moving the hitch when the reference force level is acting on the hitch. The memory 67 of the controller 65 stores a look-up table containing the set of relationships that will be use to convert hitch motion commands into electric current levels for operating the hydraulic valve. It should be understood that when a force other than the reference force level is exerted on the hitch, the velocity to electric current conversion is slightly inaccurate and the hitch may not move at the designated velocity.
[0028] When the operator of the tractor 14 desires to raise or lower the hitch 12 , the operator moves the toggle switch 76 in one direction or the other from the center off position to indicate whether the hitch is to be raised or lowered. Assume for example that the hitch is to be lowered. Activation of the toggle switch 76 sends a hitch command that denotes the direction for hitch motion and a value indicating a desired speed as a percentage of the reference, or maximum speed. Thus that hitch command denotes a desired velocity for the hitch 12 .
[0029] The controller 65 responds to the hitch command by executing a hitch control program 80 depicted by the flowchart in FIG. 4 . The hitch control program 80 commences at step 82 by receiving the hitch command from the control panel 74 . Next at step 83 , the inputs from the left and right force sensors 71 and 72 are read by the controller 65 and processed to derive a net force referred to as the load force acting on the hitch 12 . One previous technique for deriving a load force simply averaged the right and left forces. Another technique calculated the load force according to the expression:
[0000] Load Force=Maximum(Right Force,Left Force)+GAIN*abs(Right Force−Left Force)
[0000] where GAIN is a predefined factor that specifies the sensitivity of the force difference.
[0030] Then at step 84 , a determination is made whether the hitch command designates that the hitch should be lowered or raised and in response the program execution branches to either step 85 or 86 , respectively. When the hitch 12 is lowering, the force of gravity acting on the implement 10 adds to the force from the hydraulic actuators to assist in lowering the hitch. Therefore, if the actual load force acting on the hitch is greater than a reference force level, that the manufacturer used to configure the hydraulic control system 50 and define the relationships between hitch motion command values and electric current levels, that additional force causes the hitch to lower at a faster rate than is designated by the hitch command from the operator. Similarly if the actual load force is less than that reference force level, the hitch will move downward at a slower rate than designated by the hitch command. Therefore, the present method compensates for the effects of those force differences by deriving a load error value E L based on the reference force level. In the lowering mode, the hitch control program 80 branches to step 85 where the load error value E L is the square root of the ratio of the reference force level over the actual load force derived from the force sensors 71 and 72 at step 83 .
[0031] In the hitch raising mode, the effects due to the actual load force differing from the reference force level are inverted and the force of gravity acting on the implement counteracts the force from the hydraulic actuators and thus the hitch motion. Therefore, a greater actual load force than the reference force level causes the control system 50 to raise the hitch at a slower rate than desired, and a lesser actual load force than the reference force level causes the control system 50 to raise the hitch faster than the designated rate. Thus in the hitch raising mode, step 86 is executed instead of step 85 and the force ratio used to derive the load error value E L is the square root of the actual load force over the reference force level.
[0032] The load error value E L then is employed at step 87 to adjust the operator's hitch command. This is accomplished by multiplying the hitch command from the human interface 74 by the load error value E L to produce a first adjusted command. The first adjusted command has a value that is compensated for the effect that deviation of the actual load force from the reference force level has on hitch motion. The first adjusted command has a smaller value than the original hitch command when either the actual load force is greater than the reference force level in the hitch lowering mode, or the actual load force is less than the reference force level in the raising mode. In those situations, the actual load force assists the desired hitch motion and less than the calibration hydraulic force is needed to move the hitch at the designated velocity. Inversely, the first adjusted command has a larger value than the original hitch command when the actual load force either is smaller than the reference force in the hitch lowering mode, or is greater than the reference force in the raising mode. In those latter situations the actual load force counteracts the desired hitch motion and more than the calibration hydraulic force is needed to move the hitch at the designated velocity from the operator command.
[0033] At step 88 the first adjusted command is converted into an electric current level using the motion command value to electric current level relationships established during control system calibration for the given reference load force acting on the hitch. That electric current level is applied by the valve driver to the solenoid 64 of the hydraulic valve 60 at step 89 . This results in a fluid flow through the hydraulic valve that drives the actuators 27 and 28 causing hitch 12 to begin moving.
[0034] Producing the first adjusted command in the manners described above results in production of an electric current level that operates the valve 60 to compensate for actual load forces that are different than the given reference load force used during calibration. Thus, when the actual load force is such that the hitch does not require as much hydraulic force to move at the desired speed, a smaller electric current level is derived using the calibrated command to electric current relationship than would be produced for the given reference load force. In response to that smaller electric current level, the valve 60 opens less to apply a lower flow rate to the hydraulic actuators 27 and 28 . When the actual load force is such that the hitch requires more hydraulic force to move at the desired speed, resultant electric current level is larger and the valve 60 opens more to apply a higher flow rate to the hydraulic actuators.
[0035] The control program 80 then advances to a section that provides velocity feedback control which determines any error between the actual velocity at which the hitch 12 is moving and the desired velocity as indicated by the original hitch command. Such an error then is used to alter the first adjusted command so that the electric current applied to the hydraulic valve 60 will result in the hitch moving at the desired velocity.
[0036] This section of the control program 80 commences at step 90 at which the controller 65 reads the signal from the position sensor 70 to obtain an indication of the position of the hitch. At step 92 , the derivative of the position signal is calculated to determine the actual velocity of the hitch. Other sensors and sensing techniques can be employed to detect the actual velocity of the hitch 12 . Next at step 94 , any difference between the actual velocity and the velocity indicated by the original hitch command is determined, thereby producing a velocity error value E V . Note that the original hitch command is expressed as a percentage of the reference velocity, e.g. that maximum velocity defined by the tractor manufacturer for system configuration. Therefore, the arithmetic expression at step 94 uses a ratio of the actual velocity to that reference velocity to determine the velocity error value from the hitch command.
[0037] At step 95 , the velocity error value is summed with the first adjusted command to produce a second adjusted command that indicates a command value that is necessary for the control system to produce an electric current to properly drive the valve 60 in a manner that achieves the hitch velocity desired by the tractor operator. In other words, if the actual velocity determined at step 92 is less than the desired velocity, the velocity error value E V will be positive and produces a second adjusted command that is greater than the first adjusted command. In this case, the valve will open slightly more to drive the hydraulic actuators 27 and 28 a greater amount. In the opposite case, in which the actual velocity is greater than that desired by the tractor operator, the velocity error value E V will be negative. That negative velocity error value produces a second adjusted command that is less than the first adjusted command so that the valve is closed slightly to drive the hydraulic actuators 27 and 28 less vigorously to achieve the desired hitch velocity.
[0038] The second adjusted command then is converted at step 96 into a corresponding electric current level using the calibrated hitch motion command value to electric current level relationships defined during control system configuration. The so derived electric current level then is applied to the valve driver 69 at step 98 to properly operate the valve 60 and drive the hydraulic actuators accordingly.
[0039] The control program 80 then advances to step 99 where the actual position of the hitch 12 , that was sensed at step 90 , is compared to the desired ultimate position as set by the tractor operator via input switches 75 . If the hitch 12 has not reached the desired ultimate position, the program execution returns to step 90 for another pass through the velocity feedback section. Eventually the hitch 12 will reach the desired ultimate position at step 99 causing the control program to terminate.
[0040] The foregoing description was primarily directed to a preferred embodiment of the invention. Although some attention was given to various alternatives within the scope of the invention, it is anticipated that one skilled in the art will likely realize additional alternatives that are now apparent from disclosure of embodiments of the invention. Accordingly, the scope of the invention should be determined from the following claims and not limited by the above disclosure. | A hitch on a vehicle is raised and lowered by a hydraulic actuator controlled by an electrically operated valve. A control system receives a command that indicates a designated velocity and uses the command to operate the valve. Based on a reference external force exerted on the hitch, the control system is configured with relationships for converting a plurality of command values to corresponding electric current levels for operating the valve. The control system compensates for effects due to differences between the actual force acting on the hitch and the reference external force. Velocity feedback adjusts the electric current level applied to the valve. The passive load force control provides a predictor of the hitch load force to eliminate overshoot/undershoot of hitch motion. During hitch motion, the velocity feedback also compensates for effects due to load and hitch geometry changes that occur. | 0 |
BACKGROUND OF THE INVENTION
The invention relates to a process for measuring the twist of a running, elongate test body, such as, for example, of a yarn or of a wire rope, by optical scanning of its surface and analysis of the scanning signal obtained in this case.
In a process of this type which is known from DE-A-3,628,654, a thread is grazingly acted upon by light, and specifically in such a manner that a part of the light beam is shaded off by thread and the part permitted to pass by the thread impinges on a light receiver. As a result of this, it is possible to detect certain structural alterations which are a measure of the thread period. Since this process, in which the profile is scanned to a certain extent, can be employed only when a detectable profile is present at all, this process is not suitable for the measurement of the twist of yarns.
A process of the initially mentioned type for the measurement of the twist of yarns is to be indicated by the invention.
SUMMARY OF THE INVENTION
According to the invention, this object is achieved in that the test body is illuminated by at least one light source and the light reflected by the test body is imaged onto a diaphragm and is measured by at least one photoelectric receiver, the output signal of which is investigated for periodicities caused by irregularities included in the test body, and in that the twist is derived from the wavelength or from the frequency of these periodicities.
Thus, the invention proceeds from the novel finding that the twist of yarns and the like leads to the bindingin of irregularities, which occur periodically on account of the twist. If the surface of a continuous test body is investigated for such periodicities, then the twist can be determined from these; this would not be possible by a simple scanning of the yarn profile.
The invention further relates to a device for carrying out the process according to the invention. This device is characterized by at least one light source for illuminating the test body, a diaphragm, an optical system for imaging the light reflected by the test body onto this diaphragm, at least one photoelectric receiver disposed in the beam path downstream of the diaphragm and an evaluation unit associated with this photoelectric receiver.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in greater detail herein below with reference to an illustrative embodiment in the drawings; in the drawings:
FIG. 1A shows a diagrammatic representation of a device according to the invention,
FIG 1B shows yet another preferred embodiment of the present invention, and
FIGS. 2,3 show diagrams for explaining the operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1A shows a piece of a yarn G, which is conveyed by guide and transport means (not shown) in the direction of the arrow P through a device for measuring the yarn twist. As represented, this measuring device includes two light sources 1, 1' for illuminating the yarn G with a respective beam L, L', a diaphragm 2, onto which the beam R reflected by the yarn is imaged, a photoelectric receiver 3 disposed in the beam path downstream of the diaphragm and an evaluation unit 4 associated with this photoelectric receiver. Respective appropriate optical systems 5, 5' and 6 are provided in the beam path of the two beams L, L' and of the reflected beam R. A further lens 7 is situated between diaphragm 2 and photoelectric receiver 3. The light sources 1, ' are preferably formed by light-emitting diodes, so-called LEDs.
Before the measuring device is described in greater detail, the measurement process is to be explained now with reference to FIGS. 2 and 3: any yarn G exhibiting a twist or also any wire rope or any rope and the like exhibits, on account of the twist, certain irregularities with respect to its cross-section, and specifically, in particular, deviations from the cross-sectional shape. These characteristic deviations occur periodically, in which case the spacing between two successive such irregularities or, in other words, the length of the period thereof, represents a direct measure of the twist. This is so because the yarn twisted exactly once through 360° over such a period.
If the yarn G is illuminated at a small angle to its longitudinal axis, then the said irregularities become clearly visible as bright or dark positions, as is indicated in FIG. 2 by the hatched regions B. The length of the period, or, in other words, the wavelength of the irregularities, is designated by d. If T designates the twist of the yarn as the number of turns per unit length, then the following is applicable for the period d:d=1/T. Customary values for T are, for example, between 300 and 1,500 turns per meter. In the case of n-fold threads, the principal period occurs at d'=d/n, where here d designates the period of the thread twist; thus, for example in the case of 2-fold threads, the principal period is to be expected at d'=d/2.
The brightness of the impinging light beam R on the photoelectric receiver 3 (FIG. 1A) then increases periodically, and if the output signal of the photoelectric receiver 3 is evaluated in the evaluation unit 4 by Fourier transformation (FFT) or autocorrelation, a clearly detectable maximum is obtained at the period of the irregularities. In the case of very well defined structures, such as, for example, in the case of wire threads or filamentary threads, this analysis can, in certain circumstances, even take place by simple determination of a trigger threshold and subsequent counting.
The analysis by means of Fourier transformation is diagrammatically represented in FIG. 3; in this case, the frequency f is plotted on the abscissa and the amplitude A on the ordinate. A clearly detectable maximum is obtained at a specified frequency f1; in this case, the following then applies for the twist; T=f1/v, if v designates the draw-off speed of the yarn G. In the case of analysis by means of autocorrelation, the length d of the period is obtained directly.
In the case of yarns with twist, cross-sectional fluctuations also virtually always occur, which, however, do not necessarily lead to irregularities which are periodic, i.e. evaluable for the determination of the twist. Accordingly, it is advantageous to compensate the cross-sectional fluctuations; this takes place, as represented in FIG. 1A, by the use of two light sources 1 and 1', which illuminate the yarn G at differing angles of incidence. The angle of incidence a of the beam L is relatively small and is between 5° and 40°, preferably 5°, and the angle of incidence a' of the beam L' is steeper and is between 60° and 85°, preferably 85°.
If the two light sources L and L' are differently modulated, then, with corresponding demodulation of the signal, a single common photoelectric receiver 3 can be employed; in this case, the signal component originating from the light source 1 is divided, in this, by that originating from the light source 1'. However, it is also possible to use two light sources 1, 1', which emit light of differing wavelengths. In this case, the reflected beam R must be divided on the receiver side, and the individual components originating from the two light sources 1, 1' must be distributed by appropriate filters to two different photoelectric receivers.
A further illumination variant consists in using two light sources 1 with a small and a light source with a very steep angle of incidence of up to about 90°; in this case, in relation to FIG. 1B the two light sources 1 are disposed symmetrically on both sides of the reflected beam R and the third light source is situated between the other two. This arrangement leads, on the one hand, to an even better emphasising of periodic structures and, on the other hand, to the elimination of disturbing influences originating, for example, from neps and the like.
The following conditions are applicable to the diaphragm 2: if the yarn exhibits T twists per unit length, and is imaged onto the diaphragm 2 at the magnification K:1, then the diaphragm 2 must be narrower than K/T in the direction of the length of the yarn, in order that it should still be possible to achieve good detection of periodic components of the twist. In the case of yarns, in the transverse dimension the diaphragm 2 is advantageously restricted to the approximate detection of the yarn body, so that the hairiness does not have an excessively disturbing effect. In order to achieve further reduction of the disturbing influences of the hairiness, the yarn G can be singed. If the yarn G is very strongly singed, then it is possible to obtain insights into the twist in the yarn body; this can, on the one hand, be very much desired in the case of rotor yarns, but is, on the other hand, destructive and should therefore be restricted to random samples.
Finally, it should furthermore be mentioned that the test body G should be guided in a vibration-free manner as far as possible, since with light incident at a small angle vibrations have a disturbing effect. For this reason, it is advantageous to guide the test body G directly at the measurement position via a deflecting component.
The described measurement device can be constructed in a very compact manner, and is therefore outstandingly suitable for use as measurement module in a device for the automatic determination of characteristic quantities of textile test material, as is described, for example, in Swiss Patent Application No. 02,823/86-2, and is known under the designation USTER TESTER (USTER--registered trade mark of Zellweger Uster AG). | A test body is illuminated by at least one light source obliquely to its direction of travel, and the reflected light is imaged onto a diaphragm and fed to a photoelectric receiver. Its signal is investigated, in an evaluating unit, for periodicties which are caused by irregularities included in the test body as a result of the twist and the wavelength of which represents a measure of the twist. A rapid and precise measurement of the twist of yarns is made possible thereby. | 3 |
RELATED APPLICATION(S)
[0001] This application is a utility filing claiming priority of provisional application 61/165,289 filed on 31 Mar. 2010.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention generally relates to an automated luminaire, specifically to an iris for use within an automated luminaire.
BACKGROUND OF THE INVENTION
[0003] Luminaires with automated and remotely controllable functionality are well known in the entertainment and architectural lighting markets. Such products are commonly used in theatres, television studios, concerts, theme parks, night clubs and other venues. A typical product will commonly provide control over the pan and tilt functions of the luminaire allowing the operator to control the direction the luminaire is pointing and thus the position of the light beam on the stage or in the studio. Typically this position control is done via control of the luminaire's position in two orthogonal rotational axes usually referred to as pan and tilt. Many products provide control over other parameters such as the intensity, color, focus, beam size, beam shape and beam pattern. The beam pattern is often provided by a stencil or slide called a gobo which may be a steel, aluminum or etched glass pattern. The products manufactured by Robe Show Lighting such as the ColorSpot 700E are typical of the art.
[0004] The optical systems of such luminaires may include a gate or aperture through which the light is constrained to pass. Mounted in or near this gate may be devices such as gobos, patterns, irises, color filters or other beam modifying devices as known in the art. The use of a variable aperture or iris diaphragm allows control over the size of the output beam and thus the size of the image projected onto a surface. When placed in the optical path within a luminaire removed from a focal point the iris may be used to serve the role of a variable dimmer either progressively decreasing or increasing the light intensity as the iris either closes or opens respectively.
[0005] FIG. 1 illustrates a multiparameter automated luminaire system 10 . These systems commonly include a plurality of multiparameter automated luminaires 12 which typically each contain on-board a light source (not shown), light modulation devices, electric motors coupled to mechanical drives systems and control electronics (not shown). In addition to being connected to mains power either directly or through a power distribution system (not shown), each luminaire is connected is series or in parallel to data link 14 to one or more control desks 15 . The luminaire system 10 is typically controlled by an operator through the control desk 15 .
[0006] FIG. 2 illustrates a prior art automated luminaire 12 . A lamp 21 contains a light source 22 which emits light. The light is reflected and controlled by reflector 20 through an aperture or imaging gate 24 and then through a variable aperture 23 . The resultant light beam may be further constrained, shaped, colored and filtered by optical devices 26 which may include dichroic color filters, gobos, rotating gobos, framing shutters, effects glass and other optical devices well known in the art. The final output beam may be transmitted through output lenses 28 and 29 which may form a zoom lens system.
[0007] Variable aperture 23 is most commonly constructed as an iris diaphragm which contains a series of overlapping leaves that may be adjusted by a single lever or gear to control the effective size of the aperture.
[0008] FIGS. 3 , 4 , 5 , 6 , 7 and 8 illustrate the construction and operation of a prior art example of an iris diaphragm 30 . Iris diaphragms are well known in the art and have been utilized as variable apertures in luminaires for many years. Iris diaphragms in automated luminaires typically employ multiple thin leaves 36 which are constrained on both sides to avoid problems caused by buckling of the thin leaves 36 due to the inherent high temperature operating conditions frequently found in an automated luminaire.
[0009] FIGS. 3 , 4 , 5 , 6 , 7 and 8 illustrate such an iris diaphragm where both ends of the leaves 36 are constrained by housing 38 and stationary ring 34 . Handle 32 of actuator ring 37 to which one end of each of the leaves 36 are pivotally attached. The other end of leaves 36 have tabs 35 which ride in slots 39 in stationary ring 34 which is in turn fixed to stationary housing 38 constraining the movement of the leaves 36 . Leaves 36 are held within slots 39 of the stationary rung 34 by pressure applied to the underside of actuator ring 37 by stationary housing 38 . As the handle 32 is rotated in one direction, the leaves individually rotate about their pivoted ends they are constrained by tab 35 and slot 39 and occlude an increasing amount of the central aperture space. When the handle 32 moves in the opposite direction the leaves 36 occlude a decreasing amount of the central aperture space.
[0010] FIG. 3 illustrates an iris diaphragm 30 in a position where actuator 32 is at one extreme of its motion and leaves 36 are fully thus maximizing the central aperture.
[0011] FIG. 4 illustrates an iris diaphragm 30 in a position where actuator 32 is at its midpoint and leaves 36 have been rotated to their midpoint thus occluding a portion of the central aperture. Note that the resultant aperture formed by the juxtaposition of the leaves is not a true circle. The more leaves 36 that are used in the design the closer to circular the resultant aperture. Using more leaves 36 also tends to increase the friction in the system and the risk of problems in opening and closing of the iris particularly in high temperature conditions.
[0012] FIG. 5 illustrates an iris diaphragm 30 in a position where actuator 32 is at the other extreme of its motion and leaves 36 are fully rotated thus occluding the majority of the central aperture. It can be seen that as previously discussed actuator ring 37 is in contact with the inside surface of fixed housing 38 and thus there is considerable friction between these two surfaces particularly in higher temperature or in varying temperature conditions. Prior art devices have made various attempts to minimize this friction by using lubricants or coatings on the mating surfaces of actuator ring 37 and stationary housing 38 however these coatings and lubricants frequently cause increased friction at the high operating temperatures of automated luminaires. Increased friction in the rotation of actuator ring 37 may result in jerky or steppy movement visible to the audience and, in extreme cases, may result in the iris diaphragm becoming so stiff to move that the small stepper motor frequently utilized to move actuator 32 is unable to overcome that friction and the iris becomes stuck. Such a system is also prone to increased problems due to accumulation of dust and dirt as the fixture ages and is maintained. Further problems may arise from the poor thermal transfer of heat from leaves 36 through actuator ring 37 to stationary housing 38 .
[0013] There is a need for an improved iris diaphragm mechanism for automated luminaire which provides reduced and consistent friction between the operating components and improved thermal transfer to allow operation at a wide range of operating temperatures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which like reference numerals indicate like features and wherein:
[0015] FIG. 1 illustrates a typical automated lighting system;
[0016] FIG. 2 illustrates a typical automated luminaire;
[0017] FIG. 3 illustrates a prior art iris diaphragm;
[0018] FIG. 4 illustrates a prior art iris diaphragm;
[0019] FIG. 5 illustrates a prior art iris diaphragm;
[0020] FIG. 6 illustrates a prior art iris diaphragm;
[0021] FIG. 7 illustrates a prior art iris diaphragm;
[0022] FIG. 8 illustrates a prior art iris diaphragm;
[0023] FIG. 9 illustrates an embodiment of the invention;
[0024] FIG. 10 illustrates an embodiment of the invention;
[0025] FIG. 11 illustrates an embodiment of the invention;
DETAILED DESCRIPTION OF THE INVENTION
[0026] Preferred embodiments of the present invention are illustrated in the FIGUREs, like numerals being used to refer to like and corresponding parts of the various drawings.
[0027] The present invention generally relates to an automated luminaire, specifically to the configuration of an iris diaphragm within such a luminaire such that the mechanism supporting movement of the iris diaphragm provides reduced and consistent friction between the operating components at a wide range of operating temperatures.
[0028] FIG. 9 illustrates an exploded drawing of an embodiment of the invention. Iris diaphragm 40 comprises a set of leaves 46 that may be rotated to variably occlude a central aperture.
[0029] The first, outer, ends (not shown) of leaves 46 are pivotally attached to stationary housing 48 such that leaves 46 may rotate across the central aperture. The second, inner, ends of leaves 46 have tabs 45 which ride in slots 49 in actuator ring 44 . Actuator ring 44 may be rotated by an external motor drive system (not shown); such motorized operation is well known in the art. The motor may be of a type selected from a list comprising but not limited to, stepper motors, servo motors, and linear actuators. As actuator ring 47 rotates it links the rotation through slots 49 to tabs 45 on leaves 46 . As leaves 46 individually rotate about their pivoted ends they are constrained by tab 45 and slot 49 to occlude an increasing amount of the central aperture. Leaves 46 are held within slots 49 of the actuator ring 44 by pressure applied to the underside of actuator ring 44 through ball bearing race 41 to stationary housing 48 .
[0030] Bearing race 41 provides a first improvement over the prior art by providing a controlled low friction bearing surface through ball bearing race 41 between the actuator ring 44 and stationary housing 48 . Ball bearing race 41 provides smooth and consistent motion for the actuator ring 44 .
[0031] A further improvement of the invention over the prior art is provided by fixing the stationary end of leaves 46 directly to the stationary housing 48 rather than through an intermediate ring (shown as 37 in FIG. 6 ). This direct connection to stationary housing 48 provides an improved heat path with lower thermal resistance from leaves 46 to stationary housing 48 and thus to the chassis of the luminaire. This allows heat from the leaves heated by the light from the luminaire to pass readily from the leaves thus keeping them at a lower temperature and reducing distortion and warping due to excessive heat.
[0032] FIGS. 10 and 11 illustrate an embodiment of the invention in its final assembled state.
[0033] While the disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the disclosure as disclosed herein. The disclosure has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the disclosure. For Example, although the invention is described as holding the housing 48 stationary and rotating actuator ring 44 the invention is not so limited and this operation may be reversed by holding the actuator ring stationary and rotating the housing without departing from the spirit of the invention. | Described are an improved automated luminaire 12 and luminaire systems 10 employing an improved iris 40. The iris 40 is improved by simultaneously improving the thermal conductivity of the system for wicking away heat and the use of a bearing race 41 within the iris structure 40. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the right of priority under 35 U.S.C. §119 (a)-(d) of German Patent Application Number 10 2005 052 813.9, filed Nov. 25, 2005.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to the preparation of new isocyanate-functional prepolymers from styrene-allyl alcohol copolymers and mehtylenediphenyl diisocyanate (MDI), and also to their use as moisture-curing polyurethane (PU) coatings particularly suitable for corrosion control.
[0003] MDI prepolymers based on polypropylene oxides are used for the corrosion-control coating of steel.
[0004] The preparation of styrene-allyl alcohol copolymers or their alkoxylation products and their crosslinking with (blocked) isocyanates is well established. They can be prepared in accordance with U.S. Pat. No. 3,969,569 and U.S. Pat. No. 4,144,215. According to the teaching of U.S. Pat. No. 3,969,569, however, coatings of this kind, comprising blocked isocyanates and styrene-allyl alcohol copolymers, have to be baked at high temperatures of more than 225° C., for reasons which include the deblocking of the NCO groups, which is needed for crosslinking. With unblocked isocyanates, moreover, according to U.S. Pat. No. 4,144,215, styrene-allyl alcohol copolymers can be applied only as a two-component system.
[0005] It was an object of the present invention, then, to find a coating system which has the desirable properties of the styrene-allyl alcohol copolymer PU coating materials, such as water repellence, but can be applied as a one-component system and is curable at room temperature.
[0006] It has now been found that it is possible to prepare prepolymers from styrene-allyl alcohol copolymers with MDI in an equivalent ratio of OH to NCO groups of 1:≧2. The prepolymers can be used to give moisture-curing coating materials having good corrosion-control properties on critical substrates.
SUMMARY OF THE INVENTION
[0007] The invention accordingly provides a process for preparing PU prepolymers comprising reacting one or more OH-functional copolymers of vinylaromatics and allyl alcohol with methylenediphenyl diisocyanate (MDI), the equivalent ratio of OH to NCO groups being 1:≧2.
[0008] The OH to NCO equivalent ratio is preferably 1:2 to 1:50, more preferably 1:2 to 1:20.
[0009] The invention further provides the prepolymers obtainable in accordance with the invention, and also coating systems based on these prepolymers.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] The prepolymers of the invention are preferably prepared as follows: over a period of 0.5 to 8 h a solution of the copolymer of vinylaromatics and allyl alcohol in 0.3 to 3 times the amount, by weight based on the copolymer, of a non-isocyanate-reactive solvent, is metered into MDI in an equivalent ratio of (OH groups to NCO groups) 1:2 to 1:20.
[0011] Copolymers of vinylaromatics and allyl alcohol for the purposes of the invention are, for example, copolymers of allyl alcohol and styrene, 3-methylstyrene, 4-methylstyrene, alpha-methylstyrene, 4-tert-butylstyrene, 4-chlorostyrene, 3-chlorostyrene, 4-bromostyrene, 3-bromostyrene, 2-trifluoromethylstyrene, 3-trifluoromethylstyrene, 4-trifluoromethylstyrene, 4-cyanostyrene, alkyl esters of 4-vinylbenzoic acid and/or mixtures thereof, preferably of allyl alcohol and styrene.
[0012] The copolymers of vinylaromatics and allyl alcohol can be prepared by free-radically copolymerizing the vinylaromatics with allyl alcohol.
[0013] The copolymers may also be prepared by reducing copolymers of the vinylaromatic and alkyl acrylates or acrylic or maleic acid derivatives, such as maleic anhydride, or fumaric acid derivatives, with metal hydrides, such as lithium alanate, but the free-radical copolymerization with allyl alcohol is the preferred path.
[0014] Copolymers of this kind of vinylaromatics and allyl alcohol preferably have an OH content of 2% to 10% by weight, more preferably of 3% to 8.5% by weight, a preferred molar mass (number average) of 800 to 5000 g/mol and a preferred molar mass (weight average) of 1500 to 11 000 g/mol.
[0015] The methylenediphenyl diisocyanate (MDI) is typically an isomer mixture with at least 80% by weight of the monomeric diisocyanate isomers 2,2′-, 2,4′- and 4,4′-MDI.
[0016] Preference is given to an isomer mixture with at least 90% by weight of the monomeric diisocyanate isomers 2,2′-, 2,4′- and 4,4′-MDI, particular preference to an isomer mixture with at least 95% by weight of the monomeric diisocyanate isomers 2,2′-, 2,4′- and 4,4′-MDI, and very particular preference to an isomer mixture with at least 98% by weight of the monomeric diisocyanate isomers 2,2′-, 2,4′- and 4,4′-MDI.
[0017] It is preferred to use isomer mixtures of the aforementioned kind in which the sum of the monomeric diisocyanate isomers comprises at least 90% by weight of 4,4′-MDI and 2,4′-MDI, more preferably at least 95% by weight of 4,4′-MDI and 2,4′-MDI, and with particular preference at least 98% by weight of 4,4′-MDI and 2,4′-MDI.
[0018] The isomer mixtures used may contain up to 25% by weight of MDI oligomers (consisting of at least three aromatics joined via methylene bridges, each aromatic bearing one isocyanate group), preferably up to 15% by weight of MDI oligomers, more preferably up to 5% by weight of MDI oligomers, and very preferably up to 2% by weight of MDI oligomers.
[0019] Non-isocyanate-reactive solvents for the purposes of the invention are aliphatic, aromatic or araliphatic solvents which do not contain any cerivitinov-active hydrogen atoms but do preferably contain ether groups and/or ester groups and/or halogen atoms and/or nitrile groups and/or amide groups. Examples of suitable solvents include methoxypropyl acetate, methoxyethyl acetate, ethylene glycol diacetate, propylene glycol diacetate, glyme, diglyme, dioxane, tetrahydrofuran, dioxolane, tert-butyl methyl ether, ethyl acetate, chloroform, methylene chloride, chlorobenzene, o-dichlorobenzene, anisole, 1,2-dimethoxybenzene, phenyl acetate, N-methyl-2-pyrrolidone, dimethylformamide, N,N-dimethylacetamide, dimethyl sulphoxide, acetonitrile, phenoxyethyl acetate and/or mixtures thereof, preferably solvents containing ether and ester groups, such as methoxypropyl acetate.
[0020] Some or all of any excess MDI can be removed, following prepolymer formation, by vacuum distillation, preferably thin-film distillation.
[0021] The invention further provides moisture-curing coating materials comprising the prepolymers of the invention and binders, the prepolymer content being preferably at least 50% by weight, more preferably 60% to 90% by weight, based on the sum of prepolymer and binder.
[0022] These moisture-curing coating materials can be applied as one-component systems.
[0023] As additional binders, the moisture-curing coating materials may comprise other polyisocyanates or isocyanate-functional prepolymers formed from polyalkylene oxides and polyisocyanates, preferably polypropylene oxides having OH functionalities of 2 to 4 and molar masses (number average) of 400 to 6000 g/mol and aromatic polyisocyanates, such as TDI, TDI trimers, TDI adducts and MDI.
[0024] Further possible ingredients of the coating materials include pigments, active rust prevention pigments, corrosion inhibitors, fillers, barrier-effect fillers (plated-shaped phyllosilicates or phylloaluminosilicates, graphite or aluminium flakes) and nanofillers (such as clays and aluminium silicates).
[0025] In addition it is possible for catalysts (tin compounds, amines, amidines, guanidines, zinc compounds, cobalt compounds, bismuth compounds, lithium salts, such as lithium molybdate, magnesium salts, calcium salts) and dryers (such as tosyl isocyanate, reactive aromatic isocyanates or orthoformates) for increasing storage stability to be present.
[0026] Based on solids, the coating materials contain preferably at least 5% to 100% by weight of non-isocyanate-reactive solvents.
[0027] The coating materials are cured typically at a temperature of 0 to 80° C., preferably at a temperature of 10 to 70° C more preferably at a temperature of 15 to 50° C.
[0028] The coating materials serve preferably for coating critical steel substrates from which rust has been removed only by means of simple measures (surface pre-treatment ST2 in accordance with ISO 12944-4).
[0029] The coating materials of the present invention are distinguished over coatings of the prior art primarily by improved corrosion control, as demonstrated in the following examples.
EXAMPLES
[0000] Measurement Methods:
[0000]
Viscosity: Rotational viscometer VT 550 from Haake GmbH, Karlsruhe, DE, MV-DIN cup for viscosity<10 000 mPa·s/23° C., SV-DIN cup for viscosity>10 000 mPa·s/23° C.
NCO content: Back-titration with 1 mol/l HCl following reaction with excess dibutylamine in acetone, based on DIN EN ISO 11909
[0032] All percentages below are by weight unless otherwise noted.
Preparation of Inventive Prepolymers (Examples 1-6)
[0000] General Working Procedure:
[0033] A solution of a styrene-allyl alcohol copolymer (SAA) in methoxypropyl acetate (MPA) was added dropwise at 90° C. over 3 hours to 1000 g of a 1:1 mixture of 2,4′- and 4,4′-MDI and the mixture was stirred until a constant NCO value was reached.
[0000] The SAAs Used Were
[0034] SAA-100® from Lyondell AG, US, having an OH content of 6.4% by weight and a molar mass M n of 1400 g/mol and M w of 3100 g/mol and
[0035] SAA-101® from Lyondell AG, US, having an OH content of 7.7% by weight and a molar mass M n of 1200 g/mol and M w of 2600 g/mol.
SAA-101 SAA-100 MPA Viscosity NCO content Example [g] [g] [g] [mPas] [%] 1 250 350 430 18.3 2 300 420 1060 15.3 3 350 490 3750 13.5 4 250 350 280 17.5 5 300 420 817 15.7 6 350 490 2180 13.9
Coating Formulation (Examples 7-12 Comparative Example)
[0000] General Working Instructions:
[0036] The mixture below was used as binder:
Prepolymer prepared according to one of Examples 1-6 155.4 g Desmodur ® E14 (TDI polypropylene oxide prepolymer 54.4 g having an NCO content of 3.3% [Bayer MaterialScience AG, Leverkusen, DE]) for elasticization Bayferrox ® 130 BM (iron oxide pigment from Lanxess, 44.5 g Leverkusen, DE) Heucophos CHP ® (calcium hydrogen orthophosphate, 58.9 g active rust prevention pigment, from Heubach AG, Langelsheim, DE) Talc ST 30 ® (filler from Luzenac AG, Paris, FR) 64.3 g Disperbyk ® 180 (dispersing additive from Byk Chemie AG, 3.5 g Wesel, DE) Byk ® A 530 (deaerating agent from Byk Chemie AG, 1.6 g Wesel, DE) Additive TI ® (dryer, tosyl isocyanate, from Borchers AG, 27.2 g Langenfeld, DE) Additive OF ® (dryer, tosyl triethyl orthoformate, from 13.0 g Borchers AG, Langenfeld, DE)
0.2 g of Metatin (dibutyltin acetylacetonate) [Acima Buchs, Switzerland] was added to the overall formula, which was then applied by brush in an approximate film thickness of 80 μm to an ST2-pretreated steel panel. The coatings were cured at room temperature for one day (ST2-pretreated: cleaned by using a wire brush, in accordance with ISO 12944-4).
[0037] Testing was carried out by means of a salt spray test (scoring and weathering) in accordance with SA DIN 53167. The test was ended when sub-film corrosion at the crack and/or severe rust perforation was observed.
Time to end of test Example Prepolymer [weeks] 7 1 5 8 2 6 9 3 8 10 4 5 11 5 8 12 6 5 Comparative Commercial prepolymer for moisture- 2 curing PU coating materials: Desmodur ® E23 (MDI on polypropylene oxides, from Bayer MaterialScience AG)
[0038] The prepolymers of the invention produce much more effective corrosion control the prepolymers in accordance with the abovementioned prior art that have been employed hitherto for this purpose.
[0039] Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims. | The present invention relates to the preparation of new isocyanate-functional prepolymers from styrene-allyl alcohol copolymers and MDI, and also to their use as moisture-curing polyurethane coatings for corrosion control. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates generally to fluid coupling devices for coupling the ends of two fluid-carrying conduits, and, more particularly, to an improved zero-spill double ball valve powered emergency release coupling in which two fluid-carrying conduits, each having a ball or plug valve received therein, are prevented from being decoupled unless both ball or plug valves are moved to a closed position prior to decoupling.
Coupling devices utilizing rotary valve elements that move between open and closed positions to regulate fluid flow are generally known. A problem exists where, upon closing of the two valve elements in such a coupling prior to decoupling, a certain amount of fluid becomes trapped in the flow passage between the two valve elements. Upon separation of the coupling or conduit ends, the trapped fluid may leak into the environment. To address this problem, it is known to use complementary ball valve elements in which one of the valve elements has a concave recess extending radially inward from its outer surface which is adapted to receive a convex portion of the other ball valve when the coupling ends are joined. The use of such complementary valve elements requires, however, that the valve element having the concave recess is closed first, positioning the concave recess adjacent to the other valve element in order to receive the convex portion. If the coupling is disconnected prior to proper zero-spill positioning of the valve elements spilling may occur. Thus, when the need arises to quickly separate the zero-spill coupling in emergency situations, the coupling must be provided with fail-safe means for regulating the closing sequence of the valve elements prior to separation and for preventing disconnection of the coupling prior to zero-spill positioning of the valve elements.
SUMMARY OF THE INVENTION
The present invention provides fail-safe means for regulating the closing sequence of ball valve elements in a fluid coupling during quick disconnection in emergency situations and for preventing disconnection of the coupling until the valve elements are rotated to zero-spill position.
The present invention includes two open-ended fluid conduit ends adapted for coupling in sealing engagement. The conduit ends each contain a ball valve element adapted to cooperate with the other ball valve element in a zero-spill manner. A mechanical or hydraulic actuator corresponding to each valve element is provided for rotating each valve element between opened and closed positions. A mechanical connection is provided between the actuators to regulate the operating sequence of one of the actuators in response to the other actuator. A locking mechanism for preventing decoupling prior to zero-spill positioning of valve elements includes a shear pin designed to shear, enabling disconnection of the coupling, when a predetermined force is imparted on the mechanism by a plunger carried by one of the actuators.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of the present invention coupling device showing both ball valve elements in an open flow position.
FIG. 2 is a top view of the present invention coupling device showing both ball valve elements in a zero-spill closed flow position.
FIG. 3 is an axial sectional view of the present invention coupling device showing both ball valve elements in an open flow position, as in FIG.1.
FIG. 4 is a radial sectional view along the plane 4--4 in FIG. 1.
FIG. 5 is a view of the toggle connected to the elongated rod along the plane 5--5 in FIG. 4.
FIG. 6 is an exploded isometric view of the toggle in connection with the elongated rod and a link member.
FIG. 7 is an axial sectional view of the ball valve elements both in an open flow position.
FIG. 8 is an axial sectional view of the ball valve elements in an ordinary operating condition closed flow position.
FIG. 9 is an axial sectional view of the ball valve elements in an emergency disconnect position.
FIG. 10 is an axial sectional view of the coupling disconnected under emergency disconnection conditions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. l, a coupling device (10) includes first and second fluid conduit ends (12, 14) for joining fluid conduits (16, 18) forming a fluid flow path. Each conduit end (12, 14) is shaped to house a ball or plug type valve element. In the embodiment shown, a ball valve (20, 22) having a tunnel-shaped passage (19) is used.
As shown in FIG. 3, each conduit end (12, 14) is provided with a mating collar (24, 26) designed to matingly fit in sealing contact with each other when the conduit ends are joined. The inner radial surface of each mating collar is configured to the contour of the valve element (20, 22) in order to form a seal. Elastomer seal elements (28, 30) can be provided to enhance sealing with the valve elements (20, 22). An additional elastomer seal element (32) can be provided between the mating collars (28, 30) to improve sealing. Each ball valve (20, 22) is rotatably received in the respective conduit end (12, 14). The first ball valve (20) has a concave recess (21) extending radially inward from its outer surface which is adapted to receive a portion of the convex outer surface of the other ball valve (22) when the conduit ends (12, 14) are joined. As will be discussed below, this feature is provided to prevent the trapping of fluid between the two ball valves (20, 22) prior to emergency disconnection. A lower spindle (34, 36) cooperating with bearing means (38, 40) is mounted at the lower end of each ball valve (20, 22) enabling rotation of each ball valve (20, 22) relative to the respective conduit end (12, 14). An upper spindle (38, 40) is connected to each ball valve (20, 22) by a key type connection (42, 44) which, in turn, is rotatably supported relative to the respective conduit end (12, 14). Additional sealing elements (46, 48, 50, 52) can be provided to seal between each upper spindle (38, 40) and the respective conduit end (12, 14).
As shown in FIG. 3, an extension shaft (54) extends from the second upper spindle (40) up into a drive housing (56). The extension shaft (54) is provided with a gear (58) for transmitting rotational force to open or close the second ball valve (22). The rotational force provided to the gear (58) is transmitted through a gear rack (60) which is fixed for translation with a plunger (62). The plunger (62) is fixed to a piston (64) and rod (66) which are housed in a closed cylinder (68) comprising a second actuator (70). The actuator (70) may be any suitable type, such as pneumatic or mechanical, for transmitting force linearly.
As shown in FIG. S 1-2, a latch (72) for locking the actuator (70) to prevent the plunger (62) and gear rack (60) from being activated is pivotally mounted on the second conduit end (14). A first end (74) of the latch (72) is configured to be received in a notch (76) on the gear rack (60). The second end (78) of the latch (72) carries a cam disc (80) for being contacted to cause the latch (72) to pivot such that the first end (74) moves out of engagement with the notch (76) to unlock the actuator (70).
A lever arm (82) is pivotally mounted on the first conduit end (12). The lever arm (82) has a beveled end (84) designed to contact the cam disc (80) to pivot latch (72). The lever arm (82) is pivoted by a first actuator (86). The actuator (86) may be any suitable type, such as pneumatic or mechanical, for transmitting force linearly. The actuator (86) comprises a cylindrical housing (87) and a piston (88) and rod (90) which move linearly upon activation. Near the end of the rod (90) is a pin (92) which cooperates with a slot (94) on a radially extending portion (96) of the lever arm (82) to cause the lever arm (82) to pivot in response to the linear movement on the piston (88) and rod (90).
A plurality of linked members (98, 100, 102, 104) for securing the two conduit ends (12, 14) together are shown in FIG. 4. A plurality of link elements (98) are pivotally linked to rods (100) by pins (106) or other suitable means, such that each rod (100) is adjacent to a link element (98) on each side. While the number of link elements (98) and rods (100) may vary, the present embodiment includes four link elements (98) and three rods (100). At a first end of the linked rods (100) and link elements (98) toggle means (104) comprising two plates (108), shown in FIG. 5, are pivotally linked at one end to a link member (98) by a pin (110) or other suitable means. At the other end of the linked rods (100) and link elements (98) an elongated rod (102) is pivotally linked at one end to a link element (98) by a pin (112) or other suitable means. The other end of each of the toggle means (104) and the elongated rod (102) are pivotally linked to each other by a pin (114) or other suitable means, such that the linked rods (100), link elements (98), elongated rod (102), and toggle means (104) form a closed loop. Mounted on the upper end of the elongated rod (102) is a cylindrical extension (116) having an impact surface (118). As shown in FIG. 6, each link element (98) comprises two plates (99), an integrally formed middle portion (101), and an inner circumferential groove (103) having beveled sides (105) adapted to fit over the beveled edges (25, 27) of the mating collars (24, 26) when the two mating collars (24, 26) are engaged with each other.
In order to lock the coupling device (10) over the joined conduit ends (12, 14) the mating collars (24, 26) are joined together as shown clearly in FIG. 3. The link elements (98) are positioned around the circumference of the mating collars (24, 26) such that the beveled edges (25, 27) of the mating collars (24, 26) are received in the grooves (103) of the link elements (98). Next, the elongated rod (102) is pivoted about the pin (112) that connects it to a link element (98) in a direction toward the link element (98) to which the toggle means (104) are connected. This pivoting of the elongated rod (102) causes the toggle means (104) to pivot about the pin (110) connecting it to a link element (98) in the same direction as the elongated rod (102). The pivoting of both the elongated rod (102) and the toggle means (104) causes the overall circumferential length of the linked members (98, 100, 102, 104) to be reduced, exerting compression on the outer circumference of the mating collars (24, 26). The compression exerted on the mating collars (24, 26) is redirected by the beveled surfaces (25, 27) in cooperation with the beveled portions (105) of the link element groove (103) such that the mating collars (24, 26) are pressed against each other in sealing contact. The toggle means (104) are pivoted to a position where a hole (125) in each plate (108) is aligned with a hole (107) in each plate (99) of the link element (98). A shear pin (109) is inserted through the holes (125, 107) in order to lock the toggle means (104) to the link element (98). In this position, the coupling device (10) is locked and the conduit ends (12, 14 ) are joined.
To regulate fluid flow under normal operating conditions, the ball valves (20, 22) are positioned as shown in FIG. S 7-8. FIG. 7 shows both ball valves (20, 22) in the open position to allow fluid flow. FIG. 8 shows the stop flow position under normal conditions, whereby the first ball valve 20 is closed and the second ball valve (22) remains opened.
In an emergency situation when it is desired to quickly disconnect the coupling, both ball valves (20, 22) are turned to a closed position as shown in FIG. 9 so that the concave recess (21) of the first ball valve (20) receives the outer convex surface of the second ball valve (22) in order to prevent fluid from being trapped between the ball valves (20, 22). The cooperation of the second actuator (70) and the linked members (98, 100, 102, 104) prevents release of the linked members (98, 100, 102, 104) prior to closing of both ball valves (20, 22).
To execute emergency decoupling, the first actuator (86) is activated, causing the piston (88) and rod (90) to advance linearly. The linear movement of the rod (90) causes the pin (92) to move within the slot (94) of the extending portion (96) of the lever arm (82), causing the lever arm (82) and the upper spindle (38) and first ball valve (20) to pivot. Upon full extension of the piston (88) and rod (90), the first ball valve (20) is pivoted to a fully closed position and the lever arm (82) is pivoted to contact and release the latch (72) as shown in FIG. 2. When the latch (72) is released, the second actuator (70) is activated causing the piston (64) and rod (66) to advance linearly. The linear movement of the rod (66) causes the gear rack (60) and plunger (62) to advance. The gear rack (60) causes rotation of the gear (58) with which it is engaged, causing the upper spindle (40) and second ball valve (22) to pivot until the ball valve (22) is in a fully closed position, as shown in FIG. 9. As the ball valve (22) reaches the fully opened position, the plunger (62) contacts the impact surface (118), as shown in FIG. 2. The force exerted on the impact surface (118) by the plunger (62) causes the elongated rod (102) to pivot about pin (112)in a direction away from the toggle means (104) such that the shear pin (109) is stressed, causing it to shear. Once the shear pin (109) is sheared, the elongated rod continues to pivot about the pin (112) and the toggle means (104) pivot about the pin (110), increasing the effective circumferential length of the linked members (98, 100, 102, 104). The increase circumferential length of the linked members (98, 100, 102, 104) releases the pressure on the mating collars (24, 26) such that the conduit ends (12, 14) may be separated as shown in FIG. 10.
Although the best mode contemplated for carrying out the present invention has been herein shown and described, it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention. | An improved double ball valve powered emergency release coupling includes two fluid-carrying conduits, each having a ball or plug valve received therein, which are prevented from being decoupled unless both ball or plug valves are moved to a closed position prior to decoupling. The improved coupling prevents inadvertent spilling during decoupling. A mechanical or hydraulic actuator corresponding to each valve element is provided for sequentially rotating each valve element between opened and closed positions. | 5 |
BACKGROUND OF INVENTION
[0001] The present invention relates to a novel thermostable DNA polymerase I from Rhodothermus obamensis , which possesses 3′-5′ exonuclease activity and has a preliminary estimated half-life of 35 minutes at 94° C., as well as methods for cloning and producing the large fragment of R. obamensis DNA polymerase I, as well as isolated DNA encoding this enzyme and vectors containing the same.
[0002] DNA polymerases are important enzymes involved in chromosome replication and repair. These enzymes have also been employed in DNA diagnostics and analysis. In several of these applications, including PCR, thermocycle sequencing, and iso-thermal strand displacement amplification, DNA polymerases must maintain enzymatic activity at temperatures from 50° C.-95° C. One advantageous source for such polymerases is thermophiles. Here we describe a method for purifying, cloning and expressing Rhodothermus obamensis DNA polymerase I large fragment in E. coli.
[0003] [0003] E. coli DNA polymerase I and T4 DNA polymerase were cloned, purified and characterized previously (Joyce C. M. and Derbyshire V. Methods in Enzymology , 262:3-13, (1995); Nossal N. G. et al. Methods in Enzymology , 262: 560-569, (1995)). These enzymes have a variety of uses in recombinant DNA technology including DNA labeling by nick translation, second-strand cDNA synthesis in cDNA cloning, and DNA sequencing.
[0004] U.S. Pat. Nos. 4,683,195, 4,683,202 and 4,800,159 disclosed the use of DNA polymerases in a process for amplifying, detecting, and/or cloning nucleic acid sequences. This process, commonly referred to as polymerase chain reaction (PCR), involves the use of a polymerase, primers and nucleotide triphosphates and amplifying existing nucleic acid sequences.
[0005] A number of thermostable DNA polymerases have been isolated and cloned from thermophilic eubacteria. The thermostable Bst DNA polymerase from Bacillus stearothermophilus and the Bca DNA polymerase from Bacillus caldotenax have been cloned and expressed in E. coli (Aliotta J. M. et al. Genetic Analysis: Biomol. Engin , 12:185-195, (1996); Uemori, T. et al. J. Biochem . 113:401-410, (1993)). These two DNA polymerases have been used in strand displacement amplification (Milla, M. A. et al. Biotechniques , 24:392-395, (1998)).
[0006] DNA polymerases have also been cloned from a number of Thermus species such as T. aquaticus (Lawyer, F. C., et al. J. Biol. Chem . 264:6427-6437 (1989)). T. thermophilus (Asakura, K. et al. J. Ferment. Bioeng ., 76:265-269, (1993), and T. filiformis (Jung, S. E. et al. GenBank Accession No. AF030320, (1997)). These characterized Thermus-DNA polymerases, belonging to the Family A DNA polymerases, exhibit 5′-3′ exonuclease activity while lacking 3′-5′ proof-reading exonuclease activity. For thermocycling sequencing, a Taq DNA polymerase variant called ThermoSequenase (F667Y) has been constructed that efficiently incorporates dideoxy terminators and dye-terminators (Tabor S. and Richardson C. C., Proc. Natl. Acad. Sci. USA , 92:6339-6343, (1995); Vander Horn P. B. et al. Biotechniques , 22:758-765, (1996)). Although readable DNA sequence for one sequencing reaction has improved from 300 bp to about 600 bp, further technical improvements are needed to achieve 1000 or more bases of reliable sequence for each reaction. Such improvement most likely requires the introduction of new DNA polymerases such as thermostable T7-like DNA polymerases.
[0007] Research was conducted on the isolation and purification of DNA polymerases from Thermus aquaticus (Chien, A. et al. J. Bacteriol . 127:1550-1557, (1976)). The publication of Chien, A. et al. discloses the isolation and purification of a DNA polymerase with a temperature optimum of 80° C. from T. aquaticus YT1 strain. The Chien et al., purification procedure involves a four-step process. These steps include preparation of crude extract, DEAE-Sephadex chromatography, phosphocellulose chromatography and chromatography on DNA cellulose.
[0008] U.S. Pat. No. 4,889,818 discloses a purified thermostable DNA polymerase from T. aquaticus , Taq DNA polymerase, having a molecular weight of about 86,000 to 90,000 daltons prepared by a process substantially identical to the process of Kaledin with the addition of the substitution of a phosphocellulose chromatography step in lieu of chromatography on single-strand DNA-cellulose. In addition, European Patent Application 0258017 disclose Taq polymerase as the preferred enzyme for use in the PCR process discussed above. Research has indicated that while the Taq DNA polymerase has a 5′-3′ polymerase-dependent exonuclease function, Taq DNA polymerase does not possess a 3′-5′ proofreading exonuclease function (Lawyer, F. C., et al. J. Biol. Chem. 264:6427-6437 (1989)). As a result, Taq DNA polymerase is prone to base incorporation errors, making its use in certain applications undesirable. For example, attempting to clone an amplified gene is problematic since any one copy of the gene may contain an error due to a random misincorporation event. Depending on where in the replication cycle that error occurs (e.g., in an early replication cycle), the entire DNA amplified could contain the erroneously incorporated base, thus, giving rise to a mutated gene product.
[0009] Accordingly, it would be desirable to clone and produce a thermostable DNA polymerase with 3′-5′ proof-reading exonuclease activity that may be used to improve the fidelity of DNA amplification reactions described above. It would also be desirable to clone a thermostable and processive DNA polymerase which efficiently incorporates dye terminators.
SUMMARY OF THE INVENTION
[0010] In accordance with the present invention, there is provided a novel thermostable DNA polymerase I from Rhodothermus obamensis , which possesses 3′-5′ exonuclease activity and has a preliminarily estimated half-life of 35 minutes at 94° C. This thermostable enzyme obtainable from Rhodothermus obamensis , a thermophile isolated from a shallow marine hydrothermal vent in Tachibana Bay, Japan, has a molecular weight of about 104 kDa, and possesses a tyrosine residue in the ribosome binding domain which increases the incorporation rate of dideoxynucleotides.
[0011] Also provided by the instant invention are methods for cloning and producing the large fragment of R. obamensis DNA polymerase I, as well as isolated DNA encoding this enzyme and vectors containing the same. The Rhodothermus obamensis DNA polymerase I large fragment has a molecular weight of about 71 kDa.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 is the nucleotide sequence (SEQ ID NO:1) and the predicted amino acid sequences (SEQ ID NO:2) of R. obamensis DNA polymerase I.
[0013] [0013]FIG. 2 is the nucleotide sequence (SEQ ID NO:3) and the predicted amino acid sequences (SEQ ID NO:4) of R. obamensis DNA polymerase I large fragment.
[0014] [0014]FIG. 3 is the SDS-PAGE gel showing the purification steps for recombinant R. obamensis DNA polymerase I large fragment. Lane 1 and 3, IPTG-induced cell extract after heat treatment; lane 2 and 4, non-induced cell extract after heat treatment; lane 5 and 7, protein size marker (7 to 212 kDa); lane 6, partially purified recombinant R. obamensis DNA polymerase I large fragment. Arrow I, indicating recombinant R. obamensis DNA polymerase I large fragment; arrow II indicating E. coli GroEL protein.
[0015] [0015]FIG. 4 illustrates the thermostability of the recombinant R. obamensis DNA polymerase I large fragment at 94° C. The polymerase assay was carried out at 65° C. for 20 min after incubation of the DNA polymerase at 94° C. for 1 to 40 min.
DETAILED DESCRIPTION OF THE INVENTION
[0016] [0016] Rhodothermus obamensis was isolated from a shallow marine hydrothermal vent in Tachibana Bay, Japan. It can grow in the temperature range of 50 to 85° C. with optimal growth temperature at 80° C. The pH range for growth media is pH 5.5 to 9.0. It can be cultured in a marine broth with NaCl concentration of 1 to 5%. In a preferred embodiment, the type strain is Rhodothermus obamensis OKD7 (Sako Y. et al. Int. J. Syst. Bactriol. 46:1099-1104, (1996)).
[0017] Purification of R. Obamensis DNA Polymerase I
[0018] The native or recombinant R. obamensis DNA polymerase can be purified by the following procedure:
[0019] Cells are resuspended in a lysis buffer (50 mM Tris-HCl, pH 8, 1 mM EDTA, 5 mM DTT) and lysed by sonication. Pulverized ammonium sulfate is added slowly with gentle stirring to a final concentration of 30% (W/V), and the suspension is allowed to sit at 40° C. overnight. The ammonium sulfate precipitate is collected by centrifugation in a rotor at 12,000 rpm for 30 min. The supernatant is discarded. The pellet is resuspended in a buffer containing 50 mM Tris-HCl, pH 8, 10% glycerol, 1 mM EDTA, 5 mM DTT. The R. obamensis DNA polymerase I may be further purified by chromatography, for example:
[0020] [0020] R. obamensis DNA polymerase I may be purified by phosphocellulose chromatography (Whatman cellulose phosphate ion-exchange resin P11). Fractions may be assayed for thermostable DNA polymerase activity and peak fractions may be pooled and dialysed.
[0021] [0021] R. obamensis DNA polymerase I may be purified by DEAE chromatography (Whatman ion exchange cellulose DE52 resin). Fractions may then be assayed for thermostable DNA polymerase activity and peak fractions can be pooled and dialysed.
[0022] [0022] R. obamensis DNA polymerase I may be purified, as in a preferred embodiment, by DNA binding affinity column chromatography (Heparin sepharose or Heparin TSK). Fractions may be assayed for thermostable DNA polymerase activity, and peak fractions may be pooled and dialysed.
[0023] [0023] R. obamensis DNA polymerase I can be purified by Mono Q FPLC. Fractions may be assayed for thermostable DNA polymerase activity. Peak fractions may be pooled and dialysed.
[0024] [0024] R. obamensis DNA polymerase I may be further purified by Mono S FPLC. Fractions may then be assayed for thermostable DNA polymerase activity, and peak fractions can be pooled and dialysed in a storage buffer with 50% glycerol.
[0025] Alternatively, recombinant R. obamensis DNA polymerase I may be purified by affinity purification via the use of a fusion protein. For example, fusion of R. obamensis DNA polymerase I to maltose binding protein, chitin binding protein, GST, or His tag. After the fusion protein is purified, the affinity tag may be removed by a protease or by controlled protein splicing/cleavage reaction. (U.S. Pat. Nos. 5,643,758 and 5,834,247.)
[0026] Cloning of R. Obamensis DNA Polymerase I
[0027] The method described herein by which the R. obamensis DNA polymerase I gene is cloned and its large fragment is expressed includes the following steps:
[0028] 1. The genomic DNA is purified from R. obamensis cells.
