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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is in the field of deferred action, water activated electric cells, methods of making them, and survival lamps embodying them.
2. Description of the Prior Art
Deferred action or reserve type electric cells for use as emergency or survival equipment utilizing a magnesium anode and a silver halide cathode, and adapted for activation by the addition of an aqueous fluid, have been known in the art for some time. Magnesium is a preferred anode material for such deferred action cells because it is high in the electromotive series, has good structural strength yet is light in weight, is easy to form, and is readily available. However, magnesium is very active chemically, and therefore readily corrodes from handling, from exposure to the atmosphere and particularly the damp, salty atmosphere of a marine environment where survival equipment is commonly used, and from proximity to some chemicals and in particular chemical salts employed in an electrolyte solution for the cell.
Primarily because of this problem of corrosion of the magnesium anode, prior art deferred action electric cells adapted for emergency or survival use have not included any electrolyte material therein, either in dried form or as a liquid solution, and accordingly in order to activate such cells it was necessary to add a whole or complete electrolyte solution thereto. This generally restricted such deferred action cells to usage in connection with ocean survival equipment, wherein the salt water provided the necessary whole electrolyte required for activation. Such usage of sea water as the electrolyte resulted in less than optimum activation because sea water is not a saturated salt solution. Also, such salt water activated cells were generally complicated physically by the need for controlled entrance passages, fluid flow separators, chambers to accommodate an accumulation of flake-off from the magnesium anode, and the like.
Example of prior patents disclosing such deferred action electric cells embodying magnesium anodes and silver halide cathodes which require the addition of a whole or complete electrolyte, and which are accordingly generally restricted to use in a salt water environment, are the following U.S. Pat. Nos.:
Warner et al: 2,663,749
Lockwood: 2,896,067
Armitage: 3,326,724
While both the Warner U.S. Pat. No. 2,663,749 and the Armitage U.S. Pat. No. 3,326,724 suggest that fresh water could be used as the electrolyte, and in this connection the Armitage patent suggests the electrolyte can be formed of water along with the reaction product salts from the electrolytic action, nevertheless, fresh water is an exceedingly poor electrolyte, and if it is the only electrolyte added for activating the cell, activation will be much too slow, and the resulting current capability of the cell much too low, for reliable and satisfactory operation of the cell in emergency or survival equipment.
Because the corrosiveness of the magnesium anode material has in the past tended to make deferred action electric cells generally unreliable after an extended shelf life, and therefore generally inadequate for use in emergency or survival equipment, there have been prior art attempts to provide a satisfactory corrosion-resistant coating on the magnesium. However, heretofore the procedures and chemical actions required to produce such corrosion-resistant coatings on the magnesium have been so complex, time-consuming and expensive that they have not been generally satisfactory. The Warner et al U.S. Pat. No. 2,663,749 referred to above describes one such magnesium coating procedure; and the Gruber et al U.S. Pat. No. 3,303,054 describes another complex magnesium coating procedure which is employed in the manufacture of "dry cells" which are not of the delayed action type and therefore have a limited shelf life and reliability not suitable for survival equipment.
SUMMARY OF THE INVENTION
In view of these and other problems in the art, it is an object of the present invention to provide a novel deferred action electric cell of the type embodying a magnesium anode and a silver halide cathode, which includes dried electrolyte material supported intermediate the electrodes, whereby any aqueous fluid, which can be fresh or even distilled water, added to the cell will immediately develop the full electrical output potential of the cell.
Another object of the invention is to provide a novel method of coating the magnesium anode of a water-activated deferred action electric cell, wherein a detergent bath produces a coating on the anode that prevents corrosive deterioration of the magnesium from the atmosphere, even in marine areas, from handling, and more particuarly from close proximity of the anode to a dried, water soluble electrolyte material, thereby enabling provision of a complete deferred action electric cell of the character described that contains electrolyte and requires only the addition of water for reliable, immediate and full voltage activation after an extended shelf life.
Another object of the invention is to provide a deferred action electric cell of the character described having a novel mechanical construction embodying the coated magnesium anode as a tubular outer body or shell, the silver halide cathode, preferably silver chloride, in the form of a rolled sheet thereof disposed concentrically within the anode tube, and a rolled sheet of resilient, porous, absorbent insulation material saturated with dried electrolyte disposed in resilient biasing engagement between the anode and cathode for secure relative positioning thereof and intimate dielectric contact therebetween; the porosity of this dried electrolyte-supporting insulation material preferably including perforations extending through the sheet of material for improved ion exchange characteristics and as receptacles for magnesium hydroxide flakes coming off of the anode.
A further object of the invention is to provide a deferred action electric cell of the character described which includes a novel means for releasably supporting a light bulb in one end of the cell, wherein the cell includes a tubular outer magnesium anode shell having an outwardly flaring tapered inner surface in the bulb-receiving end; the bulb having a tapered, externally threaded base portion forming one electrical terminal thereof; and a deformable lock thread element loosely threadedly engaged on the base of the bulb proximate its free end; whereby the base of the bulb with the lock thread element thereon may be pushed down into the tapered bore of the magnesium body and the bulb screwed further into the lock thread element to provide tight wedging engagement with good electrical contact between the base of the bulb, lock thread element and anode body of the cell.
A further object of the invention is to provide a survival or emergency lamp embodying a deferred action electric cell of the character described, wherein the tubular magnesium anode is utilized as the body of the lamp, with a light bulb seated in one end thereof and the other end open for introduction of an aqueous fluid of any character for substantially instantaneous activation thereof after a prolonged shelf life.
A still further object of the invention is to provide another form of survival or emergency lamp embodying a deferred action electrical cell of the character described, which is adapted to be dropped into a body of water as a floating signal light, wherein the deferred action cell is sealed inside of a can-like cylindrical container having a light-transmitting dome at the top with a light bulb that is electrically connected to the cell exposed in such dome, and with the bottom of the container adapted to be torn out along a tear or score line to expose the cell prior to dropping the unit into the water.
A more general object of the invention is to provide a novel deferred action electric cell of the character described which is simple in construction, easy to assemble, attractive in appearance, compact, generally self-contained having dried electrolyte material embodied therein so as to require only the addition of water for activation, and having a prolonged shelf life without substantial deterioration.
Further objects and advantages of the present invention will appear during the course of the following part of the specification, wherein the details of construction, mode of operation and novel method steps of a presently preferred embodiment are described with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating a deferred action electric cell according to the invention, the cell embodying a light bulb so that the unit constitutes a survival or emergency lamp.
FIG. 2 is another perspective view showing the deferred action electric cell of FIG. 1.
FIG. 3 is an enlarged axial section taken on the line 3--3 in FIG. 1, with portions shown in elevation, showing internal details of construction of the cell.
FIG. 4 is a still further enlarged transverse section taken on the line 4--4 in FIG. 3.
FIG. 5 is a transverse section similar to FIG. 4 but taken on the line 5--5 in FIG. 3.
FIG. 6 is a greatly enlarged, fragmentary axial section of the region designated 6 in FIG. 3.
FIG. 7 is a plan view illustrating a presently preferred sheet of resilient, porous, perforated, absorbent insulation material employed in the invention as a support medium for the dried electrolyte material.
FIG. 8 is an exploded perspective view illustrating a light bulb and lock thread element employed in the invention.
FIG. 9 is an elevational view, with portions broken away, and portions shown in vertical section, illustrating a survival or emergency lamp embodying the present invention, which is adapted to be dropped into a body of water as a floating signal light.
FIG. 10 is a horizontal section taken on the line 10--10 in FIG. 9.
FIG. 11 is a horizontal section similar to FIG. 10, but taken on the line 11--11 in FIG. 9.
FIG. 12 is a bottom plan view of the survival or emergency lamp illustrated in FIG. 9.
DETAILED DESCRIPTION
Referring to the drawings, and at first to FIGS. 1 to 8 thereof, a presently preferred form of deferred action electric cell according to the invention is generally designated 10, and includes a cylindrical shell composed of magnesium which serves as both the body and the anode of the cell. The magnesium may be any magnesium alloy conventionally employed in deferred action or other primary electric cells. An example of a suitable magnesium alloy, which is given by way of example only, and not of limitation, is AZ31B magnesium.
While the magnesium shell 12 of the deferred action cell 10 may be of any desired dimensions within the scope of the invention, a size which has been found practical in test cells, for compactness, adequate anode area for good current capacity, and for engagement of a light bulb of conventional dimensions and lock thread element in one end according to the invention, is magnesium tubing of 0.070 inch wall thickness having an ID approximately 1/2 inch, with a length of approximately 21/2 inches. The cell as shown in FIGS. 1 and 2 is slightly larger than the actual size of such test units, while the cell as shown in FIG. 3 is slightly larger than twice the actual size of such test units.
The cylindrical anode shell 12 has a front or terminal end 14, and a rear or water inlet end 16. While a deferred action electric cell 10 according to the invention can be utilized for any purpose, it is particularly useful as a survival or emergency lamp, and in a compact form of such lamp a light bulb generally designated 18 is seated directly in the front or terminal end 14 of the anode shell 12 as best shown in FIGS. 1 and 3. The light bulb 18 includes a generally spherical glass portion 20 that is larger than the ID of the shell 12 at its front end 14 so that the glass portion 20 of the bulb will seat in the front end 14 of the shell but will for the most part project outwardly from the shell to provide good illumination when energized.
The light bulb 18 also includes an outer terminal 22 in the form of a threaded, tapered base having its smallest diameter proximate its free end, the bulb having a center terminal 24 projecting outwardly from the free end of the base 22. The anode shell 12 is provided with a forwardly and outwardly flaring inside surface 26 opening at the front end 14, which is employed in cooperation with the generally complementary tapering of the light bulb base 22 and an intermediate lock thread element 28 for rapid and secure assembly of the light bulb 18 in the front end portion of the anode shell 12. The lock thread element 28 is preferably a single wire loop as best shown in FIG. 8, and it is slightly larger in diameter than the last turn of the thread groove proximate the free end of the threaded base 22 of the bulb. The lock thread element 28 is loosely threadedly engaged onto the threaded base 22 proximate the free end of the latter, and generally in the last turn of the thread groove thereof, and then the base 22 of the bulb with the thread element 28 thereon is pushed down into the internally tapered front end portion of the anode shell 12 until the thread element 28 frictionally seats against the tapered inner surface 26 of the shell. This leaves the glass portion 20 of the bulb still spaced outwardly from the front end 14 of the shell 12. The glass portion 20 is then grasped and rotated so as to screw the light bulb 18 down into the fully seated position illustrated in FIGS. 1 and 3 of the drawings, wherein the glass portion 20 of the bulb seats against the front end 14 of the shell 12. As the bulb is thus screwed into its fully seated position, the lock thread element remains in a generally fixed axial position relative to the shell 12, being wedged against the tapered inner surface 26 thereof, and the external thread groove on the light bulb base 22 will advance in the lock thread element 28, the taper of the threaded base 22 causing increasingly tight wedging engagement of the lock thread element 28 against both the tapered inner shell surface 26 and the tapered threaded base 22, so as to provide good mechanical connection of the light bulb in the front end portion of the shell 12 and also good electrical connection between the outer terminal 22 of the bulb and the anode shell 12.
A hole 30 is provided through the wall of the cylindrical anode shell 12 in the front end portion of the shell but spaced rearwardly from the lock thread element 28. This hole 30 allows entrapped air and reaction gases to escape from the cell if the rear end 16 of the cell is immersed in water to activate the cell.
The cell 10 also includes an electrolyte layer 32 extending from the rear end 16 of the cylindrical shell 12 forwardly to a position somewhat short of the innermost end of light bulb 18, which is the center terminal 24 thereof, and also short of the hole 30. Electrolyte layer 32 is preferably in the form of a rolled sheet 34 of highly absorbent, porous insulation material that has been soaked in a saturated electrolyte solution and dried so as to carry a maximum of dried electrolyte therein. This sheet 34 of absorbent insulation material is rolled, preferably into several layers, after it has been filled with the dry electrolyte, and inserted into the cylindrical anode shell 12 from the rear end 16 thereof.
FIG. 7 illustrates a presently preferred construction of the absorbent sheet 34 which carries the dried electrolyte material, wherein the sheet 34 is of a foraminous or perforated character, being generally net-like with the absorbent web portions 36 and interstitial perforations 38. The web portions 36 are of a highly absorbent, porous, blotter-like consistency, and the material preferably has substantial resiliency in the direction normal to the flat surfaces thereof so that when it is rolled and in operative position within the cylindrical anode shell 12 it will assert a radial biasing effect between the inner and outer electrodes. A suitable perforated, resilient, absorbent insulation material for the sheet 34 is sold commercially as "Handi-Wipe".
The presently preferred electrolyte is an aqueous sodium chloride solution. The porous sheet 34 is immersed in a fully saturated water solution of sodium chloride, generally with an excess of the salt therein to assure saturation, and preferably at a solution temperature in the range of from about 100° F. to about 150° F., and then with the sheet 34 loaded with the solution, it is laid out on a flat, non-absorbent surface and dried. This leaves the absorbent web portions 36 of the sheet loaded with the dried salt, and also provides a considerable amount of dried salt in the interstitial perforations 38.
The highly absorbent nature of the sheet 34 causes the rolled sheet 34 operatively disposed in the cell 10 as best shown in FIGS. 3 and 4 to rapidly draw water through the entire body of the rolled sheet 34 when the rear end edge of the rolled sheet 34 is immersed in water or otherwise exposed to aqueous fluid. As the water is thus rapidly soaked up into the rolled sheet 34, the water dissolves the dried electrolyte therein to "turn on" the cell.
The inerstitial perforations 38 in the sheet 34 provide improved ion exchange characteristics when the cell is in operation, and also serve as receptacles for magnesium hydroxide flakes which tend to come off of the anode during operation of the cell so that such flakes do not seriously interfere with the ion exchange and hence the current flow from the cell.
The cathode is generally designated 40, and is preferably in the form of a rolled sheet 42 of silver halide material. The preferred silver halide is silver chloride, and this cathode material is "developed" according to conventional practice. A presently preferred sheet silver chloride material has a thickness of about 1/32 inch, and two layers of this sheet 42 in the roll thereof that forms the cathode 40, as best shown in FIGS. 3 and 4, will generally be satisfactory. Additional layers of the silver chloride in the roll will provide more operative time for the cell. The current capacity of the cell is determined principally by the amount of surface area of the outer surface of the silver chloride roll in the cell, as well as by the concentration of electrolyte and freedom of ion exchange permitted by the porous absorbent sheet material employed in the electrolyte layer 32. The rolled electrolyte-supporting sheet 34 and the rolled cathode sheet 42 are preferably co-extensive in length as best seen in FIG. 3.
Termination is preferably provided for the cathode 40 by means of a thin strip 44 of conductive material, which is preferably a strip of coined silver for compatability with the silver chloride cathode. The conductor strip 44 is soldered to the center terminal 24 of the light bulb 18, and extends rearwardly through the passage in the rolled, tubular cathode 40, being pressed outwardly into good electrical contact with the cathode 40 by means of a dielectric support tube 46 that is disposed within the rear end portion of the cathode 40.
Assembly of the cell 10 having the aforesaid components is simple and quickly accomplished. First, the cathode sheet 42 is rolled into its cylindrical shape, and then the porous sheet 34 that is impregnated with dried electrolyte is rolled around the tubular cathode, and this combination is pushed into the cylindrical anode shell 12 from the rear end 16 thereof. Next, the light bulb 18, with the lock thread element 28 on its threaded base 22 and with the conductor strip 44 soldered to its center terminal 24, is engaged in the front end portion of the anode shell 12 in the manner heretofore described in detail. As the light bulb 18 is brought toward the front end 14 of the shell 12, the free end portion of the conductor strip 44 is fed through the axial passage defined within the rolled cathode sheet, so that when the light bulb 18 is in its fully seated, attached position as best shown in FIG. 3, the conductor strip 44 will extend all of the way through the axial passage in the rolled cathode sheet 42, with a tail end portion of the conductor strip 44 extending out beyond the rear end 16 of the cell. This exposed free end of the conductor strip 44 is then simply bent over the rear end edge of the unit and held there while the support tube 46 of dielectric material is pushed into the axial passage defined within the rolled cathode sheet 42 from the rear end so as to clamp the conductor strip 44 against the inwardly facing surface of the cathode, as best shown in FIGS. 3 and 4. The exposed tail end of the conductor strip 44 may then be snipped off proximate the rear end of the cell, or a tail end portion of strip 44 may be tucked back forwardly into the inside of the support tube 46.
The rolled sheet 42 of the cathode provides a relatively rigid tubular structure, and it is preferably rolled to an OD such that with the desired number of rolled layers of the electrolyte-containing sheet 34, the sheet 34 will be slightly compressed in the radial direction so that its resiliency will provide a biased engagement between the cathode 40, electrolyte layer 32 and cylindrical anode shell 12.
FIG. 6 illustrates corrosion-inhibiting coatings 48 and 50 on the respective outer and inner surfaces of the magnesium anode shell 12. Actually, the corrosion-inhibiting coating is a continuous coating covering all surface regions of the magnesium anode shell 12. However, the coating portion 48 over the outer surface of the shell 12 is important as a protection against corrosive damage from handling and atmospheric effects; while the coating portion 50 over the inwardly facing surface of shell 12 is important because of the presence of the highly corrosive dried electrolyte, which would otherwise quickly render the inner, operative surface of the magnesium shell into a very poor electrical conductor, or generally non-conductive, which would prevent or seriously diminish operation of the cell. The inner corrosion-inhibiting coating 50 also helps to preserve good electrical contact from the inner surface of the shell 12 to the lock thread element 28, and hence to the outer terminal 22 of the light bulb 18.
The protective coating is provided by immersion of the magnesium shell 12 in a detergent bath consisting of a water detergent solution of controlled concentration, at a controlled temperature, and for a controlled period of time. Extensive tests conducted by the applicant disclose that all detergents in aqueous solution will cause some coating to appear on a magnesium surface. However, the general quality of the coating and the percentage of voids in the coating on a microscopic basis vary widely with different detergents, and also with different concentrations, temperatures and time durations of the treatment.
Because of the availability, the applicant has been required to perform the testing of the present method of producing the corrosion-inhibiting coating on the surface of the magnesium anode with commercial washing detergents. Such detergents all have a variety of additives to assist the detergent action in washing clothes, dishes or the like, or simply for advertising purposes, and such additives generally tend to detract from optimum performance of the detergent to provide the protective coating on the magnesium anode. Such additives include things like oils, fats, enzymes, phosphates, and the like, and even include peanut shells in at least one detergent preparation. Because applicant was required to use such commercial detergents during the performance of tests set forth hereinafter to determine suitable detergent baths, temperatures, and immersion times, the ratings which applicant has applied to the results of such tests as to quality of the coating and percentage of voids in the coating are not considered to be optimum. However, the applicant has found in conducting these tests that some of the commercial detergents do provide a corrosion-inhibiting coating of satisfactory quality and with a sufficiently low percentage of voids on a microscopic basis to be satisfactory for use in deferred action electric cells according to the present invention which contain the dried electrolyte material therein.
It is contemplated for optimum performance of the invention to provide a detergent without any of the usual additives of a commercial detergent so as to eliminate the deleterious effects of such additives during the forming of the corrosion-inhibiting coating on the magnesium anode.
In addition to the tests of various detergents to determine the magnesium coating capability thereof, applicant also attempted to produce similar coatings with the use of soap solutions. However, applicant determined with such tests that immersion of the magnesium anode in a soap solution does not produce any substantial protective coating thereon.
The test examples set forth hereinafter for various detergents were performed on magnesium AZ31B, in 0.030 inch thickness flat stock. Each example has a column designated "Quality of Coating" wherein the quality is rated as follows:
A--Excellent
B--Good
C--Fair
D--Not Desired
These quality ratings were determined in part by viewing the coated surfaces under a 3,000 power microscope, and include a consideration of such quality factors as thickness of the coating, durability of the coating, and amount of voids. It will be noted in the following test examples that with the use of commercial detergents the highest quality rating was B.
Each of the following test examples also has a column entitled "% Voids in Coating". This was determined by an inspection under a 3,000 power microscope, and the percentage figure given for each test is the percentage of the magnesium surface that is not coated on a microscopic basis.
Coatings which are rated A, B or C, and which have a percentage of voids no greater than about 25%, are generally acceptable coatings for use in deferred action electric cells according to the invention.
Generally, magnesium stock that will be employed for the anode of an electric cell according to the present invention will have an oil film coating in its off-the-shelf condition. Such oil coating must be removed from the magnesium in order for the magnesium to have the necessary conductivity for use in an electric cell. The detergent bath of the present invention quickly removes such oil film from the magnesium when the magnesium is first immersed in the bath, thereby cleaning the surface of the magnesium in preparation for the formation of the corrosion-inhibiting coating. Thus, the detergent bath has a two-step function in preparing the magnesium for use as an anode in the present invention.
If the magnesium to be coated has already become corroded or is too dirty, it is preferable to clean it with steel wool before immersing it in the detergent bath to provide the corrosion-inhibiting coating.
In the following test examples for various commercial detergents, a number of separate runs were made for each type of detergent. All of the detergent baths that were prepared employed 32 ounces of water, which in most cases was tap water, but in a few of the tests was distilled water, designated "Dist." in the following examples. The weight of the detergent dissolved in the water, whether it was a liquid detergent or a powdered or granulated type detergent, was measured in grams, and amounts of either 50 or 100 grams of detergent were employed. The temperatures of the detergent baths are given in the examples in degrees Fahrenheit, and these range from a minimum of 70° F. to a maximum of 180° F. The time duration of immersion of the magnesium is given in minutes, and ranges from a minimum of five minutes to a maximum of 120 minutes.
EXAMPLE 1______________________________________"FAB"Vol.Wa- Type Wt. QualityRun ter Wa- Deterg. Temp. Time of % VoidsNo. Oz. ter Grams °F. Min. Coating Coating______________________________________1 32 Tap 100 100 30 D 45%2 32 Tap 100 150 30 D 45%3 32 Tap 100 180 30 D 90%4 32 Tap 50 100 30 D 30%5 32 Tap 50 150 30 D 25%6 32 Tap 50 180 30 D 70%7 32 Tap 100 80 30 C 5%8 32 Tap 100 90 30 D 25%9 32 Tap 100 180 45 D 90%10 32 Tap 50 70 60 C 2%11 32 Tap 50 70 90 D 2%12 32 Tap 50 70 120 D 95%13 32 Dist. 50 150 15 D 30%14 32 Dist. 50 150 30 D 30%15 32 Dist. 50 150 90 D 20%______________________________________
The coatings produced in runs 7 and 10 in Example 1 were satisfactory corrosion-inhibiting coatings according to the invention. It is to be noted that with "FAB" as the detergent, the best results were achieved at relatively low temperatures, on the order of 70° F. to 80° F. "FAB" is a product of Colgate-Palmolive Co., New York, N.Y. 10022.
EXAMPLE 2______________________________________"TIDE"Vol. Type Wt. Quality % VoidsRun Wa- Wa- Deterg. Temp. Time of inNo. ter ter Grams °F. Min. Coating Coating______________________________________1 32 Tap 100 100 30 D 30%2 32 Tap 100 150 30 D 30%3 32 Tap 100 180 30 D 30%4 32 Tap 100 100 15 B 1%5 32 Tap 100 70 30 B 0%6 32 Tap 100 80 30 B 0%______________________________________
The coatings produced in Runs 4, 5 and 6 in Example 2 were very good corrosion-inhibiting coatings according to the invention. It is to be that the best results with "Tide" are at low temperatures, on the order of 70° F. to 80° F., but that good results are still obtainable up to about 100° F. if the time is materially reduced. "Tide" is a product of Proctor & Gamble, Cincinnati, Ohio 45202.
"FAB" and "Tide" as used in respective Examples 1 and 2 were powdered detergent products.
EXAMPLE 3______________________________________"AJAX"Vol.Wa- Type Wt. Quality % VoidsRun. ter Wa- Deterg. Temp. Time of inNo. Oz. ter Grams °F. Min. Coating Coating______________________________________1 32 Tap 50 130 15 B 0%2 32 Tap 50 150 15 B 1-2%3 32 Tap 50 150 30 B 3-4%______________________________________
The "Ajax" detergent employed in Example 3 was a liquid dishwashing detergent. All three of the runs made with "Ajax" detergent provided very good corrosion-inhibiting coatings on the magnesium anode material, with Run No. 1 producing the best of these three coatings. It is to be noted that good coatings are produced with "Ajax" liquid dishwashing detergent at relatively high temperatures (130° F. to 150° F.) as compared with the temperatures that produce the best coatings with "FAB" and "Tide" (70° F. to 80° F.). "Ajax" liquid dishwashing detergent is a product of Colgate-Palmolive Co., New York, N.Y. 10022.
EXAMPLE 4______________________________________"AXION"Vol.Wa- Type Wt. Quality % VoidsRun ter Wa- Deterg. Temp. Time of inNo. Oz. ter Grams °F. Min. Coating Coating______________________________________1 32 Tap 100 100 30 D 5%2 32 Tap 50 100 30 D 50%3 32 Tap 100 150 30 D 35%4 32 Tap 50 150 30 C 20%5 32 Tap 100 180 30 D 25%6 32 Tap 50 180 15 C 10%7 32 Dist. 100 100 15 D 25%8 32 Dist. 100 100 30 D 40%______________________________________
The coating produced in Runs 4 and 6 in Example 4 were satisfactory corrosion-inhibiting coatings according to the invention, although not as good as the coatings produced in some of the runs in Examples 1, 2 and 3. It is noted that "Axion" requires relatively high temperatures for a fair quality coating (150° F. to 180° F.). "Axion" is a product of Colgate-Palmolive Co., New York, N.Y. 10022.
EXAMPLE 5______________________________________"DASH"Vol.Wa- Type Wt. Quality % VoidsRun ter Wa- Deterg. Temp. Time of inNo. Oz. ter Grams. °F. Min. Coating Coating______________________________________1 32 Tap 100 100 30 D 50%2 32 Tap 50 100 30 D 50%3 32 Tap 100 150 30 D 30%4 32 Tap 50 150 30 C 20%5 32 Tap 100 180 30 C 10%6 32 Tap 100 180 15 D 20%______________________________________
The coatings produced in Runs 4 and 5 in Example 5 were satisfactory corrosion-inhibiting coatings according to the invention. It is to be noted that relatively high temperature (150° F. to 180° F.) were required. It is also interesting to note that a reduction in the concentration of detergent at 150° F. produced a better coating. "Dash" is a product of Proctor & Gamble, Cincinnati, Ohio 45202.
EXAMPLE 6______________________________________"ALL"Vol.Wa- Type Wt. Quality % VoidsRun ter Wa- Deterg. Temp. Time of inNo. Oz. ter Grams °F. Min. Coating Coating______________________________________1 32 Tap 100 100 30 C 5%2 32 Tap 100 150 30 B 5%3 32 Tap 100 180 30 D 40%4 32 Tap 50 100 30 D 35%5 32 Tap 50 150 30 C 10%6 32 Tap 50 180 30 D 15%______________________________________
Runs 1, 2 and 5 in Example 6 produced satisfactory corrosion-inhibiting coatings according to the invention. It is to be noted that good results were produced at both 100° F. and 150° F., but the amount of detergent could be reduced at the higher temperature. "All" is a product of Lever Brothers, New York, N.Y. 10022.
Examples 4, 5 and 6, for "Axion", "Dash" and "All", respectively, involved the use of powdered detergents.
EXAMPLE 7______________________________________"PERFORM"Vol.Wa- Type Wt. Quality % VoidsRun ter Wa- Deterg. Temp. Time of ofNo. Oz. ter Grams °F. Min. Coating Coating______________________________________1 32 Tap 100 100 15 D 90%2 32 Tap 100 100 30 D 90%3 32 Tap 100 150 15 D 90%4 32 Tap 100 150 30 D 90%5 32 Tap 100 180 15 D 90%6 32 Tap 100 180 30 C 5%______________________________________
The coating produced in Run 6 in Example 7 was a satisfactory corrosion-inhibiting coating according to the invention. The "Perform" used was a liquid detergent product manufactured by Paramount Chemical Corp., Montebello, Calif. 90640. It is to be noted that "Perform" required a high temperature (180° F.) and substantial time (30 minutes) to provide such satisfactory coating.
EXAMPLE 8______________________________________"SPRINGFIELD"Vol.Wa- Type Wt. Quality % VoidsRun ter Wa- Deterg. Temp. Time of ofNo. Oz. ter Grams °F. Min. Coating Coating______________________________________1 32 Tap 100 100 30 C 2%2 32 Tap 100 150 5 C 2%3 32 Tap 100 180 7 D 15%4 32 Tap 50 100 40 C-B 0%______________________________________
The coating produced in Runs 1, 2 and 4 in Example 8 were satisfactory corrosion-inhibiting coatings according to the invention. It is to be noted that "Springfield" works satisfactorily at relatively low temperature (100° F.) and also relatively high temperature (150° F.). "Springfield" is a product of Certified Grocers, Los Angeles, Calif. 90022. This was a powdered detergent product.
EXAMPLE 9______________________________________"LAMWAY SA8"Vol.Wa- Type Wt. Quality % VoidsRun ter Wa- Deterg. Temp. Time of ofNo. Oz. ter Grams °F. Min. Coating Coating______________________________________1 32 Tap 100 80 30 D 100%2 32 Tap 100 80 60 D 100%3 32 Tap 100 80 120 D 80%4 32 Tap 100 150 15 D 95%5 32 Tap 100 150 30 D 95%______________________________________
None of the coatings produced in the test runs made on "Amway SA8" were satisfactory corrosion-inhibiting coatings according to the present invention, regardless of wide variations in times and temperatures. This was a powdered detergent.
It will be apparent from the foregoing examples that the various commercial detergents differ widely in their ability to provide satisfactory corrosion-inhibiting coatings on magnesium, and in the bath temperatures and immersion times required to provide satisfactory coatings. A general observation is that with an increase in the bath temperatures, the dwell time of the immersion can be generally reduced.
These corrosion-inhibiting coatings produced by immersion of the magnesium anode material in suitable detergent baths do not materially diminish the surface conductivity of the magnesium in the coated area, despite the greatly reduced chemical activity of the exposed surfaces. Thus, in providing the novel coating according to the present invention, the electrical conductivity of the anode material is not only preserved at the time of coating, but is preserved by the coating over a prolonged shelf life period, which may be on the order of a number of years.
Referring now particularly to FIGS. 9 to 12 of the drawings, these figures illustrate a survival lamp unit generally designated 52 which is adapted to be dropped into a body of water as a floating signal light. This survival lamp unit 52 comprises generally a cylindrical can-like container 54 having a light transmitting dome 56 of transparent or translucent material, preferably plastic, projecting upwardly from the upper end of the cylindrical container 54. The container 54, although of any can-like construction, is preferably similar to the conventional frozen juice can, and includes a cylindrical shell 58. A top wall disc 60 is peripherally crimped to the upper end of the cylindrical shell 58, and has a threaded socket 62 centrally formed therein. The socket 62 preferably projects downwardly from the generally planar surface of the top wall disc 60, and is adapted to threadedly receive therein the outer terminal 22 of light bulb 18. This positions the glass portion 20 of light bulb 18 above the top wall disc 60 and within the light transmitting dome 56, so that light radiated from the bulb 18 will be transmitted through the dome 56 both directly from the bulb and by reflection off of the upper surface of the disc 60 which is preferably a reflective metal surface.
A pair of bracket arms 64 are connected to disc 60 by rivets 66 or other suitable means, the arm 64 extending downwardly to spaced lower end portions that are engaged in diametrically opposed relationship against opposite sides of the upper end portion of cylindrical shell 12, shell 12 being secured in this position by means of a non-conducting rivet 68 extending transversely through the bracket arm 64 and shell 12. By this means the deferred action cell 10 is suspended centrally within the cylindrical container 54, in generally coaxial relationship, with the front end 14 of the cell disposed immediately below and adjacent to the light bulb 18, and the rear end 16 of the cell disposed generally in a lower portion of the container 54. The outer terminal 22 of light bulb 18 is electrically connected through threaded socket 62, top wall disc 60 and metal bracket arms 64 to the anode shell 12 of the electrical cell 10. The center terminal 24 of the light bulb 18 is electrically connected through the conductor strip 44 in the manner heretofore described in connection with FIGS. 3 to 5 of the drawings to the cathode 40 of the cell 10. By providing the rivet 68 of non-conductive material, there is no danger of short-circuiting the cathode conductor 44 to anode shell 12.
While a single deferred action electric cell 10 is shown centrally disposed in the cylindrical container 54, it is to be understood that if desired a plurality of such cells 10 may be arranged in side-by-side relationship within the container 54 if it is desired to extend the operational time of the lamp.
A metal bottom wall 70 is peripherally crimped to the bottom edge of the cylindrical shell 58 so as to provide a hermetically sealed cavity inside of the cylindrical container 54 for maximum shelf life of the entire unit, and particularly of the deferred action electric cell 10 therein. This bottom wall 70 has a removable disc portion 72 thereof comprising substantially the entire bottom wall. The removable disc portion 72 is defined by a tear line or score line 74, and a pull tab 76 attached to the removable disc portion 72 provides a means for tearing out substantially the entire bottom wall of the container 54.
While the top wall disc 60 may not provide a hermetic seal for the region of the cell 10, the peripheral portion of the top wall 60 is sealed to the upper edge of the cylindrical shell 58, and the lower edge of light transmitting dome 56 is sealed to the peripheral part of top wall 60, as by heat sealing or other suitable means, to provide the hermetic seal at the upper end of the container 54.
Despite the extended shelf life of the survival lamp unit 52, the unit is ready for virtually instantaneous operation by simply grasping the pull tab 76 and ripping out the removable disc portion 72 to substantially completely open up the lower end of the cylindrical shell 58. Then the unit is simply tossed into the water, and the water will freely enter the open lower end causing the lower end to drop down into the water, and air captured in the upper portion will cause the unit to float in its upright position with the light transmitting dome 56 above the water. In this position the rear end 16 of the cell 10 will be immersed in the water, causing almost instantaneous activation of the cell and illumination of the light bulb 18.
To assure that the unit 52 will float at the desired level and in an upright position, it is preferred to provide a hole 78 through the upper portion of the cylindrical shell 58 that is spaced downwardly from the top wall 60 and normally sealed by a plug or cover member 80 that is removable from the hole 78 from the inside. Such sealing means 80 is connected to the removable bottom disc portion 72 by a suitable link member 82 so that when the disc portion 72 is torn out to prepare the unit for use, the sealing means 80 will be automatically removed from the hole 78. This relieves excess gas, both air and reaction gas from below the hole 78, but provides a flotation chamber having gas therein above the hole 78 for stabilized flotation of the unit at a controlled level.
While the present invention has been shown and described herein in what are conceived to be the most practical and preferred embodiments, it is recognized that departures may be made therefrom within the scope of the invention, which is therefore not to be limited to the details disclosed herein. | A deferred action electric cell of the type having a magnesium anode and a silver halide cathode, wherein the electrolyte is supported in dried form intermediate the electrodes for rapidly developing full electrical potential upon the addition of any aqueous fluid, even fresh water. A novel method of coating the magnesium anode utilizing a detergent bath produces a coating that prevents corrosive deterioration of the magnesium from handling and from close proximity of the dried electrolyte, for an extended shelf life. One form of survival lamp embodying the cell utilizes the tubular magnesium anode as the body of the lamp, with a light bulb seated in one end thereof and the other end open for introduction of activating water; while another form adapted to be dropped into a body of water as a floating signal light has the cell sealed inside of a can-like cylindrical container having a light-transmitting dome at the top and a bottom adapted to be torn out along a tear line to expose the cell prior to dropping the unit into the water. | 5 |
RELATED APPLICATIONS
This application is a continuation of pending application, U.S. Ser. No. 13/016,081, entitled SURGICAL AIMING DEVICE, filed Jan. 28, 2011, the entire teaching, disclosure and contents of which are incorporated herein by reference by in their entirety.
BACKGROUND
Reconstructive bone and ligament surgery often involves drilling into skeletal members to attach connective elements such as ligament and tendon grafts, as well as various artificial replacements and/or attachments for articulated joints. In particular, reconstructive surgery involving the anterior cruciate ligament (ACL) is becoming particularly significant because the effectiveness of reconstruction can have a profound effect on the subsequent athletic ability of the patient. For professional athletes, for example, an effective ACL repair can salvage an otherwise career ending injury. Similarly, an improperly treated ACL injury can be a permanent detriment even to an amateur athlete.
SUMMARY
Reconstructive surgery involving functional, structural fixation to bone members often involves drilling into a structurally sound area of the corresponding bone. In an ACL repair, antegrade drilling of the femur is becoming more common. A damaged ACL is often replaced with a graft from a patellar tendon or a semitendinosus tendon. Such a repair is facilitated by tunnels formed in the tibia and femur for use in implanting the graft in the patient's knee. Recent studies suggest more accurate placement is achievable by such antegrade femoral drilling than by conventional approaches such as drilling the femoral tunnel through the tibial tunnel. The graft may then be secured in the tunnels by fixation means, such as, for example, interference screws or sutures tied to screw posts. The femur, in particular, is often subjected to more substantial forces because it often bears the entire weight of the patient, and being the largest human bone, may be relied upon to accommodate a substantial connective force from a surgically added structure.
Configurations herein are based, in part, on the observation that conventional arrangements for surgical or arthroscopic drilling rely on a fixed aimer that may impede positioning of the handle and insertion guide for optimal positioning of a drill hole at an insertion point. An optimal placement defines a point of entry for a drilling hole that displaces minimal soft tissue depth while engaging a rigid structure (such as a knee bone) at a structurally sound location. Conventional approaches using such a fixed, rigid aimer hinder the ability to achieve optimal interarticular tunnel placement.
In ACL reconstruction involving such drilling, therefore, attachment of structural surgical tethers, such as grafts and artificial connectors, should be performed at a structurally sound location on the femur. Configurations herein disclose a drilling guide adapted for positioning a drilling tunnel in (ACL) reconstruction. Typically, a drilling guide adapted for insertion into a joint region locates a drilling exit point, while a surgeon manipulates the handle of the drilling guide to locate an entry location. Unfortunately, conventional arrangements suffer from the shortcoming that drilling guides for directing placement of the drilled hole are universal, in that a single straight design having a fixed relation of an aimer arm and a handle identify a point of drilling. Conventional approaches, therefore, do not distinguish a left from right knee, nor individual differences in the bone configuration of an individual patient, which compromises the ability to manipulate the drilling guide to pivot around the aimer arm for locating an optimal entry point for drilling. Conventional mechanisms employ a fixed aimer incapable of rotational or pivoting movement around a hinge connection to the arm denoting the drilling exit point. Such arrangements may attempt a similar range of application by employing fixed left and right guides, or a series of fixed angle guides for both right and left application, however this would result in a trial and error administration as well as requiring manufacturing of a range of multiple fixed angle guides.
Configurations herein substantially overcome the above described shortcomings by employing a hinged pivoting guide for positioning a femoral or tibial tunnel, for example, in anterior cruciate ligament (ACL) reconstruction. Locating the drilling hole for placement of the tunnel optimally penetrates a minimal depth of soft tissue (skin, muscle, etc.) yet directs drilling into a sufficiently rigid and structurally sound area of the femur. The hinged guide allows placement of an aimer point at a desired drilling exit location on the femur. The handle includes an aperture indicative of the drilling location, and a surgeon may manipulate the handle by pivoting around the hinge to dispose the aperture at an optimal location while maintaining the same exit location defined by the aimer point. In this manner, an optimal drilling location is selectable by positioning the handle to an area of minimal soft tissue depth and in line with a structurally sound path through the femur.
In further detail, the surgical aiming device as disclosed herein includes a handle coupled to a proximate end of an elongated arm, in which the elongated arm further has a distal end, and a hinge securing an aimer to the distal end for rotational communication around a hinge axis. The aimer has an elongated aimer tip and an aimer point, such that the aimer point is at a distal end of the aimer tip from the hinge, and the aimer tip couples to the arm via the hinge at a proximate end. The hinge is adapted to secure the aimer at a degree of rotation about an axis defined by the hinge rotation, such that the axis passes through the aimer point throughout rotation of the hinge while maintaining the aimer point in line with an insertion guide slideably movable through the aperture in the handle, in which the aperture defines an insertion axis extending toward the aimer point such that the aimer point remains disposed at the intersection of the hinge axis and the insertion axis.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features and advantages of the invention will be apparent from the following description of particular embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1 shows a side view of the surgical aiming device as disclosed herein;
FIG. 2 shows a perspective view of the surgical aiming device of FIG. 1 ;
FIG. 3 shows a side view of the surgical aiming device as in FIG. 1 with a partially extended arced section;
FIG. 4 shows an opposed side view of the surgical aiming device of FIG. 1 ;
FIG. 5 shows an alternate view of the surgical aiming device of FIG. 4 having a partially extended arced section and disengaged arm;
FIG. 6 shows a perspective view of the aimer arm disposed at a surgical site;
FIG. 7 shows an exploded view of the arm of FIG. 1 ; and
FIGS. 8-9 show a procedural sequence employing the surgical aiming device of FIG. 1 .
DETAILED DESCRIPTION
Disclosed below is an example configuration and deployment of the surgical aimer arm. In an example arrangement, an ACL repair employing the surgical aiming device for femoral drilling is shown. Alternate configurations may employ placement on other skeletal structures, or on softer tissue surfaces, and may or may not employ a drilling approach for excavating the insertion tunnel for a guidewire.
FIG. 1 shows a side view of the surgical aiming device 100 including a handle 102 having a slot 104 defining an arc 106 . The handle 102 is shaped for a secure grasp by a surgeon or other operator. An arm 110 has an arced section 112 and a straight section 114 . The arced section 112 is shaped to slideably engage with the slot 104 in the handle 102 for movement according to arrow 116 . The straight section 114 has a hinge 120 for securing an aimer 130 to the straight section 114 at the opposed end distal from the arced section 112 . The hinge 120 adapts the aimer 130 for rotational communication with the straight section 114 around a hinge axis 122 , as shown by arrow 124 . The hinge 120 secures the aimer 130 via a screw 126 or other suitable pivotal coupling around the hinge axis 122 .
The aimer 130 includes an elongated aimer tip 132 extending from the hinge and an aimer point 134 at a distal end of the aimer tip 132 from the hinge 120 . The aimer tip 132 couples to the straight section 114 via the hinge 120 at a proximate end. The handle 102 further includes an insertion guide 140 adapted for slideable movement within an aperture 144 in the handle 102 along an insertion axis 142 . The insertion guide 140 has slanting teeth 146 for selective ratcheting engagement with a pawl 148 when the insertion guide 140 is rotated via an insertion knob 149 such that the teeth 146 engage the pawl 148 . The insertion axis 142 passes through the aimer point 134 at an intersection 150 of the hinge axis 122 , thus the aimer tip 132 extends such that the aimer point 134 is disposed on the insertion axis 142 throughout the range of rotation 124 of the aimer 130 .
The arm 110 is adapted for arcuate movement relative to the handle 102 as defined by the arc 106 , shown by arrows 116 . The aimer point 134 is the center of a circle defining the arc 106 in the handle 102 through which the arced section 112 slideably engages, thus the aimer point 134 retains its position at the intersection 150 during the arcuate movement 116 . Further, as the hinge 120 is adapted to secure the aimer 130 at a degree of rotation about an axis 122 defined by the hinge 120 and passing through the aimer point 134 , the aimer point remains at the intersection 150 throughout movement of the arm 130 and arced section 112 .
The insertion guide 140 has a hollow core ( 176 , FIG. 6 below) for subsequent guidewire access, discussed further below. A taper, serration, or other suitable engaging edge on the tip 141 of the insertion guide facilitates identification of an incision point, and subsequently for engaging a bone or other hard surface for fixing the insertion guide for the guidewire. Typically a soft tissue incision is made where the tip 141 contacts soft tissue, the insertion guide 140 inserted until hard material (i.e. bone) is encountered, and the tip engages the bone facilitated by the ratcheting action to avoid slippage during guidewire insertion.
FIG. 2 shows a perspective view of the surgical aiming device of FIG. 1 . Referring to FIGS. 1 and 2 , the handle 102 includes apertures 103 for weight reduction. The insertion guide 140 is extendable to the aimer point 134 to define a drilling and/or insertion hole for a guide wire along the insertion axis 142 through a range from the aperture 144 in the handle to the aimer point 134 . A pivot knob 127 rotates the hinge screw 126 (arrow 125 ) for securing and releasing the hinge 120 at various degrees of rotation (pivot) through a range, shown at a pivot angle 124 . The arced section 112 is fixable by fixation knob 113 .
FIG. 3 shows a side view of the surgical aiming device as in claim 1 with a partially extended arced section 112 . Referring to FIGS. 1 and 3 , the arced section 112 is partially extended exposing the apertures 103 in the handle 102 . The insertion axis 142 and hinge axis 122 still intersect 150 at the aimer point 134 , since the arm 110 travels along an arc 116 on the circle 152 with the aimer point 134 at the center.
FIG. 4 shows an opposed side view of the surgical aiming device of FIG. 1 . Referring to FIGS. 1 and 4 , the aperture 144 in the handle is visible showing the slanting teeth 146 providing ratcheting movement to the insertion guide 140 . The hollow core 176 of the insertion guide 140 allows passing of a guidewire 154 ( FIG. 6 , below) through an insertion tunnel 174 formed from rotation of the insertion guide 140 or from a separate drilling device.
FIG. 5 shows an alternate view of the surgical aiming device of FIG. 4 having a partially extended arced section 112 and disengaged arm 130 . The partial extension of the arced portion 112 of the arm 110 is shown by the apertures 103 only partially obscured by the arced portion 112 . The hinge 120 employs the securing screw 126 for securing the arm 130 , shown detached with a threaded portion of the securing screw 126 visible.
FIG. 6 shows a perspective view of the surgical device 100 disposed at a surgical site. As indicated above, ACL repairs often involve surgical drilling through the femur 160 and tibia 162 for passing a guidewire 154 through the insertion guide 140 . Referring to FIGS. 1 and 6 , an example of using the surgical aiming device 100 for such an application is shown. The surgeon disposes the aimer point 134 at a target location 170 within the surgical site, such as an anatomically sound location on the femur 160 . Typically this would be the same location as the prior attachment of the ligament being repaired, but other suitable locations may be marked/aimed. The surgeon frees the securing mechanism of the hinge 120 such as by loosening the hinge knob 127 , and disposes the arm 110 and handle 102 to a suitable location for drilling as defined by an incision point and corresponding drilling site 172 (note that the incision point often defines a soft tissue location along the insertion axis for insertion of the insertion guide towards the drilling site 172 ). A serrated or tapered edge at the tip 141 of the insertion guide 140 passes soft tissue, and contacts the drilling site 172 at the bone, cartilage, or other hard surface. The tip 141 is formed so as to engage the bone surface after penetrating the soft tissue through the insertion, and may be a pyramidal, serration, or tapered edge, for example. A drill may subsequently be employed to further excavate an insertion tunnel 174 , formed from the guide wire 154 passing through the hollow core 176 of the insertion guide 140 .
FIG. 7 shows an exploded view of the arm 110 of FIG. 1 , showing tick markings 113 metering arcuate extension of the arced portion 112 , and the separation of the hinge 120 rotationally securing the straight portion 114 of the arm 110 to the aimer 130 .
FIGS. 8-9 show a procedural sequence employing the surgical aiming device of FIG. 1 . Referring to FIGS. 1 and 8 - 9 , locating an optimal insertion point allows locating the aimer point 134 at a target location, and manipulating the handle 102 via pivoting of the hinge 120 and sliding the arced section 110 to dispose the insertion guide 140 accordingly, as follows.
A method for surgical drilling using the surgical aiming device disclosed herein includes, at step 200 engaging a handle 102 having a slot 104 defining an arc 106 in a surgical field for defining a drilling hole 174 by disposing an arm 110 having an arced section 112 and a straight section 114 , such that the arced section 112 slideably engages with the slot 104 in the handle 110 for arcuate movement therein, as depicted at step 201 .
The arm 110 hingedly attaches to the aimer 110 having an elongated aimer tip 132 and an aimer point 134 , such that the aimer point 134 is at a distal end of the aimer tip 132 from the hinge 120 , and the aimer tip 132 couples to the straight section 114 via the hinge 120 at a proximate end, as disclosed at step 202 .
An operator pivots the hinge 120 securing the aimer 130 to the straight section 114 distal from the arced section 112 for rotational communication with the straight section 114 around a hinge axis 122 , as shown at step 203 . The hinge axis 122 passes through the aimer point 134 throughout a range of motion 116 of the arced section 112 through the slot 104 , as depicted at step 204 . The aimer point 134 remains defined by the center of a circle 152 defining the arc 106 in the handle through which the arced section 112 slideably engages, as disclosed at step 205 . The surgeon or operator disposes, via the pivoting, the aimer tip 134 at a placement point 170 along the axis 142 defining an insertion path, as shown at step 206 . The hinge 120 is adapted to secure the aimer 130 at a degree of rotation 124 , such that the degree of rotation 124 is about an axis 122 defined by the hinge 120 and passing through the aimer point 134 , as depicted at step 207 . The hinge axis 122 is defined by a securing mechanism, such that the rotational communication 124 is about the axis 122 defined by the securing mechanism, and the degree of rotation 124 is fixable by the securing mechanism, as shown at step 208 . In the example arrangement, the securing mechanism is provided by the securing screw 126 and knob 127 , however alternate securement arrangements may be employed.
The operator or surgeon disposes the insertion guide 140 , such that the insertion guide 140 is slideably movable through an aperture 144 in the handle 110 . The aperture 144 defines an insertion axis 142 extending toward the center of a circle 152 defined by the arc 106 , as disclosed at step 209 . This includes, at step 210 , wherein the aperture 144 axis passes through the aimer point 134 , as the insertion guide 140 is disposed toward the aimer point 134 . This allows marking and fixing, via the edge at the tip 141 of the insertion guide 140 , an optimal insertion point 172 . The optimal insertion point 172 lies on the insertion axis where the insertion guide 140 meets bone, and the edge of the tip 141 allows fixing the insertion guide 140 against the bone for guidewire 154 insertion. The hinge axis 122 and the insertion axis 142 therefore define a placement point 170 representative of an optimal insertion point on the insertion axis 142 for surgical entry, in which the aimer point 134 of the arm disposed at the placement point 172 (target location), as depicted at step 211 .
While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application as defined by the appended claims. Such variations are intended to be covered by the scope of this present application. As such, the foregoing description of embodiments of the present application is not intended to be limiting, the full scope rather being conveyed by the appended claims. | A hinged pivoting guide for positioning a femoral tunnel in anterior cruciate ligament (ACL) reconstruction locates a drilling hole for placement that optimally penetrates a minimal depth of soft tissue (skin, muscle, etc.) yet directs drilling into a sufficiently rigid and structurally sound area of the femur. The hinged guide allows placement of an aimer point at a desired drilling exit location on the femur. The hinge is adapted to secure the aimer at a degree of rotation about an axis defined by the hinge rotation, such that the axis passes through the aimer point throughout rotation of the hinge while maintaining the aimer point in line with an insertion guide slideably movable through the aperture in the handle, the aperture defined by an insertion axis extending toward the aimer point such that the aimer point remains disposed at the intersection of the hinge axis and the insertion axis. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
Our invention is in the field of electroexplosive devices or "initiators," and has particular application in the initiators known as "squibs"--as distinguished from detonators and primers, which differ mostly in having greater explosive energy.
The present invention is directed to rendering a squib or other initiator substantially insensitive to stray radio-frequency electromagnetic fields in the ambient surrounds, and also to electrostatic charge accumulated by ambient phenomena, so that the squib reliably responds only to applied signals of the design voltage and wattage.
This invention has principal application in squibs having two connection terminals and an electrically isolated casing, but as explained below can be used to advantage under certain circumstances in a "coaxial" squib--the type in which the casing forms one electrical terminal.
2. Prior Art
Many theories have been advanced for the observed tendency of initiators, on occasion, to ignite without deliberate signal application, and in response to those theories many squib designs have resulted purportedly eliminating such spurious ignition.
Indeed inadvertent ignition seems to have been eliminated by a number of squib designs, but only by incorporation of features which are unacceptable in one or another application. In some instances accidental ignition is eliminated in a particular application or in particular types of circumstances but not in others.
Thus a considerable array of specialized squibs has been developed, in which design complexity, production cost, size, electrical and explosive characteristics, materials of construction, and reliability of firing in response to intentionally applied signals--as well as reliability of nonfiring in the absence of such intentionally applied signals--are mutually traded off to best advantage for particular applications.
The instant invention is a response to a specialized application wherein many of the most-stringent constraints of prior applications are present in combination, and so is in a sense a highly specialized squib. However, it is sufficiently easy and economical of manufacture and use to be an acceptable substitute for many initiators whose constraints are not so severe. In this sense, therefore, the present invention may be considered to constitute an advantageous "general-purpose," though not "universal," squib.
The simplest prior-art squib design, and ironically one of the most reliable designs as to RF-insensitivity, is the single-pin "coaxial" or "coax" type mentioned earlier. Such a squib consists of a generally cylindrical case having a generally coaxially mounted terminal, and a heater wire, called a "bridge" or "bridgewire," (or other heater structure) electrically connected between the terminal and case and in thermal contact with the explosive charge, be it pyrotechnic or higher-power explosive material. When used with pyrotechnic material (as opposed to primary-explosive powder) such a design is relatively insensitive to ignition by RF-induced sparks, because RF-induced voltages between pin and case are leaked off in the form of low-amperage current through the bridgewire. Much higher current levels are required to achieve the high temperatures at which pyrotechnic (metal and oxidant) formulations ignite.
There are, however, two limiting characteristics of the coax squib. First, it should not be a foregone conclusion that RF voltages always leak off across the bridge structure to the case, as this is a matter which involves the impedance of the particular bridge structure over an enormous range of RF frequencies as well as nearly unlimited variability in the orientation, polarization and power level of stray RF fields. Under just certain operating conditions it may be possible for an RF field to excite a coax-squib bridge at a frequency for which the bridge--in its squib-casing environment--is not a low impedance at all, but a very high impedance. Under these circumstances the fields may well result in an RF discharge which bypasses the bridge, igniting the explosive charge. It will be recalled that a small straight wire acts as an inductor, not a short, to radio-frequency power. It is entirely conceivable that such a wire in a particular orientation in a particular coax casing could form a tuned resonant circuit to RF power of a particular frequency, standing off the voltage and producing ignition as described above. Such phenomena may become even more likely where elaborate special geometries are employed to solve special problems in coax squibs.