[0029] 2. Conserved regions in DNA polymerase I are found by nucleotide sequence comparison of Pol I type DNA polymerases from Eubacteria and especially thermophilic bacteria. Based on the conserved sequences, one set of degenerate primers is designed and an initial PCR is carried out using the degenerate primers to amplify part of the R. obamensis DNA polymerase I. A 609 bp DNA fragment in the DNA polymerase domain is amplified and sequenced.
[0030] 3. Single stranded DNA primers are designed based on the initial 609 bp sequence. Inverse PCR is used to amplify upstream and downstream DNA sequences. R. obamensis genomic DNA is digested with restriction enzymes with 4-6 bp recognition sequences, giving rise to reasonable size template DNA for inverse PCR reactions. The digested DNA is self-ligated at a low DNA concentration. The ligated circular DNA is used as templates for inverse PCR reaction using a set of primers that annealed to the left or right ends of the initial fragment. The inverse PCR products are purified in low-melting agarose gel and sequenced directly using primers. The newly derived DNA sequences are compared with sequences in GenBank using BlastX program. This step is repeated until the start codon was found upstream and stop codon was found downstream. The entire DNA polymerase gene is found to be 2772 bp long, encoding a protein with predicted molecular weight of 104.7 kDa.
[0031] 4. The 3′-5′ exonuclease domain is compared with that of E. coli DNA polymerase I. It is found that R. obamensis DNA polymerase I contains three conserved motifs of 3′-5′ exonuclease. The three conserved motifs have the following amino acid sequence: motif I, DTE, motif II, NLKYD, motif III, YACED. It is concluded that R. obamensis DNA polymerase I may contain 3′-5′ exonuclease proofreading activity. In addition, R. obamensis DNA polymerase I contains a Tyr residue (Y761) in the ribose binding region ( E. coli O helix homolog). It's known that Tyr residue at this position increases the incorporation rate for dideoxynucleotides.
[0032] 5. To overexpress the large fragment of R. obamensis DNA polymerase I, 888-bp DNA encoding N-terminus 5′-3′ exonuclease domain is deleted by PCR. The deletion variant lacking 5′-3′ exonuclease region is 1884 bp long, encoding the 628-aa DNA polymerase I large fragment with predicted molecular weight of 71.3 kDa. This R. obamensis DNA polymerase I large fragment is similar to E. coli Klenow fragment, but it contains 28 extra amino acid residues at the N-terminus. The DNA coding for the large fragment is amplified by PCR, digested with NdeI and BamHI and cloned into a T7 expression vector pAII17. One clone #7 is further characterized.
[0033] 6 . E. coli cells ER2566 [pAII17-Rob polI large fragment] is cultured to late log phase and induced by addition of IPTG ( R. obamensis is abbreviated as Rob). Cell extract is prepared and heated at 65° C. for 30 min. Heat-denatured E. coli proteins were removed by centrifugation and the supernatant is assayed at 65° C. for DNA polymerase activity on activated calf thymus DNA. It is found that the large fragment has thermostable DNA polymerase activity.
[0034] 7 . R. obamensis DNA polymerase I large fragment is purified by chromatography through Heparin-Sepharose column. The large fragment is partially purified. Another protein of 60 kDa is copurified with R. obamensis DNA polymerase I large fragment. To determine if this 60 kDa protein is a protease degradation product, the N-terminus of the 60 kDa protein is sequenced. The first 15 residues are compared with known proteins in protein data base. It has 100% identity to E. coli GroEL protein.
[0035] 8. To determine the half-life of the partially purified large fragment, the protein is heated at 94° C. for 1 to 40 min. Samples are taken and assayed for remaining DNA polymerase activity. It is found that R. obamensis DNA polymerase I large fragment has an half-life of 35 min at 94° C.
[0036] The following Examples are given to illustrate embodiments of the present invention as it is presently preferred to practice. It will be understood that these Examples are illustrative, and that the invention is not to be considered as restricted thereto as indicated in the appended claims.
[0037] The references cited above and below are herein incorporated by reference.
EXAMPLE I
Cloning of R. obamensis DNA Polymerase I Gene
[0038] [0038] Rhodothermus obamensis (JCM 9785, Japan Collection of Microorganisms, Wako-shi, Saitama, Japan) was cultured in Bacto marine broth at 70° C. overnight. Cells from one liter of culture were collected by centrifugation. Genomic DNA was prepared from the cell pellet by the standard procedure. A set of degenerate primers were designed based on the conserved amino acid sequence in the DNA polymerase domain. The primers have the following sequences:
(SEQ ID NO:5) 5′-TCCGA(C/T)CCCAACCT(G/C)CAGAACATCCC-3′ 138-151 (SEQ ID NO:6) 5′-AGGA(G/C) (G/C)AGCTCGTCGTG(G/C)ACCTG-3′ 138-152
[0039] (G/C) indicates degenerate position, G or C.
[0040] Primers 138-151 and 138-152 were used to amplify a portion of R. obamensis DNA polymerase I in PCR under the following condition: 95° C. for 30 sec, 50° C. for 1 min, 72° C. for 1 min, 35 cycles, 2.5 units of Taq plus Vent® DNA polymerase (50:1 ratio). A ˜600 bp PCR product was found. The PCR product was gel-purified in low-melting agarose gel and sequenced directly by thermocycling sequencing using primer 138-151 which generated a 609 bp DNA fragment. When this DNA fragment was translated into amino acid sequence and compared to known proteins in GenBank, it was found that it has 50% aa sequence identity to E. coli DNA polymerase I (pol I) and 54% aa sequence identity to Taq DNA polymerase.
[0041] Two primers were synthesized based on the known 609 bp DNA sequence. They have the following sequences:
5′-CGCAGGGCGTTTGTGCCGCGG-3′ 202-154 (SEQ ID NO:7) 5′-GTCTCCCGCCCCATCTCGGTG-3′ 202-155 (SEQ ID NO:8)
[0042] [0042] R. obamensis genomic DNA was digested individually with the following restriction enzymes: AvaI, BsaAI, BsaHI, BstNI, EagI, HaeII, HhaI, HincII, MspI, NcoI, NspI, SacII, Sau3AI, TaqI, TseI, Tsp45I, BanI, or AluI. After restriction digestion, the DNA was purified by phenol-CHCl 3 extraction and ethanol precipitation. The digested DNA was self-ligated at a low DNA concentration (2 ug/ml). T4 DNA ligase was inactivated by heating at 65° C. for 30 min and the DNA was precipitated and resuspended in TE buffer. The self-ligated genomic DNA was used in inverse PCR to amplify the remaining portion of the DNA polymerase I gene. The following condition was used in inverse PCR: 95° C. for 30 sec, 55° C. for 30 sec, and 72° C. for 2 min, 30 cycles. Inverse PCR products were found in BsaHI, HaelI, NcoI, and NspI digested and self-ligated DNA templates. The NcoI inverse PCR fragment was the largest, giving rise to about 1950 bp of new DNA sequence (2550 bp−600 bp=˜1950 bp). This fragment was gel-purified in low-melting agarose gel and sequenced directly using primers 202-154 and 202-155. Four new primers were made to finish sequencing the NcoI fragment.
[0043] Two new inverse PCR primers were made to amplify the DNA beyond the NcoI site. The two primers have the following sequences:
5′-GCCGGCCGCTTGTCAACTCGA-3′ 205-7 (SEQ ID NO:9) 5′-TGATGAACACGTATTGCGCCC-3′ 205-8 (SEQ ID NO:10)
[0044] [0044] R. obamensis genomic DNA was digested with restriction enzymes AvaI, BsaHI, BstNI, SacII, Sau3AI, TaqI, TseI, Tsp45I, BanI, AluI and self-ligated as described above. The ligated genomic DNA was used in inverse PCR. Inverse PCR condition was 95° C. for 30 sec, 55° C. for 30 sec, and 72° C. for 2 min, 35 cycles. Inverse PCR products were found in Sau3AI, TaqI, and TseI digested and self-ligated DNA. The inverse PCR products were gel-purified and sequenced which gave rise to 27 bp of new DNA sequence. A start codon was found in the newly derived sequence.
[0045] To amplify the C-terminus coding region of R. obamensis DNA polymerase I, two inverse PCR primers were made:
(SEQ ID NO:11) 5′-GAAGCGGGAAGGCTACCGGGCCAA-3′ 204-7 (SEQ ID NO:12) 5′-AGTCGGTGGTAGATGTGCACCATG-3′ 204-8
[0046] Inverse PCR condition was 95° C. for 30 sec, 55° C. for 30 sec. and 72° C. for 2 min, 35 cycles. Inverse PCR products were found in HaeII, NspI, Sau3AI, and Tsp45I digested and self-ligated templates. The inverse PCR products were gel-purified and sequenced which gave rise to the C-terminus coding region. The entire R. obamensis DNA polymerase gene is 2772 bp long, encoding a protein with predicted molecular weight of 104.7 kDa (FIG. 1). Unlike Taq DNA polymerase, R. obamensis DNA polymerase I contains three conserved 3′-5′ exonuclease motifs. The three conserved motifs have the following amino acid sequence:
[0047] motif I, DTE
[0048] motif II, NLKYD
[0049] motif III, YACED.
[0050] It is concluded that R. obamensis DNA polymerase I may contain 3′-5′ exonuclease proofreading activity. In addition, R. obamensis DNA polymerase I contains a Tyr residue (Y761) in the ribose binding region ( E. coli O helix homolog). It's known that Tyr residue at this position increases the incorporation rate for dideoxynucleotides. Pol I-like DNA polymerases that have a Tyr residue at the ribose selectivity site include DNA polymerases from phage T7 and T3, yeast mitochondria, Mycobacterium tuberculosis, Mycobacterium leprae, Rhodothermus obamensis , and Rhodothermus sp. ‘ITI518’.
EXAMPLE II
Expression of R. obamensis DNA Polymerase I Large Fragment
[0051] To construct a large fragment of R. obamensis DNA polymerase I, 888-bp DNA encoding N-terminus 5′-3′ exonuclease domain was deleted. The deletion variant lacking 5′-3′ exonuclease region is 1884 bp long, encoding 628-aa DNA polymerase I large fragment with predicted molecular weight of 71.3 kDa. This R. obamensis DNA polymerase I large fragment is similar to E. coli Klenow fragment, but it contains 28 extra amino acid residues at the N-terminus (FIG. 2). The DNA coding for the large fragment was amplified by PCR under the PCR condition of 95° C. for 30 sec, 55° C. for 30 sec. and 72° C. for 2 min, 20 cycles, 2 units of Vent® DNA polymerase. The PCR primers have the following sequence:
5′-CTGGCCGGC CATATG AACGGCGAAGCCGCCTTGGATGAG-3′ 204-146. ( CATATG = Nde I site). (SEQ ID NO:13) 5′-GTT GGATCC GCTTCAGTGGGCATCCAGCCAGTTGTC-3′ 204-147. ( GGATCC = Bam HI site). (SEQ ID NO:14)
[0052] The amplified PCR product was digested with NdeI and BamHI and inserted into a T7 expression vector pAII17 precut with NdeI and BamHI. The ligated DNA was used to transform E. coli competent cell ER2566. Eighteen Amp R transformants were screened for insert. Six plasmids contained the correct size insert (#2, #5, #6, #7, #12, and #14). To test DNA polymerase activity in all six isolates, E. coli cells ER2566 [pAII17-Rob-polI-large fragment] were cultured to late log phase and induced by addition of IPTG to 0.5 mM concentration ( R. obamensis is abbreviated as Rob). Cell extract was prepared by sonication and centrifugation. The cleared lysate was heated at 65° C. for 30 min. Heat-denatured E. coli proteins were removed by centrifugation and the supernatant was analyzed on an SDS-PAGE gel (FIG. 3, lanes 1-4) and was assayed at 65° C. for DNA polymerase activity on activated calf thymus DNA. The DNA polymerase activity was performed in a total of 50 ul volume at 65° C. It contains 20 ul of cell extract, 5 ul (10 ug) of activated calf thymus DNA, 1 ul of dNTP (5.4 mM), 5 ul of 10× thermopol buffer, 1 ul of [ 3 H]TTP, 18 ul of sdH 2 O. The components of 1× Thermopol buffer are 10 mM KCl, 20 mM Tris-HCl, pH 8.8, 10 mM (NH 4 ) 2 SO 4 471 , 2 mM MgSO 4 , 0.1% Triton X-100. Following incubation at 65° C. for 20-30 min, the entire volume was spotted on to DE81 membrane discs and dried under a heating lamp for 30 min. The membranes were washed 2× in 500 ml of 10% TCA. The acid-insoluble [ 3 H]TMP incorporated DNA was counted in scintillation counting solution. It was found that isolates #2, #5, #7, #12, and #14 have thermostable DNA polymerase activity. #7 and #12 displayed highest activity. #7 was chosen to be further characterized. Two liters of cells of #7 clone were induced with IPTG and cell extract was prepared by sonication and centrifugation. The cell extract was heated at 65° C. for 30 min and the denatured E. coli proteins were removed by centrifugation. R. obamensis DNA polymerase I large fragment was purified by chromatography through Heparin-Sepharose column. R. obamensis DNA polymerase I large fragment was eluted with 50 mM to 1 M NaCl gradient. Fractions 19 and 20 contained the most DNA polymerase activity. Proteins from fractions 15 to 20 were analyzed on an SDS-PAG gel. Two major proteins were found, one with expected size of 71 kDa. Another protein of 60 kDa is copurified with R. obamensis DNA polymerase I large fragment (FIG. 3, lane 6). To determine if this 60 kDa protein was a protease degradation product, the N-terminus of the 60 kDa protein was sequenced. The first 15 residues (AAKDVKFGNDARVKM (SEQ ID NO:15)) are compared with protein data base. It has 100% identity to E. coli GroEL protein. It was concluded that the 60 kDa protein is not a protease degradation product. Since R. obamensis DNA polymerase I large fragment is a foreign protein to E. coli , perhaps it needs more GroEL protein to help it to fold correctly.
[0053] To increase stability of the T7 expression clone, ER2566[pLysS] was transformed with the plasmid carrying Rob polI large fragment. The final expression strain is ER2566[pAII17-Rob polI large fragment, pLysS], Amp R and Cm R .
[0054] A sample of the E. coli containing ER2566[pAII17-Rob polI large fragment, pLysS], (NEB#1186) has been deposited under the terms and conditions of the Budapest Treaty with the American Type Culture Collection on Mar. ______, 1999 and received ATCC Accession No. ______.
[0055] To determine the half-life of the partially purified large fragment, the protein is heated at 94° C. for 1 to 40 min. Samples are taken and assayed for remaining DNA polymerase activity. DNA polymerase assay was about the same as described above except that 5 ul of the heat-treated large fragment was used in the assay. The time of heat treatment was plotted against the percentage of remaining DNA polymerase activity. It was found that R. obamensis DNA polymerase I large fragment has an half-life of 35 min at 94° C. (FIG. 4).
[0056] During the course of this work, the DNA polymerase I gene was cloned from Rhodothermus sp. ‘ITI518’ and was released in GenBank on Jan. 1, 1999 (Blondal et al., GenBank Accession No. AF028719). Rhodothermus obamensis and Rhodothermus sp. ‘ITI518’ DNA polymerase I share 98% amino acid sequence identity. However, the thermostability of Rhodothermus obamensis and Rhodothermus sp. ‘ITI518’ DNA polymerase I large fragments are different. It was reported that the half-life of Rhodothermus sp. ‘ITI518’ DNA polymerase I large fragment at 90° C. is about 10 min (Blondal, T. et al. International Conference: Thermophile 98, Abstract, page G-P20). R. obamensis DNA polymerase I large fragment is more thermostable. It has an half-life of 35 min at 94° C. There are two possible explanations. One possibility is that R. obamensis DNA polymerase I large fragment has a different N-terminus than Rhodothermus sp. ‘ITI518’ DNA polymerase I large fragment (due to different aa deletion in the 5′-3′ exonuclease region). It's known that N-terminus deletion of 5′-3′ exonuclease domain can increase thermostability of DNA polymerases. The second possibility is that R. obamensis DNA polymerase I large fragment fortuitously copurified with E. coli protein GroEL, which is a chaperon for protein folding. The inclusion of GroEL protein in the polymerase assay may increase the thermostability of R. obamensis DNA polymerase I large fragment at 94° C.
EXAMPLE III
Expression of R. obamensis DNA Polymerase I and its Large Fragment in any Expression Host
[0057] [0057] R. obamensis DNA polymerase I gene or its deletion derivative can be amplified by PCR using primers. The deletion can be in the 5′-3′ or 3′-5′ exonuclease domains. Alternatively, the active site residues of 5′-3′ or 3′-5′ exonuclease domains can mutagenized without affecting the DNA polymerase domain. Restriction sites can be engineered in the PCR primers to aid the cloning of the PCR products into appropriate cloning vectors. PCR conditions can be 90-95° C. for 30 sec, 50-65° C. for 30 sec. and 72° C. for 1-3 min, 20-30 cycles, 1-5 units of Vent® DNA polymerase or any proofreading DNA polymerase. PCR products can be digested with appropriate restriction enzymes. After ligation of PCR products to vectors, the ligated DNA can be used to transform expression host by transformation or electroporation. Plasmid mini-preparations can be made to screen inserts. Once the correct inserts are found, cells can be induced to produce the desired proteins. Cell extract can be prepared by lysozyme treatment or sonication and centrifugation. The cleared lysate can be heated at 65-85° C. for 30-60 min. Heat-denatured E. coli proteins can be removed by centrifugation and the supernatant can be analyzed on an SDS-PAG gel. The lysate can be assayed at 65-85° C. for DNA polymerase activity on activated calf thymus DNA or single-stranded DNA with a primer. The DNA polymerase activity can be , performed in a total of 50-100 ul volume at 65-85° C. It contains 1-20 ul of cell extract, 5 ul (10 ug) of activated calf thymus DNA, 1 ul of dNTP (5.4 mM), 5 ul of 10× thermopol buffer or any DNA polymerase buffer, 1 ul of [ 3 H]TTP, 18 ul of sdH 2 O. The components of 1× Thermopol buffer are 10 mM KCl, 20 mM Tris-HCl, pH 8.8, 10 mM (NH 4 ) 2 SO 4 , 2 mM MgSO 4 , 0.1% Triton X-100. Following incubation at 65-85° C. for 10-30 min, the entire volume can be spotted on to DE81 membrane discs and dried. The membranes can be washed 1-2× in 500 ml of 10% TCA. The acid-insoluble [ 3 H]TMP incorporated DNA can be counted in scintillation counting solution. R. obamensis DNA polymerase I and its large fragments can be purified by chromatography through affinity column, cation/anion exchange columns, or gel filtration columns.
[0058] To determine the half-life of the partially purified large fragment, the protein can be heated at 94° C. for 1 to 60 min. Samples can be taken and assayed for remaining DNA polymerase activity. The time course can be plotted against the percentage of remaining DNA polymerase activity. Heat shock proteins such as GroEL chaperon can be added to the polymerase reaction to increase the thermostability of DNA polymerase.
1
15
1
2775
DNA
Rhodothermus obamensis
CDS
(1)..(2772)
1
atg cag cgc ctg tac ctg atc gat gcc atg gcg ctg gcc tat cgg gcg 48
Met Gln Arg Leu Tyr Leu Ile Asp Ala Met Ala Leu Ala Tyr Arg Ala
1 5 10 15
caa tac gtg ttc atc agc cgg ccg ctt gtc aac tcg aag gga cag aac 96
Gln Tyr Val Phe Ile Ser Arg Pro Leu Val Asn Ser Lys Gly Gln Asn
20 25 30
acc tcg gcc gcc tac ggt ttt acg acc tcc ctt ctg aag ctg atc gaa 144
Thr Ser Ala Ala Tyr Gly Phe Thr Thr Ser Leu Leu Lys Leu Ile Glu
35 40 45
gaa cac ggc atg gac tac atg gcc gtg gtc ttc gac gcc ggc ggg gag 192
Glu His Gly Met Asp Tyr Met Ala Val Val Phe Asp Ala Gly Gly Glu
50 55 60
gag ggc acg ttt cgc gaa gcg atc tat gag gaa tac aag gcg cat cgg 240
Glu Gly Thr Phe Arg Glu Ala Ile Tyr Glu Glu Tyr Lys Ala His Arg
65 70 75 80
gag ccg ccg ccg gaa gat ctg ctg gcc aac ctg ccc tgg atc aag gag 288
Glu Pro Pro Pro Glu Asp Leu Leu Ala Asn Leu Pro Trp Ile Lys Glu
85 90 95
atc gtc cgg gcg ctg gac att ccc gtc atc gag gag ccg ggc gtc gag 336
Ile Val Arg Ala Leu Asp Ile Pro Val Ile Glu Glu Pro Gly Val Glu
100 105 110
gcc gac gac gtg atc gga acg ctg gcc cgt cgg gcc gag gcg cac ggc 384
Ala Asp Asp Val Ile Gly Thr Leu Ala Arg Arg Ala Glu Ala His Gly
115 120 125
atc gac gtg gtg atc gtc tca ccc gac aag gac ttt ctg cag ctg ctg 432
Ile Asp Val Val Ile Val Ser Pro Asp Lys Asp Phe Leu Gln Leu Leu
130 135 140
agc ccg cac gtt tcc atc tac aaa ccg gcg cgg cgc ggc gaa acc ttc 480
Ser Pro His Val Ser Ile Tyr Lys Pro Ala Arg Arg Gly Glu Thr Phe
145 150 155 160
gac ctg atc acc atc gag act ttc cgg gag acc tac ggc ctg gag ccg 528
Asp Leu Ile Thr Ile Glu Thr Phe Arg Glu Thr Tyr Gly Leu Glu Pro
165 170 175
cac cag ttc atc gac gtg ctg gct ctc atg ggc gat ccg agc gac aat 576
His Gln Phe Ile Asp Val Leu Ala Leu Met Gly Asp Pro Ser Asp Asn
180 185 190
gtg ccg ggc gtg ccg ggc atc ggc gaa aag acc gcc gtg cag ctc atc 624
Val Pro Gly Val Pro Gly Ile Gly Glu Lys Thr Ala Val Gln Leu Ile
195 200 205
caa cag tac ggc tcg gtg gaa aac ctg ctg gcc cat gcc gag gag gtg 672
Gln Gln Tyr Gly Ser Val Glu Asn Leu Leu Ala His Ala Glu Glu Val
210 215 220
aaa ggg aag cgg gcc cgc gag ggg ctc ctg aac cac cgc gag gaa gcg 720
Lys Gly Lys Arg Ala Arg Glu Gly Leu Leu Asn His Arg Glu Glu Ala
225 230 235 240
ctc ctc tcg aag cgg ctg gtg acg atc cgg acc gat gtg ccg ttg cgc 768
Leu Leu Ser Lys Arg Leu Val Thr Ile Arg Thr Asp Val Pro Leu Arg
245 250 255
att cgc tgg gag gcg ttc cat cgc gcc cgg ccc gat ctg ccg cgc ctg 816
Ile Arg Trp Glu Ala Phe His Arg Ala Arg Pro Asp Leu Pro Arg Leu
260 265 270
ctg cag atc ttt cag gag ctg gaa ttc gac tcg ctg gtg cgg cgc atc 864
Leu Gln Ile Phe Gln Glu Leu Glu Phe Asp Ser Leu Val Arg Arg Ile
275 280 285
cgg gaa ggc gga ctg gcc ggc att gtg aac ggc gaa gcc gcc ttg gat 912
Arg Glu Gly Gly Leu Ala Gly Ile Val Asn Gly Glu Ala Ala Leu Asp
290 295 300
gag gcg ctt gaa gcg gag acc gag ccg gag ttc gat ttc ggg cca tac 960
Glu Ala Leu Glu Ala Glu Thr Glu Pro Glu Phe Asp Phe Gly Pro Tyr
305 310 315 320
gag ccg ctg cag gtg tac gat ccg gaa aag gcg gac tac cgg atc gtc 1008
Glu Pro Leu Gln Val Tyr Asp Pro Glu Lys Ala Asp Tyr Arg Ile Val
325 330 335
cgc aac cgc cag cag ctc gac gaa ctc gtg gcg cat ctg gac gga ttc 1056
Arg Asn Arg Gln Gln Leu Asp Glu Leu Val Ala His Leu Asp Gly Phe
340 345 350
gaa cgg ctg gcc atc gac acg gag acg act tcg acc gag gcc atg tgg 1104
Glu Arg Leu Ala Ile Asp Thr Glu Thr Thr Ser Thr Glu Ala Met Trp
355 360 365
gcc tcg ctg gtg ggc att gcc ttt tcc tgg gag aaa ggc cag ggc tac 1152
Ala Ser Leu Val Gly Ile Ala Phe Ser Trp Glu Lys Gly Gln Gly Tyr
370 375 380
tac gtg ccc acg ccg ctg ccg gac ggc acg ccg acc gag acg gtg ctc 1200
Tyr Val Pro Thr Pro Leu Pro Asp Gly Thr Pro Thr Glu Thr Val Leu
385 390 395 400
gag cga ctg gcg ccg atc ctc cga cgg gcg cag cgc aaa gtc ggt cag 1248
Glu Arg Leu Ala Pro Ile Leu Arg Arg Ala Gln Arg Lys Val Gly Gln
405 410 415
aac ctg aag tac gat ctg gtg gtg ctg gcg cgg cac ggc gtc caa gtc 1296
Asn Leu Lys Tyr Asp Leu Val Val Leu Ala Arg His Gly Val Gln Val
420 425 430
ccg ccc ccg tac ttc gac acg atg gtg gcg cac tac ctg att gcg ccc 1344
Pro Pro Pro Tyr Phe Asp Thr Met Val Ala His Tyr Leu Ile Ala Pro
435 440 445
gag gaa ccg cat aac ctg gac gtg ctg gcc cgc cag tac ctt cgc tac 1392
Glu Glu Pro His Asn Leu Asp Val Leu Ala Arg Gln Tyr Leu Arg Tyr
450 455 460
cag atg gtt tcc atc acg gaa ctg atc ggc tcg ggt cgc gac cag aag 1440
Gln Met Val Ser Ile Thr Glu Leu Ile Gly Ser Gly Arg Asp Gln Lys
465 470 475 480
tcc atg cgc gac gtg tcg atc gac gag gtg ggg ccc tat gcc tgt gaa 1488
Ser Met Arg Asp Val Ser Ile Asp Glu Val Gly Pro Tyr Ala Cys Glu
485 490 495
gac acg gac att gcg ctg caa ctg gcc gat gtg ctg gcc gcc gag ttg 1536
Asp Thr Asp Ile Ala Leu Gln Leu Ala Asp Val Leu Ala Ala Glu Leu
500 505 510
gac cga cac gga ctc cgg cat atc gcc gag gag atg gag ttc ccg ctc 1584
Asp Arg His Gly Leu Arg His Ile Ala Glu Glu Met Glu Phe Pro Leu
515 520 525
atc gag gtg ctg gcc gat atg gag cgg acg ggc atc tgc atc gat cgc 1632
Ile Glu Val Leu Ala Asp Met Glu Arg Thr Gly Ile Cys Ile Asp Arg
530 535 540
gcg gtg ctt cgg gaa atc ggt aag caa ctc gaa gcg gag ctt cac gaa 1680
Ala Val Leu Arg Glu Ile Gly Lys Gln Leu Glu Ala Glu Leu His Glu
545 550 555 560
ctg gag gtg aag atc tat gag gtg gcc ggc gtc gaa ttc aac atc ggc 1728
Leu Glu Val Lys Ile Tyr Glu Val Ala Gly Val Glu Phe Asn Ile Gly
565 570 575
tcg ccg cag caa ctg gcg gac gtc ttg ttc aag aag ctc ggg ttg aag 1776
Ser Pro Gln Gln Leu Ala Asp Val Leu Phe Lys Lys Leu Gly Leu Lys
580 585 590
ccg cgg gcg cgc acc agc acc ggc cgg cct tcc acc aaa gag agc gtg 1824
Pro Arg Ala Arg Thr Ser Thr Gly Arg Pro Ser Thr Lys Glu Ser Val
595 600 605
ctg cag gag ctg gcc acg cag cac ccg ctc ccc ggc ctg atc ctg gac 1872
Leu Gln Glu Leu Ala Thr Gln His Pro Leu Pro Gly Leu Ile Leu Asp
610 615 620
tgg cga cac ctg gcc aag ctc aaa agc acc tac gtg gac ggc ctc gag 1920
Trp Arg His Leu Ala Lys Leu Lys Ser Thr Tyr Val Asp Gly Leu Glu
625 630 635 640
ccg ctc atc cat ccg gag acc ggc cgc atc cac acc acg ttc aac cag 1968
Pro Leu Ile His Pro Glu Thr Gly Arg Ile His Thr Thr Phe Asn Gln
645 650 655
acg gtg acg gct acc ggg cgg ctt tcc tcg agc aac ccg aac ctg cag 2016
Thr Val Thr Ala Thr Gly Arg Leu Ser Ser Ser Asn Pro Asn Leu Gln
660 665 670
aac atc ccg gtt cgc acc gag atg ggg cgg gag atc cgc agg gcg ttt 2064
Asn Ile Pro Val Arg Thr Glu Met Gly Arg Glu Ile Arg Arg Ala Phe
675 680 685
gtg ccg cgg ccg ggc tgg aag ctg ctc tcg gcc gac tac gtc cag atc 2112
Val Pro Arg Pro Gly Trp Lys Leu Leu Ser Ala Asp Tyr Val Gln Ile
690 695 700
gaa ctt cgc att ctg gcc gcg ctg agc ggc gac gag gcg ctt cgc cgg 2160
Glu Leu Arg Ile Leu Ala Ala Leu Ser Gly Asp Glu Ala Leu Arg Arg
705 710 715 720
gcc ttt ctg gag gga cag gac atc cat acg gcc acg gca gcc cgc gtc 2208
Ala Phe Leu Glu Gly Gln Asp Ile His Thr Ala Thr Ala Ala Arg Val
725 730 735
ttc aag gtg ccg ccc gag cag gtg acg ccc gag cag cgc cgc cgc gcc 2256
Phe Lys Val Pro Pro Glu Gln Val Thr Pro Glu Gln Arg Arg Arg Ala
740 745 750
aag atg gtc aac tac ggc att ccc tac ggg att tcg gcc tgg ggg ctg 2304
Lys Met Val Asn Tyr Gly Ile Pro Tyr Gly Ile Ser Ala Trp Gly Leu
755 760 765
gcg cag cgg ctt cgc tgc tcc acg cgc gag gcg cag gag ctt atc gaa 2352
Ala Gln Arg Leu Arg Cys Ser Thr Arg Glu Ala Gln Glu Leu Ile Glu
770 775 780
gaa tat cag cgg gcc ttt ccg ggc gtg acg cgc tac ctg cac cgc gtc 2400
Glu Tyr Gln Arg Ala Phe Pro Gly Val Thr Arg Tyr Leu His Arg Val
785 790 795 800
gtc gaa gag gcc cgc cag aag ggc tac gtc gag acg ctg ctg ggc cgc 2448
Val Glu Glu Ala Arg Gln Lys Gly Tyr Val Glu Thr Leu Leu Gly Arg
805 810 815
cgc cgc tac gta ccg aac atc aac tcc cgc aac cgg gcc gag cgc tcg 2496
Arg Arg Tyr Val Pro Asn Ile Asn Ser Arg Asn Arg Ala Glu Arg Ser
820 825 830
atg gcc gaa cgc atc gcc gtg aac atg ccc atc cag ggc acg cag gcc 2544
Met Ala Glu Arg Ile Ala Val Asn Met Pro Ile Gln Gly Thr Gln Ala
835 840 845
gac atg atc aag ctg gcc atg gtg cac atc tac cac cga ctg aag cgg 2592
Asp Met Ile Lys Leu Ala Met Val His Ile Tyr His Arg Leu Lys Arg
850 855 860
gaa ggc tac cgg gcc aag atg ctg ctc cag gtg cac gac gag ctg gtc 2640
Glu Gly Tyr Arg Ala Lys Met Leu Leu Gln Val His Asp Glu Leu Val
865 870 875 880
ttc gag atg ccc ccc gaa gag gtg gag ccc gtg cgc caa ctg gtc gag 2688
Phe Glu Met Pro Pro Glu Glu Val Glu Pro Val Arg Gln Leu Val Glu
885 890 895
cag gag atg aag cag gcc ctg ccg ctg gaa ggt gtg ccc atc gag gtg 2736
Gln Glu Met Lys Gln Ala Leu Pro Leu Glu Gly Val Pro Ile Glu Val
900 905 910
gac atc ggc gtc ggc gac aac tgg ctg gat gcc cac tga 2775
Asp Ile Gly Val Gly Asp Asn Trp Leu Asp Ala His
915 920
2
924
PRT
Rhodothermus obamensis
2
Met Gln Arg Leu Tyr Leu Ile Asp Ala Met Ala Leu Ala Tyr Arg Ala
1 5 10 15
Gln Tyr Val Phe Ile Ser Arg Pro Leu Val Asn Ser Lys Gly Gln Asn
20 25 30
Thr Ser Ala Ala Tyr Gly Phe Thr Thr Ser Leu Leu Lys Leu Ile Glu
35 40 45
Glu His Gly Met Asp Tyr Met Ala Val Val Phe Asp Ala Gly Gly Glu
50 55 60
Glu Gly Thr Phe Arg Glu Ala Ile Tyr Glu Glu Tyr Lys Ala His Arg
65 70 75 80
Glu Pro Pro Pro Glu Asp Leu Leu Ala Asn Leu Pro Trp Ile Lys Glu
85 90 95
Ile Val Arg Ala Leu Asp Ile Pro Val Ile Glu Glu Pro Gly Val Glu
100 105 110
Ala Asp Asp Val Ile Gly Thr Leu Ala Arg Arg Ala Glu Ala His Gly
115 120 125
Ile Asp Val Val Ile Val Ser Pro Asp Lys Asp Phe Leu Gln Leu Leu
130 135 140
Ser Pro His Val Ser Ile Tyr Lys Pro Ala Arg Arg Gly Glu Thr Phe
145 150 155 160
Asp Leu Ile Thr Ile Glu Thr Phe Arg Glu Thr Tyr Gly Leu Glu Pro
165 170 175
His Gln Phe Ile Asp Val Leu Ala Leu Met Gly Asp Pro Ser Asp Asn
180 185 190
Val Pro Gly Val Pro Gly Ile Gly Glu Lys Thr Ala Val Gln Leu Ile
195 200 205
Gln Gln Tyr Gly Ser Val Glu Asn Leu Leu Ala His Ala Glu Glu Val
210 215 220
Lys Gly Lys Arg Ala Arg Glu Gly Leu Leu Asn His Arg Glu Glu Ala
225 230 235 240
Leu Leu Ser Lys Arg Leu Val Thr Ile Arg Thr Asp Val Pro Leu Arg
245 250 255
Ile Arg Trp Glu Ala Phe His Arg Ala Arg Pro Asp Leu Pro Arg Leu
260 265 270
Leu Gln Ile Phe Gln Glu Leu Glu Phe Asp Ser Leu Val Arg Arg Ile
275 280 285
Arg Glu Gly Gly Leu Ala Gly Ile Val Asn Gly Glu Ala Ala Leu Asp
290 295 300
Glu Ala Leu Glu Ala Glu Thr Glu Pro Glu Phe Asp Phe Gly Pro Tyr
305 310 315 320
Glu Pro Leu Gln Val Tyr Asp Pro Glu Lys Ala Asp Tyr Arg Ile Val
325 330 335
Arg Asn Arg Gln Gln Leu Asp Glu Leu Val Ala His Leu Asp Gly Phe
340 345 350
Glu Arg Leu Ala Ile Asp Thr Glu Thr Thr Ser Thr Glu Ala Met Trp
355 360 365
Ala Ser Leu Val Gly Ile Ala Phe Ser Trp Glu Lys Gly Gln Gly Tyr
370 375 380
Tyr Val Pro Thr Pro Leu Pro Asp Gly Thr Pro Thr Glu Thr Val Leu
385 390 395 400
Glu Arg Leu Ala Pro Ile Leu Arg Arg Ala Gln Arg Lys Val Gly Gln
405 410 415
Asn Leu Lys Tyr Asp Leu Val Val Leu Ala Arg His Gly Val Gln Val
420 425 430
Pro Pro Pro Tyr Phe Asp Thr Met Val Ala His Tyr Leu Ile Ala Pro
435 440 445
Glu Glu Pro His Asn Leu Asp Val Leu Ala Arg Gln Tyr Leu Arg Tyr
450 455 460
Gln Met Val Ser Ile Thr Glu Leu Ile Gly Ser Gly Arg Asp Gln Lys
465 470 475 480
Ser Met Arg Asp Val Ser Ile Asp Glu Val Gly Pro Tyr Ala Cys Glu
485 490 495
Asp Thr Asp Ile Ala Leu Gln Leu Ala Asp Val Leu Ala Ala Glu Leu
500 505 510
Asp Arg His Gly Leu Arg His Ile Ala Glu Glu Met Glu Phe Pro Leu
515 520 525
Ile Glu Val Leu Ala Asp Met Glu Arg Thr Gly Ile Cys Ile Asp Arg
530 535 540
Ala Val Leu Arg Glu Ile Gly Lys Gln Leu Glu Ala Glu Leu His Glu
545 550 555 560
Leu Glu Val Lys Ile Tyr Glu Val Ala Gly Val Glu Phe Asn Ile Gly
565 570 575
Ser Pro Gln Gln Leu Ala Asp Val Leu Phe Lys Lys Leu Gly Leu Lys
580 585 590
Pro Arg Ala Arg Thr Ser Thr Gly Arg Pro Ser Thr Lys Glu Ser Val
595 600 605
Leu Gln Glu Leu Ala Thr Gln His Pro Leu Pro Gly Leu Ile Leu Asp
610 615 620
Trp Arg His Leu Ala Lys Leu Lys Ser Thr Tyr Val Asp Gly Leu Glu
625 630 635 640
Pro Leu Ile His Pro Glu Thr Gly Arg Ile His Thr Thr Phe Asn Gln
645 650 655
Thr Val Thr Ala Thr Gly Arg Leu Ser Ser Ser Asn Pro Asn Leu Gln
660 665 670
Asn Ile Pro Val Arg Thr Glu Met Gly Arg Glu Ile Arg Arg Ala Phe
675 680 685
Val Pro Arg Pro Gly Trp Lys Leu Leu Ser Ala Asp Tyr Val Gln Ile
690 695 700
Glu Leu Arg Ile Leu Ala Ala Leu Ser Gly Asp Glu Ala Leu Arg Arg
705 710 715 720
Ala Phe Leu Glu Gly Gln Asp Ile His Thr Ala Thr Ala Ala Arg Val
725 730 735
Phe Lys Val Pro Pro Glu Gln Val Thr Pro Glu Gln Arg Arg Arg Ala
740 745 750
Lys Met Val Asn Tyr Gly Ile Pro Tyr Gly Ile Ser Ala Trp Gly Leu
755 760 765
Ala Gln Arg Leu Arg Cys Ser Thr Arg Glu Ala Gln Glu Leu Ile Glu
770 775 780
Glu Tyr Gln Arg Ala Phe Pro Gly Val Thr Arg Tyr Leu His Arg Val
785 790 795 800
Val Glu Glu Ala Arg Gln Lys Gly Tyr Val Glu Thr Leu Leu Gly Arg
805 810 815
Arg Arg Tyr Val Pro Asn Ile Asn Ser Arg Asn Arg Ala Glu Arg Ser
820 825 830
Met Ala Glu Arg Ile Ala Val Asn Met Pro Ile Gln Gly Thr Gln Ala
835 840 845
Asp Met Ile Lys Leu Ala Met Val His Ile Tyr His Arg Leu Lys Arg
850 855 860
Glu Gly Tyr Arg Ala Lys Met Leu Leu Gln Val His Asp Glu Leu Val
865 870 875 880
Phe Glu Met Pro Pro Glu Glu Val Glu Pro Val Arg Gln Leu Val Glu
885 890 895
Gln Glu Met Lys Gln Ala Leu Pro Leu Glu Gly Val Pro Ile Glu Val
900 905 910
Asp Ile Gly Val Gly Asp Asn Trp Leu Asp Ala His
915 920
3
1887
DNA
Rhodothermus obamensis
CDS
(1)..(1884)
3
atg aac ggc gaa gcc gcc ttg gat gag gcg ctt gaa gcg gag acc gag 48
Met Asn Gly Glu Ala Ala Leu Asp Glu Ala Leu Glu Ala Glu Thr Glu
1 5 10 15
ccg gag ttc gat ttc ggg cca tac gag ccg ctg cag gtg tac gat ccg 96
Pro Glu Phe Asp Phe Gly Pro Tyr Glu Pro Leu Gln Val Tyr Asp Pro
20 25 30
gaa aag gcg gac tac cgg atc gtc cgc aac cgc cag cag ctc gac gaa 144
Glu Lys Ala Asp Tyr Arg Ile Val Arg Asn Arg Gln Gln Leu Asp Glu
35 40 45
ctc gtg gcg cat ctg gac gga ttc gaa cgg ctg gcc atc gac acg gag 192
Leu Val Ala His Leu Asp Gly Phe Glu Arg Leu Ala Ile Asp Thr Glu
50 55 60
acg act tcg acc gag gcc atg tgg gcc tcg ctg gtg ggc att gcc ttt 240
Thr Thr Ser Thr Glu Ala Met Trp Ala Ser Leu Val Gly Ile Ala Phe
65 70 75 80
tcc tgg gag aaa ggc cag ggc tac tac gtg ccc acg ccg ctg ccg gac 288
Ser Trp Glu Lys Gly Gln Gly Tyr Tyr Val Pro Thr Pro Leu Pro Asp
85 90 95
ggc acg ccg acc gag acg gtg ctc gag cga ctg gcg ccg atc ctc cga 336
Gly Thr Pro Thr Glu Thr Val Leu Glu Arg Leu Ala Pro Ile Leu Arg
100 105 110
cgg gcg cag cgc aaa gtc ggt cag aac ctg aag tac gat ctg gtg gtg 384
Arg Ala Gln Arg Lys Val Gly Gln Asn Leu Lys Tyr Asp Leu Val Val
115 120 125
ctg gcg cgg cac ggc gtc caa gtc ccg ccc ccg tac ttc gac acg atg 432
Leu Ala Arg His Gly Val Gln Val Pro Pro Pro Tyr Phe Asp Thr Met
130 135 140
gtg gcg cac tac ctg att gcg ccc gag gaa ccg cat aac ctg gac gtg 480
Val Ala His Tyr Leu Ile Ala Pro Glu Glu Pro His Asn Leu Asp Val
145 150 155 160
ctg gcc cgc cag tac ctt cgc tac cag atg gtt tcc atc acg gaa ctg 528
Leu Ala Arg Gln Tyr Leu Arg Tyr Gln Met Val Ser Ile Thr Glu Leu
165 170 175
atc ggc tcg ggt cgc gac cag aag tcc atg cgc gac gtg tcg atc gac 576
Ile Gly Ser Gly Arg Asp Gln Lys Ser Met Arg Asp Val Ser Ile Asp
180 185 190
gag gtg ggg ccc tat gcc tgt gaa gac acg gac att gcg ctg caa ctg 624
Glu Val Gly Pro Tyr Ala Cys Glu Asp Thr Asp Ile Ala Leu Gln Leu
195 200 205
gcc gat gtg ctg gcc gcc gag ttg gac cga cac gga ctc cgg cat atc 672
Ala Asp Val Leu Ala Ala Glu Leu Asp Arg His Gly Leu Arg His Ile
210 215 220
gcc gag gag atg gag ttc ccg ctc atc gag gtg ctg gcc gat atg gag 720
Ala Glu Glu Met Glu Phe Pro Leu Ile Glu Val Leu Ala Asp Met Glu
225 230 235 240
cgg acg ggc atc tgc atc gat cgc gcg gtg ctt cgg gaa atc ggt aag 768
Arg Thr Gly Ile Cys Ile Asp Arg Ala Val Leu Arg Glu Ile Gly Lys
245 250 255
caa ctc gaa gcg gag ctt cac gaa ctg gag gtg aag atc tat gag gtg 816
Gln Leu Glu Ala Glu Leu His Glu Leu Glu Val Lys Ile Tyr Glu Val
260 265 270
gcc ggc gtc gaa ttc aac atc ggc tcg ccg cag caa ctg gcg gac gtc 864
Ala Gly Val Glu Phe Asn Ile Gly Ser Pro Gln Gln Leu Ala Asp Val
275 280 285
ttg ttc aag aag ctc ggg ttg aag ccg cgg gcg cgc acc agc acc ggc 912
Leu Phe Lys Lys Leu Gly Leu Lys Pro Arg Ala Arg Thr Ser Thr Gly
290 295 300
cgg cct tcc acc aaa gag agc gtg ctg cag gag ctg gcc acg cag cac 960
Arg Pro Ser Thr Lys Glu Ser Val Leu Gln Glu Leu Ala Thr Gln His
305 310 315 320
ccg ctc ccc ggc ctg atc ctg gac tgg cga cac ctg gcc aag ctc aaa 1008
Pro Leu Pro Gly Leu Ile Leu Asp Trp Arg His Leu Ala Lys Leu Lys
325 330 335
agc acc tac gtg gac ggc ctc gag ccg ctc atc cat ccg gag acc ggc 1056
Ser Thr Tyr Val Asp Gly Leu Glu Pro Leu Ile His Pro Glu Thr Gly
340 345 350
cgc atc cac acc acg ttc aac cag acg gtg acg gct acc ggg cgg ctt 1104
Arg Ile His Thr Thr Phe Asn Gln Thr Val Thr Ala Thr Gly Arg Leu
355 360 365
tcc tcg agc aac ccg aac ctg cag aac atc ccg gtt cgc acc gag atg 1152
Ser Ser Ser Asn Pro Asn Leu Gln Asn Ile Pro Val Arg Thr Glu Met
370 375 380
ggg cgg gag atc cgc agg gcg ttt gtg ccg cgg ccg ggc tgg aag ctg 1200
Gly Arg Glu Ile Arg Arg Ala Phe Val Pro Arg Pro Gly Trp Lys Leu
385 390 395 400
ctc tcg gcc gac tac gtc cag atc gaa ctt cgc att ctg gcc gcg ctg 1248
Leu Ser Ala Asp Tyr Val Gln Ile Glu Leu Arg Ile Leu Ala Ala Leu
405 410 415
agc ggc gac gag gcg ctt cgc cgg gcc ttt ctg gag gga cag gac atc 1296
Ser Gly Asp Glu Ala Leu Arg Arg Ala Phe Leu Glu Gly Gln Asp Ile
420 425 430
cat acg gcc acg gca gcc cgc gtc ttc aag gtg ccg ccc gag cag gtg 1344
His Thr Ala Thr Ala Ala Arg Val Phe Lys Val Pro Pro Glu Gln Val
435 440 445
acg ccc gag cag cgc cgc cgc gcc aag atg gtc aac tac ggc att ccc 1392
Thr Pro Glu Gln Arg Arg Arg Ala Lys Met Val Asn Tyr Gly Ile Pro
450 455 460
tac ggg att tcg gcc tgg ggg ctg gcg cag cgg ctt cgc tgc tcc acg 1440
Tyr Gly Ile Ser Ala Trp Gly Leu Ala Gln Arg Leu Arg Cys Ser Thr
465 470 475 480
cgc gag gcg cag gag ctt atc gaa gaa tat cag cgg gcc ttt ccg ggc 1488
Arg Glu Ala Gln Glu Leu Ile Glu Glu Tyr Gln Arg Ala Phe Pro Gly
485 490 495
gtg acg cgc tac ctg cac cgc gtc gtc gaa gag gcc cgc cag aag ggc 1536
Val Thr Arg Tyr Leu His Arg Val Val Glu Glu Ala Arg Gln Lys Gly
500 505 510
tac gtc gag acg ctg ctg ggc cgc cgc cgc tac gta ccg aac atc aac 1584
Tyr Val Glu Thr Leu Leu Gly Arg Arg Arg Tyr Val Pro Asn Ile Asn
515 520 525
tcc cgc aac cgg gcc gag cgc tcg atg gcc gaa cgc atc gcc gtg aac 1632
Ser Arg Asn Arg Ala Glu Arg Ser Met Ala Glu Arg Ile Ala Val Asn
530 535 540
atg ccc atc cag ggc acg cag gcc gac atg atc aag ctg gcc atg gtg 1680
Met Pro Ile Gln Gly Thr Gln Ala Asp Met Ile Lys Leu Ala Met Val
545 550 555 560
cac atc tac cac cga ctg aag cgg gaa ggc tac cgg gcc aag atg ctg 1728
His Ile Tyr His Arg Leu Lys Arg Glu Gly Tyr Arg Ala Lys Met Leu
565 570 575
ctc cag gtg cac gac gag ctg gtc ttc gag atg ccc ccc gaa gag gtg 1776
Leu Gln Val His Asp Glu Leu Val Phe Glu Met Pro Pro Glu Glu Val
580 585 590
gag ccc gtg cgc caa ctg gtc gag cag gag atg aag cag gcc ctg ccg 1824
Glu Pro Val Arg Gln Leu Val Glu Gln Glu Met Lys Gln Ala Leu Pro
595 600 605
ctg gaa ggt gtg ccc atc gag gtg gac atc ggc gtc ggc gac aac tgg 1872
Leu Glu Gly Val Pro Ile Glu Val Asp Ile Gly Val Gly Asp Asn Trp
610 615 620
ctg gat gcc cac tga 1887
Leu Asp Ala His
625
4
628
PRT
Rhodothermus obamensis
4
Met Asn Gly Glu Ala Ala Leu Asp Glu Ala Leu Glu Ala Glu Thr Glu
1 5 10 15
Pro Glu Phe Asp Phe Gly Pro Tyr Glu Pro Leu Gln Val Tyr Asp Pro
20 25 30
Glu Lys Ala Asp Tyr Arg Ile Val Arg Asn Arg Gln Gln Leu Asp Glu
35 40 45
Leu Val Ala His Leu Asp Gly Phe Glu Arg Leu Ala Ile Asp Thr Glu
50 55 60
Thr Thr Ser Thr Glu Ala Met Trp Ala Ser Leu Val Gly Ile Ala Phe
65 70 75 80
Ser Trp Glu Lys Gly Gln Gly Tyr Tyr Val Pro Thr Pro Leu Pro Asp
85 90 95
Gly Thr Pro Thr Glu Thr Val Leu Glu Arg Leu Ala Pro Ile Leu Arg
100 105 110
Arg Ala Gln Arg Lys Val Gly Gln Asn Leu Lys Tyr Asp Leu Val Val
115 120 125
Leu Ala Arg His Gly Val Gln Val Pro Pro Pro Tyr Phe Asp Thr Met
130 135 140
Val Ala His Tyr Leu Ile Ala Pro Glu Glu Pro His Asn Leu Asp Val
145 150 155 160
Leu Ala Arg Gln Tyr Leu Arg Tyr Gln Met Val Ser Ile Thr Glu Leu
165 170 175
Ile Gly Ser Gly Arg Asp Gln Lys Ser Met Arg Asp Val Ser Ile Asp
180 185 190
Glu Val Gly Pro Tyr Ala Cys Glu Asp Thr Asp Ile Ala Leu Gln Leu
195 200 205
Ala Asp Val Leu Ala Ala Glu Leu Asp Arg His Gly Leu Arg His Ile
210 215 220
Ala Glu Glu Met Glu Phe Pro Leu Ile Glu Val Leu Ala Asp Met Glu
225 230 235 240
Arg Thr Gly Ile Cys Ile Asp Arg Ala Val Leu Arg Glu Ile Gly Lys
245 250 255
Gln Leu Glu Ala Glu Leu His Glu Leu Glu Val Lys Ile Tyr Glu Val
260 265 270
Ala Gly Val Glu Phe Asn Ile Gly Ser Pro Gln Gln Leu Ala Asp Val
275 280 285
Leu Phe Lys Lys Leu Gly Leu Lys Pro Arg Ala Arg Thr Ser Thr Gly
290 295 300
Arg Pro Ser Thr Lys Glu Ser Val Leu Gln Glu Leu Ala Thr Gln His
305 310 315 320
Pro Leu Pro Gly Leu Ile Leu Asp Trp Arg His Leu Ala Lys Leu Lys
325 330 335
Ser Thr Tyr Val Asp Gly Leu Glu Pro Leu Ile His Pro Glu Thr Gly
340 345 350
Arg Ile His Thr Thr Phe Asn Gln Thr Val Thr Ala Thr Gly Arg Leu
355 360 365
Ser Ser Ser Asn Pro Asn Leu Gln Asn Ile Pro Val Arg Thr Glu Met
370 375 380
Gly Arg Glu Ile Arg Arg Ala Phe Val Pro Arg Pro Gly Trp Lys Leu
385 390 395 400
Leu Ser Ala Asp Tyr Val Gln Ile Glu Leu Arg Ile Leu Ala Ala Leu
405 410 415
Ser Gly Asp Glu Ala Leu Arg Arg Ala Phe Leu Glu Gly Gln Asp Ile
420 425 430
His Thr Ala Thr Ala Ala Arg Val Phe Lys Val Pro Pro Glu Gln Val
435 440 445
Thr Pro Glu Gln Arg Arg Arg Ala Lys Met Val Asn Tyr Gly Ile Pro
450 455 460
Tyr Gly Ile Ser Ala Trp Gly Leu Ala Gln Arg Leu Arg Cys Ser Thr
465 470 475 480
Arg Glu Ala Gln Glu Leu Ile Glu Glu Tyr Gln Arg Ala Phe Pro Gly
485 490 495
Val Thr Arg Tyr Leu His Arg Val Val Glu Glu Ala Arg Gln Lys Gly
500 505 510
Tyr Val Glu Thr Leu Leu Gly Arg Arg Arg Tyr Val Pro Asn Ile Asn
515 520 525
Ser Arg Asn Arg Ala Glu Arg Ser Met Ala Glu Arg Ile Ala Val Asn
530 535 540
Met Pro Ile Gln Gly Thr Gln Ala Asp Met Ile Lys Leu Ala Met Val
545 550 555 560
His Ile Tyr His Arg Leu Lys Arg Glu Gly Tyr Arg Ala Lys Met Leu
565 570 575
Leu Gln Val His Asp Glu Leu Val Phe Glu Met Pro Pro Glu Glu Val
580 585 590
Glu Pro Val Arg Gln Leu Val Glu Gln Glu Met Lys Gln Ala Leu Pro
595 600 605
Leu Glu Gly Val Pro Ile Glu Val Asp Ile Gly Val Gly Asp Asn Trp
610 615 620
Leu Asp Ala His
625
5
26
DNA
synthetic
5
tccgayccca acctscagaa catccc 26
6
23
DNA
Synthetic
6
aggassagct cgtcgtgsac ctg 23
7
21
DNA
synthetic
7
cgcagggcgt ttgtgccgcg g 21
8
21
DNA
synthetic
8
gtctcccgcc ccatctcggt g 21
9
21
DNA
synthetic
9
gccggccgct tgtcaactcg a 21
10
21
DNA
synthetic
10
tgatgaacac gtattgcgcc c 21
11
24
DNA
Synthetic
11
gaagcgggaa ggctaccggg ccaa 24
12
24
DNA
Synthetic
12
agtcggtggt agatgtgcac catg 24
13
39
DNA
Synthetic
13
ctggccggcc atatgaacgg cgaagccgcc ttggatgag 39
14
36
DNA
Synthetic
14
gttggatccg cttcagtggg catccagcca gttgtc 36
15
15
PRT
Escherichia coli
15
Ala Ala Lys Asp Val Lys Phe Gly Asn Asp Ala Arg Val Lys Met
1 5 10 15 | The present invention provides a novel thermostable DNA polymerase I obtainable from Rhodothermus obamensis , which possesses 3′-5′ exonuclease activity and has a half-life of about 35 minutes at 94° C. This polymerase also contains a tyrosine residue in the ribosome binding site which improves incorporation of dideoxyribonucleic acids. Also provided are isolated DNA and vectors encoding this polymerase, as well as its large fragment, and methods for producing recombinant enzyme using the same. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This patent application is related to co-pending, commonly-owned U.S. patent application Ser. No. (undetermined) entitled “Methods And Systems For Direct Manufacturing Temperature Control”, filed under Attorney Docket No. 07-0192 (24691-124) concurrently herewith on Apr. 20, 2007, which application is hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The invention relates to methods and systems for adjusting heat distribution, and more specifically, to methods and systems for controlling and adjusting heat distribution over a part bed.
BACKGROUND OF THE INVENTION
[0003] People often desire to create prototypes or production models of products, including products with complex geometries. Additive manufacturing techniques facilitate the creation of products using a bottom-up product building approach by adding material in thin layers to form a product. This process allows product creation without large capital investments, such as those associated with molds or specialized machinery, while reducing the overall waste generated in product creation. Additive manufacturing techniques also allow creation of a product with complex geometry because the additive process creates a thin cross-sectional slice of the product during each iteration, thus building complex geometries as simple two-dimensional layers created upon one-another.
[0004] When a product is formed using an additive manufacturing process, the raw material (e.g., powder) is heated to an optimal temperature for product formation. The optimal temperature is slightly lower than the liquid state temperature of the material, thus allowing a small concentration of thermal energy (heat) from a laser to transform the solid material to a liquid, where the material then bonds and quickly cools (after removal of the laser) as a product layer. Often, the material in the part bed has inconsistent temperature when the temperature is measured across the part bed. This variance in temperature may reduce the integrity and consistency of the product formation process in additive manufacturing. In addition, the raw materials that may be used in additive manufacturing have various formation temperatures (i.e., melting points). Some raw materials have melting points that are too high for current additive manufacturing systems to utilize, particularly when large variances in temperature exist across the part bed.
SUMMARY
[0005] Embodiments of methods and systems for controlling and adjusting heat distribution over a part bed are disclosed. In one embodiment, a method for providing a target heat distribution over a part bed includes determining a temperature distribution within a part bed, generating a zone heat distribution for a plurality of heat zones from the temperature distribution, analyzing the zone heat distribution to create an adjustment command to adjust a heater for providing a target (uniform or non-uniform) temperature distribution within the part bed, and adjusting the heater based on the adjustment command.
[0006] In another embodiment, a system for providing a target heat distribution over a part bed includes a thermal imaging device to generate temperature distribution data from material in a part bed. A processor receives the temperature distribution data, converts the temperature distribution data into a zone temperature grid, creates a heater control command based on a difference between a target temperature and the zone temperature grid, and transmits the heater control command to at least one heater element of a plurality of heater elements.