For example, U.S. Pat. No. 3,867,885, assigned to Dynamit Nobel Aktiengesellschaft represents a very elaborate coax squib in which the bridge structure is metal plated or coated on an insulating disc, rather than being an initially integral wire. Thus the bridge has an exceedingly thin but relatively wide cross-section. It is disposed from a central pin or plated-through cavity radially to an annular contact ring created by the same process. At the other end of the central pin or central plated-through cavity is a circular metal disc likewise plated or coated on the bottom of the insulating disc. The insulating disc carrying the metal plated disc is placed in contact with a massive cylindrical "pole piece" which nearly surrounds the disc and plated bridge structure. A metal washer above the insulating disc makes contact with the annular contact ring previously mentioned. It would be virtually impossible to ascertain the response of this structure to all RF frequencies and field orientations which might be encountered under actual operating conditions, especially considering modifications of the thin plated-on structure which might preliminarily be caused by high-power RF fields. Thus the device is not in fact guaranteed RF-proof.
It may be noted in passing that the device of U.S. Pat. No. 3,867,885 incorporates a cup-shaped device bearing superficial similarity to a structure in a preferred embodiment of the instant invention. However, the cup-shaped device in the referenced patent is directly attached electrically to the squib casing, with no spark gap, and cannot function in the way or for the purpose described hereunder for the similar-appearing structure of the instant invention.
The second limitation of coax squibs is their susceptibility to inadvertent ignition due to an entirely different kind of accident:
Normally the case of a coax squib is placed at chassis ground of the weapon, spaceflight module, vehicle or other apparatus in which it is used, by gripping in a simple grounded receptacle. The firing signal then is applied with respect to chassis ground. The problem is that the squib can be fired by accidental touching of numerous other "hot" wires in the apparatus to the squib terminal or its signal wire, at any point in the apparatus. This can occur, for example, by a hand tool falling across two points in the circuit--or, perhaps more seriously, by a portion of the apparatus structure coming loose or sagging or being bent by unanticipated external impacts, so as to short a hot wire to the squib signal line. Just such sensitivities as this make coax squibs unacceptable in, for example, automotive air-bag inflators--where many years of use in automotive environments may readily cause just such accidents to occur.
Applications such as equipment deployment in high-reliability spaceflight vehicles, or the automotive air-bag inflator just mentioned, have given rise to the two-pin squib with floating case, in which the firing signal may be applied through an electrically isolated, floating circuit encompassing the two squib terminals. Even if the circuit is not completely "floated," a relative insensitivity to contact with the normal "hot" wires of nearby circuits can be obtained by judicious selection of voltage levels for the two signal wires to the squib.
Two-terminal, floating-case squibs may be typified by that in FIG. 1A of U.S. Pat. No. 3,783,788, assigned to Nippon Oils and Fats Company Ltd. of Tokyo. In two-terminal squibs the bridgewire, or some other igniting device, is connected between the two terminals rather than between a terminal and the case. Such devices are suggested as well by the prior-art schematic presented as FIG. 1 hereof: the case 11 has mounted within it two terminals 22 and 23, and bridgewire 21. The comments above relating to leakage across the bridgewire (from terminal to case in a coax squib) are applicable here as well (from terminal to terminal) in a two-terminal squib. That is to say, RF sparking between the terminals or pins 22 and 23 is relatively unlikely because voltage tends to be leaked off across the bridgewire--but is still possible inasmuch as the bridge structure in its squib-case environment may form a high impedance for certain RF fields, leading to a spark paralleling the bridge. In the two-terminal squib, however, there is an entirely new problem of RF arcing between either terminal 22 or 23 and the case 11, much more severe than in the coax squib, because normally there is no current leakage path to the case: by definition, the case is floating. If neither electrostatic nor radio-frequency energy is dissipated by low-current leakage, sufficient voltage of either sort can develop to cause a spark discharge within the case, as at 31 (FIG. 1), or at an externally provided safety spark gap 32, formed between one terminal 22 and an inward-extending case portion 12. To provide spatial separation within the squib case reliably capable of preventing high-voltage arcs, squibs several inches across would be required, straining both material costs and space requirements.
(While the squib case is commonly described as "floating," this terminology is intended only to mean that the case is floating with respect to the firing circuit. As to RF fields the case readily forms part of an induction loop, and as to electrostatic voltages the case in its operating environment is likely to be securely grounded or effectively at ground, or chassis ground, potential.)
U.S. Pat. No. 3,783,788 offers one ostensible solution to the electrostatic part of this problem--an electrically "leaky" insulator forming the seal between the case interior and ambient. Electrostatic charge accumulating between the pins, or between either pin and the case, dissipates by low-level current flow through the insulator. This may work quite well for reasonably gradual electrostatic accumulation, but it is not likely to offer sufficiently low impedance to prevent RF-induced sparks from terminal to case. Here again as it happens there is a superficial similarity between the internal structure "c" of the referenced patent and a part of the preferred embodiment of the instant invention. However, the structure "c" of the referenced patent is in firm electrical contact with the outer case, and is connected to neither of the two terminals; its function relates to a staging of the ignition of the various explosive charges, rather than to any spark-relief feature.
U.S. Pat. No. 4,061,088 offers another solution to the electrostatic-spark problem: ganged zener diodes between the terminals and between each terminal and the case. These diodes offer operation superior to that in the previous patent discussed, in that deliberately applied ignition signals, being below the zener threshold, are not leaked off and degraded; whereas high-voltage electrostatic charges exceed the zener threshold and are selectively dissipated. This patent represents the most recent in a sequence of progressively more specialized patents to squibs with voltage-discriminating dissipation paths, the first of which issued in 1937 as number U.S. Pat. No. 2,086,548. There are two limitations to the zener-diode approach: first, the behavior of zener diodes in response to RF induced voltages, in the confines of a squib case, is a matter for considerable conjecture or investigation; and, second, the cost of semiconductor devices of this sort may be excessive for many applications. As to the zener RF characteristic, it will be clear that if the zener diode is not fast enough to turn on and conduct sufficient electricity during a given RF half-cycle, that alone would be sufficient to negate the device's beneficial effect. More serious is the question whether the RF field "sees" the zener diode as a conductor at all, and if so whether as a resistive or reactive conductor--and if reactive, to what extent the zener might stand off RF voltage (as suggested in the case of the bridgewire, earlier), permitting a parallel spark. In short, the zener-diode-fitted squib may be totally insensitive to electrostatic interference but still quite sensitive to RF interference.
Another possibility, not described in the referenced patent but explored by the present inventors, is use of a "lossy" RF filter installed in essentially the location of the zener diodes in the previously discussed patent. It has been conclusively demonstrated that such "lossy" RF filters can provide a completely reliable leakage path for all RF induced voltages. However, as with the zener diodes, these filters are expensive; in fact, for one particular design we found that even in extremely large production quantities (e.g., millions, for automotive applications) the filters alone would cost in the neighborhood of $1.50 (1978 value). Thus the filters alone would cost roughly as much as the rest of the squib, doubling the squib cost. Such cost is generally considered unacceptable, outside of the military, spaceflight, or luxury-item fields.
Neither zener-diode and lossy-RF-filter design provides any spark-gap diversion path; both rely instead on the electronic characteristics of the respective components.
U.S. Pat. No. 3,274,937 discloses a spark gap in a two-terminal squib. However, this gap is provided for a different purpose and in a different location and fashion than the gap of the present invention, to be described hereunder. The gap of the referenced patent is in series with the ignition circuit (in this case, a bridgewire), and is intended "to make the detector immune to applied voltages below a certain critical voltage" (emphasis supplied), whereas as will be clear from the description hereunder the gap of the present invention is not in series with the ignition circuit but rather is between that circuit and the squib case, and is designed to make the squib insensitive to voltages above a threshold voltage. As a matter of fact, the referenced patent discloses no particular apparent protection against sparking between the pins and the case, especially as to the nongapped pin.
U.S. Pat. No. 3,257,946 discloses a two-pin, floating-case squib intended to display RF insensitivity, voltage and energy discrimination, and amenability to testing both without and with explosive charge in place, without firing. This device comprises a two-stage charge, with the priming charge separated from a series spark gap by a thin metal membrane. A spark in the gap, if of sufficient intensity, ruptures the membrane, thereby exposing the priming charge to the spark. The spark ignites the priming charge, which in turn ignites the main charge. Though this configuration is described as RF-insensitive, that purported characteristic is said to result from the series spark gap in one terminal pin, and the resulting voltage threshold for firing, coupled with the membrane barrier and its resulting energy threshold for firing. Thus by interference the insensitivity is to interpin RF induction, not pin-to-case induction. Consideration of the geometry suggests that the device may in fact not be at all protected against pin-to-case sparking, particularly via the ungapped pin or the membrane itself.
U.S. Pat. No. 3,971,320 shows a hybrid squib which seems to have coax and dual-pin advantages. It is a coax unit to whose metal case a second pin is electrically connected; the squib is in a plastic outer casing, with a sealed mouth penetrated by terminals. This does not give the coax's relative RF-insensitivity, with the floating case's relative immunity to accidental shorting. Unless the "mounting" which holds the squib, and other items within an inch, are dry, clean nonmetal, the squib is susceptible to arcing--from the inner metal case through plastic to whatever conductor is in striking range. The metal case, connected to one pin, can act just as do the pins in a two-pin floating-case squib, in arcing to the nearest equivalent of the floating case. Of course the reference squib is also as susceptible as any coax squib to interpin RF sparking. The most serious drawback of the reference squib is that the interior and exterior surfaces of the insulating casing 10 cannot be reliably sealed to the inner cup 12 (or the mouth seal) or the aforementioned mounting, respectively. (In many applications the squib itself forms part of a sealed system into which its ignition products are discharged.) This permits two longitudinal leakage paths to arise along the respective annular interfaces, each path passing contaminants inward and hot pyrotechnic gases outward. High-strength seals (welds, solder, compression glass, or threads) function adeuquately only with metal, noninsulating outer cases.
The foregoing discussion generally exhausts the closest related prior art of which we are aware. However, it may be useful also to consider some hypothetical geometries not known or suggested by the prior-art references, but which may be regarded as constructs produced by combining certain features of various references. In particular, single-pin coax squibs could be produced having the spark-gap and membrane of U.S. Pat. No. 3,257,946, but with the return simply connected to the case instead of a second terminal. That is, the metal membrane could be connected to the case. Such a device would of course be susceptible to accidental shorts, as is any coax squib, but it would be susceptible to membrane-to-case sparks, since the membrane would be connected to the case. The remaining question is whether it would be susceptible to sparks between the single terminal and the case. Presumably such sparks would form in the series spark gap provided for ignition sparks. If a parallel, diversion gap were defined in parallel between that terminal and the case, and if the diversion gap operated at a lower voltage than the series gap, then the device would be unfirable. If the diversion gap operated at a higher voltage than the series gap, then the diversion gap would never fire and might as well be omitted. In short, the device hypothesized is not protectable against RF overvoltage across the series spark gap. Concededly such protection might not be required, since RF-induced sparks in that gap would typically be extremely low-current sparks, incapable of rapidly piercing the membrane to gain access to the explosive charge. However, it is possible that if the squib happened to be exposed to RF fields on an essentially continuous basis, as could occur in an automotive environment (to take a circumstance in pertinent point), the low-current sparks could cumulatively degrade the membrane over a period of months or years to the point where the membrane failed. To avoid this result might require making the membrane so thick that it would not rupture rapidly enough, under application of an intentional firing signal, to provide necessary protective time response in a vehicle safety air-bag inflator or the like. In summary, a coax squib with series spark-gap and energy-discriminating membrane would have the usual susceptibility to shorting accidents of all coax squibs, and to avoid cumulative deterioration (and accidental firing) due to RF exposure might well have to have excessively slow response.
Another possibility would be to combine the "leaky" insulator of U.S. Pat. No. 3,783,788 with a coaxial geometry. The referenced patent, as may be recalled, discloses a bridgewire type of ignition means; consequently the hybrid here suggested would have the same possibility, though perhaps remote, of RF sparking in parallel with the bridgewire as any other coax squib with a bridgewire--as previously discussed. The "leaky" insulation would not be any more effective in leaking RF voltage in the coax configuration than in the two-pin configuration. And the device would of course be susceptible to accidental shorting of the single pin to a "hot" circuit element, as also previously described.
One other prior-art feature is worthy of mention, namely the provision of a spark gap between pins and case on the exterior side of a squib seal--that is to say, exposed to ambient. Such a gap is suggested at 32 in FIG. 1. Because such spark gap is so exposed, it is subject to deterioration by mechanical damage, by accumulation of dirt, or by corrosion or oxidation of the surfaces involved. While it may be unlikely that such deterioration could prevent proper bypassing of a high-voltage RF spark, it could result in similar bypassing of a deliberately applied firing signal. Consequently, exposed pin-to-case protective spark gaps are not highly regarded.
When all the constraints discussed in the preceding pages are considered in combination--constraints of response time, cost, size, reliable firing on command, and above all reliable nonfiring in the presence of (1) stray RF fields, (2) electrostatic phenomena and (3) mechanical mishaps--it becomes clear that no prior-art squib adequately satisfies the combined constraints. Just such a combination of constraints characterizes the requirements of the automotive safety devices mentioned earlier.
BRIEF SUMMARY OF THE INVENTION
It is the object of the present invention to satisfy simultaneously all of the constraints of such safety devices, including all of those mentioned in the preceding paragraph.
Our invention accomplishes that object by provision of a spark gap within the same case as the explosive charge and ignition system, in a two-terminal squib with isolated case. As previously mentioned, to provide spatial separations within the squib case reliably capable of preventing high-voltage arcs, squibs several inches across would be required, straining both material costs and space requirements. Consequently, rather than attempting to prevent the sparks they are simply diverted to a safe location within the case.
That is of course not as simple as it sounds. It is necessary to configure the internal structure of the squib carefully to provide a spark gap at a location where there is no significant possibility of explosive-charge ignition. The gap must be at least spatially separated from the explosive charge, and preferably also isolated from the charge by an interposed material barrier. Only by defining a spark gap within the controlled environment of the squib case can reliable spark characteristics be ensured, both as to reliable bypass of spurious voltages and as to reliable nonbypass of deliberately applied firing signals.
In the preferred embodiment of this invention an inner cup is mounted generally coaxially with the squib case, and spot-welded or otherwise securely connected electrically to one of the terminal pins at its interior end. The bottom of the cup is cut away to clear the interior end of the other terminal pin. A bridgewire is connected between the two terminal pins at their interior ends, effectively flush with the bottom of the cup. The top of the cup is flanged outward toward the inner cylindrical surface of the case, forming an annular spark gap; if preferred the flange may be provided with sharp points at cicumferential intervals to concentrate electrical charge and facilitate the forming of a spark. As described in detail hereunder, the cup and flange are stabilized within the case radially and axially by a solid insulating sleeve and washer respectively. The terminal pins are stabilized within the case preferably by embedment in a glass-insulated "header" structure which terminates substantially coplanarly with the interior ends of the terminal pins, so that the bridgewire is supported on the interior surface of the header, and the explosive charge in the region of the cup bottom which is cut away is likewise supported on the header surface. For greatest strength and reliability the header may be welded to the case, to minimize possibility of leakage of moisture, corrosives, or radio-frequency electromagnetic fields.
Additional protection against interterminal sparking may be provided if desired by threading ferrite beads over the two terminal pins, on the external side of the header.
The principles and features introduced above, and their advantages, may be more-fully understood from the detailed disclosure hereunder, with reference to the accompanying drawings, of which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1, already discussed, is a schematic drawing representing the prior art.
FIG. 2 is a similar schematic drawing representing a preferred embodiment of the present invention.
FIG. 3 is a cross-sectional elevation of another embodiment of the present invention.
FIG. 4 is a partially exploded and partially cut away isometric view of the preferred embodiment of FIG. 2.
FIG. 5 is a cross-sectional elevation of the preferred embodiment of FIGS. 2 and 4.
FIG. 6 is a cross-sectional plan view of the same preferred embodiment, taken along the line 6--6 of FIG. 5.
FIG. 7 is a cross-sectional elevation of another embodiment of the invention.
FIG. 8 is a schematic drawing of another embodiment of the invention.
It may be helpful to note that FIGS. 2, 4, 5, 6 and 8 relate to a two-pin, isolated-case squib with a bridgewire used as ignition device.
FIG. 3 relates to a two-pin isolated-case squib with a series spark gap and energy-discriminating membrane used as ignition device.
FIG. 7 relates to a single-pin coax squib with bridgewire.
DESCRIPTION OF PREFERRED EMBODIMENTS
The basic principle of the present invention is shown schematically in FIG. 2. Within isolated case 111, to the prior-art terminals 122 and 123 and bridgewire 121 there is added a conductive shield 112, formed as at 115 to contact one of the terminals, 122, and electrically connected to that terminal 122; the shield furthermore is formed as at 114 to closely approach the interior of case 111 but is spaced (as at 132) therefrom. The shield 112 is also spaced away from the other terminal 123, by being cut away or formed as suggested at 113. Radio-frequency voltages appearing at terminal 122, rather than sparking to case 111 in the vicinity of bridgewire 121, are diverted by shield 112 and particularly its formed section 115 and flanged section 114 to spark gap 132.
Radio-frequency voltages appearing at terminal 123 typically are "leaked off" via bridgewire 121 to terminal 122, and thence via structure 115, 112 and 114 to gap 132 as before. However, as mentioned in the prior-art discussion of this specification, under certain circumstances pin-to-pin RF voltages and sparks may be a problem as well as pin-to-case; if this is considered significant the arrangement of FIG. 8 may be substituted. As suggested in that figure the shield may be split, so that section 412 with flange 414 forming gap 432 with the interior of case 411 is attached at 415 to terminal 422; and separate shield section 412a with flange 414a forming gap 432a with the interior of case 411 is attached at 415a to terminal 423.
In either of these systems it is of course essential to ensure that the explosive charge (not shown in the schematic drawings) is adequately isolated from the spark gap(s). Such isolation is representatively illustrated in the remaining drawings.
The preferred embodiment of FIG. 2 is shown in mechanical detail in FIGS. 4, 5 and 6. The same case 111, shield 112, inward-directed extension 115 and flange 114 of the shield 112, terminals 122 and 123, and spark gap 132 appear in one or more of FIGS. 4, 5 and 6--the spark gap 132 being visible particularly in FIG. 5.
The insulating washer 146 separates the flange 114 from the end wall 116 of the case 111, stabilizing the spark-gap structure axially with respect to the end wall 116. The shield 112 advantageously takes the form of a cup, with bottom 115 partly cut away to clear electrode 123, and with the open end flanged outward at 114 toward the case to form annular gap 132. The explosive charge 147, which in the instance of a squib is formed of pyrotechnic material such as metal and oxidant, rather than primary explosive material, is disposed within and compressed into the cup structure 112. In the case of other electroexplosive initiators such as primers and detonators, more-powerful explosives may be used to form explosive charge 147. The cup 112 is enclosed within insulating sleeve 141 which stabilizes the cup 112, contained charge 147, and spark-gap 132 structure radially with respect to case 111. The insulating sleeve or "charge sleeve" 141 is snap-fitted at 148 to metal header 142, which is mechanically and hermetically sealed by glass seal 143. The seal 143 in turn is penetrated by electrodes 122 and 123. The case 111 is extended longitudinally to permit inclusion within its length of two ferrite beads 144 and 145, respectively designed for function in two overlapping portions of the electromagnetic radiation frequency spectrum. The ferrite beads 144 and 145 function to short-circuit RF fields between the pins 123 and 122, thereby minimizing the likelihood of sparking between those pins. This may be regarded as an alternative to the split-shield arrangement of FIG. 8, for situations in which pin-to-pin discharge is considered a significant problem. In many situations the ferrite beads 144 and 145, as well as the split-shield arrangement, may be considered unnecessary and may be omitted.
The case 111 is crimped inward at 117 (FIG. 5) and welded to the end of the header 142. The length of the inward-extending portion 117 of the case 111 is advantageously greater than the annular radial dimension of the header 142, so that the inward extension 117 covers the interface between the header 142 and ferrite bead 145; there is otherwise some possibility of the header 142 acting as an RF waveguide for transmission of RF fields along that interface and into the region of the explosive charge.
Leadwires 124 and 125 may be soldered or attached by other suitable means to terminals 123 and 122 respectively, thereby incorporating the squib into the firing circuit. In ordinary use of course the case 111 is mounted securely in suitable disposition to a device to be ignited, or to receive the pyrotechnic combustion products for other purposes such as inflation of an automotive air bag.
As to the sequence of construction processes, it will be noted that the interior ends of the terminals 122 and 123 are substantially coplanar with the interior surface of the glass seal 143, facilitating stable positioning of the bridgewire 121 upon that interior surface while spotwelding to the terminals 122 and 123. Following that operation the charge sleeve 141 is snapped into position and the cup 112 inserted into the sleeve 141 and into contact with the said interior surface, and the inward-directed portion 115 of the cup 112 is spotwelded to the terminal 122. Next the explosive charge 147 is volumetrically loaded and tamped into compressed adhesion to the interior of the cup 112. (Excess powder is advantageously removed as by a specialized "vacuum-cleaner" device.) This entire assembly then is inserted into the case 111, preceded only by the insulating washer 146. Ferrite beads 144 and 145 are next threaded over the terminals 123 and 122 and into the shield 142. The end of the case next is crimped inward at 117 and "projection welded" to the shield 142, making use of a sharp annular projection 149 (FIG. 4) initially provided at the open end of the shield 142. After the welding step this projection 149 is substantially flattened out, and so does not appear in FIG. 5. Finally, leadwires or "pigtails" 124 and 125 are added, with transparent plastic protectors 128 permitting visual inspection to monitor quality of the solder joint or other attachment.
As shown in FIG. 3 the present invention may be used in conjunction with the spark-gap ignition system described in the previously discussed U.S. Pat. No. 3,257,946. The reference numerals in FIG. 3 parallel those of FIG. 5, except that the initial number of each is a "3" instead of a "1"; thus, for example, the end of the squib case is designated "316" in FIG. 3 rather than "116" as in FIG. 5. The various correspondingly numbered elements are in fact essentially identical, except as follows. In the system of FIG. 3 there is no bridgewire; instead a metal foil 326 is incorporated as in the referenced patent, and a spark gap 327 is provided between the terminal 323 and the foil 326. Operation is substantially the same as described in the referenced patent, but the spark gap 332 operates analogously to the gap 132 of FIG. 5 to prevent RF-induced sparking between the foil and the case via the explosive charge. For simplicity only one ferrite bead 345 has been shown, rather than two as in FIG. 5. As explained in the referenced patent, the series spark gap 327 sustains an arc only when sufficient voltage is applied across the terminals 322 and 323, thereby screening out or discriminating against spurious voltages which are too low to start an arc in the series gap 327; RF-induced arcing within the gap 327 is characteristically of inadequate current level to rupture the foil 326, but that is not true of the low-impedance source from which deliberately applied firing voltages are obtained, so the foil screens out or discriminates against spurious signals of inadequate energy content. Cumulative deterioration to the foil 326 by long-term exposure to low-power RF sparking is avoided to the extent that the "hot" or "swing" side of the induced RF voltage appears on terminal 322, from which it may be diverted via gap 332 to the case 311. Thus the gap 332 serves a dual function, tending to protect the foil 326 from deterioration by RF exposure and thus avoid long-term damage and eventual unintended firing, as well as protecting the explosive charge against direct ignition by RF voltage, i.e., immediate unintended firing.
As shown in FIG. 7 the present invention may be used in conjunction with a coaxial squib configuration, to overcome the relatively minor danger of RF-induced spark ignition in such devices. Again the reference numerals parallel those used in FIGS. 2 through 6, but in FIG. 7 a numeral "2" is used as the first digit in each rather than a numeral "1" or "3"; and in FIG. 7 there is no separate terminal analogous to 123 in FIG. 5, the bridgewire 221 being, for example, returned via header 242 to the case 211. To the extent that the bridgewire 221 may represent a high impedance to certain RF fields under particular conditions, parallel sparking to the case is prevented by diversion of the RF voltage through cup-shaped shield 212 (including its lower inward-extending section 215 and its upper flange 214) to the case 211 via annular spark gap 232.
In the various embodiments shown the washer 146, 246 or 346 serves as a physical barrier to exposure of the explosive charge to the spark at the annular gap. This physical barrier is desirable primarily in event a few grains of the explosive charge might happen to be loose near the flanged end of the cup; otherwise spatial separation of the spark gap from the main body of the explosive charge would be sufficient to isolate the spark gap from the charge, especially with the inherent spatial separation of the flange geometry. In short, the interposition of an imperforate ignition barrier is not absolutely required, and may be omitted especially in cases where the orientation of the device in use virtually guarantees that there will be no migration of the explosive charge to the region of the spark gap. The relative likelihood of such migration may be best evaluated by a designer skilled in the art of squib design, taking into account the circumstances of a particular application. Thus the provision of "means for isolating the explosive charge from the spark gap," as recited in the appended claims, may in particular appropriate circumstances be accomplished merely by suitable and adequate spatial separation of the charge from the gap.
The spark gap of the various embodiments of the present invention, while particularly directed to avoiding RF-induced sparking through the explosive charge, also serves excellently in avoiding electrostatically caused ignition, without the necessity or uncertainty of "leaky" resistors or expensive semiconductor devices.
Our tests on prototype squibs show that the RF protection afforded by the present invention is not as great as that of "lossy" RF filters, but is completely adequate for many very demanding applications, including the automotive application mentioned earlier, and at a much lower cost. In a typical unit the RF power required for ignition by a pin-to-case spark was below 500 milliwatts without the diverting shield and spark gap, and was well over 10 watts with that structure. Interestingly, even pin-to-pin firing seemed to be favorably affected, and by a factor between 4 and 10.
It will be understood that the foregoing disclosure is exemplary only, and not to be construed as limiting the scope of our invention, which scope is to be ascertained only by reference to the appended claims. | Novel structure within the squib provides an internal spark gap for discharge of radio-frequency as well as static electricity, and isolation of the spark gap from the pyrotechnic charge. The preferred structure is in the form of a cup mounted inside the squib case and containing the pyrotechnic material; the bottom of the cup is partly cut away to permit the igniting filament to contact the pyrotechnic material, while the remainder of the cup bottom is welded to a terminal lead. The top of the cup is flanged outward toward the inside of the case, forming an annular spark gap. This invention is particularly advantageous in a two-pin squib with an electrically floating case, but under certain circumstances is also beneficial in a single-pin or "coaxial" squib. | 5 |
[0001] This is a continuation application of U.S. patent application Ser. No. 08/771,276 filed Dec. 20, 1996, which is a continuation-in-part of U.S. patent application Ser. No. 08/661,393 filed Jun. 7, 1996 (issued as U.S. Pat. No. 6,268,477 on Jul. 31, 2001), which was in turn a continuation-in-part of U.S. patent application No. 08/575,967 filed Dec. 20, 1995 (issued as U.S. Pat. No. 6,265,184 on Jul. 24, 2001). All of these priority applications are incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to signal transduction pathways. More particularly, the present invention relates to chemokine receptors, nucleic acids encoding chemokine receptors, chemokine receptor ligands, modulators of chemokine receptor activity, antibodies recognizing chemokines and chemokine receptors, methods for identifying chemokine receptor ligands and modulators, methods for producing chemokine receptors, and methods for producing antibodies recognizing chemokine receptors.
BACKGROUND OF THE INVENTION
[0003] Recent advances in molecular biology have led to an appreciation of the central role of signal transduction pathways in biological processes. These pathways comprise a central means by which individual cells in a multicellular organism communicate, thereby coordinating biological processes. See Springer, Cell 76:301-314 (1994), Table I, for a model. One branch of signal transduction pathways, defined by the intracellular participation of guanine nucleotide binding proteins (G-proteins), affects a broad range of biological processes.
[0004] Lewin, GENES V 319-348 (1994) generally discusses G-protein signal transduction pathways which involve, at a minimum, the following components: an extracellular signal (e.g., neurotransmitters, peptide hormones, organic molecules, light, or odorants), a signal-recognizing receptor [G-protein-coupled receptor, reviewed in Probst et al., DNA and Cell Biology 11:1-20 (1992) and also known as GPR or GPCR], and an intracellular, heterotrimeric GTP-binding protein, or G protein. In particular, these pathways have attracted interest because of their role in regulating white blood cell or leukocyte trafficking.
[0005] Leukocytes comprise a group of mobile blood cell types including granulocytes (i.e., neutrophils, basophils, and eosinophils), lymphocytes, and monocytes. When mobilized and activated, these cells are primarily involved in the body's defense against foreign matter. This task is complicated by the diversity of normal and pathological processes in which leukocytes participate. For example, leukocytes function in the normal inflammatory response to infection. Leukocytes are also involved in a variety of pathological inflammations. For a summary, see Schall et al., Curr. Opin. Immunol. 6:865-873 (1994). Moreover, each of these processes can involve unique contributions, in degree, kind, and duration, from each of the leukocyte cell types.
[0006] In studying these immune reactions, researchers initially concentrated on the signals acting upon leukocytes, reasoning that a signal would be required to elicit any form of response. Murphy, Ann. Rev. Immunol. 12:593-633 (1994) has reviewed members of an important group of leukocyte signals, the peptide signals. One type of peptide signal comprises the chemokines (chemoattractant cytokines), termed intercrines in Oppenheim et al., Ann. Rev. Immunol. 9:617-648 (1991). In addition to Oppenheim et al., Baggiolini et al., Advances in Immunol. 55:97-179 (1994), documents the growing number of chemokines that have been identified and subjected to genetic and biochemical analyses.
[0007] Comparisons of the amino acid sequences of the known chemokines have led to a classification scheme which divides chemokines into two groups: the a group characterized by a single amino acid separating the first two cysteines (CXC; N-terminus as referent), and the βgroup, where these cysteines are adjacent (CC). See Baggiolini et al., supra. Correlations have been found between the chemokines and the particular leukocyte cell types responding to those signals. Schall et al., supra, has reported that the CXC chemokines generally affect neutrophils; the CC chemokines tend to affect monocytes, lymphocytes, basophils and eosinophils. For example, Baggiolini et al., supra, recited that RANTES, a CC chemokine, functions as a chemoattractant for monocytes, lymphocytes (i.e., memory T cells), basophils, and eosinophils, but not for neutrophils, while inducing the release of histamine from basophils.
[0008] Chemokines were recently shown by Cocchi et. al., Science, 270:1811-1815 (1995) to be suppressors of HIV proliferation. Cocchi et al. (supra) demonstrated that RANTES, MIP-1α, and MIP-1β suppressed HIV-1, HIV-2 and SIV infection of a CD4 + cell line designated PM1 and of primary human peripheral blood mononuclear cells.
[0009] Recently, however, attention has turned to the cellular receptors that bind the chemokines, because the extracellular chemokines seem to contact cells indiscriminately, and therefore lack the specificity needed to regulate the individual leukocyte cell types.
[0010] Murphy (supra) reported that the GPCR superfamily of receptors includes the chemokine receptor family. The typical chemokine receptor structure includes an extracellular chemokine-binding domain located near the N-terminus, followed by seven spaced regions of predominantly hydrophobic amino acids capable of forming membrane-spanning α-helices. Between each of the a-helical domains are hydrophilic domains localized, alternately, in the intra- or extra-cellular spaces. These features impart a serpentine conformation to the membrane-embedded chemokine receptor. The third intracellular loop typically interacts with G-proteins. In addition, Murphy (supra) noted that the intracellular carboxyl terminus is also capable of interacting with G-proteins.
[0011] The first chemokine receptors to be analyzed by molecular cloning techniques were the two neutrophil receptors for human IL8, a CXC chemokine. Holmes et al., Science 253:178-1280 (1991) and Murphy et al., Science 253:1280-1283 (1991), reported the cloning of these two receptors for IL8. Lee et al., J. Biol. Chem. 267:16283-16287 (1992), analyzed the cDNAs encoding these receptors and found 77% amino acid identity between the encoded receptors, with each receptor exhibiting features of the G protein coupled receptor family. One of these receptors is specific for IL-8, while the other binds and signals in response to IL-8, gro/MGSA, and NAP-2. Genetic manipulation of the genes encoding IL-8 receptors has contributed to our understanding of the biological roles occupied by these receptors. For example, Cacalano et al., Science 265:682-684 (1994) reported that deletion of the IL-8 receptor homolog in the mouse resulted in a pleiotropic phenotype involving lymphadenopathy and splenomegaly. In addition, a study of missense mutations described in Leong et al., J. Biol. Chem. 269:19343-19348 (1994) revealed amino acids in the IL-8 receptor that were critical for IL-8 binding. Domain swapping experiments discussed in Murphy (supra) implicated the amino terminal extracellular domain as a determinant of binding specificity.
[0012] Several receptors for CC chemokines have also been identified and cloned. CCCKR1 binds both MIP-1α and RANTES and causes intracellular calcium ion flux in response to both ligands. Charo et al., Proc Natl. Acad. Sci. (USA) 91:2752-2756 (1994) reported that another CC chemokine receptor, MCP-R1 (CCCKR2), is encoded by a single gene that produces two splice variants which differ in their carboxyl terminal domains. This receptor binds and responds to MCP-3 in addition to MCP-1.
[0013] A promiscuous receptor that binds both CXC and CC chemokines has also been identified. This receptor was originally identified on red blood cells and Horuk et al., Science 261:1182-1184 (1993) reports that it binds IL-8, NAP-2, GROα, RANTES, and MCP-1. The erythrocyte chemokine receptor shares about 25% identity with other chemokine receptors and may help to regulate circulating levels of chemokines or aid in the presentation of chemokines to their targets. In addition to binding chemokines, the erythrocyte chemokine receptor has also been shown to be the receptor for plasmodium vivax, a major cause of malaria (id.) Another G-protein coupled receptor which is closely related to chemokine receptors, the platelet activating factor receptor, has also been shown to be the receptor for a human pathogen, the bacterium Streptococcus pneumoniae [Cundell et al., Nature 377:435-438 (1995)].
[0014] In addition to the mammalian chemokine receptors, two viral chemokine receptor homologs have been identified. Ahuja et al., J. Biol. Chem. 268:20691-20694 (1993) describes a gene product from Herpesvirus saimiri that shares about 30% identity with the IL-8 receptors and binds CXC chemokines. Neote et al., Cell, 72:415-425 (1993) reports that human cytomegalovirus contains a gene encoding a receptor sharing about 30% identity with the CC chemokine receptors which binds MIP-1α, MIP-1β, MCP-1, and RANTES. These viral receptors may affect the normal role of chemokines and provide a selective pathological advantage for the virus.
[0015] Because of the broad diversity of chemokines and their activities, there are numerous receptors for the chemokines. The receptors which have been characterized represent only a fraction of the total complement of chemokine receptors. There thus remains a need in the art for the identification of additional chemokine receptors. The availability of these novel receptors will provide tools for the development of therapeutic modulators of chemokine or chemokine receptor function. It is contemplated by the present invention that such modulators are useful as therapeutics for the treatment of atherosclerosis, rheumatoid arthritis, tumor growth suppression, asthma, viral infections, and other inflammatory conditions. Alternatively, fragments or variants of the chemokine receptors, or antibodies recognizing those receptors, are contemplated as therapeutics.
SUMMARY OF THE INVENTION
[0016] The present invention provides purified and isolated nucleic acids encoding chemokine receptors involved in leukocyte trafficking. Polynucleotides of the invention (both sense and anti-sense strands thereof) include genomic DNAs, cDNAs, and RNAs, as well as completely or partially synthetic nucleic acids. Preferred polynucleotides of the invention include the DNA encoding the chemokine receptor 88-2B that is set out in SEQ ID NO:3, the DNA encoding the chemokine receptor 88C that is set out in SEQ ID NO: 1, and DNAs which hybridize to those DNAs under standard stringent hybridization conditions, or which would hybridize but for the redundancy of the genetic code. Exemplary stringent hybridization conditions are as follows: hybridization at 42° C. in 50% formamide, 5X SSC, 20 mM sodium phosphate, pH 6.8 and washing in 0.2X SSC at 55° C.
[0017] It is understood by those of skill in the art that variation in these conditions occurs based on the length and GC nucleotide content of the sequences to be hybridized. Formulas standard in the art are appropriate for determining exact hybridization conditions. See Sambrook et al., §§ 9.47-9.51 in Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y (1989). Also contemplated by the invention are polynucleotides encoding domains of 88-2B or 88C, for example, polynucleotides encoding one or more extracellular domains of either protein or other biologically active fragments thereof. 88-2B extracellular domains correspond to SEQ ID NO:3 and SEQ ID NO:4 at amino acid residues 1-36, 93-107, 171-196, and 263-284. The extracellular domains of 88-2B are encoded by polynucleotide sequences corresponding to SEQ ID NO:3 at nucleotides 362-469, 638-682, 872-949, and 1148-1213. Extracellular domains of 88C correspond to SEQ ID NO: 1 and SEQ ID NO:2 at amino acid residues 1-32, 89-112, 166-191, and 259-280. The 88C extracellular domains are encoded by polynucleotide sequences that correspond to SEQ ID NO: 1 at nucleotides 55-150, 319-390, 550-627, and 829-894. The invention also comprehends polynucleotides encoding intracellular domains of these chemokine receptors. The intracellular domains of 88-2B include amino acids 60-71, 131-151, 219-240, and 306-355 of SEQ ID NO:3 and SEQ ID NO:4. Those domains are encoded by polynucleotide sequences corresponding to SEQ ID NO:3 at nucleotides 539-574, 752-814, 1016-1081, and 1277-1426, respectively. The 88C intracellular domains include amino acid residues 56-67, 125-145, 213-235, and 301-352 of SEQ ID NO: 1 and SEQ ID NO:2. The intracellular domains of 88C are encoded by polynucleotide sequences corresponding to SEQ ID NO: 1 at nucleotides 220-255, 427-489, 691-759, and 955-1110. Peptides corresponding to one or more of the extracellular or intracellular domains, or antibodies raised against those peptides, are contemplated as modulators of receptor activities, especially ligand and G protein binding activities of the receptors.
[0018] The nucleotide sequences of the invention may also be used to design oligonucleotides for use as labeled probes to isolate genomic DNAs encoding 88-2B or 88C under stringent hybridization conditions (i.e., by Southern analyses and polymerase chain reaction methodologies). Moreover, these oligonucleotide probes can be used to detect particular alleles of the genes encoding 88-2B or 88C, facilitating both diagnosis and gene therapy treatments of disease states associated with particular alleles. In addition, these oligonucleotides can be used to alter chemokine receptor genetics to facilitate identification of chemokine receptor modulators. Also, the nucleotide sequences can be used to design antisense genetic elements of use in exploring or altering the genetics and expression of 88-2B or 88C. The invention also comprehends biological replicas (i.e., copies of isolated DNAs made in vivo or in vitro) and RNA transcripts of DNAs of the invention.
[0019] Autonomously replicating recombinant constructions such as plasmid, viral, and chromosomal (e.g., YAC) nucleic acid vectors effectively incorporating 88-2B or 88C polynucleotides, and, particularly, vectors wherein DNA effectively encoding 88-2B or 88C is operatively linked to one or more endogenous or heterologous expression control sequences are also provided.
[0020] The 88-2B and 88C receptors may be produced naturally, recombinantly or synthetically. Host cells (prokaryotic or eukaryotic) transformed or transfected with polynucleotides of the invention by standard methods may be used to express the 88-2B and 88C chemokine receptors. Beyond the intact 88-2B or 88C gene products, biologically active fragments of 88-2B or 88C, analogs of 88-2B or 88C, and synthetic peptides derived from the amino acid sequences of 88-2B, set out in SEQ ID NO:4, or 88C, set out in SEQ ID NO:2, are contemplated by the invention. Moreover, the 88-2B or 88C gene product, or a biologically active fragment of either gene product, when produced in a eukaryotic cell, may be post-translationally modified (e.g., via disulfide bond formation, glycosylation, phosphorylation, myristoylation, palmitoylation, acetylation, etc.) The invention further contemplates the 88-2B and 88C gene products, or biologically active fragments thereof, in monomeric, homomultimeric, or heteromultimeric conformations.
[0021] In particular, one aspect of the invention involves antibody products capable of specifically binding to the 88-2B or 88C chemokine receptors. The antibody products are generated by methods standard in the art using recombinant 88-2B or 88C receptors, synthetic peptides or peptide fragments of 88-2B or 88C receptors, host cells expressing 88-2B or 88C on their surfaces, or 88-2B or 88C receptors purified from natural sources as immunogens. The antibody products may include monoclonal antibodies or polyclonal antibodies of any source or sub-type. Moreover, monomeric, homomultimeric, and heteromultimeric antibodies, and fragments thereof, are contemplated by the invention. Further, the invention comprehends CDR-grafted antibodies, “humanized” antibodies, and other modified antibody products retaining the ability to specifically bind a chemokine receptor.
[0022] The invention also contemplates the use of antibody products for detection of the 88-2B or 88C gene products, their analogs, or biologically active fragments thereof. For example, antibody products may be used in diagnostic procedures designed to reveal correlations between the expression of 88-2B, or 88C, and various normal or pathological states. In addition, antibody products can be used to diagnose tissue-specific variations in expression of 88-2B or 88C, their analogs, or biologically active fragments thereof.
[0023] Antibody products specific for the 88-2B and 88C chemokine receptors may also act as modulators of receptor activities. In another aspect, antibodies to 88-2B or 88C receptors are useful for therapeutic purposes.
[0024] Assays for ligands capable of interacting with the chemokine receptors of the invention are also provided. These assays may involve direct detection of chemokine receptor activity, for example, by monitoring the binding of a labeled ligand to the receptor. In addition, these assays may be used to indirectly assess ligand interaction with the chemokine receptor. As used herein the term “ligand” comprises molecules which are agonists and antagonists of 88-2B or 88C, and other molecules which bind to the receptors.
[0025] Direct detection of ligand binding to a chemokine receptor may be achieved using the following assay. Test compounds (i.e., putative ligands) are detectably labeled (e.g., radioiodinated). The detectably labeled test compounds are then contacted with membrane preparations containing a chemokine receptor of the invention. Preferably, the membranes are prepared from host cells expressing chemokine receptors of the invention from recombinant vectors. Following an incubation period to facilitate contact between the membrane-embedded chemokine receptors and the detectably labeled test compounds, the membrane material is collected on filters using vacuum filtration. The detectable label associated with the filters is then quantitated. For example, radiolabels are quantitated using liquid scintillation spectrophotometry. Using this technique, ligands binding to chemokine receptors are identified. To confirm the identification of a ligand, a detectably labeled test compound is exposed to a membrane preparation displaying a chemokine receptor in the presence of increasing quantities of the test compound in an unlabeled state. A progressive reduction in the level of filter-associated label as one adds increasing quantities of unlabeled test compound confirms the identification of that ligand.
[0026] Agonists are ligands which bind to the receptor and elicit intracellular signal transduction and antagonists are ligands which bind to the receptor but do not elicit intracellular signal transduction. The determination of whether a particular ligand is an agonist or an antagonist can be determined, for example, by assaying G protein-coupled signal transduction pathways. Activation of these pathways can be determined by measuring intracellular ca++ flux, phospholipase C activity or adenylyl cyclase activity, in addition to other assays (see examples 5 and 6).
[0027] As discussed in detail in the Examples herein, chemokines that bind to the 88C receptor include RANTES, MIP-1α, and MIP-1β, and chemokines that bind to the 88-2B receptor include RANTES.
[0028] In another aspect, modulators of the interaction between the 88C and 88-2B receptors and their ligands are specifically contemplated by the invention. Modulators of chemokine receptor function may be identified using assays similar to those used for identifying ligands. The membrane preparation displaying a chemokine receptor is exposed to a constant and known quantity of a detectably labeled functional ligand. In addition, the membrane-bound chemokine receptor is also exposed to an increasing quantity of a test compound suspected of modulating the activity of that chemokine receptor. If the levels of filter-associated label correlate with the quantity of test compound, that compound is a modulator of the activity of the chemokine receptor. If the level of filter-associated label increases with increasing quantities of the test compound, an activator has been identified.
[0029] In contrast, if the level of filter-associated label varies inversely with the quantity of test compound, an inhibitor of chemokine receptor activity has been identified. Testing for modulators of receptor binding in this way allows for the rapid screening of many putative modulators, as pools containing many potential modulators can be tested simultaneously in the same reaction.
[0030] The indirect assays for receptor binding involve measurements of the concentration or level of activity of any of the components found in the relevant signal transduction pathway. Chemokine receptor activation often is associated with an intracellular Ca++ flux. Cells expressing chemokine receptors may be loaded with a calcium-sensitive dye. Upon activation of the expressed receptor, a Ca++ flux would be rendered spectrophotometrically detectable by the dye. Alternatively, the Ca++ flux could be detected microscopically. Parallel assays, using either technique, may be performed in the presence and absence of putative ligands. For example, using the microscopic assay for Ca++ flux, RANTES, a CC chemokine, was identified as a ligand of the 88-2B chemokine receptor. Those skilled in the art will recognize that these assays are also useful for identifying and monitoring the purification of modulators of receptor activity. Receptor activators and inhibitors will activate or inhibit, respectively, the interaction of the receptors with their ligands in these assays.
[0031] Alternatively, the association of chemokine receptors with G proteins affords the opportunity of assessing receptor activity by monitoring G protein activities. A characteristic activity of G proteins, GTP hydrolysis, may be monitored using, for example, 32 P-labeled GTP.
[0032] G proteins also affect a variety of other molecules through their participation in signal transduction pathways. For example, G protein effector molecules include adenylyl cyclase, phospholipase C, ion channels, and phosphodiesterases. Assays focused on any of these effectors may be used to monitor chemokine receptor activity induced by ligand binding in a host cell that is both expressing the chemokine receptor of interest and contacted with an appropriate ligand. For example, one method by which the activity of chemokine receptors may be detected involves measuring phospholipase C activity. In this assay, the production of radiolabeled inositol phosphates by host cells expressing a chemokine receptor in the presence of an agonist is detected. The detection of phospholipase activity may require cotransfection with DNA encoding an exogenous G protein. When cotransfection is required, this assay can be performed by cotransfection of chimeric G protein DNA, for example, Gqi5 [Conklin et al., Nature 363:274-276 (1993)], with 88-2B or 88C DNA and detecting phosphoinositol production when the cotransfected cell is exposed to an agonist of the 88-2B or 88C receptor. Those skilled in the art will recognize that assays focused on G-protein effector molecules are also useful for identifying and monitoring the purification of modulators of receptor activity. Receptor activators and inhibitors will activate or inhibit, respectively, the interaction of the receptors with their ligands in these assays.
[0033] Chemokines have been linked to many inflammatory diseases, such as psoriasis, arthritis, pulmonary fibrosis and atherosclerosis. See Baggiolini et al. (supra).
[0034] Inhibitors of chemokine action may be useful in treating these conditions. In one example, Broaddus et al., J. of Immunol. 152:2960-2967 (1994), describes an antibody to IL-8 which can inhibit neutrophil recruitment in endotoxin-induced pleurisy, a model of acute inflammation in rabbit lung. It is also contemplated that ligand or modulator binding to, or the activation of, the 88C receptor may be useful in treatment of HIV infection and HIV related disease states. Modulators of chemokine binding to specific receptors contemplated by the invention may include antibodies directed toward a chemokine or a receptor, biological or chemical small molecules, or synthetic peptides corresponding to fragments of the chemokine or receptor.
[0035] Administration of compositions containing 88-2B or 88C modulators to mammalian subjects, for the purpose of monitoring or remediating normal or pathological immune reactions And viral infections including infection by retroviruses such as HIV-1, HIV-2 and SIV is contemplated by the invention. In particular, the invention comprehends the mitigation of inflammatory responses, abnormal hematopoietic processes, and viral infections by delivery of a pharmaceutically acceptable quantity of 88-2B or 88C chemokine receptor modulators. The invention further comprehends delivery of these active substances in pharmaceutically acceptable compositions comprising carriers, diluents, or medicaments. The invention also contemplates a variety of administration routes. For example, the active substances may be administered by the following routes: intravenous, subcutaneous, intraperitoneal, intramuscular, oral, anal (i.e., via suppository formulations), or pulmonary (i.e., via inhalers, atomizers, nebulizers, etc.)
[0036] In another aspect, the DNA sequence information provided by the present invention makes possible the development, by homologous recombination or “knockout” strategies [see, e.g. Kapecchi, Science, 244:1288-1292 (1989)], of rodents that fail to express a functional 88C or 88-2B chemokine receptor or that express a variant of the receptor. Alternatively, transgenic mice which express a cloned 88-2B or 88C receptor can be prepared by well known laboratory techniques [Manipulating the Mouse Embryo: A Laboratory Manual, Brigid Hohan, Frank Costantini and Elizabeth Lacy, eds. (1986) Cold Spring Harbor Laboratory ISBN 0-87969-175-I]. Such rodents are useful as models for studying the activities of 88C or 88-2B receptors in vivo.
[0037] Other aspects and advantages of the present invention will become apparent to one skilled in the art upon consideration of the following examples.
DETAILED DESCRIPTION OF THE INVENTION
[0038] The following examples illustrate the invention. Example 1 describes the isolation of genomic DNAs encoding the 88-2B and 88C chemokine receptors. Example 2 presents the isolation and sequencing of cDNAs encoding human 88-2B and 88C and macaque 88C. Example 3 provides a description of Northern analyses revealing the expression patterns of the 88-2B and 88C receptors in a variety of tissues. Example 4 details the recombinant expression of the 88-2B and 88C receptors. Example 5 describes Ca++ flux assays, phosphoinositol hydrolysis assays, and binding assays for 88-2B and 88C receptor activity in response to a variety of potential ligands. Experiments describing the role of 88C and 882B as co-receptors for HIV is presented in Examples 6 and 7. The preparation and characterization of monoclonal and polyclonal antibodies immunoreactive with 88C is described in Example 8. Example 9 describes additional assays designed to identify 88-2B or 88C ligands or modulators.
Example 1
[0039] Partial genomic clones encoding the novel chemokine receptor genes of this invention were isolated by PCR based on conserved sequences found in previously identified genes and based on a clustering of these chemokine receptor genes within the human genome. The genomic DNA was amplified by standard PCR methods using degenerate oligonucleotide primers.
[0040] Templates for PCR amplifications were members of a commercially available source of recombinant human genomic DNA cloned into Yeast Artificial Chromosomes (i.e., YACs) (Research Genetics, Inc., Huntsville, Ala., YAC Library Pools, catalog no. 95011 B). A YAC vector can accommodate inserts of 500-1000 kilobase pairs. Initially, pools of YAC clone DNAs were screened by PCR using primers specific for the gene encoding CCCKR1. In particular, CCCKR(2)-5′, the sense strand primer (corresponding to the sense strand of CCCKR1), is presented in SEQ ID NO: 15. Primer CCCKR(2)-5′ consisted of the sequence 5′-CGTAAGCTTAGAGAAGCCGGGATGGGAA-3′, wherein the underlined nucleotides are the translation start codon for CCCKR1. The anti-sense strand primer was CCCKR-3′ (corresponding to the anti-sense strand of CCCKR1) and its sequence is presented in SEQ ID NO:16. The sequence of CCCKR-3′, 5′-GCCTCTAGAGTCAGAGACCAGCAGA-3′, contains the reverse complement of the CCCKR1 translation stop codon (underlined).
[0041] Pools of YAC clone DNAs yielding detectable PCR products (i.e., DNA bands upon gel electrophoresis) identified appropriate sub-pools of YAC clones, based on a proprietary identification scheme (Research Genetics, Inc., Huntsville, Ala.). PCR reactions were initiated with an incubation at 94° C. for four minutes. Sequence amplifications were achieved using 33 cycles of denaturation at 94° C. for one minute, annealing at 55° C. for one minute, and extension at 72° C. for two minutes.
[0042] The sub-pools of YAC clone DNAs were then subjected to a second round of PCR reactions using the conditions, and primers, that were used in the first round of PCR. Results from sub-pool screenings identified individual clones capable of supporting PCR reactions with the CCCKR-specific primers. One clone, 881F10, contained 640 kb of human genomic DNA from chromosome 3p21 including the genes for CCCKR1 and CCCKR2, as determined by PCR and hybridization. An overlapping YAC clone, 941A7, contained 700 kb of human genomic DNA and also contained the genes for CCCKR1 and CCCKR2. Consequently, further mapping studies were undertaken using these two YAC clones. Southern analyses revealed that CCCKR1 and CCCKR2 were located within approximately 100 kb of one another.
[0043] The close proximity of the CCCKR1 and CCCKR2 genes suggested that novel related genes might be linked to CCCKR1 and CCCKR2. Using DNA from yeast containing YAC clones 881F10 and 941A7 as templates, PCR reactions were performed to amplify any linked receptor genes. Degenerate oligodeoxyribonucleotides were designed as PCR primers. These oligonucleotides corresponded to regions encoding the second intracellular loop and the sixth transmembrane domain of CC chemokine receptors, as deduced from aligned sequence comparisons of CCCKR1, CCCKR2, and V28. V28 was used because it is an orphan receptor that exhibits the characteristics of a chemokine receptor; V28 has also been mapped to human chromosome 3 [Raport et al., Gene 163:295-299 (1995)]. Of further note, the two splice variants of CCCKR2, CCCKR2A and CCCKR2B, are identical in the second intracellular loop and sixth transmembrane domain regions used in the analysis. The 5′ primer, designated V28degf2, contains an internal BamHI site (see below); its sequence is presented in SEQ ID NO:5. The sequence of primer V28degf2 corresponds to DNA encoding the second intracellular loop region of the canonical receptor structure. See Probst et al., supra. The 3′ primer, designated V28degr2, contains an internal HindIII site (see below); its sequence is presented in SEQ ID NO:6. The sequence of primer V28degr2 corresponds to DNA encoding the sixth transmembrane domain of the canonical receptor structure.
[0044] Amplified PCR DNA was subsequently digested with BamHI and HindIII to generate fragments of approximately 390 bp, consistent with the fragment size predicted from inspection of the canonical sequence. Following endonuclease digestion, these PCR fragments were cloned into pBluescript (Stratagene Inc., LaJolla, Calif.). A total of 54 cloned fragments were subjected to automated nucleotide sequence analyses. In addition to sequences from CCCKR1 and CCCKR2, sequences from the two novel chemokine receptor genes of the invention were identified. These two novel chemokine receptor genes were designated 88-2B and 88C.
[0045] Restriction endonuclease mapping and hybridization were utilized to map the relative positions of genes encoding the receptors 88C, 88-2B, CCCKR1, and CCCKR2. These four genes are closely linked, as the gene for 88C is approximately 18 KBP from the CCCKR2 gene on human chromosome 3p21.
EXAMPLE 2
[0046] Full-length 88-2B and 88C cDNAs were isolated from a macrophage cDNA library by the following procedure. Initially, a cDNA library, described in Tjoelker et al., Nature 374:549-553 (1995), was constructed in pRc/CMV (Invitrogen Corp., San Diego, Calif.) from human macrophage MRNA. The cDNA library was screened for the presence of 88-2B and 88C cDNA clones by PCR using unique primer pairs corresponding to 88-2B or 88C. The PCR protocol involved an initial denaturation at 94° C. for four minutes. Polynucleotides were then amplified using 33 cycles of PCR under the following conditions: Denaturation at 94° C. for one minute, annealing at 55° C. for one minute, and extension at 72° C. for two minutes. The first primer specific for 88-2B was primer 88-2B-f1, presented in SEQ ID NO:11. It corresponds to the sense strand of SEQ ID NO:3 at nucleotides 844-863. The second PCR primer specific for the gene encoding 88-2B was primer 88-2B-r1, presented in SEQ ID NO: 12; the 88-2B-r1 sequence corresponds to the anti-sense strand of SEQ ID NO:3 at nucleotides 1023-1042. Similarly, the sequence of the first primer specific for the gene encoding 88C, primer 88C-f1, is presented in SEQ ID NO: 13 and corresponds to the sense strand of SEQ ID NO: 1 at nucleotides 453-471. The second primer specific for the gene encoding 88C is primer 88C-r3, presented in SEQ ID NO: 14; the sequence of 88C-r3 corresponds to the anti-sense strand of SEQ ID NO: 1 at nucleotides 744-763.
[0047] The screening identified clone 777, a cDNA clone of 88-2B. Clone 777 contained a DNA insert of 1915 bp including the full length coding sequence of 88-2B as determined by the following criteria: the clone contained a long open reading frame beginning with an ATG codon, exhibited a Kozak sequence, and had an in-frame stop codon upstream. The DNA and deduced amino acid sequences of the insert of clone 777 are presented in SEQ ID NO:3 and SEQ ID NO:4, respectively. The 88-2B transcript was relatively rare in the macrophage cDNA library. During the library screen, only three 88-2B clones were identified from an estimated total of three million clones.
[0048] Screening for cDNA clones encoding the 88C chemokine receptor identified clones 101 and 134 which appeared to contain the entire 88C coding region, including a putative initiation codon. However, these clones lacked the additional 5′ sequence needed to confirm the identity of the initiation codon. The 88C transcript was relatively abundant in the macrophage cDNA Library. During the library screen, it was estimated that 88C was present at one per 3000 transcripts (in a total of approximately three million clones in the library).
[0049] RACE PCR (Rapid Amplification of cDNA Ends) was performed to extend existing 88C clone sequences, thereby facilitating the accurate characterization of the 5′ end of the 88C cDNA. Human spleen 5′-RACE-ready cDNA was purchased from Clontech Laboratories, Inc., Palo Alto, Calif., and used according to the manufacturer's recommendations. The cDNA had been made “5′ -RACE-ready” by ligating an anchor sequence to the 5′ ends of the cDNA fragments. The anchor sequence is complementary to an anchor primer supplied by Clontech Laboratories, Inc., Palo Alto, Calif. The anchor sequence-anchor primer duplex polynucleotide contains an EcoRI site. Human spleen cDNA was chosen as template DNA because Northern blots had revealed that 88C was expressed in this tissue. The PCR reactions were initiated by denaturing samples at 94° C. for four minutes. Subsequently, sequences were amplified using 35 cycles involving denaturation at 94° C. for one minute, annealing at 60° C. for 45 seconds, and extension at 72° C. for two minutes. The first round of PCR was performed on reaction mixtures containing 2 μl of the 5′-RACE-ready spleen cDNA, 1 μl of the anchor primer, and 1 μl of primer 88c-r4 (100 ng/μl) in a total reaction volume of 50 μl. The 88C-specific primer, primer 88c-r4 (5′-GATAAGCCTCACAGCCCTGTG-3′), is presented in SEQ ID NO:7. The sequence of primer 88c-r4 corresponds to the anti-sense strand of SEQ ID NO: 1 at nucleotides 745-765. A second round of PCR was performed on reaction mixtures including 1 μl of the first PCR reaction with 1 μl of anchor primer and 1 μl of primer 88C-rlb (100 ng/μl) containing the following sequence (5′-GCTAAGCTTGATGACTATCTTTAATGTC-3′) and presented in SEQ ID NO:8. The sequence of primer 88C-rlb contains an internal HindIII cloning site (underlined). The sequence 3′ of the HindIII site corresponds to the anti-sense strand of SEQ ID NO:1 at nucleotides 636-654. The resulting PCR product was digested with EcoRI and HindIII and fractionated on a 1% agarose gel. The approximately 700 bp fragment was isolated and cloned into pBluescript. Clones with the largest inserts were sequenced. Alternatively, the intact PCR product was ligated into vector pCR using a commercial TA cloning kit (Invitrogen Corp., San Diego, Calif.) for subsequent nucleotide sequence determinations.
[0050] The 88-2B and 88C cDNAs were sequenced using the PRISM™ Ready Reaction DyeDeoxy™ Terminator Cycle Sequencing Kit (Perkin Elmer Corp., Foster City, Calif.) and an Applied Biosystems 373A DNA Sequencer. The insert of clone 777 provided the double-stranded template for sequencing reactions used to determine the 88-2B cDNA sequence. The sequence of the entire insert of clone 777 was determined and is presented as the 88-2B cDNA sequence and deduced amino acid sequence in SEQ ID NO:3. The sequence is 1915 bp in length, including 361 bp of 5′ untranslated DNA (corresponding to SEQ ID NO:3 at nucleotides 1-361), a coding region of 1065 bp (corresponding to SEQ ID NO:3 at nucleotides 362-1426), and 489 bp of 3′ untranslated DNA (corresponding to SEQ ID NO:3 at nucleotides 1427-1915). The 88-2B genomic DNA, described in Example 1 above, corresponds to SEQ ID NO:3 at nucleotides 746-1128. The 88C cDNA sequence, and deduced amino acid sequence, is presented in SEQ ID NO: 1. The 88C cDNA sequence is a composite of sequences obtained from RACE-PCR cDNA, clone 134, and clone 101. The RACE-PCR cDNA was used as a sequencing template to determine nucleotides 1-654 in SEQ ID NO: 1, including the unique identification of 9 bp of 5′ untranslated cDNA sequence in SEQ ID NO: 1 at nucleotides 1-9. The sequence obtained from the RACE PCR cDNA confirmed the position of the first methionine codon at nucleotides 55-57 in SEQ ID NO: 1, and supported the conclusion that clone 134 and clone 101 contained full-length copies of the 88C coding region. Clone 134 contained 45 bp of 5′ untranslated cDNA (corresponding to SEQ ID NO: 1 at nucleotides 10-54), the 1056 bp 88C coding region (corresponding to SEQ ID NO:1 at nucleotides 55-1110), and 492 bp of 3′ untranslated cDNA (corresponding to SEQ ID NO:1 at nucleotides 1111-1602). Clone 101 contained 25 bp of 5′ untranslated cDNA (corresponding to SEQ ID NO: 1 at nucleotides 30-54), the 1056 bp 88C coding region (corresponding to SEQ ID NO: 1 at nucleotides 55-1110), and 2273 bp of 3′ untranslated cDNA (corresponding to SEQ ID NO: 1 at nucleotides 1111-3383). The 88C genomic DNA described in Example 1 above, corresponds to SEQ ID NO: 1 at nucleotides 424-809.
[0051] The deduced amino acid sequences of 88-2B and 88C revealed hydrophobicity profiles characteristic of GPCRs, including seven hydrophobic domains corresponding to GPCR transmembrane domains. Sequence comparisons with other GPCRs also revealed a degree of identity. Significantly, the deduced amino acid sequences of both 88-2B and 88C had highest identity with the sequences of the chemokine receptors.
[0052] Table 1 presents the results of these amino acid sequence comparisons.
TABLE 1 Chemokine Receptors 88-2B 88C IL-8RA 30% 30% IL-8RB 31% 30% CCCKR1 62% 54% CCCKR2A 46% 66% CCCKR2B 50% 72% 88-2B 100% 50% 88-C 50% 100%
[0053] Table 1 shows that 88-2B is most similar to CCCKR1 (62% identical at the amino acid level) and 88C is most similar to CCCKR2 (72% identical at the amino acid level).
[0054] The deduced amino acid sequences of 88-2B and 88C also reveal the intracellular and extracellular domains characteristic of GPCRs. The 88-2B extracellular domains correspond to the amino acid sequence provided in SEQ ID NO:3, and SEQ ID NO:4, at amino acid residues 1-36, 93-107, 171-196, and 263-284. The extracellular domains of 88-2B are encoded by polynucleotide sequences corresponding to SEQ ID NO:3 at nucleotides 362-469, 638-682, 872-949, and 1148-1213. Extracellular domains of 88C include amino acid residues 1-32, 89-112, 166-191, and 259-280 in SEQ ID NO: 1 and SEQ ID NO:2. The 88C extracellular domains are encoded by polynucleotide sequences that correspond to SEQ ID NO: 1 at nucleotides 55-150, 319-390, 550-627, and 829-894. The intracellular domains of 88-2B include amino acids 60-71, 131-151, 219-240, and 306-355 of SEQ ID NO:3 and SEQ ID NO:4. Those domains are encoded by polynucleotide sequences corresponding to SEQ ID NO:3 at nucleotides 539-574, 752-814, 1016-1081, and 1277-1426, respectively. The 88C intracellular domains include amino acid residues 56-67, 125-145, 213-235, and 301-352 of SEQ ID NO:1 and SEQ ID NO:2. The intracellular domains of 88C are encoded by polynucleotide sequences corresponding to SEQ ID NO:1 at nucleotides 220-255, 427-489, 691-759, and 955-1110.
[0055] In addition, a macaque 88C DNA was amplified by PCR from macaque genomic DNA using primers corresponding to 5′ and 3′ flanking regions of the human 88C cDNA. The 5′ primer corresponded to the region immediately upstream of and including the initiating Met codon. The 3′ primer was complementary to the region immediately downstream of the termination codon. The primers included restriction sites for cloning into expression vectors. The sequence of the 5′ primer was GAC AAGCTT CACAGGGTGGAACAAGATG (with the HindIII site underlined) (SEQ ID NO: 17) and the sequence of the 3′ primer was GTC TCTAGA CCACTTGAGTCCGTGTCA (with the XbaI site underlined) (SEQ ID NO: 18). The conditions of the PCR amplification were 94° C. for eight minutes, then 40 cycles of 94° C. for one minute, 55° C. for 45 seconds, and 72° C. one minute. The amplified products were cloned into the HindIII and XbaI sites of pcDNA3 and a clone was obtained and sequenced. The full length macaque cDNA and deduced amino acid sequences are presented in SEQ ID NOs:19 and 20, respectively. The nucleotide sequence of macaque 88C is 98% identical to the human 88C sequence. The deduced amino acid sequences are 97% identical.
Example 3
[0056] The mRNA expression patterns of 88-2B and 88C were determined by Northern blot analyses.
[0057] Northern blots containing immobilized poly A++ RNA from a variety of human tissues were purchased from Clontech Laboratories, Inc., Palo Alto, Calif. In particular, the following tissues were examined: heart, brain, placenta, lung, liver, skeletal muscle, kidney, pancreas, spleen, thymus, prostate, testis, ovary, small intestine, colon and peripheral blood leukocytes.
[0058] A probe specific for 88-2B nucleotide sequences was generated from cDNA clone 478. The cDNA insert in clone 478 contains sequence corresponding to SEQ ID NO: 3 at nucleotides 641-1915. To generate a probe, clone 478 was digested and the insert DNA fragment was isolated following gel electrophoresis. The isolated insert fragment was then radiolabeled with 32 P-labeled nucleotides, using techniques known in the art.
[0059] A probe specific for 88C nucleotide sequences was generated by isolating and radiolabeling the insert DNA fragment found in clone 493. The insert fragment from clone 493 contains sequence corresponding to SEQ ID NO: 1 at nucleotides 421-1359. Again, conventional techniques involving 32 P-labeled nucleotides were used to generate the probe.
[0060] Northern blots probed with 88-2B revealed an approximately 1.8 kb mRNA in peripheral blood leukocytes. The 88C Northerns showed an approximately 4 kb MRNA in several human tissues, including a strong signal when probing spleen or thymus tissue and less intense signals when analyzing MRNA from peripheral blood leukocytes and small intestine. A relatively weak signal for 88C was detected in lung tissue and in ovarian tissue.
[0061] The expression of 88C in human T-cells and in hematopoietic cell lines was also determined by Northern blot analysis. Levels of 88C in CD4 + and CD 8 + T-cells were very high. The transcript was present at relatively high levels in myeloid cell lines THP1 and HL-60 and also found in the B cell line Jijoye. In addition, the cDNA was a relatively abundant transcript in a human macrophage cDNA library based on PCR amplification of library subfractions.
Example 4
[0062] The 88-2B and 88C cDNAs were expressed by recombinant methods in mammalian cells.
[0063] For transient transfection experiments, 88C was subcloned into the mammalian cell expression vector pBJ1 [Ishi et al., J. Biol. Chem 270:16435-16440 (1995)]. The construct included sequences encoding a prolactin signal sequence for efficient cell surface expression and a FLAG epitope at the amino terminus of 88C to facilitate detection of the expressed protein. The FLAG epitope consists of the sequence “DYKDDDD. ”COS-7 cells were transiently transfected with the 88C expression plasmid using Lipofectamine (Life Technology, Inc., Grand Island, N.Y.) following the manufacturer's instructions. Briefly, cells were seeded in 24-well plates at a density of 4×10 4 cells per well and grown overnight. The cells were then washed with PBS, and 0.3 mg of DNA mixed with 1.5 μl of lipofectamine in 0.25 ml of Opti-MEM was added to each well. After 5 hours at 37° C., the medium was replaced with medium containing 10% FCS. quantitative ELISA confirmed that 88C was expressed at the cell surface in transiently transfected COS-7 cells using the M1 antibody specific for the FLAG epitope (Eastman Co., New Haven, Conn.).
[0064] The FLAG-tagged 88C receptor was also stably transfected into HEK-293 cells, a human embryonic kidney cell line, using transfection reagent DOTAP (N-[1-[(2,3-Dioleoyloxy)propyl]-N,N,N-trimethyl-ammoniummethylsulfate, Boehringer-Mannheim, Inc., Indianapolis, Ind.) according to the manufacturer's recommendations. Stable lines were selected in the presence of the drug G418. The transfected HEK-293 cells were evaluated for expression of 88C at the cell surface by ELISA, using the Ml antibody to the FLAG epitope. ELISA showed that 88C tagged with the FLAG epitope was expressed at the cell surface of stably transformed HEK-293 Cells.
[0065] The 88-2B and 88C cDNAs were used to make stable HEK-293 transfectants. The 88-2B receptor cDNA was cloned behind the cytomegalovirus promoter in pRc/CMV (Invitrogen Corp., San Diego, Calif.) using a PCR-based strategy. The template for the PCR reaction was the cDNA insert in clone 777. The PCR primers were 88-2B-3 (containing an internal XbaI site) and 88-2B-5 (containing an internal HindIII site).
[0066] The nucleotide sequence of primer 88-2B-3 is presented in SEQ ID NO:9; the nucleotide sequence of primer 88-2B-5 is presented in SEQ ID NO: 10. An 1104 bp region of cDNA was amplified. Following amplification, the DNA was digested with XbaI and HindIII and cloned into similarly digested pRc/CMV. The resulting plasmid was named 777XP2, which contains 18 bp of 5′ untranslated sequence, the entire coding region of 88-2B, and 3 bp of 3′ untranslated sequence. For the 88C sequence, the full-length cDNA insert in clone 134 was not further modified before transfecting HEK-293 cells.
[0067] To create stably transformed cell lines, the pRc/CMV recombinant clones were transfected using transfection reagent DOTAP (N-[1-[(2,3-Dioleoyloxy)propyl]-N,N,N-trimethyl-ammoniummethylsulfate, Boehringer-Mannheim, Inc., Indianapolis, Ind.) according to the manufacturer's recommendations, into HEK-293 cells, a human embryonic kidney cell line. Stable lines were selected in the presence of the drug G418. Standard screening procedures (i.e., Northern blot analyses) were performed to identify stable cell lines expressing the highest levels of 88-2B and 88C mRNA.
EXAMPLE 5
[0068] A. Ca++ Flux Assays
[0069] To analyze polypeptide expression, a functional assay for chemokine receptor activity was employed. A common feature of signaling through the known chemokine receptors is that signal transduction is associated with the release of intracellular calcium cations. Therefore, intracellular Ca++ concentration in the transfected HEK-293 cells was assayed to determine whether the 88-2B or 88C receptors responded to any of the known chemokines.
[0070] HEK-293 cells, stably transfected with 88-2B, 88C (without the FLAG epitope sequence), or a control coding region (encoding IL8R or CCCKR2, see below) as described above, were grown in T75 flasks to approximately 90% confluence in MEM+10% serum. Cells were then washed, harvested with versene (0.6 mM EDTA, 10 mM Na 2 HPO 4 , 0.14 M NaCl, 3 mM KCl, and 1 mM glucose), and incubated in MEM+10% serum+1 μM Fura-2 AM (Molecular Probes, Inc., Eugene, Oreg.) for 30 minutes at room temperature. Fura-2 AM is a Ca++-sensitive dye. The cells were resuspended in Dulbecco's phosphate-buffered saline containing 0.9 mM CaCl 2 and 0.5 mM MgCl 2 (D-PBS) to a concentration of approximately 10 7 cells/ml and changes in fluorescence were monitored using a fluorescence spectrophotometer (Hitachi Model F-4010). Approximately 10 6 cells were suspended in 1.8 ml D-PBS in a cuvette maintained at 37° C. Excitation wavelengths alternated between 340 and 380 nm at 4 second intervals; the emission wavelength was 510 nm. Test compositions were added to the cuvette via an injection port; maximal Ca++ flux was measured upon the addition of ionomycin.
[0071] Positive responses were observed in cells expressing IL-8RA when stimulated with IL-8 and also when CCCKR2 was stimulated with MCP-1 or MCP-3. However, HEK-293 cells expressing either 88-2B or 88C failed to show a flux in intracellular Ca++ concentration when exposed to any of the following chemokines: MCP-1, MCP-2, MCP-3, MIP-1α, MIP-1μ, IL8, NAP-2, gro/MGSA, IP-10, ENA-78, or PF-4. (Peprotech, Inc., Rocky Hill, N.J.).
[0072] Using a more sensitive assay, a Ca++ flux response to RANTES was observed microscopically in Fura-2 AM-loaded cells expressing 88-2B. The assay involved cells and reagents prepared as described above. RANTES (Regulated on Activation, Normal T Expressed and Secreted) is a CC chemokine that has been identified as a chemoattractant and activator of eosinophils. See Neote et al., supra. This chemokine also mediates the release of histamine by basophils and has been shown to function as a chemoattractant for memory T cells in vitro. Modulation of 88-2B receptor activities is therefore contemplated to be useful in modulating leukocyte activation.
[0073] FLAG tagged 88C receptor was expressed in HEK-293 cells and tested for chemokine interactions in the CA++ flux assay. Cell surface expression of 88C was confirmed by ELISA and by FACScan analysis using the M1 antibody. The chemokines RANTES, MIP-1α, and MIP-1β all induced a Ca++ flux in 88C-transfected cells when added at a concentration of 100 nM.
[0074] Ca++ flux assays can also be designed to identify modulators of chemokine receptor binding. The preceding fluorimetric or microscopic assays are carried out in the presence of test compounds. If Ca++ flux is increased in the presence of a test compound, that compound is an activator of chemokine receptor binding. In contrast, a diminished Ca++ flux identifies the test compound as an inhibitor of chemokine receptor binding.
[0075] B. Phosphoinositol Hydrolysis
[0076] Another assay for ligands or modulators involves monitoring phospholipase C activity, as described in Hung et al., J. Biol. Chem. 116:827-832 (1992). Initially, host cells expressing a chemokine receptor are loaded with 3 H-inositol for 24 hours. Test compounds (i.e., potential ligands) are then added to the cells and incubated at 37° C. for 15 minutes. The cells are then exposed to 20 mM formic acid to solubilize and extract hydrolyzed metabolites of phosphoinositol metabolism (i.e., the products of phospholipase C-mediated hydrolysis). The extract is subjected to anion exchange chromatography using an AG1X8 anion exchange column (formate form). Inositol phosphates are eluted with 2 M ammonium formate/0. 1 M formic acid and the 3 H associated with the compounds is determined using liquid scintillation spectrophotometry. The phospholipase C assay can also be exploited to identify modulators of chemokine receptor activity. The aforementioned assay is performed as described, but with the addition of a potential modulator. Elevated levels of detectable label would indicate the modulator is an activator;
[0077] depressed levels of the label would indicate the modulator is an inhibitor of chemokine receptor activity.
[0078] The phospholipase C assay was performed to identify chemokine ligands of the FLAG-tagged 88C receptor. Approximately 24 hours after transfection, COS-7 cells expressing 88C were labeled for 20-24 hours with myo-[2- 3 H]inositol (1 μCi/ml) in inositol-free medium containing 10% dialyzed FCS. Labeled cells were washed with inositol-free DMEM containing 10 mM LiCl and incubated at 37° C. for 1 hour with inositol-free DMEM containing 10 mM LiCl and one of the following chemokines: RANTES, MIP-1β, MIP-1α, MCP-1, IL-8, or the murine MCP-1 homolog JE. Inositol phosphate (IP) formation was assayed as described in the previous paragraph. After incubation with chemokines, the medium was aspirated and cells were lysed by addition of 0.75 ml of ice-cold 20 mM formic acid (30 min). Supernatant fractions were loaded onto AG1-X8 Dowex columns (Biorad, Hercules, Calif.), followed by immediate addition of 3 ml of 50 mM NH 4 OH. The columns were then washed with 4 ml of 40 mM ammonium formate, followed by elution with 2 M ammonium formate. Total inositol phosphates were quantitated by counting beta-emissions.
[0079] Because it has been shown that some chemokine receptors, such as IL8RA AND IL8RB, require contransfection with an exogenous G protein before signaling can be detected in COS-7 cells, the 88C receptor was co-expressed with the chimeric G protein Gqi5 (Conklin, et al., Nature 363:274-276, (1993). Gqi5 ia a G protein which has the carboxyl terminal five amino acids of Gi (which bind to the receptor) spliced onto Gαq. Co-transfection with Gqi5 significantly potentiates signaling by CCCKR1 and CCKR2B. Co-transfection with Gqi5 revealed that 88C signaled well in response to RANTES, MIP-1β, and MIP-1α, but not in response to MCP-1, IL-8 or the murine MCP-1 homologue JE. Dose-response curves revealed EC 50 values of 1 nM for RANTES, 6 nM for MIP-1β, and 22 nM for MIP-1 α.
[0080] 88C is the first cloned human receptor with a signaling response to MIP-1β. Compared with other CC chemokines, MIP-1βclearly has a unique cellular activation pattern. It appears to activate T cells but not monocytes (Baggiolini et al., supra) which is consistent with receptor stimulation studies. For example, while MIP-1βbinds to CCCKR1, it does not induce calcium flux (Neote et al., supra). In contrast, MIP-1α and RANTES bind to and causes signaling in CCCKR1 and CCCKR5 (RANTES also causes activation of CCCKR3). MIP-1p thus appears to be much more selective than other chemokines of the CC chemokine family. Such selectivity is of therapeutic significance because a specific beneficial activity can be stimulated (such as suppression of HIV infection) without stimulating multiple leukocyte populations which results in general pro-inflammatory activities.
[0081] C. Binding Assays
[0082] Another assay for receptor interaction with chemokines was a modification of the binding assay described by Ernst et al., J. Immunol. 152:3541-3549 (1994). MIP-1β as labeled using the Bolton and Hunter reagent (di-iodide, NEN, Wilmington, Del.), according to the manufacturer's instructions. Unconjugated iodide was separated from labeled protein by elution using a PD-10 column (Pharmacia) equilibrated with PBS and BSA (1% w/v). The specific activity was typically 2200 Ci/mmole. Equilibrium binding was performed by adding 125 I-labeled ligand with or without a 100-fold excess of unlabeled ligand, to 5×10 5 HEK-293 cells transfected with 88C tagged with the FLAG epitope in polypropylene tubes in a total volume of 300 μl(50 mM HEPES pH 7.4, 1 mM CaCl 2 , MgCl 2 , 0.5% BSA) and incubating for 90 minutes at 27° C. with shaking at 150 rpm. The cells were collected, using a Skatron cell harvester (Skatron Instruments Inc., Sterling, Va.), on glass fiber filters presoaked in 0.3% polyethyleneimine and 0.2% BSA. After washing, the filters were removed and bound ligand was quantitated by counting gamma emissions. Ligand binding by competition with unlabeled ligand was determined by incubation of 5×10 5 transfected cells (as above) with 1.5 nM of radiolabeled ligand and the indicated concentrations of unlabeled ligand. The samples were collected, washed and counted as above. The data was analyzed using the curve-fitting program Prism (GraphPad Inc., San Diego, Calif.) and the iterative non-linear regression program, LIGAND (PM220).
[0083] In equilibrium binding assays, 88C receptor bound radiolabeled MIP-1β in a specific and saturable manner. Analysis of this binding data by the method of Scatchard revealed a dissociation constant (Kd) of 1.6 nM. Competition binding assays using labeled MIP-1β revealed high-affmity binding of MIP-1β(IC 50 =7.4 nM), RANTES (IC 50 =6.9 nM), and MIP-1α(IC 50=7.4 nM), consistent with the signaling data obtained in transiently transfected COS-7 cells as discussed in section B above.
[0084] Example 6
[0085] The chemokines MIP-1α, MIP-1β and RANTES have been shown to inhibit replication of HIV-1 and HIV-2 in human peripheral blood mononuclear cells and PM1 cells (Cocchi et al., supra). In view of this finding and in view of the results described in Example 5, the present invention contemplates that activation of or ligand binding to the 88C receptor may provide a protective role in HIV infection.
[0086] Recently, it has been reported that the orphan G protein-coupled receptor, fusin, can act as a co-receptor for HIV entry. Fusin/CXCR4 in combination with CD4, the primary HIV receptor, apparently facilitates HIV infection of cultured T cells ([Feng et al., Science 272:872-877 (1996)]. Based upon the homology of fusin to chemokine receptors and the chemokine binding profile of 88C, and because 88C is constitutively expressed in T cells and abundantly expressed in macrophages, 88C is likely to be involved in viral and HIV infection.
[0087] The function of 88C and 88-2B as co-receptors for HIV was determined by transfecting cells which express CD4 with 88C or 88-2B and challenging the co-transfected cells with HIV. Only cells expressing both CD4 and a functional co-receptor for HIV become infected. HIV infection can be determined by several methods. ELISAs which test for expression of HIV antigens are commercially available, for example Coulter HIV-1 p 24 antigen assay (U.S. Pat. No. 4,886,742), Coulter Corp., 11800 SW 147th Ave., Miami, Fla. 33196. Alternatively, the test cells can be engineered to express a reporter gene such as LACZ attached to the HIV LTR promoter [Kimpton et al., J. Virol. 66:2232-2239 (1992)]. In this method, cells that are infected with HIV are detected by a colorimetric assay.
[0088] 88C was transiently transfected into a cat cell line, CCC [Clapham, et al., 181:703-715 (1991)], which had been stably tranformed to express human CD4 (CCC-CD4). These cells are normally resistant to infection by any strain of HIV-1 because they do not endogenously express 88C. In these experiments, CCC/CD4 cells were transiently transfected with 88C cloned into the expression vector pcDNA3.1 (Invitrogen Corp., San Diego, Calif.) using lipofectamine (Gibco BRL, Gaithersburg, Md.). Two days after transfection, cells were challenged with HIV. After 4 days of incubation, cells were fixed and stained for p24 antigen as a measure of HIV infection. 88C expression by these cells rendered them susceptible to infection by several strains of HIV-1. These strains included four primary non-syncytium-inducing HIV-1 isolates (M23, E80, SL-2 and SF-162) which were shown to use only 88C as a co-receptor but not fusin. Several primary syncytium-inducing strains of HIV-1 (2006, M13, 2028 and 2076) used either 88C or fusin as a co-receptor. Also, two established clonal HIV-1 viruses (GUN-1 and 89.6) used either 88C or fusin as a co-receptor.
[0089] It has been reported that some strains of HIV-2 can infect certain CD4-negative cell lines, thus implying a direct interaction of HIV-2 with a receptor other than CD4 [Clapham et al., J. Virol. 66:3531-3537 (1992)] For some strains of HIV-2, this infection is facilitated by the presence of soluble CD4 (sCD4). Since 88-2B shares high sequence similarity with other chemokine receptors that act as HIV co-receptors (namely 88C and fusin), 88-2B was considered to be a likely HIV-2 co-receptor. The role of 88-2B as an HIV-2 co-receptor was demonstrated using HIV-2 strain ROD/B. Cat CCC cells which do not endogenously express CD4 were transfected with 88-2B. In these experiments, cells were transfected with pcDNA3.1 containing 88-2B using lipofectamine and infected with HIV-2 48 hours later. Three days after infection, cells were immunostained for the presence of HIV-2 envelope glycoproteins. The presence of sCD4 during HIV-2 ROD/B challenge increased the infection of these cells by 10-fold. The entry of HIV-2 into the 88-2B transfected cells could be blocked by the presence of 400-800 ng/ml eotaxin, one of the ligands for 88-2B. The baseline infectivity levels of CCC/88-2B (with no soluble CD4) were equivalent to CCC cells which were not transfected with 88-2B.
[0090] The role of 88-2B and 88C as co-receptors for HIV was confirmed by preparing and challenging cell lines stably transformed to express 88C or 88-2B with various strains of HIV and SIV. These results are described in Example 7.
[0091] Alternatively, the co-receptor role of 88C and 88-2B can be demonstrated by an experimental method which does not require the use of live virus. In this method, cell lines co-expressing 88C or 88-2B, CD4 and a LACZ reporter gene are mixed with a cell line co-expressing the HIV envelope glycoprotein (ENV) and a transcription factor for the reporter gene construct [Nussbaum et al., J. Virol. 68:5411 (1994)]. Cells expressing a functional co-receptor for HIV will fuse with the ENV expressing cells and thereby allow expression of the reporter gene. In this method, detection of reporter gene product by colorimetric assay indicates that 88C or 88-2B function as a co-receptor for HIV.
[0092] The mechanism by which chemokines inhibit viral infection has not yet been elucidated. One possible mechanism involves activation of the receptor by binding of a chemokine. The binding of the chemokine leads to signal transduction events in the cell that renders the cell resistant to viral infection and/or prevents replication of the virus in the cell. Similar to interferon induction, the cell may differentiate such that it is resistant to viral infection, or an antiviral state is established. Alternatively, a second mechanism involves direct interference with viral entry into cells by blocking access of viral envelope glycoproteins to the co-receptor by chemokine binding. In this mechanism, G-protein signaling is not required for chemokine suppression of HIV infection.
[0093] To distinguish between two mechanisms by which 88C or 88-2B may function as co-receptors for viral or HIV infection, chemokine binding to the receptor is uncoupled from signal transduction and the effect of the chemokine on suppression of viral infection is determined.
[0094] Ligand binding can be uncoupled from signal transduction by the addition of compounds which inhibit G-protein mediated signaling. These compounds include, for example, pertussis toxin and cholera toxin. In addition, downstream effector polypeptides can be inhibited by other compounds such as wortmannin. If G-protein signaling is involved in suppression of viral infection, the addition of such compounds would prevent suppression of viral infection by the chemokine. Alternatively, key residues or receptor domains of 88C or 88-2B receptor required for G-protein coupling can be altered or deleted such that G-protein coupling is altered or destroyed but chemokine binding is not affected.
[0095] Under these conditions, if chemokines are unable to suppress viral or HIV infection, then signaling through a G-protein is required for suppression of viral or HIV infection. If however, chemokines are able to suppress viral infection, then G-protein signaling is not required for chemokine suppression of viral infection and the protective effects of chemokines may be due to the chemokine blocking the availability of the receptor for the virus.
[0096] Another approach involves the use of antibodies directed against 88C or 88-2B. Antibodies which bind to 88C or 88-2B which can be shown not to elicit G-protein signaling may block access to the chemokine or viral binding site of the receptor. If in the presence of antibodies to 88C or 88-2B, viral infection is suppressed, then the mechanism of the protective effects of chemokines is blocking viral access to its receptor. Feng et al. (1996) reported that antibodies to the amino terminus of the fusin receptor suppressed HIV infection.
[0097] Example 7
[0098] Cell lines were stably transformed with 88C or 88-2B to further delineate the role of 88C and 88-2B in HIV infection. Kimpton and Emerman [“Detection of Replication-Competent and Pseudotyped Human Immunodeficiency Virus with a Sensitive Cell Line on the Basis of Activation of an Integrated Beta-Galactosidase Gene,” J. Virol, 66(4):2232-2239 (1992)] previously described an indicator cell line, herein identified as HeLa-MAGI cells. HeLa-MAGI cells are HeLa cells that have been stably transformed to express CD4 as well as integrated HIV-1 LTR which drives expression of a nuclear localized β-galactosidase gene. Integration of an HIV provirus in the cells leads to production of the viral transactivator, Tat, which then turns on expression of the β-galactosidase gene. The number of cells that stain positive with X-gal for β-galactosidase activity in situ is directly proportional to the number of infected cells.
[0099] These HeLa-MAGI cells can detect lab-adapted isolates of HIV-1 but only a minority of primary isolates [Kimpton and Emerman, supra], and cannot detect most SIV isolates [Chackerian et al., “Characterization of a CD4-Expressing Macaque Cell Line that can Detect Virus After A Single Replication Cycle and can be infected by Diverse Simian Immunodeficiency Virus Isolates,” Virology, 213(2):6499-6505 (1995)].
[0100] In addition, Harrington and Geballe [“Co-Factor Requirement for Human Immunodeficiency Virus Type 1 Entry into a CD4-Expressing Human Cell Line, J. Virol., 67:5939-5947 (1993)] described a cell line based on U373 cells that had been engineered to express CD4 and the same LTR-β-galactosidase construct. It was previously shown that this cell line, herein identified as U373-MAGI, could not be infected with any HIV (M or T-tropic) strain of HIV, but could be rendered susceptible to infection by fusion with HeLa cells (Harrington and Geballe, supra).
[0101] In order to construct indicator cell lines that could detect either macrophage or T cell tropic viruses, epitope-tagged 88C or 88-2B encoding DNA was transfected into HeLa-MAGI or U373-MAGI cells by infection with a retroviral vector to generate HeLa-MAGI-88C or U373-MAGI-88C cell lines, respectively. Expression of the co-receptors on the cell surface was demonstrated by immunostaining live cells using the anti-FLAG M1 antibody and by RT-PCR.
[0102] The 88C and 88-2B genes utilized to construct HeLa-MAGI-88C and U373-MAGI-88C included sequences encoding the prolactin signal peptide followed by a FLAG epitope as described in Example 4. This gene was inserted into the retroviral vector pBabe-Puro [Morgenstern and Land, Nucleic Acids Research, 18(12):3587-3596 (1990)].
[0103] High titer retroviral vector stocks pseudotyped with the VSV-G protein were made by transient transfection as described in Bartx et al., J. Virol. 70:2324-2331 (1996), and used to infect HeLa-MAGI and U373-MAGI cells. Cells resistant to 0.6 μ/ml puromycin (HeLa) or 1 μ/ml puromycin (U373) were pooled. Each pool contained at least 1000 independent transduction events. An early passage (passage 2) stock of the original HeLa-MAGI cells (Kimpton and Emerman, supra) was used to create HeLa-MAGI-88C cells.
[0104] Infections of the indicator cell lines with HIV were performed in 12-well plates with 10-fold serial dilutions of 300 μl of virus in the presence of 30 μ/ml DEAE-Dextran as described (Kimpton and Emerman, supra).
[0105] All HIV-1 strains and SIV mac 239 were all obtained from the NIH AIDS Reference and Reagent Program. Molecular clones of primary HIV-2 7312A [Gao et al., “Genetic Diversity of Human Immunodeficiency Virus Type 2: Evidence for Distinct Sequence Subtypes with Differences in Virus Biology,” J. Virol., 68(11):7433-7447 (1992)] and SIVsmPbj1.9 [Dewhurst et al., “Sequence Analysis and Acute Pathogenicity of Molecularly Cloned SIV smm -PBj14,” Nature, 345:636-640 (1990)] were obtained from B.
[0106] Hahn (UAB). All other SIV mne isolates were obtained from Julie Overbaugh (U.
[0107] Washington, Seattle). Stocks from cloned proviruses were made by transient transfection of 293 cells. Other viral stocks were made by passage of virus in human peripheral blood mononuclear cells or in CEMx174 cells (for SIV stocks.) Viral stocks were normalized by ELISA or p24 gag (Coulter Immunology) or p27 gag (Coulter Immunology) for HIV-1 and HIV-2/SIV, respectively, using standards provided by the manufacturer.
[0108] U373-MAGI-88C cells and U373-MAGI cells (controls) and were infected with limiting dilutions of a T-tropic strain of HIV-1 (HIV LAI ), an M-tropic strain (HIV YU-2 ), and an SIV isolate, SIV MAC 239.Infectivity was measured by counting the number of blue cells per well per volume of virus (Table 2).
TABLE 2 titer on cell line (IU/ml) b virus strain a U373-MAGI U373-MAGI-88C HIV-1 LAI <100 <100 HIV-1 YU-2 <100 2.2 × 10 6 SIV MAC 239 1.2 × 10 3 4 × 10 5
[0109] Two days after infection, cells were fixed and stained for β-galactosidase activity with X-gal. The U373-derived MAGI cells were stained for 120 minutes at 370° C. and the HeLa-derived MAGI cells were stained for 50 minutes at 37° C. Background staining of non-infected cells never exceeded more than approximately three blue cells per well. Only dark blue cells were counted, and syncytium with multiple nuclei were counted as a single infected cell. The infectious titer is the number of blue cells per well multiplied by the dilution of virus and normalized to 1 ml. The titer of HIV YU-2 on U373-MAGI-88C cells was 2×10 6. In contrast, the titer of HIV-1 LA1 , was less than 100 on U373-MAGI-88C. Thus, the specificity of a particular HIV strain for 88C varied by four orders of magnitude.
[0110] Although SIV MAC 239 infection was increased to 4×10 5 in U373-MAGI-88C it also clearly infected U373-MAGI cells (Table 2).
[0111] Next, a series of primary uncloned HIV strains and cloned M-tropic strains of HIV-1 were analyzed for their ability to infect indicator cell lines that express 88C.
[0112] As described above, HeLa-MAGI and HeLa-MAGI-88C cells were infected with limiting dilutions of various HIV strains. The two cloned M-tropic viruses, HIV JR-CSF and HIV YU-2 , both infected HeLa-MAGI-88C, but not HeLa-MAGI cells, showing that both strains use 88C as a co-receptor (Table 3, See note c). However, a great disparity in the ability of each of these two viral strains to infect HeLa-MAGI-88C cells was observed, 6.2×10 5 IU/ml for HIV YU-2 and 1.2×10 4 for HIV JR-CSF . The infectivity of virus stock (Table 3) is the number of infectious units per physical particle (represented here by the amount of viral core protein). In addition, it was observed that the infectivity of these two cloned viral strains differed by over 50-fold in viral stocks that were independently prepared.
[0113] The variability of infectivity of primary viral isolates was further examined by analyzing a collection of twelve different uncloned virus stocks from three different clades (Table 3). Three clade A primary isolates, three clade E isolates, and three additional clade B isolates from geographically diverse origins were used. With all nine strains, the primary strains of HIV could be detected on HeLa-MAGI-88C cells, but not on HeLa-MAGI cells (Table 3). However, the efficacy of infection varied from five infectious units per ng p24 gag to over 100 infectious units per ng p24 gag (table 3). These results indicate that absolute infectivity of M-tropic strains varies considerably and is independent of clade. A hypothesis that may explain this discrepancy may involve the affinity of the V3 loop of each viral strain for 88C after CD4 binding [Trkola et al., Nature, 384(6605):184-187 (1996); Wu et al., Nature, 384(6605):179-183 (1996)].
[0114] Table 3
TABLE 3 viral sub-type titer (IU/ml) (country of on HeLa- P24 gag virus strain a origin) b MAGI-88C c ng/ml Infectivity d HIV-1 YU-2 B (USA) 6.2 × 10 5 2200 281 HIV-1 JR-CSF B (USA) 12000 2800 4.2 HIV-1 TH020 E (Thailand) 4133 93 44 HIV-1 TH021 E (Thailand) 4967 52 96 HIV-1 TH022 E (Thailand) 200 15 13 HIV-1 US660 B (USA) 2367 127 19 HIV-1 UG031 A (Uganda) 1633 71 23 HIV-1 RW009 A (Rwanda) 3333 158 21 HIV-1 RW026 A (Rwanda) 739 143 5.2 HIV-1 US727 B (USA) 14,067 289 49 HIV-1 US056 B (USA) 5833 284 21 HIV-1 LAI B (France) 2.8 × 10 5 167 1600
[0115] The ability of the HeLa-MAGI-88C cells to detect HIV-2 and other SIV strains was also determined. HIV-2 Rod has been reported to use fusin as a receptor even in the absence of CD4 [Endres et al., Cell, 87(4):745-756 (1996)]. HIV-2 Rod is able to infect HeLa-MAGI cells, however its infectivity is enhanced at least 10-fold in HeLa-MagI-88C (Table 4). HeLa cells endogenously express fusin. Thus, the molecular clone of HIV-2 Rod is dual tropic, and is able to use 88C as one of its co-receptors in addition to CXCR4. Similarly, a primary strain of HIV-2 7312A infected HeLa-MAGI-88C cells and not the HeLa-MAGI cells, indicating that like primary strain of HIV-1, it uses 88C as a receptor.
TABLE 4 titer (IU/ml) titer (IU/ml) Infectivity on HeLa- on HeLa- on HeLa- virus strain a reference MAGI b MAGI-88C MAGI-88C c HIV-2 ROD9 (Guyader et al., 967 5900 13 1987) HIV-2 7312A (Gao et al., <30 6500 17 1994) SIV MAC 239 (Naidu et al., <30 20900 90 1988) SIV MNE c18 (Overbaugh et <30 15700 19 al., 1991) SIV MNE 170 (Rudensey et <30 10700 27 al., 1995) SIV SM Pbj1.9 (Dewhurst et <30 776 ND d al., 1990) SIV AGM 9063 (Hirsch et al., <30 50 <1 1995)
[0116] None of the SIV strains tested infected the HeLa-MAGI cells (Table 4), and none infected HeLa-MAGI cells that expresses 88-2B. This indicates that an alternative co-receptor used by SIV in U373 cells is not expressed in HeLa cells, and is not 88-2B. All SIV strains tested infected the HeLa-MAGI-88C cells to some extent (Table 3) indicating that all of the tested SIV strains use at least 88C as one of their co-receptors.
[0117] The classification of M-tropic and T-tropic strains of HIV in the past has often been correlated with another designation “non-syncytium inducing” (NSI), and “syncytium inducing” (SI), respectively. Assays based on the cell lines described herein are sensitive to syncytium formation. The infected cells can form large and small foci of infection containing multiple nuclei (Kimpton and Emerman, supra).
[0118] Experiments using multiple different viral strains and U373-MAGI-88C or HeLa-MAGI-88C indicate that SI/NSI designation is not meaningful because all viral strains formed syncytia if the correct co-receptor was present. These experiments show that syncytium formation is more likely a marker for the presence of an appropriate co-receptor on the infected cell, rather than an indication of tropism. Infection of the HeLa-MAGI-88C cells with SIV strains reported in the literature to be non-syncytium forming strains, in particular, SIV MAC 239, SIV MNE c18, and SIV MNE 170, was remarkable because the size of the syncytia induced in the monolayer was much larger than those induced by any other the HIV strains.
[0119] EXAMPLE 8
[0120] Mouse monoclonal antibodies which specifically recognize 88C were prepared. The antibodies were produced by immunizing mice with a peptide corresponding to the amino terminal twenty amino acids of 88C. The peptide was conjugated to Keyhole Limpet Cyanin (KLH) according to the manufacturer's directions (Pierce, Imject maleimide activated KLH), emulsified in complete Freund's adjuvant and injected into five mice. Two additional injections of conjugated peptide in incomplete Freund's adjuvant occurred at three week intervals. Ten days after the final injection, serum from each of the five mice was tested for immunoreactivity with the twenty amino acid peptide by ELISA. In addition, the immunoreactivity of the sera were tested against intact 88C receptor expressed on the surface of 293 cells by fluorescence activated cell sorting (FACS). The mouse with the best anti-88C activity was chosen for spleen cell fusion and production of monoclonal antibodies by standard laboratory methods. Five monoclonal cell lines (227K, 227M, 227N, 227P, and 227R) were established which produced antibodies that recognized the peptide by ELISA and the 88C protein on 293 cells by FACS. Each antibody was shown to react only with 88C-expressing 293 cells, but not with 293 cells expressing the closely related MCP receptor (CCCKR-2). Each antibody was also shown to recognize 88C expressed transiently in COS cells.
[0121] Rabbit polyclonal antibodies were also generated against 88C. Two rabbits were injected with conjugated amino-terminal peptide as described above. The rabbits were further immunized by four additional injections of the conjugated amino-terminal peptide. Serum from each of the rabbits (2337J and 2470J) was tested by FACS of 293 cells expressing 88C. The sera specifically recognized 88C on the surface of 293 cells.
[0122] The five anti-88C monoclonal antibodies were tested for their ability to block infection of cells by SIV, the simian immunodeficiency virus closely related to HIV [Lehner et al., Nature Medicine, 2:767 (1996)]. Simian CD4 + T cells, which are normally susceptible to infection by SIV, were incubated with the SIV mac 32HJ5 clone in the presence of the anti-88C monoclonal antibody supernatants diluted 1:5. SIV infection was measured by determining reverse transcriptase (RT) activity on day nine using the RT detection and quantification method (Quan-T-RT assay kit, Amersham, Arlington Heights, Ill.). Four of the antibodies were able to block SIV infection: antibody 227K blocked by 53%, 227M by 59%, 227N by 47% and 227P by 81%. Antibody 227R did not block SIV infection.
[0123] The five monoclonal antibodies raised against human 88C amino-terminal peptide were also tested for reactivity against macaque 88C (SEQ ID NO: 20) (which has two amino acid differences from human 88C within the amino-terminal peptide region).
[0124] The coding regions of human 88C and macaque 88C were cloned into the expression vector pcDNA3 (Invitrogen). These expression plasmids were used to transfect COS cells using DEAE. The empty vector was used as a negative control. Three days after transfection, cells were harvested and incubated with the five anti-88C monoclonal antibodies and prepared for FACS. The results showed that four of the five antibodies (227K, 227M, 227N, and 227P) recognized macaque 88C while one (227R) did not. All five antibodies recognized the transfected human 88C, and none cross-reacted with cells transfected with vector alone. On Feb. 4, 1997, the Applicants deposited hybridoma cell lines 227P, 227R, and 227M with the American Type Culture Collection (ATCC), which is located at 10801 University Blvd., Manassas, Va. 20110-2209, USA, pursuant to the provisions of the Budapest Treaty. These hybridoma cell lines were accorded ATCC designations HB-12281, HB-12282, and HB-12283, respectively.
EXAMPLE 9
[0125] Additional methods may be used to identify ligands and modulators of the chemokine receptors of the invention.
[0126] In one embodiment, the invention comprehends a direct assay for ligands.
[0127] Detectably labeled test compounds are exposed to membrane preparations presenting chemokine receptors in a functional conformation. For example, HEK-293 cells, or tissue culture cells, are transfected with an expression vehicle encoding a chemokine receptor. A membrane preparation is then made from the transfected cells expressing the chemokine receptor. The membrane preparation is exposed to 125 I-labeled test compounds (e.g., chemokines) and incubated under suitable conditions (e.g., 10 minutes at 37° C.). The membranes, with any bound test compounds, are then collected on a filter by vacuum filtration and washed to remove unbound test compounds. The radioactivity associated with the bound test compound is then quantitated by subjecting the filters to liquid scintillation spectrophotometry. The specificity of test compound binding may be confirmed by repeating the assay in the presence of increasing quantities of unlabeled test compound and noting the level of competition for binding to the receptor. These binding assays can also identify modulators of chemokine receptor binding. The previously described binding assay may be performed with the following modifications. In addition to detectably labeled test compound, a potential modulator is exposed to the membrane preparation. An increased level of membrane-associated label indicates the potential modulator is an activator; a decreased level of membrane-associated label indicates the potential modulator is an inhibitor of chemokine receptor binding.
[0128] In another embodiment, the invention comprehends indirect assays for identifying receptor ligands that exploit the coupling of chemokine receptors to G proteins. As reviewed in Linder et al., Sci. Am., 267:56-65 (1992), during signal transduction, an activated receptor interacts with a G protein, in turn activating the G protein. The G protein is activated by exchanging GDP for GTP. Subsequent hydrolysis of the G protein-bound GTP deactivates the G protein. One assay for G protein activity therefore monitors the release of 32 p i from [γ- 32 P]-GTP. For example, approximately 5×10 7 HEK-293 cells harboring plasmids of the invention are grown in MEM+10% FCS. The growth medium is supplemented with 5 mCi/ml [ 32 P]-sodium phosphate for 2 hours to uniformly label nucleotide pools. The cells are subsequently washed in a low-phosphate isotonic buffer. One aliquot of washed cells is then exposed to a test compound while a second aliquot of cells is treated similarly, but without exposure to the test compound. Following an incubation period (e.g., 10 minutes), cells are pelleted, lysed and nucleotide compounds fractionated using thin layer chromatography developed with 1 M LiCl. Labeled GTP and GDP are identified by co-developing known standards. The labeled GTP and GDP are then quantitated by autoradiographic techniques that are standard in the art. Relatively high levels of 32 P-labeled GDP identify test compounds as ligands. This type of GTP hydrolysis assay is also useful for the identification of modulators of chemokine receptor binding.
[0129] The aforementioned assay is performed in the presence of a potential modulator. An intensified signal resulting from a relative increase in GTP hydrolysis, producing 32P-labeled GDP, indicates a relative increase in receptor activity. The intensified signal therefore identifies the potential modulator as an activator. Conversely, a diminished relative signal for 32 P-labeled GDP, indicative of decreased receptor activity, identifies the potential modulator as an inhibitor of chemokine receptor binding.
[0130] The activities of G protein effector molecules (e.g., adenylyl cyclase, phospholipase C, ion channels, and phosphodiesterases) are also amenable to assay.
[0131] Assays for the activities of these effector molecules have been previously described. For example, adenylyl cyclase, which catalyzes the synthesis of cyclic adenosine monophosphate (cAMP), is activated by G proteins. Therefore, ligand binding to a chemokine receptor that activates a G protein, which in turn activates adenylyl cyclase, can be detected by monitoring cAMP levels in a recombinant host cell of the invention. Implementing appropriate controls understood in the art, an elevated level of intracellular cAMP can be attributed to a ligand-induced increase in receptor activity, thereby identifying a ligand. Again using controls understood in the art, a relative reduction in the concentration of cAMP would indirectly identify an inhibitor of receptor activity. The concentration of cAMP can be measured by a commercial enzyme immunoassay. For example, the BioTrak Kit provides reagents for a competitive immunoassay (Amersham, Inc., Arlington Heights, Ill.). Using this kit according to the manufacturer's recommendations, a reaction is designed that involves competing unlabeled cAMP with cAMP conjugated to horseradish peroxidase. The unlabeled cAMP may be obtained, for example, from activated cells expressing the chemokine receptors of the invention. The two compounds compete for binding to an immobilized anti-cAMP antibody. After the competition reaction, the immobilized horseradish peroxidase-cAMP conjugate is quantitated by enzyme assay using a tetramethylbenzidine/H 2 O 2 single-pot substrate with detection of colored reaction products occurring at 450 nM. The results provide a basis for calculating the level of unlabeled cAMP, using techniques that are standard in the art. In addition to identifying ligands binding to chemokine receptors, the cAMP assay can also be used to identify modulators of chemokine receptor binding. Using recombinant host cells of the invention, the assay is performed as previously described, with the addition of a potential modulator of chemokine receptor activity. By using controls that are understood in the art, a relative increase or decrease in intracellular cAMP levels reflects the activation or inhibition of adenylyl cyclase activity. The level of adenylyl cyclase activity, in turn, reflects the relative activity of the chemokine receptor of interest. A relatively elevated level of chemokine receptor activity identifies an activator; a relatively reduced level of receptor activity identifies an inhibitor of chemokine receptor activity.
[0132] While the present invention has been described in terms of specific embodiments, it is understood that variations and modifications will occur to those skilled in the art. Accordingly, only such limitations as appear in the appended claims should be placed on the invention.