[0007] In yet another embodiment, one or more computer readable media comprise computer-executable instructions that, when executed by a computer, perform acts which include measuring a temperature distribution of a part bed, generating temperature zones from the temperature distribution, and creating a heater adjustment command from the temperature zones to adjust at least one of a plurality of heaters to provide a target (uniform or non-uniform) temperature distribution over the part bed.
[0008] The features, functions, and advantages can be achieved independently in various embodiments of the present inventions or may be combined in yet other embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Embodiments of systems and methods in accordance with the present disclosure are described in detail below with reference to the following drawings.
[0010] FIG. 1 is a schematic of an environment for controlling and adjusting heat distribution over a part bed in accordance with an embodiment of the invention;
[0011] FIGS. 2 a , 2 b , and 2 c are charts illustrating different temperature distribution ranges for a part bed in accordance with an embodiment of the invention;
[0012] FIG. 3 a and 3 b are top plan views from an IR camera perspective of temperature distributions of a part bed, including zones of the part bed, in accordance with another embodiment of the invention;
[0013] FIG. 4 is a schematic of an exemplary zone grid configuration of a part bed in accordance with an embodiment of the invention;
[0014] FIG. 5 is a flow chart of a method for controlling and adjusting the heat distribution over a part bed in accordance with another embodiment of the invention; and
[0015] FIG. 6 is a flow chart of a closed loop process for controlling and adjusting the heat distribution over a part bed in accordance with another embodiment of the invention.
DETAILED DESCRIPTION
[0016] Methods and systems for controlling and adjusting a heat distribution over a part bed are described herein. Many specific details of certain embodiments of the invention are set forth in the following description and in FIGS. 1 through 6 to provide a thorough understanding of such embodiments. One skilled in the art, however, will understand that the present invention may have additional embodiments, or that the present invention may be practiced without several of the details described in the following description.
[0017] FIG. 1 illustrates an overall environment 100 for controlling and adjusting a heat distribution over a part bed in accordance with an embodiment of the invention. The environment 100 includes a part bed 102 and a heater tray 104 for heating the part bed 102 . The part bed 102 (also referred to as a powder bed) is used to create products in an additive manufacturing process such as laser sintering (LS) or selective laser sintering (SLS), a registered trademark of 3D Systems, Inc. of Rock Hill, S.C., USA.
[0018] Generally, in an LS system, a thin layer of powder is spread across the part bed 102 . The layer of powder is heated by the heater tray 104 to an optimal product formation temperature. A laser beam from a laser 106 is directed at the powder on the part bed 102 to form a layer of the desired product from the powder. As noted above, with the powder heated by the heater tray 104 to a temperature slightly lower than the liquid state temperature of the powder, thermal energy (heat) from the laser 106 transforms the solid material to a liquid. After the laser is removed, the material cools and re-solidifies. The laser 106 bonds the powder elements to form a solid, thin product layer, one layer at a time. After the thin product layer (or slice) has been formed, another thin layer of powder is spread across the part bed 102 to create another thin product layer of the product on top of the previous thin product layer. This process is repeated until the desired product is fully formed, often after many iterations of the above-described process. Embodiments of systems and methods in accordance with the teachings of the present disclosure may advantageously be used to provide a desired temperature distribution over the powder in the part bed 102 (including uniform or non-uniform temperature distributions), thereby improving the consistency of the manufacturing process and the quality of the resulting components.
[0019] The heater tray 104 may include any number of heaters 108 . The heaters 108 emit heat towards the powder in the part bed 102 , thus heating the powder to the desired temperature for product formation. In an exemplary embodiment, the heater tray 104 includes eight heaters 108 , however, any number of heaters may be used. The eight heaters 108 may be configured on the heater tray 104 to include one heater for each corner and one heater for each side of the heater tray. The heaters 108 may be repositioned or adjusted on the heater tray 104 to provide an even heat distribution to the powder on the part bed 102 . For example, in some embodiments, a heater 108 may translate along a plane in a side to side or fore to aft direction, or it may rotate about a mounting point near the heater tray 104 and therefore direct heat to the optimal portion of the part bed 102 . The heaters 108 may be in connection with variable resisters 112 and a power source 114 to control the energy output of the heaters 108 . Further, each heater 108 may have an adjustable current or voltage applied to the heat radiator to variably control the local energy density applied to the powder in the part bed 102 .
[0020] In some embodiments, the heaters 108 are quartz rod elements, which are stable at temperatures in excess of 400° Celsius. In an exemplary embodiment, the heaters 108 may produce and maintain a consistent and stable temperature between 20° Celsius and 400° Celsius. Of course, in alternate embodiments, any suitable heating elements operable over any desired operating ranges may be used.
[0021] The environment 100 further includes an infrared (IR) camera 116 to capture images that indicate the temperature distribution across the powder in the part bed 102 . The IR camera 116 may be any thermal imaging device capable of measuring the temperature distribution of the powder on the part bed 102 and outputting temperature distribution data. The IR camera 116 may, for example, infer temperature from the measured infrared intensity by assuming the powder emits infrared radiation according to an established model of radiant intensity (e.g. black body emitter, etc.). In some embodiments, the IR camera 116 may be suspended above the part bed 102 and directed approximately perpendicular to the powder surface, thus being pointed directly at the powder bed to capture temperature (or heat) distribution data.
[0022] The IR camera 116 may have an energy wavelength detection band (or range) that is outside the energy wavelength band of the laser 106 . This may allow the IR camera 116 to monitor the temperature of the powder while the laser 106 is scanning the product, thus the data captured by the IR camera 116 may not be instantaneously affected by the laser's energy output.
[0023] The data captured by the IR camera 116 may be used to generate a zone heat distribution 118 . The zone heat distribution 118 is a representation of the temperatures for each zone corresponding to the part bed. Each heater 108 influences the temperature of at least one zone. For example, the second heater 108 ( 2 ) may be adjusted to increase or decrease the temperature of zone 2 in the zone heat distribution 118 . The temperature of the second heater 108 ( 2 ) may also influence the temperature of the adjacent zones 5 , 6 , and 9 . Although the zone heat distribution 118 depicts nine zones, the temperature gradient of the powder on the part bed 102 may be divided into any number of temperature zones.
[0024] In an embodiment, the IR camera 116 outputs temperature distribution data in the form of pixilated data. The zone heat distribution 118 may be created by the IR camera 116 , such as by algorithms that output the captured data by zones. The zones may include one or more pixels compiled to create a temperature for each zone. In another embodiment, the IR camera 116 data may be processed by software to create the zone heat distribution 118 . A central processing unit (CPU) 120 , such as a computer, may be utilized to analyze the distribution 118 to determine the temperatures associated with each zone. In some embodiments, the temperatures may be calculated using an average, median, root mean square, or other zone temperature calculation to generate a single temperature for each zone in the zone heat distribution 118 .
[0025] As further shown in FIG. 1 , the CPU 120 may analyze the data from the zone heat distribution 118 and generate an individual zone control output 122 . The zone control output 122 may be utilized to reposition the heaters 108 (e.g., translate side to side, fore to aft, rotate), adjust the power source, or adjust the resistance to produce a desired temperature distribution over the powder in the powder bed, including a uniform or non-uniform distribution. It will be appreciated that for many applications, a uniform, approximately constant temperature across the powder in the part bed is desired. For example, the CPU 120 may determine that zone 2 is 4° C. warmer than a target temperature (e.g., 163° C.) in the zone heat distribution 118 . The CPU 120 may then reduce the temperature in zone 2 by performing one or more of the following: increasing the resistance from the variable resistors 112 , reducing the power source 114 for the heater (or heaters) 108 associated with zone 2 , and repositioning one or more heaters 108 , including the second heater 108 ( 2 ) that may be located directly proximate to zone 2 . After one or more of the previously described adjustments occur, the temperature of zone 2 should be equivalent to a target temperature according to the desired temperature distribution.
[0026] The CPU 120 may include one or more processors 124 that are coupled to instances of a user interface (UT) 126 . The UT 126 represents any devices and related drivers that enable the CPU 120 to receive input from a user, system, or device (e.g., signal from the IR camera 116 ), and to provide output to the user, system, or process. Thus, to receive inputs, the UT 126 may include keyboards or keypads, mouse devices, touch screens, microphones, speech recognition packages, imaging systems, or the like in addition to networking connection from other devices such as the IR camera 116 . Similarly, to provide outputs, the UT 126 may include speakers, display screens, printing mechanisms, or the like in addition to networking connections to other devices such as the variable resistors 112 , the power source 114 , and the heaters 108 .
[0027] The CPU 120 may include one or more instances of a computer-readable storage medium 128 that are addressable by the processor 124 . As such, the processor 124 may read data or executable instructions from, or store data to, the storage medium 128 . The storage medium 128 may contain a number of modules 130 (e.g., a module A and a module B) which may be implemented as one or more software modules that, when loaded into the processor 124 and executed, cause the CPU 120 to perform any of the functions described herein. In one embodiment, the module A may receive a signal from the IR camera 116 , process the signal, and create the zone heat distribution 118 . In a further embodiment, the module B may create and execute the zone control output 122 by manipulating the heaters 108 as described above. Additionally, the storage medium 128 may contain implementations of any of the various software modules described herein.
[0028] With continued reference to FIG. 1 , the environment 100 may further include other devices for measuring the temperature of the powder in the part bed 102 to create the zone heat distribution 118 . For example, thermocouples 132 may be positioned within, or adjacent to, the part bed 102 to measure the temperature of the powder. Other devices may be used in conjunction with the IR camera 116 , or they may be used as a substitute for the IR camera 116 , to measure the temperature of the powder in the part bed 102 .
[0029] The variable resistors 112 , the power sources 114 , and the heaters 108 may be arranged in different configurations. In some embodiments, each heater 108 may be configured with its own variable resistors 112 and power source 114 . In other embodiments, the heater 108 may share a common set of variable resistors 112 , a common power source 114 , or both. Additionally, the variable resistors 112 , the power sources 114 , and the heaters 108 may be configured in a series or parallel. Other configurations of these elements which facilitate the functionality described herein are also contemplated.
[0030] FIGS. 2 a , 2 b , and 2 c illustrate different temperature distribution ranges 202 , 204 , 206 , respectively, for a part bed in accordance with an embodiment of the invention. The temperature distribution ranges 202 , 204 , 206 are generated by plotting the temperature of the powder in the part bed to create a three-dimensional graphical representation of the temperature distribution across the powder. The part bed has an area enclosed by part formation borders 208 , 210 , 212 that circumscribes the area for temperature control. Products are created within the part formation borders 208 , 210 , 212 where the temperature may be maintained in accordance with a desired (or target) temperature distribution. The temperature of the zone outside of the border is not relevant to the process.
[0031] In some embodiments, the desired temperature distribution of the part bed is approximately constant across the zone heat distributions (or heat gradient), and thus a graphical representation depicts an approximately flat surface on a profile 214 , 216 , 218 . When the part bed has an inconsistent or uneven temperature distribution of the powder in the part bed, the graphical representation will appear inconsistent with features 220 , 222 including dips, valleys, ridges, elevations and other non-uniformities that represent inconsistencies of the temperature across the powder in the part bed. In comparison, the temperature distribution range 206 in FIG. 2 c is relatively flat and thus has no significantly distinct features on the surface 224 . This indicates an approximately constant temperature of the powder in the part bed. In contrast, the temperature distribution range 202 in FIG. 2 a has a curved profile 214 and distinct features 220 representing large inconsistencies in temperature across the powder in the part bed. For example, the temperature distribution range 202 may be a graph of the temperature distribution before control and adjustment. Further, the temperature distribution range 204 in FIG. 2 b has a relatively flat profile 216 , but still contains distinct features 222 representing large inconsistencies in temperature across the powder in the part bed. For example, the temperature distribution range 204 may be a graph of the temperature distribution after an initial or rough adjustment, or before equilibrium across the part bed has been reached. Therefore, the temperature distribution range 206 depicts a desired (or target) temperature distribution using the methods and systems for controlling and adjusting heat distribution over a part bed as disclosed herein.
[0032] FIGS. 3 a and 3 b are top plan views from an IR camera perspective of temperature distributions 302 , 304 , respectively, of a part bed including zones in accordance with another embodiment of the invention. The temperature distributions 302 , 304 depict variations in the temperature across the powder and is represented by color or gray-scale variances (i.e., consistent color or shading equates to an even temperature). The temperature distribution 304 in FIG. 3 b , utilizing the methods and systems for controlling and adjusting heat distribution over a part bed as disclosed herein, depicts a desired (or target) temperature distribution that is more consistent temperature across the part bed than the temperature distribution 302 in FIG. 3 a.
[0033] In FIG. 3 a , the part bed has a part formation border 306 circumscribing multiple heater zones 308 . In one embodiment, the nine heater zones 308 are utilized for controlling and adjusting heat distribution over a part bed, however, fewer or more zones may be utilized. The temperature distribution 302 illustrates the powder temperature before adjustment of the heaters, and includes a warmer temperature at a first point 310 (light color/shade) and a cooler temperature at a second point 312 (dark color/shade), thus illustrating a relatively inconsistent temperature distribution 302 . In FIG. 3 b , the part bed has a part formation border 314 circumscribing multiple heater zones 316 . The temperature distribution 304 illustrates the powder temperature after adjustment of the heaters, with a first point 318 that has a substantially similar (or approximately constant) temperature as a second point 320 . Therefore, unlike the temperature distribution 302 in FIG. 3 a , the temperature distribution 304 in FIG. 3 b illustrates a relatively consistent temperature distribution 304 .
[0034] FIG. 4 is a schematic of an exemplary zone grid 400 of a part bed in accordance with an embodiment of the invention. The zone grid 400 overlays a part bed 402 that further includes a product formation border 404 . As previously described, parts are formed within the product formation border 404 where the temperature is controlled to a desired (or target) temperature distribution. For example, in a particular embodiment, the zone grid 400 may be divided into nine zones 406 . Each of the nine zones 406 may be further divided into a 9×9 grid of sub-zones 408 , thus the zone grid 400 may have 27×27 sub-zones. The IR camera may capture data relating to the measurement of the temperature for each sub-zone 408 . For example, the IR camera may capture pixilated data points which correspond to the sub-zones 408 . The data points may then be used to create a temperature zone grid, such as the zone heat distribution 118 in FIG. 1 . In an embodiment, the temperatures of the sub-zones 408 for each of the nine zones 406 may be averaged to create a temperature for each of the nine associated zones 406 . For example, the eighty-one temperature sub-zones 408 in a zone 410 may be averaged to create a single temperature for the zone 410 .
[0035] FIG. 5 is a flow chart of a method 500 for controlling and adjusting the heat distribution over a part bed in accordance with another embodiment of the invention. The method 500 begins at a block 502 . At a block 504 , the apparatus is prepared for control and adjustment of the heaters to provide a desired temperature distribution over the powder in the part bed. The preparation may include removing any parts from an additive manufacturing equipment that may interfere with the operation of the heaters. Additionally, the additive manufacturing equipment may include mirrors that direct or position the beam of the laser 106 within the part bed 102 . These mirrors may require removal or relocation during the operation of the heaters. Additional parts may also need to be removed or relocated at the block 504 .
[0036] In addition to removing and relocating parts of the additive manufacturing equipment, the part bed must also be prepared for a simulated process run at the block 504 . This may include selecting part build locations and distribution one or more thin layers of powder across the part bed. For example, the part bed may be prepared by creating a base of a part by completing the first 10 layers of the product(s). Providing a partial product build may improve the operation of the heaters and thus create a more even temperature distribution over the part bed because temperature variances induced by the product formation are taken into account in the process.
[0037] At a block 506 , after the part bed has been heated, the heat distribution is measured with the IR camera. The heat distribution may also be measured by other temperature extracting devices such as by thermocouples or other heat sensing devices. Data is collected from the temperature measurement at the block 506 which is utilized to generate a zone heat distribution at a block 508 . With reference to FIG. 1 , the zone heat distribution 118 may include a grid of temperatures, one for each temperature zone. For example, an IR camera may output pixilated data that is converted to a zone heat distribution at the block 508 .
[0038] At a block 510 , the heat distribution is analyzed. The analysis may be performed by the CPU 120 . For example, an analysis module may be executed by the CPU 120 to calculate any adjustments necessary to the heaters to provide a desired temperature distribution (uniform or non-uniform) across the powder in the part bed. At a decision block 512 , the method 500 determines if the heaters need to be calibrated. The heaters may be adjusted if a zone is outside a predetermined threshold for the zones in relation to a target temperature. For example, the heaters may be adjusted if the zone heat distribution has a variance of temperature greater than two degrees Celsius from the target temperature. Because some temperature variance may always be present across the powder, an adjustment threshold may be established to provide a temperature distribution within acceptable predetermined tolerances.
[0039] If an adjustment is necessary at the decision block 512 , then at a decision block 514 the method 500 selects an adjustment mode via routes A, B, or C. At a block 516 via route A, the energy input to the heaters is adjusted to individually change the input energy of one or more heaters that require adjustment. The energy input may be adjusted by changing the voltage supplied to the heaters by a power source. The electrical current applied to the heaters may also be varied to control the heat emitted from the heaters and directed to the powder in the part bed. Additionally, the energy may be pulsed to the heaters using a variable duty cycle, such that the heat provided by a heater is a function of the pulsating operation of the heater. In one embodiment, each heater is individually controlled and includes a separate power source.
[0040] At a block 518 via route B, the resistance is adjusted to change the resistance of individual heaters and thus alter the heat output of one or more of the heaters. For example, a varistor or rheostat may be utilized to change the resistance of the circuit which includes the heater, thus adjusting the heat output realized across the powder in the part bed.
[0041] At a block 520 via route C, the heaters are repositioned to redirect the heat generated by one or more heaters onto the powder in the part bed. At a decision block 522 , the method 500 determines if another adjustment mode is requested (or required). If so, the method 500 returns to the decision block 514 via route 524 and the heaters are adjusted again. For example, in an iteration of the method 500 , both the resistance at the block 518 and the heater position at the block 520 may be adjusted to control the heaters and generate a target temperature distribution across the powder in the part bed.
[0042] The adjustment modes selected from the decision block 514 may include manual adjustments or automatic (system generated) adjustments. For example, at the block 520 , an operator may reposition the heaters manually or the heaters may be repositioned by actuators in communication with a CPU or other controller and be repositioned automatically. In addition, the adjustments may be performed either open loop or using closed-loop feedback control.
[0043] At the decision block 522 , if it is determined that the adjustment process need not be repeated, the method 500 returns via route 526 to the block 506 to measure the heat distribution again. Moving ahead to the decision block 512 , if the method 500 determines that further control and adjustment of the heaters is not necessary (e.g., all of the zone heat distribution zones are within tolerance), then the method may move to a block 528 and end. The block 528 may include repositioning or reattaching any parts of the additive manufacturing equipment necessary as a result of the actions included in the block 504 .
[0044] FIG. 6 is a flow chart of a closed loop process 600 for controlling and adjusting the heat distribution over a part bed in accordance with another embodiment of the invention. The process 600 begins at a block 602 . At a block 604 , the heat distribution is measured with the IR camera. Data is collected from the measurement at the block 604 which is utilized to generate a zone heat distribution at a block 606 . The data from the zone head distribution is transmitted to the processing device. In some embodiments, the CPU 120 may have a first module (module A) that generates the head distribution and a second module (module B) that receives the output from the first module. The second module may then perform the functionality of a block 610 and analyze the heat distribution obtained at the block 606 . In another embodiment, software executed by the IR camera may generate the zone heat distribution at the block 606 , and then transmit the data to the CPU 120 for analysis.
[0045] At a block 612 , the heater control and adjustment begins. At a decision block 614 , the process 600 determines if the power source of one or more heaters needs adjustment. If the power source requires adjustment, at a block 616 , the energy is adjusted and the process 600 continues to a decision block 618 , otherwise the process continues to the decision block 618 without adjusting the energy output of any of the heaters.
[0046] At a decision block 618 , the process 600 determines if the resistors corresponding to individual heaters need adjustment. If the resistance requires adjustment, at a block 620 , the resistance is adjusted and the process 600 continues to a decision block 622 , otherwise the process continues to the decision block 622 without adjusting the resistance of any of the heaters.
[0047] At a decision block 622 , the process 600 determines if one or more heaters require repositioning. If the heaters need repositioning, at a block 624 , one or more heaters are repositioned and the process 600 continues to a decision block 626 , otherwise the process continues to the decision block 626 without repositioning any of the heaters.
[0048] At the decision block 626 , the process 600 may be repeated via route 628 and therefore provide a closed loop system. For example, the process 600 may be run at specific time iterations or during a point in the process of additive manufacturing, such as right after a new thin layer of powder is applied to the part bed. Therefore, the process 600 may continually adjust the heaters during product formation by continually monitoring the temperature distribution of the powder in the part bed and making the necessary adjustments at the blocks 614 , 620 , and 624 to control and adjust the heaters, and thus, the temperature distribution. If the process is not repeated, such as when the products are complete and no more powder is distributed in the part bed, the process 600 may end at a block 630 .
[0049] In an exemplary control and adjustment of the heaters, the analysis of the zone heat distribution may identify the zone with the lowest temperature. For example, in FIG. 1 , zone 1 and zone 3 in the zone heat distribution 118 depict a temperature of 159° C. The CPU 120 may then create adjustments to the variable resistors 112 (e.g., increase the resistance) and reposition the heaters to reduce the temperature in the other zones to that of the coldest zones (zones 1 and 3 at 159° C.). In a final step, the CPU 120 may increase/decrease the energy to the heaters to raise/lower the temperature of all the heaters to obtain a target temperature.
[0050] Generally, any of the functions described herein can be implemented using software, firmware (e.g., fixed logic circuitry), analog or digital hardware, manual processing, or any combination of these implementations. The terms “module,” “functionality,” and “logic” generally represent software, firmware, hardware, or any combination thereof. In the case of a software implementation, the module, functionality, or logic represents program code that performs specified tasks when executed on processor(s) (e.g., any of microprocessors, controllers, and the like). The program code can be stored in one or more computer readable memory devices. Further, the features and aspects described herein are platform-independent such that the techniques may be implemented on a variety of commercial computing platforms having a variety of processors.
[0051] Methods and systems for controlling and adjusting heat distribution over a part bed in accordance with the teachings of the present disclosure may be described in the general context of computer executable instructions. Generally, computer executable instructions can include routines, programs, objects, components, data structures, procedures, modules, functions, and the like that perform particular functions or implement particular abstract data types. The methods may also be practiced in a distributed computing environment where functions are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, computer executable instructions may be located in both local and remote computer storage media, including memory storage devices.
[0052] In further embodiments, the methods and systems for controlling and adjusting heat distribution over a part bed may allow for a part bed of increased dimensions. For example, in some embodiments, part beds may be approximately 31 centimeters (13 inches) by 36 centimeters (15 inches). This size part bed, however, restricts the size of the part that may be formed utilizing the additive manufacturing techniques. By implementing the methods and systems disclosed herein, any size part bed is obtainable because the temperature distribution may be held at a desired uniform or non-uniform distribution by individually controlling a plurality of heaters to individually heat each zone of the part bed.
[0053] While preferred and alternate embodiments of the invention have 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 these preferred and alternate embodiments. Instead, the invention should be determined entirely by reference to the claims that follow. | Methods and systems for controlling and adjusting heat distribution over a part bed are disclosed. In one embodiment, a technique for providing a calibrated heat distribution over a part bed includes determining the temperature distribution within a part bed, generating a zone heat distribution for a plurality of heat zones from the temperature distribution, analyzing the zone heat distribution to create an adjustment command to calibrate a heater for providing a substantially consistent temperature distribution within the part bed, and adjusting the heater based on the adjustment command. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No. 10/160,528, filed May 31, 2002, pending, which is a continuation of application Ser. No. 09/478,692, filed Jan. 6, 2000, now U.S. Pat. No. 6,398,905, issued Jun. 4, 2002, which is a continuation of application Ser. No. 09/124,329, filed Jul. 29, 1998, now U.S. Pat. No. 6,036,586, issued Mar. 14, 2000.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to polishing methods and apparatus. More particularly, the invention pertains to apparatus and methods for polishing and planarizing semiconductor wafers, optical lenses and the like.
[0004] 2. State of the Art
[0005] In the manufacture of semiconductor devices, it is important that the surface of a semiconductor wafer be planar.
[0006] For high density semiconductor devices having features with extremely small sizes, i.e. less than 1 μm, planarity of the semiconductor wafer is particularly critical to the photolithographic forming of the extremely small conductive traces and the like.
[0007] Methods currently used for planarization include (a) reflow planarization, (b) application of a sacrificial dielectric followed by etch back planarization, (c) mechanical polishing and (d) chemical-mechanical polishing (CMP). Methods (a) through (c) have some applications but have disadvantages for global wafer planarization, particularly when fabricating dense, high speed devices.
[0008] In U.S. Pat. No. 5,434,107 of Paranjpe, a planarization method consists of applying an interlevel film of dielectric material to a wafer—and subjecting the wafer to heat and pressure so that the film flows and fills depressions in the wafer, producing a planar wafer surface. An ultraflat member overlying the dielectric material ensures that the latter forms a flat surface as it hardens. The ultraflat member has a non-stick surface such as polytetrafluoroethylene so that the interlevel film does not adhere thereto.
[0009] In a similar method shown in European Patent Publication No. 0 683 511 A2 of Prybyla et al. (AT&T Corp.), a wafer is covered with a hardenable low-viscosity polymer and an object with a highly planar surface is placed in contact with the polymer until the polymer is cured. The object is separated from the polymer, which has cured into a highly planar surface.
[0010] The planarization method of choice for fabrication of dense integrated circuits is typically chemical-mechanical polishing (CMP). This process comprises the abrasive polishing of the semiconductor wafer surface in the presence of a liquid or slurry.
[0011] In one form of CMP, a slurry of an abrasive material, usually combined with a chemical etchant at an acidic or alkaline pH, polishes the wafer surface in moving compressed planar contact with a relatively soft polishing pad or fabric. The combination of chemical and mechanical removal of material during polishing results in superior planarization of the polished surface. In this process it is important to remove sufficient material to provide a smooth surface, without removing an excessive quantity of underlying materials such as metal leads. It is also important to avoid the uneven removal of materials having different resistances to chemical etching and abrasion.
[0012] In an alternative CMP method, the polishing pad itself includes an abrasive material, and the added “slurry” may contain little or no abrasive material, but is chemically composed to provide the desired etching of the surface. This method is disclosed in U.S. Pat. No. 5,624,303 of Robinson, for example.
[0013] Various methods for improving wafer planarity are directed toward the application of interlayer materials of various hardness on the wafer surface prior to polishing. Such methods are illustrated in U.S. Pat. No. 5,618,381 of Doan et al., U.S. Pat. No. 5,639,697 of Weling et al., U.S. Pat. No. 5,302,233 of Kim et al., U.S. Pat. No. 5,643,837 of Hayashi, and U.S. Pat. No. 5,314,843 of Yu et al.
[0014] The typical apparatus for CMP polishing of a wafer comprises a frame or base on which a rotatable polishing pad holder or platen is mounted. The platen, for example, may be about 20-48 inches (about 50-122 cm.) or more in diameter. A polishing pad is typically joined to the platen surface with a pressure-sensitive adhesive (PSA).
[0015] One or more rotatable substrate carriers are configured to compress e.g. semiconductor wafers against the polishing pad. The substrate carrier may include non-stick portions to ensure that the substrate, e.g. wafer, is released after the polishing step. Such is shown in U.S. Pat. No. 5,434,107 of Paranjpe and U.S. Pat. No. 5,533,924 of Stroupe et al.
[0016] The relative motion, whether circular, orbital or vibratory, of the polishing pad and substrate in an abrasive/etching slurry may provide a high degree of planarity without scratching or gouging of the substrate surface, depending upon wafer surface conditions. Variations in CMP apparatus are shown in U.S. Pat. No. 5,232,875 of Tuttle, U.S. Pat. 5,575,707 of Talieh, U.S. Pat. No. 5,624,299 of Shendon, U.S. Pat. No. 5,624,300 of Kishii et al., U.S. Pat. No. 5,643,046 of Katakabe et al., U.S. Pat. No. 5,643,050 of Chen, and U.S. Pat. No. 5,643,406 of Shimomura et al.
[0017] In U.S. Pat. No. 5,575,707 of Talieh et al., a wafer polishing system has a plurality of small polishing pads which together are used to polish a semiconductor wafer.
[0018] As shown in U.S. Pat. No. 5,624,304 of Pasch et al., the polishing pad may be formed in several layers, and a circumferential lip may be used to retain a desired depth of slurry on the polishing surface.
[0019] A CMP polishing pad has one or more layers and may comprise, for example, felt fiber fabric impregnated with blown polyurethane. Other materials may be used to form suitable polishing pads. In general, the polishing pad is configured as a compromise polishing pad—that is a pad having sufficient rigidity to provide the desired planarity, and sufficient resilience to obtain the desired continuous tactile pressure between the pad and the substrate as the substrate thickness decreases during the polishing process.
[0020] Polishing pads are subjected to stress forces in directions both parallel to and normal to the pad-substrate interfacial surface. In addition, pad deterioration may occur because of the harsh chemical environment. Thus, the adhesion strength of the polishing pad to the platen must be adequate to resist the applied multidirectional forces during polishing, and chemical deterioration should not be so great that the pad-to-platen adhesion fails before the pad itself is in need of replacement.
[0021] Pores or depressions in pads typically become filled with abrasive materials during the polishing process. The resulting “glaze” may cause gouging of the surface being polished. Attempts to devise apparatus and “pad conditioning” methods for removing such “glaze” materials are illustrated in U.S. Pat. No. 5,569,062 of Karlsrud and U.S. Pat. No. 5,554,065 of Clover.
[0022] In any case, polishing pads are expendable, having a limited life and requiring replacement on a regular basis, even in a system with pad conditioning apparatus. For example, the working life of a typical widely used CMP polishing pad is about 20-30 hours.
[0023] Replacement of polishing pads is a difficult procedure. The pad must be manually pulled from the platen, overcoming the tenacity of the adhesive which is used. The force required to manually remove a 30-inch diameter pad from a bare aluminum or ceramic platen may exceed 100 lbf (444.8 Newtons) and may be as high as 150 lbf (667.2 Newtons) or higher. Manually applying such high forces may result in personal injury as well as damage to the platen and attached machinery.
BRIEF SUMMARY OF THE INVENTION
[0024] The invention comprises the application of a permanent, low adhesion, i.e. “non-stick,” coating of uniform thickness to the platen surface. Exemplary of such coating materials are fluorinated compounds, in particular fluoropolymers including polytetrafluoroethylene (PTFE) sold under the trademark TEFLON by DuPont, as well as polymonochlorotrifluoroethylene (CTFE) and polyvinylidene fluoride (PVF 2 ). The coating retains its tenacity to the underlying platen material, and its relatively low adhesion to other materials, at the temperatures, mechanical forces, and chemical action encountered in CMP processes.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0025] The invention is illustrated in the following figures, wherein the elements are not necessarily shown to scale:
[0026] FIG. 1 is a perspective partial view of a polishing apparatus of the prior art;
[0027] FIG. 2 is a cross-sectional view of a portion of a polishing apparatus of the prior art, as taken along line 2 - 2 of FIG. 1 ;
[0028] FIG. 3 is a cross-sectional view of a portion of a polishing apparatus of the invention;
[0029] FIG. 4 is a cross-sectional view of a portion of a platen and polishing pad of the invention, as taken along line 4 - 4 of FIG. 3 ;
[0030] FIG. 5 is a top view of a polishing platen and pad of another embodiment of the invention; and
[0031] FIG. 6 is a cross-sectional view of a portion of a platen and polishing pad of the invention, as taken along line 6 - 6 of FIG. 5 .
DETAILED DESCRIPTION OF THE INVENTION
[0032] Portions of a typical prior art chemical-mechanical polishing (CMP) machine 10 are illustrated in drawing FIGS. 1 and 2 . A platen 20 has attached to its upper surface 12 a polishing pad 14 by a layer of adhesive 16 . If it is desired to rotate platen 20 , its shaft 18 , attached to the platen 20 by flange 48 , may be turned by a drive mechanism, such as a motor and gear arrangement, not shown.
[0033] A substrate 30 such as a semiconductor wafer or optical lens is mounted on a substrate carrier 22 which may be configured to be moved in a rotational, orbital and/or vibratory motion by motive means, not shown, through shaft 24 . In a simple system, shafts 18 and 24 may be rotated in directions 26 and 28 as shown. The substrate 30 is held in the carrier 22 by friction, vacuum or other means resulting in quick release following the polishing step. A layer 38 of resilient material may lie between the substrate 30 and carrier 22 . The surface 32 of the substrate 30 which is to be planarized faces the polishing surface 34 of the pad 14 and is compressed thereagainst under generally light pressure during relative movement of the platen 20 (and pad 14 ).
[0034] In chemical-mechanical polishing (CMP), a polishing slurry 40 is introduced to the substrate-pad interface 36 to assist in the polishing, cool the interfacial area, and help maintain a uniform rate of material removal from the substrate 30 . The slurry may be introduced e.g. via tubes 42 from above, or may be upwardly introduced through apertures, not shown, in the polishing pad 14 . Typically, the slurry 40 flows as a layer 46 on the pad polishing surface 34 and overflows to be discarded.
[0035] Upward removal of a polishing pad 14 from the platen surface 12 is generally a difficult operation requiring high removal forces. Pad replacement is necessary on a regular basis, and the invention described herein and illustrated in drawing FIGS. 3 through 6 makes pad replacement easier, safer and faster.
[0036] Turning now to drawing FIGS. 3 and 4 , the prior art polishing apparatus of drawing FIG. 2 is shown with a platen 20 modified in accordance with the invention. Parts are numbered as in drawing FIG. 2 , with the modification comprising a permanent coating 50 of a “non-stick” or low-adhesion material applied to the upper surface 12 of the platen 20 , along coating/adhesive interface 54 . The polishing pad 14 is then attached to the coating 50 using a pressure-sensitive adhesive (PSA) 16 . It is common practice for manufacturers of polishing pads to supply pads with a high-adhesion PSA already fixed to the attachment surface 44 of the pads. It has been found that the adhesion of polishing pads 14 to certain low-adhesion coatings 50 with conventional high adhesion adhesives results in a lower release force, yet the bond strength is sufficient to maintain the integrity of the polishing pads 14 during the polishing operations. Typically, variables affecting the release force include the type and surface smoothness of the coating 50 , the type and specific adhesion characteristics of the adhesive material 16 , and pad size.
[0037] Referring to drawing FIGS. 5 and 6 , depicted is another version of the platen 20 which is coated with a low-adhesion coating 50 in accordance with the invention. In this embodiment, the platen 20 includes a network of channels 58 , and slurry 40 is fed thereto through conduits 60 . The low-adhesion coating 50 covers the platen 20 and, as shown, may extend into at least the upper portions of channels 58 . Apertures 64 through the coating 50 match the channels 58 in the platen 20 . The polishing pad 14 and attached pressure-sensitive adhesive (PSA) 16 have through-apertures 62 through which the slurry 40 may flow upward from channels 58 and onto the polishing surface 34 of the pad 14 .
[0038] The surface area of coating 50 to which the adhesive 16 may adhere is reduced by the apertures 64 . This loss of contact area between adhesive 16 and platen coating 50 may be compensated by changing the surface smoothness of the coating or using an adhesive material with a higher release force.
[0039] Materials which have been found useful for coating the platen 20 include coatings based on fluoropolymers, including polytetrafluoroethylene (PTFE or “Teflon”), polymonochloro-trifluoroethylene (CTFE) and polyvinylidene fluoride (PVF 2 ). Other materials may be used to coat the upper surface 12 of platen 20 , provided that the material has the desired adherence, i.e. release properties, with available adhesives, may be readily cleaned, and has a long life in the mechanical and chemical environment of polishing.
[0040] Various coating methods may be used. The platen 20 may be coated, for example, using any of the various viable commercial processes, including conventional and electrostatic spraying, hot melt spraying, and cementation.
[0041] In the application of one coating process to a modification of the platen 20 , the upper surface 12 of the platen is first roughened to enhance adhesion. The coating material 50 is then applied to the upper surface 12 by a wet spraying or dry powder technique, as known in the art. In one variation of the coating process, white-hot metal particles, not shown, are first sprayed onto the uncoated base surface and permitted to cool, and the coating 50 is then applied. The metal particles reinforce the coating 50 of low-adhesion material which is applied to the platen 20 .
[0042] The result of this invention is a substantial reduction in release force between polishing pad 14 and platen 20 to a level at which the pad may be removed from the platen with minimal effort, yet the planar attachment of the pad to the platen during polishing operations will not be compromised. The particular combination(s) of coating 50 and adhesive material 16 which provide the desired release force may be determined by testing various adhesive formulations with different coatings.
[0043] Another method for controlling the release force is the introduction of a controlled degree of “roughness” in the coating surfaces 52 (including surfaces of fluorocarbon materials) for changing the coefficient of friction. The adhesion of an adhesive material 16 to a coating 50 may be thus controlled, irrespective of the pad construction, size or composition.
[0044] The use of a coating 50 of the invention provides useful advantages in any process where a polishing pad 14 must be periodically removed from a platen 20 . Thus, use of the coating 50 is commercially applicable to any polishing method, whether chemical-mechanical polishing (CMP), chemical polishing (CP) or mechanical polishing (MP), where a polishing pad 14 of any kind is attached to a platen 20 .
EXAMPLE
[0045] A piece of flat aluminum coated with polytetrafluoroethylene (PTFE) was procured. The particular formulation of PTFE was Malynco 35011 Black Teflon™, applied to the aluminum.
[0046] Conventional CMP polishing pad samples were obtained in a size of 3.7×4.2 inches (9.4×10.67 cm.). The area of each pad was 15.54 square inches (100.3 square cm.). These pads were identified as SUBA IV psa 2 adhesive pads and were obtained from Rodel Products Corporation of Scottsdale, Ariz.
[0047] The polishing pads included a polyurethane-based pressure-sensitive adhesive (PSA 2 ) on one surface. The pads were placed on the coated aluminum, baked at 53° C. for two hours under slight compression, and cooled for a minimum of 45 minutes, thereby bonding the pads to the PTFE surface.
[0048] Samples of the same pad material were similarly adhered to an uncoated aluminum surface of a polishing platen for comparison as test controls.
[0049] Tests were conducted to determine the force required to remove each pad from the surface coating and the uncoated surfaces. The average measured removal forces were as follows:
[0050] Removal force from Malynco 35011 Black Teflon™ coated aluminum: 1.08 lbf.
[0051] Removal force from uncoated aluminum: 11.5 lbf.
[0052] Extrapolation to actual production size platens of 30 inch diameter indicates that pad removal forces may be reduced from about 100-150 lbf. (about 444.8-667.2 Newtons) to about 15 lbf. to about 25 lbf. (about 66 to 112 Newtons). This force is sufficient to maintain pad-to-platen integrity during long-term polishing but is a significant reduction in the force required for pad removal and replacement.
[0053] It is apparent to those skilled in the art that various changes and modifications, including variations in pad type and size, platen type and size, pad removal procedure, etc. may be made to the polishing apparatus and method of the invention as described herein without departing from the spirit and scope of the invention as defined in the following claims. | An improvement in a polishing apparatus for planarizing substrates comprises a tenacious coating of a low-adhesion material to the platen surface. An expendable polishing pad is adhesively attached to the low-adhesion material, and may be removed for periodic replacement at much reduced expenditure of force. Polishing pads joined to low-adhesion materials such as polytetrafluoroethylene (PTFE) by conventional adhesives resist distortion during polishing but are readily removed for replacement. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to tape recorders and, more particularly, is directed to an improved apparatus to change the operating modes of a tape recorder by means of a feather touch push button operating through a trigger motor and which is suitable for use in battery operated portable tape recorders.
2. Description of the Prior Art
In prior art mode changing mechanisms for tape recorders solenoids are employed for each selected mode of operation, for example to move a head carriage assembly or for pinch roller displacement. These solenoids when activated require a constant current supply during the record or reproducing mode of the recorder. Since the solenoids used in these recorders are relatively large in order to maintain the head and pinch roller in operative position the current drain is inordinately large.
To obviate the disadvantage of the current drain incident with the use of solenoids, there has been proposed a mode changing apparatus wherein the solenoid is used only to effect a light triggering operation, i.e., the solenoid acts only as a trigger to convey the rotational output of a motor to an operating mode changing apparatus. Such a mechanism is disclosed in U.S. Pat. No. 4,167,764. The mechanism in the aforesaid patent has successfully reduced current loads and has permitted use of smaller solenoids than were employed in mode changing mechanisms theretofore so that power consumption was reduced.
However, in general where a portable tape recorder operating on dry cell batteries as a power supply is used, the reduction in the power consumption using the mechanism of the aforesaid patent is still not enough in order to obtain prolonged battery life.
OBJECTS AND SUMMARY OF THE INVENTION
Accordingly, it is an object of this invention to provide a mode changing apparatus for a tape recorder which is operable to effect mode change without use of solenoids and at a low power drain.
It is a further object of the present invention to provide a mode changing apparatus of the feather touch push button type wherein the slight depression of the feather touch push button initiates a trigger response to mesh a drive gear with the mode change apparatus to initiate a mode change.
A still further object of the present invention is to provide a mode changing apparatus for use in portable battery operated tape recorders which is relatively compact, light in weight and inexpensive to construct.
In accordance with an aspect of this invention a mode changing apparatus for a tape recorder is provided with a loading gear member made of a permanent magnet material and having a cutout therein. A continuously rotating drive gear operatively connected to the tape recorder drive motor is disposed adjacent the loading gear and rotates within the cutout portion of the loading gear so that the drive gear is not in meshing engagement with the loading gear. An excitable electromagnet is provided about the loading gear so that when a trigger current is introduced in the electromagnet, the magnetic flux induced rotates the loading gear to mesh it with the drive gear which drives the loading gear to effect a mode change in the tape recorder.
The above and other objects, features and advantages of the invention will be more readily apparent in the following detailed description of illustrative emobodiments thereof which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan diagrammatic representation of the drive gear and loading gear of the embodiment of the mode change apparatus of the present invention;
FIG. 2 is an elevational view of the apparatus shown in FIG. 1;
FIG. 3 is a diagrammatic representation of the electromagnetic system used as a trigger device in the mode changing apparatus of the present invention;
FIG. 4 is a top plan diagrammatic representation similar to FIG. 1 of an alternate embodiment of the present invention;
FIG. 5 is a diagrammatic elevational view of another embodiment of the loading gear and electromagnet system of the present invention;
FIG. 6 is a diagrammatic plan view of the embodiment of FIG. 5; and
FIG. 7 is a plan view of the mode changing apparatus of the present invention depicted in the environment of a tape recorder.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1 to 3 of the drawings, there is shown an assembly for the trigger mechanism to initiate a mode change in a tape recorder which includes a loading gear member 1 made of a permanent magnet material. Gear 1 includes a toothed peripheral segment 2 and a cutout segment 3 without gear teeth. Gear 1 is rotatably fixed on a shaft 4 mounted on the player chassis 5. A yoke 6 with yoke arms 7 and 8 disposed about loading gear 1 and a coil bobin 9 having an exciting coil 10 wound thereabout is provided for triggering a mode changing operation.
Loading gear 1 is magnetized in the direction of the thickness of gear 1 as indicated in FIG. 3 and when coil 10 is energized by a pulsed d.c. current so as to generate a flux Φ A in yoke 6 loading gear 1 is driven to rotate in a direction indicated by the arrow A in FIG. 1. When coil 10 is energized by a pulsed d.c. current of opposite polarity so as to generate a flux Φ B in yoke 6, loading gear 1 is driven to rotate in the opposite direction indicated by the arrow B in FIG. 1.
Upon rotation of gear 1 responsive to the pulsed excitation of coil 10, the toothed segment 2 of gear 1 moves into meshing engagement with a drive gear 11 driven by a drive motor 12, which may be the main rotating power source for the tape recorder. Thus, cutout portion 3 of loading gear 1 should be located in a position adjacent drive gear 11 but not in meshing engagement therewith until loading gear 1 is rotated by excitation of coil 10.
Upon engagement of loading gear 1 with drive gear 11, the drive gear 11 under the rotative force of motor 12 supplies the power source to effect a mode changing operation, as will be explained more fully hereinbelow. Thus, to initiate a mode changing operation, only a triggering pulsed current to coil 10 need be supplied sufficient to rotate loading gear 1 into meshing engagements with drive gear 11.
Reference is now made to FIG. 4 for an alternate embodiment for the loading gear of the present invention. In this embodiment the loading gear 13 made of a permanent magnet material has a full gear toothed periphery 14 which is in meshing engagement with a gear 15 disposed on a shaft 16 rotatably mounted on the chassis. A gear 17 having a cutout segment 18 is also secured to shaft 16 and rotates as gear 15 and shaft 16 are rotated. Gear 17 with cutout 18 is disposed adjacent a drive gear (not shown) as in the embodiment of FIG. 1.
Thus as the coil about bobbin 9 is excited, loading gear 13 is driven to drive gear 17 into meshing engagement with the drive gear. With the embodiment of FIG. 4, the gear members 15 and 17 may be made of nonmagnetic materials such as synthetic resins and the like.
FIGS. 5 and 6 show another alternate embodiment where a U-shaped yoke 19 is disposed about a loading gear 20 of magnetic material having a cutout segment 21 and an extending shoulder segment 22 disposed within the arms of yoke 19. Gear 20 is fixed to a shaft 23 rotatably disposed within bearings 24 and 25 at each end. A coil 26 is provided about yoke 19 to induce flux to rotate loading gear 20. As in the other embodiments, rotation of loading gear 20 results in the meshing engagement of the gear teeth of gear 20 with a drive gear (not shown).
Reference is now made to FIG. 7 for a description of the mode changing apparatus of the present invention where any of the embodiments of FIGS. 1 to 6 may be employed to rotate the loading gear to initiate a mode changing operation.
As shown in FIG. 7, a loading gear 30 having a cutout segment 31 is provided for rotation by excitation of a coil 32 in the same manner described above. A drive gear 33 is positioned adjacent cutout 31 to be engageable with the teeth on loading gear 30 when loading gear 30 is rotated upon excitation of its coil 32. Drive gear 33 is driven by a gear 34 fixed to capstan shaft 35.
A positioning spring 36 is provided having one end 37 bearing against a loading pin 38 extending from loading gear 30 (see FIG. 2 as well) to maintain loading gear 30 in its disengaged position with respect to drive gear 33 until a triggering pulse of current rotates loading gear 30 into engagement with the drive gear.
Loading pin 38 also acts to move a loading base plate 39 when loading gear 30 is engaged and driven by drive gear 33. Loading base plate 39 is disposed for reciprocating movement within the recorder by being provided with guide slots 40 and 41 which receive guide pins 42 and 43, respectively, extending from the chassis and by a guide pin 44 bearing against a lateral edge 45 of loading base plate 39.
Loading base plate 39 is normally urged downwardly, as viewed in FIG. 7, by a coiled spring 46 fixed at one end to the base plate 39 and at its other end to the chassis. Loading base plate 39 also includes a cutout segment 47 within which is disposed one end 48 of a lock lever 49 which is urged by a spring 50 to move lock lever 49 into engagement with loading base plate 39 in its upward position, as viewed in FIG. 7, after it has been moved responsive to the rotation of loading gear 30 due to the engagement of the loading gear with drive gear 33.
Before loading, i.e. before a pulse trigger current excites coil 32 to rotate loading gear 30, drive gear 33 is rotated by the main power source but, since cutout 31 confronts drive gear 33, no rotative force is imparted to loading gear 30. When a trigger pulse for clockwise (as viewed in FIG. 7) rotational displacement for loading gear 30 is initiated responsive to a light feather touch to an operating mode selecting push button (not shown) for the recorder, loading gear 30 is rotated into meshing engagement with driven gear 33 and is rotated by driven gear 33. With this driven rotation of loading gear 30, loading pin 38 moves into contact with loading base plate 39 and the base plate is moved upwardly (as viewed in FIG. 7) by the action of the rotating loading pin 38 in contact with loading base plate 39. The loading base plate 39 is subjected to its maximum displacement with one half revolution of loading gear 30, i.e. when loading pin 38 is displaced 180° from the position shown in FIG. 7. At this juncture, a bent tab 51 extending from loading base plate 39 is engaged by an extending tab 52 on lock lever 49 to lock the loading base plate 39 in its upper displaced position. Loading gear 30 continues to be driven by drive gear 33 until it returns to its initial position where cutout 31 confronts drive gear 33 and no further rotative force is imparted to the loading gear 30.
With the upward (as viewed in FIG. 7) movement of loading base plate 39 a head carriage support plate 53 is moved to a recording and/or reproducing position through the urging of a coil spring 54 connected at one end to a projection 55 on the loading base plate 39 and a projection 56 on the head carriage support plate 53.
The same upward movement (as viewed in FIG. 7) of loading base plate 39 and head carriage support plate 53 moves a pinch roller 57 which is rotatably mounted on a pinch roller arm 58 into contact with capstan shaft 35. Pinch roller arm 58 is pivotally supported on a guide post 59 and is urged into engagement with capstan 35, to pinch magnetic tape therebetween, by the action of spring 54 urging head carriage support plate 53 and a spring 60 acting against the pinch roller arm 58.
To release the lock on loading base plate 39, a trigger pulse of current is again applied rotating loading gear 30 into engagement with drivegear 33 to rotate loading gear 30 until loading pin 38 again contacts loading base plate 39. This contact moves loading base plate 39 slightly releasing the lock from lock lever 49 and loading base plate 39 returns to its initial disengaged position under urging of spring 46. With this movement of loading base plate 39 head carriage support plate 53 and pinch roller 57 also retract from the engaged play position.
It is thus seen that the present invention provides a compact single motor tape recorder where selected operating modes are effected by a feather touch mode selecting push button without requiring use of solenoids. As is apparent from the foregoing description, the mode selecting operation results from the application of a pulsed trigger signal of short duration to initiate displacement of a loading gear member into operative engagement with the main drive system powered by the recorder's single motor. Thus an external signal of low power drain effectively provides a limited degree of rotational movement. Use of the low power signal has the advantage that rotational direction can be freely selected permitting a wide range of application for the trigger mechanism of this invention which is more advantageous than prior art devices using a single direction input from a solenoid type device.
In addition, it is also readily apparent that the changeover mechanism of the present invention can be readily adapted to varying size depending upon the size or characteristic of the operating mechanism employed and that the changeover mechanism is relatively simple to manufacture and assemble and can be manufactured at relatively reasonable cost. | A mode changing apparatus for a tape recorder to initiate a change in mode including a loading gear having at least a portion magnetized in N and S poles and an electromagnet adjacent to the magnetized portion of the loading gear. When a trigger signal is applied to the electromagnet responsive to the selection of a mode of operation for the tape recorder, the loading gear is brought into meshing engagement with a drive gear. The drive gear is driven and disposed so it does not mesh with the loading gear until the electromagnet is energized. Once the electromagnet is energized to engage the drive gear and loading gear the rotation of the loading gear effects the mode change of the tape recorder. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] Reference is made to the co-pending, commonly assigned, U.S. Provisional Patent Application Ser. No. 60/540,529 filed on Jan. 30, 2004, entitled: PREPARATION OF A TONER FOR REPRODUCING A METALLIC HUE AND THE TONER, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a toner and a process for preparing a toner, for reproduction of a metallic, preferably golden or silvery, hue by a printing process, especially for electrophotography.
BACKGROUND OF THE INVENTION
[0003] Printing processes serve not only to reproduce and transmit objective information, but also to convey esthetic impressions, for example when coffee-table books are printed or else in pictorial advertising. An immense problem here is posed in particular by the reproduction of metallic hues. Metallic hues are only imperfectly reproducible by a color mixture formed from primary colors, especially the colors cyan, magenta, yellow, and black (CMYK). A gold tone is particularly difficult to reproduce by means of such a color mixture. It has therefore already been proposed to incorporate metallic pigments or particles in the printing ink in order that a metallic color may be brought about directly. But in the case of toners, where magnetic and/or electrical and especially electrostatic properties are decisive, this is particularly problematic, since metallic constituents may have an adverse effect on these properties. Yet there have already been proposals to imbue toners with metallic constituents. For instance, U.S. Pat. No. 5,180,650, issued on Jan. 19, 1993, discloses providing a toner composition, which contains lightly colored metallic constituents, such as copper, silver or gold for example, in a coating, which in turn has been provided with an over-coating comprised of a metal halide.
[0004] But the appearance of prints in particular may be adversely affected by chemical reactions of the metallic constituents due to the halides, which can promote oxidations of the constituents for example. For instance, the tarnishing with which everyone is familiar from copper or silver objects may occur, making the metallic quality unattractive or disappear completely. Moreover, these toners are only lightly metallically colored, which is insufficient to reproduce a gold tone in printed matter. Further, when metallic constituents are incorporated in toners using conventional manufacturing processes, these metallic flakes are randomly oriented throughout the toner particles. This random orientation leads to the loss of metallic hue, and causes a dark appearance when such toners are fixed to a receiver sheet using heated rollers.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to preserve a congeneric process and/or a congeneric toner with regard to its metallic hue and at the same time not to impair the essential properties of the toner for the printing process in which it is to be used, especially for electrophotography or electrography. It shall preferably be possible to fuse the toner to the printed stock in a non-contact manner, especially with the aid of microwaves, without disruption due to metallic constituents in the toner.
[0006] This object can be achieved according to the present invention by several methods. One involves first providing a metallic pigment with a coating of silicate, titanate, or aluminate and subsequently with an organic layer and combining the thus obtained particle with toner material including for example of: polymer, charge control agent, optional colorant, and fumed metal oxide like silica, titania, or aluminia hydrophobically surface coated. Another approach involves providing a coating of an organic layer over the metallic pigment, and combining the resulting particle with toner material consisting of polymer resin, optional charge control agent, and optional fumed metal oxide particles that have been hydrophobized with a coating such as silica, titania, or alumina.
[0007] In further developments of the present invention, the organic layer utilizes at least one aliphatic acid, stearic acid, at least one amide of at least one acid, at least one salt of at least one acid, at least one olefinic material and/or at least one natural or synthetic wax. However, the use of stearic acid could give rise to the problem that the stearic acid will plasticize the toner material, and so would need to be done with particular care. The organic layer may include at least one polymer organic layer, such as a polyester, over the silicate, titanate, or aluminate layer. The organic layer could also include any of the polymers that are typically used as toner resins, as described in more detail hereinbelow. In addition, the metallic pigment may have only the organic layer as a coating, which may include at least one polymer, such as polyester.
[0008] Otherwise, the process of the present invention can conform to any well-known process for preparing dry toners wherein pigments are conventionally incorporated in a toner core, i.e., for example by compounding, classifying and/or grinding. Instead of embedding pigments in a toner core it is also possible, for example, to utilize a shell construction wherein a pigment is applied to the surface of a toner body, especially as part of a coating, optionally alone or mixed with other ingredients, for example with polymers, waxes, or charge control agents. Illustrative references are U.S. Pat. No. 5,298,356, issued on Mar. 29, 1994 and/or U.S. Pat. No. 6,110,633, issued on Aug. 29, 2000, the disclosures of which are hereby incorporated by reference thereto.
[0009] Finally the inventive toner maybe coated with an additional component on the surface consisting of hydrophobic fumed metal oxides like silica, aluminia, or titania in concentrations of about 0.1% to about 3%.
[0010] The toners may be alternatively produced by so-called chemical toner processes, called as well “chemically prepared toners”, “polymerized toners” or “in situ toners”. The toners are not produced by grinding but by controlled growth. Chemical process to be used are, among others, suspension polymerization (e.g., DE 4202461, DE 4202462); emulsion aggregation (e.g., U.S. Pat. No. 5,604,076, issued on Feb. 18, 1997); micro-encapsulation (e.g., DE 10011299); dispersion (e.g., U.S. Publication No. 2003/0087176 A1, published on May 8, 2003); or chemical milling (e.g., proceedings of IS&T NIP 17: International Conference on Digital Printing Technologies, IS&T: The Society for Imaging Science and Technology, 7003 Kilworth Lane, Springfield, Va. 22151 USA ISBN: 0-89208-234-8, p. 345). The disclosures of al the above references are hereby incorporated by reference thereto.
[0011] In a further development of the present invention, the pigment is made platelet shaped. This is particularly advantageous for its adduction to a surface of a (larger) toner material particle.
[0012] Preferably, the metallic pigment can be coated with the silicate with the aid of a so-called sol-gel process. This can provide a particularly thin coating. It can be envisaged to this end to use stearic acid as lubricant and/or that the pigment is dispersed in a mixture of ethanol, water and a silica, titania, or aluminia precursor. The silica precursor may be tetraethoxysilanes. The quantity of the silanes may of course be dependent on the particle size of the pigment. Preferably, a catalyst is used in addition.
[0013] In a further embodiment, the mixture is heated to speed a reaction in which the silica, titania, or aluminia precursor is hydrolyzed and reacts to form a silicate, titanate, or aluminate, which deposits as a thin film on the pigment. A filtration may then be carried out to filter off undesirable by-products, for example the catalyst, metal compounds, or stearic acid.
[0014] It is possible to carry out drying and evaporation of solvent residues to achieve a pulverulent residue as a substance, which contains the silicate-coated pigment.
[0015] Preferably, the silicate, titanate, or aluminate comprises about 2% to about 10% of the weight of the metallic pigment.
[0016] The toner material can be clear/colorless or transparent or have an inherent color. When the toner material has an inherent color, this can lead to interesting color-varying effects with the metallic hue in a print or change the metallic hue as a whole.
[0017] The invention, and its objects and advantages, will become more apparent in the detailed description of the preferred embodiments presented below.
DETAILED DESCRIPTION OF THE INVENTION
[0018] In a preferred embodiment of the process according to the present invention, the pigment is about 7 μm in size and toner particles of the toner material are about 6-12 μm in size. As mentioned earlier, pigments may each be disposed on one surface of a toner particle of the toner material.
[0019] The organic layer may include or consist of a polymer. Useful polymers include vinyl polymers, such as homopolymers and copolymers of styrene. Styrene polymers include those containing 40 to 100 percent by weight of styrene, or styrene homologs, and from 0 to 40 percent by weight of one or more lower alkyl acrylates or methacrylates. Other examples include fusible styrene-acrylic copolymers that are covalently lightly crosslinked with a divinyl compound such as divinylbenzene. Binders of this type are described, for example, in U.S. Re. Pat. No. 31,072, which is incorporated in its entirety by reference wherein. Preferred binders comprise styrene and an alkyl acrylate and/or methacrylate, and the styrene content of the binder is preferably at least about 60% by weight.
[0020] Copolymers rich in styrene such as styrene butylacrylate and styrene butadiene are also useful as binders, as are blends of polymers. In such blends, the ratio of styrene butylacrylate to styrene butadiene can be 10:1 to 1:10. Ratios of 5:1 to 1:5 and 7:3 are particularly useful. Polymers of styrene butylacrylate and/or butylmethacrylate (30 to 80% styrene) and styrene butadiene (30 to 80% styrene) are also useful binders.
[0021] Styrene polymers include styrene, alpha-methylstyrene, para-chlorostyrene, and vinyl toluene. Alkyl acrylates or methylacrylates or monocarboxylic acids having a double bond selected from acrylic acid, methyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenylacrylate, methylacrylic acid, ethyl methacrylate, butyl methacrylate and octyl methacrylate and are also useful binders.
[0022] Also useful are condensation polymers such as polyesters and copolyesters of aromatic dicarboxylic acids with one or more aliphatic diols, such as polyesters of isophthalic or terephthalic acid with diols such as ethylene glycol, cyclohexane dimethanol, and bisphenols. Other useful resins include polyester resins, such as may be obtained by the co-polycondensation polymerization of a carboxylic acid component comprising a carboxylic acid having two or more valencies, an acid anhydride thereof or a lower alkyl ester thereof (e.g., fumaric acid, maleic acid, maleic anhydride, phthalic acid, terephthalic acid, trimellitic acid, or pyromellitic acid), using as a diol component a bisphenol derivative or a substituted compound thereof. Specific examples are described in U.S. Pat. Nos. 5,120,631; 4,430,408; and 5,714,295, all incorporated herein by reference, and include propoxylated bisphenol—A fumarate, such as Finetone® 382 ES from Reichold Chemicals, formerly Atlac® 382 ES from ICI Americas Inc.
[0023] A useful binder can also be formed from a copolymer of a vinyl aromatic monomer with a second monomer selected from either conjugated diene monomers or acylate monomers such as alkyl acrylate and alkyl methacrylate.
[0024] The metallic pigment preferably has a gold tone. This could be achieved with genuine gold. However, it is preferable to use a pigment, which contains copper and zinc, preferably in the form of an alloy, which could thus be referred to as brass or bronze, depending on the composition. Preferably, the ratio of copper and zinc fractions in the alloy varies from about 90:10 to about 70:30. As the zinc fraction in the alloy increases, the metallically golden hue changes from a more reddish to a more yellowish or even greenish gold tone. The color of the gold tone may possibly be intensified through a controlled oxidation of the metal.
[0025] The metallic pigment could alternatively have, for example, a silver tone which could result from the pigment containing among other possibilities, aluminum.
[0026] The present invention further provides a toner for reproduction of a metallic, preferably golden or silvery, hue by a printing process, especially for electrophotography, preferably prepared by the above-described process and; distinguished by at least one particle which comprises at least one metallic pigment, which has optionally been provided with a coat of silicate, and there-over with an organic layer. The advantages of such a toner have already been described in connection with the process of the present invention. The further developments of the toner according to the present invention, which may specifically be contemplated as particular embodiments on their own or combined, envisage that the organic layer contains: at least one aliphatic acid; that the organic layer contains stearic acid, that the organic layer contains at least one amide of at least one acid, that the organic layer contains at least one salt of at least one acid, that the organic layer contains at least one olefinic material, that the organic layer contains at least one wax, that the wax is a natural wax, that the wax is a synthetic wax, that the pigment is platelet shaped, that the pigment has been coated with the silicate by a sol-gel process, that the toner is a pulverulent toner, that the silicate, titanate, or aluminate comprises about 2% to about 10% of the weight of the metallic pigment, that the pigment has been admixed to a toner material which is clear or transparent, that the pigment has been admixed to a toner material which has an inherent color, that the pigment is about 7 μm in size and that toner particles of the toner material are about 6-12 μm in size, that pigments are each disposed on a surface of a toner particle of the toner material, that the organic layer comprises a polymer, that the pigment is gold colored, that the pigment contains copper and zinc, that the pigment contains copper and zinc as constituents of an alloy, that the ratio of copper and zinc fractions in the alloy varies from about 90:10 to about 70:30, that the pigment is silver colored, and/or that the pigment contains aluminum.
[0027] The inventive toner maybe applied to a substrate by a digital printing process, preferably an electrostatic printing process, more preferably by an electrophotographic printing process as described in L. B. Schein, Electrophotography and Development Physics, 2 nd Edition, Laplacian Press, Morgan Hill, Calif., 1996 (ISBN 1-885540-02-7); or, by a coating process, preferably an electrostatic coating process, more preferably by an electromagnetic brush coating process as described in U.S. Pat. No. 6,342,273, issued on Jan. 29, 2002, the disclosure of which is hereby incorporated by reference thereto. For fixing of the toner to the surface of the substrate a contact fusing method like roller fusing may be used, or preferably a non-contact fusing method like an oven, hot air, radiant, flash, solvent, or microwave fusing.
[0028] The process of the present invention and the toner of the present invention will now be more particularly described with reference to some examples which might reveal further inventive features, but to which the present invention is not restricted in its scope.
EXAMPLE 1
[0029] A platelet-shaped brass pigment having a particle size of about 7 μm was initially provided with a silicate coating, followed by an organic coating of stearic acid. This coated pigment was then intensively mixed in various concentrations with a clear toner consisting of polymeric binder, charge control agent, and fumed metal oxide having an average particle size of about 12 μm in a high speed mixer for two minutes to obtain a toner having a brass-coated surface. The concentration of the brass pigments was varied in 2% steps from 2% to 24%.
[0030] Thereafter, these toners were mixed with a carrier, developed, and transferred to paper as usual for commercial printing. Finally, each toner was fixed on the paper surface by contactless fixation in an oven.
[0031] The quality of the gold hue was assessed by image quality experts. The minimum concentration showed a pale gold-like surface, which improved with increasing concentration of pigmentation until approximately a concentration of 14% to 16% had been reached. Surface quality deteriorated again on further increasing the pigment concentration.
EXAMPLE 2
[0032] Example 1 was repeated, except that the toner was fixed with a heated contact fixing apparatus, which comprised a hard roll surface and a Kapton film. Assessment of quality led to the same evaluation as in Example 1 up to about 14% or 16%, but this time the quality remained consistently good at higher pigment concentrations.
EXAMPLE 3
[0033] A toner was prepared by compounding with 17% of brass-pigment from Example 1 by the pigment being compounded with a polymer and a charge control agent in a two-roll mill using low shearing forces, ground, classified, and subjected to a surface treatment with silica to obtain a gold toner having an average particle size of about 8 μm. Printing samples were prepared as in Example 1. Quality testing led to a quality level as in Examples 1 and 2.
EXAMPLE 4
[0034] Example 3 was repeated except that larger shearing forces were used in the mill. The result achieved was the same as in Example 3.
EXAMPLE 5 (Comparative)
[0035] Example 3 was repeated except that the pigment used had been coated with silicate only. The result was poor quality.
EXAMPLE 6 (Comparative)
[0036] Example 4 was repeated except that the pigment used had been coated with silicate only. The result was poor quality.
EXAMPLE 7
[0037] Example 1 was repeated with clear toners having particle sizes of about 12 μm, 8 μm, and 6 μm, which were coated with 20% of pigment from Example 1. The quality level was not quite as high as with 14% to 16% pigment concentration from Example 1. The toner having a particle size of 8 μm exhibited better quality than the toner having 12 μm particle size. The toner having the particle size of 6 μm showed the best quality.
EXAMPLE 8
[0038] Example 7 was repeated using a toner having a sharp melting point, known from U.S. Publication No. 2002/0115010 A1, published on Aug. 22, 2002, for example. Its 120° C. melt viscosity was 12.4 Pa s. The quality level of print samples was again good at a particle size of about 12 μm, better at a particle size of 8 μm, and best at a particle size of 6 μm.
EXAMPLE 9
[0039] Example 8 was repeated except that a yellow toner was used instead of a clear toner. The quality level of the toner having the particle size of about 6 μm was excellent.
EXAMPLE 10
[0040] Example 9 was repeated using a magenta-colored toner. Here too the quality level of the toner having a particle size of about 6 μm was excellent. Changing the viewing angle when observing the printed sample caused the perceived color to vary somewhat between a rich gold tone and a hint of magenta.
EXAMPLE 11
[0041] Example 10 was repeated using a cyan-colored toner. In this case, the quality level of the toner having an average particle size of about 8 μm was excellent. Changing the viewing angle from about perpendicular to a flatter viewing angle when observing the printed sample caused the perceived color to change somewhat between a rich gold tone and a hint of cyan.
EXAMPLE 12 (Comparative)
[0042] A gold-colored print was simulated in toner-based four-color printing. The match was poor. If anything, a dirty yellow was obtained that was devoid of the typical metallic shine.
EXAMPLE 13
[0043] Example 1 was repeated, except that platelet-shaped brass pigment having a particle size of about 7 μm was initially provided with a silicate coating, followed by a 10% by weight organic coating consisting of bis-phenol A based polyester. This coated pigment was then intensively mixed in various concentrations with a clear toner consisting of polymeric binder, charge control agent, and fumed metal oxide having an average particle size of about 12 μm in a high speed mixer for two minutes to obtain a toner having a brass-coated surface. The concentration of the brass pigments was varied in 2% steps from 2% to 24%.
[0044] Thereafter, these toners were mixed with a carrier, developed, and transferred to paper as usual for commercial printing. Finally, each toner was fixed on the paper surface by contact-less fixation in an oven.
[0045] The quality of the gold hue was assessed by image quality experts. The minimum concentration showed a pale gold-like surface, which improved with increasing concentration of pigmentation until approximately a concentration of 14% to 16% had been reached. Surface quality deteriorated again on further increasing the pigment concentration.
EXAMPLE 14
[0046] Example 13 was repeated, except that the toner was fixed with a heated contact fixing apparatus, which comprised a hard roll surface and a Kapton film. Assessment of quality led to the same evaluation as in Example 1 up to about 14% or 16%, but this time the quality remained consistently good at higher pigment concentrations.
EXAMPLE 15
[0047] Example 13 was repeated, except that that platelet-shaped brass pigment having a particle size of about 7 μm was directly provided with an organic coating consisting of bis-phenol A based polyester. The toner was fixed to the paper surface by contact-less fixation in an oven. Assessment of quality led to the same evaluation as in Example 1 up to about 14% or 16%, but this time the quality remained consistently good at higher pigment concentrations.
[0048] The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. | The present invention relates to a toner and process for preparing a toner for reproduction of a metallic, preferably golden or silvery, hue by a printing process, especially for electrophotography. A congeneric process and/or a congeneric toner is preserved with regard to its metallic hue and at the same time not to impair the essential properties of the toner for the printing process in which it is to be used. At least one metallic pigment is provided with a coating of silicate and subsequently with an organic layer and combining the thus obtained particle with toner material. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. Pat. No. 5,715,399 which issued on Feb. 3, 1998 (U.S. application Ser. No. 08/453,273 filed May 30, 1995), which is a continuation-in-part of U.S. Pat. No. 5,727,163 which issued on Mar. 10, 1998 (U.S. application Ser. No. 08/413,242, filed on Mar. 30, 1995).
TECHNICAL FIELD
The present invention relates to a computer method and system for placing an order and, more particularly, to a method and system for ordering items over the Internet.
BACKGROUND OF THE INVENTION
The Internet comprises a vast number of computers and computer networks that are interconnected through communication links. The interconnected computers exchange information using various services, such as electronic mail, Gopher, and the World Wide Web (“WWW”). The WWW service allows a server computer system (i.e., Web server or Web site) to send graphical Web pages of information to a remote client computer system. The remote client computer system can then display the Web pages. Each resource (e.g., computer or Web page) of the WWW is uniquely identifiable by a Uniform Resource Locator (“URL”). To view a specific Web page, a client computer system specifies the URL for that Web page in a request (e.g., a HyperText Transfer Protocol (“HTTP”) request). The request is forwarded to the Web server that supports that Web page. When that Web server receives the request, it sends that Web page to the client computer system. When the client computer system receives that Web page, it typically displays the Web page using a browser. A browser is a special-purpose application program that effects the requesting of Web pages and the displaying of Web pages.
Currently, Web pages are typically defined using HyperText Markup Language (“HTML”). HTML provides a standard set of tags that define how a Web page is to be displayed. When a user indicates to the browser to display a Web page, the browser sends a request to the server computer system to transfer to the client computer system an HTML document that defines the Web page. When the requested HTML document is received by the client computer system, the browser displays the Web page as defined by the HTML document. The HTML document contains various tags that control the displaying of text, graphics, controls, and other features. The HTML document may contain URLs of other Web pages available on that server computer system or other server computer systems.
The World Wide Web is especially conducive to conducting electronic commerce. Many Web servers have been developed through which vendors can advertise and sell product. The products can include items (e.g., music) that are delivered electronically to the purchaser over the Internet and items (e.g., books) that are delivered through conventional distribution channels (e.g., a common carrier). A server computer system may provide an electronic version of a catalog that lists the items that are available. A user, who is a potential purchaser, may browse through the catalog using a browser and select various items that are to be purchased. When the user has completed selecting the items to be purchased, the server computer system then prompts the user for information to complete the ordering of the items. This purchaser-specific order information may include the purchaser's name, the purchaser's credit card number, and a shipping address for the order. The server computer system then typically confirms the order by sending a confirming Web page to the client computer system and schedules shipment of the items.
Since the purchaser-specific order information contains sensitive information (e.g., a credit card number), both vendors and purchasers want to ensure the security of such information. Security is a concern because information transmitted over the Internet may pass through various intermediate computer systems on its way to its final destination. The information could be intercepted by an unscrupulous person at an intermediate system. To help ensure the security of the sensitive information, various encryption techniques are used when transmitting such information between a client computer system and a server computer system. Even though such encrypted information can be intercepted, because the information is encrypted, it is generally useless to the interceptor. Nevertheless, there is always a possibility that such sensitive information may be successfully decrypted by the interceptor. Therefore, it would be desirable to minimize the sensitive information transmitted when placing an order.
The selection of the various items from the electronic catalogs is generally based on the “shopping cart” model. When the purchaser selects an item from the electronic catalog, the server computer system metaphorically adds that item to a shopping cart. When the purchaser is done selecting items, then all the items in the shopping cart are “checked out” (i.e., ordered) when the purchaser provides billing and shipment information. In some models, when a purchaser selects any one item, then that item is “checked out” by automatically prompting the user for the billing and shipment information. Although the shopping cart model is very flexible and intuitive, it has a downside in that it requires many interactions by the purchaser. For example, the purchaser selects the various items from the electronic catalog, and then indicates that the selection is complete. The purchaser is then presented with an order Web page that prompts the purchaser for the purchaser-specific order information to complete the order. That Web page may be prefilled with information that was provided by the purchaser when placing another order. The information is then validated by the server computer system, and the order is completed. Such an ordering model can be problematic for a couple of reasons. If a purchaser is ordering only one item, then the overhead of confirming the various steps of the ordering process and waiting for, viewing, and updating the purchaser-specific order information can be much more than the overhead of selecting the item itself. This overhead makes the purchase of a single item cumbersome. Also, with such an ordering model, each time an order is placed sensitive information is transmitted over the Internet. Each time the sensitive information is transmitted over the Internet, it is susceptible to being intercepted and decrypted.
SUMMARY OF THE INVENTION
An embodiment of the present invention provides a method and system for ordering an item from a client system. The client system is provided with an identifier that identifies a customer. The client system displays information that identifies the item and displays an indication of an action (e.g., a single action such as clicking a mouse button) that a purchaser is to perform to order the identified item. In response to the indicated action being performed, the client system sends to a server system the provided identifier and a request to order the identified item. The server system uses the identifier to identify additional information needed to generate an order for the item and then generates the order.
The server system receives and stores the additional information for customers using various computer systems so that the server system can generate such orders. The server system stores the received additional information in association with an identifier of the customer and provides the identifier to the client system. When requested by the client system, the server system provides information describing the item to the requesting client system. When the server system receives a request from a client system, the server system combines the additional information stored in association with the identifier included in the request to effect the ordering of the item.
An embodiment of the present invention also provides a hierarchical technique for displaying information in a form. Also, an embodiment provides an editing mode in which the contents of a form are displayed and when selected an editing window is presented so that the contents of the field can be edited. After editing, a form is displayed with the edited contents of the field.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1C illustrate single-action ordering in one embodiment of the present invention.
FIG. 2 is a block diagram illustrating an embodiment of the present invention.
FIG. 3 is a flow diagram of a routine that enables single-action ordering for a customer.
FIG. 4 is a flow diagram of a routine to generate a Web page in which single-action ordering is enabled.
FIG. 5 is a flow diagram of a routine which processes a single-action order.
FIG. 6 is a flow diagram of a routine for generating a single-action order summary Web page.
FIG. 7 is a flow diagram of a routine that implements an expedited order selection algorithm.
FIGS. 8A-8C illustrate a hierarchical data entry mechanism in one embodiment.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a method and system for single-action ordering of items in a client/server environment. The single-action ordering system of the present invention reduces the number of purchaser interactions needed to place an order and reduces the amount of sensitive information that is transmitted between a client system and a server system. In one embodiment, the server system assigns a unique client identifier to each client system. The server system also stores purchaser-specific order information for various potential purchasers. The purchaser-specific order information may have been collected from a previous order placed by the purchaser. The server system maps each client identifier to a purchaser that may use that client system to place an order. The server system may map the client identifiers to the purchaser who last placed an order using that client system. When a purchaser wants to place an order, the purchaser uses a client system to send the request for information describing the item to be ordered along with its client identifier. The server system determines whether the client identifier for that client system is mapped to a purchaser. If so mapped, the server system determines whether single-action ordering is enabled for that purchaser at that client system. If enabled, the server system sends the requested information (e.g., via a Web page) to the client computer system along with an indication of the single action to perform to place the order for the item. When single-action ordering is enabled, the purchaser need only perform a single action (e.g., click a mouse button) to order the item. When the purchaser performs that single action, the client system notifies the server system. The server system then completes the order by adding the purchaser-specific order information for the purchaser that is mapped to that client identifier to the item order information (e.g., product identifier and quantity). Thus, once the description of an item is displayed, the purchaser need only take a single action to place the order to purchase that item. Also, since the client identifier identifies purchaser-specific order information already stored at the server system, there is no need for such sensitive information to be transmitted via the Internet or other communications medium.
FIGS. 1A-1C illustrate single-action ordering in one embodiment of the present invention. FIG. 1A illustrates the display of a Web page describing an item that may be ordered. This example Web page was sent from the server system to the client system when the purchaser requested to review detailed information about the item. This example Web page contains a summary description section 101 , a shopping cart section 102 , a single-action ordering section 103 , and a detailed description section 104 . One skilled in the art would appreciate that these various sections can be omitted or rearranged or adapted in various ways. In general, the purchaser need only be aware of the item or items to be ordered by the single action and of the single action needed to place the order. The summary description and the detailed description sections provide information that identifies and describes the item(s) that may be ordered. The shopping cart section provides the conventional capability to add the described item to a shopping cart. The server system adds the summary description, the detailed description, and the shopping cart sections to each Web page for an item that may be ordered. The server system, however, only adds the single-action ordering section when single-action ordering is enabled for that purchaser at that client system. (One skilled in the art would appreciate that a single Web page on the server system may contain all these sections but the single-action ordering section can be selectively included or excluded before sending the Web page to the client system.) This example single-action ordering section allows the purchaser to specify with a single click of a mouse button to order the described item. Once the purchaser clicks the mouse button, the item is ordered, unless the purchaser then takes some action to modify the order. The single-action ordering section contains a single-action ordering button 103 a, purchaser identification subsection 103 b, and single-action ordering information subsections 103 c and 103 d. The purchaser information subsection displays enough information so that the purchaser can verify that the server system correctly recognizes the purchaser. To reduce the chances of sensitive information being intercepted, the server system sends only enough information so that the purchaser is confident that the server system correctly identified the purchaser but yet not enough information to be useful to an unscrupulous interceptor. The additional information subsections allow the purchaser to obtain various settings or obtain more information related to the single-action ordering. If the purchaser wants to verify the shipping address, the purchaser can select the “check shipping address” label. In response to this selection, the server system may require the purchaser to perform a “login” so that the identity of the purchaser can be verified before the shipping information is viewed or modified. The server system then sends a Web page to the client system for display and possible modification of the shipping address. In this way, the transmitting of the sensitive shipping address can be avoided unless requested by the verified purchaser.
When the purchaser selects the single-action ordering button, the client system sends a message to the server system requesting that the displayed item be ordered. After the server system processes the message, the server system provides to the client system a new Web page that confirms receipt of the single-action order. FIG. 1B illustrates the display of a Web page confirming a single-action order. The confirming Web page contains essentially the same information as the Web page describing the item (i.e., FIG. 1A) except that an order confirmation section 105 is displayed at the top of the Web page. The order confirmation section confirms that the order has been placed and provides an opportunity for the purchaser to review and change the single-action order. Alternatively, the confirming Web page can be identical to the Web page describing the item (i.e., FIG. 1 A), except that the single-action ordering button is replaced with a message confirming the order.
If a single-action ordering is not currently enabled for the client system but could be enabled,. then the server system can generate a Web page like FIG. 1A, except that the single-action ordering button 103 a is replaced by a single-action ordering enable button. Such a replacement button could contain text instructing the purchaser to click on the button to enable single-action ordering. When the purchaser clicks on that button, the server system would send the Web page of FIG. 1A to be displayed. Single-action ordering can be enabled whenever the server system has stored sufficient purchaser-specific order information for that client system to complete a single-action order. If the server system does not have sufficient information, then when the purchaser selects the single-action ordering button, the server system can provide a Web page to collect the additional information that is needed. The server system may require the purchases to “login” so that the identity of the purchaser can be verified before the single-action ordering is enabled.
To help minimize shipping costs and purchaser confusion, the server system may combine various single-action orders into a multiple-item order. For example, if a purchaser orders one item using the single-action ordering and five minutes later orders another item using the single-action ordering, then those orders may be cost effectively combined into a single order for shipping. The server system combines the single-action orders when their expected ship dates are similar. For example, if one item is immediately available and the other item will be available in one day, then the two single-action orders may be cost-effectively combined. However, if the other item will not be available for two weeks, then the two single-item orders would not be combined. FIG. 1C illustrates the display of a Web page representing four single-action orders that have been combined into two separate multiple-item orders based on the availability of the items. The order information 106 indicates that item 1 and item 2, which will be available in three or fewer days, have been combined into one order. The order information 107 indicates that items 3 and 4, which will not be available within one week, are combined into a separate order. In one embodiment, the server system may combine single-action orders that are placed within a certain time period (e.g., 90 minutes). Also, the server system may combine or divide orders when the orders are scheduled for shipment based on the then current availability of the items ordered. This delayed modification of the orders is referred to as “expedited order selection” and is described below in detail.
FIG. 2 is a block diagram illustrating an embodiment of the present invention. This embodiment supports the single-action ordering over the Internet using the World Wide Web. The server system 210 includes a server engine 211 , a client identifier/customer table 212 , various Web pages 213 , a customer database 214 , an order database 215 , and an inventory database 216 . The server engine receives HTTP requests to access Web pages identified by URLs and provides the Web pages to the various client systems. Such an HTTP request may indicate that the purchaser has performed the single action to effect single-action ordering. The customer database contains customer information for various purchasers or potential purchasers. The customer information includes purchaser-specific order information such as the name of the customer, billing information, and shipping information. The order database 215 contains an entry for each order that has not yet been shipped to a purchaser. The inventory database 216 contains a description of the various items that may be ordered. The client identifier/customer table 212 contains a mapping from each client identifier, which is a globally unique identifier that uniquely identifies a client system, to the customer last associated with that client system. The client system 220 contains a browser and its assigned client identifier. The client identifier is stored in a file, referred to as a “cookie.” In one embodiment, the server system assigns and sends the client identifier to the client system once when the client system first interacts with the server system. From then on, the client system includes its client identifier with all messages sent to the server system so that the server system can identify the source of the message. The server and client systems interact by exchanging information via communications link 230 , which may include transmission over the Internet.
One skilled in the art would appreciate that the single-action ordering techniques can be used in various environments other than the Internet. For example, single-action ordering can also be in an electronic mail environment in which an item is described in an electronic mail message along with an indication of the single action that is to be performed to effect the ordering of the item. Also, various communication channels may be used such as local area network, wide area network, or point-to-point dial up connection. Also, a server system may comprise any combination of hardware or software that can generate orders in response to the single action being performed. A client system may comprise any combination of hardware or software that can interact with the server system. These systems may include television-based systems or various other consumer products through which orders may be placed.
FIG. 3 is a flow diagram of a routine that enables single-action ordering for a customer. To enable single-action ordering, a server system needs to have information about the customer that is equivalent to the purchaser-specific order information. The server system can obtain this information in various ways. First, the server system could ask the customer if they would like to have single-action ordering enabled. If so, then the server system could prompt the customer using a Web page for the purchaser-specific order information. Second, the server system could also save the purchaser-specific order information collected when an order is placed conventionally. The server system could, either automatically or with the customer's assent, enable single-action ordering. In step 301 , the server system retrieves the client identifier that was sent by the client system. In step 302 , the server system updates the client identifier/customer table to indicate that the generated client identifier has been associated with that customer. In step 303 , the server system sets a flag indicating that single-action ordering is enabled for that client identifier and that customer combination. That flag may be stored in the client identifier/customer table. In step 304 , the server system supplies a confirming Web page to the client system. The next time a purchaser attempts to order an item, the client system will supply its client identifier to the server system. If single-action ordering is enabled for that purchaser, the server system will assume that the purchaser is the customer associated with that client identifier in the client identifier/customer table. Thus, a purchaser may not want to allow the server system to enable single-action ordering if there is a possibility that someone else may use that same client system.
FIG. 4 is a flow diagram of a routine to generate a Web page in which single-action ordering is enabled. When single-action ordering is enabled, the server system generates a Web page describing an item as is conventionally done and then adds a single-action ordering section. In one embodiment, the server system adds partial purchaser-specific order information to the section. This information may include the customer's name, a shipping address moniker selected by the purchaser (e.g., “at home”), and the last five digits of a credit card number or a nickname selected by the purchaser. Such partial information should be the minimum information sufficient to indicate to the purchaser whether or not the server system is using the correct purchaser-specific order information. In step 401 , the server system generates a standard shopping cart-type Web page for the item. In step 402 , if the single-action ordering flag has been set for the client identifier and customer combination, then the server system continues at step 403 , else the server system completes. In step 403 , the server system adds the single-action section to the Web page and completes.
FIG. 5 is a flow diagram of a routine which processes a single-action order. When a purchaser performs the single action needed to place an order, the client system notifies the server system. The server system then combines the purchaser-specific order information for the customer associated with the client system with the item order information to complete the order. The single-action order may also be combined with other single-action orders and possibly with other conventionally placed orders to reduce shipping costs. In one embodiment, single-action orders can be combined if they are placed within a certain time period of each other (e.g., 90 minutes). This routine illustrates the combining of the single-action orders into a short-term order (e.g., available to be shipped in less than a week) and a long-term order (e.g., available to be shipped in more than a week). One skilled in the art would appreciate that the single-action orders can be combined in various ways based on other factors, such as size of shipment and intermediate-term availability. In step 501 , if the item is expected to be shipped in the short term, then the server system continues at step 502 , else the server system continues at step 505 . In step 502 , if a short-term order has already been opened for the purchaser, then the server system continues at step 504 , else the server system continues at step 503 . In step 503 , the server system creates a short-term order for the purchaser. In step 504 , the server system adds the item to the short-term order and continues at step 508 . In step 505 , if a long-term order has already been opened for the purchaser, then the server system continues at step 507 , else the server system continues at step 506 . In step 506 , the server system creates a long-term order for the purchaser. In step 507 , the server system adds the item to the long-term order. In step 508 , the server system generates and sends the confirmation and completes.
FIG. 6 is a flow diagram of a routine for generating a single-action order summary Web page. This Web page (e.g., FIG. 1C) gives the user the opportunity to view and modify the short-term and long-term single-action orders. In step 601 , the server system adds the standard single-action order information to the Web page. In step 602 , if a short-term order is open, then the server system adds the short-term order to the Web page in step 603 . In step 604 , if a long-term order is open, then the server system adds the long-term order information to the Web page in step 605 and completes.
FIG. 7 is a flow diagram of a routine that implements an expedited order selection algorithm. The goal of the expedited order selection algorithm is to minimize the number of orders sent to each destination so that shipping costs are reduced. A destination may be a specific shipping address plus a specific purchaser's billing details. Orders that are sent to the same destination are known as “sibling orders.” The algorithm has two stages. In the first stage, the algorithm schedules for shipment the orders for destinations for which all the sibling orders are filled. An order is filled when all its items are currently in inventory (i.e., available) and can be shipped. For each group of sibling orders, the algorithm combines those sibling orders into a single combined order so that only one order is currently scheduled for shipment to each destination. In the second stage, the algorithm combines and schedules groups of sibling orders for which some of the sibling orders are not filled or partially filled. The algorithm may split each partially filled sibling order into a filled sibling order and a completely unfilled sibling order. The algorithm then combines all the filled sibling orders into a single combined order and schedules the combined order for shipment. If any group has only one sibling order and that order is partially filled, then the algorithm in one embodiment does not split that order to avoid making an extra shipment to that destination.
During the second stage, the algorithm may select and schedule groups of sibling orders in a sequence that is based on the next fulfillment time for an item in the group. The next fulfillment time for a group of sibling orders is the minimum expected fulfillment time of the items in that group of sibling orders. For example, if a group of sibling orders has seven items that are not yet fulfilled and their expected fulfillment times range from 3 days to 14 days, then the next fulfillment time for that group is 3 days. The algorithm first schedules those groups of sibling orders with the largest next fulfillment time. For example, if 6 groups have next fulfillment times of 3, 5, 7, 10, 11, and 14 days, respectively, then the algorithm first selects and schedules the sibling orders in the group with the next fulfillment time of 14 days, followed by the group with the next fulfillment time of 11 days, and so on. By delaying the scheduling of groups with short next fulfillment times, the algorithm increases the chances of additional items becoming available (because of the shortness of the next fulfillment time) and thus combined with the scheduled order.
Steps 701 - 703 represent the first stage of the expedited order selection algorithm, and steps 704 - 706 represent the second stage of the expedited selection order algorithm. In steps 701 - 703 , the algorithm loops selecting groups in which all sibling orders are filled and combining the orders. In step 701 , the algorithm selects the next group with all sibling orders that are filled. In step 703 , if all such groups have already been selected, then the algorithm continues with the second stage in step 704 , else the algorithm continues at step 703 . In step 703 , the algorithm combines and schedules the orders in the selected group and loops to step 701 . In step 704 , the algorithm selects the next group of sibling orders that has the largest next fulfillment time. In step 705 , if all such groups have already been selected, then the algorithm is done, else the algorithm continues at step 706 . In step 706 , the algorithm combines and schedules the orders in the selected group and loops to step 704 . When the expedited order selection algorithm is being performed, new orders and new inventory may be received. Whenever such new orders and new inventory is received, then the algorithm restarts to schedule and combine the new orders as appropriate.
Although the algorithm has been described as having two stages, it could be implemented in an incremental fashion where the assessment of the first and second stages are redone after each order is scheduled. One skilled in the art would recognize that there are other possible combinations of these stages which still express the same essential algorithm.
FIGS. 8A-8C illustrate a hierarchical data entry mechanism in one embodiment. When collecting information from a user, a Web page typically consists of a long series of data entry fields that may not all fit onto the display at the same time. Thus, a user needs to scroll through the Web page to enter the information. When the data entry fields do not fit onto the display at the same time, it is difficult for the user to get an overall understanding of the type and organization of the data to be entered. The hierarchical data entry mechanism allows a user to understand the overall organization of the data to be entered even though the all data entry fields would not fit onto the display at the same time. FIG. 8A illustrates an outline format of a sample form to be filled in. The sample form contains various sections identified by letters A, B, C, and D. When the user selects the start button, then section A expands to include the data entry fields for the customer name and address. FIG. 8B illustrates the expansion of section A. Since only section A has been expanded, the user can view the data entry fields of section A and summary information of the other sections at the same time. The user then enters data in the various data entry fields that are displayed. Upon completion, the user selects either the next or previous buttons. The next button causes section A to be collapsed and section B to be expanded so that financial information may be entered. FIG. 8C illustrates the expansion of section B. If the previous button is selected, then section A would collapse and be displayed as shown in FIG. 8 A. This collapsing and expanding is repeated for each section. At any time during the data entry, if an error is detected, then a Web page is generated with the error message in close proximity (e.g., on the line below) to the data entry field that contains the error. This Web page is then displayed by the client system to inform the user of the error. In addition, each of the data “entry” fields may not be editable until the user clicks on the data entry field or selects an edit button associated with the data entry field. In this way, the user is prevented from inadvertently changing the contents of an edit field. When the user clicks on a data entry field, a new Web page is presented to the user that allows for the editing of the data associated with the field. When editing is complete, the edited data is displayed in the data “entry” field. Because the fields of the form are thus not directly editable, neither “named-submit” buttons nor Java are needed. Also, the form is more compact because the various data entry options (e.g., radio button) are displayed only on the new Web page when the field is to be edited.
Although the present invention has been described in terms of various embodiments, it is not intended that the invention be limited to these embodiments. Modification within the spirit of the invention will be apparent to those skilled in the art. For example, the server system can map a client identifier to multiple customers who have recently used the client system. The server system can then allow the user to identify themselves by selecting one of the mappings based preferably on a display of partial purchaser-specific order information. Also, various different single actions can be used to effect the placement of an order. For example, a voice command may be spoken by the purchaser, a key may be depressed by the purchaser, a button on a television remote control device may be depressed by the purchaser, or selection using any pointing device may be effected by the purchaser. Although a single action may be preceded by multiple physical movements of the purchaser (e.g., moving a mouse so that a mouse pointer is over a button), the single action generally refers to a single event received by a client system that indicates to place the order. Finally, the purchaser can be alternately identified by a unique customer identifier that is provided by the customer when the customer initiates access to the server system and sent to the server system with each message. This customer identifier could be also stored persistently on the client system so that the purchaser does not need to re-enter their customer identifier each time access is initiated. The scope of the present invention is defined by the claims that follow. | A method and system for placing an order to purchase an item via the Internet. The order is placed by a purchaser at a client system and received by a server system. The server system receives purchaser information including identification of the purchaser, payment information, and shipment information from the client system. The server system then assigns a client identifier to the client system and associates the assigned client identifier with the received purchaser information. The server system sends to the client system the assigned client identifier and an HTML document identifying the item and including an order button. The client system receives and stores the assigned client identifier and receives and displays the HTML document. In response to the selection of the -order button, the client system sends to the server system a request to purchase the identified item. The server system receives the request and combines the purchaser information associated with the client identifier of the client system to generate an order to purchase the item in accordance with the billing and shipment information whereby the purchaser effects the ordering of the product by selection of the order button. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This patent application concerns a signalling device, and, more specifically, a device for keeping birds away with differential management functions.
2. Description of the Related Art
Birds represent a serious problem in a variety of environments. For example, in agriculture, birds damage plants and cultivations, in fish-growing farms, birds attack the fish stock, and in airports and other surfaces to be used by airplanes, birds hinder the movement of the airplanes, especially during take-off and landing.
A device for keeping birds away is known and adopted in the prior art, and generally consists of a casing containing a pulse sound and/or light emitter.
Said device in the prior art emits sounds and/or light flashes at regular intervals and is usually positioned in the area that must be protected against birds. Such light and sound emitter operates at regular intervals that are predetermined during the production phase.
This device is not very effective, because birds memorize the time intervals between successive sound or light signals, entering the area protected by one of these devices after a signal and leaving it just before the successive one. Even if the related time interval is changed, after a while the birds memorize the new sequence, thus making the new adjustment useless.
Some devices are adjusted or manufactured to emit sound and/or light signals continuously. These devices are not very effective either, because the birds, after a lapse of time during which they get used to these signals, become insensitive to sound and light emissions.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention is to keep birds away by means of one or more devices, positioned in the area to be protected according to a modular and integrated network, wherein light and sound signals are generated with different frequencies, amplitudes, modulations, and rhythms, and wherein the emissions at each point are determined by a control unit.
It is another objective of the present invention to keep birds away by emitting sound and light signals from different sources according to predefined, random or pseudo-random sequences.
A new device for keeping birds away with differential management functions is provided, comprising a control unit connected to a pilot system that controls and pilots one or more emission units.
Each emission unit comprises a casing that may be provided with a servo controlled, opening protection cover. Inside the casing there are a control unit, one or more light emitters and one or more sound emitters.
The control unit controls the opening of the protection cover, if provided, and the sound and light emitters. Further, the control unit receives operating instructions from the pilot system, controls the correct operation of all the components of the emission unit and sends malfunction reports to the pilot system, when necessary.
The pilot system also comprises a casing that includes an opening cover, a control circuit, one or more light emitters and one or more sound emitters. The control circuit of the pilot system, besides controlling any sound and light emitters connected to it, is provided with a device for radio or wire communication with the control unit, receiving from the control unit an operating configuration for all the emission units and transmitting the appropriate commands to each emission unit, and receiving also from each emission unit the relevant function or malfunction report and transmitting that report to the control unit.
The control unit preferably comprises a computer with a radio or wire communication system, and makes it possible to monitor the correct operation of all the pilot and emission units continuously, to set the desired operating modes for each emission unit, to determine and vary the sequences and combinations of sound and light signals for groups of emission units or for each single emission unit, and also to develop the operating schedule of the whole system.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 a is a perspective view of an emission unit with an opening cover.
FIG. 1 b is a perspective view of an emission unit without an opening cover.
FIG. 2 is a schematic representation of an amplification unit.
FIG. 3 is a schematic representation of part of a control circuit for noise generation.
FIG. 4 is a schematic representation of the connection of control units, pilot systems, and emission units.
DETAILED DESCRIPTION OF THE INVENTION
A detailed descriptions of an embodiment of the invention is provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, the specific details disclosed herein are not to be interpreted as limiting, but rather as a representative basis for teaching one skilled in the art how to employ the present invention in virtually any detailed system, structure, or manner.
Turning first to FIGS. 1 a and 1 b, an emission unit comprises a casing (E 1 ) that may have a cover (E 2 ), a control unit (E 3 ), one or more light emitters (E 4 ) and one or more sound emitters (E 5 ).
The casing (E 1 ) and the relevant cover (E 2 ) contain the control unit (E 3 ), as well as the sound emitters (E 5 ) and light emitters (E 4 ), protecting these components from the weather. In particular, the cover (E 2 ) of the casing (E 1 ) is totally or partially connected to a lifting mechanism (E 22 ) that provides for the opening or closing of the cover, depending on whether the emission unit is to be protected or not from the weather.
Light emitters (E 4 ) and sound emitters (E 5 ) are preferably housed inside the cover (E 2 ). When the cover (E 2 ) is completely open, the light emitters (E 4 ) and sound emitters (E 5 ) are directed in an upward direction. Instead, when the cover (E 2 ) is in an only partially open position, to protect the inside from the weather, the light emitters (E 4 ) and sound emitters (E 5 ) are directed towards a preferably reflecting surface that also protects the control unit (E 3 ). Inside the casing (E 1 ) there are the control unit (E 3 ) and the amplification unit, whose connections and operation are diagrammatically represented in FIG. 2 .
The light emitters (E 4 ) are preferably constituted by one or more stroboscopic lights or similar lights inserted in the cover (E 2 ). The sound emitters (E 5 ) are preferably constituted by a set of loudspeakers or acoustic diffusers with high efficiency and high pass-band connected to a power amplifier. Said sound emitters (E 5 ) are preferably inserted in the cover (E 2 ).
The control unit (E 3 ) comprises a logic circuit for management, self-diagnosis and communication with a pilot system (P), as well as a noise generator.
The part of the logic circuit in control unit (E 3 ) relevant to management, self-diagnosis and communication provides for monitoring the correct operation of the entire emission unit, for transmitting the correct operation or malfunction report to the pilot system (P), for setting and operating the noise generator, for operating the light emitters (E 4 ) and sound emitters (E 5 ) and the cover (E 2 ) lifting mechanism (E 22 ).
The part of the control unit (E 3 ) related to the noise generator, diagrammatically represented in FIG. 3 , substantially comprises a first device (E 31 ) for generating variously modulated wave forms, which can be emitted in predefined manner, such as at random or in a predetermined manner, for example through a complex algorithm, and a second device (E 32 ) for generating predetermined sounds, for example blasts, explosions, howls, or bursts. Said two modules (E 31 , E 32 ), are capable of producing signals with different types of modulation in a wide spectrum of audible and ultrasonic frequencies with emission level variations, both at random and piloted.
The first and second devices (E 31 , E 32 ) can be used separately or together, by means of an apposite adder (AD 2 ) and the relevant switches (SW 4 , SW 5 ), for the production of more or less complex noise effects. The related signals are sent to a suitable power amplifier that is in turn connected to the sound emitters (E 5 ).
The wave form generator (E 31 ) comprises a frequency modulator (FM) followed by an adder (AD 1 ) and by an amplitude modulator (AM). The three stages are powered by as many generators of modulating frequencies (MG 1 , MG 2 and MG 3 ) and by a carrier frequency generator (CG). The frequency and amplitude of each generator (MG 1 , MG 2 and MG 3 ) are variable within predefined limits and are piloted at random or in a predetermined manner, depending on the desired sound effect. It is possible to exclude one or more generators (MG 1 , MG 2 and MG 3 ) by means of apposite switches (SW 1 , SW 2 , SW 3 ), in order to obtain different signal combinations.
The carrier (CG) and modulating frequency (MG 1 , MG 2 , MG 3 ) generators are all of the frequency synthesis type and both their frequency and amplitude can be modified through the control unit (E 3 ).
The above described emission unit is connected to the pilot system (P). The pilot system (P) is built in similar fashion to an emission unit and comprises a casing with or without an opening cover, a control circuit, an amplification unit, one or more light emitters and one or more sound emitters. Besides, pilot system (P) is provided with suitable interfaces for connection to the various emission units and with a radio connection module for connection to a control unit (C).
The various control units (C), pilot systems (P) and emission units (E) are connected to one another as diagrammatically shown in FIG. 4 to protect an area (L), for example the strip of an airport.
The pilot system (P) substantially receives from the control unit (C) the operating configuration of all the emission units (in FIG. 4 , emission units Ea–Ef), sends the relevant commands to each emission unit (Ea–Ef), and also receives from each emission unit (Ea–Ef) the relevant correct operation or malfunction report transmitting it to the control unit (C).
The control unit (C) preferably comprises a computer, with wire or radio communication system for connection to the pilot system (P), together with dedicated software.
The control unit (C) makes it possible to constantly monitor the correct operation of all the pilot systems (P) and emission units, to set the operating mode for each emission unit through a program capable of activating the light emitters (E 4 ) and sound emitters (E 5 ), as well as of defining the sequences and combinations of sound and light signals for groups of emission units or for single emission units, whether in a predetermined, pseudo-random, or random manner.
The operation of the new device for keeping birds away with differential management functions requires that both the emission units (Ea–Ef) and each pilot system (P) have the possibility to operate individually or to be coordinated. In both cases management is carried out by the pilot system (P), duly piloted by the control unit (C). In each case the time schedule and the characteristics of the sound and light signals will be determined by the pilot system (P) in combination, wherein the combination is predetermined, pseudo-random, or random. For example, it will be possible to obtain the emission of independent random signals from each emission unit, wherein each unit will emit a different random signal, or of random signals depending on the pilot system (P), wherein all emission units will emit the same random signal.
The emission units can emit different or identical sounds in different sequences (linear sequence, alternate sequence, chessboard sequence, etc.). For example, in the case of six emission units (Ea–Ef), some of the possible sequences may be the following:
Ea, Ed, Eb, Ee, Ec, Ef; Ea Ee Ec together, Ed Eb Ef together; Ea, Eb, Ec, Ef, Ee, Ed; Ea Eb Ec together, Ed Ee Ef together; Ea, Eb, Ec, Ed, Ee, Ef; Ea Eb Ec Ed Ee Ef together; Ea Ed together, Eb Ee together, Ec Ef together.
The beginning, the duration, and the sound characteristics of each stage of a sequence can be varied by the pilot system (P) in a random, pseudo-random or predetermined manner.
Even when the operation of the emission units is completely independent and randomized, it is possible to still set some parameters, such as a combination of parameters, for example the range of carrier and modulating frequencies emitted, the maximum and minimum duration of each stage, or the minimum and maximum amplitude of each signal.
It is also possible to provide for the operation of sub-groups of emission units (Ea–Ef) according to specific areas to be covered: for example Ec and Ef may operate independently and at random, while Ea, Eb, Ed and Ee may be activated in a piloted manner.
The new device for keeping birds away with differential management functions offers considerable advantages over the prior art.
There are no fixed time and/or frequency intervals between the emission of sound and/or light signals, and therefore the birds cannot know in advance when a given signal is going to start and/or to end.
There are no continuous acoustic signals and/or flashes that allow the birds to become accustomed to these types of signals.
Operating times, emitted frequencies, and synchronization, succession or independence among the various units makes the sound and/or light emissions of the set of emission units completely unpredictable, which prevents the birds from memorizing the operating times and sequences of the various emission units.
The operation of each emission unit in the self-diagnosis mode and the consequent report on its operating condition to the control unit (C) through the pilot system (P) make it possible to constantly verify the correct operation of all the emission units, thus allowing also the necessary maintenance operations and repairs to be carried out on the emission units that may be functioning incorrectly and on the specific malfunctioning devices.
While the invention has been described in connection with the above described embodiment, it is not intended to limit the scope of the invention to the particular forms set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the scope of the invention. | A device for keeping birds away with differential management functions, comprising a control unit connected to a pilot system that controls one or more emission units. The pilot system and each emission unit comprise a casing with an optional protection cover and lifting mechanism; a control circuit; and one or more light and sound emitters. The control unit controls the light and sound emitters, receives operating instructions from the pilot system, and verifies the correct operation of all components of the unit. The control unit preferably comprises a computer with radio or wire communication capability, constantly monitors the correct operation of all pilot and emission units, sets the operating mode for each emission unit, determines and varies the sequences and combinations of the sound and light signals emitted by groups of emission units or by individual emission units, and develops the operating schedule for the entire system. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a self-propelled building machine, in particular a road cutting machine or a surface miner, having a machine frame and a chassis that comprises running gear that rests on the ground below. Furthermore, the present invention relates to a method for operating such a building machine.
[0003] 2. Description of the Prior Art
[0004] Self-propelled building machines of the above type comprise a working device that is arranged on the machine frame, which comprises a working roller that has to be brought into contact with the ground to work the ground below. This working roller can be in the form of a milling or a cutting roller, by means of which, for example, damaged layers of road can be removed, or mineral resources can be extracted from the ground.
[0005] In known road cutting machines and surface miners, the working roller is located in a roller housing which is open at the bottom, that is closed by a pressure element arranged in the direction of working in front of the working roller and by a stripper device arranged in the direction of working behind the roller. On at least one side, the roller housing is closed by a plate extending in the direction of working, which is designated as an edge protection.
[0006] The height of the machine frame of the known building machines can be adjusted in relation to the surface of the ground if the machine is positioned with the running gear resting on the ground. For this purpose, such building machines comprise a device for adjusting the height of the machine frame, which is activated by a control unit. As the working device is arranged on the machine frame, this adjustment affects not only the height of the machine frame, but also that of the working roller. In addition, the height of the working device can be adjusted in relation to the machine frame.
[0007] During the operation of the building machine, the height of the machine frame is set in such a way that the cutting roller of the working device penetrates the ground. At the same time, if necessary, the height of the pressure element and the stripper device and also of the edge protection can be adjusted in relation to the machine frame. In general, the pressure element, the stripper device and the edge protection are mounted in a floating manner, so that the height can be adjusted independently. This has the effect that the pressure element, the stripper device and the edge protection can follow the surface of the ground and the roller housing is always closed at the bottom.
[0008] When adjusting the working depth of the working device, the problem arises that, when the machine frame is lowered, the working roller does not penetrate the ground quickly enough. The speed at which the working roller penetrates the ground is determined by the condition of the working roller, the condition of the ground and the weight of the building machine. If the working roller does not penetrate the ground quickly enough and the machine frame is lowered further, there is a risk that the working roller will sink too deep into the ground. This problem is known in practice as a “sighting hole”.
[0009] It can also happen during the operation of the building machine that the edge protection, the stripper device or the pressure element, which are height-adjustably suspended or mounted on the machine frame, can become jammed while being adjusted. If the machine frame is lowered with the edge protection, the stripper device or the pressure element in a jammed state, it can happen that the building machine jerks backwards onto the running gears or the working roller if the jamming is suddenly released. This can damage the working roller or the drive train, for example.
SUMMARY OF THE INVENTION
[0010] It is therefore the aim of the present invention to propose a self-propelled building machine in which an uncontrolled lowering of the machine is prevented when the working depth of the working device is adjusted. A further aim of the present invention is to propose a method for operating a building machine whereby an uncontrolled lowering of the machine is avoided.
[0011] According to the present invention, this aim is achieved by the features contained in the independent claims of the patent. The objects of the dependent claims relate to preferred embodiments of the invention.
[0012] The building machine according to the present invention provides for an operating mode to adjust the working depth of the working device, in which the machine frame is lowered. This operating mode is characterised by the fact that although the working device is driven, the machine is at a standstill. In this respect, this operating mode differs from the operating mode in which the working device is driven so that the ground can be worked during the forward movement of the machine.
[0013] The basic principle of the present invention lies in the fact that, in order to prevent any uncontrolled sinking of the building machine in the above operating mode, the imposed weight exercised by the building machine on the running gears has to be measured, whereby it is assumed that the uncontrolled sinking of the building machine occurs if the running gears are not resting on the ground when the cutting roller is lowered.
[0014] The machine frame of the building machine is lowered as a result of the relative movement of the running gears and the machine frame. If the machine frame is to be lowered at a faster rate than that at which the working roller penetrates the ground, the running gears are lifted off the ground, so that the imposed weight is less than a predetermined threshold weight measured against the imposed weight of the building machine and the running gears on the ground. In practice, the imposed weight falls to zero at the moment at which the running gears are lifted off the ground and all control over the lowering process is immediately lost.
[0015] In the building machine according to the present invention and the method according to the present invention, the lifting of the running gears is identified by measuring the imposed weight, whereby depending on the imposed weight, the lowering action will be either controlled or uncontrolled. If the lowering action is uncontrolled, appropriate steps must be taken.
[0016] In principle, the imposed weight can only be measured on one of the running gears, on a part of the running gears or on all height-adjustable running gears. Preferably, the imposed weight is measured on all height-adjustable running gears, whereby preferably an uncontrolled lowering can be determined in relation to the imposed weight if at least one of the running gears is lifted off the ground.
[0017] For the purpose of the present invention, the term “running gear” is understood to signify any means by which the building machine rests as intended on the ground. The running gears can be, for example, wheels or crawler tracks.
[0018] The building machine according to the present invention is characterised by a measuring device, which comprises a means for measuring the imposed weight applied by the building machine on at least one of the running gears or alternatively a physical value correlating to the imposed weight. In practice, the calculation of a value correlating to the imposed weight enables a simple calculation to be made of the measurement using methods known to the state of the art.
[0019] Furthermore, the building machine according to the present invention comprises an evaluation device, which, according to the measured imposed weight or the physical value correlating to the imposed weight, generates a signal in the operating mode of the lowering of the building machine, referred to below as a control signal, that signals an unwanted and uncontrolled lowering of the building machine, if the imposed weight reaches or falls below a predetermined threshold value, and/or generates a signal that signals a controlled lowering of the building machine if the imposed weight exceeds a predetermined threshold value.
[0020] In this connection, the term “control signal” is understood to represent any value, by which the information of a controlled lowering or an uncontrolled lowering is indicated. In a preferred embodiment, electrical signals are used for the transmission of information, whereby an electrical signal is understood to be either a digital or an analogue signal.
[0021] In a preferred embodiment of the present invention, the control unit for adjusting the height of the machine frame functions together with the evaluation unit in such a way that in the operating mode of the lowering of the building machine any further lowering of the building machine is prevented if the control unit receives a control signal from the evaluation unit indicating that an uncontrolled lowering of the building machine has been signaled. Alternatively, it is also possible not to carry out any height adjustments until the control unit has received a control signal from the control unit indicating a controlled lowering of the building machine.
[0022] A further preferred embodiment provides for a signaling unit having an acoustic and/or a visual signal and/or a tactile signal emitter, with the signaling unit emitting an acoustic and/or a visual and/or a tactile signal if the signaling unit receives a signal from the evaluation unit indicating an uncontrolled lowering of the building machine. Alternatively a controlled lowering can be signaled.
[0023] The automatic interruption or release of the height adjustment and the signaling of an uncontrolled or a controlled lowering can also be combined, so that the machine operator is notified of an action taking place in the machine control system.
[0024] For the purpose of the invention it is not important which parts of the building machine are brought into contact with the ground when the height of the machine frame is being adjusted. In practice, there is above all the danger that the building machine with the working roller is placed on the ground before the working roller has been able to penetrate the ground.
[0025] However, if the working roller is arranged in a roller housing that is open at the bottom, and is closed on at least one side by a height-adjustable edge protection and/or is closed on the front side in the direction of working by a height-adjustable pressure element and/or is closed on the rear side by a height-adjustable stripper device, both the method according to the present invention and the device according to the present invention will prevent the building machine from falling onto the running gears or the working roller if these parts of the working device should become jammed and are then released as the machine frame is lowered.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Below, different embodiments of the present invention are described with reference to the figures.
[0027] These show:
[0028] FIG. 1 a side aspect of a road cutting machine,
[0029] FIG. 2 a block diagram of the control unit, the measuring device, the evaluation unit and the signaling unit of the road cutting machine,
[0030] FIG. 3 a greatly simplified schematic representation of a lifting column and a running gear of the road cutting machine, whereby the running gear rests on the ground and
[0031] FIG. 4 a greatly simplified schematic representation of a lifting column and a running gear of a road cutting machine, with the running gear lifted off the ground.
DETAILED DESCRIPTION
[0032] FIG. 1 shows the side aspect of a road cutting machine, which represents a small cutting machine. The road cutting machine comprises a machine frame 1 , which is supported by a chassis 2 . The chassis comprises running gears 3 , which include one front wheel 3 A and two rear wheels 3 B. In FIG. 1 , only the rear right-hand wheel 3 B is visible. In known building machines, the chassis can comprise, for example, crawler tracks instead of wheels.
[0033] The cutting machine comprises a working device 4 , which is arranged on the machine frame 1 . The working device 4 comprises a working roller, which is in the form of a cutting roller. The cutting roller, which is not visible in FIG. 1 , is arranged in a cutting roller housing 6 of the working device. The cutting roller housing 6 on the left and right side of the direction side of working A is enclosed by an edge protection 7 . In FIG. 1 only the edge protection 7 in the direction of working is visible. At the front side in the direction of working A, the cutting roller housing 6 is enclosed by a pressure element 8 and at the rear side in the direction of working A by a wiper device 9 . Above the cutting roller housing 6 , there is the control stand for the cutting machine with the operator's seat 11 and the control panel 12 .
[0034] The height of the machine frame 1 of the cutting machine is adjustable in relation to the surface 13 of the ground 14 . The device 15 to adjust the height of the machine frame comprises in the direction of working A a left-hand rear lifting column and a right-hand rear lifting column, which support the machine frame. The left-hand lifting column is attached to the left-hand running gear 3 and the right-hand lifting column is attached to the right-hand running gear 3 . FIG. 1 shows only the right-hand lifting column 16 . When the running gears 3 are resting on the ground 14 , the machine frame 1 is raised by the outward and return movements of the lifting columns 16 , which are controlled by a control unit 17 . As the working device 4 is attached to the machine frame 1 , the height of the cutting roller above the surface of the ground can be adjusted by adjusting the height of the machine frame. By adjusting the height of the machine frame, the height of the edge protection 7 , the pressure element 8 and the wiper device 9 , which are also arranged on the machine frame are also adjusted. However, the height of the edge protection, the pressure element and the wiper device is also adjustable in relation to the machine frame. The devices to adjust the height of the edge protection, the pressure element and the wiper device, which are not shown in FIG. 1 , ensure a floating position to the edge protection, the pressure element and the wiper device, in which the edge protection, the pressure element and the wiper device rest on the ground in a floating manner.
[0035] The control device 17 comprises an operating mode, in which the machine frame 1 of the cutting machine is lowered to adjust the cutting depth. This process is also known as “sighting”. The machine operator can engage this operating mode, for example, by activating a control on the control panel 12 , for example a press-button or a switch.
[0036] In addition to the control unit 17 to control the device 4 to adjust the height of the machine frame with the left-hand and the right-hand lifting column 16 , the cutting machine also comprises a measuring device 18 , an evaluation unit 22 and a signaling unit 30 , which are shown in FIG. 2 together with the lifting columns 16 in a block diagram. All units can form separate building elements or can be a part of the central control system of the building machine.
[0037] The lifting columns 16 are hydraulically operated. The hydraulic system is not shown in FIG. 2 . By means of the control unit 17 , the hydraulic lifting columns 16 can be operated in such a way that the lifting columns are moved inwards and outwards allowing the machine frame 1 to be raised or lowered when the running gears 3 are resting on the ground.
[0038] The measuring device 18 comprises means 19 to measure the imposed weight of the cutting machine on the running gears. The means for measuring the imposed load include a first measurement indicator 19 A for measuring the imposed weight on the rear left-hand running gear and a second measurement indicator 19 B for measuring the imposed weight on the rear right-hand running gear. These are described individually in detail below with reference to the FIGS. 3 and 4 .
[0039] The measuring device 18 is connected to the evaluation unit 22 via a data connection 20 , which is in turn connected via a data connection 21 to the control unit. The measurement indicators 19 A, 19 B generate signals on the basis of the imposed load. In simple terms, the measurement indicators generate a signal if the running gear is resting on the ground and it generates no signal if the running gear is not resting on the ground or vice versa. However, the measurement indicators can also generate a signal that is proportional to the size of the imposed weight, for example an alternating voltage, with the amplitude increasing in direct proportion to the imposed weight. The evaluation unit 22 compares the output signal from the first and the second measurement indicators 19 A, 19 B respectively with a threshold value, which, in the simplest case is zero. If the output signal from the first indicator is equal to zero and/or the output signal from the second measurement indicator is equal to zero, the evaluation unit 22 generates a control signal indicating an uncontrolled lowering of the building machine indicating that at least one of the two rear running gears is not resting on the ground. On the other hand, the evaluation unit 22 does not generate the control signal if the output signal from the first and second measurement indicators is greater than zero, i.e. both running gears are resting on the ground. In this case, the evaluation unit 22 can also generate a second control signal that indicates a controlled lowering of the building machine. However, a signal evaluation of this type is to be understood as being only one of a number of possible embodiments, as the generation of corresponding signals and their evaluation belongs as such to the state of the art.