0
SEQUENCE LISTING
(1) GENERAL INFORMATION:
(iii) NUMBER OF SEQUENCES: 20
(2) INFORMATION FOR SEQ ID NO: 1:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 3383 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: cDNA
(ix) FEATURE:
(A) NAME/KEY: CDS
(B) LOCATION: 55..1110
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88C polynucleotide and amino acid
sequences”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 1:
AGAAGAGCTG AGACATCCGT TCCCCTACAA GAAACTCTCC CCGGGTGGAA CAAG ATG 57
Met
1
GAT TAT CAA GTG TCA AGT CCA ATC TAT GAC ATC AAT TAT TAT ACA TCG 105
Asp Tyr Gln Val Ser Ser Pro Ile Tyr Asp Ile Asn Tyr Tyr Thr Ser
5 10 15
GAG CCC TGC CAA AAA ATC AAT GTG AAG CAA ATC GCA GCC CGC CTC CTG 153
Glu Pro Cys Gln Lys Ile Asn Val Lys Gln Ile Ala Ala Arg Leu Leu
20 25 30
CCT CCG CTC TAC TCA CTG GTG TTC ATC TTT GGT TTT GTG GGC AAC ATG 201
Pro Pro Leu Tyr Ser Leu Val Phe Ile Phe Gly Phe Val Gly Asn Met
35 40 45
CTG GTC ATC CTC ATC CTG ATA AAC TGC AAA AGG CTG AAG AGC ATG ACT 249
Leu Val Ile Leu Ile Leu Ile Asn Cys Lys Arg Leu Lys Ser Met Thr
50 55 60 65
GAC ATC TAC CTG CTC AAC CTG GCC ATC TCT GAC CTG TTT TTC CTT CTT 297
Asp Ile Tyr Leu Leu Asn Leu Ala Ile Ser Asp Leu Phe Phe Leu Leu
70 75 80
ACT GTC CCC TTC TGG GCT CAC TAT GCT GCC GCC CAG TGG GAC TTT GGA 345
Thr Val Pro Phe Trp Ala His Tyr Ala Ala Ala Gln Trp Asp Phe Gly
85 90 95
AAT ACA ATG TGT CAA CTC TTG ACA GGG CTC TAT TTT ATA GGC TTC TTC 393
Asn Thr Met Cys Gln Leu Leu Thr Gly Leu Tyr Phe Ile Gly Phe Phe
100 105 110
TCT GGA ATC TTC TTC ATC ATC CTC CTG ACA ATC GAT AGG TAC CTG GCT 441
Ser Gly Ile Phe Phe Ile Ile Leu Leu Thr Ile Asp Arg Tyr Leu Ala
115 120 125
GTC GTC CAT GCT GTG TTT GCT TTA AAA GCC AGG ACG GTC ACC TTT GGG 489
Val Val His Ala Val Phe Ala Leu Lys Ala Arg Thr Val Thr Phe Gly
130 135 140 145
GTG GTG ACA AGT GTG ATC ACT TGG GTG GTG GCT GTG TTT GCG TCT CTC 537
Val Val Thr Ser Val Ile Thr Trp Val Val Ala Val Phe Ala Ser Leu
150 155 160
CCA GGA ATC ATC TTT ACC AGA TCT CAA AAA GAA GGT CTT CAT TAC ACC 585
Pro Gly Ile Ile Phe Thr Arg Ser Gln Lys Glu Gly Leu His Tyr Thr
165 170 175
TGC AGC TCT CAT TTT CCA TAC AGT CAG TAT CAA TTC TGG AAG AAT TTC 633
Cys Ser Ser His Phe Pro Tyr Ser Gln Tyr Gln Phe Trp Lys Asn Phe
180 185 190
CAG ACA TTA AAG ATA GTC ATC TTG GGG CTG GTC CTG CCG CTG CTT GTC 681
Gln Thr Leu Lys Ile Val Ile Leu Gly Leu Val Leu Pro Leu Leu Val
195 200 205
ATG GTC ATC TGC TAC TCG GGA ATC CTA AAA ACT CTG CTT CGG TGT CGA 729
Met Val Ile Cys Tyr Ser Gly Ile Leu Lys Thr Leu Leu Arg Cys Arg
210 215 220 225
AAT GAG AAG AAG AGG CAC AGG GCT GTG AGG CTT ATC TTC ACC ATC ATG 777
Asn Glu Lys Lys Arg His Arg Ala Val Arg Leu Ile Phe Thr Ile Met
230 235 240
ATT GTT TAT TTT CTC TTC TGG GCT CCC TAC AAC ATT GTC CTT CTC CTG 825
Ile Val Tyr Phe Leu Phe Trp Ala Pro Tyr Asn Ile Val Leu Leu Leu
245 250 255
AAC ACC TTC CAG GAA TTC TTT GGC CTG AAT AAT TGC AGT AGC TCT AAC 873
Asn Thr Phe Gln Glu Phe Phe Gly Leu Asn Asn Cys Ser Ser Ser Asn
260 265 270
AGG TTG GAC CAA GCT ATG CAG GTG ACA GAG ACT CTT GGG ATG ACG CAC 921
Arg Leu Asp Gln Ala Met Gln Val Thr Glu Thr Leu Gly Met Thr His
275 280 285
TGC TGC ATC AAC CCC ATC ATC TAT GCC TTT GTC GGG GAG AAG TTC AGA 969
Cys Cys Ile Asn Pro Ile Ile Tyr Ala Phe Val Gly Glu Lys Phe Arg
290 295 300 305
AAC TAC CTC TTA GTC TTC TTC CAA AAG CAC ATT GCC AAA CGC TTC TGC 1017
Asn Tyr Leu Leu Val Phe Phe Gln Lys His Ile Ala Lys Arg Phe Cys
310 315 320
AAA TGC TGT TCT ATT TTC CAG CAA GAG GCT CCC GAG CGA GCA AGC TCA 1065
Lys Cys Cys Ser Ile Phe Gln Gln Glu Ala Pro Glu Arg Ala Ser Ser
325 330 335
GTT TAC ACC CGA TCC ACT GGG GAG CAG GAA ATA TCT GTG GGC TTG 1110
Val Tyr Thr Arg Ser Thr Gly Glu Gln Glu Ile Ser Val Gly Leu
340 345 350
TGACACGGAC TCAAGTGGGC TGGTGACCCA GTCAGAGTTG TGCACATGGC TTAGTTTTCA 1170
TACACAGCCT GGGCTGGGGG TGGGGTGGGA GAGGTCTTTT TTAAAAGGAA GTTACTGTTA 1230
TAGAGGGTCT AAGATTCATC CATTTATTTG GCATCTGTTT AAAGTAGATT AGATCTTTTA 1290
AGCCCATCAA TTATAGAAAG CCAAATCAAA ATATGTTGAT GAAAAATAGC AACCTTTTTA 1350
TCTCCCCTTC ACATGCATCA AGTTATTGAC AAACTCTCCC TTCACTCCGA AAGTTCCTTA 1410
TGTATATTTA AAAGAAAGCC TCAGAGAATT GCTGATTCTT GAGTTTAGTG ATCTGAACAG 1470
AAATACCAAA ATTATTTCAG AAATGTACAA CTTTTTACCT AGTACAAGGC AACATATAGG 1530
TTGTAAATGT GTTTAAAACA GGTCTTTGTC TTGCTATGGG GAGAAAAGAC ATGAATATGA 1590
TTAGTAAAGA AATGACACTT TTCATGTGTG ATTTCCCCTC CAAGGTATGG TTAATAAGTT 1650
TCACTGACTT AGAACCAGGC GAGAGACTTG TGGCCTGGGA GAGCTGGGGA AGCTTCTTAA 1710
ATGAGAAGGA ATTTGAGTTG GATCATCTAT TGCTGGCAAA GACAGAAGCC TCACTGCAAG 1770
CACTGCATGG GCAAGCTTGG CTGTAGAAGG AGACAGAGCT GGTTGGGAAG ACATGGGGAG 1830
GAAGGACAAG GCTAGATCAT GAAGAACCTT GACGGCATTG CTCCGTCTAA GTCATGAGCT 1890
GAGCAGGGAG ATCCTGGTTG GTGTTGCAGA AGGTTTACTC TGTGGCCAAA GGAGGGTCAG 1950
GAAGGATGAG CATTTAGGGC AAGGAGACCA CCAACAGCCC TCAGGTCAGG GTGAGGATGG 2010
CCTCTGCTAA GCTCAAGGCG TGAGGATGGG AAGGAGGGAG GTATTCGTAA GGATGGGAAG 2070
GAGGGAGGTA TTCGTGCAGC ATATGAGGAT GCAGAGTCAG CAGAACTGGG GTGGATTTGG 2130
TTTGGAAGTG AGGGTCAGAG AGGAGTCAGA GAGAATCCCT AGTCTTCAAG CAGATTGGAG 2190
AAACCCTTGA AAAGACATCA AGCACAGAAG GAGGAGGAGG AGGTTTAGGT CAAGAAGAAG 2250
ATGGATTGGT GTAAAAGGAT GGGTCTGGTT TGCAGAGCTT GAACACAGTC TCACCCAGAC 2310
TCCAGGCTGT CTTTCACTGA ATGCTTCTGA CTTCATAGAT TTCCTTCCCA TCCCAGCTGA 2370
AATACTGAGG GGTCTCCAGG AGGAGACTAG ATTTATGAAT ACACGAGGTA TGAGGTCTAG 2430
GAACATACTT CAGCTCACAC ATGAGATCTA GGTGAGGATT GATTACCTAG TAGTCATTTC 2490
ATGGGTTGTT GGGAGGATTC TATGAGGCAA CCACAGGCAG CATTTAGCAC ATACTACACA 2550
TTCAATAAGC ATCAAACTCT TAGTTACTCA TTCAGGGATA GCACTGAGCA AAGCATTGAG 2610
CAAAGGGGTC CCATATAGGT GAGGGAAGCC TGAAAAACTA AGATGCTGCC TGCCCAGTGC 2670
ACACAAGTGT AGGTATCATT TTCTGCATTT AACCGTCAAT AGGCAAAGGG GGGAAGGGAC 2730
ATATTCATTT GGAAATAAGC TGCCTTGAGC CTTAAAACCC ACAAAAGTAC AATTTACCAG 2790
CCTCCGTATT TCAGACTGAA TGGGGGTGGG GGGGGCGCCT TAGGTACTTA TTCCAGATGC 2850
CTTCTCCAGA CAAACCAGAA GCAACAGAAA AAATCGTCTC TCCCTCCCTT TGAAATGAAT 2910
ATACCCCTTA GTGTTTGGGT ATATTCATTT CAAAGGGAGA GAGAGAGGTT TTTTTCTGTT 2970
CTTTCTCATA TGATTGTGCA CATACTTGAG ACTGTTTTGA ATTTGGGGGA TGGCTAAAAC 3030
CATCATAGTA CAGGTAAGGT GAGGGAATAG TAAGTGGTGA GAACTACTCA GGGAATGAAG 3090
GTGTCAGAAT AATAAGAGGT GCTACTGACT TTCTCAGCCT CTGAATATGA ACGGTGAGCA 3150
TTGTGGCTGT CAGCAGGAAG CAACGAAGGG AAATGTCTTT CCTTTTGCTC TTAAGTTGTG 3210
GAGAGTGCAA CAGTAGCATA GGACCCTACC CTCTGGGCCA AGTCAAAGAC ATTCTGACAT 3270
CTTAGTATTT GCATATTCTT ATGTATGTGA AAGTTACAAA TTGCTTGAAA GAAAATATGC 3330
ATCTAATAAA AAACACCTTC TAAAATAAAA AAAAAAAAAA AAAAAAAAAA AAA 3383
(2) INFORMATION FOR SEQ ID NO: 2:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 352 amino acids
(B) TYPE: amino acid
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: protein
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88C amino acid sequence”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 2:
Met Asp Tyr Gln Val Ser Ser Pro Ile Tyr Asp Ile Asn Tyr Tyr Thr
1 5 10 15
Ser Glu Pro Cys Gln Lys Ile Asn Val Lys Gln Ile Ala Ala Arg Leu
20 25 30
Leu Pro Pro Leu Tyr Ser Leu Val Phe Ile Phe Gly Phe Val Gly Asn
35 40 45
Met Leu Val Ile Leu Ile Leu Ile Asn Cys Lys Arg Leu Lys Ser Met
50 55 60
Thr Asp Ile Tyr Leu Leu Asn Leu Ala Ile Ser Asp Leu Phe Phe Leu
65 70 75 80
Leu Thr Val Pro Phe Trp Ala His Tyr Ala Ala Ala Gln Trp Asp Phe
85 90 95
Gly Asn Thr Met Cys Gln Leu Leu Thr Gly Leu Tyr Phe Ile Gly Phe
100 105 110
Phe Ser Gly Ile Phe Phe Ile Ile Leu Leu Thr Ile Asp Arg Tyr Leu
115 120 125
Ala Val Val His Ala Val Phe Ala Leu Lys Ala Arg Thr Val Thr Phe
130 135 140
Gly Val Val Thr Ser Val Ile Thr Trp Val Val Ala Val Phe Ala Ser
145 150 155 160
Leu Pro Gly Ile Ile Phe Thr Arg Ser Gln Lys Glu Gly Leu His Tyr
165 170 175
Thr Cys Ser Ser His Phe Pro Tyr Ser Gln Tyr Gln Phe Trp Lys Asn
180 185 190
Phe Gln Thr Leu Lys Ile Val Ile Leu Gly Leu Val Leu Pro Leu Leu
195 200 205
Val Met Val Ile Cys Tyr Ser Gly Ile Leu Lys Thr Leu Leu Arg Cys
210 215 220
Arg Asn Glu Lys Lys Arg His Arg Ala Val Arg Leu Ile Phe Thr Ile
225 230 235 240
Met Ile Val Tyr Phe Leu Phe Trp Ala Pro Tyr Asn Ile Val Leu Leu
245 250 255
Leu Asn Thr Phe Gln Glu Phe Phe Gly Leu Asn Asn Cys Ser Ser Ser
260 265 270
Asn Arg Leu Asp Gln Ala Met Gln Val Thr Glu Thr Leu Gly Met Thr
275 280 285
His Cys Cys Ile Asn Pro Ile Ile Tyr Ala Phe Val Gly Glu Lys Phe
290 295 300
Arg Asn Tyr Leu Leu Val Phe Phe Gln Lys His Ile Ala Lys Arg Phe
305 310 315 320
Cys Lys Cys Cys Ser Ile Phe Gln Gln Glu Ala Pro Glu Arg Ala Ser
325 330 335
Ser Val Tyr Thr Arg Ser Thr Gly Glu Gln Glu Ile Ser Val Gly Leu
340 345 350
(2) INFORMATION FOR SEQ ID NO: 3:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 1915 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: cDNA
(ix) FEATURE:
(A) NAME/KEY: CDS
(B) LOCATION: 362..1426
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88-2B polynucleotide and amino acid
sequences”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 3:
ATAATAATGA TTATTATATT GTTATCATTA TCTAGCCTGT TTTTTCCTGT TTTGTATTTC 60
TTCCTTTAAA TGCTTTCAGA AATCTGTATC CCCATTCTTC ACCACCACCC CACAACATTT 120
CTGCTTCTTT TCCCATGCCG GGTCATGCTA ACTTTGAAAG CTTCAGCTCT TTCCTTCCTC 180
AATCCTTTTC CTGGCACCTC TGATATGCCT TTTGAAATTC ATGTTAAAGA ATCCCTAGGC 240
TGCTATCACA TGTGGCATCT TTGTTGAGTA CATGAATAAA TCAACTGGTG TGTTTTACGA 300
AGGATGATTA TGCTTCATTG TGGGATTGTA TTTTTCTTCT TCTATCACAG GGAGAAGTGA 360
A ATG ACA ACC TCA CTA GAT ACA GTT GAG ACC TTT GGT ACC ACA TCC 406
Met Thr Thr Ser Leu Asp Thr Val Glu Thr Phe Gly Thr Thr Ser
1 5 10 15
TAC TAT GAT GAC GTG GGC CTG CTC TGT GAA AAA GCT GAT ACC AGA GCA 454
Tyr Tyr Asp Asp Val Gly Leu Leu Cys Glu Lys Ala Asp Thr Arg Ala
20 25 30
CTG ATG GCC CAG TTT GTG CCC CCG CTG TAC TCC CTG GTG TTC ACT GTG 502
Leu Met Ala Gln Phe Val Pro Pro Leu Tyr Ser Leu Val Phe Thr Val
35 40 45
GGC CTC TTG GGC AAT GTG GTG GTG GTG ATG ATC CTC ATA AAA TAC AGG 550
Gly Leu Leu Gly Asn Val Val Val Val Met Ile Leu Ile Lys Tyr Arg
50 55 60
AGG CTC CGA ATT ATG ACC AAC ATC TAC CTG CTC AAC CTG GCC ATT TCG 598
Arg Leu Arg Ile Met Thr Asn Ile Tyr Leu Leu Asn Leu Ala Ile Ser
65 70 75
GAC CTG CTC TTC CTC GTC ACC CTT CCA TTC TGG ATC CAC TAT GTC AGG 646
Asp Leu Leu Phe Leu Val Thr Leu Pro Phe Trp Ile His Tyr Val Arg
80 85 90 95
GGG CAT AAC TGG GTT TTT GGC CAT GGC ATG TGT AAG CTC CTC TCA GGG 694
Gly His Asn Trp Val Phe Gly His Gly Met Cys Lys Leu Leu Ser Gly
100 105 110
TTT TAT CAC ACA GGC TTG TAC AGC GAG ATC TTT TTC ATA ATC CTG CTG 742
Phe Tyr His Thr Gly Leu Tyr Ser Glu Ile Phe Phe Ile Ile Leu Leu
115 120 125
ACA ATC GAC AGG TAC CTG GCC ATT GTC CAT GCT GTG TTT GCC CTT CGA 790
Thr Ile Asp Arg Tyr Leu Ala Ile Val His Ala Val Phe Ala Leu Arg
130 135 140
GCC CGG ACT GTC ACT TTT GGT GTC ATC ACC AGC ATC GTC ACC TGG GGC 838
Ala Arg Thr Val Thr Phe Gly Val Ile Thr Ser Ile Val Thr Trp Gly
145 150 155
CTG GCA GTG CTA GCA GCT CTT CCT GAA TTT ATC TTC TAT GAG ACT GAA 886
Leu Ala Val Leu Ala Ala Leu Pro Glu Phe Ile Phe Tyr Glu Thr Glu
160 165 170 175
GAG TTG TTT GAA GAG ACT CTT TGC AGT GCT CTT TAC CCA GAG GAT ACA 934
Glu Leu Phe Glu Glu Thr Leu Cys Ser Ala Leu Tyr Pro Glu Asp Thr
180 185 190
GTA TAT AGC TGG AGG CAT TTC CAC ACT CTG AGA ATG ACC ATC TTC TGT 982
Val Tyr Ser Trp Arg His Phe His Thr Leu Arg Met Thr Ile Phe Cys
195 200 205
CTC GTT CTC CCT CTG CTC GTT ATG GCC ATC TGC TAC ACA GGA ATC ATC 1030
Leu Val Leu Pro Leu Leu Val Met Ala Ile Cys Tyr Thr Gly Ile Ile
210 215 220
AAA ACG CTG CTG AGG TGC CCC AGT AAA AAA AAG TAC AAG GCC ATC CGG 1078
Lys Thr Leu Leu Arg Cys Pro Ser Lys Lys Lys Tyr Lys Ala Ile Arg
225 230 235
CTC ATT TTT GTC ATC ATG GCG GTG TTT TTC ATT TTC TGG ACA CCC TAC 1126
Leu Ile Phe Val Ile Met Ala Val Phe Phe Ile Phe Trp Thr Pro Tyr
240 245 250 255
AAT GTG GCT ATC CTT CTC TCT TCC TAT CAA TCC ATC TTA TTT GGA AAT 1174
Asn Val Ala Ile Leu Leu Ser Ser Tyr Gln Ser Ile Leu Phe Gly Asn
260 265 270
GAC TGT GAG CGG AGC AAG CAT CTG GAC CTG GTC ATG CTG GTG ACA GAG 1222
Asp Cys Glu Arg Ser Lys His Leu Asp Leu Val Met Leu Val Thr Glu
275 280 285
GTG ATC GCC TAC TCC CAC TGC TGC ATG AAC CCG GTG ATC TAC GCC TTT 1270
Val Ile Ala Tyr Ser His Cys Cys Met Asn Pro Val Ile Tyr Ala Phe
290 295 300
GTT GGA GAG AGG TTC CGG AAG TAC CTG CGC CAC TTC TTC CAC AGG CAC 1318
Val Gly Glu Arg Phe Arg Lys Tyr Leu Arg His Phe Phe His Arg His
305 310 315
TTG CTC ATG CAC CTG GGC AGA TAC ATC CCA TTC CTT CCT AGT GAG AAG 1366
Leu Leu Met His Leu Gly Arg Tyr Ile Pro Phe Leu Pro Ser Glu Lys
320 325 330 335
CTG GAA AGA ACC AGC TCT GTC TCT CCA TCC ACA GCA GAG CCG GAA CTC 1414
Leu Glu Arg Thr Ser Ser Val Ser Pro Ser Thr Ala Glu Pro Glu Leu
340 345 350
TCT ATT GTG TTT TAGGTCAGAT GCAGAAAATT GCCTAAAGAG GAAGGACCAA 1466
Ser Ile Val Phe
355
GGAGATGAAG CAAACACATT AAGCCTTCCA CACTCACCTC TAAAACAGTC CTTCAAACTT 1526
CCAGTGCAAC ACTGAAGCTC TTGAAGACAC TGAAATATAC ACACAGCAGT AGCAGTAGAT 1586
GCATGTACCC TAAGGTCATT ACCACAGGCC AGGGGCTGGG CAGCGTACTC ATCATCAACC 1646
CTAAAAAGCA GAGCTTTGCT TCTCTCTCTA AAATGAGTTA CCTACATTTT AATGCACCTG 1706
AATGTTAGAT AGTTACTATA TGCCGCTACA AAAAGGTAAA ACTTTTTATA TTTTATACAT 1766
TAACTTCAGC CAGCTATTGA TATAAATAAA ACATTTTCAC ACAATACAAT AAGTTAACTA 1826
TTTTATTTTC TAATGTGCCT AGTTCTTTCC CTGCTTAATG AAAAGCTTGT TTTTTCAGTG 1886
TGAATAAATA ATCGTAAGCA ACAAAAAAA 1915
(2) INFORMATION FOR SEQ ID NO: 4:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 355 amino acids
(B) TYPE: amino acid
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: protein
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88-2B amino acid sequence”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 4:
Met Thr Thr Ser Leu Asp Thr Val Glu Thr Phe Gly Thr Thr Ser Tyr
1 5 10 15
Tyr Asp Asp Val Gly Leu Leu Cys Glu Lys Ala Asp Thr Arg Ala Leu
20 25 30
Met Ala Gln Phe Val Pro Pro Leu Tyr Ser Leu Val Phe Thr Val Gly
35 40 45
Leu Leu Gly Asn Val Val Val Val Met Ile Leu Ile Lys Tyr Arg Arg
50 55 60
Leu Arg Ile Met Thr Asn Ile Tyr Leu Leu Asn Leu Ala Ile Ser Asp
65 70 75 80
Leu Leu Phe Leu Val Thr Leu Pro Phe Trp Ile His Tyr Val Arg Gly
85 90 95
His Asn Trp Val Phe Gly His Gly Met Cys Lys Leu Leu Ser Gly Phe
100 105 110
Tyr His Thr Gly Leu Tyr Ser Glu Ile Phe Phe Ile Ile Leu Leu Thr
115 120 125
Ile Asp Arg Tyr Leu Ala Ile Val His Ala Val Phe Ala Leu Arg Ala
130 135 140
Arg Thr Val Thr Phe Gly Val Ile Thr Ser Ile Val Thr Trp Gly Leu
145 150 155 160
Ala Val Leu Ala Ala Leu Pro Glu Phe Ile Phe Tyr Glu Thr Glu Glu
165 170 175
Leu Phe Glu Glu Thr Leu Cys Ser Ala Leu Tyr Pro Glu Asp Thr Val
180 185 190
Tyr Ser Trp Arg His Phe His Thr Leu Arg Met Thr Ile Phe Cys Leu
195 200 205
Val Leu Pro Leu Leu Val Met Ala Ile Cys Tyr Thr Gly Ile Ile Lys
210 215 220
Thr Leu Leu Arg Cys Pro Ser Lys Lys Lys Tyr Lys Ala Ile Arg Leu
225 230 235 240
Ile Phe Val Ile Met Ala Val Phe Phe Ile Phe Trp Thr Pro Tyr Asn
245 250 255
Val Ala Ile Leu Leu Ser Ser Tyr Gln Ser Ile Leu Phe Gly Asn Asp
260 265 270
Cys Glu Arg Ser Lys His Leu Asp Leu Val Met Leu Val Thr Glu Val
275 280 285
Ile Ala Tyr Ser His Cys Cys Met Asn Pro Val Ile Tyr Ala Phe Val
290 295 300
Gly Glu Arg Phe Arg Lys Tyr Leu Arg His Phe Phe His Arg His Leu
305 310 315 320
Leu Met His Leu Gly Arg Tyr Ile Pro Phe Leu Pro Ser Glu Lys Leu
325 330 335
Glu Arg Thr Ser Ser Val Ser Pro Ser Thr Ala Glu Pro Glu Leu Ser
340 345 350
Ile Val Phe
355
(2) INFORMATION FOR SEQ ID NO: 5:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 34 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “V28degf2”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 5:
GACGGATCCA TYGAYAGRTA CCTGGCYATY GTCC 34
(2) INFORMATION FOR SEQ ID NO: 6:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 32 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “V28degr2”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 6:
GCTAAGCTTT TRTAGGGDGT CCAYAAGAGY AA 32
(2) INFORMATION FOR SEQ ID NO: 7:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 21 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88c-r4”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 7:
GATAAGCCTC ACAGCCCTGT G 21
(2) INFORMATION FOR SEQ ID NO: 8:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 28 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88c-rlb”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 8:
GCTAAGCTTG ATGACTATCT TTAATGTC 28
(2) INFORMATION FOR SEQ ID NO: 9:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 27 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88-2B-3”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 9:
CCCTCTAGAC TAAAACACAA TAGAGAG 27
(2) INFORMATION FOR SEQ ID NO: 10:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 30 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88-2B-5”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 10:
GCTAAGCTTA TCACAGGGAG AAGTGAAATG 30
(2) INFORMATION FOR SEQ ID NO: 11:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 20 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88-2B-f1”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 11:
AGTGCTAGCA GCTCTTCCTG 20
(2) INFORMATION FOR SEQ ID NO: 12:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 20 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88-2B-r1”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 12:
CAGCAGCGTT TTGATGATTC 20
(2) INFORMATION FOR SEQ ID NO: 13:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 19 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88C-f1”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 13:
TGTGTTTGCT TTAAAAGCC 19
(2) INFORMATION FOR SEQ ID NO: 14:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 17 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “88C-r3”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 14:
TAAGCCTCAC AGCCCTG 17
(2) INFORMATION FOR SEQ ID NO: 15:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 28 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “CCCKR1(2)-5 Primer”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 15:
CGTAAGCTTA GAGAAGCCGG GATGGGAA 28
(2) INFORMATION FOR SEQ ID NO: 16:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 25 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA
(iv) ANTI-SENSE: YES
(ix) FEATURE:
(A) NAME/KEY: misc_feature
(D) OTHER INFORMATION: /= “CCCKR-3 Primer”
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 16:
GCCTCTAGAG TCAGAGACCA GCAGA 25
(2) INFORMATION FOR SEQ ID NO: 17:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 28 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA (genomic)
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 17:
GACAAGCTTC ACAGGGTGGA ACAAGATG 28
(2) INFORMATION FOR SEQ ID NO: 18:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 27 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: DNA (genomic)
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 18:
GTCTCTAGAC CACTTGAGTC CGTGTCA 27
(2) INFORMATION FOR SEQ ID NO: 19:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 1059 base pairs
(B) TYPE: nucleic acid
(C) STRANDEDNESS: single
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: cDNA
(ix) FEATURE:
(A) NAME/KEY: CDS
(B) LOCATION: 1..1056
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 19:
ATG GAC TAT CAA GTG TCA AGT CCA ACC TAT GAC ATC GAT TAT TAT ACA 48
Met Asp Tyr Gln Val Ser Ser Pro Thr Tyr Asp Ile Asp Tyr Tyr Thr
1 5 10 15
TCG GAA CCC TGC CAA AAA ATC AAT GTG AAA CAA ATC GCA GCC CGC CTC 96
Ser Glu Pro Cys Gln Lys Ile Asn Val Lys Gln Ile Ala Ala Arg Leu
20 25 30
CTG CCT CCG CTC TAC TCA CTG GTG TTC ATC TTT GGT TTT GTG GGC AAC 144
Leu Pro Pro Leu Tyr Ser Leu Val Phe Ile Phe Gly Phe Val Gly Asn
35 40 45
ATA CTG GTC GTC CTC ATC CTG ATA AAC TGC AAA AGG CTG AAA AGC ATG 192
Ile Leu Val Val Leu Ile Leu Ile Asn Cys Lys Arg Leu Lys Ser Met
50 55 60
ACT GAC ATC TAC CTG CTC AAC CTG GCC ATC TCT GAC CTG CTT TTC CTT 240
Thr Asp Ile Tyr Leu Leu Asn Leu Ala Ile Ser Asp Leu Leu Phe Leu
65 70 75 80
CTT ACT GTC CCC TTC TGG GCT CAC TAT GCT GCT GCC CAG TGG GAC TTT 288
Leu Thr Val Pro Phe Trp Ala His Tyr Ala Ala Ala Gln Trp Asp Phe
85 90 95
GGA AAT ACA ATG TGT CAA CTC TTG ACA GGG CTC TAT TTT ATA GGC TTC 336
Gly Asn Thr Met Cys Gln Leu Leu Thr Gly Leu Tyr Phe Ile Gly Phe
100 105 110
TTC TCT GGA ATC TTC TTC ATC ATC CTC CTG ACA ATC GAT AGG TAC CTG 384
Phe Ser Gly Ile Phe Phe Ile Ile Leu Leu Thr Ile Asp Arg Tyr Leu
115 120 125
GCT ATC GTC CAT GCT GTG TTT GCT TTA AAA GCC AGG ACA GTC ACC TTT 432
Ala Ile Val His Ala Val Phe Ala Leu Lys Ala Arg Thr Val Thr Phe
130 135 140
GGG GTG GTG ACA AGT GTG ATC ACT TGG GTG GTG GCT GTG TTT GCC TCT 480
Gly Val Val Thr Ser Val Ile Thr Trp Val Val Ala Val Phe Ala Ser
145 150 155 160
CTC CCA GGA ATC ATC TTT ACC AGA TCT CAG AGA GAA GGT CTT CAT TAC 528
Leu Pro Gly Ile Ile Phe Thr Arg Ser Gln Arg Glu Gly Leu His Tyr
165 170 175
ACC TGC AGC TCT CAT TTT CCA TAC AGT CAG TAT CAA TTC TGG AAG AAT 576
Thr Cys Ser Ser His Phe Pro Tyr Ser Gln Tyr Gln Phe Trp Lys Asn
180 185 190
TTT CAG ACA TTA AAG ATG GTC ATC TTG GGG CTG GTC CTG CCG CTG CTT 624
Phe Gln Thr Leu Lys Met Val Ile Leu Gly Leu Val Leu Pro Leu Leu
195 200 205
GTC ATG GTC ATC TGC TAC TCG GGA ATC CTG AAA ACT CTG CTT CGG TGT 672
Val Met Val Ile Cys Tyr Ser Gly Ile Leu Lys Thr Leu Leu Arg Cys
210 215 220
CGA AAC GAG AAG AAG AGG CAC AGG GCT GTG AGG CTT ATC TTC ACC ATC 720
Arg Asn Glu Lys Lys Arg His Arg Ala Val Arg Leu Ile Phe Thr Ile
225 230 235 240
ATG ATT GTT TAT TTT CTC TTG TGG GCT CCC TAC AAC ATT GTC CTT CTC 768
Met Ile Val Tyr Phe Leu Leu Trp Ala Pro Tyr Asn Ile Val Leu Leu
245 250 255
CTG AAC ACC TTC CAG GAA TTC TTT GGC CTG AAT AAT TGC AGT AGC TCT 816
Leu Asn Thr Phe Gln Glu Phe Phe Gly Leu Asn Asn Cys Ser Ser Ser
260 265 270
AAC AGG TTG GAC CAA GCC ATG CAG GTG ACA GAG ACT CTT GGG ATG ACA 864
Asn Arg Leu Asp Gln Ala Met Gln Val Thr Glu Thr Leu Gly Met Thr
275 280 285
CAC TGC TGC ATC AAC CCC ATC ATC TAT GCC TTT GTC GGG GAG AAG TTC 912
His Cys Cys Ile Asn Pro Ile Ile Tyr Ala Phe Val Gly Glu Lys Phe
290 295 300
AGA AAC TAC CTC TTA GTC TTC TTC CAA AAG CAC ATT GCC AAA CGC TTC 960
Arg Asn Tyr Leu Leu Val Phe Phe Gln Lys His Ile Ala Lys Arg Phe
305 310 315 320
TGC AAA TGC TGT TCC ATT TTC CAG CAA GAG GCT CCC GAG CGA GCA AGT 1008
Cys Lys Cys Cys Ser Ile Phe Gln Gln Glu Ala Pro Glu Arg Ala Ser
325 330 335
TCA GTT TAC ACC CGA TCC ACT GGG GAG CAG GAA ATA TCT GTG GGC TTG 1056
Ser Val Tyr Thr Arg Ser Thr Gly Glu Gln Glu Ile Ser Val Gly Leu
340 345 350
TGA 1059
(2) INFORMATION FOR SEQ ID NO: 20:
(i) SEQUENCE CHARACTERISTICS:
(A) LENGTH: 352 amino acids
(B) TYPE: amino acid
(D) TOPOLOGY: linear
(ii) MOLECULE TYPE: protein
(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 20:
Met Asp Tyr Gln Val Ser Ser Pro Thr Tyr Asp Ile Asp Tyr Tyr Thr
1 5 10 15
Ser Glu Pro Cys Gln Lys Ile Asn Val Lys Gln Ile Ala Ala Arg Leu
20 25 30
Leu Pro Pro Leu Tyr Ser Leu Val Phe Ile Phe Gly Phe Val Gly Asn
35 40 45
Ile Leu Val Val Leu Ile Leu Ile Asn Cys Lys Arg Leu Lys Ser Met
50 55 60
Thr Asp Ile Tyr Leu Leu Asn Leu Ala Ile Ser Asp Leu Leu Phe Leu
65 70 75 80
Leu Thr Val Pro Phe Trp Ala His Tyr Ala Ala Ala Gln Trp Asp Phe
85 90 95
Gly Asn Thr Met Cys Gln Leu Leu Thr Gly Leu Tyr Phe Ile Gly Phe
100 105 110
Phe Ser Gly Ile Phe Phe Ile Ile Leu Leu Thr Ile Asp Arg Tyr Leu
115 120 125
Ala Ile Val His Ala Val Phe Ala Leu Lys Ala Arg Thr Val Thr Phe
130 135 140
Gly Val Val Thr Ser Val Ile Thr Trp Val Val Ala Val Phe Ala Ser
145 150 155 160
Leu Pro Gly Ile Ile Phe Thr Arg Ser Gln Arg Glu Gly Leu His Tyr
165 170 175
Thr Cys Ser Ser His Phe Pro Tyr Ser Gln Tyr Gln Phe Trp Lys Asn
180 185 190
Phe Gln Thr Leu Lys Met Val Ile Leu Gly Leu Val Leu Pro Leu Leu
195 200 205
Val Met Val Ile Cys Tyr Ser Gly Ile Leu Lys Thr Leu Leu Arg Cys
210 215 220
Arg Asn Glu Lys Lys Arg His Arg Ala Val Arg Leu Ile Phe Thr Ile
225 230 235 240
Met Ile Val Tyr Phe Leu Leu Trp Ala Pro Tyr Asn Ile Val Leu Leu
245 250 255
Leu Asn Thr Phe Gln Glu Phe Phe Gly Leu Asn Asn Cys Ser Ser Ser
260 265 270
Asn Arg Leu Asp Gln Ala Met Gln Val Thr Glu Thr Leu Gly Met Thr
275 280 285
His Cys Cys Ile Asn Pro Ile Ile Tyr Ala Phe Val Gly Glu Lys Phe
290 295 300
Arg Asn Tyr Leu Leu Val Phe Phe Gln Lys His Ile Ala Lys Arg Phe
305 310 315 320
Cys Lys Cys Cys Ser Ile Phe Gln Gln Glu Ala Pro Glu Arg Ala Ser
325 330 335
Ser Val Tyr Thr Arg Ser Thr Gly Glu Gln Glu Ile Ser Val Gly Leu
340 345 350 | The present invention provides polynucleotides that encode the chemokine receptors 88-2B or 88C and materials and methods for the recombinant production of these two chemokine receptors. Also provided are assays utilizing the polynucleotides which facilitate the identification of ligands and modulators of the chemokine receptors. Receptor fragments, ligands, modulators, and antibodies are useful in the detection and treatment of disease states associated with the chemokine receptors such as atherosclerosis, rheumatoid arthritis, tumor growth suppression, asthma, viral infection, AIDS, and other inflammatory conditions. | 2 |
FIELD OF THE INVENTION
This invention relates to a composition and method for the controlled release of biologically active agricultural agents such as fertilizers and more specifically pesticides. More specifically, the invention concerns the absorption, on a particular type of material, of certain organic agents such as herbicides and the like which would be released over a time span once the product is dispersed in the field.
BACKGROUND OF THE INVENTION
The basic principle in controlled release is the entrapment of an active ingredient by some method in such a way that slow escape of the ingredient to the environment is allowed, see Agis Kydonieus, Controlled Release Technologies: Methods, Theory and Applications, pages 2 and 4, CRC Press, Inc. 1980.
The use of time-release agents for agricultural purposes in cultivated field environments is known. In many instances the means used for controlling release of the active ingredient over a period of time has been chosen to reduce the exposure thereof to the environment so as to prevent its being quickly washed away by water or to prevent rapid evaporation. Consequently, the effort has frequently been to coat the active ingredient with one or more insoluble materials, thereby to slow down its movement into the environment.
Thus, for example, U.S. Pat. No. 4,082,533 discloses a product having a core of a urea fertilizer and two water-insoluble coatings, viz., cement and a thermoplastic polymer/wax blend. The patentee of U.S. Pat. No. 3,050,385 bonds the fertilizer to oil shale as an insolubilizing and support material. U.S. Pat. No. 3,502,458 uses a fertilizer, a dry fibrous organic material such as sawdust and a bonding agent such as a urea-formaldehyde resin or a Cumar V-3 resin. U.S. Pat. No. 3,192,031 discloses urea (fertilizer) particles precoated with a thin film of a diatomaceous earth (natural clays, e.g. bentonite, are briefly mentioned) and then coated with wax. U.S. Pat. No. 3,062,637 describes an agricultural granule for insecticide, herbicide and plant nutrient purposes, which comprises the active ingredient, a mineral carrier such as diatomaceous earth and as a binder a colloidal clay, viz., attapulgite or sepiolite.
On the other hand, water-immiscible herbicides and the like are used which are formed into aqueous dispersions with the aid of emulsifiers and then encapsulated, as disclosed in U.S. Pat. No. 4,280,833. Controlled release pesticides are also formulated with silanes as shown in U.S. Pat. Nos. 4,282,207 and 4,283,387.
In the medical/biochemical area, compositions are used in which the medically active components in solution are releasably enclosed within a container at least part of which is a microporous membrane. In this category fall U.S. Pat. Nos. 4,067,961 and 4,145,408.
A solid pesticide adapted to be progressively disintegrated by contact with a stream of water is described in U.S. Pat. No. 4,182,620. It comprises a pesticide, a solid non-hydrophilic filler such as talcum and a starch. Kaolin is included in some of the compositions.
U.S. Pat. No. 4,219,349 discloses a plant nutrient composition, for potted plants containing little mineral soil but instead containing growth media, and comprising various plant nutrients on a calcined clay which may be bentonite or attapulgite. As described, the compositions are prepared by mixing the calcined clay granules with a solution of the nutrients. The compositions are applied to the growth media in plant nourishing amounts. The patentee theorizes that when the plant nutrient compositions are incorporated into the growth media they will equilibrate with the solution bathing the roots and the media; the plant roots exchange protons and bicarbonates for the needed ions in solution which in turn exchange with the micronutrients on the clay granules to supply nutrients to complete the cycle.
Thus, the plant nutrient compositions function via an ion exchange process with plant roots in an aqueous medium.
In a series of U.S. patents to Gary W. Beall, assigned to Radecca, Inc., which are:
No. 4,470,912
No. 4,473,477
No. 4,517,094
No. 4,549,966
a method is described for absorbing organic contaminants on an organoclay from an aqueous composition or from solid or liquid wastes.
Organoclays are well known in the art, especially as gelling agents for paints and the like. In this invention, the term "organoclay" refers to various clay types, e.g. smectites, that have organo ammonium ions substituted for cations between the clay layers. The term "organo ammonium ion" refers to a substituted ammonium ion in which one or more hydrogen atoms are replaced by an organic group. The organoclays are modified clays which exhibit in organic liquids, some of those characteristics which untreated clays exhibit in water. For example, they will swell in many organic liquids and will form stable gels and colloidal dispersions. Organoclays are organophilic or oleophilic. An extensive discussion may be found in the above-mentioned patents to Beall.
According to the invention, organic bioactive agents such as fertilizers and pesticides, e.g. insecticides, herbicides, bactericides, growth regulators and fungicides, may be controllably released by a unique mechanism which is independent on the absorptive/desorptive characteristics of a particular material on which the agents are provided.
SUMMARY OF THE INVENTION
In accordance with the invention, a controlled release composition is provided which comprises an organoclay on which an organic biologically active material has been absorbed. The method of application involves exposing the organoclay to a high concentration of the active ingredient to cause it to be absorbed on the organoclay and then distributing the product in agricultural fields where it is needed. This function of organoclays is surprising since they have previously been used primarily as gelling agents; also they have been proposed in the Beall patents for absorbing organic contaminants but not for slow release or distribution of biologically active materials where needed, particularly for improving agriculture.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flowsheet illustrating how organoclays can be used in controlled release applications;
FIG. 2 is a graph showing the release of a biologically active material from two different organoclays on which it has been absorbed, in which the percent of the active material which has been released from the organoclay exposed to a controlled flow of nitrogen is plotted against time, in days; and
FIG. 3 shows the amount of a biologically active material present in a stream of nitrogen continually passed over the active material alone as well as the amount present in a separate flow passed over the active material which has been absorbed onto an organoclay.
DETAILED DESCRIPTION
The preferred clay substrates for use in this invention are the smectite type clays, particularly the smectite type clays which have a cation exchange capacity of at least 75 milliequivalents per 100 grams of clay. Useful clays for such purposes include the naturally occurring Wyoming variety of swelling bentonite and similar clays, and hectorite, which is a swelling magnesium-lithium silicate clay. The clays are preferably converted to the sodium form if they are not already in this form. This can be effected by a cation exchange reaction with a soluble sodium compound. These methods are well known in the art. Smectite-type clays prepared synthetically can also be utilized.
Generally, the quaternary ammonium salt reacted with the clay has organic groups attached to the quaternary nitrogen which may range from aliphatic hydrocarbon of from 1 to 24 carbons to aromatic organic molecules, such as benzyl groups that could have a host of groups substituted on the benzyl ring. The amount of alkyl ammonium salt substituted on the clay can vary between 0.5% to 50%.
In particular, the organoclay used in this invention may comprise one or more of the following ammonium cation modified montmorillonite clays: ##STR1## wherein R 1 is an alkyl group having at least 4 carbon atoms, preferably at least 10 carbon atoms and up to, for example, 24 carbon atoms, more preferably having a chain length of from 12 to 18 carbon atoms; R 2 is hydrogen, benzyl or an alkyl group of at least 4 carbon atoms, preferably at least 10 carbon atoms and up to, for example, 24 carbon atoms, more preferably a chain length of from 12 to 18 carbon atoms; and R 3 and R 4 are each hydrogen or lower alkyl groups, viz., they contain carbon chains of from 1 to 4 atoms, and preferably are methyl groups. Hydroxyethoxy, hydroxypropoxy groups and their corresponding poly-oxy homologs are also especially useful in some applications.
Other organoclays utilizable in the invention include benzyl organoclays such as dimethyl benzyl (hydrogenated tallow) ammonium bentonite; methyl benzyl di(hydrogenated tallow) ammonium bentonite; and more generally quaternary ammonium cation modified montmorillonite clays represented by the formula: ##STR2## wherein R 1 is CH 3 or C 6 H 5 CH 2 ; R 2 is C 6 H 5 CH 2 ; and R 3 and R 4 are alkyl groups containing long chain alkyl radicals having 14 to 22 carbon atoms, and most preferably wherein 20% to 35% of said long chain alkyl radicals contain 16 carbon atoms and 60% to 75% of said long chain alkyl radicals contain 18 carbon atoms.
The montmorillonite clays which may be so modified are the principal constituents of bentonite rock. Modified montmorillonite clays of this type (i.e. organoclays) are commercially available from Southern Clay Products, Inc., Gonzales, Tex., under such trade designations as CLAYTONE 34 and 40, and are available from NL Industries, Inc. New York, N.Y., under such trade designations as BENTONE 27, 34, and 38. The preferred organoclays utilized in this invention, are the higher dialky dimethyl ammonium organoclays such as dimethyl di(hydrogenated tallow) ammonium bentonite; the benzyl ammonium organoclays, such as dimethyl benzyl (hydrogenated tallow) ammonium bentonite; and hydroxyethoxy ammonium organoclays such as methyl bis(2-hydroxyethoxy)octadecyl ammonium bentonite.
FIG. 1 illustrates how organoclays can be used in controlled release applications. The organoclay is first exposed to a high concentration of the active ingredient. The active ingredient is absorbed into the clay interlayers and held there by capillary and/or solvation forces until an equilibrium concentration is reached within the organoclay. This equilibrium concentration depends on the concentration of the active in contact with the organoclay. As the concentration of the active in contact with the clay decreases, so does the capacity of the clay for the active. Thus, when the clay which has been in contact with a high active concentration is removed to an environment which is low in active, the clay gives off its absorbed active until a new equilibrium is reached with the new environment (which may be air, water, etc.). Thus, if the organoclay is placed in pure liquid pesticide, it will absorb some quantity of the pesticide. If it is then removed to the open atmosphere, it will allow the absorbed pesticide to escape into the environment. However, the rate of release (or escape) will be much slower than if one simply left a drop of the same amount of pesticide out on a dish (assuming a volatile pesticide is used). Thus, the pesticide absorbed on organoclay gives a more prolonged effect than the pesticide by itself.
The method of contacting the organoclay with the organic biologically active material may be any of those described in U.S. Pat. No. 4,549,966, for example, by using flow through columns and batch methods, e.g., flowing the organic, which may be in a concentrated solution, through a packed column of organoclay; or by contacting stirred beds of organoclay with the treating composition; or by adding to the latter the organoclay as a finely divided powder and after a sufficient time separating it by known methods such as filtration, centrifugation, etc. It is also possible to mix the organic biologically active material with the quaternary ammonium compound prior to reacting the quaternary ammonium compound with the bentonite to form the organoclay.
Application of the product in fields may be done by any of the conventional methods, e.g., broadcasting from the air, spraying, etc.
The invention is demonstrated in the following examples which are to be considered illustrative but not limitative.
EXAMPLE 1
Two samples of S-Ethyl-N,N,dipropylthiocarbamate (ENDT) were mixed respectively with two different, dry powdered organoclays to form controlled release compositions and allowed to sit overnight. The ratio of organoclay to ENDT was 2:1 in each case. The weight loss of three separate containers (pure ENDT and the two ENDT/organoclay mixtures) was measured over a period of 10 days. Each container was kept in a stream of nitrogen flowing at 6000 cc/min. The results are shown in FIG. 2. The organoclays clearly slow the release of ENDT.
The organoclays in this example were both made from the same bentonite. However, organoclay A contained 100 meq/100 g clay of the diemthyldi(hydrogenated tallow) ammonium cation whereas organoclay B contained 92 meq/100 g clay of the trimethyldodecyl ammonium chloride cation. Clearly, the type of organic ammonium compound used to make the organoclay can have a significant effect on the rate of release of some absorbed organic materials.
ENDT is used commercially as a herbicide, especially in the production of corn.
EXAMPLE 2
S-Ethyldiisobutylthiocarbamate (EDBT) sold under the tradename "Genate" was mixed with organoclay A in the same manner as in Example 1. The EDBT/organoclay composition was then placed in a nitrogen air stream flowing at 6,000 cc/min. The amount of EDBT in the nitrogen stream downflow from the EDBT/organoclay composition was measured after one hour and then on selected days thereafter for 25 days. Gas chromatography was used to measure the EDBT.
FIG. 3 shows that the release of EDBT is dramatically prolonged by the organoclay relative to evaporation of the pure liquid EDBT.
Like ENDT, EDBT is an effective herbicide used in controlling weeds in corn production.
It can be seen that the use of organoclays in controlled release pesticides is a novel and useful approach. The behavior of the product is largely dependent on the intrinsic absorptive/desorptive properties of the organoclay for organic substances and thus is not suggested by other types of carriers/supports. It is not necessary to mix the pesticide with highly insoluble materials of the nature of cement, oil shale, and the like; or on the other hand to make a dispersion thereof; or to enclose the pesticide within a membrance sac. In fact, it is not mandatory to formulate the two essential ingredients with other ingredients, although such is not precluded in the subject invention. The subject invention is operable in a simplified mode; works by a distinctive, novel mechanism; permits the controlled passage into the environment of an active substance because of the initial dilution of the biologically active ingredient with the admixed innocuous solid clay and the slow release feature, thus avoiding high concentrations of the active agent, and is unique in many of its aspects. | A controlled release composition is prepared by contacting an organoclay with a biologically active material in concentrated form to cause absorption of the active material on the organoclay. The resulting product releases the active agent slowly, over a period of time, when exposed to the open atmosphere, for instance on being distributed over cultivated fields. | 8 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The invention relates to a magnetic resonance apparatus, including a mainly cylindrical RF coil which has a central axis extending in its longitudinal direction and having a number of axial conductor elements which extend parallel to the central axis across a mainly cylindrical surface, and also end conductor elements which extend around the central axis near the ends of the axial conductor elements, the axial conductor elements extending pair-wise diametrically relative to the central axis, the coil being arranged to generate a substantially cosinusoidal current distribution as a function of the position of the axial conductor elements on the circumference of the cylinder in order to enable a substantially uniform RF magnetic field, oriented perpendicularly to the cylinder axis, to be generated and/or received.
2. Description of the Related Art
An example of such a magnetic resonance apparatus is known from EP-B-0 141 383. Capacitive elements are included in the axial conductor elements in the known apparatus. The RF coil can be represented as a ladder network consisting of a number of identical elements, each of which comprises a combination of self-inductances and capacitances. The values of the capacitances are determined mainly by the values of the capacitors included in the axial conductor elements, the values of the self-inductances being determined mainly by the self-inductances of the conductors constituting the RF coil and by the mutual inductances between these conductors. The resonance frequency of the ladder network, determining the frequency at which the RF coil can be used, can be determined by the designer by way of a suitable choice of the values of the capacitances and the self-inductances in said elements of the network. As is known, the resonance frequency is inversely proportional to the square root of the product of the self-inductance and the capacitance. In the known apparatus the range of values wherefrom the resonance frequency can be chosen is limited because the value of the capacitance cannot be arbitrarily high and with given dimensions of the RF coil the value of the self-inductance is substantially impossible to vary. As a result, the known apparatus is not suitable for so-called low-field MRI wherein the RF coil must be tuned to a comparatively low frequency. Examinations utilizing the so-called Overhauser effect also use low frequencies; for example, see EP-A-0 409 292. For such measurements the desired resonance frequency of the RF coil may be of the order of magnitude of some hundreds of kHz.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an apparatus of the kind set forth in which the resonance frequency of the RF coil can be chosen comparatively independently of the dimensions of this coil, so that comparatively low resonance frequencies are also possible. To achieve this, the apparatus in accordance with the invention is characterized in that each of the end conductor elements consists of a number of loop conductor segments which corresponds to the number of pairs of axial conductor elements, each loop conductor segment extending through an arc of 180° around the central axis and electrically interconnecting corresponding ends of a pair of axial conductor elements diametrically situated relative to the central axis, each pair of axial conductor elements constituting, in conjunction with the loop conductor segments connected to their ends, a coil element composed of a number of turns of an elongate electric conductor. As a result of these steps, the self-inductance of the coil elements can be chosen comparatively arbitrarily by varying the number of turns of the conductor. The conductor may be, for example a conductor track on an electrically insulating substrate, so that the coil elements can be manufactured by means of a method known, for example for printed circuit boards (PCBs). An even higher flexibility as regards the number of turns, and hence the value of the self-inductance, however, is achieved in a preferred embodiment which is characterized in that each of the coil elements is formed as a self-supporting, substantially saddle-shaped coil wound from an electrically conductive wire provided with an electrically insulating sheath.
In order to tune the RF coil to a given resonance frequency and to obtain the desired cosinusoidal current distribution, not only the self-inductances of the coil elements are required, but also capacitive elements. Therefore, a further preferred embodiment of the apparatus in accordance with the invention is characterized in that the coil elements are electrically connected in series, that each junction point between two successive coil elements in the series connection as well as the starting point and the end point of the series connection are connected to a common ground connection via a capacitive element, the starting point and the ground connection constituting a first and a second coil connection, respectively, and being electrically connected to respective connections of an RF transmitter and/or receiver device. For a given self-inductance of the coil elements, the resonance frequency can be adjusted by a suitable choice of the values of the impedances. A very simple version of this embodiment is characterized in that each of the capacitive elements is formed by a capacitor, the capacitances of the capacitors connected to the junction points being identical and twice as high as the capacitances of the capacitors connected to the starting point and the end point. Another very simple version is characterized in that each of the capacitive elements is formed by a capacitor, the capacitances of the capacitors being identical.
As has already been stated, the RF coil serves to generate and/or receive a substantially uniform magnetic field which is oriented perpendicularly to the cylinder axis. To this end, the current in the axial conductor elements is proportional to the cosine of an angle θ indicating the position of each axial conductor element on the circumference of the cylinder. The current through the end conductor elements, however, generates a magnetic field which is oriented approximately parallel to the axis of the cylinder. In order to minimize this disturbing magnetic field, a further preferred embodiment of the apparatus in accordance with the invention is characterized in that the coil elements are arranged around the cylinder axis in such a manner that loop conductor segments which belong to different coil elements, are situated at the same end of the cylinder, and are connected to the axial conductor elements which, considering the cosinusoidal current distribution, are arranged to carry the same or substantially the same currents, carry currents of opposite directions in the operating condition. As a result of the cosinusoidal current distribution, the axial conductor elements which carry the same or substantially the same currents in the operating condition are situated near one another on the cylinder circumference. The loop conductor segments connected to these axial conductor elements overlap one another over a part of the cylinder circumference and, evidently, the current intensities in these loop conductor segments are also equal or substantially equal. Because these current intensities are oppositely directed, the axially directed magnetic fields generated thereby will compensate one another, so that the ultimately remaining, axially directed disturbing magnetic field is minimized.
In the ideal case the current in the axial direction would have to be continuously sinusoidally distributed across the cylinder circumference. However, this would mean that the cylinder should have a substantially closed electrically conductive surface all around. It is difficult to construct such a surface and, moreover, a closed RF coil is very annoying to a patient to be examined. To this end, the cosinusoidal current distribution is approximated in practice by means of a finite number of axial conductor elements. A suitable approximation is achieved when the RF coil comprises at least four coil elements which are uniformly distributed across the circumference of the cylinder. The number of axial conductor elements then equals eight.