[0040] The signaling unit 30 comprises an acoustic and/or a visual and/or a tactile signal emitter 20 A, 20 B, 20 C. If the signaling unit 30 receives a control signal from the evaluation unit 22 indicating an uncontrolled lowering of the building machine during the operating mode selected by the machine operator for adjusting the cutting depth, the signaling unit sends the machine operator an acoustic and/or a visual and/or a tactile signal, so that he can take the necessary steps to restore the machine to a controlled state.
[0041] By way of example, it is assumed that, in the operating mode for adjusting the cutting depth, the machine operator lowers the machine frame more quickly that the cutting roller can penetrate the ground. Consequently, at least one of the two running gears loses contact with the ground, so that the evaluation unit 22 generates a signal indicating an uncontrolled lowering of the building machine. This is immediately communicated to the machine operator by means of the signaling unit 30 . The machine operator can then restore a controlled lowering by interrupting the lowering of the machine frame immediately, although he can also raise the machine frame again if this should be necessary.
[0042] A further embodiment of the present invention provides for the fact that not only the evaluation unit 22 but also the control unit 17 for adjusting the height of the machine frame 1 receives a control signal indicating an uncontrolled sinking. The control unit is configured in such a way that, after a control signal is received, it can prevent or interrupt any adjustment to the height by the lifting columns 16 . Additionally, the signaling unit 30 can communicate the automatic correction to the machine operator. Moreover, after receiving the control signal, the control unit 17 can intervene further in the control of the machine in order to return the machine to a controlled state, for example, it can lower a running gear 3 that has already been slightly raised until the evaluation unit receives a signal indicating a controlled lowering. These corrections can be made by the control unit on the basis of a predetermined program. This ensures that an uncontrolled lowering can be corrected immediately if the correction is not carried out manually by the machine operator.
[0043] FIGS. 3 and 4 show in a simplified schematic representation one of the two rear lifting columns 16 and the respective running gear 3 , in which one wheel is supposed to be resting on the ground. The lifting column 16 comprises a piston/cylinder arrangement 23 , which is arranged in an upper and a lower conductor pipe 24 , 32 , that concentrically encloses the piston/cylinder arrangement 23 . The upper conductor pipe 24 is connected to the area of the lower part of the machine frame 1 , which is only notionally indicated. On the upper side, the upper conductor pipe 24 is closed by means of a cover 25 , which comprises a bore-hole 26 . The piston 23 B of the piston/cylinder arrangement 23 has, at its upper side, a guiding piece 28 , that can be longitudinally displaced along the bore-hole 26 of the cover 25 . A plate 29 is connected to the upper side of the guiding piece 28 , the diameter of which is greater than that of the bore-hole in the cover. Consequently, the cylinder 23 A can move in both an upwards and a downwards direction in the conductor pipes 24 , 32 within the predetermined area, whereby the size of the gap 31 between the lower side of the plate 29 and the upper side of the lid 25 increases or reduces. When the running gear 3 rests on the ground 14 , the cylinder 23 A is supported with its upper side against the lower side of the cover 25 . FIG. 3 shows the lifting column 16 , when the running gear 3 rests on the ground 14 , while FIG. 4 shows the lifting column once the running gear has lost contact with the ground.
[0044] In the present embodiment, the measurement indicator 19 is, for example, an inductive or a capacitive proximity switch that measures the distance between the lower side of the plate 29 and the upper side of the cover 25 . However, instead of the proximity switch an electrical switching contact can be used, which is closed or opened when an imposed weight is applied by the building machine onto the running mechanism. Together with a distance gauge, the play-free mounting of the piston/cylinder arrangement 23 allows a simple and a reliable means of detecting any uncontrolled lowering of the machine. | A self-propelled building machine, especially a road cutting machine or a surface miner, has a machine frame and a chassis, comprising running gears resting on the ground. In addition, the present invention relates to a method for operating such a building machine. In an operating mode for adjusting the working depth of the working device the imposed weight applied by the building machine on the running gear is measured, whereby depending on the imposed weight either a controlled or an uncontrolled lowering of the building machine is indicated. A measuring device comprises a sensor for measuring the weight imposed by the building machine on at least one of the running gears. Depending on the measured imposed weight, a signal is generated indicating an uncontrolled lowering of the building machine, if the imposed weight falls short of a predetermined value and/or a signal indicating a controlled lowering of the building machine is generated if the imposed weight reaches or exceeds a predetermined threshold value. | 4 |
BACKGROUND OF THE INVENTION
Alkyl amidopropyl betaines in general and cocoamidopropylbetaine (CAPB, CAS 61789-40-0) in particular are known for their mildness and hence are very widely used in personal care and consumer products [“ Encyclopedia of conditioning rinse ingredients ” ed. A. L. L. Hunting, Micelle Press, London (1987), p. 125].
As a result of their superior performance, biodegradability and low toxicology profile, they are used on huge scale in cosmetic industry [X. Domingo, “ Amphoteric Surfactants ” ed. E. G. Lomax, Surfactant Science Series, Marcel Dekker Inc., New York, (1996), Vol. 59, p. 75 and J. G. Weers, J. F. Rathman, F. U. Axe, C. A. Crichlow, L. D. Foland, D. R. Scheuing, R. J. Wiersema and A. G. Zielske, Langmuir, 7, 854-867, (1991)].
A conventional commercial betaine composition typically has the following compositions:
Water
64%
by weight
Betaine
28-29%
by weight
NaCl
5-6%
by weight
Glycerin
0.3%
by weight
Fatty acid
0.5%
by weight
Amidoamine
ca. 0.3%
by weight
Total solids content
ca. 36%
by weight
The solids content represents the sum of the components other than water. The proportions of betaine and sodium chloride arise out of the stoichiometry of the reaction of the fatty amide with tertiary amino group (amidoamine) and sodium chloroacetate according to the equation given below.
A small amount of amidoamine normally remains in the product because the quaternization reaction is incomplete. This proportion can, however, be further reduced by an adapted stoichiometry and reaction procedure. The further typical components like glycerin and fatty acids listed originate from the synthesis of the amidoamine. Small amounts of fatty acids (0.5%) in the betaine composition results from synthesis of amidoamine from the corresponding fatty acid and 3-N,N-dimethylaminopropylamine. Glycerin is present in the betaine composition if the amidoamine is synthesized from triglycerides (coconut or palm oil) and 3-N,N-dimethylaminopropylamine.
It is well known that composition of betaines of the aforementioned type is liquid only below a particular concentration of total solids. For example, at ambient temperature a composition of a betaine of Formula I derived from coconut fatty acids solidifies at a solids content of about 40% by weight. For this reason, conventional, commercial, aqueous solutions of coconut amidopropylbetaine, derived from coconut fatty acids, have total solids concentrations below 40% by weight and in most cases about 35-36% by weight. The maximum achievable concentration of a flowable solution of a betaine decreases as the number of carbon atoms is increased. If the fatty acid mixture contains a higher proportion of unsaturated fatty acids, the concentrations achievable frequently are comparatively higher than those achievable with saturated fatty acids.
Several attempts have been made to create betaines (Formula I) of higher concentration primarily because it has been shown that aqueous betaine composition of higher concentrations is self-preserving. The second obvious motive for preparing betaines of higher concentration is low cost of transportation. U.S. Pat. No. 4,243,549 (1981) describes preparation of high active betaines (33.5% by weight) by blending equivalent amount of ethoxylated alkyl sulphate, the anionic surfactant. Flowable and pumpable high active betaines are reported in German patent DE 3613944. The synthesis described in this patent involves use of solvent and azeotropic removal of water. Another German patent DE 3726322 reveals use of highly acidic pH to create betaines of higher concentration. Use of 3 to 20% by weight of nonionic surfactant is taught by German patent DE 3826654 for making betaines of higher concentration. Reference is made to U.S. Pat. No. 5,354,906 (1994) according to which upto 36% by weight active betaines are produced by addition of 1 to 3% by weight of fatty acids. This results in overall solids content of at least 40% by weight [DE 4207386 (1993); EP 560114 (1993)]. DE 19523477 reports the process of making betaines with active content of 40 to 45% by weight using quaternised salts of tertiary amidoamines that are synthesized from 3-N,N-dimethylaminopropylamine and polycarboxylic acids. Flowable betaines of total solids content of 40-55% by weight are made by incorporation of 1 to 10% by weight of hydroxy carboxylic acids [DE 4408183]. Finally, inclusion of mixture of fatty acids and ethoxylated cocomono glycerides also result in achieving betaines of high activity [DE 4408228].
Thus, it makes sense to create industrially feasible alkylamidopropylbetaines (Formula I) of higher concentration to save on freight charges and to render them self-preserving. The self-preserving nature of high active betaines has been established by performing ‘preservation loading test’ using various types of micro organisms [U.S. Pat. No. 5,354,906 (1994)]. It is an object of the present invention to provide a high active aqueous betaine composition comprising a betaine of the general Formula I with less than 5.0 ppm of free sodium monochloroacetate, a totally undesirable impurity.
It is an object of the present invention to provide a process for preparing a high active aqueous betaine composition comprising a betaine of the general Formula I which obviates steps like filtration, concentration and use of organic solvents for making high active betaines.
It is a further object of the present invention to provide an aqueous betaine composition comprising a betaine of the general Formula I which is self-preserving.
SUMMARY OF THE INVENTION
The present invention provides an aqueous betaine composition comprising a betaine of the general Formula I,
in which R is an alkyl group of coconut fatty acids, preferably hydrogenated coconut fatty acids, or a fatty acid mixture which, on the average, corresponds to coconut fatty acids,
an amidoamine of not more than 1% by weight, a free fatty acid less than 1% by weight, 0 to 4% by weight of glycerin, based on composition, less than 5 ppm of free sodium monochloroacetate and, 0.5 to 3% by weight of N-acyl α-amino acids of Formula III wherein R′ is selected from saturated or unsaturated alkyl group with carbon atoms from 8 to 20 and R″ is selected from H, methyl, ethyl or phenyl,
wherein the composition has a solids content of at least 45% by weight and a pH of 4.5 to 8.
More particularly, the invention relates to aqueous betaine composition comprise a betaine of the aforementioned type with a solids content of at least 45% by weight, 0.5 to 3% by weight of N-acyl α-amino acids and free sodium monochloroacetate content of less than 5.0 ppm. The solids content is defined as the weight which is determined by evaporating sample on a flat glass dish for 2 hours at 105° C.
In the present invention, the high active betaines with solids content of at least 45% by weight are obtained by addition of N-acyl α-amino acids of Formula III to the extent of 0.5 to 3% by weight based on the composition.
N-Acyl α-aminoacids of Formula III, wherein R′ is selected from saturated or unsaturated alkyl group with carbon atoms from 8 to 20 and R″ is selected from H, methyl, ethyl or phenyl.
The high active, self-preserving betaine composition of the present invention is a clear aqueous solution that is pourable and flowable at ambient temperatures. The trace level impurities of 3-N,N-dimethylaminopropylamine and sodium monochloroacetate are less than 5.0 ppm.
DETAILED DESCRIPTION OF THE INVENTION
Alkylamidopropylbetaines are produced by quaternizing the alkylamindopropylamine of Formula II with stoichiometric quantity of sodium monochloro acetate in aqueous medium. The alkylamidopropylamine can be obtained by reacting stoichiometric amounts of fatty acids with 3-N,N-dimethylaminopropylamine or aminolysis of triglycerides with the same amine. Either route works very well and the amidification is normally done at 130-140° C. Depending upon the fatty raw material used the amidoamine of Formula II may contain small amounts of unreacted triglyceride or fatty acids usually around 1% by weight. The amidoamine generated from triglyceride obviously has stoichiometric quantities of glycerin liberated. In the present invention the quaternization of amidoamine of Formula II is done by reacting 1.0 mole with amidoamine with 1.05 to 1.08 mole of sodium monochloroacetate at the temperature of 80-85° C. while maintaining pH between 7.5-8.0 by adding sodium hydroxide solution (45%). The progress of the reaction is monitored by estimating the chloride ion liberated as well as by estimating the unreacted amidoamine. Both analytical parameters ensure the completion of quaternization with free amidoamine around 0.5% by weight. Determination of free amidoamine from aqueous betaine composition is done by extracting and then titrating it against standard acid using potentiometry. The amidoamine is extracted from aqueous betaine composition and then it is determined by titrating against acid using potentiometry. N-acyl α-aminoacid (0.5 to 3% by weight) is added to the reaction mass with the solids content above 45% by weight at 85° C. and the pH is raised to 10-10.5 at 95° C. for four hours. This step is essential for destruction of unreacted sodium monochloraceate and to ensure that free sodium monochloroacetate is less than 5.0 ppm. Free sodium monochloroacetate content was determined by ion chromatography of the solid phase extracted betaine composition using anion exchange column. Finally, the pH of the reaction mass is adjusted to 4.5 to 6.5 by mineral acid and is then cooled while stirring. Adjustment of solids content to at least 45% gives clear, flowable betaine composition. The betaine composition thus obtained has 0.5 to 3% of N-acyl α-aminoacid by weight and betaine content of minimum 35% by weight. The betaine composition thus obtained has cloud point above 40° C. and solidification point ranges between 5 to −10° C. The significance of cloud point is that the product remains clear liquid over a wide range of temperatures that covers the entire globe.
The N-acyl α-aminoacids that are used in the present invention to obtain high active betaines are of Formula III, wherein R′ is selected from saturated or unsaturated alkyl group with carbon atoms from 8 to 20 and R″ is selected from H, methyl, ethyl or phenyl. N-acyl α-aminoacids, particularly in the form of their sodium salts, are widely used because of their outstanding mildness to skin and eyes and biodegradability. They are compatible with cationic as well as amphoteric surfactants and find applications in shampoos, mouth washes and medicated skin cleansers [Spivack, J. D., ‘Anionic Surfactants’ edited by Linfield, W. A., Marcel Dekker New York, 1976, 561-617 and technical literature titled ‘Hamposyl Surfactants’ by Hampshire, Organic Chemicals Division, Texas, USA]. Hence N-acyl α-aminoacids are useful additives compared to the additives that are mentioned in the prior art to achieve flowable high active betaine solutions.
Thus, the process described herein generates high active aqueous betaine composition of Formula I with a composition characterized by solids content of minimum 45% by weight, clear flowing liquid, active betaine content of 35% minimum, sodium chloride content of 6% minimum, free fatty acid content less than 1%, free amidoamine content less than 1% and free sodium monochloroacetate and 3-N,N-dimethylaminopropylamine content less than 5 ppm, solidification point less than 5° C. and cloud point above 35° C.
The betaine composition of the present invention with minimum of 45% solids were subjected to microbial ‘challenge test’ using following microorganisms.
A] Staphylococcus aureus B] Escherichia coli C] Pseudomonas aeruginosa D] Candida albicans E] Aspergillus niger
The high active betaine samples with solids content of 45% minimum were inoculated by 1.0×10 5 -1.0×10 6 cfu/ml organisms of each of the above mentioned. The microbial counts of all the composition of betaines having solids content of at least 45% by weight were found to be less than 10 cfu/ml after 7 days.
Microbial count cfu/ml
Microorganism
0 hours
24 hours
7 days
14 days
Staphylococcus
2.0 × 10 6
<400
<10
<10
aureus ATCC 6538
Escherichia coli
5.0 × 10 5
<400
<10
<10
ATCC 10148
Pseudomonas
<400
<20
<10
<10
aeruginosa
(In-house isolate)
Candida albicans
1.28 × 10 6
1.04 × 10 5
<10
<10
ATCC 10231
Aspergillus niger
5.7 × 10 4
5.6 × 10 3
<10
<10
ATCC 16404
The high active betaine composition of the present invention has the following advantages
As described in the background, N-acyl α-amino acid of Formula III is much more useful additive than those described in the prior art.
The process of the present invention circumvents steps like filtration, concentration and use of organic solvents for making high active betaines.
High active betaine composition of the present invention are self-preserving.
The process yields high active betaine composition with less than 5.0 ppm of free sodium monochloroacetate, a totally undesirable impurity.
The following examples describe in detail the process and the betaine composition of the present invention. These examples are by way of illustrations only and in no way restrict the scope of the invention.
EXAMPLES
Cocofatty acid amidoamine was prepared from cocofatty acid and 3-N,N-dimethylaminopropylamine. 3-N,N-Dimethylaminopropylamine was procured from BASF and sodium monochloroacetate was purchased from Clariant.
Example I
To a stirred mixture of cocofatty acid amidoamine (300 g, 1.0 mole, tertiary nitrogen content of 4.79%, acid value 7.3), glycerin (31.5 g) and water (320 ml) under nitrogen at 65° C., an aqueous solution of sodium monochloroacetate (311.6 g, 40%, 1.07 moles) was added over the period of half an hour. The reaction mixture was stirred for 8 hours at 80-85° C. by maintaining the pH between 7.5 to 8.2 with sodium hydroxide (47% aqueous solution). Cocoyl glycine (6 g) was then added to the reaction mixture and stirring was continued for 8 hours at 95° C. while maintaining pH between 10-10.5. The reaction mass was cooled and the pH was adjusted to 4.5 to 5.5 with hydrochloric acid. The clear product (982 g) so formed had the following composition.
Solids
47.2%
Betaine
35.2%
NaCl
6.9%
Fatty acids
0.8%
Cocoyl glycine
0.6%
Glycerin
3.2%
Amidoamine
0.1%
Sodium monochloroacetate
<5.0 ppm
pH
5.2
Cloud point
>40° C.
Solidification point
<−7° C.
Example II
To a stirred mixture of cocofatty acid amidoamine (298 g, 1.0 mole, tertiary nitrogen content of 4.85%, acid value 4.6), glycerin (32.6 g) and water (341 ml) under nitrogen at 65° C., an aqueous solution of sodium monochloroacetate (311.6 g, 40%, 1.07 moles) was added over the period of half an hour. The reaction mixture was stirred for 8 hours at 80-85° C. by maintaining the pH between 7.5 to 8.2 with sodium hydroxide (47% aqueous solution). Lauroyl glycine (9.7 g) was then added to the reaction mixture and stirring was continued for 8 hours at 95° C. while maintaining pH between 10-10.5. The reaction mass was cooled and the pH was adjusted to 4.5 to 5.5 with phosphoric acid. The clear product (991 g) so formed had the following composition.
Solids
47%
Betaine
35.04%
NaCl
6.46%
Fatty acids
0.5%
Lauroyl glycine
1.0%
Glycerin
3.3%
Amidoamine
0.3%
Sodium monochloroacetate
<5.0 ppm
PH
5.1
Cloud point
>40° C.
Solidification point
<3° C.
Example III
To a stirred mixture of cocofatty acid amidoamine (298 g, 1.0 mole, tertiary nitrogen content of 4.85%, acid value 4.6), glycerin (31.5 g) and water (331 ml) under nitrogen at 65° C., an aqueous solution of sodium monochloroacetate (311.6 g, 40%, 1.07 moles) was added over the period of half an hour. The reaction mixture was stirred for 8 hours at 80-85° C. by maintaining the pH between 7.5 to 8.2 with sodium hydroxide (47% aqueous solution). Oleoyl glycine (9.7 g) was then added to the reaction mixture and stirring was continued for 8 hours at 95° C. while maintaining pH between 10-10.5. The reaction mass was cooled and the pH was adjusted to 4.5 to 5.5 with phosphoric acid. The clear product (987 g) so formed had the following composition.
Solids
47.0%
Betaine
35.23%
NaCl
6.44%
Fatty acids
0.48%
Oleoyl glycine
1.0%
Glycerin
3.2%
Amidoamine
0.25%
Sodium monochloroacetate
<5.0 ppm
PH
5.11
Cloud point
>40° C.
Example IV
To a stirred mixture of cocofatty acid amidoamine (300 g, 1.0 mole, tertiary nitrogen content of 4.79%, acid value 7.3), glycerin (32.5 g) and water (365 ml) under nitrogen at 65° C., an aqueous solution of sodium monochloroacetate (311.6 g, 40%, 1.07 moles) was added over the period of half an hour. The reaction mixture was stirred for 8 hours at 80-85° C. by maintaining the pH between 7.5 to 8.2 with sodium hydroxide (47% aqueous solution). Lauroyl sarcosine (6.1 g) was then added to the reaction mixture and stirring was continued for 8 hours at 95° C. while maintaining pH between 10 −10.5 . The reaction mass was cooled and the pH was adjusted to 4.5 to 5.5 with phosphoric acid. The clear product (1020 g) so formed had the following composition.
Solids
45.4%
Betaine
34.21%
NaCl
6.34%
Fatty acids
0.8%
Lauroyl sarcosine
0.6%
Glycerin
3.2%
Amidoamine
0.25%
Sodium monochloroacetate
<5.0 ppm
PH
4.9
Cloud point
>40° C.
Solidification point
<5° C.
Example V
To a stirred mixture of cocofatty acid amidoamine (300 g, 1.0 mole, tertiary nitrogen content of 4.79%, acid value 7.3), glycerin (30.7 g) and water (300 ml) under nitrogen at 65° C., an aqueous solution of sodium monochloroacetate (311.6 g, 40%, 1.07 moles) was added over the period of half an hour. The reaction mixture was stirred for 8 hours at 80-85° C. by maintaining the pH between 7.5 to 8.2 with sodium hydroxide (47% aqueous solution). Cocoyl glycine (6 g) was then added to the reaction mixture and stirring was continued for 8 hours at 95° C. while maintaining pH between 10-10.5. The reaction mass was cooled and the pH was adjusted to 4.5 to 5.5 with phosphoric acid. The clear product (961 g) so formed had the following composition.
Solids
48.28%
Betaine
35.93%
NaCl
7.0%
Fatty acids
0.8%
Cocoyl glycine
0.6%
Glycerin
3.2%
Amidoamine
0.25%
Sodium monochloroacetate
<5.0 ppm
PH
4.8
Cloud point
>40° C.
Solidification point
<−3° C. | An aqueous composition comprising solution of a betaine of the following general Formula I is disclosed Formula I
in which R is an alkyl group of coconut fatty acids, preferably hydrogenated coconut fatty acids, or a fatty acid mixture which, on the average, corresponds to coconut fatty acids, wherein the solution has a solids content of at least 45% by weight, a pH of 4.5 to 8, an amidoamine content of not more than 1% by weight, and a free fatty acid content less than 1% by weight, an N-acyl α-aminoacids content between 0.5 to 3% by weight and 0 to 4% by weight of glycerin, based on the solution. | 2 |
This invention relates to adaptive pressure compensation control in a motor vehicle automatic transmission, and more particularly, to a control for providing a pressure correction which is linearly related to the required compensation.
Background of the Invention
Automatic transmissions of the type addressed by this invention include several fluid operated torque transmitting devices, referred to herein as clutches, which are automatically engaged and disengaged according to a predefined pattern to establish different speed ratios between input and output shafts of the transmission. The input shaft is coupled to an internal combustion engine through a fluid coupling, such as a torque converter, and the output shaft is mechanically connected to drive one or more vehicle wheels.
The various speed ratios of the transmission are typically defined in terms of the ratio Ni/No, where Ni is the input shaft speed and No is the output shaft speed. Speed ratios having a relatively high numerical value provide a relatively low output speed and are generally referred to as lower speed ratios; speed ratios having a relatively low numerical value provide a relatively high output speed and are generally referred to as upper speed ratios. Accordingly, shifts from a given speed ratio to a lower speed ratio are referred to as downshifts, while shifts from a given speed ratio to a higher speed ratio are referred to as upshifts.
In most transmissions, ratio shifting is carried out by selectively directing the fluid pressure output of a pump, referred to as line pressure, to the various clutches of the transmission through the use of one of more shift valves. To upshift from a lower speed ratio to a higher speed ratio, for example, a respective shift valve is activated (electrically or hydraulically) to initiate the supply of fluid pressure to the upper or target speed ratio (on-coming) clutch. Concurrently, the lower speed ratio (off-going) clutch is released, either by exhausting the fluid pressure supplied to it, or through the provision of a one-way device which overruns when the on-coming clutch achieves the required torque capacity.
It is known that the firmness of a shift can be controlled to a desired value over the life of the transmission through adaptive adjustment of the pressure supplied to the on-coming clutch. In transmissions utilizing a hydraulic accumulator to control the rise in fluid pressure at the clutch, the accumulator back-pressure (trim pressure) can be adjusted to modify the clutch pressure; see for example, the U.S. Pat. No. 4,283,970 to Vukovich, issued Aug. 18, 1981, and assigned to the assignee of the present invention.
In transmissions which provide direct control of the clutch pressure in accordance with a predetermined pressure profile, the scheduled pressure or the supply pressure may be adjusted to modify the clutch pressure; see, for example, the U.S. Pat. No. 4,653,350 to Downs et al., issued Mar. 31, 1987, and also assigned to the assignee of the present invention. In either case, the controlled pressure is scheduled as a combined function of a base pressure value determined by table look-up and an adaptive pressure value based on a deviation between actual and desired shift times observed during a previous shift of the same type.
SUMMARY OF THE PRESENT INVENTION
The present invention is directed to an improved adaptive pressure control which accounts for nonlinearity in the relationship between fluid pressure and shift time. To account for such nonlinearity, the control of the present invention utilizes an empirically derived table of shift time vs. controlled pressure to develop a raw pressure error in lieu of a shift time error. The adaptive pressure correction, in turn, is developed in relation to the cumulative pressure error. This removes the effect of system nonlinearity from the adaptive control, allowing significantly more accurate adaptive convergence than was heretofore achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1a-1b form a schematic diagram of a five-speed automatic transmission controlled in accordance with this invention by a computer-based control unit.
FIG. 2 is a state diagram for the clutches of the transmission depicted in FIGS. 1a-1b.
FIG. 3 is a chart depicting the electrical state changes required for shifting from one speed ratio to another.
FIG. 4 graphically illustrates the change in transmission speed ratio during an upshift.
FIG. 5 graphically illustrates a measured shift time vs. pressure characteristic.
FIG. 6 is a schematic diagram of the control of this invention.
FIGS. 7-8 and 9a-9c depict flow diagrams representative of computer program instructions executed by the control unit of FIG. 1a in carrying out the control of this invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 1a-1b of the drawings, the reference numeral 10 generally designates a motor vehicle drivetrain including an engine 12 and a planetary transmission 14 having a reverse speed ratio and five forward speed ratios. Engine 12 includes a throttle mechanism 16 mechanically connected to an operator manipulated device, such as an accelerator pedal (not shown), for regulating the air intake of the engine. The engine 12 is fueled by a conventional method in relation to the air intake to produce output torque in proportion thereto. Such torque is applied to the transmission 14 through the engine output shaft 18. The transmission 14, in turn, transmits engine output torque to an output shaft 20 through a torque converter 24 and one or more of the fluid operated clutches C1-C5, OC, Reverse clutch CR, and one-way clutches 26-30, such clutches being applied or released according to a predetermined schedule for establishing a desired transmission speed ratio.
Referring now more particularly to the transmission 14, the impeller or input member 36 of the torque converter 24 is connected to be rotatably driven by the output shaft 18 of engine 12 through the input shell 38. The turbine or output member 40 of the torque converter 24 is rotatably driven by the impeller 36 by means of fluid transfer therebetween and is connected to rotatably drive the turbine shaft 42. A stator member 44 redirects the fluid which couples the impeller 36 to the turbine 40, the stator being connected through a one-way device 46 to the housing of transmission 14.
The torque converter 24 also includes a clutch TCC comprising a clutch plate 50 secured to the turbine shaft 42. The clutch plate 50 has a friction surface 52 formed thereon adaptable to be engaged with the inner surface of the input shell 38 to form a direct mechanical drive between the engine output shaft 18 and the turbine shaft 42. The clutch plate 50 divides the space between input shell 38 and the turbine 40 into two fluid chambers: an apply chamber 54 and a release chamber 56.
When the fluid pressure in the apply chamber 54 exceeds that in the release chamber 56, the friction surface 52 of clutch plate 50 is moved into engagement with the input shell 38, thereby engaging the TCC to provide a mechanical drive connection in parallel with the torque converter 24. In such case, there is no slippage between the impeller 36 and the turbine 40. When the fluid pressure in the release chamber 56 exceeds that in the apply chamber 54, the friction surface 52 of the clutch plate 50 is moved out of engagement with the input shell 38, as shown in FIG. 1a, thereby uncoupling such mechanical drive connection and permitting slippage between the impeller 36 and the turbine 40.
The turbine shaft 42 is connected as an input to the carrier Cf of a forward planetary gearset f. The sun Sf is connected to carrier Cf via the parallel combination of one-way clutch F5 and friction clutch OC. The clutch C5 is selectively engageable to ground the sun Sf. The ring Rf is connected as an input to the sun S1r of a compound rearward planetary gearset r via the parallel combination of one-way clutch F1 and friction clutch C3. The clutch C2 selectively connects the forward gearset ring Rf to rearward gearset ring Rr, and the Reverse clutch CR selectively grounds the ring Rr. The sun S2r is selectively grounded by clutch C4 or by clutch C1 through the one-way clutch F2. The pinion Pr mechanically couples the pinion gears and is connected as an output to shaft 20.
The various speed ratios and the clutch states required to establish them are set forth in the chart of FIG. 2. Referring to that Figure, it is seen that the Park/Neutral condition is established by releasing all of the clutches with the exception of clutch OC. A garage shift to Reverse is effected by engaging the C3 and CR clutches. In the forward speed ranges, a garage shift to 1st is effected by engaging the clutches C1 and C4. In this case, the forward gearset f is locked up and the one-way clutch F1 applies the turbine speed Nt as an input to the sun element Sr of rearward gearset r, providing a Ni/No ratio of 3.61.
As the vehicle speed increases, an upshift from 1st to 2nd is effected simply by engaging clutch C2; the one-way clutch F1 overruns as soon as on-coming clutch C2 develops sufficient torque capacity. The forward gearset f remains locked up, and the clutch C2 applies the turbine speed Nt as an input to the ring element Rr of rearward gearset r to provide a Ni/No ratio of 1.85. Downshifting from 2nd to 1st merely involves releasing clutch C2.
The upshift from 2nd to 3rd is effected by engaging clutch C5 and releasing clutch OC so that the forward gearset operates as an overdrive, thereby providing a Ni/No ratio of 1.37. Downshifting from 3rd to 2nd is effected by releasing clutch C5 and engaging clutch OC to return the forward gearset f to a lock-up condition.
The upshift from 3rd and 4th is effected by releasing clutch C5 and engaging clutch OC to return the forward gearset f to a lock-up condition, while releasing clutch C4 and engaging clutch C3 to lock-up the rearward gearset r, one-way clutch F2 releasing the rear planet axis Pr. In this case, the turbine speed Nt is transmitted directly to output shaft 20 for a Ni/No ratio of 1.00. The downshift 4th to 3rd is effected by releasing clutch OC and engaging clutch C5 to return the forward gearset f to an overdrive condition, while releasing clutch C3 and engaging clutch C4 to apply the turbine speed Nt as an input to the ring element Rr.
Completing the shift analysis, the upshift from 4th to 5th is effected by engaging clutch C5 (and releasing clutch OC if engine braking is selected) to operate the forward gearset f in an overdrive condition, thereby providing a Ni/No ratio of 0.74. Downshifting from 5th to 4th is effected by releasing clutch C5 (and engaging clutch OC if engine braking is selected).
A positive displacement hydraulic pump 60 is mechanically driven by the engine output shaft 18. Pump 60 receives hydraulic fluid at low pressure from the fluid reservoir 64 and filter 65, and supplies line pressure fluid to the transmission control elements via output line 66. A pressure regulator valve (PRV) 68 is connected to the pump output line 66 and serves to regulate the line pressure by returning a controlled portion of the line pressure to reservoir 64 via the line 70. The PRV 68 is biased at one end by orificed line pressure in line 71 and at the other end by the combination of a spring force, a Reverse ratio fluid pressure in line 72 and a controlled bias pressure in line 74.
The Reverse fluid pressure is supplied by a Manual Valve 76, described below. The controlled bias pressure is supplied by a Line Pressure Bias Valve 78 which develops pressure in relation to the current supplied to electric force motor 80. Line pressure is supplied as an input to valve 78 via line 82, a pressure limiting valve 84 and filter 85. The limited line pressure, referred to as ACT FEED pressure, is also supplied as an input to other electrically operated actuators of the control system via line 86. With the above-described valving arrangement, it will be seen that the line pressure of the transmission is electrically regulated by force motor 80.
In addition to regulating line pressure, the PRV 68 develops a regulated converter feed (CF) pressure for the torque converter 24 in line 88. The CF pressure is supplied as an input to TCC Control Valve 90, which, in turn, directs the CF pressure to the release chamber 56 of torque converter 24 via line 92 when open converter operation is desired. In this case, the return fluid from torque converter 24 is exhausted via line 94, the TCC Control Valve 90, an oil cooler 96 and an orifice 98.
When closed converter operation is desired, the TCC Control Valve 90 exhausts the release chamber 56 of torque converter 24 to an orificed exhaust 100, and supplies a regulated TCC apply pressure in line 102 to the apply chamber 54, thereby engaging the TCC. The TCC apply pressure in line 102 is developed from line pressure by a TCC Regulator Valve 104.
Both the TCC Control Valve 90 and the TCC Regulator Valve 104 are spring biased to effect the open converter condition, and in each case, the spring force is opposed by an electrically developed control pressure in line 106. The control pressure in line 106 is developed by the solenoid operated TCC Bias Valve 108, through a ratiometric regulation of the fluid pressure in line 110.
When closed converter operation is desired, the solenoid of TCC Bias Valve 108 is pulse-width-modulated at a controlled duty cycle to ramp up the bias pressure in line 106. Bias pressures above the pressure required to shift the TCC Control Valve to the closed-converter state are used to control the TCC apply pressure developed in line 102 by TCC Regulator Valve 104. In this way, the TCC Bias Valve 108 is used to control the torque capacity of the TCC when closed converter operation is desired.
The friction clutches C1-C5, OC and CR are activated by conventional fluid operated pistons P1-P5, POC and PCR, respectively. The pistons, in turn, are connected to a fluid supply system comprising the Manual Valve 76 referred to above, the Shift Valves 120, 122 and 124, and the Accumulators 126, 128 and 130. The Manual Valve 76 develops supply pressures for Reverse (REV) and the various forward ranges (DR, D32) in response to driver positioning of the transmission range selector 77. The REV, DR and D32 pressures, in turn, are supplied via lines 72, 132 and 134 to the various Shift Valves 120-124 for application to the fluid operated pistons P1-P5, POC and PCR. The Shift Valves 120, 122 and 124 are each spring biased against controlled bias pressures, the controlled bias pressures being developed by the solenoid operated valves A, C and B. The accumulators 126, 128 and 130 are used to cushion the apply, and in some cases the release, of clutches C5, C2 and C3, respectively.
A chart of the ON/OFF states of valves A, C and B for establishing the various transmission speed ratios is given in FIG. 3. In Neutral and Park, the solenoids A, B and C are all off. In this condition, line pressure is supplied to clutch piston POC through orifice 176, but the remaining clutches are all disengaged. Reverse fluid pressure, when generated by Manual Valve 76 in response to driver displacement of range selector 77, is supplied directly to clutch piston P3 via lines 72, 73 and 140, and to clutch piston PCR via lines 72, 142, orifice 144 and Shift Valve 124.
A garage shift to the forward (Drive) ranges is effected when Manual Valve 76 is moved to the D position, connecting line pressure to the DR pressure supply line 132. The DR pressure is supplied to the clutch piston P1 via line 146 and orifice 148 to progressively engage clutch C1. At the same time, Solenoid Operated Valves A and C are energized to actuate Shift Valves 120 and 122. The Shift Valve 122 directs DR pressure in line 132 to clutch piston P4 via Regulator Valve 150 and line 152. The Shift Valve 120 supplies a bias pressure to the Regulator Valve 150 via line 154 to boost the C4 pressure. In this way, clutches C1, C4 and OC are engaged to establish 1st speed ratio.
Referring to the chart of FIG. 3, a 1-2 upshift is effected by deenergizing Solenoid Operated Valve A to return Shift Valve 120 to its default state. This routes DR pressure in line 132 to the clutch piston P2 via Shift Valve 120, lines 156, 158 and 162, and orifice 160 to engage the clutch C2. Line 162 is also connected as an input to accumulator 128, the backside of which is maintained at a regulated trim pressure developed by valve 164. The engagement of clutch C2 is thereby cushioned as the C2 apply pressure, resisted by spring force and the trim pressure, strokes the piston of accumulator 128. Of course, a 2-1 downshift is effected by energizing the Solenoid Operated Valve A.
Referring again to the chart of FIG. 3, a 2-3 upshift is effected by energizing Solenoid Operated Valve B to actuate the Shift Valve 124. This exhausts the clutch piston POC via orifice 166 to release the clutch OC, and supplies line pressure in line 66 to clutch piston P5 via orifice 168 and line 170 to progressively engage clutch C5. Line 170 is connected via line 172 as an input to accumulator 126, the backside of which is maintained at the regulated trim pressure developed by valve 164. The engagement of clutch C5 is thereby cushioned as the C5 apply pressure, resisted by spring force and the trim pressure, strokes the piston of accumulator 126. Of course, a 3-2 downshift is effected by deenergizing the Solenoid Operated Valve B.
Referring again to the chart of FIG. 3, a 3-4 upshift is effected by deenergizing Solenoid Operated Valves B and C to return Shift Valves 124 and 122 to their default positions, as depicted in FIGS. 1a-1b. The Shift Valve 124 thereby (1) exhausts clutch piston P5 and accumulator 126 via line 170 and orifice 174 to release clutch C5, and (2) supplies pressure to clutch piston POC via lines 66 and 171 and orifice 176 to engage clutch OC. The Shift Valve 122 (1) exhausts clutch piston P4 via line 152 and orifice 178 to release clutch C4, and (2) supplies DR pressure in line 132 to clutch piston P3 via Shift Valve 120, orifice 180 and lines 182, 184, 73 and 140 to engage clutch C3.
Line 182 is connected via line 186 as an input to accumulator 130, the backside of which is maintained at the regulated trim pressure developed by valve 164. The engagement of clutch C3 is thereby cushioned as the C3 apply pressure, resisted by spring force and the trim pressure, strokes the piston of accumulator 130. Of course, a 4-3 downshift is effected by energizing the Solenoid Operated Valves B and C.
Referring again to the chart of FIG. 3, a 4-5 upshift is effected by energizing Solenoid Operated Valve B to actuate the Shift Valve 124. This exhausts the clutch piston POC via orifice 166 to release the clutch OC, and supplies line pressure in line 66 to clutch piston P5 via orifice 168 and line 170 to progressively engage clutch P5. As indicated below, line 170 is also connected via line 172 as an input to accumulator 126, which cushions the engagement of clutch C5 as the C5 apply pressure, resisted by spring force and the trim pressure, strokes the piston of accumulator 126. Of course, a 5-4 downshift is effected by deenergizing the Solenoid Operated Valve B.
The Solenoid Operated Valves A, B and C, the TCC Bias Valve 108 and the Line Pressure Bias Valve 78 are all controlled by a computer-based Transmission Control Unit (TCU) 190 via lines 192-196. As indicated above, the valves A, B and C require simple on/off controls, while the valves 108 and 78 are pulse-width-modulated (PWM). The control is carried out in response to a number of input signals, including an engine throttle signal %T on line 197, a turbine speed signal Nt on line 198 and an output speed signal No on line 199. The throttle signal is based on the position of engine throttle 16, as sensed by transducer T; the turbine speed signal is based on the speed of turbine shaft 42, as sensed by sensor 200; and the output speed signal is based on the speed of output shaft 20, as sensed by sensor 202. In carrying out the control, the TCU 190 executes a series of computer program instructions, represented by the flow diagrams of FIGS. 7-8 and 9a-9c described below.
As indicated above, the present invention concerns the development of an adaptive correction for a predetermined pressure schedule as a means of compensating for variability due to tolerance variations, wear, etc. As set forth in the above-referenced Vukovich and Downs et al. patents, shift quality may be judged by comparing a measure of the actual shift time with a reference or desired time. If the measured shift time is significantly greater than the desired shift time under normal shift conditions, the pressure correction adds to the scheduled pressure during the next such shift to reduce the shift time. If the measured shift time is significantly less than the desired shift time, the pressure correction subtracts from the scheduled pressure during the next such shift to increase the shift time. Over a number of shifts, the pressure correction compensates for various sources of error, and the measured shift time is brought into correspondence with the desired shift time.
The measured shift time is most precisely characterized in terms of the time required for the transmission speed ratio to change from its pre-shift value to its post-shift value. This interval is customarily referred to in the art as the inertia phase of the shift. FIG. 4 depicts the progression of the transmission speed ratio from 2nd to 3rd in the course of a 2-3 upshift. To avoid nonlinearity in the initial and final stages of ratio progression, the shift time is preferably defined as the time elapsed during a predetermined intermediate portion of the ratio progression. Referring to FIG. 4, the shift time is defined in the illustrated embodiment as the interval ta-tb, the ratio progression being 20% complete at time ta and 80% complete at time tb.
As indicated above, a difficulty in developing a suitable pressure correction based on the deviation of the measured shift time from a desired shift time is that the relationship between shift time and control pressure is typically nonlinear. In the above-referenced patent to Downs et al., the pressure correction gain table compensates for nonlinearities at a given desired shift time. However, the desired shift time changes with operating conditions, and the nonlinearities cannot be modeled by a single gain table. This is illustrated in FIG. 5, where the solid trace depicts measured shift time as a function of the controlled pressure. A first shift having a desired shift time of DSTa, a measured shift time of MSTa, and thus, a shift time error of DELTA, occurs due to a pressure error of PEa. A second shift having a desired shift time of DSTb, a measured shift time of MSTb, and the same shift time error of DELTA, occurs due to a pressure error of PEb which is much larger than PEa. Clearly, different pressure corrections are required to correct a given shift time error, depending on the desired shift time.
The above-described difficulty is overcome, according to the present invention, by storing within control unit 190 a representation of the empirically derived function depicted in FIG. 5, and applying the measured and desired shift times to the stored function to determine the required pressure correction (error) directly. The determined pressure error is apportioned among low and high shift torque adaptive correction cells and cell error values are integrated to develop adaptive correction values.
A schematic diagram of the control of this invention is depicted in FIG. 6. The blocks 220 and 222 determine an overall pressure error PE upon completion of each scheduled upshift. The block 220 provides a desired shift time (DST) as a function of the target speed ratio Rdes and an estimate of the shift torque, STQ. The shift torque STQ is determined according to the sum of the gearset input torque and the inertia torque required to complete the shift. The gearset torque may be computed in relation to the product of the engine output torque and the estimated torque multiplication provided by torque converter 24. The inertia torque may be estimated in relation to the turbine speed Nt at the initiation of the shift. The trace 224 shown within the block 220 represents the stored DST vs. STQ relationship for a given target ratio.
The desired shift time DST developed at block 220, the measured shift time MST and the target speed ratio Rdes are provided as inputs to the block 222 for the purpose of developing the pressure error PE. The block 222 stores an empirically derived relationship between measured shift time MST and transmission line pressure for each target speed ratio, similar to the function depicted in FIG. 5. Both the measured shift time MST and the desired shift time DST are applied to the stored function to determine corresponding line pressure values Pmst and Pdst. The difference between the pressure values (Pmst-Pdst) forms the pressure error output PE. Significantly, the pressure error can be positive or negative, for respectively increasing or decreasing the scheduled line pressure in subsequent shifting of the same type.
The pressure error from block 222 is applied to the error characterization portion of the control, designated generally by the reference numeral 230, which forms high and low pressure correction amounts PChi and PClo based on the pressure error PE. These correction amounts define a two-point table of pressure correction as a function of shift torque STQ. As described below in reference to the flow diagram of FIG. 9, the pressure command during shifting is determined as a combined function of the scheduled base pressure and the correction value determined from the two-point correction table.
The error characterization control portion initially apportions the pressure error PE between high and low pressure error values PEhi and PElo through the operation of blocks 232-238. The blocks 232 and 236 develop low and high cell weight factors LCWF and HCWF in relation to shift torque STQ, and the weight factors LCWF and HCWF are applied to the pressure error PE at blocks 234 and 238 to form the low and high pressure error values PElo and PEhi. The low and high pressure error values PElo and PEhi are individually integrated at blocks 240 and 242, and applied to the gain table of block 244 to form low and high integral factors IFlo and IFhi. The integral factors IFlo and IFhi, in turn, are applied to PElo and PEhi at blocks 246 and 248, respectively, to form the low and high pressure correction terms PClo and PChi.
Referring now to FIGS. 7-8 and 9a-9c, the flow diagram of FIG. 7 represents a main or executive computer program which is periodically executed in the course of vehicle operation in carrying out the control of this invention. The block 240 designates a series of program instructions executed at the initiation of each period of vehicle operation for setting various terms and timer values to an initial condition. Thereafter, the blocks 242-250 are sequentially and repeatedly executed as indicated by the flow diagram lines.
At block 242, the control unit 190 reads the various inputs referenced in FIG. 1a and updates the loop timers, if any. The block 244 determines the desired speed ratio Rdes and required states of solenoids A, B and C for achieving the desired speed ratio. The desired ratio Rdes may be determined in a conventional manner as a predefined function of engine throttle position TPS and vehicle speed Nv.
The block 246, described in further detail in the flow diagram of FIG. 8, determines the desired line pressure LPdes. The block 248 converts the desired line pressure LPdes to a PWM duty cycle for force motor 80, and suitably energizes the various electro-hydraulic elements, including the force motor 80, the TCC solenoid valve 108, and shift valve solenoids A, B and C. The block 250, described in further detail in the flow diagram of FIGS. 9a-9c, develops adaptive pressure corrections as described above with respect to the control system diagram of FIG. 6.
Referring to the line pressure determination flow diagram of FIG. 8, the block 260 is first executed to determine if the transmission is in a nonshifting mode, an engine braking mode, or if a garage shift is in progress. If any of these conditions are true, the block 262 is executed to determine the desired line pressure LPdes using mode-specific look-up tables, not described herein. Otherwise, the transmission is in a shifting mode, and the blocks 264-270 are executed to look-up the base line pressure LPdes as a function of shift torque STQ and vehicle speed Nv, to apply the appropriate offsets, and to look-up and apply the adaptive correction amount LPad.
The offsets identified in block 266 include a downshift offset OSds and a temperature offset OStemp. The downshift offset OSds is determined as a function of gear and vehicle speed Nv, and the temperature offset OStemp is determined as a function of the transmission oil temperature.
As noted above with respect to the control system diagram of FIG. 6, the adaptive pressure correction LPad is determined as a function of the shift torque STQ and the target speed ratio. This look-up involves an interpolation between the high and low pressure correction values PChi and PClo defined in reference to FIG. 6.
In the adaptive update flow diagram of FIGS. 9a-9c, the control unit 190 measures the shift time ta-tb as defined in reference to FIG. 4, and develops the high and low pressure correction terms PChi and PClo defined in reference to FIG. 6. If a single ratio upshift is not in progress, as determined at block 282, further execution of the routine is skipped, as indicated by the flow diagram line 284. Once it is determined that an upshift is in progress, the block 286 is executed to determine if the percentage of ratio completion (RATCOMP) is at least 20%.
When RATCOMP first reaches 20%, as determined at block 288, the block 290 is executed to initialize a SHIFT TIMER for measuring the shift time ta-tb. When RATCOMP reaches 80%, as determined at block 292, the blocks 294-298 are executed to reset the SHIFT IN PROGRESS indicator, to stop the SHIFT TIMER, and to look-up a desired shift time DST in relation to the shift torque STQ and the target speed ratio Rdes, as described in reference to block 220 of FIG. 6. In addition, the block 300 determines the pressures Pmst and Pdst corresponding to the measured shift time MST and the desired shift time DST, as described in reference to block 222 of FIG. 6, and the block 302 determines the overall pressure error PE according to the difference (Pmst-Pdst). This difference may be positive or negative for increasing or decreasing the base pressure command defined at block 264 of FIG. 8.
Turning to FIGS. 9b-9c, the blocks 320-322 are first executed to zero the overall pressure error PE if its value lies within a deadband defined by ±db. The blocks 324-326 are then executed to apportion the overall pressure error between low and high pressure error cells PElo and PEhi, based on the low and high cell weight factors LCWF and HCWF. The weight factors, as indicated at blocks 232 and 236 of FIG. 6, are determined in relation to the shift torque STQ.
The blocks 328-334 compare the low cell pressure error PElo with a low cell adaptive correction integrator term ACIlo. If PElo is significantly negative, but ACIlo is positive, as determined at blocks 328-330, the block 336 is executed to reset ACIlo to zero. Similarly, if PElo is significantly positive, but ACIlo is negative, as determined at blocks 332-334, the block 338 is executed to reset ACIlo to zero. Otherwise, block 340 is executed to add PElo to ACIlo, updating the integrator term.
The blocks 342-348 compare the high cell pressure error PEhi with a high cell adaptive correction integrator term ACIhi. If PEhi is significantly negative, but ACIhi is positive, as determined at blocks 342-344, the block 350 is executed to reset ACIhi to zero. Similarly, if PEhi is significantly positive, but ACIhi is negative, as determined at blocks 346-348, the block 352 is executed to reset ACIhi to zero. Otherwise, block 354 is executed to add PEhi to ACIhi to update the integrator term.
The blocks 328-338 and 342-352, taken together, operate to reduce the influence of spurious data in the determination of pressure error PE. By resetting the integrator terms when the respective error cells suddenly change sign, adaptive pressure corrections based on the suspect pressure error information is avoided.
The block 358 is then executed to determine low and high integrator factors IFlo and IFhi based on ACIlo and ACIhi, respectively, as described in reference to the block 244 of FIG. 6. The blocks 360-362 then apply IFlo and IFhi to the respective low and high pressure error cells PElo and PEhi to form low and high pressure correction terms PClo and PChi. Finally, the block 364 is executed to store the pressure correction terms PClo and PChi as a function of the target speed ratio Rdes, updating the two-point adaptive pressure correction table addressed at block 268 in FIG. 8.
While this invention has been described in reference to the illustrated embodiment, it is expected that various modifications will occur to those skilled in the art. In this regard, it should be realized that controls incorporating such modifications may fall within the scope of this invention, which is defined by the appended claims. | An improved adaptive pressure control which accounts for nonlinearity in the relationship between fluid pressure and shift time. To account for nonlinearity in the relationship between cumulative shift time error and corrective pressure, the control utilizes an empirically derived table of shift time vs. controlled pressure to develop a raw pressure error in lieu of a shift time error. The adaptive pressure correction, in turn, is developed in relation to the cumulative pressure error. This removes the effect of system nonlinearity from the adaptive control, allowing more accurate adaptive convergence than was heretofore achieved. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a division of U.S. application Ser. No. 406,484 filed Aug. 9, 1982, now U.S. Pat. No. 4,501,236, issued Feb. 26, 1985.
FIELD OF INVENTION
The invention is in the field of reciprocating piston internal combustion engines having piston and cylinder structures shaped to reduce damage associated with detonation and/or destructive knock.
BACKGROUND OF INVENTION
The thermal efficiency of an Otto cycle internal combustion engine depends on the compression ratio. An increase in the compression ratio increases the thermal efficiency of the engine and frequently entails an increase in the tendency of the engine to knock. Compression ratios of the spark ignition engine are now limited by knock.
The knock in internal combustion engines is associated with the sounds that are created by the engines. Knock associated phenomena can sometimes destroy an engine within minutes. Destructive knock may be associated with detonation during the combustion of the fuel in the combustion chamber.
Flames in the combustion chamber may propagate through the combustible mixtures either as deflagrations or as detonations or they may originate at spontaneous ignition sites. Deflagrations are subsonic and associated with small spatial pressure variations. Detonations are supersonic. They are associated with large pressure discontinuities and impact pressures. The pressure discontinuities and impact pressures can cause the damage associated with knock.
Conventional combustion chamber design is such as to promote turbulence. The cross sectional area of the combustion chamber decreases in the region of the end gas to produce a quench or squish zone. Without turbulence, the highly agitated motion of the fuel air mixture, slow combustion would result in inefficient operation of the engine. This shape of the combustion chamber does not inhibit detonation.
Detonation in an internal combustion engine chamber produces sound and pressure stresses. Various devices have been proposed to eliminate detonation by attenuating the high amplitude of these pressure stresses. Bodine, in U.S. Pat. No. 2,760,472, utilizes a sound wave absorber pad between the block and the head to attenuate the high amplitude detonation into sound waves. The piston has a truncated inverted cone shape. Kydel et al. discloses, in U.S. Pat. No. 2,826,185, an internal combustion engine having a piston equipped with a projection. The projection is mounted on top of the mid-section of the piston and has downwardly and outwardly sloping flat surfaces. The head is provided with a firing chamber that decreases in size toward the center of the piston. Polza, in U.S. Pat. No. 2,969,786, shows an internal combustion engine having a piston with an angularly related face providing a firing chamber adjacent to a spark plug. Burnham, in U.S. Pat. No. 4,046,116, shows a piston for an internal combustion engine carrying a plate to increase the compression ratio of the engine. The plate has an upwardly sloping side wall facing the valves to provide clearance for the valves. Takeshi, in U.S. Pat. No. 4,162,661, shows a piston for an internal combustion engine having two separate raised portions located at two peripheral portions of the top of the piston. The ends of the raised portions have concave surfaces to provide for mixing of an air/fuel mixture to enhance combustion and increase engine output power. Thery, in U.S. Pat. No. 4,235,203, shows a two-zone combustion chamber formed by a piston having an upwardly directed projecting part that divides the combustion chamber into two portions. The projecting part has a channel providing communication between the parts of the combustion chamber. These piston structures and combustion chamber shapes have some effect on detonation, but do not control detonation to allow high compression ratios without damage to the piston and head.
SUMMARY OF INVENTION
The invention is directed to a method and piston and cylinder structure of an internal combustion engine for preventing destructive detonation in the combustion chamber of the internal combustion engine. The combustion chamber of the invention formed by the piston face and head has a configuration that attenuates detonation during the combustion episode of an internal combustion engine.
In the method of reducing detonation in an internal combustion engine, the air/fuel mixture is introduced into the combustion chamber during the intake stroke of the piston means. The piston means compresses the air/fuel mixture. A spark ignites the compressed air/fuel mixture causing combustion or burning of the air/fuel mixture. The burning rate of the air/fuel mixture is dependent on turbulent gas flow motions. The turbulence affects flame speed and detonation. The flame front moves across the combustion chamber. During this movement, there is an abrupt increase in the cross sectional area of the combustion chamber in the direction of the flame travel causing an attenuation of the detonation wave and/or an incipient detonation wave, thereby inhibiting damaging knock. In one embodiment of the method, the flame front initially is directed into diverging paths, including a central path, which is divided into secondary diverging paths. At the terminal portions of all the paths, there is an abrupt increase in the cross sectional area in the direction of the flame travel, of the combustion chamber, causing an attenuation of the detonation wave or of an incipient detonation wave, thereby inhibiting damaging knock. The burning fuel mixture forms an expanding gas that is utilized in the power stroke of the engine. The cycle of the engine is completed by the exhausting of the gas in the cylinder prior to a subsequent intake of the next air/fuel mixture.
According to the invention, there is provided a cap means for a piston of an internal combustion engine provided with an abrupt angled wall providing an abrupt increase in the cross sectional area of the combustion chamber in the direction of the flame travel across the combustion chamber which attenuates detonation and/or incipient detonation. In one embodiment, the wall extends transversely across the diameter of the top of the piston and has an angle of substantially 90 degrees with respect to the top of the piston. In another embodiment, the wall has a convex curve with a radius of curvature centered at the electrodes of the spark plug. The wall curves across the mid-section of the top of the piston and has an angle of substantially 90 degrees with respect to the top of the piston. The angle of the wall with respect to the top of the piston can have an angle of more than 90 degrees and still achieve an abrupt increase in the cross sectional area of the combustion chamber in the direction of movement of the flame front. The cap means can be secured to the top of a piston or be integral with the top of the piston. The cap means can have one or more divergent channels providing paths for dissipating detonation in an internal combustion engine. The channels terminate at the abrupt transverse wall providing an abrupt increase in the cross sectional area of the combustion chamber in the direction of the flame travel across the entire chamber, which attenuates detonation and/or incipient detonation.
A specific embodiment of the internal combustion engine has cylinder means with inside cylindrical walls surrounding piston means. Head means mounted on the cylinder means form with the piston means a combustion chamber. Spark generating means, such as a spark plug, mounted on the head means are operable to provide electrical energy to ignite a compressed air/fuel mixture in the combustion chamber. Cap means secured to or part of the top of the piston means has an abrupt step extended across the top of the piston generally normal to the direction of movement of the flame front, which results in attenuation of detonation and/or incipient detonation.
The cap means may have an upwardly and inwardly inclined front face directly opposite the ignition electrodes of a spark plug or means for generating an ignition spark. The front face may merge with a downwardly or inwardly inclined rear face. The rear face joins a transverse wall extended across the piston top. The transverse wall extends in the direction of movement of the piston generally normal to the top of the piston. The front face has a central concave diverging channel and rearwardly converging arcuate walls which extend from opposite sides of the central channel to opposite ends of the transverse wall. The rear face has a pair of diverging channels located on opposite sides of the center portion of the cap means. The second channels extend to the transverse wall. The flame front initially emanates from the region of the spark electrodes. The flame front moves upwardly through the path formed by the central channel and outwardly and rearwardly through side paths adjacent side walls to the rear face. The flame front then moves over the transverse wall and is subjected to retardation due to the abrupt increase in the cross sectional area of the combustion chamber in the direction of flame travel. This causes the attenuation of the detonation and/or incipient detonation to permit the engine to operate at higher compression ratios, thus, without concomitant damage increasing the thermal efficiency of the engine without damaging it.
IN THE DRAWINGS
FIG. 1 is a fragmentary sectional view through a cylinder of a prior art internal combustion engine;
FIG. 2 is a diagram of normal flame speed behavior within a cylinder of an internal combustion engine;
FIG. 3 is a top plan view of an Otto cycle internal combustion engine having the piston and combustion chamber of the invention;
FIG. 4 is an enlarged fragmentary sectional view taken along the line 4--4 of FIG. 3;
FIG. 5 is a sectional view taken along the line 5--5 of FIG. 4;
FIG. 6 is a sectional view taken along the line 6--6 of FIG. 4;
FIG. 7 is a top plan view of the piston of FIG. 6;
FIG. 8 is a perspective view of the valve side of the piston and cap secured to the top of the piston of FIG. 4;
FIG. 9 is a perspective view similar to FIG. 8 of the spark plug side of the piston and cap thereon;
FIG. 10 is a vertical diagram of the combustion chamber with the piston at top dead center;
FIG. 11 is a horizontal diagram of the combustion chamber with the piston at top dead center;
FIG. 12 is a cylinder pressure-volume diagram comparing the engine of the invention with a prior art internal combustion engine;
FIG. 13 is a perspective view of a modification of the cap adapted to be secured to the top of a piston of an internal combustion engine;
FIG. 14 is a top plan view of a piston equipped with the cap of FIG. 13; and
FIG. 15 is a sectional view similar to FIG. 14 showing a piston equipped with the cap of FIG. 13.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1, there is shown a fragmentary sectional view of a piston and cylinder structure of a conventional internal combustion engine. The engine has a block 10 having an upright cylindrical inside wall 11. A cylindrical piston 12 is located in sliding reciprocating engagement with inside wall 11. Piston 12 is connected to a piston rod 13, which has the usual bearing connection with a crankshaft (not shown). A head 14 is located over the block 10. Conventional head bolts (not shown) attach the head 14 to block 10. Head 14 has a generally cone-shaped combustion chamber 16 located in alignment with the top of piston 12. An intake valve 17 reciprocally mounted on head 14 is operable in response to a rotating cam to selectively open and close intake passage 18 for carrying an air/fuel mixture to combustion chamber 16. An exhaust valve 19 mounted for reciprocal motion on head 14 is operable to selectively open and close exhaust passage 21 for carrying exhaust gases from combustion chamber 16 to an exhaust manifold (not shown). A second rotating cam (not shown) is operable to reciprocate exhaust valve 19.
A spark plug 22 is mounted on head 14 between the valves 17 and 19. Spark plug 22 has spaced electrodes 23 and 24 located in the central top portion of combustion chamber 16. When an electric potential is supplied to spark plug 22, an ignition spark between electrodes 23 and 24 ignites the air/fuel mixture in combustion chamber 16. The ignition of the air/fuel mixture in the combustion chamber 16 originates at spark plug electrodes 23 and 24 and radiates therefrom in a flame front. The flame front, illustrated as line 25 in FIG. 2, is divided into four combustion stages. In the final stage, the unburned compressed gas sometimes ignites spontaneously before the arrival of the flame front. This is shown in FIG. 1 at 26, and may result in knock.
Referring to FIG. 2, there is shown a graphic representation indicated at 27 of the burning velocity of the air/fuel mixture or flame front in a combustion chamber of an internal combustion engine plotted as a function of the flame radius from the ignition location. The combustion episode in chamber 16 is divided into four stages. The initial stage 1 is the ignition of about 1% of the fuel mass. The second stage II and third stage III is a rapid flame acceleration and exhibits the peak flame speed. In the final stage IV flame speed has a rapid de-acceleration as the flame front interacts with the head block and piston walls. If detonation occurs instead, it moves at supersonic speeds across the combustion chamber. It is accompanied by large pressure differences which can fatigue or damage engine components. Detonation in conventional internal combustion engines is now evited by maintaining the compression ratio at relatively low values. This limits the thermal efficiency of the engine.
Referring to FIGS. 3 and 4, there is shown an internal combustion engine indicated generally at 28 having a block 29 and a head 37 attached to the top of block 29 with a plurality of head bolts 43. Engine 28 is a valve-in-head engine having a plurality of reciprocating pistons 32 operatively connected to a rotating crankshaft (not shown) with connecting rods 35 in a conventional manner. As shown in FIG. 4, block 29 has an upright inside cylindrical wall 31 accommodating a reciprocating piston 32. Piston 32 has a generally flat circular top wall or face 33 and a cylindrical side wall 34 located in close proximity to the inside cylindrical wall 31. Piston rod 35 is connected to wall 34 with a wrist pin 36. A conventional bearing connects rod 35 to the crankshaft whereby, on rotation of the crankshaft, piston 32 reciprocates in the cylinder bore defined by wall 31. The engine has an Otto engine cycle wherein piston 32 has intake, compression, power, and exhaust movements.
As shown in FIG. 4, head 37 has a combustion chamber 42 located over top wall 33 of piston 32. Head 37 has a first generally upright and inwardly inclined wall portion 44 having a threaded hole 46 accommodating a spark plug 47. Spark plug 47 has electrodes 48 and 49 located in combustion chamber 42. Electrodes 48 and 49 are located generally along a diametric upright plane bisecting the top 33 of piston 32. Electrodes 48 and 49 are positioned above an outer edge portion of piston 32.
Head 37 has a second wall portion 51 joined to the upper end of the first wall portion 44. Second wall portion 51 extends downwardly toward the diametrically opposite side of piston 32 to converge the combustion chamber 42 to an area opposite spark plug 47. Wall portion 51 has ports accommodating intake and exhaust valves. FIG. 4 shows the intake valve 52 reciprocally mounted on head 37 for movement between the closed position shown in full lines and an open position shown in broken lines. Conventional rotating cam and rocker arm structures are used to reciprocate valve 52. Valve 52 has a cylindrical head 53 joined to a stem 54. Head 53 engages an annular valve seat 55 to close the intake passage 56 leading from intake manifold 38 to combustion chamber 42. When valve 52 has been moved to the open position, as shown in broken lines, the fuel/air mixture flows through passage 56 into combustion chamber 42. Head 37 is provided with an exhaust valve similar to valve 52. The exhaust valve is operable to move between open and closed positions to provide for the flow of exhaust gases from combustion chamber 42.
Referring to FIGS. 4-9, a cap or member indicated generally at 57 is secured to the top of piston 32 with a plurality of bolts 58. The bolts 58 extend upwardly through the top wall 33 of piston 42 and are threaded into suitable holes in cap 57. Other means, such as adhesives, can be used to secure cap 57 to top wall 33 of piston 32. Cap 57 can be integral with the top of piston 32 so that the piston and the cap are a one-piece unit.
As shown in FIGS. 7, 8, and 9, the top wall or top 33 of piston 32 has an annular rim 59 surrounding the outer peripheral edge of top wall 33. Cap 57 has a generally flat bottom 61 that is in surface engagement with top wall 33. The outer edge of bottom 61 has an arcuate peripheral shoulder 62 that rests on a portion of rim 59. The top of piston 32 may be flat. The cap for a flat top piston has a flat bottom secured to the piston. Cap 57 can be integral with the top of the piston.
Cap 57 has an upwardly and inwardly directed forward or front, indicated generally at 63, that is joined to a downwardly and inwardly sloping back, indicated generally at 64. Back 64 is joined to an end or wall 66 that forms a step with top wall 33. Wall 66 located generally normal to top wall 33 of piston 32 extends across the diameter of the top of piston 32 generally normal to the direction of movement of the flame front. Wall 66 provides an abrupt increase in the cross sectional area of the combustion chamber portion 42B in the direction of flame travel. Wall 66 has a height of about 5 to 10 mm throughout its diametric length of about 8.5 cm. Other sizes and size relationships may be used to provide wall 66.
As shown in FIGS. 5, 7, 8, 9, and 11, front 63 of cap 57 has a central concave first channel or pocket 67 extended from the lower edge of cap 57 upwardly and inwardly toward the inner edge of the cap. Channel 67 has opposite outwardly curved sides that diverge from the lower edge of the cap. The upper ends of the sides are joined to an inwardly curved upper edge. The curved sides and curved upper edge have substantially the same curve lengths. The mid-portion of the curved upper edge is located at approximately the mid-point of cap 57. The face of the bottom of channel 67 has a generally symmetrical radical concave curvature. The radial concave curvature is larger than the lateral concave curvature. The center of channel 67 is located along and in alignment with the longitudinal axis of spark plug 47. As shown in FIG. 4, front 63 is spaced from electrodes 48 and 49 of spark plug 47 providing combustion chamber 42 with an upwardly and inwardly inclined forward portion 42A. Chamber portion 42A diverges upwardly and inwardly from the outer peripheral edge of the top of cylinder wall 31 when the piston is in the top dead center, as shown in FIG. 4. Back 64 slopes inwardly and downwardly toward transverse wall 66 providing the combustion chamber with a diverging or increasing cross sectional area 42B.
Returning to FIGS. 8 and 9, the front has convex side portions 68 and 69 extended from opposite sides of pocket 67 to the transverse wall 66. Side portions 68 and 69 converge from the side edges of channel 67 to the opposite ends of transverse wall 66.
Back 64 has a pair of shallow concave diverging channels or pockets 71 and 72 separated by a downwardly and inwardly inclined mid-section or rib 74. Channels 71 and 72 are located on opposite sides of a diametrical plane bisecting channel 67 and provide second paths of the flame front and detonation energy. Channels 71 and 72 have identical shapes and curvatures and extend from the top edge of channel 67 to the transverse wall 66. The outside edge of channel 71 joins the upper curved edge of side 68. The outside edge of channel 72 joins the upper edge of side 69.
Referring to FIGS. 10 and 11, there is shown a diagram of the combustion chamber 42 with the piston 32 in the top dead center at the completion of the compression stroke. The air/fuel mixture in combustion chamber 42 has been ignited by an electrical spark generated between the electrodes 48 and 49 of spark plug 47. The initial ignition occurs at the electrodes 48 and 49 and commences a flame front that propagates in an arc from the ignition point in the radial direction from electrodes 48 and 49 across combustion chamber 42.
The flame front moves from first path 79 and side paths 81 and 82 to second paths 83 and 84 provided by channels 71 and 72. Second paths 79 and 81 diverge toward the middle transverse plane of the piston face 33 and terminate at transverse wall 66. The flame front continues along the second portion 42B of the combustion chamber 42 into terminal portion 75 of the combustion chamber. The flame front passes over transverse wall 66. The abrupt or sudden change in the cross sectional area along the path of the flame's travel of chamber 42B after wall 66 causes attenuation of detonation and/or incipient detonation. Channels 76, 71, and 72 and wall 66 increase the turbulence intensity of the air/fuel mixture and, thus, enhance combustion. The turbulent gas motions throughout combustion chamber 42 affect the burning rate of the fuel, as well as the efficiency of the engine. This occurs simultaneously with the attenuation of detonation or incipient detonation. The reduction of detonation or incipient detonation allows the engine to operate at higher compression ratios without incurring damage. The high compression ratios increase the thermal efficiency of the engine.
Referring to FIG. 12, there is shown a pressure-volume diagram for a conventional piston and cylinder of an internal combustion engine and the piston and cylinder equipped with the cap 57 of the invention. The dotted line curve 77 represents the pressure-volume curve in the four stroke cycle of a conventional piston and cylinder arrangement. The full line shows the curve for a piston equipped with the cap 57. There is a substantial increase in the pressure of the air/fuel mixture in the combustion chamber in curve 78 caused by the cap 57. This increase in pressure results in the greater efficiency and output power of the internal combustion engine.
A modification of the cap for a piston of an internal combustion engine of the invention providing an abrupt increase in the cross sectional area of the combustion chamber in the direction of the flame front travel is shown in FIGS. 13-15. Referring to FIG. 13, cap 100 is a one-piece metal member having a generally semi-circular outer edge 101 curved to conform the outside of the top of a piston. Edge 101 has an arc of about 180 degrees. The edge can have an arc that is greater than or less than 180 degrees. Opposite ends of edge 101 are located adjacent diametrically opposite sides of the top of piston 107. Cap 100 has a convex curved front wall 102. A radius center 103 midway between the ends of outer edge 102 determines the radius of the arced front wall 102. Radius center 103 is located in close proximity to the electrodes of the spark plug of the engine. Cap 100 has a generally flat top 104 and a flat bottom 106. The cap 100 has a generally uniform thickness. Preferably, the cap 100 has a thickness of 7 mm. Other thicknesses of the cap can be used.
As shown in FIGS. 14 and 15, cap 100 is located on the top 108 of piston 107. The cap has a plurality of holes 109 accommodating bolts 111 secured to the top of piston 107. Other attaching structures can be used to secure cap 100 to the top 108 of piston 107. Cap 100 can be integral with the metal of piston 107.
Referring to FIG. 15, there is shown an internal combustion engine indicated generally at 112 similar to the engine 28, shown in FIG. 3, having a block 113 and a head 117. Block 113 has a generally upright cylinder 114 reciprocally accommodating piston 107. Piston 107 is attached to a connecting rod 116 operatively connected to a rotating crankshaft (not shown). The upper end of cylinder 114 and head 117 forms a combustion chamber 118 located over the top of piston 107. The head 117 has a threaded hole 119 accommodating a spark plug 121. Spark plug 121 has electrodes 122 and 123 located above an outer edge portion of piston 107. The head 117 has a passage or port 126 terminating in an annular valve seat 124 open to combustion chamber 118. A reciprocating valve indicated generally at 127 cooperates with the head and seat 124 to control the flow of air/fuel mixture into combustion chamber 118. A conventional rotating cam and rocker arm structure (not shown) is used to reciprocate valve 127. Valve 127 has a cylindrical stem 128 integral with an annular head 129. The head 117 is provided with an exhaust valve similar to intake valve 127.
Cap 100, as shown in FIGS. 14 and 15, is secured to the top 108 of piston 107 with the bolts 111. The radius center 103 is located in close proximity to the spark plug electrodes 122 and 123. The outer edge 101 is located in vertical alignment with the outer wall of piston 107. This locates the front wall 102 of cap 100 across the mid-section of piston top 108. The central portion of wall 102 is located slightly forward of the center of top 108. Front wall 102 projects upward generally normal to the top of piston 107 and extends to opposite portions of the piston top.
As shown in FIG. 15, piston 107 is in the top dead position at the completion of the compression stroke. The air/fuel mixture in combustion chamber 118 is compressed and has been ignited by the electrical spark generated between electrodes 122 and 123 of spark plug 121. The initial ignition of the air/fuel mixture occurs at the electrodes 122 and 123 and commences a flame front that propagates in a generally radial direction, indicated by arrows 131 in FIG. 4, along an arc from the ignition point across the combustion chamber 118. The flame front passes over the generally transverse wall 102, thereby suddenly encountering an increase in cross sectional area of the combustion chamber in the direction of the movement of the flame front. The abrupt change in the cross sectional area along the path of the flame front travel of the combustion chamber causes attenuation of detonation and/or incipient detonation. The abrupt change in the cross sectional area of the combustion chamber is generally normal to the direction of movement of the flame front. The reduction of the detonation and incipient detonation allows the engine to operate at a higher compression ratio without incurring damage. The higher compression ratios increase the thermal efficiency of the engine.
While there has been shown and described the several preferred embodiments of the piston, cap, and combustion chamber of the invention, it is understood that changes in the size, shape, and structure may be made by those skilled in the art without departing from the invention. The invention is defined in the following claims. | A method of attenuating detonation in an internal combustion engine having a combustion chamber and a piston reciprocably located in a cylinder forming the combustion chamber. The piston has an air/fuel mixture intake, compression, power, and exhaust movement. An air/fuel mixture is introduced in the combustion chamber during the intake movement of the piston. The air/fuel mixture is compressed in the combustion chamber. The compressed air and fuel is ignited with spark at the completion of the compression movement of the piston causing the air/fuel mixture to burn and establishing a flame front that propagates across the combustion chamber. The combustion chamber abruptly increases in the cross sectional area in the direction of travel of the flame front. The expanding burning air/fuel mixture in the combustion chamber moving across the abrupt increase in cross sectional area of the combustion area attenuates detonation in the combustion chamber. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is entitled to the benefit of and incorporates by reference essential subject matter disclosed in International Patent Application No. PCT/DK2008/000222 filed on Jun. 17, 2008 and German Patent Application No. 10 2007 028 562.2 filed Jun. 19, 2007.
FIELD OF THE INVENTION
[0002] The invention concerns a refrigeration system with a refrigerant circuit, comprising several evaporator paths and a distributor causing a distribution of refrigerant to the evaporator paths, said distributor having a controllable valve for each evaporator path.
BACKGROUND OF THE INVENTION
[0003] Such a refrigeration system is known from DE 195 47 744 A1. The known refrigeration system comprises one single compressor and one single condenser, but two evaporators, which are made separately from one another. The refrigerant flow delivered by the compressor is divided into two partial flows after the condenser and before the expansion valves by means of a 3/2-way valve, whose position is controlled by a control unit. This embodiment, however, only permits dividing the refrigerant flow into two evaporator paths.
[0004] To permit the supply of several evaporator paths, U.S. Pat. No. 5,832,744 discloses a refrigeration system, in which the distributor comprises a valve between one refrigerant inlet and several refrigerant outlets, said valve being connected in series to a rotating turbine blade. The turbine blade is provided to ensure that the refrigerant is distributed evenly to all outlets of the distributor and thus also evenly to all evaporators.
[0005] In theory, such a distributor ensures an even distribution of the refrigerant to the individual evaporators. However, already small differences in the dimensions, which could, for example, occur during manufacturing, cause an uneven distribution of the refrigerant to the individual evaporators. Further, with such distributors, it is necessary that basically the individual distributors have the same thermal load and also the same flow resistance. If this is not the case, it may happen that one evaporator receives too much refrigerant, so that the refrigerant is not completely evaporated when it has passed the evaporator. Another evaporator, which is connected to the same distributor can receive too little refrigerant, so that the evaporator cannot deliver the desired refrigeration performance. The oversupply or the undersupply of the evaporator can in particular cause problems, if temperature sensors, which are located at the evaporators or in other positions in the refrigeration system, are controlling an expansion valve. Under unfavourable circumstances, the expansion valve will be caused to vibrate naturally, which further deteriorates the capacity and the efficiency of the refrigeration system.
SUMMARY OF THE INVENTION
[0006] The invention is based on the task of achieving a desired operation of the refrigeration system with simple means.
[0007] With a refrigeration system as mentioned in the introduction, this task is solved in that the distributor comprises a housing and a rotor rotatably supported in the housing, the circumference of the rotor having at least one radially directed projection, each interacting with one valve element of a valve.
[0008] In the following, the term “refrigeration system” is to be understood in a broad sense. It particularly comprises refrigeration systems, freezing systems, air-conditioning systems and heat pumps. The term “refrigeration system” has merely been chosen for reasons of simplicity. The evaporator paths can be arranged in different evaporators. For reasons of simplicity, the invention is explained in connection with several evaporators. However, the invention can also be used, if one evaporator has several evaporator paths, which can be controlled individually or in groups.
[0009] Thus, for each evaporator path the evaporator comprises a controllable valve that can be controlled by the radially directed projection of the rotor. Thus, it is possible to control the individual evaporator paths individually, that is, it is possible to supply each evaporator with the amount of refrigerant that is required. It no longer has to be considered that all evaporators have the same flow resistance. It is also of inferior importance, if the evaporators have to provide different refrigeration performances. An evaporator, from which a large refrigeration performance is required, receives correspondingly more refrigerant than an evaporator, which must supply less refrigeration. It must merely be ensured that during one rotation of the rotor the valve of the evaporator, which requires more refrigerant, remains open for a longer period than the valve of an evaporator that needs less refrigerant. As the rotor has a radially directed projection, it is sufficient if the rotor is supported to be sufficiently stable in the radial direction. All other supports can then be made in a relatively simple manner, as here the acting forces are small. It is also relatively easy to manufacture a radially directed projection, for example in the form of a cam. More than two evaporator paths can be provided with little effort.
[0010] Preferably, the valve elements are radially movable in relation to the rotation axis of the rotor. Thus, the effect of the radially directed projection can immediately be converted to a movement of the valve element. This simplifies the design of the distributor. When the valve elements are radially movable, more room is available for arranging the valve elements.
[0011] Preferably, each valve element has a return spring that presses the valve element in the direction of a valve seat. Without the influence of the cam or the radial projection on the rotor, the valve thus remains closed. Not until the projection acts upon the valve element, the valve element is lifted from the valve seat against the force of the return spring, thus opening the valve.
[0012] Preferably, the return spring is supported in a cage insert that is arranged in an outlet opening of the housing. On the one side, the cage insert is able to support the return spring so that it can act upon the valve element with the required closing force. On the other side, the cage insert also comprises one or more sufficiently large passage openings, so that the refrigerant flowing through a gap between the valve element and the valve seat can also flow through the cage insert into the corresponding outlet of the distributor.
[0013] Preferably, the cage insert has a guide opening for the valve element, in which a shaft of the valve element is guided. Thus, the cage insert does not only support the return spring, but also guides the valve element linearly, so that the valve element cannot, or can only to a permitted extent, tilt in relation to the valve seat. Thus, it is ensured that the valve can close tightly.
[0014] Preferably, the cage insert is arranged in the outlet opening by means of press fit. This permits a relatively simple manufacturing. The preassembled cage insert with return spring and valve element is simply pressed into the outlet opening of the housing. The frictional forces thus occurring will be sufficient to hold the cage insert in the housing. The forces acting upon the cage insert are relatively small anyway. When the valve element is open, they are made up of the force of the return spring and the pressure with which the refrigerant acts upon the valve element.
[0015] Preferably, a tappet is arranged between the rotor and each valve element. The tappet forms a transfer element between the rotor and the valve element. This makes it possible with a small rotor also to activate valves, when they are arranged on a larger radius. This gives the opportunity of providing a sufficient number of valves. Further, a larger design freedom is achieved.
[0016] It is preferred that the tappet has a length, which is smaller than a distance between the valve element bearing on the valve seat and the rotor outside the projection. Thus, with closed valve a play exists between the tappet and the rotor. Thus, it can be ensured that at any rate the valve will remain closed, when the tappet is not acted upon by the radial projection of the rotor. This play can be dimensioned so that in the total temperature area that is permitted for the distributor, it is ensured that the valves close safely.
[0017] Preferably, in a chamber that connects a distributor inlet to the valves, the housing has a circumferential projection through which the tappet is guided. In the circumferential direction the projection can also be interrupted, as long as it is ensured that for each valve a bore or a passage is available, through which the tappet is guided. Through the chamber the distribution of refrigerant to the individual valves is effected.
[0018] In an alternative or additional embodiment it may be provided that the tappet is held in a tappet locking ring. The tappet locking ring is inserted in the housing. When it is used together with the circumferential projection, it is ensured that the tappet is supported at two positions having a distance in the movement direction. Thus, it can also be ensured over time that the tappet and the valve elements always maintain a predetermined alignment to one another.
[0019] Preferably, the ends of the tappets facing the individual valve element have a diameter reduction. Thus, over the largest part of its length the tappet can be provided with a sufficiently large diameter, so that it can adopt the pressure forces which are transferred by the projection of the rotor to the individual valve element. When its end tapers, then it is able to penetrate so far through the opening on whose outside the valve seat is formed. Thus, it is possible to open the valves sufficiently to keep the flow resistance for the refrigerant small.
[0020] Preferably, each valve element is made with a cone shape. Thus, a sealing between the valve seat and the valve element can easily be achieved. Further, the valve element can be led somewhat through the opening at whose outside the valve seat is formed, so that it can easily be reached by the tappet.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In the following, the invention is described on the basis of a preferred embodiment in connection with the drawings, showing:
[0022] FIG. 1 is a schematic view of a refrigeration system with several evaporators,
[0023] FIG. 2 is a perspective top view of a distributor,
[0024] FIG. 3 is a top view of the distributor without motor,
[0025] FIG. 4 is an enlarged view of the rotor with projection,
[0026] FIG. 5 is a sectional view of a valve,
[0027] FIG. 6 is an enlarged section of FIG. 5 , and
[0028] FIG. 7 is a perspective view of a valve element in a cage insert.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] FIG. 1 is a schematic view of a refrigeration system 1 , in which a compressor 2 , a condenser 3 , a collector 4 , a distributor 5 and an evaporation arrangement 6 with several evaporators 7 a - 7 d arranged in parallel are joined to a circuit. The evaporator arrangement 6 can also comprise one single evaporator with several evaporation paths which are controlled individually or in groups. It is also possible to provide the evaporator arrangement 6 with several evaporators, of which at least one has several evaporator paths.
[0030] In a manner known per se, liquid refrigerant evaporates in the evaporators 7 a - 7 d , is compressed by the compressor 2 , liquefied in the condenser 3 and collected in the collector 4 . The distributor 5 is provided to distribute the liquid refrigerant to the individual evaporators 7 a - 7 d.
[0031] A temperature sensor 8 a - 8 d is arranged at the outlet of each evaporator 7 a - 7 d . The temperature sensor 8 a - 8 d determines the temperature of the refrigerant leaving the evaporator 7 a - 7 d . This temperature information is passed on to a control unit 9 that controls the distributor 5 in dependence of the temperature signals of the temperature sensors 8 a - 8 d.
[0032] The FIGS. 2 to 7 now show the distributor 5 in a partly schematic view. The distributor 5 comprises a drive motor 10 , for example in the form of a step motor. The drive motor 10 is fitted on a housing 11 that comprises an inlet that cannot be seen in FIG. 2 and several outlets 12 . The control unit 9 can be integrated in the motor 10 . However, it is also possible to arrange the control unit 9 separately from the motor 10 and merely supply the motor 10 with signals from the control unit 9 .
[0033] FIG. 3 shows a top view of the distributor 5 , the motor 10 having been removed, so that the inside of the distributor can be seen. As can be seen from FIG. 2 , the motor 10 at the same time serves as cover for the housing. Between the motor 10 and the housing 11 a sealing 13 is arranged, which prevents refrigerant from escaping from the housing 11 .
[0034] The motor 10 drives a rotor 14 , which is located in the housing 11 . The rotor 14 has a radial projection 15 , which has the shape of a cam with two bevelled sides 16 , 17 . When the rotor 14 rotates, the projection 15 acts upon a tappet 18 , steering it radially outwards. The tappets 18 are held in a tappet locking ring 19 . As appears from FIG. 5 , the housing 11 comprises a projection 20 that projects into a distributor chamber 21 . The tappets 18 are held once again in the projection 20 .
[0035] The distributor chamber 21 connects the inlet to the valves 22 , of which one is provided for each outlet 12 . With one projection 15 on the rotor 14 , one of the six valves 22 can be opened. The opening duration determines the amount of refrigerant that can flow off through the corresponding valve and thus through the corresponding outlet 12 .
[0036] All valves 22 have the same design. Each valve 22 comprises a valve element 23 that interacts with a valve seat 24 . The valve element 23 has a cone-shaped head 25 that is led through a housing wall 26 , on whose radial outside the valve seat 24 is arranged.
[0037] The valve element 23 with its head 25 is pressed in the direction of the valve seat 24 by the force of a return spring 27 . The return spring 27 engages the radial outside of the head 25 . From here also a shaft 28 of the valve element 23 extends radially outwards. The shaft has a smaller diameter than the head 25 , so that the return spring 27 has a sufficient bearing surface.
[0038] The other end of the return spring 27 is supported on a cage insert 29 that is pressed into an outlet opening 30 . Thus, the cage insert 29 is fitted in the housing 11 by means of a press fit. As can be seen from FIG. 7 , the cage insert 29 has several legs 31 , with which it is held in the housing 11 . Between them there are spaces through which refrigerant can flow into the corresponding outlet 12 when the valve 22 is open, that is, the valve element 23 is lifted from the valve seat 24 .
[0039] The cage insert 29 comprises a guide opening 34 for guiding the shaft 28 of the valve element 23 so that the valve element 23 is sufficiently protected against a tilting. Thus, an edging of the valve element 23 in relation to the valve seat 24 is prevented, if it exceeds a predetermined measure.
[0040] The tappets 18 are shorter than a distance between the valve element 23 and the rotor 14 in the area outside the radial projection 15 . This results in a certain play between the rotor 14 and the tappet 18 , which interacts with a closed valve, or between the tappet 18 and the valve element 23 . Thus, it can easily be ensured that the valve 22 is closed, if the projection 15 at the rotor 14 is not exactly meant to open that corresponding valve 22 .
[0041] The end of the tappet 18 interacting with the valve element 23 comprises a diameter reduction 32 . Thus, on the one side it can be ensured that the tappet 18 has a sufficient cross-section to adopt the pressure forces exerted by the projection 15 without a deformation. On the other side, the area in which the tappet 18 interacts with the valve element 23 is thin enough to pass through the opening 33 in the wall 26 of the housing at whose radial outside the valve seat 24 is arranged. Thus, it can be ensured that, when the tappet 18 with its diameter reduction 32 extends into the opening 33 , a sufficient flow cross-section for the refrigerant through the valve 22 in question is provided.
[0042] While the present invention has been illustrated and described with respect to a particular embodiment thereof, it should be appreciated by those of ordinary skill in the art that various modifications to this invention may be made without departing from the spirit and scope of the present. | The invention relates to a refrigeration system comprising a refrigerant circuit provided with a plurality of evaporator paths and a distributor ( 5 ) for distributing refrigerants to the evaporator paths, said distributor comprising a controllable valve ( 14 ) for each evaporator path. The aim of the invention is to enable the refrigeration system to be operated as desired using simple means. To this end, the distributor ( 5 ) comprises a housing ( 11 ) and a rotor which is rotatably mounted in the housing ( 11 ) and comprises at least one radially oriented projection ( 15 ) on the circumference thereof, which interacts respectively with a valve element of a valve. | 5 |
This application is a divisional of application Ser. No. 11/269,838, filed on Nov. 9, 2005 now U.S. Pat. No. 7,621,012, which claims the benefit of the Patent Korean Application No. P2004-091991, filed on Nov. 11, 2005, which is hereby incorporated by reference as if fully set forth herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a controller effectively controlling the power for a washing machine or a drier, and a method of doing the same, and more particularly, to a controller for a washing machine or a dryer, and a method for supplying the power so that a washing machine and a drier as a one body may perform an optimal efficiency in a range of a current limit, when supplied the power by the same power source.
2. Discussion of the Related Art
FIG. 1 is a diagram illustrating a related art device combining a washing machine and a dryer.
As sown in FIG. 1 , a washing machine 10 and a dryer 20 are included. At a top of the washing machine 10 are formed a display part 11 for displaying operation of the washing machine and an opening part 12 for having the laundry loaded therein or vice versa. At a top of the dryer are formed a display part 21 for displaying operation of the dryer 20 and an opening part 22 for having the laundry loaded therein or vice versa.
In general, every electric home appliance has an optimal performance current for performing the optimal efficiency. There are some cases of not supplying an optimal performance current due to other reasons, and that is caused by a current limit.
The current limit is an electric current value limited for securing the customer, preventing a fire caused by overheating an electric home appliance, and an accident of an electric shock caused by electric leakage due to overflowing currents in the electric home appliances. A designer of an electric home appliance should set an optimal performance current in a range of a current limit value. Especially, the sum total of the whole currents for an electric home appliance combining more than two products should not exceed the current limit, even in case that the more than two machines are put into operation at the same time.
For example, under the regulations a current limit of an average American house should not exceed 15 amps (A), and in that case, the sum total of a current consumption for the electric home appliance should not exceed 15 amps.
For example, when designing a device combining a washing machine and a dryer, the current consumption in case of putting the washing machine and the dryer into operation at the same time should meet the current limit. Thus, each electric home appliance has an optimal performance current, and since the security of the customers has to be put into consideration, the device should be designed to find an optimum level between its optimal performance current and the current limit and to perform the optimal efficiency within the range.
Generally, the optimal performance current is determined by independent operation of each product. If more than two products are operated at the same time and the current value satisfying each optimal performance current of the products is provided, the current value would exceed the current limits of the products. Also, even in case that each product is not operated at the same time to satisfy the current limit values of each product, an amount of currents is reduced in advance, preparing against the case of operating the products simultaneously. Thereby permanent current loss may be cased as shown in FIG. 2 .
Referring to FIG. 2 , a method of supplying the power for the related art washing machine and dryer will be described.
A product 1 (a washing machine) and a product 2 (a dryer) drive by means of lower currents 32 and 42 than each optimal performance current thereof 33 and 43 , even when the product 1 and 2 are operated separately. That is, even when either of the two products is operated, the two products are designed to drive by the regularly lower currents 32 and 42 than the optimal performance currents 33 and 43 for being prepared against the case of operating the two products simultaneously. Thus, the following problem may be caused. Since the current loss 31 and 41 of the products are expected in advance, neither of the two products may perform its optimal efficiency although either of the products is operated.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a controller effectively controlling the power for a washing machine or a dryer, and a method for doing the same.
An object of the present invention is to provide a method of controlling the power for a washing machine or a dryer to be operated at an optimal performance in a range satisfying a current limit.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a controller for a washing machine comprising a micom wherein an optimal performance current value for the washing machine and an electric current limit for concurrent operation of the washing machine and a dryer are set therein; and communication means for communicating with a controller of the dryer, wherein the micom determines through the communication with the dryer the electric current value to be supplied to the washing machine according to an operation state of the dryer.
The micom determines the electric current value to be supplied to the washing machine as the optimal performance current value of the washing machine, once a motor for driving a drum of the dryer is judged not to be operated.
Also, the micom determines the electric current value to be supplied to the washing machine, corresponding to a ratio of between the optimal performance current values of the dryer and the washing machine, once the motor for driving the drum of the dryer is judged to be operated.
Alternatively, the micom determines the electric current value to be supplied to the washing machine as one of the optimal performance current value of the washing machine and the electric current value given after subtracting the optimal performance current value of the dryer from the current limit value, once the motor for driving the drum of the dryer is judged to be operated. As described above, the determination may be made by setting it in the micom in advance, or by inputting it outside, for example, an input button or determination means such as an auxiliary home network.
In another aspect of the present invention, a controller for a dryer comprising a micom wherein an optimal performance current value for the dryer and an electric current limit for concurrent operation of the washing machine and the dryer are set therein; and communication means for communicating with the controller of the washing machine. The micom determines through the communication with the washing machine the electric current value to be supplied to the dryer according to an operation state of the washing machine.
Just like in the controller of the washing machine, the micom of the controller for the dryer determines the electric current value to be supplied to the dryer as the optimal performance current value of the dryer, once a motor for driving the drum of the washing machine is judged not to be operated.
Also, the micom determines the electric current value to be supplied to the dryer out of the electric current limit, corresponding to a ratio of the optimal performance current values between the dryer and the washing machine, once the motor for driving the drum of the washing machine is judged to be operated.
Alternatively, the micom determines the electric current value to be supplied to the dryer as one of the optimal performance current value of the dryer and the electric current value given after subtracting the optimal performance current value of the washing machine from the current limit value, once the motor for driving the drum of the washing machine is judged to be operated. The determination may be made by setting it in the micom in advance, or by inputting it outside as described above in the controller of the washing machine.
On the other hand, a method of controlling the power for a washing machine or a dryer comprising a first step; a second step; and a third step. The first step is for setting in the micom each optimal performance current value of the washing machine and the dryer, and a current limit value for the washing machine and the dryer to be operated safely when operating the washing machine and the dryer simultaneously. Hence, the second step is for exchanging and communicating operation information of the washing machine and the dryer by using a communication port connected to each micom of the washing machine and the dryer. The third step is for of supplying currents to the washing machine and the dryer in a range of the current limit according to the operation information.
In the third step, in case only the washing machine is operated, the washing machine is supplied its optimal performance current value. In case only the dryer is operated, the dryer is supplied its optimal performance current value. Then, in case the washing machine and the dryer are operated simultaneously, the current value is divided and supplied to each of the washing machine and the dryer.
In the third step, in case the currents are divided and supplied to each of the washing machine and the dryer, the current limit value is divided by a ratio of each optimal performance current value of the washing machine and the dryer.
Furthermore, a priority setting step of setting priority is further comprised between the first and second step. Thus, in case the washing machine and the dryer are operated simultaneously in the third step, one of the washing machine and the dryer chosen by the priority in the priority setting step is supplied its optimal performance current, and the other product is supplied the currents given after subtracting the optimal performance current value from the current limit value.
In the priority setting step, the priority may be set through a home server of a home network system.
On the other hand, the communication means according to the present invention is employed for communicating if the driving part of the washing machine and the dryer is operated or not. But, the communication means may communicate data more than that.
One example for the washing machine and the dryer to communicating each other will be described. The one product sends an electric signal through a communication cable for allowing the other product to know if a motor of the one product is switched on. Hence, the other product receives the signal to judge of the motor of the one product is operated, and then determines which current value to use.
According to the present invention, in case that one of the products is operated, or the products are operated at the same time, the currents are supplied for performing the optimal efficiency, thereby preventing the permanent current loss. Also, accidents caused by over-supplying currents are prevented, and the security of the customers is kept.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
FIG. 1 is a diagram illustrating a configuration of a device combining a conventional washing machine and dryer.
FIG. 2 is a graph illustrating a method of controlling the power for a related art washing machine and dryer.
FIG. 3 is a graph of a current when only a washing machine is operated by a method of controlling the power for a washing machine and a dryer according to the present.
FIG. 4 is a diagram schematically illustrating the method of controlling the power for the washing machine and the dryer according to the present invention.
FIG. 5 is a flow chart illustrating the method of controlling the power for the washing machine and the dryer according to the present invention.
FIG. 6 is a flow chart illustrating another method of supplying the power for the washing machine and the dryer according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
FIG. 4 is a diagram schematically showing that each controller of a washing machine and a dryer controls the power of the washing machine and the dryer. The controller includes a micom and communication means.
As shown in FIG. 4 , the washing machine 100 includes a micom 110 , a communication port 120 connected to the micom for communicating with the dryer 200 , and a power supply unit 130 for supplying the power to the washing machine.
Also, the dryer 200 includes a micom 210 , a communication port 220 connected to the micom for communicating with the washing machine 100 , and a power supply unit 130 for supplying the power to the dryer 200 .
The communication port 120 of the washing machine and the communication port 220 of the dryer are connected by a communication cable to exchange and communicate operation information each other. The power supply units 130 and the 230 are operated to supply the power needed for each of the washing machine and the dryer by means of the control of each micom 110 and 210 .
First of all, each optimal performance current value for the washing machine and the dryer, and a current limit value are set in the each micom 110 and 210 . Each optimal performance current value is for the washing machine and the dryer to perform the optimal efficiency, and the current limit value is a maximum vale of currents to use the two products safely when the two products are operated simultaneously.
The micoms 110 and 210 divide the currents supplied to the washing machine and the dryer for performing an optimal efficiency within a range of the current limit, and instruct to supply the currents to the washing machine and the dryer. The micoms 110 and 210 check through the communication ports 120 and 220 in advance whether the washing machine and the dryer are required to be operated or not. If only the washing machine is required to be operated, the micoms 110 instructs the power supply unit 130 to supply the washing machine its optimal performance current. Whereas, if only the dryer is required to be operated, the micom 210 instructs the power supply unit 130 to supply the dryer its optimal performance current. If both of the washing machine and the dryer are required to be operated simultaneously, the micoms 110 and 210 instruct the power supply units 130 and 230 of the washing machine and the dryer to supply the currents that remains after dividing the current limit by each optimal performance current ratio of the washing machine and the dryer to each of the washing machine and the dryer.
Referring to FIG. 3 , a case will be described that a product 1 (the washing machine) is operated and a product 2 (the dryer) is not operated.
Once it is judged that the washing machine is required to be operated and the dryer is not, the washing machine is supplied its optimal performance current value 61 .
That is, since the micoms of the products 1 and 2 check the interaction of the products 1 and 2 , and supply each optimal performance current of the two products, the permanent current loss 31 and 41 shown in FIG. 2 may not be created. Although the currents are supplied in that way, the currents may not exceed the current limit 63 , thereby possible to supply the currents safely and efficiently.
Also, auxiliary control means may be provided outside of the washing machine and the dryer as necessary. The auxiliary control means gives the priority to the washing machine or the dryer, and allows either of the two products 1 and 2 operated by its optimal performance current. Alternatively, the priority may be set in advance in each micom of the products 1 and 2 . Alternatively, an input button may be provided for a user to input the priority directly.
FIG. 4 shows a case that the control means is provided by using a home network system. The home network system is a system that controls and manages electric home appliances such as a washing machine, a refrigerator, a television, a VCR, an electric heater, and a lightning unit in a building by using a communication unit such as a mobile phone, and a public phone outside the building after connecting the electric home appliances with a cable or wirelessly.
The home network system requires a home server 300 connected with an outside communication network, for example a refrigerator, for controlling the electric home appliances connected with a home network system and exchanging information. A micom 310 provided in the home server 300 is connected to the micoms 110 and 210 of the washing machine and the dryer in a home network system. The micom 310 also controls the power supply of the two products 1 and 2 according to the present invention.
More specifically, the user inputs the priority into the micom 310 of the home server 300 , and then it is determined by the inputted priority which of the washing machine and the dryer is put into operation in its optimal efficiency. In case that the washing machine and the dryer are operated simultaneously, the priority is applied. In that case, the micoms 110 and 210 instruct the power supply unit of the product 1 or 2 determined by the priority to supply its optimal performance current to the product determined by the priority inputted in the micom 310 of the home sever 300 . Hence, the micoms 110 and 210 also instruct the power supply unit of the other product 1 or 2 to supply the remaining currents except the optimal performance current to the other product 1 or 2 . Thus, the optimal performance current may be supplied to the one product determined prior to the other product.
Next, referring to FIG. 5 , a method of a power supply for a washing machine and a dryer according to the present invention will be described.
First, the method includes a first step (S 1 ) in which a current limit value and each optimal performance current of the washing machine and a dryer are set in micoms each provided in the washing machine and the dryer. The current limit value is a maximum value used in the two products 1 and 2 when the two products 1 and 2 are operated simultaneously, and a value set for the two products to be operated safely. Also, each optimal performance current is a current value designed for each product to perform its optimal efficiency. Each optimal performance current value should be in a range of the current limit value.
Next, a second step (S 2 ) is included in which operation information of the washing machine and the dryer is exchanged and communicated by using communication ports connected each other provided in each micom. The operation information is a signal showing whether the washing machine or the dryer is operated or not.
Next, a third step is included in that currents are supplied in a range of the current limit according to operation information of the washing machine and the dryer.
In the third step, the currents are supplied as follows. First, it is checked if the washing machine is required to be operated (S 3 ). Then, it is checked if the dryer is required to be operated in case that the washing machine is not required to be operated (S 4 ). In case the dryer is required to be operated, the optimal performance current of the dryer is supplied to the dryer (S 5 ).
In the S 3 step, in case that the washing machine is required to be operated, it is checked again if the dryer is required to be operated (S 6 ). Judged that the dryer is not required to be operated, the optimal performance current of the washing machine is supplied to the washing machine (S 7 ).
In case that the washing machine and the dryer are all required to be operated, after dividing the current limit by each optimal performance current value of the washing machine and the dryer, the given currents are supplied to each of the washing machine and the dryer (S 8 ).
As shown in FIG. 6 , the user may put more emphasis on either of the washing machine and the dryer as necessary, in case that the two products are operated simultaneously. For that, a priority setting step (S 12 ) may be further included between a step (S 11 ) of FIG. 6 corresponding to the step 1 of FIG. 5 and a step (S 13 ) of FIG. 6 corresponding to the step S 2 of FIG. 5 . In the step (S 12 ), auxiliary control means may be further provided in the washing machine and the dryer for setting the priority. The control means may use the micom in the home server of the home network system for controlling.
When the washing machine and the dryer are operated simultaneously, according to the priority, either of the two products is supplied its optimal performance current. Hence, the other product is supplied the currents given after subtracting its optimal performance from the current limit value (S 19 ).
The method of controlling the power for the washing machine and the dryer according to the present invention may be applied by using a communication module connecting the micoms of the washing machine and the dryer each other, in case that the power is supplied by the same current source after connecting a conventional washing machine and a conventional dryer.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. | The present invention relates to a controller effectively controlling the power for a washing machine and a drier, and a method of doing the same. More particularly, it relates to a controller for a washing machine or a dryer, and a method for supplying the power so that a washing machine and a drier as a one body may perform an optimal efficiency in a range of a current limit, when supplied the power by the same power source. A controller for a washing machine comprising a micom; and communication means for communicating with a controller of a dryer. A controller for a dryer comprising a micom; and communication means for communicating with the controller of the washing machine. | 3 |
FIELD OF THE INVENTION
[0001] The invention relates to standard control reference materials for use in cytokine and in cell proliferation assays. The invention also relates to methods for producing such materials.
BACKGROUND AND PRIOR ART KNOWN TO THE APPLICANT
[0002] The detection of cytokine release by ELISPOT assay and the quantification and identification of intracellular cytokines by flow cytometry are both widely used as indices of cell mediated immune responses. In the so-called ELISPOT assay, cytokines released from immobilised cells typically interact with an immunoassay, such as an ELISA assay, to produce a coloured “spot” on the assay plate providing both qualitative (e.g. type of immune protein) and quantitative (number or proportion of cells responding) information. The standardisation of these assays requires the development of reliable reference standards for monitoring intracellular cytokine levels and cytokine release in test samples, thus allowing comparability between different laboratories and assays.
[0003] Stimulated (cytokine positive), fixed, cryopreserved cells are available commercially for intracellular flow cytometry (Becton Dickinson, Oxford, UK), and freeze dried unstimulated cells are available either as controls for surface staining or for purposes of haematology analysis (Beckman Coulter UK Ltd, High Wycombe, UK).
[0004] For ELISPOT assays, or other assays where cytokine release from cells is monitored, only cryopreserved live cells from individual donors are currently available.
[0005] The presently-available approaches to the provision of a standardised reference material have a number of drawbacks: In order to standardise reference materials over a large number of laboratories world-wide, and to provide reference materials that may be used over many years, a large amount of stable material is required. However, live cells from multiple donors cannot be pooled to make large single batches due to mixed lymphocyte reactions, resulting in cell death and over-expression of cytokines
[0006] Cryopreserved cells also require specialised storage using e.g. liquid nitrogen and shipment on dry ice, thus increasing costs. There is also the risk of thawing and refreezing during shipment, in the event of power failure to refrigeration devices, say, leading to deterioration of the material, so rendering it useless as a reference standard. Furthermore, cyropreserved cells must be carefully thawed to ensure consistency of responses. It has proven difficult to obtain consistent results between laboratories using this approach.
[0007] Measurement of cell proliferation in mammalian cells is also an important technique for e.g. the assessment of the effects of exogenous agents on a cell's ability or propensity to divide. For example, such assays may be used for detecting the marked proliferation of cells of the immune system following an immune response. A number of techniques are currently used wherein cells are labeled with a detectable marker that is shared between daughter cells following cell division.
[0008] One such technique uses the fluorescent dye carboxyfluorescein diacetate succinimidyl ester (CFSE or CFDA, SE). The technique is described by Lyons, B. in Immunol. Cell Biol 1999; 77(6):509-515 in which the author reports that “The technique can be used both in vitro and in vivo, allowing eight to 10 successive divisions to be resolved by flow cytometry. Furthermore, viable cells from defined generation numbers can be sorted by flow cytometry for functional analysis”. Other techniques include the incorporation of bromodeoxyuridine or tritiated thymidine into the cells.
[0009] Whilst these assays are well known, a difficulty that arises is the provision of reference standards for cross-calibration and quality control when the assays are used across different analysis laboratories, or are used successively over long periods of time, e.g. during clinical longitudinal studies.
[0010] The lack of suitable reference materials for such cytokine and cell proliferation assays hinders robust testing methodologies, especially in respect of comparability between different laboratories and assays. It is amongst the objects of the present invention to attempt a solution to these problems.
SUMMARY OF THE INVENTION
[0011] Accordingly, in a first aspect, the invention provides a method of preparing cellular reference material comprising the steps of: (a) obtaining a cell sample, isolated from a human or animal body, said cell sample comprising cells selected from the group comprising: basophils, neutrophils, eosinophils, monoctytes, lymphocytes (B-lymphocytes and T-lymphocytes) and natural killer cells (all peripheral blood mononuclear cells, PBMC), thrombocytes and cell lines; (b) stimulating said cells to produce cytokines in the presence of a cytokine secretion inhibitor; (c) fixing said stimulated cells by addition of a fixative; (d) preserving said fixed stimulated cells by freeze drying.
[0012] By cell lines, we mean a cell culture capable of proliferation given appropriate fresh media and space, such cells being originally isolated from a human or animal body, and capable of cytokine production. Such cells may either produce cytokines inherently, or may be modified to include exogenous genetic material coding for, and leading to synthesis of, one or more cytokines, e.g. including but not restricted to TNF-α, IFN-γ, IL-1 and IL-6. Exogenous DNA may be introduced into a recipient eukaryote cell by, say, micro-injection, electroporation, the use of calcium phosphate or a liposomal transfection reagent, and said genetic material may be subsequently integrated into the chromosomal DNA of said cells, or may remain present as e.g. a plasmid. For cells that are capable of producing cytokines inherently, such cells may be modified, e.g. by the introduction of promoter sequences to upregulate cytokine production. Cells may be stimulated if required, e.g. by use of a mitogen, to produce cytokines and preserved according to the technique(s) described herein.
[0013] Transduction of a cytokine gene into neoplastic cells is known to elicit a strong inflammatory host reaction (see e.g. “The boosting effect of co-transduction with cytokine genes on cancer vaccine therapy using genetically modified dendritic cells expressing tumor-associated antigen”, International journal of oncology; OJIMA Toshiyasu et al: ISSN 1019-6439 2006, vol. 28, no4, pp. 947-953). In vivo, this impairs tumour growth. In vitro, intra-cellular cytokines may be preserved according to the technique(s) described herein.
[0014] Such cell lines may include cell lines derived from basophils, neutrophils, eosinophils, monoctytes, lymphocytes (B-lymphocytes and T-lymphocytes), natural killer cells (all peripheral blood mononuclear cells, PBMC) and thrombocytes, or cell lines such as HeLa, HL-60, A-549, Jurkat, LNCap and CAPAN-1 cells.
[0015] In preferred embodiments, the invention provides a method of preparing cellular reference material comprising the steps of: (a) obtaining a cell sample, isolated from a human or animal body, said cell sample comprising cells selected from the group comprising: basophils, neutrophils, eosinophils, monoctytes, lymphocytes (B-lymphocytes and T-lymphocytes) and natural killer cells (all peripheral blood mononuclear cells, PBMC), and thrombocytes; (b) stimulating said cells to produce cytokines in the presence of a cytokine secretion inhibitor; (c) fixing said stimulated cells by addition of a fixative; (d) preserving said fixed stimulated cells by freeze drying.
[0016] In a second independent aspect, the invention also provides a method of preparing cellular reference material comprising the steps of: (i) obtaining a mixed cell population, isolated from a human or animal body, said mixed cell population comprising a plurality of cell types selected from the group comprising: peripheral blood mononuclear cells; thrombocytes; (ii) fractionating said mixed cell population to produce a plurality of fractions having distinct populations of cell types within each fraction; (iii) stimulating cells within one or more of said fractions to produce cytokines in the presence of a cytokine secretion inhibitor; (iv) fixing said cells within each fraction by addition of a fixative; (v) recombining a plurality of said fractions to produce a mixture of differentially-stimulated cells; (vi) preserving said mixture of differentially-stimulated cells by freeze-drying or cryopreservation.
[0017] In this way, reference standards mimicking a particular pattern of cytokine expression in different cell types may be produced. Such cytokine expression standards would provide a benefit in both the clinical and research setting by assisting in both the diagnosis/prognosis of potential disease states and in the analysis of material/experimental outcomes within the research laboratory/empirical setting.
[0018] In either aspect of the invention it is preferred that said cell sample is isolated from a mammalian body, and more preferably from a human body.
[0019] Also in any aspect of the invention, it is preferred that said cells are stimulated by the addition of a mitogen. Preferably, and in particular for intracellular cytokine staining, said mitogen comprises PMA (phorbol-12-myristate-13-acetate). Preferably also, said mitogen comprises Ionomycin. More preferably, said mitogen comprises a mixture of PMA (phorbol-12-myristate-13-acetate) and Ionomycin. Preferably also, and in particular for use in Elispot assays, said mitogen comprises a mixture of PHA (Phyto-hemagglutinin), IL-2 (interleukin-2) and co-stimulatory anti-human CD28 monoclonal antibody.
[0020] Also in any aspect of the invention it is preferred that said cytokine secretion inhibitor comprises Brefeldin A.
[0021] Also in any aspect of the invention it is preferred that said fixative comprises paraformaldehyde. Preferably, said fixative comprises a mixture of paraformaldehyde and chromium chloride. Fixation has the benefit of suspending intra- and extra-cellular biological activity, including apoptosis, thus improving the biological and structural integrity of the cells during the freeze-drying process.
[0022] Also in any aspect of the invention the method further comprises the step of removing residual fixative after fixing said cells and before preserving said cells. This allows cells to be used immediately upon reconstitution without additional washing step to remove fixatives. One benefit of this step is that it minimises volumetric variation of cell numbers. Excess fixative can cause non-specific staining and prevent the release of cytokines in ELISPOT assays.
[0023] Also in any aspect of the invention the method further comprises the step of exposing said fixed cells to hypertonic conditions prior to preserving said cells. By processing the cells in their hypohydrated state, the cells become physically more resilient and thus strengthened—the overall yield of reference material is increased.
[0024] Also in any aspect of the invention the method further comprises the step of adding a cryoprotectant to said fixed cells prior to freeze-drying said cells. The addition of a cryoprotectant has the benefit of improving the structural integrity of the cells during the freeze-drying process.
[0025] Overall, among the benefits provided by the present invention are that:
[0026] (i) although the reference cells so produced are optimally stable at +4° C., the cells can be shipped at ambient temperature without degradation;
[0027] (ii) the cells are easily reconstituted with distilled water;
[0028] (iii) the cells function both in flow cytometry assays, and also in ELISPOT assays, the cells releasing their cytokines to the surrounding environment, particularly when held at an elevated temperature, around 37° C.
[0029] Also included in the scope of the invention is a method of preparing cellular reference material comprising the steps of: obtaining a plurality of cell samples isolated from a plurality of individuals; carrying out a method described above on each cell sample; and further comprising the step of combining fixed cells derived from a plurality of said samples prior to preserving said cells. This has the added benefit of allowing large batches from pooled donors to be prepared and stored, since the methods described herein obviate any mixed lymphocyte reactions which would otherwise result from pooling live cells. Thus, large quantities of standardized reference material may be produce, which has hitherto not been possible.
[0030] Also included in the scope of the invention is a method of preparing cellular reference material comprising the steps of: obtaining a plurality of mixed cell populations isolated from a plurality of individuals; carrying out a method described above, according to the second aspect of the invention, on each mixed cell population; and further comprising the step of combining fixed cells derived from a plurality of said mixed cell populations prior to preserving said cells. This has the added benefit of allowing the synthesis/production of mixed lymphocyte populations which both quantitively and qualitatively mimic the mixed lymphocyte populations found in various disease states. For example, with the onset of Graves disease, thyrocytes express cytokines they normally would not, such as TNF-α, IFN-γ, IL-1 and IL-6.
[0031] Also included in the scope of the invention is a method of preparing cellular reference material comprising the steps of: preparing unstimulated fixed cells according to the method steps of any preceding aspect in which the stimulation step (b) or (iii) is omitted; combining said unstimulated fixed cells with stimulated fixed cells prepared according to the method steps of any preceding aspect; and preserving said combined cells by freeze drying or cryopreservation. This has the added benefit of providing mixed lymphocyte populations which mimic the non-diseased state as a comparator for disease-state populations, i.e. to act as a negative control.
[0032] In a further independent aspect, the invention also provides a method of preparing cellular reference material comprising the steps of: (i) obtaining a mixed cell population, isolated from a human or animal body, said mixed cell population comprising a plurality of cell types selected from the group comprising: peripheral blood mononuclear cells; thrombocytes; (ii) fractionating said mixed cell population to produce a fraction having predominantly a single cell type within said fraction; (iii) labeling cells within said fraction; (iv) fixing the labeled cells within said fraction by addition of a fixative; and (v) preserving said labeled cells by freeze-drying.
[0033] For example, CD4 + cells may be isolated from PBMC using immuno-magnetic sorting, stained with an anti-CD4 antibody labeled with FITC (fluorescein isothiocyanate) and freeze-dried following fixation as described herein. Such cells may be used as reference standard for e.g. fluorescence calibration of flow cytometry apparatus.
[0034] In a further aspect, the invention provides a method of preparing cellular reference material comprising the steps of: (a) obtaining proliferation-competent mammalian cells, isolated from a human or animal body; (b) labeling said cells with a label that is divided between daughter cells during cell proliferation; (c) stimulating said labeled cells to proliferate; (d) allowing said cells to proliferate; (d) fixing said proliferated cells by addition of a fixative; and (e) preserving the resultant cells by freeze drying or cryopreservation.
[0035] Preferably, said cells are preserved by freeze-drying. Although useful, cryopreserved cells require specialised storage using e.g. liquid nitrogen and shipment on dry ice, thus increasing costs. There is also the risk of thawing and re-freezing during shipment, in the event of power failure to refrigeration devices, say, leading to deterioration of the material, so rendering it useless as a reference standard. Furthermore, cyropreserved cells must be carefully thawed to ensure consistency of responses. Freeze-drying therefore provides considerably more stable reference materials. Fixation of the cells has the benefit of suspending intra- and extra-cellular biological activity, including apoptosis, thus improving the biological and structural integrity of the cells during the freeze-drying process.
[0036] Preferably, said cells are isolated from a mammalian body, and more preferably said cells are isolated from a human body.
[0037] In any aspect of the invention where said cells comprise proliferation-competent mammalian cells, it is preferred that said cells are stimulated by the addition of a mitogen. Preferably, said mitogen comprises PMA (phorbol-12-myristate-13-acetate). Preferably also, said mitogen comprises Ionomycin. More preferably, said mitogen comprises a mixture of PMA (phorbol-12-myristate-13-acetate) and Ionomycin. In alternative embodiments, stimulation of proliferation may be carried out by addition of a mitogenic monoclonal antibody such as UCHT1.
[0038] Also in any aspect of the invention where said cells comprise proliferation-competent mammalian cells, it is preferred that said fixative comprises paraformaldehyde. More preferably, said fixative comprises a mixture of paraformaldehyde and chromium chloride.
[0039] Also in any aspect of the invention where said cells comprise proliferation-competent mammalian cells, it is preferred that the method further comprises the step of removing residual fixative after fixing said cells and before preserving said cells. This allows cells to be used immediately upon reconstitution, or thawing, without an additional washing step to remove fixatives. A benefit of this stage is that it volumetric variation of cell numbers. Excess fixative can cause non-specific staining of the cell suspension.
[0040] Also in any aspect of the invention where said cells comprise proliferation-competent mammalian cells, it is preferred that the method further comprises the step of exposing said fixed cells to hypertonic conditions prior to preserving said cells. By processing the cells in their hypohydrated state, the cells become physically more resilient and thus strengthened—the overall yield of reference material is increased.
[0041] Also in any aspect of the invention where said cells comprise proliferation-competent mammalian cells, it is preferred that the method further comprises the step of adding a cryoprotectant to said fixed cells prior to preserving said cells. The addition of a cryoprotectant has the benefit of improving the structural integrity of the cells during the freeze-drying or cryopreservation process.