In many cases rotation of the transmitted and/or received RF magnetic field is desirable. In such cases a so-called quadrature coil system is often used, which system comprises two RF coils which generate and/or receive mutually perpendicularly directed RF magnetic fields which are excited and/or read out with a mutual phase difference of 90°. An embodiment of the apparatus in accordance with the invention which is suitable for this purpose is characterized in that the apparatus comprises a first and a second RF coil, the first and second RF coils essentially having the same construction and being concentrically arranged in such a manner that relative to the first coil connection of the first RF coil the first coil connection of the second RF coil has been rotated through an angle of 90° about the cylinder axis, and that the first coil connections of the first and the second RF coil are connected to respective connections of the RF transmitter and/or receiver device which are arranged to supply and/or receive RF signals with a mutual phase difference of 90° in order to enable mutually perpendicularly oriented RF magnetic fields with a phase difference of 90°to be generated and/or received. A further suitable embodiment is characterized in that the RF coil is composed of 2n electrically series-connected coil elements, n being an even, positive number, that the starting point of the series connection is electrically connected to the end point, that each junction point between two coil elements is connected, via a mainly capacitive element, to a common ground connection, that each time two coil elements having the sequence numbers i and n+i in the series connection are wound one over the other, where 1≦i≦n, that the RF coil comprises first, second and third coil connections which are formed by the starting point, the junction point between the coil elements having the sequence numbers n/2 and n/2+1, and the ground connection, respectively, and that the first and second coil connections are connected to respective connections of the RF transmitter and/or receiver device which are arranged to supply and/or receive RF signals with a mutual phase difference of 90° in order to enable mutually perpendicularly oriented RF magnetic fields with a phase difference of 90° to be generated and/or received.
BRIEF DESCRIPTION OF THE DRAWING
These and other aspects of the invention will be described in detail hereinafter with reference to the drawing, wherein:
FIG. 1 shows diagrammatically an embodiment of a magnetic resonance apparatus in accordance with the invention,
FIG. 2 is a perspective view of an embodiment of an RF coil for the device shown in FIG. 1,
FIG. 3 is a perspective view at an enlarged scale of a coil element of the RF coil shown in FIG. 2,
FIG. 4 is a diagrammatic axial view of an RF coil of the type shown in FIG. 2,
FIG. 5 shows an example of a circuit diagram of the RF coil shown in FIG. 2,
FIG. 6 is a diagrammatic axial view of a first embodiment of a quadrature coil system suitable for the apparatus shown in FIG. 1,
FIG. 7 shows a circuit diagram for the quadrature coil system shown in FIG. 6,
FIG. 8 shows a circuit diagram for a second embodiment of a quadrature coil system suitable for the apparatus shown in FIG. 1, and
FIG. 9 is a simplified representation of the circuit shown in FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The magnetic resonance apparatus which is diagrammatically shown in FIG. 1 comprises a first magnet system 1 for generating a steady magnetic field H, a second magnet system 3 for generating magnetic gradient fields, and first and second power supply sources 5 and 7 for the first magnet system 1 and the second magnet system 3, respectively. A radio frequency (RF) coil 9 serves to generate an RF magnetic alternating field; to this end, it is connected to an RF source 11. The RF coil 9 can also be used for detection of spin resonance signals generated by the RF transmitted field in an object to be examined (not shown); to this end, it is connected to a signal amplifier 13. The output of the signal amplifier 13 is connected to a detector circuit 15 which is connected to a central control device 17. The central control device 17 also controls a modulator 19 for the RF source 11, the second power supply source 7 and a monitor 21 for display. An RF oscillator 23 controls the modulator 19 as well as the detector 15 processing the measurement signals. For cooling, if any, of the magnet coils of the first magnet system 1 there is provided a cooling device 25 comprising cooling ducts 27. The RF coil 9, arranged within the magnet systems 1 and 3, encloses a measurement space 29 which is large enough to accommodate a patient to be examined, or a pan of the patient to be examined, for example the head and the neck, in an apparatus for medical diagnostic measurements. Thus, a steady magnetic field H, gradient fields selecting object slices, and a spatially uniform RF alternating field can be generated within the measurement space 29. The RF coil 9 can combine the functions of transmitter coil and measuring coil. Alternatively, different coils can be used for the two functions, for example measuring coils in the form of surface coils. Hereinafter, the RF coil 9 will usually be referred to only as the transmitter coil. For the use of the coil as a measuring coil the same considerations apply in accordance with the reciprocity theorem. If desired, the coil 9 may be enclosed by an RF field shielding Faraday cage 31.
FIG. 2 is a perspective view of the construction of an embodiment of the RF coil 9. The RF coil 9 is shaped mainly as a straight circular cylinder having a central axis 33 extending parallel to the direction of the steady magnetic field H in the operating condition (see FIG. 1). The RF coil 9 comprises a number of axial conductor elements 35 which extend parallel to the axis 33 and which are regularly distributed across the cylinder surface in such a manner that diametrically opposite each axial conductor element another axial conductor element extends. Two axial conductor elements 35 extending diametrically relative to the axis 33 together constitute a pair. Near the ends of the axial conductor elements 35 there are situated end conductor elements 37 which extend around the central axis 33 and which are composed of loop conductor segments 39. Each of the loop conductor segments 39 extends through an arc of 180° around the axis 33 and interconnects corresponding ends of a pair of axial conductor elements 35 situated diametrically relative to the axis. In conjunction with the two loop conductor segments interconnecting their ends, each pair of axial conductor elements 35 constitutes a coil element 41 which will be described in detail hereinafter with reference to FIG. 3.
FIG. 3 is a perspective view of a coil element 41 at a scale larger than that of FIG. 2. The present embodiment of the coil element 41 is formed as a self-supporting, substantially saddle-shaped coil wound from electrically conductive wire. The wire may be of a type commonly used for the winding of coils, for example single copper wire or litz wire provided with an electrically insulating lacquer or enamel layer. After winding, the shape of the coil element is stabilized, for example by impregnation or by heating of the lacquer layer. The free ends of the wire are fed out as connection conductors 43. The coil element 41 can also be wound on a coil former or be constructed as surface wiring on an electrically insulating substrate. The current directions in the axial conductor elements 35 of each coil element 41 are opposed as denoted by the arrows 44. Furthermore, the RF coil 9 is arranged so that the current distribution as a function of the position of the axial conductor elements 35 on the circumference of the cylinder is substantially cosinusoidal.
The connection conductors 43 of the various coil elements 41 constituting the RF coil 9 are connected, via capacitive elements 45, to a metal ring segment 49 (see FIG. 2) which is grounded at 47 and which constitutes a common ground connection. FIG. 2 shows only three capacitive elements 45 in order to keep the figure simple. In reality the number of capacitive elements will be larger as will be described with reference to the circuit diagram shown in FIG. 5. One of the connection conductors 43 is connected, via a connection cable 51, to the RF source 11 and/or the signal amplifier 13.
FIG. 4 is an end view in the axial direction of an RF coil 9 of the type described with reference to the FIGS. 2 and 3. The RF coil 9 comprises four coil elements 41 whose loop conductor segments 39 which are situated at one end are visible in FIG. 4. The associated axial conductor elements 35 are indicated in this figure, the current direction in each axial conductor element being indicated in a conventional manner: a dot means that at a given instant the current is directed towards the viewer and a cross means that the current is directed away from the viewer at that instant. As has already been stated, the current distribution is cosinusoidal. This means that the current intensity in an arbitrary axial conductor element 35 is proportional to cos θ at any instant, θ being the angle indicating the position of the relevant axial conductor element on the circumference of the cylinder relative to a zero position denoted by the arrow 53. In the example shown, the first axial conductor element 35 is situated in a position for which θ=22.5°; a next conductor element is provided every 45°. The absolute value of the current intensity in the axial conductor elements 35 for which cos θ has the same absolute value is the same. The associated current directions in the loop conductor segments 39 are denoted by arrows 55. The loop conductor segments 39 which are associated with different coil elements 41 and which are connected to axial conductor elements 35 for which cos θ has the same value carry the same current intensity. The coil elements 41 are arranged around the cylinder axis 33 in such a manner that, when situated at the same end of the cylinder, these loop conductor segments carry currents of opposite directions. Consequently, the magnetic fields produced by these currents and extending parallel to the cylinder axis 33 compensate one another over a part of the circumference of the end conductor element 37 formed by the loop conductor segments 39 (see FIG. 2). The areas in which such compensation takes place are denoted by dashed arcs 57 and 59 in FIG. 4. Outside these areas, however, the currents in the loop conductor segments 39 produce an axial magnetic field. However, it will be readily understood that these fields are oppositely directed for parts of the loop conductor segments 39 situated diametrically relative to the axis 33. As a result, they will substantially cancel one another at least in the vicinity of the axis 33.
FIG. 5 shows a circuit diagram of an RF coil of the type shown in FIG. 2. The four coil elements 41 are electrically connected in series and each junction point 61 between two successive coil elements in the series connection is connected, via one of the capacitive elements shown in FIG. 2, being a capacitor 63 in the present case, to a common ground connection 65 which is preferably formed by the ring segment 49 shown in FIG. 2. The starting point 67 and the end point 69 of the series connection are also connected to the ground connection 65 via a respective capacitor 71. The capacitances of said capacitors 63 are equal to an amount being twice the capacitances of the capacitors 71. The starting point 67 and the ground connection 65 constitute first and second coil connections, respectively. Each of these points is connected to one of the connections of the RF transmitter device 11 and/or the RF receiver device 13, represented in the diagram by a current source 73. The network thus formed behaves as a low-pass filter. It is essentially a "lumped element transmission line" having a length of one half wavelength, i.e. between the starting point 67 and the end point 69 the amplitude of the current through the axial conductor elements 35 varies according to the cosine of an angle proportional to the distance from the starting point. At the starting point 67 this angle has the value zero and at the end point 69 it equals 180°, corresponding to one half wavelength. Because each of the axial conductor elements 35 is connected, via the associated loop conductor segments 39, to a conductor element which is diametrically situated relative to the central axis 33, the desired cosinusoidal current distribution is thus achieved across the entire circumference of the RF coil 9. As a result, an RF coil constructed as a transmission line of one half wave length is suitable to generate a linearly polarized RF magnetic field. It is to be noted that a linearly polarized RF magnetic field can also be generated by an RF coil constructed as a transmission line having a length of a full wavelength. The circuit diagram of such a coil deviates from the diagram shown in FIG. 5 merely in that the number of coil elements (for an equally accurate approximation of the desired RF magnetic field) is twice as large and in that the capacitors 63 have the same value as the capacitors 71.
FIG. 6 is a diagrammatic end view in the axial direction of a combination of a first and a second RF coil as can be used in the apparatus shown in FIG. 1. The first RF coil 109 is concentrically enclosed by the second RF coil 209, so that the two RF coils have the same central axis 33. The first and second RF coils 109 and 209 essentially have the same construction as the previously described RF coil 9. The second RF coil 209, however, has a diameter which is so much larger than that of the first RF coil 109 that the two coils can be arranged one exactly in the other. The RF coils 109 and 209 are oriented in such a manner that the axial conductor elements 135 of the first RF coil are situated in the same angular positions on the cylinder surface as the axial conductor elements 235 of the second RF coil, be it that the first coil connection 267 of the second RF coil has been rotated through an angle of 90° about the cylinder axis 33 relative to the first coil connection 167 of the first RF coil. An equivalent combination of first and second RF coils 109 and 209 can be obtained by simultaneously winding correspondingly situated coil elements of the two RF coils by means of two separate conductors. In that case the first and second RF coils 109 and 209 will have substantially the same diameter.
FIG. 7 shows a circuit diagram of the combination of first and second RF coils 109 and 209 shown in FIG. 6. The diagram for the first RF coil 109 corresponds exactly to the diagram shown in FIG. 5 and corresponding elements are denoted by the corresponding reference numerals increased by 100. The diagram for the second RF coil 209 is composed in such a manner that coil elements 241 of the second RF coil and coil elements 141 of the first RF coil 109 which occupy the same positions on the cylinder surface are shown one directly above the other in the figure. Therefore, the first coil connection 267 of the second RF coil 209, rotated through 90° with respect to the first coil connection 167 of the first RF coil 109 as described above, is situated approximately midway the circuit diagram. For the remainder the diagram for the second RF coil 209 is also the same as the diagram shown in FIG. 5. Corresponding elements are denoted by corresponding reference numerals increased by 200.
The first coil connection 167 of the first RF coil 109 is connected to a first current source 173 and the first coil connection 267 of the second RF coil 209 is connected to a second current source 273. The first and second current sources 173 and 273 represent first and second connections of an RF transmitter and/or receiver device which are arranged to supply and/or receive RF signals with a mutual phase difference of 90°. The transmitter and receiver devices may be of the type indicated in FIG. 1 in which the output of the RF source 11, or the input of the signal amplifier 13, is connected to a hybrid network (not shown) which is known per se. The first and second RF coils 109 and 209 thus connected to an RF transmitter and/or receiver device together constitute a quadrature coil system which is capable of generating and/or receiving mutually perpendicularly oriented RF magnetic fields with a phase difference of 90°. A circularly polarized RF magnetic field can thus be generated.
FIG. 8 shows a circuit diagram of a second embodiment of a quadrature coil system suitable for use in the apparatus shown in FIG. 1, and FIG. 9 shows a simplified version of the same circuit diagram. The quadrature coil system of the present embodiment comprises an RF coil 309 which is constructed as a single, consecutively wound coil. The construction of the RF coil 309 in principle corresponds to the construction of the RF coil 9 shown in FIG. 2. However, the RF coil 309 is composed of eight electrically series-connected coil elements 341a, . . . 341h. Each time two coil elements are wound one on the other, the sequence numbers of said two coil elements differing each time by four in the series connection, for example the coil elements 341a and 341e. The coil elements wound onto one another are shown one on top of the other in FIG. 8. Because the interconnections are thus less clear in FIG. 8, for the sake of clarity FIG. 9 shows a simplified diagram in which the coil elements are consecutively shown in a conventional manner. The starting point 367 of the series connection is electrically connected to the end point 369 by way of a connection lead 381. Each junction point 361 between two successive coil elements 341a . . . 341h, including the junction point established by the connection lead between the first coil element 341a and the last coil element 341h, is connected to a common ground connection 365 via a capacitor 363. The values of all capacitors 363 are the same. The starting point 367 constitutes a first coil connection of the RF coil and the junction point between the coil elements 341b and 341c, denoted by the reference 383, constitutes a second coil connection. The ground connection 365 constitutes a third coil connection. The first and second coil connections 367 and 383 are connected to respective current sources 173 and 273 which represent, in the same way as in FIG. 7, first and second connections of an RF transmitter and/or receiver device which are arranged to supply and/or receive RF signals with a mutual phase difference of 90°. The RF coil 309 then acts as a combination of two independent coils which together generate a rotating RF magnetic field.
The RF coil 309 of the embodiment shown in the FIGS. 8 and 9 comprises eight coil elements 341a . . . 341h. Evidently, it is also possible to construct a quadrature coil system with an RF coil which is constructed in the same manner but comprises a different number of coil elements, provided that this number equals 2n, n being an arbitrary positive, even number. In that case each time two coil elements having the sequence numbers i and n+i in the series connection will be wound one over the other, where 1≦i≦n. The second coil connection 383 is then formed by the junction point between the coil elements having the sequence numbers n/2 and n/2+1. | The apparatus including a mainly cylindrical RF coil (9) having a central axis (33) which extends in its longitudinal direction, which coil has a number of axial conductor elements (35) which extend parallel to the central axis across a mainly cylindrical surface, and end conductor elements (37) which extend around the central axis near the ends of the axial conductor elements. The axial conductor elements (35) extend pair-wise diametrically relative to the central axis and the RF coil (9) is arranged to generate a substantially cosinusoidal current distribution as a function of the position of the axial conductor elements on the circumference of the cylinder in order to enable generation and/or reception of a substantially uniform RF magnetic field which is oriented perpendicularly to the cylinder axis. Each of the end conductor elements (37) consists of a number of loop conductor segments (39) which corresponds to the number of pairs of axial conductor elements (35). Each loop conductor element extends through an are of 180° about the central axis (33) and electrically interconnects corresponding ends of a pair of axial conductor elements which are diametrically situated relative to the central axis. In conjunction with the loop conductor segments (39) connected to their ends, each pair of axial conductor elements (35) constitutes a coil element (41) which is composed of a number of turns of an elongate electrical conductor. The designer has great freedom as regards the choice of the self-inductance of the coil elements (41), and hence as regards the choice of the resonance frequency of the RF coil (9). | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a process for producing a flexible printed base having a good heat resistance and a superior folding endurance.
2. Description of the Related Art
Flexible printed bases are used for producing printed circuits having flexibility, and in recent years, it has been more and more required to make the size of electronic equipment smaller, make the base thinner and make the density of the circuits higher.
Conventional polyimide flexible bases have been mainly produced by applying a polyimide film onto a copper foil by the medium of an adhesive. However, since such bases use an adhesive, problems have been raised in the aspect of heat resistance, electric characteristics, etc.; hence such bases have been impossible to sufficiently make use of the characteristics thereof.
In order to solve these problems, a process of subjecting a polyimide film to hot-melt adhesion onto a copper foil has been disclosed in Japanese patent application laid-open No. Sho 57-181,857/1982 and a process of directly coating a copper foil with a polyimide precursor, followed by heating and drying treatment (hereinafter referred to as "direct coating process") is disclosed in Japanese patent publication Nos. Sho 61-111,359/1986 application laid-open and Sho 63-69,634/1988.
As to these improvement processes, since no adhesive is used, the heat resistance, electric characteristics, etc. are improved, but since the former process employs steps of production of film, its hot-melt adhesion, etc., it requires the same number of steps or more as that of conventional products (using adhesives). Whereas, according to the direct coating process, since it has no step of film production, simplicity of steps is possible and also the heat resistance and electric characteristics of the resulting flexible printed base are superior, but the process cannot contribute to the high folding endurance of the base. Further, for use applications requiring a high folding endurance, rolled copper foil rather than electrolytic copper foil has often been used as copper foil. However, in general, rolled copper foil is not only more expensive than electrolytic copper foil, but also the peel strength of the resulting flexible printed base lowers.
The present invention proposes a process for producing a cheap flexible printed base having solved the above problem and having a superior folding endurance.
It has been disclosed that when a flexible printed base is heat-treated at 100° to 200° C., its folding endurance is generally improved by about 1.5 times (Japanese patent application laid-open Nos. Sho 54-110,466/1979 and Sho 53-17,764/1978), but when an electrolytic copper foil is used for the base, the folding endurance does not reach that of rolled copper foil and is insufficient.
Further, when the electrolytic copper foil was subjected to heat curing in the atmosphere at 200° to 450° C, the folding endurance lowered. Whereas, when the above heat curing was carried out in an inert gas having an oxygen concentration of 0.5% or lower, preferably 0.2% or lower and under a tension of 0.02 to 0.2 Kg/cm, it has been found surprisingly enough that the folding endurance of the resulting flexible printed base was improved up to a similar folding endurance to that of rolled copper foil.
This improvement in the folding endurance has been found from X-ray diffraction pattern of the copper foil to originate from inhibition of thermal cleavage reaction of high molecules in the above-mentioned atmosphere and at the same time the crystalline configuration of the copper foil.
The present inventors have made extensive research on the improvement in the folding endurance of the printed base obtained according to the above direct coating process, and as a result have found that the folding endurance is improved by optimizing the conditions of the atmosphere and tension at the time of curing and this fact is greatly related to the crystalline size of copper of copper foil and the selective orientability of the crystalline surface of copper of copper foil.
SUMMARY OF THE INVENTION
The present invention resides in a process for producing a flexible printed base by directly coating a copper foil with a polyimide precursor, followed by heating, drying, and curing which process comprises carrying out said curing in an inert gas under a tension of 0.02 to 0.2 Kg/cm and at 200° to 450° C.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The inert gas atmosphere referred to herein means an atmosphere formed by purging the inside of a drying furnace with an inert gas such as nitrogen gas, etc. under pressure. As the inert gas, nitrogen gas having an oxygen concentration of 0.5% or less, preferably 0.2% or less is preferred. Of course, it is also possible to use rare gases such as argon, etc. and an inert gas such as CO 2 gas.
The flexible printed base in the present invention may be prepared by directly applying a polyimide precursor having a thermal expansion coefficient to the same extent as that of copper onto a copper foil, followed by heating, drying and curing.
As the polyimide precursor applied onto a copper foil, a polymer having repetition units expressed by the following formula is exemplified: ##STR1## wherein R 1 represents a tetravalent aromatic group and R 2 represents a divalent aromatic hydrocarbon radical.
Examples of the aromatic tetracarboxylic acid dianhydride (R 1 ) used in the preparation of the above precursor are pyromellitic acid, 2,3,3',4'-tetracarboxydiphenyl, 3,3',4,4'-tetracarboxydiphenyl, 3,3',4,4'-tetracarboxybenzophenone, etc.
Further, concrete examples of aromatic diamine (R 2 ) are p,m-phenylenediamine, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ketone, 3,4'-diaminodiphenyl ketone, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 4,4,-diaminodiphenylmethane, 2,2'-bis(4-aminophenyl)propane, 1,4-di(4-aminophenyl)-phenyl ether, 1,3'-di(4-aminophenyl)phenyl ether, diaminosiloxanediamines expressed by the formula ##STR2## wherein R 3 represents an aliphatic hydrocarbon radical of 1 to 3 carbon atoms or an aromatic hydrocarbon radical of 6 to 9 carbon atoms, R 4 represents a divalent aliphatic hydrocarbon radical of 3 to 5 carbon atoms or a divalent aromatic hydrocarbon radical of 6 to 9 carbon atoms and (represents an integer of 3 to 150, etc.
Examples of the organic solvent used for preparing these polyimide precursors are polar organic solvents 0 such as N-methyl-2-pyrrolidone, N,N'-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, cresol, etc. and these may be used alone or in admixture. The reaction is carried out in the range of 0° to 80° C.
As to the process for forming a polyimide film on a copper foil in the present invention, firstly a solution containing 10 to 30% by weight of a polyimide precursor is coated on the surface of the copper foil by means of Comma-Coater, doctor knife or the like, followed by removing the solvent contained in the solution by heating to 100° to 200° C., and heat-curing the resulting material in an inert gas having an oxygen concentration of 0.5% or less, under a tension of 0.02 to 0.2 Kg/cm and at 200° to 450° C.
In the process of the present invention, it is important to optimize the atmosphere and tension at the step of heat-curing at 200° to 450° C.
Namely, according to X-ray diffraction, crystals of copper of copper foil heat-cured at 200° to 450° C in the atmosphere contain copper oxide having a different crystal lattice from that of copper and being heterogeneously coexistent with copper crystals, to reduce the folding endurance of the base.
Further, as the first element of the present invention, when heat-curing is carried out in an inert gas having an oxygen concentration of 0.5% or less, preferably 0.2% or less at a temperature of 200° to 450° C., the resulting copper foil exhibits the same lattice constant as that of untreated copper foil and the crystal size increases uniformly to about three times the original size. Under a tension exceeding 0.2 Kg/cm, the resulting copper foil is elongated to raise a problem of causing anisotropies in MD (machine direction) and TD (transverse direction).
The present invention will be described in more detail by way of Examples and Comparative examples, but it should not be construed to be limited thereto.
PREPARATION EXAMPLE
Into a 10 l capacity glass reactor fixed with a thermometer, a stirrer and a nitrogen gas-introducing tube were introduced p-phenylenediamine (240.8 g), 4,4'-diaminodiphenyl ether (111.4 g) and N-methyl-2-pyrrolidone (7 l) in nitrogen gas current, followed by stirring these and dissolving together, gradually adding to the resulting solution, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride (818.9 g) with stirring, and reacting these at 20° C or lower for 5 hours to obtain a polyamic acid solution of a polyimide precursor.
The resulting polyimide precursor had a logarithmic viscosity of 1.8 as measured in N'-methyl-2-pyrrolidone at a concentration of the precursor of 0.5 g/dl at 30° C.
EXAMPLE 1
The polyimide precursor solution prepared above was coated onto one roughened surface of the two surfaces of an electrolytic copper foil of 18μ thick so as to give a coated thickness of 400 μm by means of a coater, followed by drying the copper foil having the polyimide precursor coated thereon in a hot-air drying furnace at 100° C. and 200° C., each for 10 minutes to remove the solvent contained in the solution and curing the resulting material in nitrogen gas containing an oxygen concentration of 0.3%, under a tension of 0.1 Kg/cm and at 250° C. and 350° C., each for 10 minutes to obtain a flexible printed base of the polyimide of 25μ.
This flexible printed base exhibited a folding endurance (MIT) of TD 57,000 times and MD 56,000 times. The measurement of MIT was carried out by forming a conductor of one reciprocation at a width of 1.5 mm and an interval between circuits of 1.0 mm by etching, flexing the conductor at a curvature radius of 0.8 mm, a flex rate of 180 times/min. and a strength of 500 gf/cm 2 and seeking the flex times at which complete disconnection of the conductor circuit occurred (JIS-C-P8115).
EXAMPLE 2
Example 1 was repeated except that an electrolytic copper foil of 35μ thick was used as copper foil to obtain a flexible printed base. The base exhibited a folding endurance of TD 800 times and MD 790 times. When the results are compared with those of Comparative example 5 (using a commercially available product), the folding endurance is superior.
COMPARATIVE EXAMPLE 1
Example 1 was repeated except that heat curing was carried out in the atmosphere, to obtain a flexible printed base. This base was considerably oxidized and exhibited a folding endurance of TD 2,800 times and MD 3,300 times.
COMPARATIVE EXAMPLE 2
Example 1 was repeated except that a copper foil of rolled copper of 18μ was used, to obtain a flexible printed base. This base exhibited a folding endurance of TD 42,000 times and MD 60,000 times.
COMPARATIVE EXAMPLE 3
Example 1 was repeated except that heat curing was carried out under no tension, to obtain a flexible printed base. This base exhibited a folding endurance of TD 35,000 times and MD 32,000 times.
COMPARATIVE EXAMPLE 4
Example 1 was repeated except that heat curing was carried out under a tension of 0.5 Kg/cm, to obtain a flexible printed base. This base exhibited TD 51,000 times and MD 35,000 times. Further, longitudinal wrinkles were formed on the base so that the printed base raised a problem in the aspect of processing step and could not be used.
COMPARATIVE EXAMPLE 5
A commercially available flexible printed base (electrolytic copper product) obtained by conventional lamination with an adhesive was subjected to measurement of its folding endurance in the same manner as in Example 1, to exhibit TD 288 times and MD 330 times.
As described in detail, according to the process of the present invention, when a flexible printed base is produced according to a direct coating process of directly coating a polyimide precursor onto a copper foil, followed by heat curing at a high temperature, it has become possible to produce a flexible printed base having a far superior folding endurance. | In a process for producing a flexible printed base by directly coating a copper foil with a polyimide precursor, followed by heating, drying and curing, a process affording a flexible printed base having a superior folding endurance and a good heat resistance at a cheap cost is provided, which process comprises carrying out the curing in an inert gas under a tension of 0.02 to 0.2 Kg/cm and at 200° and 450° C. | 8 |
The present invention relates to cooktops in general and to cooktops with grills in particular. The invention further relates to cooktops with grills incorporating a downdraft feature using a fan to remove grease laden air from the cooking environment and, more particularly, to the method and apparatus for requiring high speed downdraft fan operation during grilling operations.
BACKGROUND OF THE INVENTION
Conventional cooktops are known to include a grill portion and a range top portion. Typically, the cooktop can include gas or electric burners and a grill element, along with associated controls. Some cooktops further include a downdraft feature whereby a downdraft fan pulls cooking odors and grease laden air downwardly through a grate in the cooktop and moves it, through ducting, from the kitchen to outside the home.
Typically the downdraft fans are multiple speed fans, having a low speed and a high speed. The fans are generally controlled by a multi-position switch or a potentiometer or rheostat to set the speed of the fan. For removal of normal cooking odors or steam or the like, low speed operation of the downdraft fan is typically adequate. However, when using the grill portion, a fan set at low speed has been unable to withdraw all of the grease laden air from the kitchen and duct it to the outside environment. In particular, experience has shown that a downdraft fan must move about 300 cubic feet of air per minute (cfm) in order to avoid grease accumulation in the ducting. At slower speeds, grease can accumulate, especially at elbows formed in the ducting. Eventually, the grease accumulation can begin to close off and restrict the air flow through the ducting, thereby reducing the effectiveness of the air removal fans, and cause other problems as well. Unfortunately, a cook can forget to set the fan at high speed. In some cases, the cook may intentionally operate the fan at low speed during grill operation, such as when a lower noise level may be desirable. Accordingly, it is desirable that a downdraft fan is always operated at high speed during grill operation regardless of the cook's selected operation of the fan.
SUMMARY OF THE INVENTION
The present invention automatically overrides the fan control switch and operates the fan at high speed whenever the grill portion is being used. In the invention, a downdraft cooktop includes an electrical switch having a plurality of cooking rate selections, a vapor withdrawal opening formed in the cooktop adjacent the grill element, a vapor withdrawal duct below and in communication with the withdrawal opening and with a withdrawal fan, an electric motor for driving the withdrawal fan, and a fan control switch for varying rates of operation of the fan. The withdrawal fan is operable for downdraft withdrawal of cooking vapors resulting from operation of the grill element. The invention further includes means for sensing the selection of grill operations and for bypassing the fan control switch and operating the electrical fan motor at a high rate for vapor withdrawal during grill operations.
The invention also includes an improved method of withdrawing cooking vapor from adjacent a cooktop in which a grill is operated. The cooking vapor is withdrawn downwardly from adjacent the cooktop by a motor-driven fan operable at high and low rates of withdrawal selected by a multi-position electrical control switch. The improvement to the method comprises sensing the selection of the grill for cooking operation, and bypassing the electrical control switch and connecting the motor driven fan for operation at only a high rate of withdrawal of cooking vapors. According to one aspect of the invention, upon sensing the de-selection of the grill, the electrical switch is not bypassed. In preferred methods, the grill comprises an electrical grill element, and the presence of the grill element is sensed.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of a preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.
BRIEF DESCRIPTION OF THE INVENTION
FIG. 1 is a plan view of the cooktop having left and right bays and a center panel with a grill element positioned in the right bay and having a grill heating element covered by a partially broken away grill grate;
FIG. 2 is a side section view taken along lines 2--2 of FIG. 1;
FIG. 3 is a plan view of a grill heating element for use with the grill element shown in FIG. 2;
FIG. 4 is a side view of the grill heating element of FIG. 3;
FIG. 5 is a shunt for use with the grill heating element of FIGS. 3 and 4; and
FIG. 6 is a schematic of the circuitry for controlling the fan speed in a cooktop.
DETAILED DESCRIPTION OF THE INVENTION
A cooktop 10 for use with the present invention is illustrated in FIGS. 1 and 2. The cooktop 10 includes a burner box assembly 12 divided into a right bay 14, a left bay 16 and a center section 18 positioned therebetween. The right and left bays 14, 16 are formed to retain and support modular cooking elements 20, such as a grill element 22, shown partially broken away in the right bay 14 of FIG. 1, or a burner assembly (not shown). Each bay 14, 16 also includes a conventional female ceramic block connector 24 for electrically connecting the cooking elements 20 to the cooktop 10. The cooking elements 20, such as grill element 22, as shown in FIGS. 3 and 4, include a conventional male ceramic block connector 26 having a plurality of connector blades 28 for engaging receiving apertures in the female block connector 24 and a center locating/grounding pin 30 for aligning the male block connector 26 with the female block connector 24. The connector blocks engage in a fashion similar to a conventional electrical plug and wall outlet in a home.
The grill element 22 includes a grill heating element 23. A metal shunt 32, shown in FIG. 5, is installed between two adjacent connector blades 28 of the grill heating element 23. The shunt 32 is a single piece of metal, such as steel, bent to form a generally U-shaped piece having a base portion 31 and a pair of legs 33 extending perpendicular to the base portion 31. The base portion 31 extends between the adjacent connector blades 28 so as to position the legs 33 in contact with the adjacent connector blades 28, thereby providing an electrical short-circuit between the adjacent connector blades 28.
The center section 18 includes a control panel 34, with various cooking controls 36, and a withdrawal opening 38. The withdrawal opening 38 is connected to an air passage 42 which includes a filter 44 for filtering particulate matter from air drawn through the withdrawal opening 38. The air passage 42 is connected to a blower scroll 46, which in turn is connected to duct work 48 leading away from the blower scroll 46. A withdrawal fan 50 is mounted to the plenum 46 so as to draw air into the plenum 46 through the withdrawal opening 38, air passage 42 and filter 44, and move the air out of the kitchen through the duct work 48.
When the grill heating element 23 is being installed in one of the bays 14, 16 of the burner box assembly 12, the center locating/grounding pin 30 and the connector blades 28, with the shunt 32, are aligned with corresponding receiving apertures in the female block connector 24. As the grill heating element 23 is pushed into position in the bay 14, 16, the locating/grounding pin 30 and connector blades 28 fully engage the female block connector 24, providing electrical connection to the grill heating element 23.
FIG. 6 shows a schematic diagram for the electrical circuit 60 of a dual bay cooktop 10, such as shown in FIGS. 1 and 2. It will be appreciated that the circuit 60 can be readily adapted to serve any number of bays. The circuit 60 includes control switches 62a-62d for controlling the heating elements 63a-63b and positions for a plurality of shunts such as the left grill element shunt position 64 and the right grill element shunt position 66.
In operation, 120 VAC is continuously supplied from L1 to a switch 69a that is movable between a normally-closed position and an open position, and a switch 69b that is movable from a normally-open position to a closed position. In the normally-closed position, the L1 120 VAC is applied through the switch 69a to an input terminal of a fan control switch 70. Moving the fan control switch 70 from the off position to the low speed or high speed position sends L1 120 VAC to the low speed or high speed windings, respectively, of the fan motor 72. The fan control switch 70 is illustratively a three position switch, but it will be appreciated that other switching devices can be used instead.
For purposes of the following discussion, it is assumed that a grill element 22 is installed in the right bay 14 and a burner assembly (not shown) is installed in the left bay 16. In this configuration, a shunt 32 is located at the right grill element shunt position 66, but no shunt is present at the left grill element shunt position 64.
When either of the right side control switches 62c, 62d is switched on, the shunt 32 located at the right grill element shunt position 66 sends 120 VAC from L1, L2 to the coil 68a of the fan relay 68 which moves switch 69a from its normally-closed position to its open position, and moves switch 69b from its normally-open position to its closed position. Moving the switch 69a to the open position disconnects the fan switch 70 from line L1, and moving the switch 69b to its closed position connects the L1 120 VAC signal directly to the high speed terminal of the fan switch 70, effectively bypassing the fan switch 70. Thus, if the grill element 22 is installed in the cooktop 10 and either of the control switches 62c, 62d is on, the fan motor 72 is automatically operated at full speed. Moreover, by moving the switch 69a from the normally closed position, L1 120 VAC is removed from the input to the fan switch 70, thereby disabling the fan control switch 70 from energizing the motor windings. Thus, in the FIG. 6 configuration, relay coil 68b senses selection of operation of a grill unit 23 by control switches 62c, 62d through shunt 32 at the grill element shunt position 64, which provides a means for sensing the presence of a grill element in the cooktop, and the switches 69a, 69b of relay 68 automatically select high speed operation of the downdraft withdrawal fan 72 and bypass the fan control switch 70.
If a left side control switch 62a, 62b is switched on, the fan relay coil 68a remains electrically isolated by the absence of a shunt 32 at grill element shunt position 64. In normal operations, a burner assembly would not include a shunt 32, and the left side grill element shunt position 64 is an open circuit. Thus, in the configuration illustrated in FIG. 6, the L1 120 VAC continues to be supplied to the input terminal of the fan switch 70 through the contact 69a, which remains in the normally-closed position, when only control switches 62a and 62b are operated.
An indicator light 76 is included to provide an indication to a cook that at least one of the control switches 62 is in the on position. When any of the control switches 62a-62d is switched on, L1 120 VAC is applied to the indicator light 76 via connection junctions 80a, 80b.
Although the invention has been described in detail with reference to a particular preferred embodiment, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims. | A downdraft cooktop includes an electrical switch having a plurality of cooking rate selections, a vapor withdrawal opening formed in the cooktop adjacent a grill element, a vapor withdrawal duct below and in communication with the withdrawal opening and with a withdrawal fan, an electric motor for driving the withdrawal fan, and a fan control switch for varying rates of operation of the fan. The withdrawal fan is operable for downdraft withdrawal of cooking vapors resulting from operation of the grill element. Grill operation is sensed and during grill operation, the fan control switch is bypassed and the electrical fan motor is operated at a high rate for vapor withdrawal. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a 371 U.S. National Stage of International Application No. PCT/JP2013/065475, filed on Jun. 4, 2013, which claims the benefit of priority from Japanese Patent Application No. 2012-210755, filed on Sep. 25, 2012. The disclosures of the above applications are incorporated herein by reference.
TECHNICAL FIELD
The present invention relates to distortion compensation to reduce a distortion component produced by a transmission device which transmits radio waves which are power-amplified by a high-frequency power amplifier.
BACKGROUND ART
The orthogonal frequency division multiplexing (OFDM) modulation method (hereinafter referred to as OFDM method) and the quardrature amplitude modulation method (hereinafter referred to as QAM method) are adopted in the terrestrial digital broadcasting and the multimedia broadcasting. The modulation signal in the terrestrial digital broadcasting and the multimedia broadcasting is constructed by constituent unit periods and has average power and peak power of a signal which are considerably different.
When the linearity is ensured by supplying a power amplifier with such a fixed voltage as to be able to produce peak power in a power amplification system, the time that the peak power is produced is extremely short and as a result the power supply efficiency of the amplifier is reduced. As a technique for solving this problem, there is known an envelope tracking method power amplification system (EER) as described in a patent literature 4. When a power supply voltage of an amplifier is changed, the characteristics of the amplifier are also changed. When a class AB push-pull amplifier is adopted in order to improve the efficiency, the characteristics of the amplifier are also varied at small amplification and peak.
By the way, an MOS-FET makes conduction only by applying a voltage between a source and a gate thereof and accordingly a transient response thereof in the direction of turning-on is fast, although since the MOS-FET continues to be conductive until electrical charges are removed from the gate thereof, a transient response in the direction of turning-off is slow. Hence, asymmetrical distortion is made large in an up-and-down direction of waveform on a time axis and even in an up-and-down direction on a frequency axis. Moreover, the MOS-FET has a conductive resistance varied in temperature. Further, in an MOS-FET made of GaN, electrons are trapped in a gate electrode in proportion to an accumulation amount of an electric field on a gate by a voltage on a drain electrode, so that a conductive resistance thereof is deteriorated (refer to a non-patent literature 7). These variation and deterioration are named historical distortion or memory distortion generically.
As a conventional technique of pre-compensation of nonlinear distortion, specifically as an example of a technique of independent compensation of odd order distortion, the patent literature 1 may be referred to.
A high-frequency power amplifier has so-called remarkable memory effect in which a past signal is generally influenced with extension to a wide band of signal and distortion is increased, so that hysteretic characteristic and even symmetrical distortion are increased. Thus, a circuit scale for the pre-compensation of distortion is enlarged. Accordingly, a method of reducing the circuit scale of the pre-compensation of distortion by the memory effect of the high-frequency power amplifier is proposed in a non-patent literature 1.
A patent literature 2 discloses a pre-compensation technique of distortion using time difference of the even order.
A patent literature 3 discloses a pre-compensation technique of distortion using differentiation of amplitude and phase.
However, the techniques for compensating the even order distortion by the differentiation of amplitude and phase in the patent literatures 2 and 3 have a drawback that convergence of the pre-compensation for reducing the even order distortion of the memory effect requires time even if the even order distortion of the memory effect is changed.
Furthermore, a Cartesian loop transmitter feeds back an output signal of an amplifier to a baseband part and compares signals before and behind amplification with each other to make detection and correction of error, so that the linearity of the transmitter can be increased. However, input/output and wiring of a chip are contained in a path for the feedback and accordingly transmission of signals is delayed for that. Influence of this delay is increased in proportion to frequency and accordingly there arises a problem that the stability is deteriorated when the band is widened. Accordingly, this time, a route which does not pass through a frequency converter is added in addition to the feedback path in the prior art and only a high-frequency component which influences the stability passes through the route to thereby reduce the influence of delay (refer to non-patent literature 6). In the non-patent literature 6, a complicated analog feedback path is added, so that it is difficult to make application to large-power amplification.
Accordingly, in the wide-band OFDM, it is difficult to improve the efficiency by combining the EER as described in patent literature 4 in which a power supply voltage of an amplifier is varied to change even characteristics of the amplifier with the pre-compensation technique of distortion as described in patent literatures 1 to 5 in which the convergence requires time.
Hence, as described in the patent literature 5, RF input and RF feedback are subjected to FFT and distortion coefficients of AM/PM conversion distortion, spectral re-growth distortion and memory effect distortion are calculated. The technique that RF input power and distortion coefficients are used to compensate I/Q input subjected to orthogonal demodulation of RF linearly and orthogonally modulate the input to be amplified is put to practical use in the terrestrial digital broadcasting.
Further, in non-patent literature 8, a terrestrial digital broadcasting transmitter manufactured as a product is described in which IM=−30 dB is realized in Doherty amplification of a carrier amplifier, a peak amplifier and a combined circuit, IM=−41 dB is realized in the distortion compensation and a complicated nonlinear filter is used to add historical (memory) distortion compensation and realize such low distortion and high efficiency as IM=−53 dB and power efficiency 27%.
CITATION LIST
Patent Literature
Patent Literature 1: WO2004/045067
Patent Literature 2: JP-A-2005-101908
Patent Literature 3: JP-A-2008-294518
Patent Literature 4: JP-A-2011-049754
Patent Literature 5: US 2011/0032033
Non-Patent Literature
Non-Patent Literature 1: Naoki Hongo, Tetuhiko Miyatani, Youichi Okubo and Yosihiko Akaiwa, “Digital Pre-Distorter for Power Amplifier having Memory Effect”, Electronic Information Communication Society Paper, Vol. J88-B, No. 10, pp. 2062-2071, 2005/10/01
Non-Patent Literature 2: Analog Devices, Orthogonal Compensation ADC, AD9269
Non-Patent Literature 3: Analog Devices, 500 Msps ADC, AD9434 Non-Patent Literature 4: Texas Instruments, 800 Msps Orthogonal Compensation DAC, DAC5688
Non-Patent Literature 5: Free Scale, 470-860 MHz, DVB-T (8 k OFDM 8 MHz), 125 W MOS-FET, MRFEVP8600H
Non-Patent Literature 6: Toshiba, Presentation of Report, http://www.toshiba.co.jp/rdc/rd/detail j/1002 02.htm
Non-Patent Literature 7: Nikkei Electronics, 2011 08.22, p. 67-p. 76 (p. 74)
Non-Patent Literature 8: Toshiba, Technical Report on Image Information Media Society, ITE Technical Report Vol. 36, No. 10RCT2012-47 (February 2012)
SUMMARY OF INVENTION
Technical Problem
According to the present invention, in the technique of the patent literatures 2 and 3 in which the even order distortion of the memory effect produced by the high-frequency power amplifier is compensated by means of differentiation of amplitude and phase, the long Cartesian loop transmission delay that is the total of the delay by orthogonal modulation of baseband, D/A, frequency conversion and filter and the delay by frequency conversion, filter, A/D and orthogonal demodulation in feedback exists in the signal transmission in which the output signal of the amplifier is fed back to the baseband part by the Cartesian loop and signals before and behind amplification are compared with each other to make detection and correction of error and accordingly it takes time to make convergence of the pre-compensation of distortion for reducing the even order distortion of the memory effect since the Cartesian loop transmission delay is longer than the time constant of the memory effect due to the OFDM characteristics having low average power and large peak power even if the even order distortion of the memory effect is changed.
Furthermore, since the Cartesian loop transmission delay is longer than the time constant for varying the power supply voltage of the high-frequency power amplifier with the orthogonal modulation OFDM input signal, it requires time to converge the pre-compensation of distortion.
Moreover, since the Cartesian loop transmission delay is longer than class AB peak variation time constant, it takes time to converge the pre-compensation of distortion.
Accordingly, the Doherty amplification of the carrier amplifier, the peak amplifier and the combined circuit is eliminated and a power supply voltage is made to follow an envelope using push-pull amplification, so that high efficiency is realized as compared with the Doherty amplification. Concretely, it is an object to make shortening of the Cartesian loop transmission delay, convergence in a short time and improvement of efficiency by making the pre-compensation distortion follow the envelope so that the power supply voltage follows the envelope in the push-pull amplification.
Solution to Problem
According to the present invention, in order to achieve the above object, a distortion compensation circuit which compensates distortion of a high-frequency power amplifier which power-amplifies an OFDM input signal having a frequency converted in a high-frequency band or an OFDM input signal in a high-frequency band, comprises an odd symmetrical distortion compensation signal generation circuit to independently generate an odd symmetrical distortion compensation coefficient signal of each order of the high-frequency power amplifier from a high-frequency signal or a high-frequency IF signal or a high-frequency OFDM input signal which is an input signal in a high-frequency band (hereinafter referred to as a high-frequency OFDM input signal) obtained by subjecting an OFDM signal to orthogonal modulation and digital-up conversion, an odd symmetrical distortion compensation signal addition circuit to prepare an error odd symmetrical distortion compensation signal from error of the high-frequency OFDM input signal, an output of the high-frequency power amplifier and an odd symmetrical distortion compensation coring signal obtained by coring the generated odd symmetrical distortion compensation coefficient signal of each order and add an odd symmetrical distortion compensation signal obtained by adding the error odd symmetrical distortion compensation signal and the odd symmetrical distortion compensation coefficient signal to the high-frequency OFDM input signal, an even symmetrical distortion compensation signal generation circuit to independently generate an even symmetrical distortion compensation coefficient signal of each order of the high-frequency power amplifier from the high-frequency OFDM input signal, and an even symmetrical distortion compensation signal addition circuit to prepare an error even symmetrical distortion compensation signal (following envelope) from error of the high-frequency OFDM input signal, the output of the high-frequency power amplifier and an even symmetrical distortion compensation coring signal obtained by coring the generated even symmetrical distortion compensation coefficient signal of each order and add an even symmetrical distortion compensation signal obtained by adding the error even symmetrical distortion compensation signal and the even symmetrical distortion compensation coefficient signal to the high-frequency OFDM input signal, whereby odd symmetrical distortion and even symmetrical distortion are compensated independently.
Furthermore, a distortion compensation circuit which compensates distortion of a high-frequency power amplifier which power-amplifies an OFDM input signal having a frequency converted in a high-frequency band, comprises an odd symmetrical distortion compensation signal generation circuit to independently generate odd symmetrical distortion compensation coefficient signal of each order of the high-frequency power amplifier from an OFDM input signal (hereinafter referred to as an orthogonal modulation OFDM input signal) obtained by subjecting an OFDM signal to orthogonal modulation, an odd symmetrical distortion compensation signal addition circuit to prepare an error odd symmetrical distortion compensation signal from error of the orthogonal modulation OFDM input signal, an output of the high-frequency power amplifier and an odd symmetrical distortion compensation coring signal obtained by coring the generated odd symmetrical distortion compensation coefficient signal of each order and add an odd symmetrical distortion compensation signal obtained by adding the error odd symmetrical distortion compensation signal and the odd symmetrical distortion compensation coefficient signal to the orthogonal modulation OFDM input signal, an even symmetrical distortion compensation signal generation circuit to independently generate an even symmetrical distortion compensation coefficient signal of each order of the high-frequency power amplifier from the orthogonal modulation OFDM input signal, and an even symmetrical distortion compensation signal addition circuit to prepare an error even symmetrical distortion compensation signal (following envelope) from error of the orthogonal modulation OFDM input signal, the output of the high-frequency power amplifier and an even symmetrical distortion compensation coring signal obtained by coring the generated even symmetrical distortion compensation coefficient signal of each order and add an even symmetrical distortion compensation signal obtained by adding the error even symmetrical distortion compensation signal and the even symmetrical distortion compensation coefficient signal to the orthogonal modulation OFDM input signal, whereby odd symmetrical distortion and even symmetrical distortion are compensated independently.
Further, a transmitter uses the distortion compensation circuit and a high-frequency power amplifier of envelope tracking method power amplification system (EER) for varying a power supply voltage of the high-frequency power amplifier with an orthogonal modulation OFDM input signal.
Moreover, the transmitter includes a delay unit of a time constant for varying the power supply voltage of the high-frequency power amplifier with the orthogonal modulation OFDM input signal, the delay unit being inserted in a previous stage of the distortion compensation circuit.
Advantageous Effects of Invention
As described above, according to the present invention, the Cartesian loop transmission delay can be made shorter than the time constant of the memory effect and the even order distortion of the memory effect produced by the power amplifier can be compensated to converge the compensation in a short time.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1A is a block diagram schematically illustrating a transmitter according to an embodiment of the present invention (which includes digital frequency conversion, high-frequency band ADC and high-frequency DAC as means for making compensation after orthogonal modulation and does not include orthogonal modulation, orthogonal demodulation and an averaging circuit in a Cartesian loop);
FIG. 1B is a block diagram schematically illustrating a transmitter according to an embodiment of the present invention (which includes orthogonal compensation ADC and orthogonal compensation DAC as means for making compensation after orthogonal modulation and does not include orthogonal modulation, orthogonal demodulation and an averaging circuit in the Cartesian loop);
FIG. 2 is a block diagram schematically illustrating an odd symmetrical distortion signal generation circuit of the embodiment of the present invention (automatic calculation of coefficient);
FIG. 3 is a block diagram schematically illustrating an even symmetrical distortion signal generation circuit of the embodiment of the present invention (automatic calculation of coefficient);
FIG. 4A is a schematic diagram illustrating (Cartesian) loop time constant (delay) of distortion compensation, ERR (power supply voltage variation) time constant (delay) and OFDM baseband input signal having orthogonal modulation, orthogonal demodulation and averaging circuits in Cartesian loop and time constant of memory effect distortion of a high-frequency power amplifier;
FIG. 4B is a schematic diagram illustrating loop time constant of distortion compensation and envelopes of OFDM high-frequency input signal and OFDM high-frequency output signal having no orthogonal modulation, orthogonal demodulation and averaging circuit in Cartesian loop and time constant (delay) of the memory effect distortion of the high-frequency power amplifier and envelope detection tracking (ERR) power supply voltage (approximating to baseband input signal) of a high-frequency output signal of the high-frequency power amplifier ((a) shows envelope detection tracking (ERR) power supply voltage (approximating to baseband input signal) of the high-frequency output signal of the high-frequency amplifier and (b) shows envelopes of OFDM high-frequency input signal and OFDM high-frequency output signal);
FIG. 5A is a schematic diagram illustrating envelopes of OFDM high-frequency input signal and coring threshold lines;
FIG. 5B is a schematic diagram illustrating envelope of the OFDM high-frequency input signal subjected to coring; and
FIG. 6 is a block diagram schematically illustrating a transmitter including orthogonal modulation, orthogonal demodulation and averaging circuits in the Cartesian loop.
DESCRIPTION OF EMBODIMENTS
The present invention is now described. First, distortion is described.
In the technique of subjecting even order distortion to amplitude differentiation and phase differentiation compensation in the patent literatures 2 and 3, as shown in FIG. 6 of a block diagram schematically illustrating a transmitter including orthogonal modulation, orthogonal demodulation and averaging circuits in a Cartesian loop, a long Cartesian loop (transmission) delay which is the total of a delay generated by passing through orthogonal modulation, D/A, frequency conversion and a filter of baseband and a delay generated by passing through frequency conversion, filter, A/D and orthogonal demodulation in a feedback path exists in the signal transmission in which an output signal of an amplifier is fed back to a baseband part in the Cartesian loop and signals before and behind amplification are compared to make detection and correction of error. Accordingly, as shown in FIG. 4A schematically illustrating a time constant of memory effect distortion of a high-frequency power amplifier, a time constant of the Cartesian loop of distortion compensation including orthogonal modulation, orthogonal demodulation and averaging circuits in the Cartesian loop and an OFDM baseband input signal, the delay in the Cartesian loop (transmission) is longer than the time constant (delay) of memory effect, the time constant (delay) of the (Cartesian) loop and the time constant (delay) of ERR (power supply voltage variation) even if even order distortion of the memory effect is changed due to characteristics of OFDM having small average power and large peak power. Furthermore, the delay in the Cartesian loop (transmission) is long and accordingly it takes time to make convergence of pre-compensation for reducing the even order distortion of the memory effect.
Moreover, the delay in the Cartesian loop (transmission) is longer than the time constant of the envelope detection tracking ERR of a high-frequency output signal for varying a power supply voltage of the high-frequency power amplifier with the orthogonal modulation OFDM input signal. Further, since the delay in the Cartesian loop (transmission) is long, convergence of pre-compensation requires time.
In addition, the delay in the Cartesian loop (transmission) is longer than the class AB peak variation time constant not shown and accordingly it takes time to make convergence of the pre-compensation.
Accordingly, the distortion reduction amount cannot be increased.
Hence, the delay in the Cartesian loop (transmission) is made shorter than the time constant of the memory effect. Further, the delay is made shorter than the time constant for varying the power supply voltage of the high-frequency power amplifier with the orthogonal modulation OFDM input signal. The delay is made shorter than the class AB peak variation time constant.
Furthermore, since the orthogonal modulation, the orthogonal demodulation and the averaging circuit are not provided in the Cartesian loop by providing digital frequency conversion, high-frequency band ADC and high-frequency band DAC or by providing orthogonal compensation ADC and orthogonal compensation DAC in compensation after orthogonal modulation as means for making compensation after orthogonal modulation of this method, symmetrical distortion and asymmetrical distortion can be detected independently and the delay in the Cartesian loop (transmission) for making compensation independently can be made short as shown in FIG. 4B schematically illustrating the envelope detection tracking (ERR) power supply voltage (approximating to the baseband input signal) of the high-frequency output signal of the high-frequency power amplifier, a time constant of memory effect distortion of the high-frequency power amplifier, a time constant of distortion compensation loop in which the orthogonal modulation, the orthogonal demodulation and the averaging circuit are not provided in the Cartesian loop and envelopes of the OFDM high-frequency input signal and the OFDM high-frequency output signal, so that convergence is made in a short time.
Accordingly, the distortion reduction amount can be increased.