[0042] Also in any aspect of the invention where said cells comprise proliferation-competent mammalian cells, it is preferred that said cells are labeled with a fluorescent label. More preferably, said fluorescent label comprises CFSE (carboxyfluorescein succinimudyl ester).
[0043] Also included within the scope of the invention is a method of preparing cellular reference material substantially as described herein.
DESCRIPTION OF PREFERRED EMBODIMENTS
Example 1
Production of Stimulated Cell Standards
[0044] In one embodiment of the invention, “buffy coats” are obtained e.g from phlebotomised donors or a national blood collection agency. The buffy coat fraction of blood is that portion of blood that, following centrifugation, contains the majority of the white blood cells and platelets. All such obtained buffy coats will typically be tested to ensure they are negative for Treponema pallidum haem-agglutination test (“TPHA”), Hepatitis B surface antigent (“HBsAg”), anti Human Immunodeficiency Virus 1 (“anti-HIV1”), anti-Human Immunodeficiency Virus 2 (“anti-HIV 2”) and anti Hepatitis C Virus (“anti-HCV”) prior to use.
[0045] Residual erythrocytes contained within the buffy coats are removed by application of any standard, commercially available lymphocyte density gradient preparation, such as Lymphoprep, and peripheral blood mononuclear cells (“PBMC”) are subsequently isolated/collected, again by application of a lymphocyte density gradient preparation. The PBMC are then washed in a mammalian cell culture medium such as RPMI 1640 media.
[0046] For production of stimulated reference standards (as opposed to an unstimulated, negative control standard) the PMBC are immuno-stimulated using T-cell stimulating mitogens, typically within an environment containing 4 - 6 % carbon dioxide, and at a temperature of 36 - 38 ° C. In preferred embodiments, a combination of immuno-stimulants are used, said stimulants commonly comprising phorbol 12 -myristate 13 -acetate (PMA) (applied at a concentration of 0.01-0.03 μg per ml, say 0.02 μg per ml) and Ionomycin (applied at a concentration of 0.125-0.165 μg per mg, say 0.145 μg per mg). The stimulation technique is suitable for cytokine-production, and if immuno-stimulated for 4-6 hours, cytokine production within the cells PMBC is detectable.
[0047] The PMBC are simultaneously combined with a commercially available extra-cellular protein transport inhibitor, such as Brefeldin A or Monensin, which results in cytokine accumulation within the said PMBC. If Brefeldin A is used, it would commonly be applied at a concentration of 9.0-11.0 μg per ml, say 10 μg per ml.
[0048] Following stimulation, the PBMC are washed in a combination of foetal calf serum (“FCS”) and phosphate buffered saline (“PBS”), the FCS being used typically at a concentration of 9-12% v/v, say 10% and the PBS typically being double strength.
[0049] The washed PBMS are then re-suspended in a buffered culture medium (again comprising double strength PBS and 9-12% FCS), with the addition of 0.1-20% (v/v) of a commercially available transport fixative containing a combination of paraformaldehyde (0.1-0.2% w/v) and chromium chloride (0.5% w/v) in 0.85% (w/v) PBS. An example of one such fixative is known by the trade name “TransFix”. The buffered culture medium and fixative is applied to the said PBMC at a rate of 8×10 6 PBMC per ml.
[0050] For production of unstimulated, negative control cells, PBMC are fixed immediately following isolation in paraformaldehyde and chromium chloride, as described above, and stored until required at +4° C.
[0051] Following stimulation and fixing (or just fixing, for negative control standards), the PBMC are subsequently washed with chilled (+4° C.) freeze drying buffer (a cryoprotectant). A typical buffer would comprise a double volume of 10% protein, typically, foetal calf serum or albumin in double strength PBS. The use of a freeze drying buffer improves PBS stability during the subsequent freeze drying process. These cells may then be stored at chill temperatures (typically +4° C.) before freeze-drying. In order to optimise the quality and consistency of the reference standards, the shelves of a freeze dryer are pre-cooled in order to maintain a temperature of +4° C. during the loading process.
[0052] After fixing, cells from a plurality of donors may be mixed together to increase the total volume of reference material so produced. The process of fixing allows cells from different donors to be mixed together without causing lymphocyte cross-reactions. Furthermore, fixed stimulated cells may be mixed with fixed, unstimulated cells (which can also be used as negative controls) in order to produce a cell population demonstrating typical levels of cytokine stimulation or for a minimum potency positive control.
[0053] The stimulated (or unstimulated), fixed cells are loaded into aliquots/capped vials. A filling machine such as one sold under the trade name Paxal, is suitable for large scale aliquoting.
[0054] After loading into the freeze dryer, the PBMC are freeze-dried, typically over a 5-day cycle. Residual moisture content after freeze drying is typically 0.35%.
[0055] Once fixative has been washed from the stimulated cells, the PBMC begin to leak cytokines, albeit slowly at low temperatures. Therefore, loading into aliquots and freeze drying of PBMC is performed within a few hours of fixative removal.
[0056] Following freeze-drying, the lyophilised reference materials may be stored for extended periods of time without degradation. The freeze-dried samples may be reconstituted in twice the starting volume of distilled water. This typically gives cells in single-strength phosphate buffered saline.
[0057] In a further embodiment of the invention, fractions of cells rich in a particular cell type may be isolated from a mixed population of PMBC and subjected to the stimulation and fixing regime described above before being re-combined with fixed, unstimulated cells.
[0058] In this way, cell populations with different levels of cytokines in specific cell types may be produced to mimic particular disease states. Particular cell types may be isolated by a number of means such as flow cytometry and cell-sorting, or by the use of antibody-linked magnetic beads, available commercially. Such separation techniques may be used to isolate e.g. B cells, monocytes, natural killer cells, neutrophils, platelets, etc., as well as particular subsets such as CD4 and CD8 T-cells. Again, such populations of differentially-stimulated cells may be diluted with unstimulated, fixed cells to produce cell populations that are a closer mimic to those found in particular disease states.
[0059] Cell reference standards produced according to methods of the invention may be reconstituted by addition of water, and used in cytokine assays. The cells retain surface antigens, as well as intracellular cytokines. They may be subjected, therefore, to staining techniques used in the art and used as reference standards for e.g. flow cytometry. Furthermore, the cells remain intact, and yet capable of releasing cytokines into their immediate environment, especially when held at elevated temperatures, e.g. 37° C., as commonly used in ELISPOT assays. They may therefore be used as reference standards in this type of assay.
[0060] Storage trials have demonstrated that the lyophilised cells retain their properties after storage for 5 months, with indications that they have a shelf life of many years, allowing them to be used as repeatable standards for long-term studies and diagnosis.
[0061] As well as being useful as reference standards, the freeze-dried cells produced by the methods described herein can also find use as vaccines as the cells' surface antigens are maintained in an intact state by the fixing and freeze drying process.
Example 2
[0062] Production of Cell proliferation Standards
[0063] By way of an example, the methods disclosed herein may be used to produce reference standards for assay of proliferation of peripheral blood mononuclear cells (PBMC). In one embodiment of the invention, “buffy coats” are obtained e.g from phlebotomised donors or a national blood collection agency. The buffy coat fraction of blood is that portion of blood that, following centrifugation, contains the majority of the white blood cells and platelets. All such obtained buffy coats will typically be tested to ensure they are negative for Treponema pallidum haem-agglutination test (“TPHA”), Hepatitis B surface antigent (“HBsAg”), anti Human Immunodeficiency Virus 1 (“anti-HIV1”), anti-Human Immunodeficiency Virus 2 (“anti-HIV 2”) and anti Hepatitis C Virus (“anti-HCV”) prior to use.
[0064] Residual erythrocytes contained within the buffy coats are removed by application of any standard, commercially available lymphocyte density gradient preparation, such as Lymphoprep, and peripheral blood mononuclear cells (“PBMC”) are subsequently isolated/collected, again by application of a lymphocyte density gradient preparation. The PBMC are then washed in a mammalian cell culture medium such as RPMI 1640 media.
[0065] These PBMC are then labeled with a fluorescent dye such as the commercially-available carboxyfluorescein succinimidyl ester (“CFSE”) or carboxyfluorescein succinimidyl ester (“CFDA-SE”). An example of one such dye is known by the trade name CellTrace CFSE Cell proliferation Kit. The labeled cells are then stimulated to induce proliferation for 70-74 hours with the monoclonal antibody UCHT1, prior to being stabilized with a fixative and freeze-dried or cryopreserved. Stimulation is typically carried out within an environment containing 4-6% carbon dioxide, and at a temperature of 36-38° C. This stimulation induces cell proliferation. In other embodiments, a combination of immuno-stimulants are used, said stimulants commonly comprising phorbol 12-myristate 13-acetate (PMA) (applied at a concentration of 0.01-0.03 μg per ml, say 0.02 μg per ml) and Ionomycin (applied at a concentration of 0.125-0.165 μg per mg, say 0.145 μg per mg). Following such stimulation, proliferation takes place within typically 70-74 hours.
[0066] Following proliferation to the degree required (depending on the reference material to be produced), the PBMC are washed in a combination of foetal calf serum (“FCS”) and phosphate buffered saline (“PBS”), the FCS being used typically at a concentration of 9-12% v/v, say 10% and the PBS typically being double strength.
[0067] The washed PBMS are then re-suspended in a buffered culture medium (again comprising double strength PBS and 9-12% FCS), with the addition of 20% (v/v) of a commercially available transport fixative containing a combination of paraformaldehyde (0.1-0.2% w/v) and chromium chloride (0.5% w/v) in 0.85% (w/v) PBS. An example of one such fixative is known by the trade name “TransFix”. The buffered culture medium and fixative is applied to the said PBMC at a rate of 8×10 6 PBMC per ml.
[0068] After fixing, the PBMC are subsequently washed with chilled (+4° C.) freeze drying buffer (a cryoprotectant). A typical buffer would comprise a double volume of 10% protein, typically, foetal calf serum or albumin in double strength PBS. The use of a freeze drying buffer improves PBMC stability during the subsequent freeze drying process. These cells may then be stored at chill temperatures (typically +4° C.) before freeze-drying. In order to optimise the quality and consistency of the reference standards, the shelves of a freeze dryer are pre-cooled in order to maintain a temperature of +4° C. during the loading process.
[0069] The labeled, proliferated, fixed cells are then loaded into aliquots/capped vials. A filling machine such as one sold under the trade name Paxal, is suitable for large scale aliquoting.
[0070] After loading into the freeze dryer, the PBMC are freeze-dried, typically extended over a 5-day cycle. Residual moisture content after freeze drying is typically 0.35%.
[0071] Following freeze-drying, the lyophilised reference materials may be stored for extended periods of time without degradation. The freeze-dried samples may be reconstituted in twice the starting volume of distilled water. This typically gives cells in single-strength phosphate buffered saline.
[0072] In a further embodiment of the invention, fractions of cells rich in a particular cell type may be isolated from a mixed population of PMBC and subjected to the labeling, proliferation and fixing regime described. In this way, cell populations with different degrees of proliferation in specific cell types may be produced. Particular cell types may be isolated by a number of means such as flow cytometry and cell-sorting, or by the use of antibody-linked magnetic beads, available commercially. Such separation techniques may be used to isolate e.g. B cells, monocytes, natural killer cells, neutrophils, platelets, etc., as well as particular subsets such as CD4 and CD8 T-cells. Again, such populations of differentially-proliferating cells may be diluted with labeled, “un-proliferated” fixed cells to produce cell populations that are a closer mimic to those found in particular disease states.
[0073] Cell reference standards produced according to methods of the invention may be reconstituted by addition of water, and used as reference standards for cell proliferation assays. The cells retain surface antigens suitable for subset analysis. They may be subjected, therefore, to staining techniques used in the art and used as reference standards for e.g. flow cytometry.
[0074] Storage trials have demonstrated that the lyophilised cells retain their properties after storage for 5 months, with indications that they have a shelf life of many years, allowing them to be used as repeatable standards for long-term studies and diagnosis. | Methods for producing stimulated, positive and negative control reference standard for monitoring intracellular cytokine levels and cytokine release in test samples by stimulating cells to produce cytokines in the presence of a cytokine release inhibitor, fixing the stimulated cells with a fixative such as paraformaldehyde, washing to remove excess fixatives and freeze-drying the stimulated, fixed cells. Methods for producing labeled reference standards for cell proliferation assays are also disclosed, in which proliferation-competent mammalian cells, isolated from a human or animal body are labeled with a label, such as a dye, that is divided between daughter cells during cell proliferation (e.g., carboxyfluorescein succinimidyl ester), the cells are stimulated to proliferate, the proliferated cells are fixed by addition of a fixative and then preserved by freeze drying or cryopreservation. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to stable colloidal aqueous dispersions of partially and homogeneously crosslinked polyurethane/polyurea adhesives that are heat activatable at 70° C., and have high bond strengths and good heat resistance at 70° C. It relates more particularly to dispersions wherein the average size of the adhesive particles is about 0.12 micron and in which the particle size distribution is very narrow.
Chemical resistance, toughness, elasticity, and durability are desirable properties of polyurethane/polyurea resins (sometimes referred to hereinafter as PUR resins) used as adhesives and coatings for fabrics, plastics, wood, glass fibers, and metals. Good initial green strength, a low heat activation temperature, and high heat resistance are necessary properties of such resins when they are being considered for use as adhesives in the manufacture of such dissimilar products as automobiles and shoes. Prior to this invention, two-component systems (e.g., a PUR resin+an ethylene vinyl acetate polymer) have been used generally to provide the combination of high heat resistance, good contactability, good green strength, and low activation temperature required by auto manufacturers for their assembly of dashboards and door panels, and installation of carpets and headliners. External crosslinking agents usually have been required for the PUR resin adhesives of the prior art. One U.S. auto manufacturer's specifications require an aqueous dispersion of an adhesive that achieves good bond strength when activated on the substrate at 70° C. without the need for an external crosslinking agent and retains that strength upon prolonged exposure to such heat.
The shoe industry requires its adhesives to have very high initial tack and green strength, quick bonding of PVC, rubber, fabric, and leather substrates, and excellent heat- and water resistance. It has been very slow to adapt to aqueous adhesives because of such requirements.
Aqueous dispersions of anionic polyurethane compositions which can be one component or two component adhesives are taught in U.S. Pat. No. 5,608,000, which is incorporated herein by reference. The polyurethane backbone of the adhesive of said patent comprises the reaction product of an isocyanate terminated prepolymer, a chain extending diamine, and a chain stopping aminoalcohol. A sulfonated polyester polyol group is incorporated into the polyurethane as an internal emulsifier. Conventional crosslinkers for isocyanate-terminated polyurethanes are taught to be less than optimal because their use requires a high level of chain extending diamine which makes it more difficult to maintain a stable dispersion. The preferred method of crosslinking, according to this patent, is by reaction at room temperature of carboxylic acid groups incorporated in the polyurethane with a crosslinker such as a polyfunctional aziridine compound.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a polyurethane/polyurea which is partially and homogeneously crosslinked with a triamine to give a stable aqueous dispersion which is useful as a low-temperature heat activatable adhesive.
It is another object of the invention to provide a stable, colloidal aqueous dispersion of a polyurethane/polyurea adhesive which can be activated when heated to about 60-70° C.
It is another object of the invention to provide a partially crosslinked polyurethane/polyurea adhesive that provides good initial green strength and is heat resistant at 70° C.
These and other objects which will become apparent from the following description of the invention are achieved by a stable aqueous dispersion of a heat-activatable adhesive comprising a partially and homogeneously cross-linked polyurethane/polyurea wherein the polyurethane segment contains an integral ionic emulsifier and the polyurea segment, which contains an integral emulsion stabilizer, is a product of a chain extension of an isocyanate-terminated polyurethane with mixture of amines comprising an aliphatic diamine and an aliphatic triamine having three primary amino groups, said mixture having a functionality of from 2.05 to 2.18, and, optionally, reacting a portion of the isocyanate-terminated polyurethane with a monoaminoalkanol, an aminoacid, a vinyl-substituted amine, or amixture of two or more of said amines.
Said objects are achieved also by a process for the preparation of a stable aqueous dispersion of a partially cross-linked polyester-based polyurethane/polyurea which comprises:
a) forming a solution in a high boiling, water-soluble organic solvent that is inert toward the isocyanate group of at least about 36% by weight of a dihydroxycarboxlic acid having up to 12 carbon atoms at from about 40 to about 80° C.;
b) forming an isocyanate-terminated polyurethane by reacting a stoichiometric excess of an aliphatic diisocyanate with a polyesterdiol or polycaprolactone diol or mixture thereof with from about 0.02 to about 0.05 of said dihydroxycarboxlic acid per hundred grams of final dry polyurethane/polyurea;
c) adding a water-soluble ketone before or after the reaction occurs to form a solution of the isocyanate-terminated polyurethane;
d) adding a monoamine containing a hydrophilic oxyalkylene moiety with a second portion of the diisocyanate, and neutralizing the carboxylic acid moiety with a tertiary amine;
e) dispersing the isocyanate-terminated polyurethane in water by adding water to the ketone solution thereof at a rate of from about 600 to about 900 mls/sec;
f) forming a mixture of ketimines by dissolving an aliphatic diamine and an aliphatic amine having three primary amino groups in a water-soluble ketone, the amine mixture having a functionality of from 2.05 to 2.18;
g) optionally, adding a monoaminoalkanol, an aminoacid, a vinyl substituted amine, or a mixture of said amines to the amine mixture, and
h) adding the mixture of ketimines to the aqueous dispersion, whereby the ketimines hydrolyze to the original amines and ketone, and reacting the amines with the isocyanate-terminated polyurethane to form the polyurethane/polyurea, and removing the water-soluble ketone by distillation.
FIG. 1 is a graph of the particle size of the adhesive.
DETAILED DESCRIPTION OF THE INVENTION
The polyesterdiols used in the preparation of a polyurethane are preferably linear and have a weight average molecular weight of from about 750 to about 5600, preferably greater than about 1600 and more preferably from about 2800 to about 3200. The hydroxyl number may be from about 20 to about 150 but is preferably from about 20 to about 70 and more preferably from about 30 to about 40. They may be produced by a conventional procedure in which one or more dicarboxylic acids and one or more glycols are heated in the presence of an acid catalyst until the acid number is reduced to about 30 or less, preferably less than 1, more preferably less than 0.8. Transesterification of a dicarboxylic acid ester by reaction with one or more of such glycols is also suitable. The glycol to acid mole ratio is preferably greater than one so as to obtain linear chains having a preponderance of terminal hydroxyl groups.
The ester-forming glycols may be aliphatic, cycloaliphatic, aromatic or mixtures thereof. Examples of the glycol component include alkylene glycols having from 2 to 10 carbon atoms as exemplified by ethylene glycol, 1,2-propanediol, 1,4-butanediol, 2,6-hexamethylenediol, and mixtures thereof. ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 2-methyl-1,3-propane diol; 2-butyl-2-ethyl-1,3-propane diol; 2,2,4-trimethyl-1,3-pentanediol; cyclohexanedimethanol, ethylene oxide and propylene oxide adducts of bisphenol A, ethylene oxide and propylene oxide adducts of hydrogenated bisphenol A, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like.
The dicarboxylic acid component of the polyesterdiol is predominantly aliphatic and includes cycloaliphatic acids, aromatic acids which have aliphatic substituents of eight or more carbon atoms, and mixtures thereof. Suitable aliphatic dicarboxylic acids include succinic, adipic, azelaic, sebacic, and dodecanedioc acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, hydrogenated 2,6-naphthalenedicarboxylic acid and the like. An anhydride may be used in place of or with the acid.
Polyesterdiols made from adipic acid and 1,6-hexanediol or 1,4-butanediol and mixtures thereof are preferred for the purposes of this invention.
The average molecular weight of the polycaprolactone diols used as intermediates in the preparation of a polyurethane of this invention is the same that given above for the polyesterdiols. The polycaprolactone diols are made by the reaction of caprolactone and an excess of an alkylene glycol in accordance with conventional procedures.
The amount of the dihydroxycarboxylic acid in admixture with the diol is from about 0.02 to about 0.05 equivalent per hundred grams of the final polyurethane/polyurea being made after drying. The α,α-dimethylol alkanoic acids are preferred as the dihydroxycarboxylic acid; 2,2-dimethylolpropionic acid is particularly preferred. The diol reacts with the diisocyanate along with the polyesterdiol and imparts its potential ionic character to the isocyanate-terminated prepolymer (i.e., the polyurethane) first formed in the method of this invention. The high boiling, water-soluble solvent is inert toward the isocyanate group and has a boiling point of from 160 to 210° C.; it is exemplified by N-methyl-2-pyrrolidone. The introduction of the acid into the diol as a solution in the high boiling solvent promotes a quick and thorough distribution of the acid in the diol before the introduction of the diisocyanate and prevents isolated localized reactions of the diisocyanate with solid particles of the acid. The high concentration of the acid in the solution minimizes the amount of high boiling solvent that remains in the stripped aqueous dispersion and ultimately in the adhesive. A low concentration of the high boiling solvent is preferred in order to obtain an adhesive having good green strength and good heat resistance when the functionality of the mixture of chain extending diamines and crosslinking triamines is so low as in this invention. For that reason, the amount of high boiling solvent in the aqueous dispersion is from about 1.0 to about 1.5%, preferably about 1.2%, by weight.
After conversion of the potentially ionic carboxylic group to an ionic group by salt formation with the tertiary amine, the concentration of ionic groups in the polyurethane may be from about 0.005 to about 0.015 per 100 grams but it is preferably about 0.013 equivalent per 100 grams. Too much of the ionic group will prevent the heat activation of the adhesive at 60-70° C. that is so important.
The maximum diisocyanate content of the diol/diisocyanate mixture is about 25% by weight and it is preferred to be from about 12 to about 18%. Suitable diisocyanates are predominantly aliphatic in character and are exemplified by isophorone diisocyanate; m-tetramethylxylenediisocyanate; ptetramethylxylene diisocyanate; 4,4′-diisocyanatodicyclohexane; tetramethylenediisocyanate; 1,4-diisocyanatomethylcyclohexane; 4,4′-diisocyanatodicyclohexylmethane; 1,6-hexanediisocyanate, and 1,3-diisocyanatomethylcyclohexane.
In a preferred embodiment of the method of this invention, the mixture of the diol and the solution of the acid in the high boiling water-soluble solvent are heated to a temperature of from about 80 to about 100° C. and then the diisocyanate is added in one quick charge. The reaction is exothermic but it is preferred to hold the temperature at from about 85 to 90° C. Vigorous stirring is maintained in this and the following steps.
It is desirable to use a water-soluble ketone to dilute the prepolymer so as to maintain the reactants in the liquid state and help control the temperature during the next steps of the method for preparing the aqueous dispersions of this invention. At this stage, the amount of ketone is from about 20 to about 30%, by weight, of the total solution. The ketone is also a reactant in the formation of blocked amines known as ketimines in the next step of the method. A super-atmospheric pressure may be imposed to prevent boiling of the ketone.
After the isocyanate-terminated prepolymer has been dissolved in acetone or other water soluble ketone, an internal stabilizer is formed in the polyurethane by reacting from about 4 to about 6%, preferably about 5%, by weight of the polyurethane, of a hydrophilic oxyalkylene group-containing monoamine with the equivalent amount of the excess diisocyanate. The internal stabilizer thus comprises hydrophilic urea groups on the polyurethane chain. The hydrophilic monoamine may be made by alkoxylating an alkanolamine with ethylene oxide or propylene oxide or a mixture of the two. The weight average molecular weight of the monoamine is from about 600 to about 2000. An alkoxylated hydroxypropylamine having a polyethylene glycol backbone and containing 30% by weight of randomly incorporated propylene oxide, sold under the trademark JEFFAMINE M-2070 by the Huntsman Corporation, is particularly preferred for the preparation of an adhesive of this invention. A propylene oxide adduct of an aminoalkyl phenol, available from Clariant Corporation, and having the formula H 2 NCH 2 CH(CH 3 )C 6 H 4 O—(CH 2 CH(CH 3 )CH 2 O) 30 H, is also suitable.
It is preferred to dissolve the monoamine in the ketone and allow the solution to age for at least about 2 hours to form a ketimine before it is added to the prepolymer to facilitate thorough mixing of the reactants. The ketimine releases the amine to react with the terminal isocyanate groups at a temperature of from about 35 to about 40° C. The amount of hydrophilic monoamine used, based on the weight of the dry polyurethane/polyurea being made, is from about 0.002 to about 0.008 equivalent per 100 grams of the polyurethane/polyurea.
The conversion of the carboxylic acid moiety in the polyurethane to an anionic group may be undertaken along with the formation of the internal stabilizer by adding a tertiary amine to the solution of the monoamine. Tertiary amines lacking active hydrogens as determined by the Zerewitinoff test are preferred because they would be capable of reacting with the isocyanate groups of the prepolymer and cause gelation or chain termination. A trialkyl-substituted amine such as triethylamine is particularly preferred.
In contrast to procedures in the prior art, wherein water is added slowly to the polyurethane prepolymer, the formation of an aqueous dispersion of the anionic polyurethane prepolymer with urea groups derived from the monoamine is achieved in this invention by adding cool water (˜50° F.; ˜10° C.) at a minimum rate of about 600, preferably about 900, mls/sec (from about 1 to 1.5 gallons per minute) or more quickly if possible. The quick addition has the effects of hydrolyzing all of the ketimine to the monoamine very quickly to free the amine for reaction with an equivalent portion of the diisocyanate remaining in the reaction mixture and cooling the reaction mixture quickly to about 15-25° C., preferably less than about 20° C., to minimize reaction between the water and the diisocyanate.
High bond strengths and heat resistance at 70° C. are achieved by the chain extension of the polyurethane with from about 0.033 to about 0.038 equivalent of a diamine per hundred grams of the dry final polymer and a homogeneously partial crosslinking of the polymer with from about 0.002 to about 0.007 equivalent per hundred grams of the dry final polymer of a triamine in which all of the amino groups are primary and thus have the same reactivity. Examples of a suitable triamine include 1,5,11-triaminoundecane, tris(2-aminoethyl)amine, and, preferably, 4-aminomethyl-1,8-diamino octane (also known as triaminonane or TAN). Other tri- or higher poly-amines in which all of the amino groups are primary may also be used.
Suitable diamines include ethylenediamine, propylenediamine, 1,4-butylenediamine; 1,3-pentanediamine, hexamethylenediamine, 2-methylpentamethylenediamine, 1,4-cyclohexyldimethyldiamine, isophorone diamine, and, preferably, 1,2-diaminocyclohexane (or DCH).
All of the amino groups in the chain extender and in the crosslinker are primary.
To achieve a homogeneous chain extension and homogeneous partial crosslinking, the amines are blocked by reaction with a water-soluble ketone to form a ketimine. A mixture of the amines is aged in the ketone solution for at least about 2 hours. Acetone is a preferred ketone. To take advantage of the low temperature of the reaction mixture after the water cooling step, the ketimines are preferably added within about 15 minutes of the water addition at a rate of about 20-30 grams per minute. The ketimines are hydrolyzed immediately to the corresponding diamine and triamine and the high dilution of the polyurethane prepolymer in the aqueous dispersion favors the homogeneous crosslinking wherein a large proportion of individual chains are crosslinked rather than a few chains being highly crosslinked while some chains are not crosslinked at all.
The final product is a stable aqueous dispersion of colloidally sized particles of a partially crosslinked polyurethane/polyurea having a solids content of from 50-55% by weight and a viscosity of about 500-600 cps and in which the particle size distribution is from 0.07 to 0.24 micron (see FIG. 1) and the average particle size is about 0.12 micron (120 nanometers). The dispersed adhesive has excellent green strength.
The option of adding an aminoalcohol is chosen when the homogeneous partial crosslinking of the polyurethane/polyurea by the mix of diamines and triamines having a functionality of 2.18 or less yields a softening point which is too low when the adhesive is to be used in tropical areas of the world. In that situation, an additional charge of diisocyanate may be added to crosslink two chains containing hydroxyl groups furnished by the aminoalcohol. Ethanolamine, propanolamine, butanolamine, and N-methylethanolamine are examples of suitable aminoalcohols. The choice of an aminoacid provides carboxylic acid groups on the polyurea segment which enhance the adhesive power of the polyurethane/polyurea of this invention. Examples of an amino acid include glycine and 6-aminocaproic acid. The reaction of a vinyl-substituted primary amine with isocyanate groups remaining on the polyurethane/polyurea provides sites for radiation curing of the adhesive with ultra-violet light or an electron beam with the aid of photoactivated initiators and accelerators. An aminostyrene is an example of a vinyl-substituted amine.
Additives such as anti-foam agents, biocides, fillers, dyes, and pigments may be added to impart desirable properties to the dispersion and/or to the adhesive in it.
The end products of the process of this invention are suitable as adhesives for textiles, leather, paper, cardboard, wood, glass, metals, ceramics, foamed resins, and plastics.
The dispersion is applied to such substrates and dried at from 60-70° C. for 15-20 minutes in an oven, the substrates are removed and the surfaces are again heated to 60-70° C. to activate the adhesive and the substrates are pressed together to form a bond.
The invention is illustrated further but is not limited by the following examples.
EXAMPLE 1
A solution containing 36.4% by weight of dimethylol propionic acid in a high boiling solvent was prepared by holding a mixture of 279 grams (4.16 eq.) of dimethylol propionic acid and 489 grams of N-methyl-2-pyrrolidone at 40° C. until all solids disappeared. The hot solution was added to 12,187 grams (8.34 equivalents) of a molten polyesterdiol (1,6 hexanediol plus adipic acid; OH#38.39) with stirring and the temperature was at 80-85° C. when 2364 grams (21.3 eq.) of isophorone diisocyanate was added quickly. The exothermic reaction raised the temperature to about 95° C. and the reaction was continued at 85-90° C. for about 4 hours. Then 5044 grams of acetone at room temperature was added to the prepolymer and mixing was continued for about 30 minutes as the temperature was reduced to about 35-40° C. Then, a solution of 834 grams (4.03 eq.) of a monoamine of a polyethylene/polypropylene glycol (Jeffamine 2070) and 211 grams (2.08 eq) of triethylamine in 834 grams of acetone (the solution having been aged at room temperature for 15 hrs) was added and the mixture was stirred for about 30 minutes. The mixer speed was increased to 240 rpm and 15,362 grams of de-ionized water was added in about 20 seconds. After about 5 minutes of stirring, the temperature had dropped to about 17° C. With the mixer at 240 rpm, a solution of 310 grams (5.43 eq) of diaminocyclohexane, 68 grams (1.17 eq.) of triaminononane, and 131.6 grams (1.75 eq) of 3-aminopropanol in 1468 grams of acetone (the solution having been aged at room temperature for 15 hrs) was metered into the prepolymer solution in about 10 minutes. The reaction mixture was stirred for about 5 minutes. A mixture of 6.5 grams of Foam Master AP anti-foam agent, 65 grams of AMICAL biocide, and 550 grams of de-ionized water was added to the stirred dispersion and the acetone was stripped off under a reduced pressure of 10 mmHg at 17-29° C. to yield an aqueous dispersion containing 49% of the adhesive solids of this invention. The Brookfield viscosity was 540 cps (spindle #2, 20 rpm, 23° C., Brookfield RVT).
The dispersion was applied to a strip of rubber, the strip was cut in half, dried in an oven at 70° for about 15 minutes, and folded over itself so as to bring the adhesive layers into contact. The folds were pressed together and returned to the 70° oven for 10 minutes. The strips were then removed and the aperture, if any, between the folded halves of the strip was measured as a test of the initial bond strength (green strength). No separation was observed.
The heat resistance of the adhesive was measured as follows: The dispersion was applied to two 12 cm long cotton strips and dried at room temperature. The adhesive was activated on each strip by heat from an infra-red lamp and the two strips were bonded together immediately, except for a portion at the end of each, in a hydraulic press. After 24 hours, a 2.27 kg weight was hung from the unbonded area of the strip and it was placed in an oven for 3 hours as the temperature was increased from 50 to 70° C. No failure of the adhesive was observed at the end of the test period. | A stable colloidal aqueous dispersion of a partially and homogeneously crosslinked polyurethane/polyurea is made by inserting an integral emulsifier and an internal dispersion stabilizer into a polyurethane having a polyester- or polycaprolactone diol backbone and chain extending and crosslinking it with a mixture of diamine and triamine having a functionality of from 2.05 to 2.18. A highly concentrated solution of a dihydroxycarboxylic acid in a solvent such as N-methyl pyrrolidone permits the hydroxyl groups to react thoroughly and quickly with an isocyanate-terminated polyurethane and, consequently, a minimal amount of the solvent is present in the adhesive after water is removed from the aqueous dispersion. The adhesive is thus heat resistant at 70° C. despite its relatively small degree of crosslinking. | 2 |
This application is a continuation-in-part of DiMarchi et al., U.S. Ser. No. 08/38/,003, filed Jan. 31, 1995, docket number X-9928 now abandoned.
FIELD OF THE INVENTION
The present invention is in the field of human medicine, particularly in the treatment of obesity and disorders associated with obesity. Most specifically the invention relates to anti-obesity proteins that when administered to a patient regulate fan tissue.
BACKGROUND OF THE INVENTION
Obesity, and especially upper body obesity, is a common and very serious public health problem in the United States and throughout the world. According to recent statistics, more than 25% of the United States population and 27% of the Canadian population are over weight. Kuczmarski, Amer. J of Clin. Nut. 55: 495S-502S (1992); Reeder et. al., Can. Med. Ass. J., 23: 226-233 (1992). Upper body obesity is the strongest risk factor known for type II diabetes mellitus, and is a strong risk factor for cardiovascular disease and cancer as well. Recent estimates for the medical cost of obesity are $150,000,000,000 world wide. The problem has become serious enough that the surgeon general has begun an initiative to combat the ever increasing adiposity rampant in American society.
Much of this obesity induced pathology can be attributed to the strong association with dyslipidemia, hypertension, and insulin resistance. Many studies have demonstrated that reduction in obesity by diet and exercise reduces these risk factors dramatically. Unfortunately these treatments are largely unsuccessful with a failure rate reaching 95%. This failure may be due to the fact that the condition is strongly associated with genetically inherited factors that contribute to increased appetite, preference for highly caloric foods, reduced physical activity, and increased lipogenic metabolism. This indicates that people inheriting these genetic traits. are prone to becoming obese regardless of their efforts to combat the condition. Therefore, a new pharmacological agent that can correct this adiposity handicap and allow the physician to successfully treat obese patients in spite of their genetic inheritance is needed.
The ob/oh mouse is a model of obesity and diabetes that is known to carry an autosomal recessive trait linked to a mutation in the sixth chromosome. Recently, Yiying Zhang and co-workers published the positional cloning of the mouse gene linked with this condition. Yiying Zhang et al. Nature 372: 425-32 (1994). This report disclosed a gene coding for a 167 amino acid protein with a 21 amino acid signal peptide that is exclusively expressed in adipose tissue. The report continues to disclose that a mutation resulting in the conversion of a codon for arginine at position 105 to a stop codon results in the expression of a truncated protein, which presumably is inactive.
Physiologist have postulated for years that, when a mammal overeats, the resulting excess fat signals to the brain that the body is obese which, in turn, causes the body to eat less and burn more fuel. G. R. Hervey, Nature 227:629-631 (1969). This "feedback" model is supported by parabiotic experiments, which implicate a circulating hormone controlling adiposity. Based on this model, the protein, which is apparently encoded by the ob gene, is now speculated to be an adiposity regulating hormone.
Pharmacological agents which are biologically active and mimic the activity of this protein are useful to help patients regulate their appetite and metabolism and thereby control their adiposity. Until the present invention, such a pharmacological agent was unknown.
The present invention provides biologically active anti-obesity proteins. Such agents therefore allow patients to overcome their obesity handicap and live normal lives with a more normalized risk for type II diabetes, cardiovascular disease and cancer.
SUMMARY OF INVENTION
The present invention is directed to a biologically active anti-obesity protein of the Formula (I): ##STR1## wherein: Xaa at position 4 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 7 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 22 of SEQ ID NO: 1 is Gln, Ash, or Asp;
Xaa at position 27 of SEQ ID NO: 1 is Thr or Ala;
Xaa at position 28 of SEQ ID NO: 1 is Gln, Glu, or absent;
Xaa at position 34 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 54 of SEQ ID NO: 1 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, or Gly;
Xaa at position 56 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 62 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 63 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 68 of SEQ ID NO: 1 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, or Gly;
Xaa at position 72 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 75 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 78 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 82 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 100 of SEQ ID NO: 1 is Gln, Trp, Tyr, Phe, Ile, Val, or Leu;
Xaa at position 8 of SEQ ID NO: 2 is Asp or Glu;
Xaa at position 30 of SEQ ID NO: 2 is Gln or Glu;
Xaa at position 34 of SEQ ID NO: 2 is Gln or Glu;
Xaa at position 36 of SEQ ID NO: 2 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, or Gly;
Xaa at position 38 of SEQ ID NO: 2 is Gln, Trp, Tyr, Phe, Ile, Val, or Leu; and
Xaa at position 39 of SEQ ID NO: 2 is Gln or Glu.
The invention further provides a method of treating obesity, which comprises administering to a mammal in need thereof a protein of the Formula (I).
The invention further provides a pharmaceutical formulation, which comprises a protein of the Formula (I) together with one or more pharmaceutical acceptable diluents, carriers or excipients therefor.
DETAILED DESCRIPTION
As noted above the present invention provides a protein of the Formula (I): ##STR2## wherein: Xaa at position 4 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 7 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 22 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 27 of SEQ ID NO: 1 is Thr or Ala;
Xaa at position 28 of SEQ ID NO: 1 is Gln, Glu, or absent;
Xaa at position 34 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 54 of SEQ ID NO: 1 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, or Gly;
Xaa at position 56 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 62 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 63 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 68 of SEQ ID NO: 1 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, or Gly;
Xaa at position 72 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 75 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 78 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 82 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 100 of SEQ ID NO: 1 is Gln, Trp, Tyr, Phe, Ile, Val, or Leu;
Xaa at position 8 of SEQ ID NO: 2 is Asp or Glu;
Xaa at position 30 of SEQ ID NO: 2 is Gln or Glu;
Xaa at position 34 of SEQ ID NO: 2 is Gln or Glu;
Xaa at position 36 of SEQ ID NO: 2 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, or Gly;
Xaa at position 38 of SEQ ID NO: 2 is Gln, Trp, Tyr, Phe, Ile, Val, or Leu; and
Xaa at position 39 of SEQ ID NO: 2 is Gln or Glu.
The preferred proteins of the present invention are those of Formula (I) wherein: wherein:
Xaa at position 4 of SEQ ID NO: 1 is Gln;
Xaa at position 7 of SEQ ID NO: 1 is Gln;
Xaa at position 22 of SEQ ID NO: 1 is Asn;
Xaa at position 27 of SEQ ID NO: 1 is Thr;
Xaa at position 28 of SEQ ID NO: 1 is Gln;
Xaa at position 34 of SEQ ID NO: 1 is Gln;
Xaa at position 54 of SEQ ID NO: 1 is Met;
Xaa at position 56 of SEQ ID NO: 1 is Gln;
Xaa at position 62 of SEQ ID NO: 1 is Gln;
Xaa at position 63 of SEQ ID NO: 1 is Gln;
Xaa at position 68 of SEQ ID NO: 1 is Met;
Xaa at position 72 of SEQ ID NO: 1 is Asn;
Xaa at position 75 of SEQ ID NO: 1 is Gln;
Xaa at position 78 of SEQ ID NO: 1 is Asn;
Xaa at position 82 of SEQ ID NO: 1 is Asn;
Xaa at position 100 of SEQ ID NO: 1 is Trp;
Xaa at position 8 of SEQ ID NO: 2 is Asp;
Xaa at position 30 of SEQ ID NO: 2 is Gln;
Xaa at position 34 of SEQ ID NO: 2 is Gln;
Xaa at position 36 of SEQ ID NO: 2 is Met;
Xaa at position 38 of SEQ ID NO: 2 is Trp; and
Xaa at position 39 of SEQ ID NO: 2 is Gln.
The amino acids abbreviations are accepted by the United States Patent and Trademark Office as set forth in 37 C.F.R. §1.822 (b)(2) (1993). One skilled in the art would recognize that certain amino acids are prone to rearrangement. For example, Asp may rearrange to aspartimide and isoasparigine as described in I. Schon et al., Int. J. Peptide Protein Res. 14:485-94 (1979) and references cited therein. T rearrangement derivatives are included within the scope of the present invention. Unless otherwise indicated the amino acids are in the L configuration.
For purposes of the present invention, as disclosed and claimed herein, the following terms and abbreviations are defined as follows: SEQ ID NO;1 properly crosslinked to SEQ ID NO:2 refers to the formation of a disulfide bond between cysteine residues at position 96 of SEQ ID NO: 1 and position 46 of SEQ ID NO: 2 as depicted in Formula I.
Base pair (bp)--refers to DNA or RNA. The abbreviations A,C,G, and T correspond to the 5'-monophosphate forms of the nucleotides (deoxy)adenine, (deoxy)cytidine, (deoxy)guanine, and (deoxy)thymine, respectively, when they occur in DNA molecules. The abbreviations U,C,G, and T correspond to the 5'-monophosphate forms of the nucleosides uracil, cytidine, guanine, and thymine, respectively when they occur in RNA molecules. In double stranded DNA, base pair may refer to a partnership of A with T or C with G. In a DNA/RNA heteroduplex, base pair may refer to a partnership of T with U or C with G.
Chelating Peptide--An amino acid sequence capable of complexing with a multivalent metal ion.
DNA--Deoyxribonucleic acid.
EDTA--an abbreviation for ethylenediamine tetraacetic acid.
ED 50 --an abbreviation for half-maximal value.
FAB-MS--an abbreviation for fast atom bombardment mass spectrometry.
Immunoreactive Protein(s)--a term used to collectively describe antibodies, fragments of antibodies capable of binding antigens of a similar nature as the parent antibody molecule from which they are derived, and single chain polypeptide binding molecules as described in PCT Application No. PCT/US 87/02208, International Publication No. WO 88/01649. 5 mRNA--messenger RNA.
MWCO--an abbreviation for molecular weight cut-off.
Plasmid--an extrachromosomal self-replicating genetic element.
PMSF--an abbreviation for phenylmethylsulfonyl fluoride.
Reading frame--the nucleotide sequence from which translation occurs "read" in triplets by the translational apparatus of tRNA, ribosomes and associated factors, each triplet corresponding to a particular amino acid. Because each triplet is distinct and of the same length, the coding sequence must be a multiple of three. A base pair insertion or deletion (termed a frameshift mutation) may result in two different proteins being coded for by the same DNA segment. To insure against this, the triplet codons corresponding to the desired polypeptide must be aligned in multiples of three from the initiation codon, i.e. the correct "reading frame" must be maintained. In the creation of fusion proteins containing a chelating peptide, the reading frame of the DNA sequence encoding the structural protein must be maintained in the DNA sequence encoding the chelating peptide.
Recombinant DNA Cloning Vector--any autonomously replicating agent including, but not limited to, plasmids and phages, comprising a DNA molecule to which one or more additional DNA segments can or have been added.
Recombinant DNA Expression Vector--any recombinant DNA cloning vector in which a promoter has been incorporated.
Replicon--A DNA sequence that controls and allows for autonomous replication of a plasmid or other vector.
RNA--ribonucleic acid.
RP-HPLC--an abbreviation for reversed-phase high performance liquid chromatography.
Transcription--the process whereby information contained in a nucleotide sequence of DNA is transferred to a complementary RNA sequence.
Translation--the process whereby the genetic information of messenger RNA is used to specify and direct the synthesis of a polypeptide chain.
Tris--an abbreviation for tris(hydroxymethyl)-aminomethane.
Treating--describes the management and care of a patient for the purpose of combating the disease, condition, or disorder and includes the administration of a compound of present invention to prevent the onset of the symptoms or complications, alleviating the symptoms or complications, or eliminating the disease, condition, or disorder. Treating obesity therefor includes the inhibition of food intake, the inhibition of weight gain, and inducing weight loss in patients in need thereof.
Vector--a replicon used for the transformation of cells in gene manipulation bearing polynucleotide sequences corresponding to appropriate protein molecules which, when combined with appropriate control sequences, confer specific properties on the host cell to be transformed. Plasmids, viruses, and bacteriophage are suitable vectors, since they are replicons in their own right. Artificial vectors are constructed by cutting and joining DNA molecules from different sources using restriction enzymes and ligases. Vectors include Recombinant DNA cloning vectors and Recombinant DNA expression vectors.
X-gal--an abbreviation for 5-bromo-4-chloro-3-idolyl beta-D-galactoside.
SEQ ID NO: 1 refers to the sequence set forth in the sequence listing and means an anti-obesity protein of the formula: ##STR3## wherein: Xaa at position 4 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 7 of SEQ ID NO:. 1 is Gln or Glu;
Xaa at position 22 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 27 of SEQ ID NO: 1 is Thr or Ala;
Xaa at position 28 of SEQ ID NO: 1 is Gln, Glu or absent;
Xaa at position 34 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 54 of SEQ ID NO: 1 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, or Gly;
Xaa at position 56 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 62 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 63 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 68 of SEQ ID NO: 1 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, or Gly;
Xaa at position 72 of SEQ ID NO: 1 is Gln, Asn, or Asp;
Xaa at position 75 of SEQ ID NO: 1 is Gln or Glu;
Xaa at position 78 of SEQ ID NO: 1 is Gln, Ash, or Asp;
Xaa at position 82 of SEQ ID NO: 1 is Gln, Asn, or Asp;
and
Xaa at position 100 of SEQ ID NO: 1 is Gin, Trp, Tyr, Phe, Ile, Val, or Leu.
SEQ ID NO: 2 refers to the sequence set forth in the sequence listing and means an anti-obesity protein of the formula: ##STR4## wherein: Xaa at position 8 of SEQ ID NO: 2 is Asp or Glu;
Xaa at position 30 of SEQ ID NO: 2 is Gln or Glu;
Xaa at position 34 of SEQ ID NO: 2 is Gln or Glu;
Xaa at position 36 of SEQ ID NO: 2 is Met, methionine sulfoxide, Let, Ile, Val, Ala, or Gly;
Xaa at position 38 of SEQ ID NO: 2 is Gln, Trp, Tyr, Phe, Ile, Val, or Let; and
Xaa at position 39 of SEQ ID NO: 2 is Gln or Glu.
Yiying Zhang et al. in Nature 7: 425-32 (December 1994) report the cloning of the murine obese (ob) mouse gene and present mouse DNA and the naturally occurring amino acid sequence of the obesity protein for the mouse and human. This protein is speculated to be a hormone that is secreted by fat cells and controls body weight.
The present invention provides biologically active proteins that provide effective treatment for obesity. Many of the claimed proteins offer additional advantages of better absorption characteristics allowing administration nasally, bronchally, transdermally, or parentally. In addition, the claimed proteins improve in vivo stability or increased biological half-life.
The claimed proteins ordinarily are prepared by modification of the DNA encoding the claimed protein and thereafter expressing the DNA in recombinant cell culture. Techniques for making substitutional mutations at predetermined sites in DNA having a known sequence are well known, for example M13 primer mutagenesis. The mutations that might be made in the DNA encoding the present anti-obesity proteins must not place the sequence out of reading frame and preferably will not create complementary regions that could produce secondary mRNA structure. See DeBoer et al., EP 75,444A (1983).
The compounds of the present invention may be produced either by recombinant DNA technology or well known chemical procedures, such as solution or solid-phase peptide synthesis, or semi-synthesis in solution beginning with protein fragments coupled through conventional solution methods.
A. Solid Phase
The synthesis of the claimed protein may proceed by solid phase peptide synthesis or by recombinant methods. The principles of solid phase chemical synthesis of polypeptides are well known in the art: and may be found in general texts in the area such as Dugas, H. and Penney, C., Bioorganic Chemistry Springer-Verlag, New York, pgs. 54-92 (1981). For example, peptides may be synthesized by solid-phase methodology utilizing an PE-Applied Biosystems 430A peptide synthesizer (commercially available from Applied Biosystems, Foster City California) and synthesis cycles supplied by Applied Biosystems. Boc amino acids and other reagents are commercially available from PE-Applied Biosystems and other chemical supply houses. Sequential Boc chemistry using double couple protocols are applied to the starting p-methyl benzhydryl amine resins for the production of C-terminal carboxamides. For the production of C-terminal acids, the corresponding PAM resin is used. Arginine, Asparagine, Glutamine, Histidine and Methionine are coupled using preformed hydroxy benzotriazole esters. The following side chain protection may be used:
Arg, Tosyl
Asp, cyclohexyl or benzyl
Cys, 4-methylbenzyl
Glu, cyclohexyl
His, benzyloxymethyl
Lys, 2-chlorobenzyloxycarbonyl
Met, sulfoxide
Ser, Benzyl
Thr, Benzyl
Trp, formyl
Tyr, 4-bromo carbobenzoxy Boc deprotection may be accomplished with trifluoroacetic acid (TFA) in methylene chloride. Formyl removal from Trp is accomplished by treatment of the peptidyl resin with 20% piperidine in dimethytlformamide for 60 minutes at 4° C. Met(O) can be reduced by treatment of the peptidyl resin with TFA/dimethylsulfide/conHCl (95/5/1) at 25° C. for 60 minutes. Following the above pre-treatments, the peptides may be further deprotected and cleaved from the resin with anhydrous hydrogen fluoride containing a mixture of 10% m-cresol or m-cresol/10% p-thiocresol or m-cresol/p-thiocresol/dimethylsulfide. Cleavage of the side chain protecting group(s) and of the peptide from the resin is carried out at zero degrees Centigrade or below, preferably -20° C. for thirty minutes followed by thirty minutes at 0° C. After removal of the HF, the peptide/resin is washed with ether. The peptide is extracted with glacial acetic acid and lyophilized. Purification is accomplished by reverse-phase C18 chromatography (Vydac) column in 0.1% TFA with a gradient of increasing acetonitrile concentration.
One skilled in the art recognizes that the solid phase synthesis could also be accomplished using the FMOC strategy and a TFA/scavenger cleavage mixture.
B. Recombinant Synthesis
The claimed proteins may also be produced by recombinant methods. Recombinant methods are preferred if a high yield is desired. The basic steps in the recombinant production of protein include:
a) construction of a synthetic or semi-synthetic (or isolation from natural sources) DNA encoding the claimed protein,
b) integrating the coding sequence into an expression vector in a manner suitable for the expression of the protein either alone or as a fusion protein,
c) transforming an appropriate eukaryotic or prokaryotic host cell with the expression vector, and
d) recovering and purifying the recombinantly produced protein.
2. a. Gene Construction
Synthetic genes, the in vitro or in vivo transcription and translation of which will result. in the production of the protein may be constructed by techniques well known in the art. Owing to the natural degeneracy of the genetic code, the skilled artisan will recognize that a sizable yet definite number of DNA sequences may be constructed which encode the claimed proteins. In the preferred practice of the invention, synthesis is achieved by recombinant DNA technology.
Methodology of synthetic gene construction is well known in the art. For example, see Brown, et al. (1979) Methods in Enzymology, Academic Press, N.Y., Vol. 68, pgs. 109-151. The DNA sequence corresponding to the synthetic claimed protein gene may be generated using conventional DNA synthesizing apparatus such as the Applied Biosystems Model 280A or 380B DNA synthesizers (commercially available from Applied Biosystems, Inc., 850 Lincoln Center Drive, Foster City, Calf. 94404).
It may desirable in some applications to modify the coding sequence of the claimed protein so as to incorporate a convenient protease sensitive cleavage site, e.g., between the signal peptide and the structural protein facilitating the controlled excision of the signal peptide from the fusion protein construct.
The gene encoding the claimed protein may also be created by using polymerase chain reaction (PCR). The template can be a cDNA library (commercially available from CLONETECH or STRATAGENE) or mRNA isolated from human adipose tissue. Such methodologies are well known in the art Maniatis, et al. Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Press, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. (1989).
2. b. Direct expression or Fusion protein
The claimed protein may be made either by direct expression or as fusion protein comprising the claimed protein followed by enzymatic or chemical cleavage. A variety of peptidases (e.g. trypsin) which cleave a polypeptide at specific sites or digest the peptides from the amino or carboxy termini (e.g. diaminopeptidase) of the peptide chain are known. Furthermore, particular chemicals (e.g. cyanogen bromide) will cleave a polypeptide chain at specific sites. The skilled artisan will appreciate the modifications necessary to the amino acid sequence (and synthetic or semi-synthetic coding sequence if recombinant means are employed) to incorporate site-specific internal cleavage sites. see e.g., Carter P., Site Specific Proteolysis of Fusion Proteins, Ch. 13 in Protein Purification: From Molecular Mechanisms to Large Scale Processes, American Chemical Soc., Washington, D.C. (1990).
2. c. Vector Construction
construction of suitable vectors containing the desired coding and control sequences employ standard ligation techniques. Isolated plasmids or DNA fragments are cleaved, tailored, and religated in the form desired to form the plasmids required.
To effect the translation of the desired protein, one inserts the engineered synthetic DNA sequence in any of a plethora of appropriate recombinant DNA expression vectors through the use of appropriate restriction endonucleases. The claimed protein is a relatively large protein. A synthetic coding sequence is designed to possess restriction endonuclease cleavage sites at either end of the transcript to facilitate isolation from and integration into these expression and amplification and expression plasmids. The isolated cDNA coding sequence may be readily modified by the use of synthetic linkers to facilitate the incorporation of this sequence into the desired cloning vectors by techniques well known in the art. The particular endonucleases employed will be dictated by the restriction endonuclease cleavage pattern of the parent expression vector to be employed. The choice of restriction sites are chosen so as to properly orient the coding sequence with control sequences to achieve proper in-frame reading and expression of the claimed protein.
In general, plasmid vectors containing promoters and control sequences which are derived from species compatible with the host cell are used with these hosts. The vector ordinarily carries a replication site as well as marker sequences which are capable of providing phenotypic selection in transformed cells. For example, E. coli is typically transformed using pBR322, a plasmid derived from an E. coli species (Bolivar, et al., Gene 2: 95 (1977)). Plasmid pBR322 contains genes for ampicillin and tetracycline resistance and thus provides easy means for identifying transformed cells. The pBR322 plasmid, or other microbial plasmid must also contain or be modified to contain promoters and other control elements commonly used in recombinant DNA technology.
The desired coding sequence is inserted into an expression vector in the proper orientation to be transcribed from a promoter and ribosome binding site, both of which should be functional in the host cell in which the protein is to be expressed. An example of such an expression vector is a plasmid described in Belagaje et al., U.S. Pat. No. 5,304,493, the teachings of which are herein incorporated by reference. The gene encoding A-C-B proinsulin described in U.S. Pat. No. 5,304,493 can be removed from the plasmid pRB182 with restriction enzymes NdeI and BamHI. The genes encoding the protein of the present invention can be inserted into the plasmid backbone on a NdeI/BamHI restriction fragment cassette.
2.d. Procaryotic expression
In general, procaryotes are used for cloning of DNA sequences in constructing the vectors useful in the invention. For example, E. coli K12 strain 294 (ATCC No. 31446) is particularly useful. Other microbial strains which may be used include E. coli B and E. coli X1776 (ATCC No. 31537). These examples are illustrative rather than limiting.
Prokaryotes also are used for expression. The aforementioned strains, as well as E. coli W3110 (prototrophic, ATCC No. 27325), bacilli such as Bacillus subtills, and other enterobacteriaceae such as Salmonella typhimurium or Serratia marcescans, and various pseudomonas species may be used. promote suitable for use with prokaryotic hosts include the β-lactamase (vector pGX2907 [ATCC 39344] contains the replicon and β-lactamase gene) and lactose promoter systems (Chang et al., Nature, 275:615 (1978); and Goeddel et al., Nature 281:544 (1979)), alkaline phosphatase, the tryptophan (trp) promoter system (vector pATH1 [ATCC 37695] is designed to facilitate expression of an open reading frame as a trpE fusion protein under control of the trp promoter) and hybrid promoters such as the tac promoter (isolatable from plasmid pDR540 ATCC-37282). However, other functional bacterial promoters, whose nucleotide sequences are generally known, enable one of skill in the art to ligate them to DNA encoding the protein using linkers or adaptors to supply any required restriction sites. Promoters for use in bacterial systems also will contain a Shine-Dalgarno sequence operably linked to the DNA encoding protein.
2. e. Eucaryotic expression
The protein may be recombinantly produced in eukaryotic expression systems. Preferred promoters controlling transcription in mammalian host cells may be obtained from various sources, for example, the genomes of viruses such as: polyoma, Simian Virus 40 (SV40), adenovirus, retroviruses, hepatitis-B virus and most preferably cytomegalovirus, or from heterologous mammalian promoters, e.g. β-actin promoter. The early and late promoters of the SV40 virus are conveniently obtained as an SV40 restriction fragment which also contains the SV40 viral origin of replication. Fiers, et al., Nature, 273:113 (1978). The entire SV40 genome may be obtained from plasmid pBRSV, ATCC 45019. The immediate early promoter of the human cytomegalovirus may be obtained from plasmid pCMBβ (ATCC 77177). Of course, promoters from the host cell or related species also are useful herein.
Transcription of a DNA encoding the claimed protein by higher eukaryotes is increased by inserting an enhancer sequence into the vector. Enhancers are cis-acting elements of DNA, usually about 10-300 bp, that act on a promoter to increase its transcription. Enhancers are relatively orientation and position independent having been found 5' (Laimins, L. et al., PNAS 75:993 (1981)) and 3' (Lusky, M. L., et al., Mol. Cell Bio. 3:1108 (1983)) to the transcription unit, within an intron (Banerji, J. L. et al., Cell 33:729 (1983)) as well as within the coding sequence itself (Osborne, T. F., et al., MOl. Cell Bio, 4:1293 (1984)). Many enhancer sequences are now known from mammalian genes (globin, RSV, SV40, EMC, elastase, albumin, a-fetoprotein and insulin). Typically, however, one will use an enhancer from a eukaryotic cell virus. Examples include the SV40 late enhancer, the cytomegalovirus early promoter enhancer, the polyoma enhancer on the late side of the replication origin, and adenovirus enhancers.
Expression vectors used in. eukaryotic host cells (yeast, fungi, insect, plant, animal, human or nucleated cells from other multicellular organisms) will also contain sequences necessary for the termination of transcription which may affect mRNA expression. These regions are transcribed as polyadenylated segments in the untranslated portion of the mRNA encoding protein. The 3' untranslated regions also include transcription termination sites.