Embodiment 1
Configuration and operation of an embodiment of the present invention are now described referring to FIG. 1A schematically illustrating in a block diagram a transmitter of the embodiment of the present invention (digital frequency conversion of a digital up converter and a digital down converter, a high-frequency band ADC and a high-frequency band DAC for making compensation after orthogonal modulation), FIG. 2 illustrating in a block diagram an odd symmetrical distortion signal generation circuit in the embodiment of the present invention, FIG. 3 illustrating in a block diagram an even symmetrical distortion signal generation circuit in the embodiment of the present invention, FIG. 4A schematically illustrating a time constant of the memory effect distortion of a high-frequency power amplifier, a time constant of a Cartesian loop of distortion compensation in comparison of baseband input signals and an OFDM baseband input signal, FIG. 4B schematically illustrating envelope detection tracking (ERR) power supply voltage (approximating to the baseband input signal) of the high-frequency output signal of the high-frequency power amplifier, the time constant of memory effect distortion of the high-frequency power amplifier, the time constant of distortion compensation loop in comparison of input signals at high frequency and envelopes of an OFDM high-frequency input signal and an OFDM high-frequency output signal, FIG. 5A schematically illustrating envelopes of the OFDM high-frequency input signal and coring threshold lines and FIG. 5B schematically illustrating envelope of the OFDM high-frequency input signal subjected to coring.
In the embodiment 1, difference (approximating to differentiation) between an input signal before sampling and the sampled input signal is calculated and coefficient and the input signal are subjected to complex multiplication to approximate a differentiation component of amplitude of the memory effect. Difference (approximating to differentiation) between the input signal before sampling and the sampled input signal is calculated and a differentiation component of even order distortion of the memory effect is approximated. The results thereof are linearly combined to thereby approximate inverse characteristics of the even order distortion of the memory effect.
A digital input signal outputted from an OFDM modulator 1 provided in a distortion compensation circuit 38 included in a modulator of the present invention is modulated by an orthogonal modulator (orthogonal modulation) 4 and is supplied to an adder 22 and a delay unit 18 through a delay unit 44 and a digital up converter 41 . The input signal delayed by the delay unit 18 is inputted to a multiplier 30 and a multiplier 34 for detecting a distortion coefficient. An output signal of the adder 22 is supplied to an adder 3 and an output signal of the adder 3 is converted into an analog signal by a DAC 5 . Thereafter, the analog signal is outputted from the distortion compensation circuit 38 and is power-amplified to a prescribed level by a high-frequency power amplifier (power amplifier) 7 . An output signal produced by the power amplifier 7 passes through a directional coupler 8 and a BPF 9 to be transmitted as radio waves by an antenna 10 .
On the other hand, the signal distributed by or branching off from the directional coupler 8 is converted into a digital signal by an A/D converter (ADC) 14 . The converted signal is adjusted to be a signal having a proper level by an auto gain controller (AGC) 15 and is supplied to the multiplier 30 and the multiplier 34 for detecting the distortion coefficient.
Coefficients (magnitudes) of 3rd-order odd symmetrical distortion (A 3 , P 3 ) to 7th-order odd symmetrical distortion (A 7 , P 7 ) and 2nd-order even symmetrical distortion (A 2 , P 2 ) are detected independently from the input signal by an odd symmetrical distortion signal generation circuit 20 and an even symmetrical distortion signal generation circuit 23 , respectively. The detected odd symmetrical distortion coefficient and even symmetrical distortion coefficient are subjected to being cored by coring circuits 32 and 43 for only peak as shown in FIG. 5B , being adjusted to have the same delay as the signal of distortion (difference between input and feedback signals) in output of the adder 25 by means of delay units 45 and 46 , being multiplied by signals of distortion (difference between input and feedback signals) in output of the adder 25 by means of multipliers 30 and 34 and being added to odd symmetrical distortion coefficient and even symmetrical distortion coefficient in adders 48 and 49 , respectively, so that the detected odd symmetrical distortion coefficient and even symmetrical distortion coefficient become odd symmetrical distortion compensation signal and even symmetrical distortion compensation signal, respectively. The odd symmetrical distortion compensation signal and even symmetrical distortion compensation signal are added to the input signal in an odd symmetrical distortion addition circuit 36 and an even symmetrical distortion addition circuit 37 , respectively.
Since detection of the odd symmetrical distortion coefficient and addition of the odd symmetrical distortion are the same as the patent literature 1, the detailed description thereof is omitted and simple description thereof is made. Different points of the present invention are described centering on detection of the even symmetrical distortion coefficient and addition of the even symmetrical distortion.
Detection of coefficients of 2nd-order even symmetrical amplitude distortion (A 2 ) and 2nd-order even symmetrical phase distortion (P 2 ) in the even symmetrical distortion signal generation circuit 23 in FIG. 1A illustrating in a block diagram the transmitter of the embodiment of the present invention is described referring to FIG. 3 illustrating in a block diagram (amplitude differentiation and phase differentiation) an even symmetrical distortion generation circuit of the embodiment of the present invention.
The input signal is converted into a real signal of an absolute value of a complex signal by an absolute value circuit 51 . The converted real signal is supplied to a delay unit (D) 52 and an adder 54 , in which difference (approximating to differentiation) between the converted real signal and a real signal before one sample is calculated. The converted real signal is supplied to an inverse-of-effective-value calculation circuit 62 , which calculates an inverse of an effective value, which is multiplied by a difference output signal of the adder 54 in a multiplier 56 . Moreover, an output signal of the multiplier 56 is multiplied by the input signal in a multiplier 58 to calculate 2nd-order even symmetrical amplitude differentiation distortion coefficient.
Furthermore, the input signal is supplied to a delay unit (D) 53 and an adder 55 , in which difference (approximating to differentiation) between the input signal and the input signal before one sample thereof is calculated. Furthermore, the input signal is supplied to an inverse-of-effective-value calculation circuit 63 , which calculates an inverse of an effective value, which is multiplied by a difference output signal of the adder 55 in a multiplier 57 . An output signal of the multiplier 57 is multiplied by a coefficient of 0.6378 in a multiplier 59 to calculate 2nd-order even symmetrical amplitude differentiation phase distortion coefficient.
An output signal of the multiplier 58 and an output signal of the multiplier 59 are added in an adder 60 , which outputs coefficients of 2nd-order even symmetrical amplitude distortion (A 2 ) and 2nd-order even symmetrical phase distortion (P 2 ) of memory effect.
Referring to FIG. 1A illustrating in a block diagram the transmitter of the embodiment of the present invention, distortion addition is described. In FIG. 1A , the even symmetrical distortion signal of the current input signal outputted by the even symmetrical distortion signal generation, circuit 23 is cored by the coring circuit 43 to be supplied to the delay unit 45 , which outputs an even symmetrical distortion signal of a delayed input signal which is delayed by a (Cartesian) loop (transmission) delay. Furthermore, the even symmetrical distortion signal outputted by the delay unit 45 is multiplied by a (Cartesian) loop (transmission) delay error signal produced by the adder 25 in a multiplier 34 , which produces a (Cartesian) loop (transmission) delay even symmetrical distortion error signal. Moreover, the even symmetrical distortion signal of the current input signal is added to the (Cartesian) loop (transmission) delay even symmetrical distortion error signal in adder 48 , which produces an even symmetrical distortion signal of the current input signal considering the (Cartesian) loop (transmission) delay distortion error to be added to the current input signal in the adder 3 .
Further, in FIG. 1A , the odd symmetrical distortion signal of the current input signal outputted by the odd symmetrical distortion signal generation circuit 20 is cored by the coring circuit 32 and is supplied to the delay unit 46 , which produces an odd symmetrical distortion signal of the delayed input signal which is delayed by a (Cartesian) loop (transmission) delay. Further, the odd symmetrical distortion signal produced by the delay unit 46 is multiplied by a (Cartesian) loop (transmission) delay error signal produced by the adder 25 in a multiplier 30 , which produces a (Cartesian) loop (transmission) delay odd symmetrical distortion error signal. Moreover, the odd symmetrical distortion signal of the current input signal is added to the (Cartesian) loop (transmission) delay odd symmetrical distortion error signal in adder 49 , which produces an odd symmetrical distortion signal of the current input signal considering the (Cartesian) loop (transmission) delay distortion error to be added to the current input signal in the adder 22 .
In the embodiment of the present invention, orthogonal modulation, orthogonal demodulation, up/down frequency conversion, BPF, a phase device and an averaging circuit are not provided in the Cartesian loop and variation in envelope of the power supply voltage is followed at low delay. Further, since delay is short and stable, the delay units 18 , 45 and 46 for compensating the (Cartesian) loop (transmission) delay and the delay unit 44 for compensating the time constant (delay) in variation of ERR power supply voltage can be fixed.
Moreover, stabilization is attained in the class A steady state by means of the coring of the input signal instead of an averaging circuit and class AB peak is followed at low delay.
Consequently, the orthogonal modulation, the orthogonal demodulation and the averaging circuit are not provided in the Cartesian loop by providing digital frequency conversion, high-frequency band ADC and high-frequency band DAC as means for making compensation after orthogonal modulation and accordingly as shown in FIG. 4B illustrating in a schematic diagram envelope detection tracking (ERR) power supply voltage (approximating to the baseband input signal) of the high-frequency output signal of the high-frequency power amplifier, the time constant of memory effect distortion of the high-frequency power amplifier, the time constant of distortion compensation loop in which the orthogonal modulation, the orthogonal demodulation and the averaging circuit are not provided in the Cartesian loop and envelopes of the OFDM high-frequency input signal and the OFDM high-frequency output signal, symmetrical distortion and asymmetrical distortion can be detected independently and the delay in the Cartesian loop transmission for making compensation independently can be made short to the same degree as the time constant of the memory effect, the envelope detection tracking ERR time constant (delay) of the high-frequency output signal or class AB peak variation time constant (delay) not shown, so that even if the distortion improvement amount is increased, convergence is made in a short time.
Embodiment 2
Next, an embodiment 2 is described. Description of the same configuration and operation as the embodiment 1 is omitted and only different points are described.
Description of configuration and operation of the embodiment of the present invention is made referring to FIG. 1B illustrating in a block diagram the transmitter (orthogonal compensation ADC and orthogonal compensation DAC after orthogonal modulation) of the embodiment of the present invention instead of FIG. 1A illustrating in a block diagram the transmitter (digital frequency conversion, high-frequency band ADC and high-frequency band DAC of a digital up converter and a digital down converter in compensation after orthogonal modulation) of the embodiment of the present invention.
In FIG. 1B , a digital input signal produced by an OFDM modulator 1 provided in a distortion compensation circuit 38 included in a modulator of the present invention is modulated by an orthogonal modulator (orthogonal modulation) 4 and is supplied to a multiplier 2 and a delay unit 18 through a delay unit 44 . The input signal delayed by the delay unit 18 is supplied to the multiplier 30 and the multiplier 34 for detecting a distortion coefficient. An output signal of the multiplier 2 is inputted to an adder 3 and an output signal of the adder 3 is converted into an analog signal by a DAC 5 . Then, the analog signal is outputted from a distortion compensation circuit 38 and a frequency of the analog signal is converted by a mixer 40 and an oscillator 13 . The analog signal having the converted frequency is supplied to a BPF 6 to remove unnecessary waves or signals therefrom and is amplified to a prescribed power level by a high-frequency power amplifier (power amplifier) 7 . An output signal produced by the power amplifier 7 passes through a directional coupler 8 and a BPF 9 and is transmitted as radio waves by an antenna 10 .
On the other hand, a signal distributed by or branching off from the directional coupler 8 is subjected to frequency conversion by means of a mixer 11 and the oscillator 13 and is supplied to a BPF 12 to remove unnecessary waves or signals therefrom. Then, the signal produced by the BPF 12 is inputted to the distortion compensation circuit 38 included in the modulator. The signal inputted to the distortion compensation circuit is converted into a digital signal by an orthogonal compensation A/D converter (ADC) 14 . The converted signal is adjusted to be a signal having a proper level by an auto gain controller (AGC) 15 and is supplied to an adder 25 .
In the embodiment of the present invention, orthogonal modulation, orthogonal demodulation, a phase device and an averaging circuit are not provided in the Cartesian loop and variation in envelope of the power supply voltage is followed at low delay. Further, since delay is short and stable, the delay units 18 , 45 and 46 for compensating the (Cartesian) loop (transmission) delay and the delay unit 44 for compensating the time constant (delay) in variation of ERR power supply voltage can be fixed.
Moreover, stabilization is attained in the class A steady state by means of the coring of the input signal instead of an averaging circuit and class AB peak is followed at low delay.
Consequently, the orthogonal modulation, the orthogonal demodulation and the averaging circuit are not provided in the Cartesian loop by providing the orthogonal compensation ADC and the orthogonal compensation DAC as means for making compensation after orthogonal modulation and accordingly as shown in FIG. 4B illustrating in a schematic diagram an envelope detection tracking (ERR) power supply voltage (approximating to the baseband input signal) of the high-frequency output signal of the high-frequency power amplifier, the time constant of memory effect distortion of the high-frequency power amplifier, the time constant of distortion compensation loop in which the orthogonal modulation, the orthogonal demodulation and the averaging circuit are not provided in the Cartesian loop and envelopes of the OFDM high-frequency input signal and the OFDM high-frequency output signal, symmetrical distortion and asymmetrical distortion can be detected independently and the delay in the Cartesian loop transmission for making compensation independently can be made short to the same degree as the time constant of the memory effect, the envelope detection tracking ERR time constant of the high-frequency output signal or class AB peak variation time constant not shown, so that even if the distortion improvement amount is increased, convergence is made in a short time.
According to the present invention, without being limited to the embodiments 1 and 2, in the distortion pre-compensation circuit which independently forms coefficients of the odd symmetrical distortion compensation signal of each order of the high-frequency power amplifier which amplifies the input signal at high-frequency band, the present invention can be widely applied to the distortion pre-compensation circuit which independently forms plural coefficients of the compensation signal of even order distortion of the memory effect of the input signal.
INDUSTRIAL APPLICABILITY
Specifically, the present invention can be widely applied to the transmitter of large power in digital modulation in which the ratio band for a ratio between a center frequency and a signal band is high without being extremely different from 1 and a difference between peak power and average power is large as in a transmitter for 400 W-multimedia broadcasting having the frequencies of 90 MHz to 108 MHz and 208 MHz to 222 MHz or the like.
REFERENCE SINGS LIST
1 : OFDM modulator (digital output of OFDM-MOD),
92 : SWR AC in ERR POWER SUPPLY VOLTAGEout,
4 : orthogonal modulator (orthogonal modulation),
5 , 91 : D/A converter (DAC),
16 : orthogonal demodulator (orthogonal demodulation),
11 , 40 : mixer,
6 , 9 , 12 : BPF,
13 : oscillator,
14 : A/D converter (ADC),
15 : auto gain controller (AGC),
7 : high-frequency power amplifier (power amplifier),
8 : directional coupler,
10 : antenna,
2 , 21 , 24 , 27 30 , 34 , 56 , 57 , 58 , 59 61 , 69 : multiplier,
3 , 22 , 25 , 42 48 49 54 , 55 , 60 , 74 , 75 , 80 , 82 : adder,
20 : odd symmetrical distortion signal generation circuit,
23 : even symmetrical distortion signal generation circuit,
31 , 35 , 65 : averaging circuit;
36 : odd symmetrical distortion addition circuit,
37 : even symmetrical distortion addition circuit,
41 : digital up converter,
38 : distortion compensation circuit included in modulator,
47 : distortion compensation signal generation circuit,
32 , 43 : coring circuit,
19 : square circuit,
51 : absolute value circuit,
62 , 63 , 67 : inverse-of-effective-value calculation circuit,
17 : phase shifter,
18 , 44 , 45 , 46 , 52 , 53 , 72 , 73 : delay unit,
66 : circuit for automatically calculating fixed value of 0.6378,
68 : circuit for automatically calculating fixed value of 0.7996. | The purpose of the invention is to reduce Cartesian loop transmission delay for compensating the distortion occurring in a high-frequency power amplifier and make the distortion compensation converge quickly, thereby increasing the efficiency. A transmission device has: a high-frequency power amplifier; a pre-distortion compensation circuit for independently generating the coefficients of the distortion compensation signal for each order of the odd and even symmetric distortions of the high-frequency power amplifier; a means for varying the power supply voltage of the high-frequency power amplifier with an orthogonal modulation OFDM input signal; a digital frequency converter; a high-frequency band ADC; and a high-frequency band DAC. In the transmission device, an error distortion compensation signal is created from the output of the high-frequency power amplifier and the orthogonal modulation OFDM input signal, and a delay device is inserted at the previous stage of a distortion compensation circuit, said delay device having a delay equivalent to a time constant for varying the power supply voltage of the high-frequency power amplifier with the orthogonal modulation OFDM input signal. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed generally to a system and method for inspecting an optical fiber. More particularly, the present invention is directed to automating the inspection of an optical fiber, advantageously including inspecting an epoxy area surrounding the optical fiber, while providing repeatability of the inspection, simplicity of assessing results of the inspection, and insuring, upon passing the inspection, a high-quality, durable fiber.
2. Description of Related Art
Optical fibers are widely employed to transmit light for many applications. The demand for inexpensive, reliable, high-performance optical fibers continues to grow.
A cross-section of a typical optical fiber is shown in FIG. 1. The optical fiber includes a core region 102 surrounded by a cladding region 104. Both the core region 102 and the cladding region 104 may be manufactured out of glass. The core region 102 is typically very small, e.g., about four to nine microns in diameter for a single mode fiber. The cladding region 104 typically has a larger diameter than the core region, e.g., about 125 microns in diameter. The cladding region 104 may be surrounded by a supporting structure or ferrule region 108 which protects the core region 102 and the cladding region 104 from damage. The ferrule region 108 may be made of zirconia and may be approximately 2500 microns in diameter. The ferrule region 108 may be attached to the cladding region 104 by an epoxy layer 106.
In order to insure good performance of the optical fiber, the optical fiber needs to be relatively free of defects such as scratches, blobs, cracks, chips, pits, dirt, and other discontinuities/irregularities. The presence of such defects in the optical fiber, particularly in the core region, may result in at least one of increased insertion loss, poor return loss, and premature failure due to the increase of the regions having defects. This increase in the regions having defects may be the result of environmental or mechanical stresses.
Initially, optical fibers were inspected manually by viewing them under a microscope. Such manual inspection has the obvious drawbacks of being time consuming, subjective, not very repeatable, and limited by human visual acuity.
U.S. Pat. No. 5,179,419 discloses a method for detecting, classifying and quantifying defects in an optical fiber. This method provides quantitative information regarding the discontinuities on the optical fiber, but does not provide a qualitative guide for a user. Thus, while the inspection itself is automated, the ultimate conclusion of acceptability of the optical fiber is left to the user. The generation of all of the quantitative information is also quite time consuming.
Another problem with both automated and manual inspection systems is the reliability in terms of repeatability. In other words, the same inspection performed on the same fiber may yield different results.
Further, now that optical fibers have been in use for many years, some of those optical fibers inserted into ferrules or other supporting structures which initially were deemed acceptable have begun to fail. With the increasing use of optical fibers in ferrules or other supporting structures, there is also a need to assess additional long term performance of these optical fibers. One such factor in determining long term performance is the evenness of a layer used to secure the fiber in the supporting structure and to eliminate any resulting gap between the supporting structure and the fiber inserted therein, herein referred to as an epoxy layer. Current approaches for analyzing end surfaces do not take into account the long term effect of any uneven distribution of the epoxy layer or even suggest how to reliably analyze the epoxy layer.
SUMMARY OF THE INVENTION
The present invention is therefore directed to an inspection system and method for optical fibers which substantially overcomes one or more of the problems due to the limitations and disadvantages of the related art.
It is another object of the present invention to provide an inspection method and system for optical fibers which requires the core to be free of intensity variations, while tolerating some intensity variations in the cladding region.
It is yet another object of the present invention to provide an inspection system and method which uses software algorithms to provide real-time processing.
It is still another object of the present invention to provide an inspection system and method which provide a qualitative determination for a user.
It is further an object of the present invention to provide an inspection system and method for optical fibers which has good repeatability and fully removes operator subjectivity.
It is another object of the present invention to provide an inspection system and method for optical fibers in supporting structures which can assess long term performance. In particular, it is an object of the present invention to account for the known physical fact that an uneven epoxy distribution between the fiber and the supporting structure can leave uncured residuals which greatly reduce the reliability of the optical interface, especially over an extended period of time.
It is another object of the present invention to indicate the acceptability of illumination parameters of the fiber, particularly prior to the start of inspection.
One or more of the above, as well as other, objects may be realized by a method for inspecting an optical fiber in a supporting structure including analyzing a thickness of an epoxy layer between the optical fiber and the supporting structure and determining acceptability of the optical fiber in accordance with the analyzing. The analyzing may include imaging the epoxy layer. The supporting structure may be a ferrule and the imaging may include imaging the ferrule and the epoxy layer. The analyzing may include unpolarizing an image of an annulus formed by the epoxy layer. The analyzing may include calculating statistical parameters regarding a variation in the thickness of the epoxy layer around the optical fiber.
One or more of the above, as well as other, objects may be realized by a method for determining centering of an optical fiber relative to an illumination source including comparing illumination levels between at least three points around a periphery of the optical fiber and determining whether centering of the optical fiber relative to the illumination source is within a predetermined level. When the determining indicates that the centering is not within the predetermined level, the optical fiber and the illumination source may be moved relative to one another. The determining may include generating a standard deviation between an average of the illumination levels at the at least three points.
One or more of the above, as well as other, objects may be realized by a method of analyzing scratches in a region of an optical fiber including providing an array of pixels around a pixel of interest, with the pixel of interest being in a center of the array, averaging intensities of pixels surrounding the pixel of interest, multiplying an averaged intensity by a weighting factor to form a threshold, comparing an intensity of the pixel of interest to the threshold, and flagging the pixel of interest when the intensity of the pixel of interest exceeds the threshold. These steps of providing, averaging, multiplying, comparing and flagging may be repeated for each pixel in the region. The flagged pixels may then be Hough transformed. Features formed by Hough transformed pixels of less than a predetermined linear length may be ignored. The method may include rank filtering features formed by Hough transformed pixels. When more than one feature remains after ignoring short features, the remaining features may be morphologically filtered using a structuring element.
One or more of the above, as well as other, objects may be realized by a method of identifying a feature in a region of a fiber as a scratch including capturing an image of the fiber, Hough transforming features having an intensity exceeding an average intensity in the region by a predetermined amount, thresholding Hough transformed features below a predetermined level, rank filtering Hough transformed features, morphological filtering, when more than one feature remains after said thresholding, closest features using a structuring element, and identifying any features remaining after the morphological filtering and having a length greater than a predetermined length as a scratch. The average intensity may be computed from an array of pixels neighboring a feature. The morphological filtering may include determining a peak value of dimensions in a Hough domain for a feature closed by the structuring element, comparing the peak value to a predetermined multiple of a standard deviation of the dimensions, and ignoring features for which the peak value does not exceed the predetermined multiple of the standard deviation.
One or more of the above, as well as other, objects may be realized by a method of inspecting a fiber including acquiring an image of the fiber, identifying defects in the fiber by intensity variations, rejecting a fiber having any defects in a core region thereof, and subjecting defects in a clad region of the fiber to a two-dimensional discrimination analysis. The two-dimensional analysis may have a cumulative dimension along which a total of the defects is not to exceed a first predetermined value and an individual dimension along which each defect is not to exceed a second predetermined value. A fiber having defects which fail in either dimension will be rejected. The identifying may include determining whether a defect is a blob or a scratch. When the defect is a scratch in the clad region, the individual dimension may be a length of the longest scratch and the cumulative dimension may be a total number of scratches. When the defect is a blob in the clad region, the individual dimension may be an area of the largest blob and a cumulative dimension may be a cumulative blob area. The core region may be defined as some multiple of a core diameter of the fiber. When the fiber is inserted in a supporting structure, the method may include inspecting a layer between the fiber and the supporting structure.
One or more of the above, as well as other, objects may be realized by a method for indicating acceptability of illumination parameters of an optical fiber being illuminated to a user prior to image capture of the optical fiber including displaying scales with ranges for each illumination parameter and displaying an indicator for each image parameter indicating a current value of that illumination parameter. The illumination parameters may be for an end surface of the optical fiber. A green region in each of the scales indicating an acceptable region may be provided.
One or more of the above, as well as other, objects may be realized by a method of initializing an imaging system for a fiber being illuminated including finding an illumination level of the fiber and determining whether the fiber is properly centered in the illumination. Finding the illumination level may include determining an average illumination of the core and an average illumination of the cladding. The acceptability of the contrast and/or the brightness of the fiber may be assessed.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, aspects and advantages will be described with reference to the drawings, in which:
FIG. 1 is a cross-section of an optical fiber in a ferrule;
FIG. 2 is a schematic diagram of an inspection system in accordance with the present invention;
FIG. 3A is a flow chart illustrating a method of initialization for inspection in accordance with the present invention;
FIG. 3B is a screen displaying meters;
FIG. 4 is a flow chart illustrating the overall flow of the inspection in accordance with the present invention;
FIG. 5 is a flow chart illustrating a method for inspecting the epoxy layer in accordance with an embodiment of the present invention;
FIG. 6A illustrates the extraction of the epoxy layer with adjacent regions surrounding the epoxy layer;
FIG. 6B illustrates the region shown in FIG. 6A after unpolarization in accordance with an embodiment of the present invention;
FIG. 6C illustrates the epoxy layer extracted from the region in FIG. 6B;
FIG. 6D is the y-axis projection of the epoxy layer in FIG. 6C;
FIG. 6E is the x-axis projection of the epoxy layer in FIG. 6C;
FIG. 7 is a flow chart illustrating a method for analyzing scratches on the fiber in accordance in the present invention;
FIG. 8 is a plot illustrating an example of the decision criteria regarding scratches in the cladding region in accordance with an embodiment of the present invention;
FIG. 9A is a flow chart illustrating a method for analyzing blobs on the core zone of the fiber in accordance in the present invention;
FIG. 9B is a flow chart illustrating a method for analyzing blobs on the clad zone of the fiber in accordance in the present invention; and
FIG. 10 is a plot illustrating an example of the decision criteria regarding blobs in the cladding region in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the present invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications, and embodiments within the scope thereof and additional fields in which the invention would be of significant utility without undue experimentation.
FIG. 2 is a schematic illustration of an embodiment of a system 110 used to perform the inspection in accordance with the present invention. The system 110 includes a fiber imager 112, a computer 114, a display 116 and a user input 118. The fiber imager illuminates the fiber to be inspected and captures an image of the illuminated fiber. The fiber imager may be, for example, the imager disclosed in U.S. Pat. No. 5,724,127, which is hereby incorporated by reference in its entirety. The fiber imager 112 provides an image of the optical fiber to the computer 114, which stores and processes the image. The computer 114 displays this image on the display 116. The display 116 represents the image using an array of picture elements (pixels) which typically vary in intensity from 0, representing black, to 255, representing white. The user input 118 may be used to provide information regarding the fiber to be inspected, to begin testing, etc.
FIG. 3A is a flow chart illustrating a method of initializing the inspection. If step 119 determines that the test is not to be started, the method proceeds to step 120. In step 120, the image of the fiber is grabbed by the fiber imager and sent to the computer. The fiber center, the fiber size and the core size are determined by known techniques in step 122. In step 124, the size of the fiber determined in step 122 is compared to a range of fiber sizes to insure that the object being centered on is the fiber. Alternatively, a user may input an expected fiber size and step 124 compares the size determined in step 122 to a range surrounding the expected fiber size to insure that the object being centered on is the fiber. If not, the flow proceeds to step 125 which outputs a warning on the display indicating that the imager is apparently centered on something other than the fiber.
If the fiber diameter is within the expected range, whether predetermined or input, the flow proceeds to section 126 in which the illumination parameters of the fiber are determined. These illumination parameters are then used to derive various meters regarding the illumination of the fiber.
In step 126a, the overall illumination level of the fiber is found. The core and clad zones are extracted and the average pixel level is calculated for each zone. This illumination level is used to normalize the illumination values of other parameters to be determined so that the results of the inspection will not be affected by variations in the illumination level between different inspections. The illumination level may be adjusted by controlling the output of the light source and/or by altering a distance between the light source and the fiber.
In step 126b, the illumination at a number of points, e.g., six, around the edge of each region of the fiber are compared to an average of the illumination at these points in order to determine a standard deviation of illumination around the fiber. In particular, the standard deviation around the core and the standard deviation around the cladding are determined. It is important to insure that the fiber is illuminated as evenly and as directly as possible. If the fiber is illuminated at an angle, one portion of the fiber may overshadow another portion. While image processing can eliminate this shadow, if a defect is present in the shadowed potion, this defect may not appear in the image after the shadow has been removed. Therefore, placing a fiber too far off of the center of illumination can lead to variable results and lower repeatability. Advantageously, the relative position of the fiber and the illumination source is adjusted until the standard deviations are acceptable.
In step 126c, the focus factor is calculated by determining the image intensity gradient. The strength of this image intensity gradient at the fiber edges, e.g., the edge of the core region and the edge of the clad region, serves as the focus factor.
In step 128, a number of meters which are needed to insure a valid inspection in accordance with the present invention are derived based on the illumination parameters acquired in section 126. For example, the acceptability of the position of the fiber is derived based on the standard deviation, where the smaller the deviation, the better the position. A standard deviation around each region of the fiber within, for example, 5%, indicates the fiber is sufficiently centered to insure good repeatability and viewing of all intensity variations. Whether the fiber is in or out of focus is derived based on the focus factor, where the higher the focus factor representing the sharpness at the edges, the more in focus the fiber. The brightness of the overall image is derived from the illumination level, and cannot be so low such that some intensity variations may not be detected or so high such that some intensity variations may be washed out. The contrast is derived based on the illumination averages inside and outside the fiber, and cannot be so high or so low such that some intensity variations may not be detected.
Finally, in step 130, the imaging meters which have been derived may be displayed on the display 116, preferably on relative scales for ease of comprehension by a user. For example, as shown in FIG. 3B, the illumination may be displayed on a scale 132 from "dark" to "bright" with an acceptable region being indicated there between in green, the focus may be displayed on a scale 134 from "out of focus" to "in focus" with an acceptable region near and including the "in focus" end being indicated in green, the contrast may be displayed on a scale 136 from "low contrast" to "high contrast" with an acceptable region being indicated there between in green, and the centering of the fiber relative to the illumination source may be displayed on a scale 138 from "bad position" to "good position" with an acceptable region near and including the "good position" end being indicated in green. The display 116 may also include an image of the fiber itself in a portion 131 of the display.
An indicator 133, 135, 137, 139 for each meter informs the user as to the current values of the imaging parameters on these scales. When each of the indicators is in a corresponding green region, the initialization is complete. If a manual mode of operation has been selected, the user will then adjust the fiber and/or the illumination source in response to any of the meters which were not indicated as being acceptable. If an automatic mode of operation has been selected, the fiber and/or the illumination source are automatically adjusted until all meters are acceptable and the display indicates to the user that the fiber is ready to be inspected.
If step 119 indicates testing or inspecting is to be started, the method proceeds to the flow chart shown in FIG. 4. The start of inspection may be user initiated or may be automatically instituted upon successful completion of the initialization, i.e., all of the meters are deemed acceptable. The initialization in accordance with the present invention insures repeatability and compensates for any defects in the optical system.
FIG. 4 is a flow chart showing the inspection method in accordance with the present invention. This inspection includes a preprocessing portion 140, an epoxy analysis 200, a scratch analysis 300, a blob analysis 400 and a displaying of results 500.
The preprocessing portion 140 is desirable to remove noise, increase repeatability and/or guarantee image features are the same. The preprocessing portion 140 includes a step 142 of grabbing multiple, e.g., fifteen, images of the fiber under unvarying conditions, a step 144 of averaging the images from step 142, and a step 146 of rank filtering the averaged image from step 144 to remove noise therefrom. This filtered image from step 146 is preferably the one used for the testing portions of the inspection.
While the testing portions shown in FIG. 4 are shown as being performed in parallel, the test may also be run sequentially in any order. Further, while FIG. 4 indicates that all of the tests are performed in a comprehensive mode, if the tests are performed sequentially and a user does not want all available information regarding the optical fiber but only cares if the fiber is acceptable, as soon as one of the criteria discussed below is not met, the inspection can proceed to the display step 500 and indicate that the fiber is unacceptable. Any subsequent references to a comprehensive mode in which all tests are performed are to be understood in relation to sequential processing only.
The first test shown in FIG. 4, the epoxy analysis 200, is a unique concept to the inspection of the present invention. When fibers are inserted into ferrules or other supporting structures, as shown in FIG. 1, they inevitably do not fit perfectly therein. In order to eliminate a resulting air gap between the fiber and the ferrule, as well as to secure the fiber to the ferrule, an epoxy is applied to form the epoxy layer 106. Evidence shows that failure of the epoxy layer 106 to be evenly distributed around the fiber is one key reason which gives rise to the problem of optical connector reliability.
Two fundamental failure modes are generated from uneven or inappropriate epoxy distribution. The first failure mode occurs along the fiber axis and results in permanent fiber withdrawal of up to 100 nm (according to Bellcore/TCA 1996 analysis of fiber optic reliability standard workgroup). The second failure mode occurs in the plane perpendicular to the fiber axis and results in lateral air gaps and stresses which contribute to accelerated cracking and fissure of the fiber media. These failure modes are further accelerated by environmental and mechanical stresses encountered by the fiber in use, such as changes in pressure, humidity, temperature, etc. Previous inspection methods discard image data from the transition zone between the cladding and the ferrule or other supporting structure. In accordance with the present invention, this data is used to analyze the epoxy layer as a further key parameter of interest in assessing long term reliability of an optical fiber as discussed below.
FIG. 5 is a flow chart illustrating a method of inspecting the epoxy area of an optical fiber, such as the optical fiber shown in FIG. 1. As can be seen therein, this inspecting method involves extracting the epoxy area in step 202, unpolarizing the extracted epoxy area in step 204, extracting the epoxy layer from the unpolarized area in step 206, projecting the extracted epoxy layer in step 208, and calculating a standard deviation and gradient at step 210. Each of these steps will be discussed in detail below.
When imaged, the epoxy area is darker than the ferrule, which is bright white. The computer 114 may extract the epoxy area in accordance with step 202 by determining where this boundary indicated by the dark epoxy area is located or by assuming this epoxy is at the periphery of a perfectly circular fiber having the fiber diameter and center determined in the initialization. A predetermined amount, e.g., eight pixels, of image data on either side of this boundary are also extracted. A number of pixels are needed since the epoxy layer varies in thickness and to account for imperfections in the circularity of the fiber. FIG. 6A illustrates the annulus 250 resulting from this extraction. The annulus 250 contains all of the image data of the epoxy area in area 252, as well as image data from the clad region adjacent the epoxy area in area 254 and image data from the ferrule region adjacent the epoxy area in area 256. Typically, the inner ring of the annulus 250 sufficient to capture the epoxy area will have a diameter of approximately 90% of the fiber diameter and the outer ring of the annulus 250 will have a diameter of approximately 110% of the fiber diameter.
The computer 114 then can "unpolarize" this extracted data in accordance with step 204, i.e., project the annulus resulting from the extraction as shown in FIG. 6A into a linear representation as shown in FIG. 6B. From this linear representation, the computer 114 can then extract the epoxy region 252 from the linear image in accordance with step 206 by extracting the intensities which are lower than the intensity in the bright ferrule region and which vary from the intensity of the clad region. FIG. 6C illustrates the extracted epoxy layer 252.
While the epoxy region 252 is shown as a layer having an even thickness in FIGS. 6A and 6B, in practice and as shown in FIG. 6C, the epoxy will vary in thickness. Therefore, in order to most readily assess how much the thickness is varying by along the layer, the extracted epoxy region is projected in accordance with step 208 along the y-axis into a plot of thicknesses centered on the average thickness T as shown in FIG. 6D and along the x-axis as shown in FIG. 6E, where the bottom line represents a thickness of zero. The smoothness of the distributions in FIG. 6C-6E will depend upon the number of sampling points taken along the x-axis.
Once the distribution of the thickness has been generated as shown in FIG. 6D and 6E, various parameters describing the distribution may be determined in accordance with statistical analysis principles. For example, in accordance with step 210, the half-peak-width, i.e., the width of the distribution where the number of occurrences falls off to half of the peak occurrences, of the y-axis projection, the standard deviation of the x-axis projection, and gradients of the x-axis projection, i.e., Δy/Δx, are determined. All of the noted parameters provide information regarding the shape of the distribution.
An example of the criteria used in evaluating this distribution is as follows. The half peak width of the y-axis projection should be less than some percentage, e.g., 0.5-20%, of the fiber diameter. The standard deviation of the x-axis projection should be less than some percentage, e.g., 0.5-20% of the fiber diameter. The maximum gradient of the x-axis projection should be less than the tangent of an angle indicating significant slope, e.g., an angle greater than between 30° and 60°. If any one of these criteria is not met, then the fiber will fail.
Step 212 assesses whether the fiber has failed the epoxy test or not. If the fiber has failed the epoxy test, step 214 determines whether the system is operating in a comprehensive mode. If the system is not operating in the comprehensive mode, the result that the fiber has failed the inspection is output to the display step 500. If the system is operating in the comprehensive mode or if the fiber has passed the epoxy analysis, step 216 determines whether all steps have been performed. If not, the inspection proceeds to the next test. If all tests have been completed, the inspection proceeds to the display step 500.
The inspection of the present invention also examines the core and cladding regions for intensity variations therein. These intensity variations fall into two general categories, scratches and blobs. Scratches are usually very straight and have a higher intensity than the surrounding area. For the inspection in accordance with the present invention, a scratch is defined as a linear feature having a predetermined minimum length that is wide enough to be detected by the optical power of the inspection system. This minimum length is determined in accordance with a desired sensitivity of the inspection. A blob is any non-uniform distribution of light intensity other than a scratch, including pits, chips, cracks, dirt, etc.
In accordance with the present invention, the inspection analyzes a core region or zone, including and extending beyond the core, and a clad region or zone for defects. This is to account for the fact that the closer to the core a defect occurs, the more intolerable the defect, while only requiring two sets of decision criteria. There are different levels of acceptable presence of discontinuities for the core region and the clad region. In accordance with a preferred embodiment, the core region is some multiple, e.g., 1.5-25, times the diameter of the core from the center of the fiber, and the cladding region is defined by an annulus having an inner diameter which is the diameter of the core region and an outer diameter which is approximately 90% of the diameter of the fiber. The larger the core region, which has stricter criteria than the clad region, the more likely a fiber will be to fail the inspection. Similarly, the larger the outer diameter of the clad region, the more likely the fiber will fail inspection. Thus, the determination of these regions is based on the strictness of the inspection desired. When either of these tests is to be performed, the pixels in both regions are scanned in one pass and stored for use in the respective analyses.
FIG. 7 is a flow chart illustrating the details of the scratch analysis 300 in accordance with the present invention. Step 302 performs an edge extraction in the following manner. An array of pixels, e.g., three by three pixels, is arranged having a pixel of interest in the center thereof. The intensities of the non-central pixels are averaged. If the center pixel has an intensity greater than the averaged intensity times a weighting value, the pixel is flagged as being part of an edge. Otherwise, the pixel does not constitute an edge. The weighting value may vary in accordance with a desired sensitivity, but may be, for example, 200. Such an edge extraction scheme addresses the problem of dealing with the transition zone between the core and the cladding that is part of the core zone, such that this transition zone will not qualify as an edge.
In step 304, the edges extracted by the step 302 are subjected to a filtered Hough transform so that presence of valid scratches may be determined. A Hough transform converts features from a spatial domain into a domain in which a feature is represented by its radial distance and angle from a set reference point. These values are then binned, such that a straight line, which have many points with similar radial distances and angles, will appear in the same bin, forming a spot in the transformed domain. These binned values are subjected to a hard thresholding to eliminate all bins without a sufficient number of points to qualify as a possible scratch. The number of points in this domain indicates the length of the edge, with the hard threshold being the number required being the number needed for the predetermined minimum length. After the hard thresholding, the binned values are also rank filtered to remove noise and smooth the data.
If there is more than one bin remaining after the hard thresholding, the remaining bins must be analyzed to determine whether each is a separate scratch. For example, a thick line or a long line may appear as more than one line. Alternatively, not all blobs may have been eliminated by the edge extraction. To help compensate for these potential discrepancies, bins that are close to one another are subjected to morphological filtering. The morphological filtering closes regions that are close enough to each other based on structuring elements, e.g., a rectangle. Bins within a closed region are connected to form a single feature. If a peak value for the radius and angle for the single feature is not greater than some multiple, e.g., 2-4.5, of the standard deviation of the radius and angle, this single feature is more likely to be a blob, and is eliminated from consideration as a scratch.
Any features which are not eliminated by the filtering in the filtered Hough transform step 304 are inverse Hough transformed at step 306 so that the scratches can be inspected and/or visualized by a user. These scratches may then again be assessed to determine if they are of sufficient length. Step 308 then performs a core transmission effect filtering to eliminate any remaining features below an illumination threshold due to scattered or direct illumination, as a scratch will be very bright after the inverse Hough transform. If step 310 determines that there are any scratches in the core zone, the fiber fails the core scratch test. If the fiber fails the core scratch test, step 312 determines whether the comprehensive mode is in use. If not, the inspection indicates to the display step 500 that the fiber has failed. If the comprehensive mode is used or there are no scratches in the core zone, the inspection proceeds to analyzing scratches in the clad zone. While the clad zone scratch test has been shown as following the core zone scratch test, these tests may proceed in parallel or in any order relative to the other tests.
While the clad zone in accordance with the present invention is outside the core-cladding transition zone, a clad zone edge extraction step 314 needed to insure that the epoxy layer is not inadvertently considered to be a scratch. The clad zone edge extraction 314 is the same as the core zone edge extraction discussed above, although a different weighting value could be used. The edges are subjected to a filtered Hough transformed in step 316 in a similar manner as discussed above regarding step 304. The scratches not eliminated by the filtered Hough transform of step 316 are inverse Hough transformed in step 318.
Step 320 determines the number of scratches in the clad zone and the length of the longest scratch in the clad zone. An example of the criteria used to determine if these scratches are acceptable is shown in FIG. 8. If the longest scratch in the clad zone equals or exceeds x s , the fiber will fail the clad zone scratch test. Additionally, if there are more than y s scratches in the clad zone, the fiber will fail the clad zone scratch test. The selection of x s and y s depends upon the desired selectivity of the inspection. The smaller x s or y s , the tougher the criteria, so the more selective the inspection, i.e., more fibers will fail the clad zone scratch test and be rejected. As an example, the length x s which the longest scratch must be less than may be equal to some multiple, e.g., 0.5-10, of the core diameter, and the number of scratches y s may be, e.g., 2-20.
If the fiber fails, step 322 determines whether the comprehensive mode is in use. If not, the inspection indicates to the display step 500 that the fiber has failed. If the comprehensive mode is used or the fiber has an acceptable level of scratches in the clad zone, step 324 determines whether all tests have been completed. If not, the inspection proceeds to the next test. If all tests have been completed, the inspection proceeds to the display step 500.
FIG. 9A is a flow chart illustrating the blob analysis for the core zone in accordance with the present invention. Step 402 extracts the core zone and preferably includes core discrimination in which the average illumination in the core itself is subtracted from the pixels in the core itself. Since the following blob test is based on deviations from the average intensity, the core discrimination removes the bias of the illumination of the core itself. For example, if the core is bright, bright blobs may not be detected.
Step 404 detects potential blobs adaptively by searching for regions within the core zone which vary, either above or below, in intensity from the local average intensity by a predetermined amount. The predetermined amount may be set based on a desired sensitivity, and is preferably some multiple, e.g., 0.5-1.5, of the local standard deviation. The number of adjacent or neighboring pixels that constitute the local area considered in the adaptive detection is a trade-off between speed and the needed sensitivity. Step 406 then size thresholds the regions from step 404 to eliminate scratches and noise. Step 408 determines if there are any blobs in the core zone after the size threshold of step 406. If there are blobs in the core zone, the fiber will fail the core zone blob test.
If the fiber fails the core blob test, step 410 determines whether the comprehensive mode is in use. If not, the inspection indicates to the display step 500 that the fiber has failed. If the comprehensive mode is used or there are no blobs in the core zone, step 412 determines whether all of the tests have been performed. If not, the inspection proceeds to the next test. If all tests have been completed, the inspection outputs the results to the display 500.
FIG. 9B is a flow chart illustrating the blob analysis for the clad zone. Step 414 extracts the clad zone. Step 416 adaptively detects potential blobs by searching for regions within the clad zone which vary from the local average intensity by a predetermined amount. The predetermined amount may be set based on a desired sensitivity, and is preferably some multiple, e.g., 0.5-1.5, of the local standard deviation. The number of adjacent or neighboring pixels that constitute the local area considered in the adaptive detection is a trade-offbetween speed and the needed sensitivity. Step 418 then size thresholds the regions from step 416 to eliminate scratches and noise, e.g., the blob must be more than a few pixels wide, or whatever the expected width of the widest scratch. Step 420 determines the size of the biggest blob and the total area of all of the blobs from step 418.
An example of the criteria used to determine if these parameters are acceptable is shown in FIG. 10. If the biggest blob in the cladding region exceeds x b , the fiber will fail the clad zone blob test. Additionally, if the total area of all of the blobs within the clad zone exceeds y b , the fiber will fail the clad zone blob test. The selection of x b and y b depends upon the desired selectivity of the inspection. The smaller x b or y b , the tougher the criteria, so the more selective the inspection, i.e., more fibers will fail the clad zone blob test and be rejected. Obviously, for the criteria y b to be meaningful, it needs to be larger than x b . As an example, the largest blob size may not exceed a multiple, e.g., 0.25-5, of the core area, and the cumulative blob area may not exceed a multiple, e.g., 0.5-15, of the core area.
If the fiber fails, step 422 determines whether the comprehensive mode is in use. If not, the inspection indicates to the display step 500 that the fiber has failed. If the comprehensive mode is used or the fiber has an acceptable level of scratches in the cladding region, step 424 determines whether all tests have been completed. If not, the inspection proceeds to the next test. If all tests have been completed, the inspection proceeds to the display step 500.
Once all of the tests have been completed, or once the fiber has failed any of the tests when not in the comprehensive mode, the inspection proceeds to the display step 500. In the display step 500, the end result of the fiber passing or failing is indicated, with or without indication as to which test the fiber failed. If in the comprehensive mode, the display can also indicate the pass/fail status for each test. One of ordinary skill in the art would realize that any number of displays which alerts the user to the acceptability of the fiber, including audible as well as visual indication, can be used.
As described above, the inspection in accordance with the present invention has numerous advantages. A definitive answer is provided to a user. The evenness of the distribution of the epoxy between the fiber and the supporting structure can be analyzed. The extent of scratches and blobs in the cladding zone can be analyzed without requiring extensive classification of each type of defect. Scratches can be readily assessed in the core and clad zones. The automated assessment of the clad region accounts for both a cumulative effect of each type of defect as well as a maximum parameter for a single defect, both of which must be met for the fiber to pass. Assessing the acceptability of illumination parameters during initialization prior to beginning inspection improves repeatability and accounts for any defects in the optics of the inspection system. Repeatability may also be increased by insuring centering of illumination and/or averaging successive images.
Although preferred embodiments of the present invention have been described in detail herein above, it should be clearly understood that many variations and/or modifications of the basic inventive concepts taught herein, which may appear to those skilled in the art, will still falls within the spirit and scope of the present invention as defined in the appended claims and their equivalents. | A system and method for inspecting an optical fiber, particularly an epoxy region of an optical fiber in a supporting structure. The inspection may use an initialization routine including determination of whether the centering between the optical fiber and the illumination source is sufficient. The meters used to determine completion of initialization may be displayed. The inspection may analyze the uniformity of the thickness of an epoxy layer between the fiber and the supporting structure. The inspection may also analyze the core and clad zones of the optical fiber for scratches and other intensity variations, referred to generically as blobs. The core zone preferably encompasses a region larger than the core alone, e.g., an area which is a multiple of the core diameter. Different criteria are established for the core and clad zones, with no discontinuities being tolerated in the core zone. Scratches may be extracted using a windowing technique. The clad zone has a two-dimensional discrimination factor for both scratches and blobs, one dimension being cumulative for a totality of the intensity variations and the other dimension being for each individual intensity variation. The effect of the illumination of the core on the discrimination may be accounted for. | 6 |
BACKGROUND OF THE INVENTION
The subject matter of the invention is a new process for the production of N-acetyl-2,3-dehydro-aminocarboxylic acid esters of the general formula: ##STR1## in which R 1 is a methyl or ethyl group, R 2 is hydrogen or a methyl group and R 3 is hydrogen, an alkyl group having 1 to 6 carbon atoms, an aryl group, an unsubstituted or substituted alkylmercapto group, e.g. the alkyl group has 1 to 6 carbon atoms, or an arylmercapto group.
Compounds of the general formula (I) are known. They serve chiefly as intermediate products for the production of optically active 2-N-acetylaminocarboxylic acids by asymmetrical catalytic hydrogenation of the prochiral C═C double bond.
It is also known already to produce N-acetyl-2,3-dehydro-aminocarboxylic acid esters in a two-step process by reaction of 2-azido-carboxylic acid esters with n-butyl-lithium/ethanol and subsequent acylation with acetyl chloride, (Manis et al, J. Org. Chem. Vol. 45 (1980), pages 4952-4954). In this manner there can be produced, for example, the N-acetyl-2,3-dehydro-alanine ethyl ester in a yield of 58% of theory.
SUMMARY OF THE INVENTION
The process of the invention is characterized by reacting a 2-azido-carboxylic acid ester of the general formula: ##STR2## in which R 1 , R 2 , and R 3 are as defined above, in the presence of rhenium VII sulfide and/or oxide and at a temperature between 50° and 150° C. with a mixture of one part by volume acetic anhydride and 1.5 to 5 parts by volume of acetic acid.
In this way it is possible to produce the desired N-acetyl-2,3-dehydro-aminocarboxylic acid ester of general formula (I) in a single step process easily and in high yield.
Examples of 2-azido-carboxylic acid esters of general formula (II) which can be reacted according to the process of the invention are, among others, the methyl and ethyl ester of 2-azido-propionic acid, 2-azido-butyric acid, 2-azido-3-methyl-butyric acid, 2-azido-3-phenyl-propionic acid, 2-azido-valeric acid, 2-azido-hexanoic acid, 2-azido-heptanoic acid, 2-azido-3-methylmercapto-propionic acid, 2-azido-3-methoxycarbonylmethylmercapto-propionic acid, 2-azido-nonanoic acid, 2-azido-8-methyl-nonanoic acid, 2-azido-3-ethylmercapto-propionic acid and 2-azido-3-hexylmercaptopropionic acid.
The rhenium VII sulfide and/or oxide serving as catalyst is used suitably in an amount between 0.01 and 10 mole percent based on the 2-azidocarboxylic acid ester of general formula (II) employed. The especially preferred amounts in the case of rhenium VII sulfide lie between 0.5 and 2 mole percent and in the case of rhenium VII oxide between 0.05 and 1 mole percent.
The process of the invention is preferably carried out at a temperature between 60° and 90° C. In order to avoid loss of yield through polymerization of the N-acetyl-2,3-dehydro-aminocarboxylic acid ester of general formula (I) formed, it is suitable to carry out the reaction in the presence of a known inhibitor for radical polymerization, such as hydroquinone or hydroquinone monomethyl ether. The inhibitor can be employed in an amount of 0.001 to 10 weight percent, especially 0.1 to 2.5 weight percent, based on the 2-azido-carboxylic acid ester of general formula (II) employed.
The mixture of one part by volume of acetic anhydride and 1.5 to 5 parts by volume of acetic acid serving as acetylation agent is suitably used in an amount of 260 to 5000 ml, preferably 500 to 3000 ml per mole of 2-azido-carboxylic acid ester of general formula (II) employed.
The process of the invention for example can be carried out in such manner that a mixture of acetic anhydride and acetic acid with the rhenium VII sulfide and/or oxide and, in a given case, the polymerization inhibitor is present and with vigorous stirring the 2-azido-carboxylic acid ester of the general formula (II) which is to be reacted is fed in slowly, e.g. in the course of two hours. It is recommended to maintain the reaction mixture at the reaction temperature after the end of the development of nitrogen for a longer period of time, for example 20 hours.
A considerable shortening of the required reaction time can be attained in many cases if the reaction is undertaken in the simultaneous presence of dry hydrogen chloride. In this case, it is advantageous to dissolve the 2-azido-carboxylic acid ester of general formula (II) which is to be reacted in the mixture of acetic anhydride and acetic acid, to add the rhenium VII sulfide and/or oxide and, in a given case, the polymerization inhibitor and then to lead in dry hydrogen chloride up to saturation. Then the mixture is subsequently heated to the reaction temperature. Generally in this method of operation a reaction time of at most 3 hours is sufficient.
After the end of the reaction the acetic acid and the excess acetic anhydride are removed, suitably under reduced pressure, for example, in a rotary evaporator. The residue is taken up in a readily volatile solvent, for example, diethyl ether, the solution filtered and the filtrate evaporated under reduced pressure. For further purification the residue is then chromatographed over a silica gel column with a mixture of low boiling petroleum ether and ethyl acetate (volume ratio about 2:1) as the mobile phase. After evaporation of the eluate, suitably again under reduced pressure, there remains behind the practically analytically pure N-acetyl-2,3-dehydro-aminocarboxylic acid of general formula (I).
Then by asymmetrical catalytic hydrogenation in known manner at will, there can be produced the corresponding L- or D-N-acetyl-aminocarboxylic acid esters from the N-acetyl-2,3-dehydro-aminocarboxylic acid esters, and the L- or D-N-acetyl-aminocarboxylic acid esters saponified to the corresponding L- or D-2-aminocarboxylic acids.
Unless otherwise indicated all parts and percentages are by weight.
The process can comprise, consist essentially of, or consist of the stated steps with the materials set forth.
The invention will be explained further through the following examples.
DETAILED DESCRIPTION
Example 1
0.925 gram (1.55 mmoles) of rhenium VII sulfide and 0.5 gram of hydroquinone were dissolved in a mixture of 120 ml of acetic anhydride and 280 ml of acetic acid. Then at 80° C. within 2 hours under vigorous stirring there were dropped in 20.0 grams (0.155 mole) of 2-azido-propionic acid methyl ester.
The reaction proceeded with uniform development of nitrogen. After the end of the development of gas the mixture was allowed to further react for 20 hours at 80° C. and then the acetic acid and the excess acetic anhydride removed under reduced pressure. The residue was taken up in 100 ml of diethyl ether, the solution filtered, the filtrate evaporated and the residue chromatographed over a 20 cm high silica gel column with a mixture of low boiling petroleum ether and ethyl acetate in a volume ratio of 2:1 as mobile phase.
After the evaporation of the eluate there are obtained 15.7 grams (71% of theory) of analytically pure N-acetyl-2,3-dehydroalanine methyl ester, ##STR3## having a melting point of 52° C. (literature 52°-54° C.).
Example 2
1.0 gram (5.84 mmole) of 2-azido-hexanoic acid methyl ester was dissolved in a mixture of 2 ml of acetic anhydride and 3 ml of acetic acid and treated with 5 mg of hydroquinone and 35 mg of rhenium VII sulfide. Then the solution was saturated with dry hydrogen chloride.
The reaction mixture was held for 2 hours at 80° C. under vigorous stirring and subsequently the product worked up in a manner analogous to Example 1. There were obtained 0.98 gram (91% of theory) of analytically pure N-acetyl-2,3-dehydro-norleucine methyl ester having a melting point of 49°-51° C.
______________________________________C.sub.9 H.sub.15 NO.sub.3 (185, 22) C H N______________________________________Calculated: 58.36% 8.16% 7.56%Found: 58.18% 8.25% 7.48%______________________________________.sup.1 H--NMR (CDCl.sub.3):δ = 7.5 (s,1H) NH; 7.0 (t,1H) CH; 3.83 (s,3H) COOCH.sub.3 ; 2.52 (q,2H) CH.sub.2 --CH═; 2.08 (s,3H) N--COCH.sub.3 ; 1.49 (m,2H) CH.sub.3 --CH.sub.2 --CH.sub.2 ; 0.94 ppm (t,3H) CH.sub.3 --CH.sub.2.______________________________________
Example 3
1.0 gram (4.56 mmole) of 2-azido-3-phenylpropionic acid ethyl ester was dissolved in a mixture of 1 ml of acetic anhydride and 4 ml of acetic acid and treated with 5 mg of hydroquinone and 27 mg of rhenium VII sulfide. Then the solution was saturated with dry halogen chloride.
The reaction mixture was held under vigorous stirring for 2.5 hours at 80° C. and subsequently worked up analogous to Example 1. There were obtained 0.96 grams (90% of theory) of analytically pure N-acetyl-2,3-dehydro-phenyl-alanine ethyl ester ##STR4## having a melting point of 96°-97.5° C. (literature 96°-98° C.).
______________________________________C.sub.13 H.sub.15 NO.sub.3 (233, 267) C H H______________________________________Calculated: 66.94% 6.48% 6.01%Found: 66.77% 6.62% 5.72%______________________________________.sup.1 H--NMR (CDCl.sub.3):δ = 9.0 (s,1H) NH; 7.30-7,75 (m,5H) arom.-CH═; 4.26 (q,2H) COOCH.sub.2 ; 1.32 (t,3H) COOCH.sub.2 --CH.sub.3 ; 2.06 ppm (s,3H) CO--CH.sub.3.______________________________________
Example 4
1.0 gram (6.36 mmole) of 2-azido-3-methylbutyric acid methyl ester was dissolved in a mixture of 2 ml of acetic anhydride and 4 ml of acetic acid and treated with 5 mg of hydroquinone and 38 mg of rhenium VII sulfide. Then the solution was saturated with dry hydrogen chloride.
The reaction mixture was held at 80° C. with vigorous stirring for 2 hours and subsequently worked up analogous to Example 1. There was obtained 0.98 gram (90% of theory) of analytically pure N-acetyl-2,3-dehydrovaline methyl ester. ##STR5## having a melting point of 93°-94° C. (Literature: 88°-89° C.).
______________________________________C.sub.8 H.sub.13 NO.sub.3 (171,196) C H N______________________________________Calculated: 56.13% 7.65% 8.18%Found: 56.10% 7.56% 8.28%______________________________________.sup.1 H--NMR (CDCl.sub.3):δ = 7.55 (s,1H) NH; 3.72 (s,3H) COOCH.sub.3 ; ##STR6## 2.06 (s,3H) COCH.sub.3 ; ##STR7##______________________________________
Example 5
1.0 gram (6.36 mmole) of 2-azido-3-methylbutyric acid methyl ester was dissolved in a mixture of 2 ml of acetic anhydride and 3 ml of acetic acid and treated with 10 mg of hydroquinone and 15.4 mg of rhenium VII oxide. Then the solution was saturated with dry hydrogen chloride.
The reaction mixture was held at 80° C. with vigorous stirring for two hours and subsequently worked up analogous to Example 1. There was obtained 0.97 gram (89% of theory) of analytically pure N-acetyl-2,3-dehydro-valine methyl ester.
Example 6
1.0 gram (6.36 mmole) of 2azido-3-methylbutyric acid methyl ester was dissolved in a mixture of 2 ml of acetic anhydride and 3 ml of acetic acid and treated with 10 mg of hydroquinone and 1.5 mg of rhenium VII oxide. Then the solution was saturated with dry hydrogen chloride.
The reaction mixture was held at 80° C. under vigorous stirring for 2 hours and subsequently worked up analogous to Example 1. There were obtained 0.97 gram (89% of theory) of analytically pure N-acetyl-2,3-dehydro-valine methyl ester.
Example 7
1.0 gram (4.21 mmole) of 2-azido-3-phenylmercapto-propionic acid methyl ester was dissolved in a mixture of 1.5 ml of acetic anhydride and 3.5 ml of acetic acid and treated with 5 mg of hydroquinone and 25 mg of rhenium VII sulfide. Then the solution was saturated with dry hydrogen chloride.
The reaction mixture was held at 85° C. with vigorous stirring for 3 hours and subsequently worked up analogous to Example 1. There was obtained 0.82 gram (77% of theory) of N-acetyl-3-phenylmercapto-2,3-dehydro-alanine methyl ester. ##STR8## having a melting point of 103°-105° C.
______________________________________C.sub.12 H.sub.13 NO.sub.3 S (251,304) C H N S______________________________________Calculated: 57.35% 5.21% 5.57% 12.76%Found: 57.19% 5.22% 5.66% 12.90%______________________________________.sup.1 H--NMR (CDCl.sub.3):δ = 8.06 (s,1H) NH; 7.2-7,6 (m,5H) arom.-CH═; 7.66 (s,1H) S--CH═; 3.78 (s,3H) COOCH.sub.3 ; 2.18 ppm (s,3H) CO--CH.sub.3.______________________________________
The entire disclosure of German priority application No. P 3140227.5 is hereby incorporated by reference. | The subject matter of the invention is a process for the production of N-acetyl-2,3-dehydroaminocarboxylic acid esters by reaction of the corresponding 2-azido-carboxylic acid esters with a mixture of one part by volume of acetic anhydride and 1.5 to 5 parts by volume of acetic acid in the presence of rhenium VII sulfide and/or oxide and at a temperature between 50° and 150° C., in a given case, in the simultaneous presence of dry hydrogen chloride. | 2 |
FIELD OF THE INVENTION
The invention relates to a method for attaching parts to elongated writing instruments, in particular for securing an eraser and/or a sheath receiving the eraser on a pencil, wherein the pencils are guided parallel to and equidistant from one another through a work station in which processing or attaching tools move along in alignment with the pencils, and to an apparatus for performing this method.
BACKGROUND OF THE INVENTION
Securing cylindrical erasers to one end of a pencil using a metal sheath has been known for many years. The usual method involves pushing the sheath onto the pencil from its conically tapered end and then, after the insertion of the eraser into the sheath, radially deforming the sheath, with these operations taking place sequentially.
In the apparatus described by German laid-open application DE-OS No. 23 56 071, the individual production steps were successfully united into a continuous operation. However, the transport drums for the pencils provided in that apparatus necessitate a relatively expensive holder for the drums, and the distance between the individual pencils has to be relatively great, because one individual processing tool is assigned to each individual pencil. The processing speed thereby attainable is accordingly not yet satisfactory.
SUMMARY OF THE INVENTION
It is accordingly the principal object of the invention to provide a method, and apparatus for performing the method, of the general type described above which is highly reliable in operation, and which facilitates a high operating speed.
This object is attainable by including the steps of attaching a sheath or inserting an eraser, which themselves are discontinuous in nature, into a continuous operation by providing that a feeder device moves along with the pencils being conveyed by a transporting device while the operation is being performed, and that the sheaths be attached simultaneously to a plurality of pencils. The time elapsing during the rapid return travel of the feeder device does not have the effect of an interruption of the operation, because new sheaths or erasers are delivered during the entire time.
Another object of the present invention is that the method be performed such that two, three or four pencils are processed at a time, thus producing a particularly favorable ratio between the mass of the parts of the feeder device which are being moved and the travel speed of the pencils being advanced within the work station.
Still another object of the invention is to incorporate the process of tapering, which is a preparatory step for the actual process of attachment, into the continuous operation as well.
Yet another object is to provide a cam drive for coordinating movement of the feeder device with the drive of the transporting device.
Other objects of the invention include:
(1) providing a tapering device movable in a coordinated manner with the drive of the transporting device, so that the pencils are provided with a slightly conical shape on one end whereby a self-centering effect is attained during the subsequent attachment of the sheaths, and firm clamping of the sheath occurs under the influence of an applied axial pressure;
(2) providing that the tapering device have a conical shaping recess to counteract any seizing that might otherwise occur as the tapering tool is retracted after the tapering has been effected;
(3) providing means for preventing the pencils from sticking to the tapering device;
(4) providing only a single conveyance route so that the entire assembly process can take place without any preliminary assembly or intervention from outside;
(5) providing a gluing station so that a supplemental hold on the sheaths is attained;
(6) providing a stop device for the transporting device so that the pencils being moved forward are fixed in the axial direction;
(7) providing that the pencils be prevented from tilting out of alignment due to friction with the stop device as pressure is applied while the pencils simultaneously continue to be transported;
(8) providing that, when the sheaths and the erasers are attached, the pencils be delivered in a precisely defined position;
(9) providing that the pressing mechanism of the feeder device includes recesses having cylindrical shape which facilitate the alignment of the sheaths or erasers with the pencils;
(10) providing that the base body of the feeder device be driven, reciprocably, in a direction normal to the conveyance direction thereby attaining coordination of movement between the transporting movement and the reciprocating movement of the base of the feeder device;
(11) providing one position of the feeder device in which the outlet openings of the feeder lines are blocked;
(12) providing means for refilling the feeder receses when the feeder device is making its return trip, so that a substantial increase in the operating speed can be attained, and
(13) providing a reliable guidance system for the movement of the feeder device.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics, advantages and details of the invention will become apparent from the following description of a preferred form of embodiment, when taken in conjunction with the drawings, in which:
FIG. 1 is a schematic top view of an apparatus according to the invention;
FIG. 2 is a schematic longitudinal section taken through an apparatus according to the invention;
FIG. 3 is a cross section taken along the line III--III of FIG. 1;
FIG. 4 is a partial section taken through the base body and the rack part of the feeder device;
FIG. 5 is a top view of the assembly shown in FIG. 4;
FIG. 6 is a section taken at right angles to the transporting device, and corresponds to the assembly shown in FIGS. 4 and 5; and
FIG. 7 is a diagram showing the routes traveled by the individual parts during one operating cycle.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The apparatus according to the invention and its mode of operation will now be described in terms of the attachment of sheaths and erasers onto pencils. The invention however, is not restricted to pencils, and can instead be applied in like manner to similar writing instruments, and parts which are to be attached thereto.
In FIG. 1, a conveyor belt 1 is shown which travels around deflection rollers 2, 3. The direction of conveyance in the work station is indicated by the arrow 4. The conveyor belt 1 is driven via a worm 5 located on a main drive shaft 6, the latter being driven by a motor (not shown). In an exemplary embodiment, rotational drive of the sprocket 2 may occur at the end of the conveyance route if the conveyor belt 1 is embodied as a high-grade steel band. However, it can be effected at the deflecting roller 3, also embodied as a sprocket, and as such may be advantageous if the conveyor belt 1 is embodied as a pushed (instead of pulled) chain, so as to avoid having spaces between the individual links of the chain conveyor 1.
On one side of the conveyor belt 1 (at the bottom in FIG. 1), a stop device or assembly 7 is provided. It includes a strip 8, which is movable back and forth in a plane at right angles to the plane in which the conveyor belt 1 moves, in synchronism with a work plate 20 to be described later. A guide means for the strip 8 is provided by rollers 9. the drive connection 10 is shown only schematically.
As may be seen in FIG. 2, a guide plate 12 is provided beneath the upper segment of the conveyor belt 1. Recesses 13 are provided at regular intervals on the conveyor belt 1, disposed parallel to one another and at right angles to the conveyance direction 4 of conveyor belt 1; each recess 13 is capable of receiving one pencil 14.
The frame 15 which supports the apparatus according to the present invention is provided on the side opposite the stop assembly 7. A tapering device 16, a feeder device 17 for the sheaths and a feeder device 18 for the erasers are provided sequentially, one next to the other on the frame 15. The three devices are located on a common work plate 20 which is movable back and forth in the conveyance direction 4 via a sled guide 19. A gluing station may also be disposed between the feeder devices 17 and 18.
The movement of the work plate 20 is controlled via a control cam cylinder 21 seated on the main drive shaft 6. The movement of opposing sides of control cam cylinder 21 is scanned or followed by (i.e. transmitted to) the rollers 22, 23, which are secured on the work plate 20, and the control cam cylinder 21 is shaped such that (1) the work plate 20 moves parallel to the conveyor belt 1 in the conveyance direction 4 during a first movement phase, with the major portion of this movement taking place at the speed of the conveyor belt 1, and (2) the work plate 20 executes a backward movement counter to the conveyance direction during a second movement phase. The speed of the backward movement is substantially greater than the conveyance speed; this second phase is accordingly substantially shorter in duration than the first phase.
The tapering device 16 and the feeder devices 17, 18 each have respective base bodies 24, 25 and 26, which are in turn movable back and forth at right angles to the conveyance direction 4, relative to the work plate 20 and to the conveyor belt 1, via respective sled guides 27, 28 and 29. The drive of the reciprocating movement of the base bodies 24, 25, 26 is derived from the main drive shaft 6 via respective cam drives 30, 31, 32. Cam cylinders which are scanned on both sides are preferably used as the cam drives 30-32, because good compulsory guidance is thereby attained. In the exemplary embodiment, cam discs are shown as the cam drives.
In FIG. 3, the cam drive 31 for the base body 25 of the feeder device for the sheaths is shown, with the cam drives 30 and 32 being practically identical in design. The control disc of the cam drive 31 is seated on the main drive shaft 6 and turns in the direction of the arrow 33. The movement of the cam disc of the cam drive 31 is scanned or followed by a roller 34, which is seated on the transmission linkage 35 and is pressed by the force of the spring 36 against the cam disc. The transmission linkage 35 substantially comprises four linkage elements 37-40, with the linkage elements 37 and 39 being approximately vertical and the linkage elements 38 and 40 being approximately horizontal. The linkage element 37 is supported with its lower end on the stationary joint 41 on the frame 15. At its upper end, linkage element 37 carries the roller 34. From there, the linkage element 38 leads to the free deflecting joint 42, which interconnects the linkage elements 38 and 39. The linkage element 39 is pivotably disposed approximately at its center via the vearing 42' connected in a stationary manner via work plate 20 with the base body 25. At the end of the linkage element 39, a joint 43 is provided which is interconnected with the approximately horizontal linkage element 40. Joint 43 permits movement about both an axis parallel to the conveyance direction 4 and an axis at right angles to the plane of the work plate 20. The linkage element 40 is connected with the base body 25 via a joint (not shown in detail), which permits a movement about a plane at right angles to the work plate 20.
The drive of the tapering device 16 is similar in design to that of the feeder devices 17, 18. However, the linkage element 44 corresponding to the linkage element 40 terminates at a force-transmitting frame 50. The force-transmitting frame 50 has two longitudinal struts 51 disposed parallel to and spaced apart from one another, which are guided on the work plate 20 at 52 and which carry the base body 24 of the tapering device 16 on their ends remote from the linkage 44. Trumpet-shaped recesses 53 for tapering the pencils 14 are disposed on the base body 24, spaced apart by a distance A, as may be seen from the partially cutaway view of FIG. 1. Each such recess 53 is aligned with a corresponding stripping-off device 54 shown only schematically. These stripping-off devices are placed such that upon the return travel of the base body following the tapering process, any pencils 14 which may stick to it are held in their places. This result is attained by providing that the stripping-off devices 54 be secured on a common cross-strip 45 engaged by a cam disc 46 driven via a gear rack (not shown in detail). In this way, the stripping-off devices 54 are deflected relative to the longitudinal struts 51 such that during the return travel of the tapering device 16 they rest against the end faces of the pencils 14.
The feeder devices 17 and 18 are substantially identical in design, so that their design will be described here substantially in terms of the feeder device 17 for the sheaths. As already described, the feeder device 17, 18 have respective base bodies 25 and 26, which are disposed on respective sled guides 28 and 29. The embodiment of these sled guides 28, 29 is apparent in FIG. 1 from the partially cutaway guide 29, which includes guide sleeves 55 and guide rods 56. Feeder recesses 57 in the form of cylindrical segments are disposed in the base body 25, and their radius of curvature is approximately equal to that of the sheaths which are to be received there, so that these sheaths are held in a definite position. The recesses 57 are open toward the top and are closed at the back by the rear wall 57'. In the exemplary embodiment, the number n of feeder recesses 57 is four. The spacing between the feeder recesses 57, which are parallel to one another and disposed equidistant from one another, equals the distance A between the recesses 13 for the pencils 14 on the conveyor belt 1.
As seen particularly well in FIGS. 3 and 6, a number of feeder lines 58 equal to the number of recesses 57 discharge from above the base body. The outlet openings 59 of the feeder lines 58 are disposed such that each is disposed in the vicinity of the space between the feeder recesses 57.
Above the base body 25 and forwardly of the openings 59, a rack element 60 is provided, supported on the base body 25 such that it can be slidingly reciprocated in the conveyance direction 4. The rack element 60 includes recesses 61 corresponding to the recesses 57 on the base body 25; in cross section, the recesses 61 are rectangular, and they are open toward the base body 25 (i.e. downwardly open) and closed toward the conveyor belt 1 (i.e. forwardly closed). Prongs 62 are formed between, and by means of, the recesses 61. In a first position of the rack element 60, prongs 62 are located in front of the outlet openings 59 of the feeder lines 58, thus blocking these lines. In this position, the recesses 61 coincide with the feeder recesses 57 of the base body. In a second position of the rack element 60, recesses 61 are located in front of the outlet openings 59 of the feeder lines 58. This position is shown in FIGS. 4, 5 and 6.
The actuation of the rack element 60 is effected via cam drives 63-65, which are schematically shown in FIG. 2. In FIG. 1, the cam drive 65 for the feeder device 18 and the transmission linkage 66 are shown in greater detail. The corresponding elements are provided in identical form for the feeder device 17. The cam drive 65 is scanned or followed by a roller 67, which is supported at the end of a linkage element 68. The middle of the linkage element 68 is supported on a stationary joint 69, which is connected to the frame 15. The other end of the linkage element 68 acts via crank (now shown in detail) supported on the work plate 20 such that it is pivotable about an axis perpendicular to the work plate 20, and the other arm of the crank is connected in turn with the guide rod 70 of the rack element 60. The guide rod 70 is supported in guide sleeves (not shown) in such a manner that it is movable back and forth in the conveyance direction 4 together with the rack element 60. The roller 67 is made to contact the cam drive 65 by means of a spring mechanism (not shown in detail). However, the cam drive 65 may also be embodied as a cam cylinder, which is scanned or followed on both sides, so that a compulsory guidance is attained.
The mode of operation of the apparatus according to the invention, and thus the method according to the invention as well, will now be described:
The drive wheels 71 seated on the main drive shaft 6 are driven thereby, and thus drive the entire drive mechanism derived therefrom. Via a supply and feeder device 72, pencils 14 are placed onto the conveyor belt 1 individually, one after another, and thereafter drop into the recesses 13 so that they are moved in the conveyance direction 4. Just as a set of four pencils 14 (to distinguish the sets from one another visually in FIG. 1, they are shown alternatively in dashed and solid lines) reaches the area immediately before the tapering device 16, the tapering device is driven in such a way that for a certain, predetermined distance along the conveyance route it travels alongside the set of pencils at the same speed. The base body 24 is moved toward the pencils 14 and effects a conical tapering of the ends of the pencils adjacent thereto via the recesses 53. The base body 24 of the tapering device 16 is then moved back again, during the course of which the pencils 14 are held in their position by the stripping-off device 54. The tapering device 16 then returns, at high speed, to its starting position.
At the onset of a new work cycle, the set of pencils reaches the areas immediately before the feeder device 17 for the sheaths, which now likewise travels along parallel to the set of pencils. During this process, one sheath is located in each recess 57 of the base body 25, and as a result of simultaneous movement of the base body 25 to the conveyance direction 4 toward conveyor 1, the sheaths are moved toward the pencils and pushed onto them. Because of the conical tapering of the pencils 14, a self-centering effect is attained, as well as a simultaneous clamping seat of the sheaths on the pencils. The pressing of the sheaths onto the pencils is facilitated by the abutment of the rear side of the sheaths against the rear wall 58 of their respective recesses 57, and the remote end of the pencils resting on the strip 8 of the stop device 7. After the sheaths have been put into place, the base body 25 moves back away from the pencils 14 and is returned back to its starting position by the backward movement of the work plate 20 parallel to the conveyance direction 4. At the beginning of this return movement, the rack element 60 is deflected out of the position shown in FIGS. 4, 5 and 6, so that the sheaths can drop into the now-empty recesses 57 of the base body 25. The rack element then returns back to its starting, recess covering position, and the outlet openings 59 of the feeder lines 58, which are connected with a supply magazine are then uncovered so that new sheaths can be supplied to the recesses 61 of the rack element 60. This situation is illustrated in FIG. 4 for cylindrical bodies 73 which may be either erasers or sheaths.
As a result of the operation of the apparatus, as described above, simultaneous emplacement of a plurality of sheaths (in this case, four) is advantageously attained; time for the return travel of the feeder device, ordinarily lost, is thereby saved so that a work step which by itself is discontinuous can be incorporated into a continuous process. Thus by controlling movements of the rack element, time required for the return movements of the feeder device 17 can be utilized for refilling purposes.
As the pencils 14 continue to travel in the conveyance direction 4, they reach the vicinity of the feeder device 18 for the erasers. The insertion of the erasers into the sheaths is effected in a completely analogous manner to the placement of the sheaths on the pencils. The sheaths merely need to be dimensioned such that a secure clamping seat is attained as a result of the axial pressure exerted.
After the pencils have traveled through the work stations, they are removed from conveyor belt 1 by means of a removing device 74, such as that described in detail in German Patent Application No. P 31 47 863.8.
In order to illustrate in detail the course of movement of the individual elements, the routes traveled are plotted in FIG. 7 in accordance with the time required for completing each complete work cycle. Each work cycle can be divided into two phases, T 1 and T 2 , which correspond to the periods required for the forward, and the backward, movement, respectively, of the work plate 20.
FIG. 7(a) shows how the rack element 60 of the feeder devices 17 and 18 is brought, at the end of the forward-travel phase T 1 , into the position where the outlet openings 59 of the feeder lines 58 are blocked by the prongs 62 of the rack element 60 and sheaths or erasers are inserted into the recesses 57. At the onset of the new work phase, the rack element 60 is then displaced such that the outlet openings 59 are uncovered, so that a new set of sheaths can be supplied. The deflection of the rack element 60 then amounts to approximately half the distance A, or A/2. The movement of the rack element 60 is effected parallel to the conveyance direction 4.
In FIG. 7(b), the travel of the base body 25 (or 26) of the feeder device 17 (or 18) is shown. It can be seen that the process of placing the sheaths on the pencils (or the erasers into the sheaths) takes place during the forward-movement phase, wherein the base body 25 or 26 moves to and fro at right angles to the conveyance direction 4, toward and away from the pencils 14 being transported along the conveyor belt 1. The deflection path of the feeder device 17 for the sheaths has to be somewhat greater in dimension in quantitative terms than that of the feeder device 18 for the erasers, because the sheaths have to be pushed onto the pencils to greater depth than the erasers have to be pushed in being inserted into the sheaths.
FIG. 7(c) shows the travel of the work plate 20 parallel to the conveyance direction 4 and beside it the travel of the base bodies 25, 26. The axis for the travel of the work plate 20 in the graph serves as the axis for the time of the movement of the base bodies. The drawing shows that, as described above, the work plate moves in the conveyance direction 4 during a first phase T 1 and is then moved back counter to the conveyance direction 4, during a second phase T 2 , which is shorter than T 1 . During the forward movement, the base body 25 or 26 performs the movement for placement or insertion of the sheaths or erasers, while during the return movement it is relocated in its starting position. | In a method intended particularly for securing an eraser and/or a sheath eiving it on a pencil in one continuous operation, it is provided that the pencils are conveyed through a work station and during that time, several sheaths or erasers and associated tools are simultaneously moved along with the pencils at the same speed as the pencils during a first work phase and are attached to the pencils during this time via the tools; in a second work phase, after the attachment process is completed, the tools are returned rapidly to the outset point, counter to the conveyance direction. The invention is furthermore directed to an apparatus for performing this method, which assures a very high operating speed. This apparatus includes at least one feeder device connected with a supply magazine for supplying one eraser or sheath to each of n feeder recesses having closed rear sides and being disposed beside one another in the feeder device. The feeder device is coupled via a cam drive with the drive mechanism of the transporting device in such a manner that the method step provided in accordance with the intention can in fact be performed. | 8 |
RELATED APPLICATION
This application is a continuation-in-part of my application entitled Tobacco Extract Composition and Method, Ser. No. 08/349,966, filed Dec. 6, 1994, now U.S. Pat. No. 5,435,941, which is a continuation-in-part of my application entitled TOBACCO EXTRACT COMPOSITION AND METHOD, Ser. No. 08/169,777, filed Dec. 17, 1993, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a composition and methods for production and use of industrial chemicals extracted from biomass, and more specifically, to a tobacco extract for corrosion inhibition treatment of metallic surfaces.
2. Description of the Prior Art
Corrosion is defined as the loss of the essential metallic properties of a metal. Corrosion consumes increasingly scarce raw materials and wastes the energy expended in the extraction and refining of metals as well as that involved in manufacturing components and structures. Since corrosion affects virtually every aspect of modern civilization, corrosion prevention is of major economic and environmental importance.
One approach to corrosion control is to add an inhibitor to the system. One way an inhibitor works is that it reacts with the metal to form a protective surface film. Typical examples are the inhibitors added to automobile cooling systems and corrosion-inhibiting pigments in protective paints for metals. However, many corrosion inhibitors in current use are toxic and/or have an adverse effect on the environment. There is increasing legislative pressure for the elimination of heavy metal compounds and toxic organic and inorganic corrosion inhibitors such that the development of effective and environmentally-friendly inhibitors is of major importance.
There have been few advances in the development of novel and effective corrosion inhibitors in recent years, while at the same time, there is a legislation-driven trend to eliminate many of the inhibitors in common use. Thus, inhibitors based on heavy metals, e.g., lead compounds, chromates, and those containing a variety of toxic anions, e.g., nitrites, phosphates and benzoates, are no longer acceptable. Consequently, a high proportion of corrosion inhibitors currently used in chemical industry, paint technology, metal finishing, cooling systems, and so forth require replacement by environmentally-acceptable substances. There is, however, little information on environmentally-acceptable corrosion inhibitors.
SUMMARY OF THE INVENTION
Tobacco products contain high concentrations of alkaloids, fatty acids and N-containing compounds, many of which inhibit metallic corrosion. Compounds leached from tobacco with water have the ability to inhibit metallic corrosion. In particular, tobacco extracts inhibit the galvanic corrosion of steel when coupled to copper in a sodium chloride solution, a solution known to rapidly corrode iron and steel. In fact, tobacco extracts appear to be more effective in inhibiting corrosion than the well known inhibitor, potassium chromate, under the same conditions.
There are numerous advantages of using tobacco extract as a metallic corrosion inhibitor. Initially, tobacco is a natural, renewable, environmentally benign, and relatively inexpensive source. In addition to leaves, tobacco waste (stems, twigs, etc.) can be used for corrosion inhibitor extraction. The active constituents (metallic corrosion inhibitors) in tobacco can be readily, inexpensively, and commercially extracted in a simple operation using only water as an extraction medium. In addition, the corrosion inhibitors in tobacco constituents can be extracted in a variety of additional or alternative media, as in steam, organic solvents, acids, etc. Treating metals and metallic surfaces with the extracted corrosion inhibitors can be effected by a number of currently used commercial methods, as in by dip or spray coating, electrostatic coating, or by formulating the corrosion inhibitors with paint or other coatings to be applied to the metallic surfaces in conventional commercial methods.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a listing of Type A and Type B corrosion inhibitors.
FIG. 2 is a table of the average concentrations in dry tobacco leaves of electrochemically active compounds.
FIG. 3 is a current density/time relationship graph of a copper-steel galvanic couple in solutions of saline, saline and potassium chromate, and saline and tobacco extract.
FIG. 4 is a current density/time relationship graph of a steel-platinum galvanic couple in solutions of saline, saline and potassium chromate, saline and chewing tobacco extract, and saline and pipe tobacco extract.
FIG. 5 is a current density/time relationship graph of a brass-platinum galvanic couple in solutions of saline, saline and potassium chromate, saline and chewing tobacco extract, and saline and pipe tobacco extract.
FIG. 6 is a current density/time relationship graph of a aluminum-platinum galvanic couple in solutions of saline, saline and potassium chromate, saline and chewing tobacco extract, and saline and pipe tobacco extract.
FIG. 7 is a current density/time relationship graph of a steel-brass galvanic couple in solutions of saline, saline and potassium chromate, saline and chewing tobacco extract, and saline and pipe tobacco extract.
FIG. 8 is a current density/time relationship graph of a steel-aluminum galvanic couple in solutions of saline, saline and potassium chromate, saline and chewing tobacco extract, and saline and pipe tobacco extract.
FIG. 9 is a current density/time relationship graph of a aluminum-brass galvanic couple in solutions of saline, saline and potassium chromate, saline and chewing tobacco extract, and saline and pipe tobacco extract.
FIG. 10 is metal loss/time graph showing the surface loss of mild steel in a 10% sulfuric acid solution and a 5% tobacco extract concentration added to the 10% acid solution.
DETAILED DESCRIPTION OF THE INVENTION
Virtually all metals and alloys are subject to corrosion. One of the most common examples is surface discoloration, e.g., tarnish of silver or rusting of steel. Metal destruction by corrosion occurs through loss of metal ions directly into solution or by progressive dissolution of a surface film, typically an oxide or sulfide compound of the metal. Uniform attack is less destructive than localized or pitting attack, and the latter may cause catastrophic failure of structures or engineering components when there is progressive corrosion within the bulk of the metal.
Very few metals, e.g., gold and platinum, are inert, and most others rely upon an oxide film for their resistance to corrosion. Disruption of the protective film or the presence of a medium that causes dissolution of the film and prevents its re-formation will result in corrosion. Even in the absence of disruptive effects such as abrasion or scratching, oxide films often slowly dissolve or fall away from the metal surface, and then reform as the exposed metal surface is exposed to air or oxygen from its surrounding medium.
Corrosion is an electrochemical process, that is, there is passage of an electric current and movement of ions or electroactive species through solution followed by reaction at electrodes. Corrosion, therefore, results in the consumption of metals through reaction with their environment. Inhibition (prevention) of corrosion therefore involves transport of appropriate electroactive species through solution to the reacting metal surface, the electrode, where there is interaction with the metal surface and a reduction in the rate of metal dissolution. The deleterious effects of corrosion range from the unsightly tarnishing of silver, to the expensive rusting of automobiles, to a wide variety of allergic reactions from metals, to the almost incalculable costs of structural failures that result in loss of production and loss of life. Accordingly, corrosion prevention is of major importance. Four principal approaches are used in its prevention, namely, materials selection, surface coatings, anodic or cathodic protection, and environment modification.
Corrosion involves two concomitant reactions, an oxidation reaction at the anode and a reduction reaction at the cathode. In the case of zinc corroding in dilute acid, these reactions are:
Anode: Zn→Zn 2+ +2e
Cathode: 2H + +2e→H 2
These two reactions proceed at equal and opposite rates. In neutral and high pH media, the predominant cathodic reaction is reduction of oxygen to hydroxyl ions.
In most corrosion processes, the anodic reaction will continue until there is total consumption of the metal, unless (1) the metal can form a protective surface film (“passivation”), (2) the cathodic reactant is consumed (e.g., exhaustion without replenishment of dissolved oxygen in solution), or (3) the corrosion process is inhibited by additives to the medium. Depending upon the thermodynamics and kinetics of the overall reaction, corrosion may proceed slowly or rapidly, and occur as a general or localized attack. It is common, for example, that a pure metal may resist attack by a given reagent but will corrode quite rapidly when it contains impurities that facilitate an otherwise thermodynamically and/or kinetically unfavorable reaction. Similar effects occur if the medium contains a more readily reducible cathodic reactant than oxygen. For example, the atmospheric pollutant SO2 is some 1600 times more soluble in water than is oxygen (O 2 ), and is more readily reduced so that corrosion of steel occurs far more rapidly in urban (polluted) atmospheres than in rural areas.
When two metals are connected together in an electrolyte or conducting solution, the more electronegative metal will become the anode and corrode, while the more electropositive metal functions as the cathode. This form of corrosion cell is known as a galvanic cell or galvanic couple. This is the basis for the well-known protection of iron by galvanizing or zinc coating, where the zinc corrodes preferentially to the iron and is termed a sacrificial anode. Similar principles are utilized for the protection of underground pipelines, offshore oil rigs, shipping, etc.
Galvanic corrosion is common and numerous examples are known. Galvanic couples may be set up on areas of passivated (oxide coated) metals at breaks in the oxide layers or at perforations (“holidays”) in protective coatings. Further, corrosion may be accelerated when a galvanic cell is established such that there is stimulation of the corrosion rate of a corrosion-resistant metal or of a metal that exhibits a low corrosion rate only in the absence of such cells. Galvanic couples may be established under a number of different circumstances. In all cases, differences in electrochemical potential between two metals or at different sites on the same metal will cause the creation of galvanic cells which result in corrosion.
The effects of galvanic corrosion vary with the nature and type of the individual galvanic cell. Extensive literature exists on corrosion and galvanic corrosion cells. One of the most common examples of galvanic corrosion is that occurring in the cooling system of automobile engines due to the presence of a variety of metals, typically cast iron, mild steel, copper and aluminum, as well as soldered and welded joints within the cooling system itself. In addition, ethylene glycol anti-freeze is very corrosive towards metals. Necessarily, therefore, all cooling systems require some form of corrosion inhibition, typically a benzoate-nitrite mixture.
Appropriate selection of materials may prevent, or at least significantly reduce, many corrosion problems, but considerations of cost, manufacturing methods, service requirements and conditions often dictate the choice of materials. Surface coatings, typically electrodeposited metals, galvanizing, polymeric coatings and paints, are used to provide corrosion protection, often through a barrier effect. Anodic or cathodic protection methods, typically sacrificial anodes or impressed current systems, are widely used for large structures such as buried pipelines, oil drilling rigs, ships and within chemical plants, and are very effective. Finally, when corrosion cannot be controlled by other means, modification of the environment may be required.
Environment modification involves either removal of corrosive agents or the addition of inhibitors, compounds that react with the metal to form a protective surface film or which remove or react with corrosive agents. Corrosion control in automotive cooling systems relies on inhibitors, typically a combination of sodium benzoate and sodium nitrite, added to protect the multi-component cooling system from corrosion by ethylene glycol antifreeze.
A combination of barrier action and inhibition occurs with protective paint coatings which contain leachable inhibitors that are transported to the metal substrate surface with ingress of fluids, and provide protection at the possible sites of attack. Protective paint coatings are a major method of protecting structures against corrosion, and they have the great advantage that they can be “tailored” to specific requirements and applications.
The selection of corrosion inhibitors used in industry and as pigments in protective paints, however, has been markedly affected by two legislation-driven developments, notably, the elimination of heavy metals and their compounds, and the impetus to use water-borne paints in place of organic solvent-borne paint systems. As a result, many traditional and highly effective inhibitor systems such as lead compounds, chromates and phosphates, are already prohibited or will shortly be prohibited on the grounds of toxicity and/or environmental effects. Environmental considerations have resulted in increased application of latex (water-borne) paints in place of solvent-borne or “oil-based” paints. Both trends significantly impact upon the formulation of protective paints and the methods of coating application. In brief, the paint industry and industry in general face a growing and urgent need to develop environmentally-acceptable and non-toxic corrosion inhibitors that function effectively in aqueous media.
It is well established that certain substances will reduce and sometimes stop attack by acids on metals, this effect being known as inhibition of corrosion. In fact, numerous compounds can act as inhibitors in a wide variety of media. These compounds fall into two major classes of corrosion inhibitor, Type A and Type B, as shown in FIG. 1 . Type A inhibitors react with the metal, typically by forming an inhibiting layer or film on the surface, while Type B inhibitors act by reducing the aggressiveness of the environment. Only Type IA and IIA inhibitors are relevant to this application of tobacco products.
There is no single mechanism of inhibitor action. However, Type A inhibitors (metal affecters) have been studied most. Types IA and IIA function by reacting with the metal (1) to form a surface film or (2) through selective adsorption onto active anodic (or cathodic) sites on the surface. This adsorption, even in the absence of metal-inhibitor chemical interactions, polarizes the anodic and/or cathodic reaction to provide the corrosion inhibition. Many Type IIA inhibitors incubate corrosion by forming chelate-type reaction products with the metal. In this type reaction, corrosion is inhibited as long as the chelate is present on the surface, with corrosion resuming if the chelate is decomposed or displaced by another surface film.
It is the nature of the chemisorbed layer on the metal formed by Type IA and IIA inhibitors, rather than its thickness per se, that determines inhibitor effectiveness. Non-specific adsorption of ions, or molecules that can form ions, depends upon the surface charge of the metal. At the point of zero charge (ZPC or E q=0 ), adsorption of both ions and molecules can occur. When such adsorption occurs, the ZPC is shifted, in the case of anions, to slightly more negative values. For inhibition by anions, the metal must be held positive to its ZPC, i.e., the metal is positively charged. This generally occurs during corrosion of metals in acid solution. In neutral and basic media, an additional agent such as oxygen is generally required to maintain the metal corrosion potential, E corr , positive to the ZPC, i.e., E corr >E q=0 .
Effective adsorbing inhibitors include aliphatic and aromatic amines, sulphur-compounds such as thiourea and substituted thioureas, carboxylic acids and their salts, aldehydes and ketones, as well as numerous other organic substances. These substances exist either in the charged state, e.g., substituted ammonium cations R 3 NH + in acid solution, or as neutral entities that are readily polarizable such that the active nitrogen atom in N-compounds acquires a net positive charge, and the active sulphur and oxygen atoms in S- and O-compounds acquire a net negative charge as the molecule approaches the metal surface. Thus, in addition to the high surface activity or absorbability of N-, S- and O-compounds due to the polarizability of the active S- and N- atoms in particular, the effect of metal surface charge on adsorption may be predicted. Accordingly, for E>E q=0 , adsorption of S- and O-compounds is favored while N-compound adsorption is preferred when E<E q=0 .
The amounts of any given inhibitor required for effective corrosion control vary with a number of factors, notably solution pH, salinity (chloride content) and temperature. Thus, the action of certain inhibitors can be very pH dependent. E.g., sodium nitrite is relatively ineffective below pH 6 (pH 7.0 being neutrality) and chromates and dichromates are generally effective only at pH values above 7. Likewise, as the salinity of water increases, the amount of inhibitor required also increases. E.g., for sodium nitrite (NaNO 2 ), 50 ppm is required for distilled water in a solution of 500 ppm NaCl; 300 ppm of NaNO 2 is necessary for 50% sea water solution.
Polyphosphates require the presence of divalent cations (e.g., Ca 2+ or Zn 2+ , typically hard waters) to be effective, especially when chloride is present. These inhibitors function best at pH values below 6.0 for ferrous metals but the pH should be raised to 6-7 in mixed metal systems.
Certain inorganic inhibitors will actually accelerate metallic corrosion when present above a certain level (e.g. copper in triethanolamine phosphate).
Amount used
(% w/v)
Compound
[approximate figures]
Cost
Sodium benzoate
1.5-6.0
$12.85/kg
Sodium nitrite
0.3
$15/kg
Sodium benzoate +
1.5 + 0.1
Sodium nitrite
Sodium chromate
0.05-0.1
$81.60/kg
Polyphosphates
50 ppm
$11.90/kg
[Sodium pyrophosphate,
(as P 2 O 5 )
[Sod. pyrophosphate:
Sodium tripolyphosphate,
$40.60/kg]
Sodium hexameta-
phosphate]
Sodium silicate
0.07-0.28
[$15.60/kg
[Sodium metasilicate,
$13/kg]
Sodium orthosilicate]
Triethanolamine
0.14-0.28
$48/kg
phosphate
Synergistic (and antagonistic) effects are often found with mixtures of inhibitors. These effects may be related to the charge in the electrical double layer (edl) present between an electrode (the metal surface) and its environment. The initial stage of adsorption is strongly influenced by the charge in the edl. Prior adsorption of anions, e.g., HS + and Cl − , will lower the potential within the edl and so encourage adsorption of positively charged amines and other N-compounds.
The N- and 0-type compounds are relatively weakly adsorbed and thus tend to be discriminatory in their action, primarily affecting the anodic sites, although effectiveness of inhibition depends upon the molecular size. The primary bonding agent in adsorption is the lone pair of electrons on the O or N atom, although large molecules provide stearic hindrance over both neighboring anodic and cathodic areas so that there is cathodic and anodic inhibition. Aromatic amines and polyamines tend to lie flat on the metal surface. Therefore, their effectiveness of inhibition is a function of the area covered by the molecule, with secondary valence forces holding the molecule to the metal. There have been suggestions that lateral interactions between adjacent adsorbed molecules also increases inhibitive effects.
At least 2549 individual constituents have been identified in tobacco products. However, of this wide variety of constituents, only a limited number are electrochemically active, such activity being dependent upon the presence of the polarizable nitrogen, oxygen and sulphur atoms. Additionally, polynuclear aromatic hydrocarbons might be electrochemically active, due to their fused benzene ring system with its attendant charge dislocation. The average concentrations in dry tobacco leaves of these electrochemically active compounds are summarized in FIG. 2 .
Tobacco products contain high concentration of alkaloids, fatty acids and N-containing compounds, but despite the obvious and wide-spread interest and research into the pharmacological and carcinogenic characteristics of tobacco products, there appears to be no literature on their electrochemical behavior.
EXTRACTION PROCEDURE
Initial aqueous extractions were performed in 1% by weight saline solution at 65° C. (149° F.). These initial extractions and galvanic corrosion studies were performed using a saline solution in order to accelerate the corrosion analyses. In these corrosion studies (i.e., electrochemical tests), an electrical conducting electrolyte medium is necessary to ensure electrical continuity (conductivity) in the circuit (the test medium) to permit accurate electrical measurements to be made. Therefore, by initially using a saline (electrically conductive) solution for the aqueous tobacco constituents extraction, the galvanic corrosion analyses could be run immediately.
Following the initial tobacco constituent extractions in 1% saline aqueous solutions, the inventor performed subsequent tobacco constituent extractions in (1) room temperature (22° C., 72° F.) saline solutions; (2) heated and room temperature water solutions; and (3) heated and room temperature 10% sulfuric acid solutions. In each of these tobacco constituent extractions, the mechanical procedure was the same. The tobacco product was stirred into the extraction medium, namely water, saline or acid solution in a large beaker, and was agitated by a magnetic stirrer over a period of 4 hours. The mix was filtered through a standard laboratory filter paper in a conical funnel, and the various metallic surfaces were immersed in individual containers of the filtrate solution for the specified times.
GALVANIC CORROSION STUDIES
The prepared tobacco extract solution was used for specific galvanic corrosion cell zero resistance ammetry analyses of the current density/time relationships of galvanic couples of various metal combinations, and compared to analyses of current density/time relationships of these same galvanic couples in 1% saline solution with and without the addition of 1% potassium chromate. Results of these analyses indicate that extracts leached from these various types of tobacco inhibited corrosion within these galvanic couple corrosion cells in 1% saline solution considerably better than additions of 1% potassium chromate, commonly used as a corrosion inhibitor.
Three series of these electrochemical corrosion tests were performed to evaluate the electrochemical behavior and the corrosion inhibition potential of tobacco constituents and to compare their efficacy with that of aqueous extracts from smokeless tobacco.
Galvanic corrosion cells are established wherever metals of different electrochemical potential are coupled together or where there are differences in electrochemical activity arising from variations in such factors as pH and aeration. Galvanic corrosion currents may be accurately studied by means of zero resistance ammetry, ZRA. In ZRA, the feedback current of the operational amplifier of a potentiostat is used to maintain a zero potential difference between the two metals of the galvanic couple. The magnitude of the feedback current is identical to that flowing in the galvanic cell. This technique was used to obtain the following data:
a. the magnitude of the corrosion currents flowing in cells formed by combinations of dissimilar metals;
b. the effect of tobacco constituents on the galvanic corrosion currents;
c. changes in the effect of tobacco constituents on galvanic corrosion currents as a function of electrolyte pH; and
d. the effect of elevated temperature on inhibition of galvanic corrosion by tobacco constituents.
The data obtained indicate the protective efficacy of constituents from different tobaccos on corrosion in galvanic cells, and indicate the effect of solution pH and solution temperature on the inhibitive effects.
Accordingly, studies were performed using the rapid and convenient zero resistance ammetry (ZRA) technique.
EXAMPLE 1
A tobacco extract test medium was prepared by digesting 5 g of commercial chewing tobacco (Red Man chewing tobacco, Pinkerton Tobacco Co, Owensboro, Ky.) in 500 ml of 1% saline for a period of 4 hours. A study compared the effects of 1% NaCl solution, 1% saline containing the tobacco extract and 1% saline containing 1% of the known inhibitor, potassium chromate, on the industrially important copper-steel galvanic couple. The current density/time relationships of the galvanic couple in these solutions are shown in FIG. 3 . Increased corrosion inhibition is denoted by a lower current density.
This study on the copper-steel galvanic couple clearly shows that a simple aqueous extract of smokeless tobacco leached out a powerful corrosion inhibitor, one that is more effective and more rapid in its action than the well-established anodic passivating inhibitor, potassium chromate.
EXAMPLE 2
ZRA studies of mild steel coupled to platinum, a very active cathode, in 1% saline solution, with and without potassium chromate, smokeless tobacco extract and Cavendish smoking tobacco extract are shown in FIG. 4 . Again, a lower current density denotes a greater degree of corrosion inhibition. Note that both tobacco extracts are more effective corrosion inhibitors, i.e., produce a lower current density, than the standard corrosion inhibitor, potassium chromate.
EXAMPLE 3
ZRA studies of brass coupled to platinum in 1% saline solution, with and without potassium chromate, smokeless tobacco extract and Cavendish smoking tobacco extract are shown in FIG. 5 . Again, a lower current density denotes a greater degree of corrosion inhibition. Both tobacco extracts are considerably more effective corrosion inhibitors, i.e., produce a lower current density, than potassium chromate.
EXAMPLE 4
ZRA studies of aluminum coupled to platinum in 1% saline solution, with and without potassium chromate, smokeless tobacco extract and Cavendish smoking tobacco extract are shown in FIG. 6. A lower current density denotes a greater degree of corrosion inhibition. Both tobacco extracts are more effective corrosion inhibitors, i.e., produce a lower current density, than potassium chromate.
EXAMPLE 5
ZRA studies of mild steel coupled to brass in 1% saline solution, with and without potassium chromate, smokeless tobacco extract and Cavendish smoking tobacco extract are shown in FIG. 7. A lower current density denotes a greater degree of corrosion inhibition. Both tobacco extracts are more effective corrosion inhibitors, i.e., produce a lower current density, than potassium chromate.
EXAMPLE 6
ZRA studies of mild steel coupled to aluminum in 1% saline solution, with and without potassium chromate, smokeless tobacco extract and Cavendish smoking tobacco extract are shown in FIG. 8. A lower current density denotes a greater degree of corrosion inhibition. Both tobacco extracts are more effective corrosion inhibitors, i.e., produce a lower current density, than potassium chromate.
EXAMPLE 7
ZRA studies of aluminum coupled to brass in 1% saline solution, with and without potassium chromate, smokeless tobacco extract and Cavendish smoking tobacco extract are shown in FIG. 9. A lower current density denotes a greater degree of corrosion inhibition. Both tobacco extracts are more effective corrosion inhibitors, i.e., produce a lower current density, than potassium chromate.
These data clearly demonstrate the effectiveness of aqueous tobacco extracts in corrosion inhibition.
EXAMPLE 8
Additional work has been performed on corrosion inhibition of 10% sulfuric acid, a medium commonly used in the metal finishing and metal processing industries for descaling steel prior to electroplating, painting, and other surface coating procedures, as well as prior to most metal working operations. Scrap burley twigs and stems, after stripping of leaves and shoots for processing into tobacco products, were digested in 10% H 2 SO 4 solution to provide a concentration of 5% extract in the acid. Mild steel was then immersed in plain acid and the acid-burley extract for 5 minute intervals up to a total of 20 minutes, weight changes being recorded after each 5 minute period. The weight loss data are shown in FIG. 10 . As indicated, the 10% acid solution etched away surface metal in an essentially linear time relationship following an initial period of accelerated metal loss during the first five minute interval, whereas, the acid-barley extract maintained the metal loss at a near-zero level for at least 15 minutes before permitting the rate of metal loss to increase slightly some time during the fourth five minute period.
This work clearly demonstrates the inhibitive effect of burley twigs and stems, materials that are discarded during tobacco processing.
The extracted corrosion inhibitors may be used to treat metallic surfaces in any number of conventional methods, such as dip- or spray-coating, electrostatic coating, etc. In addition, the extracted corrosion inhibitors may be combined with, or otherwise formulated with, paint or other surface coating material, to effect the corrosion inhibition of such painted or coated metallic surface.
ALTERNATIVE EXTRACTION PROCEDURES
There exist numerous alternative extraction procedures involving different extraction media for extracting the metallic corrosion inhibiting components from tobacco. One of these procedures is supercritical fluid extraction (SFE). There are three different modes of extraction procedure using SFE technology: (1) static extraction; (2) dynamic extraction; and (3) a combination static/dynamic extraction.
In the static mode SFE procedure, tobacco is introduced into a specified amount of supercritical fluid at a specified temperature. Frequently, the extraction vessel is pressurized to enhance the interaction between the metallic corrosion inhibitors in the tobacco and the supercritical fluid. In addition, the specified amount of supercritical fluid solution may be recirculated within the extraction vessel to enhance the extraction process. In addition, frequently the static extraction process is followed by a specified period of time of dynamic extraction in order to maximize the extraction process.
When the extraction is complete, the solid tobacco residue is removed from the supercritical fluid solution, commonly by mechanical filtering, and the resulting supercritical fluid solution containing the metallic corrosion inhibitors extracted from the tobacco can be used in a number of applications to treat specific metallic surfaces for corrosion inhibition.
In a dynamic extraction process, fresh supercritical fluid is continually passed through the tobacco product, similar to the way a coffee maker percolates fresh water through ground coffee beans. This process, obviously, utilizes much more of the supercritical fluid than the static SFE process. In addition, there is a greater opportunity for impurities in the supercritical fluid to contaminate, or otherwise affect the efficiency of, the extraction process and/or the resulting extracted metallic corrosion inhibitors.
A combination initial static extraction followed by a secondary dynamic extraction, as mentioned above, appears to be the preferred mode for the extraction of metallic corrosion inhibiting components from tobacco. In this process, the static extraction is carried out as above-described for a predetermined period of time. Following the static extraction, the supercritical fluid/metallic corrosion inhibitor component solution is transferred, generally in a closed system, into an apparatus for dynamic extraction. In the transferring, the supercritical fluid/metallic corrosion inhibiting component solution is removed, and replaced with fresh supercritical fluid, which is then passed through the tobacco in the dynamic extraction process. The metallic corrosion inhibitors in solution are then utilized to treat metallic surfaces for corrosion inhibition. It has also been found that a number of static/dynamic extraction cycles may be used to maximize the efficiency with which the metallic corrosion inhibitors may be extracted from the tobacco product.
The inventor has also determined that metallic corrosion inhibitors may be extracted from tobacco by the use of media other than water, saline aqueous solutions, and supercritical fluids. In one of these alternative methods, metallic corrosion inhibitors may be extracted from tobacco in an oil medium solution, following a procedure similar to that utilized in the previously described water and 1% saline solutions. Variations of the oil medium solution extraction method would include performing the extraction step at specified ranges of temperatures and pressures, agitating the tobacco in the oil medium solution, and recirculating the oil medium solution for improved extraction efficiency. Other embodiments of metallic corrosion inhibitor extraction from tobacco comprise extraction in various emulsion media and various alkaline and salt (basic) solution media. Again, the procedure to be followed would be essentially identical to that described above with relation to the water, 1% saline, and oil medium extraction procedures.
Lastly, metallic corrosion inhibitors may be extracted from tobacco in a steam medium at specified temperatures and pressures, followed by condensing the steam, including the extracted corrosion inhibitors, into solution for treating metallic surfaces with the inhibitors.
Cementitious compounds, typically Portland cement, plaster and concrete, are mixed with water to produce a plastic mass that sets to a solid mass. When dry, these materials exhibit high compressive strength and good durability. However, when wet, they tend to be unstable with a high pH so that they are subject to degradation by low pH media, typically acid rain. Further, because they lack tensile strength, cementitious substances, such as concrete used for construction purposes, are often reinforced with steel rods to increase their resistance to tensile and flexural loads. The high pH of the cementitious mass has a deleterious effect on many metals. Iron and steel, for example, will corrode when imbedded in cement or concrete that has imbibed water, thereby releasing the basic substances that raise the pH at the metal surface. The incorporation of tobacco extracts in the mixing water for the cement, cement-render, plaster or concrete will have no adverse effects on the mechanical or physical properties of the set mass but will function as a corrosion inhibitor for the metal surface. The mechanism for this action is that when rain water, for example, enters the set mass, it will release the tobacco extract which will migrate with the inward diffusing water to the metal surface and inhibit the corrosion that otherwise would occur at the metal surface.