Expression vectors may contain a selection gene, also termed a selectable marker. Examples of suitable selectable markers for mammalian cells are dihydrofolate reductase (DHFR, which may be derived from the BglII/HindIII restriction fragment of pJOD-10 [ATCC 68815]), thymidine kinase (herpes simplex virus thymidine kinase is contained on the BamHI fragment of vP-5 clone [ATCC 2028]) or neomycin (G418) resistance genes (obtainable from pNN414 yeast artificial chromosome vector [ATCC 37682]). When such selectable markers are successfully transferred into a mammalian host cell, the transfected mammalian host cell can survive if placed under selective pressure. There are two widely used distinct categories of selective regimes. The first category is based on a cell's metabolism and the use of a mutant cell line which lacks the ability to grow without a supplemented media. Two examples are: CHO DHFR- cells (ATCC CRL-9096) and mouse LTK- cells (L-M(TK-) ATCC CCL-2.3). These cells lack the ability to grow without the addition of such nutrients as thymidine or hypoxanthine. Because these cells lack certain genes necessary for a complete nucleotide synthesis pathway, they cannot survive unless the missing nucleotides are provided in a supplemented media. An alternative to supplementing the media is to introduce an intact DHFR or TK gene into cells lacking the respective genes, thus altering their growth requirements. Individual cells which were not transformed with the DHFR or TK gene will not be capable of survival in nonsupplemented media.
The second category is dominant selection which refers to a selection scheme used in any cell type and does not require the use of a mutant cell line. These schemes typically use a drug to arrest growth of a host cell. Those cells which have a novel gene would express a protein conveying drug resistance and would survive the selection. Examples of such dominant selection use the drugs neomycin, Southern P. and Berg, P., J. Molec. Appl. Genet. 327 (1982), mycophenolic acid, Mulligan, R. C. and Berg, P. Science 209:1422 (1980), or hygromycin, Sugden, B. et al., Mol Cell. Biol. 5:410-413 (1985). The three examples given above employ bacterial genes under eukaryotic control to convey resistance to the appropriate drug G418 or neomycin (geneticin), xgpt (mycophenolic acid) or hygromycin, respectively.
A preferred vector for eucaryotic expression is pRc/CMV. pRc/CMV is commercially available from Invitrogen Corporation, 3985 Sorrento Valley Blvd., San Diego, Calif. 92121. To confirm correct sequences in plasmids constructed, the ligation mixtures are used to transform E. coli K12 strain DH5a (ATCC 31446) and successful transformants selected by antibiotic resistance where appropriate. Plasmids from the transformants are prepared, analyzed by restriction and/or sequence by the method of Messing, et al., Nucleic Acids Res. 9:309 (1981).
Host cells may be transformed with the expression vectors of this invention and cultured in conventional nutrient media modified as is appropriate for inducing promoters, selecting transformants or amplifying genes. The culture conditions, such as temperature, pH and the like, are those previously used with the host cell selected for expression, and will be apparent to the ordinarily skilled artisan. The techniques of transforming cells with the aforementioned vectors are well known in the art and may be found in such general references as Maniatis, et al., Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Press, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. (1989), or Current Protocols in Molecular Biology (1989) and supplements.
Preferred suitable host cells for expressing the vectors encoding the claimed proteins in higher eukaryotes include: African green monkey kidney line cell line transformed by SV40 (COS-7, ATCC CRL-1651); transformed human primary embryonal kidney cell line 293, (Graham, F. L. et al., J. Gen Virol. 36:59-72 (1977), Virology 77:319-329, Virology 86:10-21); baby hamster kidney cells (BHK-21(C-13), ATCC CCL-10, Virology 16:147 (1962)); chinese hamster ovary cells CHO-DHFR (ATCC CRL-9096), mouse Sertoli cells (TM4, ATCC CRL-1715, Biol. Reprod. 23:243-250 (1980)); african green monkey kidney cells (VERO 76, ATCC CRL-1587); human cervical epitheloid carcinoma cells (HeLa, ATCC CCL-2); canine kidney cells (MDCK, ATCC CCL-34); buffalo rat liver cells (BRL 3A, ATCC CRL-1442); human diploid lung cells (WI-38, ATCC CCL-75); human hepatocellular carcinoma cells (Hep G2, ATCC HB-8065);and mouse mammary tumor cells (MMT 060562, ATCC CCL51).
2. f. Yeast expression
In addition to prokaryotes, eukaryotic microbes such as yeast cultures may also be used. Saccharomyces cerevisiae, or common baker's yeast is the most commonly used eukaryotic microorganism, although a number of other strains are commonly available. For expression in Saccharomyces, the plasmid YRp7, for example, (ATCC-40053, Stinchcomb, et al., Nature 282:39 (1979); Kingsman et al., Gene 7:141 (1979); Tschemper et al., Gene 10:157 (1980)) is commonly used. This plasmid already contains the trp gene which provides a selection marker for a mutant strain of yeast lacking the ability to grow in tryptophan, for example ATCC no. 44076 or PEP4-1 (Jones, Genetics 85:12 (1977)).
Suitable promoting sequences for use with yeast hosts include the promoters for 3-phosphoglycerate kinase (found on plasmid pAP12BD ATCC 53231 and described in U.S. Pat. No. 4,935,350, Jun. 19, 1990) or other glycolytic enzymes such as enolase (found on plasmid pAC1 ATCC 39532), glyceraldehyde-3-phosphate dehydrogenase (derived from plasmid pHcGAPC1 ATCC 57090, 57091), zymomonas mobilis (U.S. Pat. No. 5,000,000 issued Mar. 19, 1991), hexokinase, pyruvate decarboxylase, phosphofructokinase, glucose-6-phosphate isomerase, 3-phosphoglycerate mutase, pyruvate kinase, triosephosphate isomerase, phosphoglucose isomerase, and glucokinase.
Other yeast promoters, which are inducible promoters having the additional advantage of transcription controlled by growth conditions, are the promoter regions for alcohol dehydrogenase 2, isocytochrome C, acid phosphatase, degradative enzymes associated with nitrogen metabolism, metallothionein (contained on plasmid vector pCL28XhoLHBPV ATCC 39475, U.S. Pat. No. 4,840,896), glyceraldehyde 3-phosphate dehydrogenase, and enzymes responsible for maltose and galactose (GALl found on plasmid pRY121 ATCC 37658) utilization. Suitable vectors and promoters for use in yeast expression are further described in R. Hitzeman et al., European Patent Publication No. 73,657A. Yeast enhancers such as the UAS Gal from Saccharomyces cerevisiae (found in conjunction with the CYC1 promoter on plasmid YEpsec-hI1beta ATCC 67024), also are advantageously used with yeast promoters.
The following examples are presented to further illustrate the preparation of the claimed proteins. The scope of the present invention is not to be construed as merely consisting of the following examples.
EXAMPLE 1
A DNA sequence encoding the following protein sequence: ##STR5## is obtained using standard PCR methodology. A forward primer (5'-GG GG CAT ATG AGG GTA CCT ATC CAG AAA GTC CAG GAT GAC AC) SEQ ID NO: 3 and a reverse primer (5'-GG GG GGATC CTA TTA GCA CCC GGG AGA CAG GTC CAG CTG CCA CAA CAT) SEQ ID NO: 4 is used to amplify sequences from a human fat cell library (commercially available from CLONETECH). The PCR product is cloned into PCR-Script (available from STRATAGENE) and sequenced.
EXAMPLE 2
Vector Construction
A plasmid containing the DNA sequence encoding the desired claimed protein is constructed to include NdeI and BaHI restriction sites. The plasmid carrying the cloned PCR product is digested with NdeI and BamHI restriction enzymes. The small ˜450bp fragment is gel-purified and ligated into the vector pRB182 from which the coding sequence for A-C-B proinsulin is deleted. The ligation products are transformed into E. coli DH10B (commercially available from GIBCO-BRL) and colonies growing on tryptone-yeast (DIFCO) plates supplemented with 10 μg/mL of tetracycline are analyzed. Plasmid DNA is isolated, digested with NdeI and B 3BamHI and the resulting fragments are separated by agarose gel electrophoresis. Plasmids containing the expected ˜450bp NdeI to BamHI fragment are kept. E. coli B BL21 (DE3) (commercially available from NOVOGEN) are transformed with this second plasmid expression suitable for culture for protein production.
The techniques of transforming cells with the aforementioned vectors are well known in the art and may be found in such general references as Maniatis, et al. (1988) Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Press, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. or Current Protocols in Molecular Biology (1989) and supplements. The techniques involved in the transformation of E. coli cells used in the preferred practice of the invention as exemplified herein are well known in the art. The precise conditions under which the transformed E. coli cells are cultured is dependent on the nature of the E. coli host cell line and the expression or cloning vectors employed. For example, vectors which incorporate thermoinducible promoter-operator regions, such as the c1857 thermoinducible lambda-phage promoter-operator region, require a temperature shift from about 30 to about 40 degrees C. in the culture conditions so as to induce protein synthesis.
In the preferred embodiment of the invention E. coli K12 RV308 cells are employed as host cells but numerous other cell lines are available such as, but not limited to, E. coli K12 L201, L687, L693, L507, L640, L641, L695, L814 (E. coli B). The transformed host cells are then plated on appropriate media under the selective pressure of the antibiotic corresponding to the resistance gene present on the expression plasmid. The cultures are then incubated for a time and temperature appropriate to the host cell line employed.
Proteins which are expressed in high-level bacterial expression systems characteristically aggregate in granules or inclusion bodies which contain high levels of the overexpressed protein. Kreuger et al., in Protein Folding, Gierasch and King, eds., pgs 136-142 (1990), American Association for the Advancement of Science Publication No. 89-18S, Washington, D.C. Such protein aggregates must be solubilized to provide further purification and isolation of the desired protein product. Id. A variety of techniques using strongly denaturing solutions such as guanidinium-HCl1 and/or weakly denaturing solutions such as dithiothreitol (DTT) are used to solubilize the proteins.
Gradual removal of the denaturing agents (often by dialysis) in a solution allows the denatured protein to assume its native conformation. The particular conditions for denaturation and folding are determined by the particular protein expression system and/or the protein in question.
Preferably, the present proteins are expressed as Met-Arg-Seq ID NO: 1 so that the expressed proteins may be readily converted to the claimed protein with Cathepsin C. The purification of proteins is by techniques known in the art and includes reverse phase chromatography, affinity chromatography, and size exclusion.
The claimed proteins may exist, particularly when formulated, as dimers, trimers, tetramers, and other multimers. Such multimers are included within the scope of the present invention.
The present invention provides a method for treating obesity. The method comprises administering to the organism an effective amount of anti-obesity protein in a dose between about 1 and 1000 μg/kg. A preferred dose is from about 10 to 100 μg/kg of active compound. A typical daily dose for an adult human is from about 0.5 to 100 mg. In practicing this method, compounds of the Formula (I) can be administered in a single daily dose or in multiple doses per day. The treatment regime may require administration over extended periods of time. The amount per administered dose or the total amount administered will be determined by the physician and depend on such factors as the nature and severity of the disease, the age and general health of the patient and the tolerance of the patient to the compound.
The instant invention further provides pharmaceutical formulations comprising compounds of the Formula (I). The proteins, preferably in the form of a pharmaceutically acceptable salt, can be formulated for nasal, bronchal, transdermal, or parenteral administration for the therapeutic or prophylactic treatment of obesity. For example, compounds of the Formula (I) can be admixed with conventional pharmaceutical carriers and excipients. The compositions comprising claimed proteins contain from about 0.1 to 90% by weight of the active protein, preferably in a soluble form, and more generally from about 10 to 30%.
For intravenous (IV) use, the protein is administered in commonly used intravenous fluid(s)and administered by infusion. Such fluids, for example, physiological saline, Ringer's solution or 5% dextrose solution can be used.
For intramuscular preparations, a sterile formulation, preferably a suitable soluble salt form of a protein of the Formula (I), for example the hydrochloride salt, can be dissolved and administered in a pharmaceutical diluent such as pyrogen-free water (distilled), physiological saline or 5% glucose solution. A suitable insoluble form of the compound may be prepared and administered as a suspension in an aqueous base or a pharmaceutically acceptable oil base, e.g. an ester of a long chain fatty acid such as ethyl oleate. It may also be desirable to administer the compounds. of Formula (I) intranasally. Formulations useful in the intranasal absorption of proteins are well known in the art. Nasal formulations comprise the protein and carboxyvinyl polymer preferably selected from the group comprising the acrylic acid series hydrophilic crosslinked polymer, e.g. carbopole 934, 940, 941 (Goodrich Co.). The polymer accelerates absorption of the protein, and gives suitable viscosity to prevent discharge from nose. Suitable content of the polymer is 0.05-2 weight %. By neutralisation of the polymer with basic substance, thickening effect is increased. The amount of active compound is commonly 0.1-10%. The nasal preparation may be in drop form, spraying applicator or aerosol form.
The ability of the present compounds to treat obesity is demonstrated in vivo as follows:
Biological Testing for Amti-obesity proteins
Parabiotic experiments suggest that a protein is released by peripheral adipose tissue and that the protein is able to control body weight gain in normal, as well as obese mice. Therefore, the most closely related biological test is to inject the test article by any of several routes of administration (e.g. i.v., s.c., i.p., or by minipump or cannula) and then to monitor food and water consumption, body weight gain, plasma chemistry or hormones (glucose, insulin, ACTH, corticosterone, GH, T4) over various time periods.
Suitable test animals include normal mice (ICR, etc.) and obese mice (ob/ob, Avy/a, KK-Ay, tubby, fat). The ob/ob mouse model of obesity and diabetes is generally accepted in the art as being indicative of the obesity condition. Controls for non-specific effects for these injections are done using vehicle with or without the active agent of similar composition in the same animal monitoring the same parameters or the active agent itself in animals that are thought to lack the receptor (db/db mice, fa/fa or cp/cp rats). Proteins demonstrating activity in these models will demonstrate similar activity in other mammals, particularly humans.
Since the target tissue is expected to be the hypothalamus where food intake and lipogenic state are regulated, a similar model is to inject the test article directly into the brain (e.g.i.c.v. injection via lateral or third ventricles, or directly into specific hypothalamic nuclei (e.g. arcuate, paraventricular, perifornical nuclei). The same parameters as above could be measured, or the release of neurotransmitters that are known to regulate feeding or metabolism could be monitored (e.g. NPY, galanin, norepinephrine, dopamine, β-endorphin release).
Similar studies are accomplished in vitro using isolated hypothalamic tissue in a perifusion or tissue bath system. In this situation, the release of neurotransmitters or electrophysiological changes is monitored.
The compounds are active in at least one of the above biological tests and are anti-obesity agents. As such, they are useful in treating obesity and those disorders implicated by obesity. However, the proteins are not only useful as therapeutic agents; one skilled in the art recognizes that the proteins are useful in the production of antibodies for diagnostic use and, as proteins, are useful as feed additives for animals. Furthermore, the compounds are useful for controlling weight for cosmetic purposes in mammals. A cosmetic purpose seeks to control the weight of a mammal to improve bodily appearance. The mammal is not necessarily obese. Such cosmetic use forms part of the present invention.
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 4(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 100 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 4(D) OTHER INFORMATION: /note="Xaa at position 4 of SEQ ID NO:1 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 7(D) OTHER INFORMATION: /note="Xaa at position 7 of SEQ ID NO:1 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 22(D) OTHER INFORMATION: /note="Xaa at position 22 of SEQ IDNO:1 is Gln, Asn or Asp;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 27(D) OTHER INFORMATION: /note="Xaa at position 27 of SEQ IDNO:1 is Thr or Ala;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 28(D) OTHER INFORMATION: /note="Xaa at position 28 of SEQ IDNO:1 is Gln, Glu or absent;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 34(D) OTHER INFORMATION: /note="Xaa at position 34 of SEQ IDNO:1 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 54(D) OTHER INFORMATION: /note="Xaa at position 54 of SEQ IDNO:1 is Met, methionine sulfoxide, Leu, Ile, Val, Ala, orGly;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 56(D) OTHER INFORMATION: /note="Xaa at position 56 of SEQ IDNO:1 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 62(D) OTHER INFORMATION: /note="Xaa at position 62 of SEQ IDNO:1 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 63(D) OTHER INFORMATION: /note="Xaa at position 63 of SEQ IDNO:1 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 68(D) OTHER INFORMATION: /note="Xaa at position 68 of SEQ IDNO:1 is Met, methionine sulfoxide, Leu, Ile, Val, Ala orGly;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 72(D) OTHER INFORMATION: /note="Xaa at position 72 of SEQ IDNO:1 is Gln, Asn or Asp;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 75(D) OTHER INFORMATION: /note="Xaa at position 75 of SEQ IDNO:1 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 78(D) OTHER INFORMATION: /note="Xaa at position 78 of SEQ IDNO:1 is Gln, Asn or Asp;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 82(D) OTHER INFORMATION: /note="Xaa at position 82 of SEQ IDNO:1 is Gln, Asn or Asp;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 100(D) OTHER INFORMATION: /note="Xaa at position 100 of SEQ IDNO:1 is Gln, Trp, Tyr, Phe, Ile, Val or Leu."(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:ValProIleXaaLysValXaaAspAspThrLysThrLeuIleLysThr151015IleValThrArgIleXaaAspIleSerHisXaaXaaSerValSerSer202530LysXaaLysValThrGlyLeuAspPheIleProGlyLeuHisProIle354045LeuThrLeuSerLysXaaAspXaaThrLeuAlaValTyrXaaXaaIle505560LeuThrSerXaaProSerArgXaaValIleXaaIleSerXaaAspLeu65707580GluXaaLeuArgAspLeuLeuHisValLeuAlaPheSerLysSerCys859095HisLeuProXaa100(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 46 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 8(D) OTHER INFORMATION: /note="Xaa at position 8 of SEQ ID NO:2 is Asp or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 30(D) OTHER INFORMATION: /note="Xaa at position 30 of SEQ IDNO:2 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 34(D) OTHER INFORMATION: /note="Xaa at position 34 of SEQ IDNO:2 is Gln or Glu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 36(D) OTHER INFORMATION: /note="Xaa at position 36 of SEQ IDNO:2 is Met, methionine sulfoxide, Leu, Ile, Val, Ala orGly;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 38(D) OTHER INFORMATION: /note="Xaa at position 38 of SEQ IDNO:2 is Gln, Trp, Tyr, Phe, Ile, Val, or Leu;"(ix) FEATURE:(A) NAME/KEY: Modified-site(B) LOCATION: 39(D) OTHER INFORMATION: /note="Xaa at position 39 of SEQ IDNO:2 is Gln or Glu."(xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:AlaSerGlyLeuGluThrLeuXaaSerLeuGlyGlyValLeuGluAla151015SerGlyTyrSerThrGluValValAlaLeuSerArgLeuXaaGlySer202530LeuXaaAspXaaLeuXaaXaaLeuAspLeuSerProGlyCys354045(2) INFORMATION FOR SEQ ID NO:3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 42 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:GGGGCATATGAGGGTACCTATCCAGAAAGTCCAGGATGACAC42(2) INFORMATION FOR SEQ ID NO:4:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 48 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:GGGGGGATCCTATTAGCACCCGGGAGACAGGTCCAGCTGCCACAACAT48__________________________________________________________________________ | The present invention provides anti-obesity proteins, which when administered to a patient regulate fat tissue. Accordingly, such agents allow patients to overcome their obesity handicap and live normal lives with much reduced risk for type II diabetes, cardiovascular disease and cancer. | 2 |
[0001] This is a continuation-in-part application of international application PCT/EP00/09008 filed Sep. 15, 2000 and claiming the priority of German application 199 49 738.9 filed Oct. 15, 1999.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a method for producing surface acoustic wave sensors on the basis of surface acoustic wave components and to a surface acoustic wave sensor.
[0003] The use of surface acoustic wave components as gas sensors was originally proposed by Wohltjen who examined this measuring technique since 1979 (Wohltjen, H., Dessey, R.: Surface acoustic wave probe for chemical analysis”; Anal. Chem. 51 (1979) 1458-1464). These Surface Wave (OFW) building elements which were actually developed as miniaturized high frequency filters find increasingly interest for use as chemical and biochemical sensors (Rapp, M.; Barie, N.; Stier, S.; Ache, H. J.; “Optimization of an analytical SAW microsystem for organic gas detection”; Proc. IEEE Ultrasonic. Symp. (1995) 477-480). As sensor property, the mass-sensitive behavior of such components is utilized by applying a coating which is selective for the material to be sensed and the component is the frequency determining element of an oscillator resonant circuit.
[0004] In a surface wave component, interdigital transducers are disposed on the piezo-electric substrate of the building component. By the application of a high frequency AC voltage, the transmitter transducer is caused to vibrate. The surface wave generated thereby moves over the substrate and is converted, by the piezo effect, in the receiver transducer into an electrical alternating field. By way of an amplifier, which compensates for the losses resulting from the attenuation of the acoustic wave, the electrical signal is again fed into the transmitter transducers. In this way, an oscillation with a specific resonance frequency, which is based on the travel time of the acoustic and electric wave, occurs in the oscillation circuit. This frequency is uncoupled from the circuit as a measuring signal.
[0005] The propagation velocity of the surface wave depends on the character of the surface. If the piezo electric substrate is provided with a thin selective coating the acoustic velocity is changed and, as a result, the resonance frequency of the oscillator circuit is changed.
[0006] If an analyte sample is applied to the coated component, a sorption of the analyte occurs in the layer whereby the mass of the building component is increased. As a result, the acoustic velocity is again changed which results in a measurable change of the oscillation frequency. Since frequencies can be measured very accurately, already very small changes of the mass charge of the surface wave building component can be detected.
[0007] During the coating of the surface wave sensor with a viscous sorption polymer, the cross-linkages of the sensor surface are often destroyed by the sorption polymer. This results in a non-uniform sorption polymer layer on the substrate and, because of an excessive attenuation caused thereby, in a drastic deterioration of the sensor sensitivity.
[0008] It is the object of the present invention to provide a method, which permits the manufacture of a homogeneous sorption polymer layer and a sensor with a homogeneous sorption polymer layer.
SUMMARY OF THE INVENTION
[0009] In a method for producing a surface wave sensor on the basis of a surface wave building component a polymer parylene film with a thickness of 20 to 200 nm is applied to a hydrophilic sensor surface of the surface wave building component by deposition from the gas phase, whereby the hydrophilic sensor surface becomes hydrophobic, the surface is then subjected to plasma activation to render it hydrophilic and a hydrophilic sorption polymer layer is then applied to the parylene film by spray coating or drip coating.
[0010] The invention has the following advantages:
[0011] Because of the better wetting of the sensor surface by the sorption polymers, less complicated coating techniques such as drip coating can be utilized. The improved wetting results in a more uniform deposition of the sorption polymer and, consequently, in a lower attenuation than can be obtained with a non-uniform layer of the same amount of the same polymer. The sensitivity of the sensor can therefore be increased by increasing the layer thickness of the sorption polymer up to a critical attenuation. With the improved wetting also the aging behavior of the sensor is positively affected.
[0012] Below, the invention will be described in greater detail on the basis of examples with reference to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 shows the wetting properties of a sensor coated with parylene and of an uncoated sensor.
[0014] [0014]FIGS. 2 and 3 show phase curves of sensors with two different sorption polymer layers with, and without, an intermediate parylene layer.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0015] With the deposition of a parylene film with a thickness of about 20-50 nm on the OFW surface, a polymer interface layer is formed for the adaptation of the surface tension to the sorption polymer (generally hydrophobic) to be deposited with little increased attenuation (about 1 dB with a 50 nm layer thickness) of the OFW-component. For improving the wetting of polar and, consequently, hydrophilic sorption polymers, the interface layer can be made hydrophilic by a short plasma treatment (<5 min.). Since the plasma treatment is effective only at the surface of the polymer film, the hydrophobic barrier properties thereof remain effective.
[0016] With the use of the parylene film with a thickness of between 50 and 200 nm, the use of acid/aggressive polymer has become possible, which, as a result of the barrier properties of the parylene, can no longer corrode the sensor surface or, respectively, the interdigital transducer necessary for the in-coupling and out-coupling of the energy.
[0017] Hydrophilic sorption polymers are for example polyisobutylene, polydimethylsiloxane or phenylmethylsiloxane and hydrophilic sorption polymers are for example PEG (PolyEthyleneGlycol) or PVA (PolyVinylAlcohol).
[0018] With the use of non-corrosive sorption polymers or when measuring in inert media, the thickness of the parylene layer may be between 20 and 30 nm.
[0019] The use of parylene as coating material fulfills two particular purposes:
[0020] A thin, uniform polymer film with a low surface tension forms an adhesion improving intermediate layer between the substrate and the sorption polymers and prevents the destruction of cross-links.
[0021] Because of its barrier properties, the parylene film protects the OFW component from corrosive effects of acidic and basic sorption polymers or aggressive analytes, or respectively, atmospheres.
[0022] Parylenes form a family of linear partially crystalline not cross-linked polymers with interesting properties and various utilization possibilities.
[0023] The most simple representative, parylene N (p-xylylene), consists of a linear polymer chain with 1.4-ethylene-bridged phenyl rings.
[0024] Besides the parylene N also the chlorinated variants parylene C and parylene D have wide industrial applications because of their lower permeability.
[0025] For the coating of thin substrates with thin films of parylenes special vacuum apparatus are required. They consist of three subsequent interconnected chambers with different temperature and pressure conditions.
[0026] A certain measured amount of the dimer is placed into the vaporization chamber, the apparatus is evacuated and the educt is subjected to sublimation at 160° C. and a pressure of 1 mbar. The vapor generated in this way reaches the pyrolysis oven in which the dimer is split, at 690° C., into reactive monomers.
[0027] The monomer molecules condense in the third chamber at room temperature uniformly on all surfaces and polymerize rapidly to a transparent pore-free film.
[0028] In contrast to the industrial procedure wherein generally parylene layers with a thickness of 3 to 15 μm are deposited, the coating process is optimized in this case to the substantially smaller layer thicknesses of 2-200 nm.
[0029] One of the reasons for the use of parylene films in OFW sensor systems resides in the adaptation of the surface energy of the sensor to that of the sorption polymers. The deposited film should, as intermediate layer, ideally have a good adhesion to the substrate as well as a low surface energy in order to improve the wetting properties of viscous polymers.
[0030] For the examination of the wetting behavior of sorption polymers of sensors, which are provided with a thin parylene layer in comparison with uncoated sensors, the following experiments were performed.
[0031] To this end a drop (1.5 μl) of the same polymer solution was placed and dried on the surface of each of several uncoated and parylene-coated sensors. For a comparison of the phase curve changes caused by the coating, the components were characterized before and after the coating by means of a network analyzer.
[0032] [0032]FIG. 1 shows a microscope photography of two OFW sensors drip-coated by the sorption polymer 1 . The left picture shows the good wetting properties of the parylene-coated sensors, the picture at the right indicates the inadequate wetting properties of the untreated sensor.
[0033] For the sensors pretreated with parylene, the wetting of the sensor surface with the sorption polymer is found to be excellent. In comparison, the wetting behavior of the untreated sensor is substantially worse. At the right end of the picture of FIG. 1, it can clearly be seen that the polymer deposited collects at the edges of the active structure of the OFW sensor and that the intermediate surface area is not wetted.
[0034] [0034]FIG. 2 shows the changes of the phase curve by drip-coating with the sorption polymer 1 . The left diagram shows the phase curves of the sensor with the parylene intermediate layer, the right diagram shows those of the sensor without such intermediate layer. With elimination of the cross-links occurring at the sensor surface not coated with parylene by the sorption polymer, the sorption polymer collects preferably near the active interdigital structures and, consequently, at the location of the largest mass sensitivity of the sensor. In this way, however, a greater layer thickness than actually present is simulated which explains the greater shifting of the phase curve to lower frequencies (see FIG. 2, right picture).
[0035] The comparison of the two diagrams of FIG. 2 clearly shows the better phase behavior of the OFW sensor pretreated with parylene. The phase reserve remaining after the drip-coating (=difference between phase minimum and phase operating point of the oscillator electronics) is substantially larger. The small frequency displacement caused by the coating with the same amount of polymer deposited can be explained by its more uniform distribution on the sensor surface. The comparison of the microscope photograph of the two drip-coated sensors in FIG. 1 explains the difference between the sensor properties found in FIG. 2.
[0036] [0036]FIG. 3 shows the change of the phase curve occurring by drip-coating with the sorption polymer 2 . The left diagram shows the phase curves of the sensor with the intermediate parylene layer, the right diagram shows the phase curve of the sensor without intermediate parylene layer.
[0037] In comparison with the phase curves of the sensors according to FIG. 2, the sensor obtained by drip-coating of the untreated sensor with this sorption polymer is not usable. In contrast, after the drip-coating of the parylene-treated sensor with this polymer, there remains a substantial phase reserve. The examination of the sensors by a microscope shows also in this case, that the pretreated sensor has a uniform layer thickness but the untreated sensor shows a destruction of the cross-links in the area between the two active interdigital structures which explains the phase behavior of this sensor.
[0038] The sorption polymer 1 is butylacrylate-ethyl-acrylate copolymer and the sorption polymer 2 is polyurethane, which is linearly cross-linked.
[0039] Particularly advantageous example for the thickness of the two layers:
[0040] Parylene either as thin as possible (adhesion provider about 20-50 nm) or as thick as bearable (corrosion-protection, up to 200 nm).
[0041] Particularly suitable OFW building component:
[0042] The coating was tested among others with: 380 MHz shear wave building component of lithium-tantalate and 433.92 MHz Rayleigh-wave building components (both of quartz). The protection effect and increased wetting by the parylene is universal; it cannot be limited to a particular component. The difference resides only in the maximally applicable layer thickness of the parylene for the different building components since this results in different insertion attenuations.
[0043] The results which can be achieved by the use of the parylene as a thin intermediate layer can be summarized as follows:
[0044] The intermediate layer acts as an adhesion provider between the inorganic substance surface and the sorption polymer by lowering the surface energy of the sensor. In this way, on one hand, the wetting properties and, on the other hand, the aging behavior of the sensors are substantially improved. Any desired sorption polymers may now be used without the need to fear destruction of the cross-links.
[0045] With the application of the parylene film, a diffusion barrier for corrosive materials is formed which protects the sensor from aggressive ambient influences. At the same time, the effect of a signal reversal upon the application of samples with analytes of different polarity is prevented, since the respective analyte can no longer reach the surface of the sensor substrate.
[0046] Because the wetting properties are improved by the parylene intermediate layer, the pretreated sensors may be coated by means of the relatively simple drip-coating process.
[0047] The good wetting of the parylene-coated sensors with sorption polymers facilitates the coating of the sensors up to the critical phase reserve and consequently results in the achievement of a maximal sensitivity of the respective sensors. | In a method for producing surface wave sensors on the basis of a surface wave building component a polymer parylene film with a thickness of 20 to 200 nm is applied to a hydrophilic sensor surface of the surface wave building component by deposition from the gas phase, whereby the hydrophilic sensor surface becomes hydrophobic, the surface is then subjected to plasma activation to render it hydrophilic and a hydrophilic sorption polymer layer is then applied to the parylene film so as to provide a surface wave sensor with a homogenous sorption polymer layer. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is related to U.S. Provisional Patent Application No. 62,191,313, which was filed on Jul. 10, 2015, and entitled “CEMENT BLOCKS HAVING NOTCHES FOR INTERCONNECTIVITY” and U.S. Provisional Patent Application No. 62/193,062, which was filed on Jul. 15, 2015, and entitled “RETAINING WALL SYSTEM USING INTERBLOCKING CONCRETE MASONRY UNITS.” U.S. Provisional Patent Application Nos. 62,191,313 and 62/193,062 are hereby incorporated by reference into the present application as if fully set forth herein. The present application hereby claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Nos. 62,191,313 and 62/193,062.
TECHNICAL FIELD
[0002] This disclosure is generally directed to cement block designs. More specifically, this disclosure is directed to a retaining wall system using interlocking concrete masonry units.
BACKGROUND
[0003] Concrete masonry units (CMU) are also called concrete bricks, concrete blocks, cement blocks, besser blocks, breeze blocks, and cinder blocks. Here, the term “cement block” will be employed.
[0004] Cement blocks are ubiquitous and produced all over the world. Furthermore, they are extremely inexpensive. Commonly, they are used to construct buildings; however, they can also be used to construct retaining walls.
SUMMARY OF THE DISCLOSURE
[0005] The present disclosure is directed to a new and improved family of cement block designs that have notches included therein to allow interconnectivity. In particular embodiments, the notched interconnectivity strengthens the combined block structure as compared to a structure of combined conventional blocks. Alternative embodiments replace notches with clips that create interconnectivity.
[0006] Before undertaking the DETAILED DESCRIPTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] For a more complete understanding of this disclosure and its features, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:
[0008] FIG. 1 is a collapsed retaining wall constructed from cement blocks joined by mortar;
[0009] FIG. 2 is a base layer of cement blocks;
[0010] FIG. 3 is a second layer of cement blocks added to base layer of FIG. 2 ;
[0011] FIG. 4 show a second layer of cement blocks with notches to create interlocking blocks, according to an embodiment of the disclosure;
[0012] FIG. 5 is a bottom view of cement block of FIG. 4 , showing six notches;
[0013] FIG. 6 is a side view of stacked cement blocks described in FIG. 4 where blocks are oriented in the same direction;
[0014] FIG. 7 is a side view of stacked cement blocks described in FIG. 4 where blocks are oriented in the alternating directions;
[0015] FIG. 8 is a second layer of cement blocks with double set of notches, according to another embodiment of the disclosure.
[0016] FIG. 9 is a side view of stacked cement blocks described in FIG. 8 ; and
[0017] FIG. 10 shows conventional cement blocks without notches joined with interlocking right-angle clips; and
[0018] FIG. 11 shows conventional cement blocks without notches joined with interlocking parallel-angle clips.
DETAILED DESCRIPTION
[0019] The FIGURES described below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure invention may be implemented in any type of suitably arranged device or system. Additionally, the drawings are not necessarily drawn to scale.
[0020] Concrete masonry units (CMU) are also called concrete bricks, concrete blocks, cement blocks, besser blocks, breeze blocks, and cinder blocks. Here, the term “cement block” will be employed.
[0021] Cement blocks are ubiquitous and produced all over the world. Furthermore, they are extremely inexpensive. Commonly, they are used to construct buildings; however, they can also be used to construct retaining walls.
[0022] FIG. 1 shows a collapsing retaining wall constructed from cement blocks joined by mortar. When used in the conventional manner joined with mortar such as shown in FIG. 1 , cement blocks are not particularly strong. Strength can be significantly increased by laying the cement blocks as shown in FIG. 2 , which has double the depth compared to the conventional approach shown in FIG. 1 .
[0023] FIG. 3 shows a second layer of cement blocks added in an offset and overlapping manner to the base layer of FIG. 2 . If such a wall were joined with cement, it would not be strong because there is little contact area between the layers.
[0024] With the identified concerns of configurations shown in FIGS. 1 through 3 , certain embodiments of the disclosure provide a better approach for interconnecting cement block. In particular, certain embodiments allow an interconnectivity through placement of notches in the cement blocks.
[0025] FIG. 4 shows an example notch in a cement blocks, according to an embodiment of the disclosure. In FIG. 4 , the block on the second layer has six notches (three of which are seen), which interlock the blocks creating a much stronger wall than that shown in FIG. 3 . Among other things, the surface area contact is increased. Also the interconnectivity restricts lateral movement—not only of one block with respect to another, but also (in this figure) three blocks with respect to each other.
[0026] FIG. 5 shows a bottom view of the second-layer block of FIG. 4 in which the six notches are readily seen. Although this particular location is provided, one of ordinary skill in the art will recognize that the notches can be placed in other locations.
[0027] FIG. 6 shows a sloped wall constructed from the cements blocks described in FIG. 4 . Each block is oriented in the same direction.
[0028] FIG. 7 shows the cement blocks stacked so as to create a vertical retaining wall. Each block is oriented in an alternating direction.
[0029] FIG. 8 shows a second layer of cement blocks with a double set of notches, one set on the bottom and the other set on top. This system allows every other layer to be constructed of conventional un-notched cement blocks. The intermediate layers are notched.
[0030] FIG. 9 shows a vertical wall constructed from the cements blocks described in FIG. 8 .
[0031] FIG. 10 shows an alternative approach that employs clips to join the blocks together. Each clip employs channels in the x and y axes onto which webs of the adjoining cement blocks can be aligned. In one axis, the clip is the width of two webs. In the other axis, it is the width of one web. The clips can be made from any suitable material such as metal, plastic, cement, or ceramic. For additional strength, the latter three materials can be reinforced with fibers. FIG. 10 shows three clips; however, fewer or more can be employed. For additional strength, the clips can be bonded to the cement blocks using suitable mortar or glue, such as epoxy.
[0032] FIG. 11 shows an alternative approach that employs parallel-angle clips to join the blocks together. Each clip employs channels in only the x axis onto which webs of the adjoining cement blocks can be aligned. In each axis, the clip is the width of one web. The clips can be made from any suitable material such as metal, plastic, cement, or ceramic. For additional strength, the latter three materials can be reinforced with fibers. FIG. 11 shows four clips; however, fewer or more can be employed. For additional strength, the clips can be bonded to the cement blocks using mortar or suitable glue, such as epoxy.
[0033] To create yet additional strength, the void space in the concrete blocks can be filled with rebar and cement.
[0034] The sloped wall shown in FIG. 6 can be filled with soil allowing plants (e.g., vines) to grow on the wall, thus creating a “living wall.”
[0035] In particular embodiments, the wall may be constructed from conventional concrete blocks; however, the blocks can be decorative with attractive textures or colors on the face.
[0036] In particular embodiments, the notched designs can be created by taking existing concrete block molds and retrofitting them with the notch to not “fill” an otherwise fillable area. Thus, using such a manufacturing technique, an owner of molds need not purchase additional molds. They need only insert the additional retrofit pieces.
[0037] This retrofit approach to manufacturing interlocking pieces by removing material from an otherwise conventional block has advantages over alternative strategies that would add to (as opposed to remove from) an otherwise conventional block. The add-to alternative strategy is much more expensive and difficult to implement because additional hardware and manufacturing steps are required.
[0038] Although a retrofit design has been described with reference to particular embodiments to avail from existing molds, other embodiments may be specifically design a mold with a notched design in mind. Moreover, some mold designs may have dynamically changeable pieces to slightly modify where notches are placed.
[0039] Although particular location of notches have been describe herein, after review of this disclosure, one of ordinary skill in the art will recognize that notches may be placed in other locations. As a non-limiting example, in FIG. 4 , the interconnectivity may be enabled by notches on both layers as opposed to one layer shown.
[0040] Additionally, although particular types of cement blocks have been shown, other types of cement blocks may be utilized with notches therein. Such other types of cements blocks may include blocks with one hole, three or more holes, and holes with different sizes. Such cement blocks may be standard ones or non-standard ones. Retrofit and dynamic retrofit may apply to any of preceding.
[0041] Additionally, although “cement” is described as a particular material for blocks, in some embodiments, other materials may be utilized.
[0042] While this disclosure has described certain embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of example embodiments does not define or constrain this disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of this disclosure, as defined by the following claims. | The present disclosure is directed to a new and improved family of cement block designs that have notches included therein to allow interconnectivity. In particular embodiments, the notched interconnectivity strengthens the combined block structure as compared to a structure of combined conventional blocks. Alternative embodiments replace notches with clips that create interconnectivity. | 4 |
GOVERNMENTAL INTEREST
The invention described herein may be manufactured, used and licensed by or for the Government for Governmental purposes without the payment to me of any royalties thereon.
BACKGROUND OF THE INVENTION
The present invention relates to projectiles and in particular to a projectile having a cavity containing a fluid.
To obtain a satisfactory range from a projectile it is necessary to stabilize its orientation to prevent excessive yaw or pitch. While judicious design of the center of gravity or the inclusion of fins may provide an aerodynamic moment which assures stability, a large class of projectiles rely on spin stabilization. Through the use of rifling, a launched projectile is spun about its longitudinal axis so that it exhibits the wellknown gyroscopic effect. To ensure that a projectile is gyroscopically stabilized its spin rate must exceed a minimum which is determined by factors such as its mass distribution.
A specific cannon or gun having standard rifling does not have the ability to adjust the spin rate or the stability of various projectiles. In order to vary the spin rate a known barrel employed two interlaced riflings having differing twist rates. A projectile having engravings matching the appropriate one of the riflings is manually inserted therein. This approach however, does not allow continuous adjustment of spin rate and does not affect projectile stabilizing characteristics such as its mass distribution. In a known projectile, a slipping obturator is used to reduce the spin rate. This apparatus is exposed to high stress and does not provide for adjustment of stabilizing factors such as the mass distribution of the projectile. In a known launcher, its barrel is spun at a rate appropriate for the projectile being fired. While the spin rate can be adjusted in this apparatus, the highest rate attainable is limited and wear is a problem.
The present invention provides a projectile whose flight stability is controlled by a fluid disposed in a cavity of the projectile. The cavity is arranged to allow shifting of the fluid. The resulting mass redistribution can affect flight stability by altering the moment of inertia or the center of gravity as the projectile is trajected. Such mass redistribution can be utilized to increase or decrease the flight stability, in various embodiments. Also, prior to launch the flight stability can be set by the simple expedient of selecting a specific volume or density of fluid. The setting of stability in this fashion may be performed in the factory or in the field. This latter feature is also useful where a standard shell is to be fitted with any one of variously shaped explosives of differing densities.
In addition, for some embodiments the fluid employed may be a liquid explosive so that dead weight is avoided.
Moreover this shifting of fluid may be arranged to facilitate high angular acceleration during launch, thereby ensuring rapid attainment of the rated spin rate. In some embodiments the fluid shift may occur over a predetermined interval so that the projectile stability varies throughout its trajectory. This feature may be important where it is desired to destabilize the projectile and cause it to fall when it reaches a target.
SUMMARY OF THE INVENTION
In accordance with the illustrative embodiments demonstrating features and advantages of the present invention, there is provided a projectile having variable stability. The projectile is arranged to be spin stabilized. The projectile includes a casing having a cavity. Fluid of a given mass is contained within the cavity. The cavity is shaped to provide a balanced flow of the fluid with respect to the axis of spin as the projectile is trajected. This balanced flow alters the flight stability of the projectile.
BRIEF DESCRIPTION OF THE DRAWINGS
The above brief description as well as further objects, features and advantages of the present invention will be more fully appreciated by reference to the following detailed description of presently preferred but nonetheless illustrative embodiments in accordance with the present invention when taken in conjunction with the accompanying drawings wherein:
FIG. 1 is a cross-sectional view of a projectile of the instant invention;
FIGS. 2A, 2B and 2C are partial views of the fluid cavity of FIG. 1 showing shifting of the fluid therein;
FIG. 3 is a cross-sectional view, broken on the right, of a second embodiment of a projectile of the instant invention;
FIG. 4 is a view similar to that of FIG. 3 but in which fluid shift has occurred;
FIG. 5 is a cross-sectional view, broken on the right, of a third embodiment of a projectile of the instant invention; and;
FIG. 6 is a detail view of the normally closed valve means of FIG. 5, showing that valve open.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now specifically to the drawings, in FIG. 1 a projectile is shown therein as a casing 10 having a cylindrical cavity 12. While the outline of casing 10 is essentially that of a cylinder with a tapered forward end 14, it is apparent that other shapes including blunt nosed shapes may be employed. Also, cavity 12 may be sized, shaped and located differently than shown and may in some embodiments have a frustro-conical or bell shape. Moreover, as described hereinafter cavity 10 may be multi-chambered. The considerations underlying such cavity design are discussed subsequently. These cavities are shaped, however, to provide a balanced flow about the longitudinal axis of the projectile. While axially symmetric shapes will normally provide balanced flows, other shapes such as a non-symmetrical manifold can be shaped to provide such balance.
A fluid is shown herein as liquid explosive 16. In this embodiment it fills about 40% of cavity 12 although this percentage can be significantly altered to suit the geometry of cavity 12 and casing 10 and to provide the desired gyroscopic stability. In other embodiments the ullage of cavity 12 may be taken up by an immiscible liquid having a density differing from that of fluid 16. Eliminating ullage in this fashion cannot only influence gyroscopic stability but may be useful for eliminating splashing or for delaying fluid shift. For reasons given hereinafter cavity 12 may also advantageously employ inwardly projecting paddles for affecting fluid translation. Cavity 12 is sealed with bolt 18.
The aft end of the projectile is capped by base plate 20 which has a threaded inner end and an outer end having a diameter matching that of casing 10. A pair of wrench holes 22 are provided which accept a spanner wrench. Aft cavity 24 and forward cavity 26 are to be filled with appropriate explosives. For example, a shaped charge with a conical metal liner (not shown) may be suitably installed in forward cavity 26, although other warheads may be employed. The forward cavity is sealed and capped by a well-known point detonating fuse 28, which initiates the explosive train upon impact. Fitted into a circumferential groove in casing 10 is a conventional rotating band-obturator 30.
At set back, the projectile of FIG. 1 is violently accelerated, causing fluid 16 to flow rearward and form the cylinder illustrated herein. If the projectile is launched through a barrel incorporating rifling, the projectile will also be angularly accelerated to produce spin. This spinning motion is imparted to fluid 16 which is vortically impelled by the walls of cavity 12. As previously mentioned, inwardly projecting paddles may be affixed to the walls of cavity 12 to reduce, if desired, any lag between the spin rates of casing 10 and fluid 16.
As the spinning projectile accelerates toward the muzzle (not shown) the surface of fluid 16 has the concave parabolic shape illustrated in FIG. 2A. The shape taken is determined by the reactive force on the liquid caused by its forward acceleration and the centrifugal force caused by its revolution. As is well known, the former force is proportional to the product of the fluid mass and its acceleration while the latter force is proportional to the product of the fluid mass, its radial position and the square of its angular velocity. The depth of the concave surface of fluid 16 will be a direct function of this centrifugal force and an inverse function of this reactive force due to forward acceleration. Accordingly a higher angular velocity or lower forward acceleration can produce the deeper vortex shown in FIG. 2B.
After leaving the muzzle, the forward acceleration of the projectile will be zero while its spin rate (angular velocity) will be about maximum. Since this condition corresponds to maximum centrifugal and zero rearward force, fluid 16 is propelled radially outward to form the cylindrical annulus shown in FIG. 2C.
To appreciate the effect of the transformation of fluid 16 from the solid cylindrical shape of FIG. 1 to the annular shape of FIG. 2C, the gyroscopic qualities of a projectile will be briefly considered. The well-known gyroscopic stability factor is proportional to:
p.sup.2 (Ix).sup.2 /Iy (Cm)
where Cm is the well-understood static moment coefficient about the center of gravity of the projectile, p is the spin rate of the projectile and Ix is the moment of inertia about this axis of spin. The moment of inertia about an axis orthogonal to that of moment Ix, through the projectile's center of gravity, is referred to as moment Iy. Increase in this gyroscopic stability factor corresponds to enhanced flight stability. It will be readily observed that the numerator of the foregoing expression is essentially the angular momentum associated with projectile spin, squared. Accordingly, conservation of momentum requires that any fluid transformations occurring in free flight will not affect this numerator. The magnitude of this numerator will be established by the spin p attained and the moment of inertia Ix existing at the muzzle. Spin p will be primarily determined by the rifling. The moment of inertia Ix will be determined by the specific shape of fluid 16, as exemplified in FIGS. 2A and 2B.
Once in flight, the denominator of the foregoing expression may change, although the numerator is invariant. While shifting of fluid 16 (FIGS. 1 and 2C) can displace the center of gravity of the projectile, thereby affecting the static moment coefficient Cm, a predominating effect for this embodiment is variation in the transverse moment of inertia Iy. In this embodiment the transverse moment Iy decreases to cause an increase in gyroscopic stability. The respective transverse moments of inertia of the fluid 16 in the configurations of FIGS. 1 and 2C may be readily obtained using well known formulas. These moments of inertia are taken with respect to the center of gravity of the projectile. For the embodiment of FIGS. 1 and 2C, this center is, for practical purposes, located in the center of cavity 12. While the shifting of fluid 16 may shift the center of gravity, this small effect will not be considered in the following analysis.
To calculate such variation in the moment of inertia, the moment of inertia of an annular cylinder, having an outside diameter D2 and inside diameter D1, about a central transverse diameter is obtained from the well known formula (unit mass assumed):
D1.sup.2 /16+D2.sup.2 /16+(Lc+d).sup.2 /12
where the bracketed quantity equals the length of the annular cylinder but expressed as the sum of the length Lc of the solid fluid cylinder of FIG. 1 and the length d of its resulting empty cylinder. The moment of inertia about a central diameter in cavity 12 for fluid 16 in FIG. 1 may be obtained using the well known parallel axis theorem. It is apparent that the center of gravity of fluid 16 for FIG. 1 is offset d/2 from the axis of rotation so that its moment of inertia is (unit mass assumed):
D2.sup.2 /16+(Lc).sup.2 /12+d.sup.2 /4
The net decrease in moment of inertia is obtained by subtracting the former expression from the latter and substituting the term e for the ratio of d/Lc. The resulting expression is: ##EQU1## It is immediately observed that for the moment of inertia to decrease, the above expression must be positive. As a result, e must exceed unity which requires the cavity 12 to be less than 50% full. With this in mind, the size, fullness and slenderness of cavity 12 may be chosen to provide the desired decrease in moment of inertia. Moreover, the foregoing expression assumes unit mass and therefore it can be generalized by multiplying by the mass of fluid 16.
Accordingly it is apparent that by the simple expedient of altering the volume or density of fluid 16 gyroscopic stability during free flight can be readily increased or decreased. In this fashion the extent of fluid shifting occurring after setback, can be used to establish the desired gyroscopic stability.
Referring to FIG. 3 an alternate embodiment is illustrated in which a projectile is shown having a pair of chambers 32 and 34. While this pair is shown as an inner cylindrical chamber 32 coaxially disposed within an outer annular chamber 34 having opposing cylindrical surfaces, other arrangements are possible. For example, either one of the pair of chambers 32 or 34 may be a multi-chambered manifold which is longitudinally displaced from the other. The specific arrangement is chosen to provide the desired change in gyroscopic stability.
The projectile casing is formed of flight body 36, which is broken on the right for illustrative purposes, and pedestal 38. Body 36 and pedestal 38 are attached together by threads 40, threading being facilitated by spanner wrench holes 42 in pedestal 38. Body 36 and pedestal 38 are sealed by toroidal gasket 39 (O ring) which is disposed in a rectangular circumferential groove in pedestal 38. Both body 36 and pedestal 38 are axially symmetric and may be considered solids of revolution, with the exception of holes 42 and passageways 44 and 46 which passageways are described hereinafter. Fitted into a circumferential groove in body 36 is conventional rotating band obturator 47.
Fitted into inner chamber 32 is inner piston 48 which is shown as a relatively short cylinder with a circumferential groove containing a toroidal gasket 50. Fitted into outer chamber 34 is outer annular piston 52 having an inner and outer circumferential groove containing toroidal gaskets 54 and 56, respectively. Pistons 52 and 48 may, of course, be shaped differently in other embodiments and may employ cross-sections which are circular, hollow, pitched etc.
Communication between the forward ends of chambers 32 and 34 is provided by passageway 58 which allows fluid 60 to flow radially between them. Fluid 60 is trapped between pistons 48 and 52 whose respective gaskets 50, 54 and 56 prevent fluid 60 from bypassing these pistons. So configured, a forward force on outer piston 52 applies hydraulic pressure on inner piston 48, tending to drive it backwards. For well understood reasons, forward motion of piston 52 produces displacement of piston 48 in inverse proportion to the surface area it presents to fluid 60.
A drive means is shown herein having a source of pressurized gas disposed in an elongated chamber. In this embodiment the source is gas capsule 62 disposed in an axial circular bore in pedestal 38. It is apparent that other drive means are possible and, in fact, an alternative is illustrated hereinafter. Means for urging capsule 62 forward is provided by coil spring 64 which bears against anvil 66. Anvil 66 has a generally cylindrical shape but with a small pointed projection on its forward surface and a wrench hole in its rear surface. Anvil 66 is threaded into pedestal 38 and sealed thereto by toroidal gasket (O ring) 68. Capsule 62, containing pressurized CO 2 or other gaseous propellants, has an aft frangible seal aligned with the pointed projection of anvil 66. As an alternative to a pressurized capsule, a source of pressurized gas may be provided by a detonatable cartridge (appearing similar to capsule 62) which is detonated by collision with a trigger means such as anvil 66.
Passageway 46 provides communication between the bore containing capsule 62 and the aft of outer chamber 34. Passageway 44 is sealed with plug 70 which is pressure ejectable. Dislodging of plug 70 vents the aft of inner chamber 32.
To facilitate an understanding of the embodiment of FIG. 3 its operation will be briefly described in conjunction with FIG. 4. At set-back the projectile is instantaneously accelerated causing capsule 62 to recoil and impale its frangible seal against the pointed projection of anvil 66. When launched into free flight, forward acceleration ceases and capsule 62 is urged to the position shown in FIG. 3, releasing its pressurized CO 2 . This pressurized gas communicates with the aft of outer chamber 34 by means of passageway 46. It will be observed that capsule 62 is loosely fitted into its axial bore to allow gas to bypass it. The resulting pressure on the aft face of outer piston 52 causes it to slide forward and piston 48 to slide aftward, for the reasons previously given. The aftward translation of piston 48 creates a back-pressure in passageway 44 which dislodges plug 70 and vents the aft of chamber 32 (FIGS. 3 and 4). Under such circumstances, pistons 48 and 52 and fluid 60 are free to shift to the positions shown in FIG. 4. This motion ceases upon either piston 52 or 48 abutting the end of its respective chamber--provided capsule 62 has sufficient drive capacity.
It is apparent that the fluid transformation illustrated by FIGS. 3 and 4 effectively condenses a hollow cylinder of uniform wall thickness into a solid fluid cylinder. It is also apparent that the initial and final centers of gravity of fluid 60 are approximately coincident. This being the case, the moment of inertia of fluid 16 with respect to anyone of its diameters is less for the final fluid configuration of FIG. 4. This decrease may be perceived intuitively as a result of the condensed solid cylinder having more fluid elements closer to the transverse axis. By assuming the interspace between chambers 32 and 34 is negligibly small, the decrease in this moment of inertia may be approximated as 1/16 of the product of the mass of fluid 60 and the square of the diameter of chamber 32. A more detailed analysis, using well known mathematical techniques, could evaluate the influence of any shift in the center of gravity of fluid 60, to obtain a more accurate estimate of the moment of inertia variation.
The fact that the outer chamber 34 encompasses chamber 32 together with the fact that the center of gravity of fluid 60 does not appreciably shift, is advantageous. The length to thickness ratios of chambers 32 and 34 may be varied significantly without eliminating the decrease in moment of inertia caused by the foregoing fluid transformation. In comparison, the fluid transformation from FIG. 1 to FIG. 2C decreases the moment of inertia about a transverse diameter through the projectile's center of gravity by moving into coincidence therewith the center of gravity of fluid 16. This effect in FIGS. 1 and 2C, however, is offset by the fact that the moment of inertia of fluid 16 about its own center of gravity is less for the initial position of FIG. 1. Thus for the embodiment of FIG. 1, some cavity shapes provide insufficient shift in fluid center of gravity so that this effect is overcome by the higher inherent moment of inertia for the fluid shape of FIG. 2C.
In contrast, the arrangement of FIGS. 3 and 4, by eliminating reliance on the shift in center of gravity, avoids countervailing phenomena which can reduce the net change in moment of inertia about a diametric axis.
Referring to FIG. 5 an inner chamber 72 is encompassed by an outer annular chamber 74 which intercommunicate by means of radial passageway 76. Fitted within inner chamber 72 is a relatively short cylindrical piston 78 having a circumferential groove containing toroidal gasket 80. An annular piston 82 has opposing circumferential grooves on its inside and outside surface which contain toroidal gaskets 84 and 86, respectively. The foregoing describes a hydraulic system which operates with fluid 88 and which cooperates in the same manner as previously described in connection with FIG. 3. In distinction to FIG. 3, the pistons in the apparatus of FIG. 5 are to be driven in directions opposite to that of FIG. 3. To this end flight body 90 has a circular aperture 91 which vents the aft end of chamber 74.
Threaded into body 90 is pedestal 92 which, except for certain passageways hereinafter described, is essentially a solid of rotation. Threaded into the aft end of pedestal 92 is cup shaped plug 94, threading being facilitated by a pair of spanner wrench holes 96.
A normally closed valve means is shown herein as a tapered valve member 98 having a cupped shape. Member 98 is urged forward by a yieldable means, shown herein as coil spring 100. It is apparent that other valve devices including various check valves may be employed herein as alternatives. In the position shown, valve member 98 seals inlet port 102 which communicates with cylindrical plenum 104. Plenum 104 communicates with the aft of inner chamber 72 by means of circular passageways 106 and 108. Valve member 98 is exposed to ambient pressure by a pair of skewed passageways 110 and 112 which are vented to ambient. It is to be understood that during launch, the ambient will be a high pressure gun gas.
At set back two forces tend to retract valve member 98: recoil forces and a high pressure gun gas bearing upon its tapered surface. In response, valve member 98 retracts as shown in FIG. 6. Under this condition port 102 is opened and a high pressure gun gas passes therethrough, pressurizing plenum 104. As the projectile reaches the muzzle, acceleration and ambient pressure rapidly decline, so that spring 100 overcomes these effects and returns member 98 to the position shown in FIG. 5. Upon closing, valve member 98 seals port 102, entrapping high pressure gas in plenum 104.
The high pressure of plenum 104 is communicated to the aft face of piston 78 driving it forward. In a manner analogous to the hydraulically coupled pistons of FIG. 3, the pistons 78 and 82 move in opposite directions, in inverse proportion to the surface area each presents to fluid 88. In contrast to the arrangement of FIG. 3, this arrangement shifts fluid 88 to outer chamber 74 which, for reasons previously given, causes a decrease in gyroscopic stability. Such a feature may be useful for practice projectiles whose range must be limited to avoid unforeseeable damage. Alternatively, the size of passageway 76 may be constricted or the viscosity of fluid 88 may be so great that the shift of fluid 88 occurs over a predetermined time interval. This feature may be used to destabilize the projectile at a given range at which a target is located.
From the foregoing it is apparent that various shaped cavities containing shiftable fluid may be designed in accordance with the teachings of the present invention. Moreover, various components in the several embodiments may be interchanged. Also the size, location, density and viscosity of the components herein disclosed may be altered to provide a desired stability, weight, center of gravity etc. Obviously many other modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | A spin stabilized projectile is arranged to have variable flight stability.he projectile has a casing with a cavity that contains a given mass of fluid. The cavity is shaped to provide a balanced flow of fluid with respect to the axis of spin as the projectile is trajected. This balanced flow alters the flight stability of the projectile. | 5 |
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