Sodium chloride, salt, and similar chemicals are used as de-icing agents on ice- and snow-covered roadways etc. to melt the ice layer and reduce the risk of slippage and loss of traction by motor vehicles, pedestrians etc. Although these de-icing salts are effective in melting ice by lowering the freezing point of the salt water mix that forms when salt is spread over ice, the resultant brine solution is a highly aggressive electrolyte that will corrode many metals, notably iron and steel. Incorporating the corrosion-inhibitive tobacco extract in the de-icing medium, probably as a dry powder that will be activated when the “salt” becomes wetted on application to snow and ice, will provide an effective means of reducing the corrosive attack on motor vehicles and other metallic structures that are exposed to the brine solution formed during de-icing operations.
A variety of media are used during such metal-working operations as drilling, milling, cutting, grinding, polishing and so forth to aid the cutting action of the abrasive medium or cutting tool through a lubricating action as well as provide cooling during the metal removal process. Such media often are water-based, e.g. emulsion cutting fluids, or contain varying amounts of water. If these media are left on the metal surface after the operations are finished, corrosion of the metal surface may occur. Further, during the metal-working operations, metallic particles and other matter are introduced from the metal workpiece surface as well as from the cutting or metal working tool. Because these substances accumulate within the cutting fluid, they may deposit out on other pieces of metal during subsequent metal-working operations. Such deposits may establish galvanic corrosion cells if their depositions result in local or general differences in chemical composition, metallurgical structure, pH, or aeration on the metal workpiece surface. The presence of tobacco extract with its known anti-corrosive (corrosion inhibitive) properties would reduce the risk of metal damage due to corrosion caused by the residual cutting fluid on the metal surface or extraneous matter deposited during such metal working operations.
From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objectives herein set forth, together with other advantages which are obvious and which are inherent to the composition and method. It will be understood that certain features and subcombinations are of utility and may be employed with reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. As many possible embodiments may be made of the invention without departing from the scope of the claims. It is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense. | A method of extracting corrosion inhibiting constituents from tobacco comprises the steps of soaking tobacco in an extraction solution under certain extraction conditions, followed by filtration to remove tobacco residue from the resultant aqueous tobacco solution. This tobacco solution is used as a corrosion inhibitor to minimize the amount of corrosion occurring at galvanic corrosion cells that are established at areas of union of metals having different electrochemical potentials. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a process for manufacturing a cheese product. The cheese product is typically elongated in form, featuring a longitudinal fibrous texture which permits the product to be eaten by pulling off strips. While a variety of cheeses may be used, Italian type cheeses have been found useful in making the product because of their naturally stringy properties.
In the past, the manufacture of this type of product has generally been attempted by hand. A loaf of cheese was kneaded into a ribbon. Short lengths of the cheese were then pulled by hand or placed on a taffy puller. While this did provide such a product, these processes were not feasible from a commercial standpoint because of slowness, breakage of the cheese on the taffy puller, and for other reasons.
SUMMARY OF THE PRESENT INVENTION
It is, therefore, the object of the present invention to provide a highly efficient and effective process for producing a fibrous texture cheese product of uniform and highly satisfactory quality.
In the process of the present invention, a heated mass of cheese is extruded on a continuous basis. This is followed by a subsequent pulling or tensing of the extruded strand which is also carried out on a continuous basis. The cheese is cooled while it remains under tension, thereby to retain the fibrous properties and sizing produced by pulling the cheese strand.
To this end, a strand of cheese is extruded by an extruder. The continuously extruded strand is thereafter subjected to longitudinal tension, as by wrapping the strand around a pair of rotating drums. The pulling produced by the drums induces the fibrous texture in the strand and reduces its size by elongation. The cheese is cooled in conjunction with or after the elongation as by passing it down a water filled pipe.
The tension applied to the strand is maintained, while the cheese is further cooled in a vat by additional tension applying means which may comprise a plurality of driven rollers which grip the cheese strand between them. The strand of cheese so pulled and cooled is severed into consumer portions and packaged.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a cheese product manufactured by the process of the present invention.
FIG. 2 is an elevational view of an apparatus for carrying out the process of the present invention. For clarity, the Figure is somewhat schematic in form.
FIG. 3 is a plan view of the extruder incorporated in the apparatus showing additional details thereof.
FIG. 4 is a perspective view of a tension applying means forming part of the apparatus.
FIG. 5 is a perspective view of a tension maintaining means forming part of the apparatus.
FIG. 6 is a fragmentary perspective view of a cooling water vat used in the apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a cheese product 2 manufactured by the process of the present invention. Cheese product 2 is typically elongated in form having a diameter of approximately 5/8 to 7/8 inches. The product is characterized by a longitudinal fibrous texture property that permits portions 4 along the edge to be peeled off the central portion, as shown in FIG. 1. The stripping of portion 4 reveals the cheese fibers 6.
FIG. 2 shows apparatus 10 for making cheese product 2. Apparatus 10 includes extruder 12. Extruder 12 has bin 14 for receiving cheese as shown in FIG. 3. Typically, the manufacturing of the cheese to be processed by apparatus 10 will have proceeded to a point short of that at which it would otherwise be packaged. For example, in the case of Italian type cheeses, the cooking of the cheese, which converts the curds to a homogeneous plastic mass will be complete. The cheese placed in bin 14 is thus a viscous mass having a temperature of approximately 150° F.
Bin 14 contains auger 16 or other means for feeding the cheese into extrusion head 18 so that it may be extruded from nozzle 20. Extruder head 18 preferably includes hot water jacket 22 for maintaining the temperature of the cheese so that the cheese emerges from extrusion nozzle 20 at a temperature slightly lower than 150° F., for example about 145° F. As will be noted in FIG. 2, extruder 14 is typically elevated with respect to the other portions of apparatus 10 on stand 23.
The strand of cheese 24 emerging from extrusion nozzle 20 passes onto a series of rollers, 26a, 26b, and 26c for conveying the cheese strand to other portions of apparatus 10. To maintain the desired consistency and other properties of the cheese strand 24, a steam hood 28 is mounted over the rollers to play steam vapor or hot water supplied by conduits 30 and 32, onto the extruded strand as it passes over the rollers.
Strand 24 then passes into pipe 34. Pipe 34 contains a coolant supplied by conduits 36 and 38. The coolant is preferably a brine solution which both cools and commences the brining of the cheese necessary to obtain the desired flavor. The brine absorption is higher in the hot cheese emerging from extruder 12 and hood 28 than in the cheese after it has further cooled. The coolant also facilitates passage of strand 24 through the pipe. Additional cooling of strand 24 occurs in vat 40 containing brine 42.
Apparatus 10 includes means 44 for applying tension to extruded cheese strand 24. Tension applying means 44 includes a pair of drums 46 and 48 positioned in tandem, or one behind the other, in the path of extruded cheese strand 24. See FIGS. 2 and 4. Drums 46 and 48 contain one or more trough-like guides 50 on the periphery for receiving cheese strand 24. With the drums oriented as shown in FIG. 2, drum 46, or the rearward drum in the direction of extrusion, is rotated in a clockwise direction and forward drum 48 is rotated counterclockwise. For this purpose, drum 46 is mounted on shaft 52 and drum 48 is mounted on shaft 54. Shafts 52 and 54 may be journalled in bearings 56 on vat 40.
The drive 48 for drums 46 and 58 is shown in greater detail in FIG. 4. While a variety of variable speed drives may be used, drive 58 is shown as utilizing a d.c. motor 60. The output shaft of d.c. motor 60 is connected to pulley 62, which in turn is connected to pulley 64 on shaft 52 to drive drum 46 through belt 66. Pulley 68 is mounted on shafts 52 with pulley 64 and is connected through crossed belt 70 to pulley 72 mounted on shaft 54 of drum 48. Motor 60 may be energized by adjustable power supply 74 to control the speed of drums 46 and 48.
As shown most clearly in FIG. 2, cheese strand 24, as it emerges from pipe 34, is received in guide 50 at the top of drum 46. It proceeds around drum 46 in the direction of its rotation, emerging from the other side of drum 46 and is received in guide 50 of drum 48. From there it proceeds around drum 48 in the direction of its rotation and is discharged off the bottom of drum 48 to proceed along vat 40. As shown in FIGS. 2 and 4, brine 42 in vat 40 is preferably established at a level such that the lower portion of drums 46 and 48 are immersed in the water. A spring-loaded idler roll 76, shown in FIG. 4 is provided near the point at which cheese strand 24 is discharged from drum 48 to direct the cheese strand down vat 40.
With the strand 24 of cheese wrapped around drums 46 and 48, power supply 74 is adjusted so that the peripheral speed of drum 46 and 48 is greater than the speed of cheese strand 24 from extrusion nozzle 20. This exerts a tensile or pulling force on strand 24 which both induces the fibrous texture properties in the strand and reduces its size by elongation. Because the cheese is hot, most fiber production and elongation occurs in the region of steam hood 28 and coolant pipe 34, for example as strand 24 exits the steam hood and before it is significantly cooled in pipe 34. Some additional elongation may occur before and intermediate the drums.
As cheese is a natural product, the amount of tensile force required to produce the desired texture and size properties will vary with differences in the chemical composition of the milk used to make the cheese, the cheese manufacturing process and the temperature of the cheese. The degree of fibrous texture which can be produced is determined by the cheese itself. Enough tension is thus applied to maximize fibrous texture production in the particular cheese forming strand 24. If this tension is not sufficient to reduce the size of strand 24 to that necessary for consumer packaging, additional tension is applied for size reduction purposes. Thus, in actual production, tension is often established responsive to an inspection of the resulting product. The tension applied to cheese strand 24 will typically range between 20 and 40 pounds. Tension of the appropriate magnitude may reduce the diameter of an extruded cheese strand of 11/2-2 inches down to about 5/8 to 7/8 as it is discharged from drum 48. If desired, the size of the cheese strand 24 discharged from drum 48 may be measured, as by sensor 77 and used to control the tension applied by drums 46 and 48. The cooling provided by the brine in pipe 34 and vat 40, as well as exposure to the air, reduces the temperature of cheese strand 24 to about 95° F. at discharge from the drums.
Apparatus 10 includes a second means 80 for maintaining the tension on cheese strand 24 downstream of drums 46 and 48. Tension applying means 80 may also be mounted on vat 40. As shown most clearly in FIG. 5, means 80 includes a frame 82 on which are mounted a plurality of pairs of opposing rollers 84a and 84b, 86a and 86b, and 88a and 88b. Rollers 84b, 86b, and 88b are driven by an adjustable drive means 90 which may be similar to drive 74. Opposing rollers 84a, 86a, and 88a are spring-loaded and bear on rollers 84b, 86b and 88c. The rollers grip cheese strand 24 passing through the rollers and may be roughened for this purpose. The speed of drive 90 and rollers 84, 86 and 88 is adjusted so that the tension on cheese strand is continued after it leaves drum 48. It will be appreciated that other means, such as opposed moving belts may be used instead of rollers.
The tension applied to the strand by means 80 may be the same as that applied by means 44 but is usually less. Its purpose is to maintain the texture and size properties of strand 24 until it has cooled to the point where these properties become locked in. Because partially cooled cheese is elastic, strand 24 might resile from its stretched condition if the tension was not maintained, resulting in loss of desired texture and size properties. The additional tension also contributes to finer fiber development in strand 24.
The spacing of tension applying means 44 from extruder 12 and from tension applying means 80 is established in accordance with the properties and temperature of the cheese, the desired size of the cheese product 2, and other factors.
Means 80 may also include a device for cutting strand 24 into lengths suitable for packaging. For this purpose limit switch 92 is mounted so as to be struck by the strand 24 of cheese after it passes through rollers 88a and 88b. Limit switch 92 is connected to a solenoid 94 which operates cut-off knife 96 and to solenoid 98 which rocks tray 100 between a first position in which holder 102 receives the strand of cheese before and during cutting and a second position in which holder 104 receives cheese and holder 102 tips the previously cut cheese into vat 40. In the next cycle, holder 100 is rocked back in the other direction.
Brine 42 circulating in vat 40 cools strand 24 and the pieces 106 cut therefrom and continues the brining of the cheese. Brine 42 carries pieces 106 in the serpentine path shown in FIG. 6 to a packaging apparatus, not shown, which packages the pieces for commercial distribution. Injector 108 in extruder 12 may be used to inject a brine solution in the cheese as it is extruded to reduce brining times in vat 40.
Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention. | In a process and apparatus for manufacturing an elongated cheese product, the extrusion of a heated mass of cheese is followed by a subsequent pulling or tensing of the extruded strand which develops a fibrous texture in the product and reduces the size of the strand. The pulling is carried out on a continuous basis by a tension applying device, downstream of the extruder, which may comprise a pair of drums around which the cheese strand is wrapped. The strand then passes down a cooling vat under tension from a second tension applying device which retains the properties of the strand as it cools. The second tension applying means may include pairs of driven rollers through which the cheese strand passes. After the pulling and cooling, the strand is cut in lengths suitable for packaging. | 0 |
BACKGROUND OF THE INVENTION
The invention relates generally to flow sensors, and more particularly, to variable orifice fluid flow sensors.
Orifice flow sensors are used to measure the flow rates of fluids, which include liquids and gases. A typical orifice flow sensor comprises a fixed orifice through which a fluid is made to flow. A pressure difference is established between the fluid that is present upstream from the orifice and the fluid that is flowing through the orifice. This pressure difference can be used to measure the flow rate of the fluid. For this purpose, a pressure transducer measures the pressure difference that is established across the orifice, and is calibrated such that the flow rate of the fluid is calculated from this pressure difference.
Variable orifice flow sensors provide sufficient pressure difference for measurement purposes across a broad range of flow rates. This is achieved by introducing a bending member into the fluid flow passage. The bending member is mounted to the housing for the fluid flow passage and includes a flapper that is positioned across the fluid flow passage and bends or flexes in the direction of the fluid flow as a result of contact with the fluid flow, and hence creates a variable orifice within the fluid flow passage. The measurement of flow rates in a variable orifice flow sensor is similar to the measurement of flow rates in fixed orifice flow sensors. That is, a pressure transducer measures the pressure difference across the variable orifice and calculates the flow rate of the fluid from the pressure difference.
U.S. Pat. Nos. 4,989,456; 5,033,312; 5,038,621; 6,722,211 and 7,270,143 show variable orifice flow sensors.
The performance of the sensor can be directly influenced by the connection of the bending member including the flapper to the housing that defines the fluid flow passage. In situations where the bending member is rigidly secured to the housing, this tight engagement with the housing can distort the movement of the flapper to negatively affect its operation. Further, in situations where the bending member is too loosely secured to the housing, it is possible for fluid to flow around the bending member through leaks located between the housing and the bending member.
In either situation, the movement and operation of the flapper is affected by the connection of the bending member to the housing, and hence the measured pressure difference across the variable orifice defined by the flapper becomes altered, such as by poor low flow resolution and non-linear movement of the flapper. This, in turn, leads to inaccurate measurements of the flow rate of the fluid.
BRIEF DESCRIPTION OF THE INVENTION
In the present invention a variable orifice fluid flow sensor is provided having two port portions engaged with one another that form a fluid flow passage through the sensor. A variable orifice device with a bending member including a fluid flow limiting flapper is provided between the two port portions. The variable orifice device also includes a biasing member that is disposed between the two port portions and that engages the bending member around the gas flow passage. The biasing member includes a number of biasing elements that extend outwardly from the biasing member into contact with the bending member. The engagement of the biasing elements with the bending member provides a constant contact and/or biasing force against the bending member to hold the bending member relative to the two port portions in a manner that does not negatively affect the operation of the flapper in determining a fluid flow pressure differential and measuring the corresponding fluid flow rate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a variable orifice fluid flow sensor in accordance with an exemplary embodiment of the invention.
FIG. 2 is an exploded isometric view of a variable orifice fluid flow sensor in accordance with another exemplary embodiment of the invention.
FIG. 3 is an isometric view of a biasing member and a bending member of a variable orifice fluid flow sensor in accordance with an exemplary embodiment of the invention.
FIG. 4 is a cross sectional view of a variable orifice fluid flow sensor in accordance with yet another exemplary embodiment of the invention.
FIG. 5 is a partially broken away cross sectional view of a variable orifice fluid flow sensor in accordance with yet another exemplary embodiment of the invention.
FIG. 6 is a partially broken away cross sectional view of a variable orifice fluid flow sensor in accordance with yet another exemplary embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates an isometric view of a variable orifice fluid flow sensor 100 in accordance with one embodiment of the present invention. Variable orifice fluid flow sensor 100 develops pressure differences that are used to measure flow rates of fluids, such as gases, flowing through the flow sensor 100 . Therefore, variable orifice fluid flow sensor 100 can also be referred to as a differential pressure variable orifice gas flow sensor. Variable orifice gas flow sensor 100 has a generally cylindrical configuration. However, variable orifice gas flow sensor 100 may be formed in a variety of shapes and sizes and still lie within the scope of this invention.
FIGS. 2-4 illustrate variable orifice gas flow sensor 100 comprising a housing 102 that includes a first port portion 104 and a second port portion 106 that are connected to one another to define a gas flow passage 108 therein through which a gas flows. A sealing member 110 is disposed and engaged between the first port portion 104 and the second port portion 106 to prevent gas flowing through the gas flow passage 108 from exiting the passage 108 between the first port portion 104 and second port portion 106 . When variable orifice gas flow sensor 100 is used for measuring gas flow rates in a breathing apparatus, a flow sensor 100 is inserted at one or more desired locations in a breathing circuit.
Variable orifice gas flow sensor 100 includes a bending member 112 intermediate to first port portion 104 and second port portion 106 . Bending member 112 is generally complementary in shape to the shape of the gas flow passage 108 , and includes an outer peripheral member 114 that a diameter larger than the diameter of the gas flow passage 108 , such that a portion of the outer peripheral member 114 is disposed within a gap 116 defined between first port portion 104 and second port portion 106 when engaged with one another. The gap 116 can be formed to have the desired with, but hi an exemplary embodiment is formed to be approximately 0.005 inches in width.
To maintain the position of the outer peripheral member 114 and bending member 112 relative to the first port portion 104 and second port portion 106 , outer peripheral member 114 includes a number of apertures 118 formed therein that are alignable and positionable on mounting projections 120 formed on first port portion 104 and/or second port portion 106 . The mounting projections 120 operate to properly locate the bending member 112 with respect to the first port portion 104 and second port portion 106 an to prevent rotation of the bending member 112 with respect to the first port portion 104 and second port portion 106 . Alternatively, in another exemplary embodiment, the apertures 118 and the projections 120 can be omitted entirely or substituted therefor by another suitable structure.
The bending member 112 also includes a fluid or gas flow limiting flapper 122 that is connected at one end to the outer peripheral member 114 and extends inwardly into and across the gas flow passage 108 to separates first port portion 104 and second port portion 106 . Because gas flow limiting flapper 122 is attached at one end to the outer peripheral member 114 , as gas flows along the gas flow passage 108 through variable orifice gas flow sensor 100 , gas flow limiting flapper 122 bends or flexes in the direction of the flow of the gas. For this purpose, gas flow limiting flapper 122 , and outer peripheral member 114 when formed integrally with flapper 122 , is made from a resilient material. For example, gas flow limiting flapper 122 can be made from resilient plastic or a metal. The bending of gas flow limiting flapper 122 leads to the formation of an increased fluid or gas flow opening 123 in the gas flow passage 108 . This gas flow opening 123 defined between the outer peripheral member 114 and the flapper 122 varies with the bending of gas flow limiting flapper 122 due to the flow rate of the gas within the passage 108 . A pressure difference is established across gas flow limiting flapper 122 . This pressure difference is measured by means of a conventional pressure transducer (not shown in FIGS. 2-4 ). Gas pressures are provided to the pressure transducer through pressure measurement ports 124 and 126 , which open into the gas flow passage upstream and downstream of flapper 122 on first port portion 104 and second port portion 106 , respectively. The pressure transducer is calibrated such that the flow rate of the gas through variable orifice gas flow sensor 100 is obtained from the pressure difference across gas flow limiting flapper 122 .
FIGS. 2-5 illustrate a biasing member 128 that is positioned between first port portion 104 and second port portion 106 within the gap 116 . The biasing member 128 is formed with any suitable shape and of any suitable resilient material, such as a resilient plastic or a metal. In the illustrated exemplary embodiment, the biasing member 128 is formed as ring 130 that defines a central opening 132 therein. The ring 130 is positioned within the gap 116 with the central opening 132 disposed around gas flow passage 108 so as not to obstruct gas flow through the passage 108 or the movement of the flapper 122 . The ring 130 also includes a pair of apertures 134 that are formed similarly to apertures 118 in outer peripheral member 114 of bending member 112 , though any number of apertures 134 can be utilized, or the apertures 134 can be omitted entirely. The apertures 134 are positioned over the mounting projections 120 to locate the ring 130 properly with respect to the bending member 112 as well as first port portion 104 and second port portion 106 , and to prevent rotation of ring 130 .
Biasing member 128 also comprises a number of biasing elements 136 disposed on the ring 130 that extend inwardly from the ring 130 into the central opening 132 . The biasing elements 136 can extend from the inner edge of the ring 130 , or can be separated from the ring 130 by slots 138 disposed on each side of the biasing element 136 that extend into the ring 130 . The biasing elements 136 contact the outer peripheral member 114 of the bending member 112 to act on the bending member 112 in a manner that holds the bending member 112 in position between first port portion 104 and second port portion 106 with the desired amount of force to enable proper operation of the flapper 122 on the bending member 112 . In the exemplary embodiment in the drawing figures, the biasing elements 136 take the form of tabs 140 that are at least partially bent at an angle with respect to the plane of the ring 130 , forming biasing member 128 as a spring washer. The tabs 140 provide localized points of force on the bending member 112 , thereby providing a constant biasing force on the outer peripheral member 114 to hold the bending member 112 in the desired position. The size, number and angle of the tabs 140 can be varied from the configuration shown in the exemplary embodiment of the invention showing equidistant tabs 140 , along with the material from which the biasing member 128 is formed, to provide the desired amount of force from the tabs 140 on the bending member 112 and enable the flapper 122 to operate correctly, but without distorting the flapper 122 or allowing leaks to form around the bending member 112 in the gas flow passage 108 . Further, the use of the biasing member 128 secures the bending member 112 within the gas flow passage 108 with looser assembly tolerances between first port portion 104 and second port portion 106 and without the need for any direct securing of the bending member 112 and/or biasing member 128 to the housing 102 , including any additional securing means or members, such as adhesives, fasteners or threaded components on first port portion 104 and second port portion 106 . It is also contemplated that the only structure holding the bending member 112 in position in the sensor 100 is the biasing member 128 , such that the bending member 112 may float within the gap formed between the first port portion 104 and second port portion 106 under the bias of the biasing member 128 .
FIG. 6 illustrates another exemplary embodiment of the invention in which the biasing elements 136 contact the outer peripheral member 114 of the bending member 112 within holes 142 formed in the outer peripheral member 112 . In this configuration, the tabs 140 apply a force at an angle to the axis of the bending member 112 when the tabs 140 engage an edge or surface 144 of the hole 142 in the bending member 112 . This further assists in holding the bending member 112 in position between first port portion 104 and second port portion 106 with the desired amount of force to enable proper operation of the flapper 122 on the bending member 112 .
Variable orifice gas flow sensor 100 may be of the single use, disposable type or of the multiple use, reusable type. The former will typically be manufactured from inexpensive plastic material. The latter will usually be manufactured from autoclavable materials, such as metal or high temperature resistant plastic(s).
Variable orifice gas flow sensor 100 may also optionally include one or more fixed orifices (not shown) and a flow-limiting member (not shown). The fixed orifice ensures that gas flows having a velocity that is insufficient to cause bending of gas flow limiting flapper 122 can pass through variable orifice gas flow sensor 100 . This can be achieved by shaping gas flow limiting flapper 122 such that there is space for the gas flow to pass through. A flow limiting member restricts the bending of gas flow limiting flapper 122 to provide an appropriate pressure difference across the flapper for high flow rates.
The various embodiments of the invention provide a variable orifice gas flow sensor 100 that is capable of reproducibly measure a broad range of flow rates by attaching the bending member 112 to the housing 102 for the variable orifice fluid flow sensor 100 in a manner that minimizes the effect of the attachment on the operation of the bending member 112 .
The written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. | A variable orifice fluid flow sensor is provided that includes a fluid flow passage therethrough formed with a first port portion adjacent to one end of said passage and a second port portion adjacent to the other end of said passage. A bending member is mounted in the fluid flow passage between the first and second port portions and having a fluid flow limiting flapper extending across the fluid flow passage for creating a fluid flow opening in the passage, the size of the opening being variable responsive to fluid flow in said fluid flow passage. A biasing member is also mounted between the first and second port portions and includes at least one biasing element extending away from the biasing member into contact with the bending member to exert a contact force on the bending member. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method and an apparatus for rounding off edges.
2. Description of the Prior Art
In many component parts that are under heavy loads mechanically, thermally or in other ways, all kinds of peak stresses occur that entail the risk of failure of the component. It has long been known to at least partly abate these peak stresses by making undercuts and/or radii and thus to shift the load limit of the component upward. In many components, proceeding in this way has its limits, since the requisite cutting tools, such as lathe chisels, radius milling cutters, grinding bodies or the like require a certain amount of space, and this need cannot always be met. In fuel injection systems, for instance, various heavily loaded components are present that are inaccessible, or accessible only at major effort, to the above tools.
In other components, such as injection nozzles, the presence of edges that are rounded off in a defined way is important, in order to keep the flow resistance of the component within a narrow tolerance range. For this group of components as well, there has until now been no method or apparatus for rounding off the edges that are definitive for the flow resistance with high replicability and at little cost.
From U.S. Pat. No. 5,807,163, a method for rounding off the edges of the tiniest drilled bores, such as injection ports of injection nozzles, and for calibrating the tiniest bores is known. So-called flow grinding with a polymeric plastic composition is also known. Both methods are unsuited to removing the macroscopic burrs, created in the production of common rails for fuel injection systems, economically and rounding off the edges that are present.
It is the object of the invention to furnish a method with the aid of which edges can be rounded off even at inaccessible places, with high replicability and a high rate of removal of material and at favorable cost.
According to the invention, this object is attained by a method for rounding off edges in which the edge to be rounded off is bathed by an erosive fluid; between the pressures of the erosive fluid before and after the bathing of the edge to be rounded off, there is a pressure difference of from 50 bar to 140 bar.
SUMMARY OF THE INVENTION
The method of this invention has the advantage that edges that may be present at virtually arbitrary places in components, even if the edges are of complicated geometry, can be rounded off. The expense for equipment is tolerable, the machining time is short, and the rounding-off quality is high. Furthermore, only slight costs are entailed. By continuously measuring the quantity of the erosive fluid, high process reliability is gained. The removal of material is the greatest at edges, because of what as a rule is an elevated flow speed, so that at the other places subjected to the erosive fluid, no removal of material or only slight removal of material occurs. The flow behavior of the erosive fluid, in components experiencing a flow through them, such as high-pressure fuel reservoirs of fuel injection systems, is equivalent to that of the fuel in operation, so that the rounding off according to the invention at the same time brings about a desired artificial aging of the component.
In a variant of the method of the invention, the flow speed of the fluid in the region of the edge to be rounded off is elevated compared to the average flow speed of the fluid, so that an especially large amount of removal of material is attained in the region of the edge to be rounded off.
In a further feature of the method, a body is introduced into the fluid, the surface of which body forms a gap with the edge to be rounded off, so that the flow speed of the fluid in the region of the edge to be rounded off is increased still further compared to the average flow speed of the fluid, and thus the removal of material is increased further as well.
In an expansion of the method, it is provided that the flow direction of the fluid and the longitudinal axis of the edge to be rounded off form an angle, in particular of 90°, thus further intensifying the removal of material.
It has proved to be especially advantageous to use a suspension of a grinding agent in oil as the erosive fluid. This suspension makes a greater removal of material possible, compared to the use of a polymeric plastic composition. In addition, cleaning of the workpieces once the method has been performed is simplified considerably. Finally, by the use of a suspension instead of a plastic composition, the fluid flow during the machining can be measured and monitored in a simple way. Since the fluid flow is correlated with the removal of material at the edges to be rounded off, the progress of workpiece machining can be monitored continuously on the basis of it. This is important above all in large- scale mass production of workpieces with extreme precision. The method of the invention is thus more economical and can be more widely used.
The object stated at the outset is also attained by an apparatus for performing the method of having a feed pump for the erosive fluid, and having a hydraulic communication between the feed pump and the component whose edge is to be rounded off. This apparatus has the advantage that because of the hydraulic communication of the feed pump and the component, a flow of the erosive fluid, above all in the region of the edge to be rounded off, can be built up, the consequence of which is the rounding off of the edge.
In a variant of the invention, it is provided that a body forming a gap with the edge to be rounded off is present, so that the flow speed of the erosive fluid is elevated in the region of the edge to be rounded off, compared to the average flow speed of the erosive fluid, thus speeding up the rounding off of the edge.
In an expansion of the invention, a collector device for catching the fluid is present, so that the erosive fluid does not reach the environment.
In another feature of the invention, the fluid is carried in closed loop circulation, thus reducing the consumption of erosive fluid.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages and features of the invention can be learned from the ensuing description, taken with the drawings, in which:
FIG. 1 is a cylindrical high-pressure fuel reservoir of the prior art, in fragmentary longitudinal section;
FIG. 2 is a cross section through a high-pressure fuel reservoir of the invention;
FIG. 3 is an X-Y graph illustrating the course of the contour of an edge rounded off according to the invention; and
FIG. 4 is a cross section through a blind bore injection nozzle rounded off according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, a high-pressure fuel reservoir 1 of the prior art is shown in fragmentary longitudinal section. The high-pressure fuel reservoir 1 has one or more connection stubs 2 , only one of which is shown in FIG. 1. A fastening tab 3 is also visible. The connection stub 2 has a bore 4 , which hydraulically connects the connection stub 2 to the storage chamber 5 . Severe mechanical stresses, which can cause breakage, occur in operation at an edge 6 that results from the intersection between the bore 4 and the storage chamber 5 . A tried and true means of abating these stresses is to round off the edge 6 . Because of the geometric conditions, this is possible only conditionally if at all with counterbores or the like. In any case, it involves high costs.
With the aid of the method of the invention, the rounding off can be done simply, effectively, economically, and quickly, with cycle times from 20 seconds to 200 seconds. To that end, instead of a closure screw 7 , a hydraulic communication, not shown, with a feed pump, also not shown, is established. The feed pump pumps an erosive fluid into the high-pressure fuel reservoir 1 that is carried away through the bore 4 . In the region of the edge 6 , because of the narrowing of the cross section, the flow speed of the fluid increases. Because of the high flow speed of the fluid, the edge 6 is rounded off by the erosive fluid. In the method of the invention, the removal of material at sharp edges is greater than at dull edges or faces. The inner wall of the high-pressure fuel reservoir 1 is not removed at all, because in accordance with Newton's condition of adhesion, the flow speed equals zero.
By adjusting the feed pressure of the feed pump, the flow speed and thus the removal of material as well can be varied. In practice, feed pressures between 50 bar and 140 bar have proved to be suitable.
In FIG. 2, a cross section through a further version of a high-pressure fuel reservoir 1 is shown. The connection stub 2 has a female thread 8 , into which a high-pressure line, not shown, can be screwed.
Since the bore 4 does not discharge into the storage chamber 5 at a right angle, the edge 6 is not equally sharp, viewed around the circumference of the bore 4 . It is sharpest at the point marked 9 , while it is markedly duller at the point marked 10 . After the rounding off according to the invention, the high-pressure fuel reservoir 1 was cut open in the plane marked A—A and examined. It was found that the edge 6 was rounded off the most at the point 9 , while the removal of material was less at the point 10 .
FIG. 3 shows the outcome of a measurement of the rounding off in the plane A—A after the method of the invention was applied at the sharp-edged point 9 . This graph shows the rounding contour of the sharp-edged point 9 in FIG. 2 (Y axis), plotted over the direction of motion of the measuring scanner (X axis). The radius of curvature R is 0.782 mm.
In FIG. 4, an injection nozzle 11 for a fuel injection system is shown, with a conical blind bore 12 . Via an injection port 13 , the fuel, not shown, passes from the blind bore 12 into the combustion chamber, also not shown. The conical blind bore 12 is adjoined by a frustoconical nozzle needle seat 14 .
On the left-hand side of FIG. 4, a transition between the blind bore 12 and the nozzle needle seat 14 in the prior art is shown in the form of an edge 16 . This edge 16 is created in the grinding of the nozzle needle seat 14 . Depending on the type of machining, the edge 16 can be either a sharp burr or a smooth edge.
On the right-hand side of FIG. 4, a transition 17 between a blind bore 12 and a nozzle needle seat 14 is shown that is rounded off according to the invention. To that end, an erosive fluid is pumped through the injection port 13 from the nozzle needle seat 14 . To achieve the highest possible flow speed in the region of the edge 16 or of the rounded-off transition 17 , in the rounding process a body 15 , which is for instance of ceramic and whose geometry is essentially equivalent to a nozzle needle, is introduced into the injection nozzle 11 . When the body 15 is lifted slightly from the nozzle needle seat 14 , the flow speed of the erosive fluid, not shown, is highest, because of the continuity equation, in the region of the edge 16 , that is, the rounded-off transition 17 . As a consequence, the most material is also eroded there, as a consequence rounding off is brought about above all there.
It has proved to be especially advantageous to use a suspension of a grinding agent in oil as the erosive fluid. Especially in conjunction with a pressure difference of from 50 bar to 140 bar, a removal of material thus results that is very much greater compared to the method known from the prior art. The method of the invention is thus more economical and can be used more widely.
In principle, edges of any type at outer contours or inner contours can be rounded off with the aid of a body 15 or without such a body, if the flow speed in the region of the edges 6 or 16 is high enough. Since the flow speed of the fluid needs to be high only in the region of the edges 6 or 16 , the removal of material performed by the erosive fluid at the other points of the workpiece as well as of the pump and other equipment is very slight. This lengthens the service life of all these elements.
The foregoing relates to preferred exemplary embodiment of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | A method and an apparatus for rounding off edges are proposed in which an erosive fluid is pumped over the edge to round off edges even at poorly accessible places or where the geometry is complicated. | 1 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a division of U.S. application Ser. No. 12/564,064 filed Sep. 22, 2009 which claims the benefit of U.S. Provisional Application No. 61/223,154, filed Jul. 6, 2009.
STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT
(Not Applicable)
REFERENCE TO AN APPENDIX
(Not Applicable)
BACKGROUND OF THE INVENTION
When a motor vehicle is involved in an accident, the standard automotive lap and shoulder belt restraint system, if properly used, provides a minimum level of protection from crash injury to the passengers or driver as required by Federal Motor Vehicle Safety Standard number 208—Occupant Crash Protection. This minimum level of protection is currently required for adult passengers and drivers who are either a 5.sup.th percentile adult female or a 50.sup.th percentile adult male. For persons who are smaller than a 5.sup.th percentile adult female, supplemental restraint devices are required to provide a minimum level of protection pursuant to Federal Motor Vehicle Safety Standard 213. There are currently no motor vehicle safety standards relating to adults larger than a 50.sup.th percentile male adult, or to a pregnant woman of any size and her unborn child(ren).
The purpose of the “Method For Supplemental Automotive Restraint For Pregnant Women” (Method/Device) is to provide enhanced protection for the pregnant mother and her unborn child(ren).
There are several categories of injuries that occur to lap and shoulder belted occupants in motor vehicle crashes. One category results from violent contact with the steering wheel, the inner door surfaces and related components, the dashboard area and related components, the windshield, side windows and their related frames, and other objects. A second category involves injuries caused by inflating air bags, and a third category involves injuries caused by the lap and shoulder belts. These belt-induced injuries are commonly referred as “Seat Belt Syndrome”. “Seat Belt Syndrome” injuries are signified by skin abrasions of the neck, chest, and abdomen, which indicate internal injury in approximately 30% of cases. Neck abrasions are associated with injuries to the carotid artery, larynx, and cervical spine. Chest abrasions are associated with fractures of the sternum, ribs, and clavicles, and injuries to the lungs, heart and thoracic aorta. Abdominal abrasions are associated with mesenteric tears, bowel perforation and hematoma, injuries to the abdominal aorta and injuries to the spine, spinal cord, and pelvis..sup.i These injuries are exacerbated when the lap belt slips up over the pelvis and into the lower abdominal cavity. This is commonly referred to as “submarining”, and it is the natural tendency and a frequent occurrence in motor vehicle crashes and at other times. .sup.iHayes, Conway, Walsh, Coppage, & Gervin, “Seat Belt Injuries: Radiologic and Clinical Correlation”, Department of Radiology, Medical College of Virginia, Radiographics, January 1991, 11(1):23-36
There are two categories of forces between the seat belts and the body of the person. The first involves the static forces that are intended to hold the belts in place during normal vehicle operations. These static forces are typically provided by a seat belt retractor or similar device. These forces are minimal in the absence of a crash or other abrupt motion change (acceleration) of the vehicle, and are associated primarily with the comfort of the passenger. They are inconsequential in causing injury to the passenger provided that they maintain the belts in the proper position prior to the crash.
The second category of force between the seat belts and the body of the person involves the dynamic forces between the surface of the body and the lap and shoulder belts as required to restrain the body in the vehicle during the abrupt motions of crash or other event. These forces exist only when the vehicle is undergoing a crash or other abrupt motion change (acceleration).
Seat Belt Syndrome injuries result from this second category of dynamic forces. These forces are applied to the limited area of direct contact between the belts and the surface of the body. The application of these high dynamic forces to the limited area of contact between the belts and the person's body causes high stresses and strains in various parts of the body, which are the root causes of Seat Belt Syndrome injuries.
The mechanisms of injury to the fetus are less well documented, but the risk of injury is clearly extended to the unborn child. Of pregnant women who are treated for injury in hospital emergency departments, “Motor Vehicle occupant injuries were the leading mechanism of emergency department injury-related visits . . . . Pregnant women with an injury-related emergency department visit were more likely than non-injured pregnant women to experience pre-term labor, placental abruption, and cesarean delivery..sup.ii .sup.iiWeiss, Sauber-Schatz and Cook, “The Epidemiology of Pregnancy-Associated Emergency Department Injury Visits and their Impact on Birth Outcomes”, Accident Analysis and Prevention, Volume 40, Issue 3, May, 2008, pp. 1088-1095.
The unborn child is at risk because the mother's abdomen provides limited protection against objects that impinge on the abdomen, such as the steering wheel, lap and shoulder belts, air bag restraints, door handles and other objects and surfaces within the vehicle that are likely to contact and apply force to the mother's body in both accident and non-accident situations. In particular, the lap and shoulder belts, steering wheel and air bags are designed to protect the mother. They also provide some protection to the fetus, but in addition, all three pose additional side effect risks of injury to the fetus.
BRIEF SUMMARY OF THE INVENTION
The purpose of the “Method/Device” is to reduce the likelihood of injury to a pregnant mother and her unborn child(ren) during maneuvering, crash, or other non-impact event of a motor vehicle while the mother is driving or riding in the vehicle by preventing direct contact between the lap and shoulder belts, air bags, steering wheel and other objects with the abdomen; directing lap belt forces away from the abdomen and into the pelvis and ribs to the extent feasible; directing shoulder belt forces away from the abdomen and into the pelvis and ribs to the extent feasible; and applying the forces required to restrain the abdomen through an appropriately contoured and padded interior surface of the “Abdominal Bridge/Shell” protective structure.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 illustrates the general shape and arrangement of the several integral parts of the Method/Device, including the “Abdominal Bridge/Shell”, “Breast Plate”, “Pelvic Yoke” and “Crotch Post”, “Side Wings”, and “Shoulder Belt Retainer”.
FIG. 2 illustrates a frontal view of the proper use of the Method/Device with the conventional lap and shoulder belts that are required to be installed in the vehicle by Federal Motor Vehicle Safety Standard No. 208, Occupant Crash Protection.
FIG. 3 illustrates a side view of the proper use of the Method/Device with the conventional lap and shoulder belts that are required to be installed in the vehicle by Federal Motor Vehicle Safety Standard No. 208, Occupant Crash Protection, including a representation of the internal spacing/padding elements used to accommodate the changing anthropometry of the pregnant woman during her pregnancy.
FIG. 4 illustrates a side-frontal view of the proper use of the Method/Device with the conventional lap and shoulder belts that are required to be installed in the vehicle by Federal Motor Vehicle Safety Standard No. 208, Occupant Crash Protection.
In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific term so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.
DETAILED DESCRIPTION OF THE INVENTION
Patent application Ser. No. 12/564,064 filed Sep. 22, 2009, Publication number US 2011/0001311 A1, the above claimed priority application, and U.S. Provisional Application No. 61/223,154, filed Jul. 6, 2009 are hereby incorporated in this application by reference.
The “Method/Device” provides an enhanced level of protection to both the mother and her unborn child(ren) as follows:
1. Lap Belt Forces. The lap belt is intended to be positioned low on the torso such that lap belt forces are directed primarily into the area of the pelvic iliac crests. There is a common and natural tendency, both during crash events and at other times, for the lap belt to move above the area of the iliac crests to a position that allows penetration of the lower abdomen and application of lap belt forces directly to the abdomen. The “Method/Device” provides a geometric configuration and structure to help prevent the “Method/Device” from moving upward on the woman's body, maintain the lap belt below the abdomen, direct lap belt forces downward and aft to the mother's pelvic iliac crests and pubic bony structures through the “Pelvic Yoke” and integral “Crotch Post”, and direct the upper and rotational components of these forces to the “Abdominal Bridge/Shell” for transmission over the abdomen to the “Breast Plate”.
2. Shoulder Belt Forces. The shoulder belt is intended to be positioned above the abdomen and below the neck to avoid direct application of shoulder belt forces to the upper abdomen and neck. There is a common and natural tendency, both during crash events and at other times, for the shoulder belt to move both downward into the upper abdomen and/or upward into the area of the neck. The “Method/Device” provides a geometric configuration and structure to help maintain the shoulder belt above the abdomen and below the neck (“Shoulder Belt Retainer”), direct shoulder belt forces to the mother's sternum and ribs through the contoured padded “Breast Plate” designed to provide a relatively even distribution of shoulder belt forces over the surface of the torso, and direct the lower and rotational components of these forces to the “Abdominal Bridge/Shell” for transmission over the abdomen to the “Pelvic Yoke”.
3. Submarining. When the lap belt applies the aft directed crash forces to the iliac crests, which is the intended function of the lap belt, it naturally causes, in combination with the forward directed, inertial forces caused by the restraint of the legs, a top-aft rotational torque acting on the pelvis that tends to induce submarining of the pelvis under the lap belt with resulting injury to the abdomen, spine and other body areas. The “Method/Device” provides a load path directly to the pubis by means of the “Crotch Post” to react the top-aft rotational torque on the pelvis to help prevent submarining of the pelvis under the lap belt, and direct the upper and rotational components of these forces to the “Abdominal Bridge/Shell” for transmission over the abdomen to the “Breast Plate”.
4. Protective “Abdominal Bridge/Shell”. It is common in both crash and non-crash situations for the lap and shoulder belts, air bags, steering wheel, side panels and related components, dashboard and related components, and other objects to contact, penetrate and/or distort the abdomen. The “Method/Device” provides a protective “Abdominal Bridge/Shell” structure over the abdomen to protect the abdomen from contact, penetration and/or distortion by objects such as the lap and shoulder belts, air bags, steering wheel, side panels and related components, dashboard and related components, and other objects, and to bridge the lap & shoulder belt crash forces over the abdomen and to either the “Pelvic Yoke” or the “Breast Plate”.
5. “Abdominal Bridge/Shell” Catchment. There is a natural tendency for the abdomen to move forward in a frontal crash and attempt to extrude itself between the lap and shoulder belts. This causes extreme distortion and high potential for injury to the abdominal organs, spine and ribs. The “Method/Device” provides an appropriately contoured and padded catchment chamber integral to the “Abdominal Bridge/Shell” to catch and restrain the abdomen in a contoured protective shell that provides a relatively even application of the forces required to restrain the abdomen and reduce shape deformation of the abdominal organs, spine, and ribs during the event.
6. “Side Wings”. There is a natural tendency for the door or other vehicle side structure to impact the side of the body particularly during side and/or rollover crashes. The “Method/Device” provides protective “Side Wing” structures to provide enhanced protection for the pelvis, abdomen and lower ribs in side impact and rollover crashes and other incidents.
7. “Filler/Padding Elements”. The shape of the woman's body progressively changes during the pregnancy. The “Method/Device” provides appropriate internal “Filler/Padding Elements” to accommodate the changing anthropometry of the woman's body during pregnancy and prevent excessive distortion of the spine, abdomen and uterus.
8. Internal Padding. The “Method/Device” provides a relatively even distribution of all residual crash forces to the surface of the mother's body through the contoured and padded inner surfaces of the “Method/Device”.
PRIOR ART
There is a wealth of prior art relating to safety belts in various types of vehicles, including Federal Motor Vehicle Safety Standard Numbers 208, 209, and 213. This “Method/Device” augments and enhances the protective capabilities of these devices.
In the patent literature, several devices are disclosed relative to belt-type restraint systems for motor vehicles, including several (such as References 5 and 6) that utilize a crotch strap to prevent the pelvis from submarining under the lap belt, which is its natural and highly injury producing tendency during crashes. Such crotch straps are highly effective in preventing submarining of the pelvis under the lap belt, and they are in common usage in military applications, competitive racing vehicles, and child and infant restraint systems. They are not in common usage by adults in passenger vehicles, and the level of performance they provide is not required under the applicable Federal Motor Vehicle Safety Standard #208 because the public has shown great resistance to the usage of such devices, and it is judged that the effect of crotch strap installation would be an undesirable reduction in seat belt usage rates. The “Method/Device” provides protection from pelvic submarining under the lap belt without a crotch strap by use of a “Crotch Post” which prevents pelvic submarining and provides a direct load path for the application of lap belt crash forces to the pubis portion of the pelvis. It functions as an integral part of the “Pelvic Yoke” which provides a second direct load path for the application of lap belt crash forces to the pelvis through the iliac crests. The integral “Pelvic Yoke” and “Crotch Post” direct the rearward upper components of these forces into the “Abdominal Bridge/Shell”, which carries them over the abdomen and reacts them against the bony ribs through the “Breast Plate”.
There are also several patents, such as References 3 and 4, which deal with cushion or pillow like interventions of various types. These devices provide little or no protection against pelvic submarining and extreme distortion of the abdomen and spine. In addition they would provide very limited protection of the abdomen in crash impact situations because in the absence of a semi-rigid shell or other protective structure, the belts will simply knife through the pillows and produce the same types of injuries seen with conventional lap and shoulder belts. The lower steering wheel would behave in the same way.
Perhaps the closest prior art is illustrated in References 1 and 2, wherein a structural shell is positioned over the abdomen, and the lap belt forces are directed into the shell. In this configuration, virtually all lap belt forces would be transmitted directly into and through the abdomen in the area of the uterus/fetus. Furthermore, the high location of the lap belt would increase the tendency of the pelvis to rotate and submarine under the lap belt resulting in increased injury potential for both the mother and her unborn child(ren), This is opposite of the design intent and operation of the “Method/Device”, which directs these forces away from the abdomen and uterus, and into the bony pelvis structure, and directs the upper rearward components of these forces to the “Abdominal Bridge/Shell” for transmission over the abdomen to the “Breast Plate”.
The “Method/Device” directs virtually all of the lap belt forces required to restrain the hips and legs into the pelvis, and the upper components of these forces are bridged over the abdomen into the “Breast Plate” where they are reacted into the lower rib structures through the padded contoured surface of the “Breast Plate”. The forces required to restrain the upper thorax, neck, head and arms are directed primarily through the “Breast Plate” into the ribs. In the area above the “Breast Plate”, some of these forces are applied by the shoulder belt directly to the area of the upper ribs, clavicles, and neck, which is the normal and intended function of the shoulder belt. The primary force directed into the abdomen is the force required to restrain the abdomen itself, and there is no way to divert these forces away from the abdomen since they are required to react the body forces of the inertial mass of the abdomen itself.
PREFERRED EMBODIMENT
In the preferred embodiment, the “Method/Device” is constructed primarily of inner and outer layers of fiber reinforced plastic to achieve the required strength and flexibility to provide a high level of supplemental protection to the mother and child in a crash. The “Pelvic Yoke” and “Crotch Post” will be composed of dense plastic foam or other material to reinforce and maintain spacing between the inner and outer layers of the “Abdominal Bridge/Shell” to add the structural rigidity required to carry the high bending loads that will occur in this area during a crash. “Filler/Padding Elements” materials consist of a variety of plastic foams, including semi rigid foams for the fill components, firm and highly damped flexible foams for the energy absorbing layers, and medium to light firmness foam for inner comfort and spacing layers.
Many materials could be used for this application, but care must be exercised to assure sufficient strength, flexibility and energy absorption characteristics to provide a high level of supplemental protection to the mother and child in a crash.
This detailed description in connection with the drawings is intended principally as a description of the presently preferred embodiments of the invention, and is not intended to represent the only form in which the present invention may be constructed or utilized. The description sets forth the designs, functions, means, and methods of implementing the invention in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and features may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention and that various modifications may be adopted without departing from the invention or scope of the following claims. | A Supplemental Automotive Restraint System for Pregnant Women has a protective shell structure with integral “Pelvic Yoke and Crotch Post”, “Breast Plate”, structural “Abdominal Bridge/Shell” over the abdomen between the “Pelvic Yoke” and the “Breast Plate”, “Shoulder Belt Retainer”, and appropriate padding and fill material, all of which work in conjunction with the standard automotive Type II lap and shoulder belt restraint system as required to be installed in all new passenger cars manufactured for sale in the United States by Federal Motor Vehicle Safety Standard No. 208 (FMVSS 208). The purpose of the “Supplemental Automotive Restraint System for Pregnant Women” is to reduce the likelihood of injury to a pregnant mother and her unborn child during maneuvering, crash, or other non-impact event of a motor vehicle while the mother is driving or riding in the vehicle. | 1 |
BACKGROUND
Location-aware devices can provide maps to users based on the users' location requests. Additionally, location-aware devices may provide additional information pertaining to locations based on location services. However, location services are limited due to stale information (e.g., information not being updated) and/or coverage of information (e.g., the information available is limited in terms of scope, specificity, etc.).
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a diagram illustrating an exemplary environment in which an exemplary embodiment of a user profile-based assistance communication system may be implemented;
FIGS. 1B-1E are diagrams illustrating an exemplary process for providing user profile-based user assistance;
FIG. 2 is a diagram illustrating exemplary components of a device that may correspond to one or more of the devices depicted in FIGS. 1A-1E ;
FIG. 3 is a diagram pertaining to the setting-up of a user profile;
FIG. 4 is a diagram illustrating an exemplary user profile stored by user profile storage depicted in FIGS. 1A-1E ;
FIG. 5 is a diagram illustrating an exemplary graphical user interface of a user's profile;
FIG. 6 is a diagram pertaining to the selection process of user profiles;
FIGS. 7A-7C are flow diagrams illustrating an exemplary process for providing user profile-based assistance; and
FIGS. 8A and 8B are flow diagrams illustrating another exemplary process for providing user profile-based assistance.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The following detailed description refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements. Also, the detailed description does not limit the invention.
According to an exemplary embodiment, a profile-based assistance communication system permits users to ask for help from other users based on user profiles. According to an exemplary embodiment, the user profile may include information about the user
FIG. 1 is a diagram illustrating an exemplary environment 100 in which an exemplary embodiment of a profile-based assistance communication system may be implemented. As illustrated in FIG. 1 , environment 100 may include a service provider network (SPN) 105 and user devices 125 - 1 through 125 -T (referred to individually as user device 125 or collectively as user devices 125 ). Service provider network 105 may include, among other devices, an assistance device 110 , a user profile storage 115 , and a user profile storage manager 120 .
The number of devices and networks, and the configuration in environment 100 is exemplary and provided for simplicity. In practice, according to other embodiments, environment 100 may include additional devices, fewer devices, different devices, and/or differently arranged devices, than those illustrated in FIG. 1 . Additionally, according to another embodiment, environment 100 may include additional networks, fewer networks, and/or differently arranged networks, than those illustrated in FIG. 1 .
Also, according to another embodiment, one or more functions and/or processes described as being performed by a particular device may be performed by a different device or a combination of devices. For example, according to an embodiment, a function or a process described as being performed by two or more devices may be performed by a single device. Conversely, according to another embodiment, a function or a process described as being performed by a single device may be performed by two or more devices or by a different device. By way of example, one or more functions and/or processes described as being performed by user profile storage manager 120 may be performed by assistance device 110 or vice versa. Also, user profile storage manager 120 may be combined with user profile storage 115 . Environment 100 may include wired and/or wireless connections among the devices illustrated.
Service provider network 105 may include a network that distributes or makes available a service, such as, a user assistance service. Service provider network 105 may also include a network that distributes or makes available mobile service, Internet service, and/or a television service. Service provider network 105 may include a satellite-based network and/or a terrestrial-based network. For example, service provider network 105 may include a wireless network (e.g., a cellular network, a non-cellular network, a mobile network, a 3 rd Generation (3G) network, a 4 th Generation (4G) network) in combination with a Voice over Internet Protocol (VoIP) network, a packet-switched network, a television distribution network, and/or the Internet. Although not illustrated, service provider network 105 may include, for example, billing devices, security devices, etc.
Assistance device 110 may service requests for assistance associated with a user profile-based assistance service. Assistance device 110 receive assistance requests from users and select user profiles associated with the other users that may be most likely to offer assistance. Assistance device 110 provides the selected user profile(s) to the user seeking assistance to allow the user to select a user profile and receive assistance from that other user. Assistance device 110 is described further below.
Assistance device 110 may be implemented by one or multiple network devices. For example, the network device(s) may include a computational device (e.g., a computer, a server, an Application server, a web server, a peer device, etc.) or a cloud-computing service. Assistance device 110 may provide user interfaces to users. Assistance device 110 will be described further below.
User profile storage 115 may store user profile information. According to an exemplary embodiment, the user profile information may be stored as a database (e.g., a relational database, a distributed database, a document-oriented database, or other type of suitable database). According to other embodiments, the user profile information may be stored as a data structure (e.g., files, records, arrays, lists, objects, etc.). The user profile information may also be indexed based on one or more types of user profile information types (e.g., location where user lives and/or works, age of user, etc.). User profile storage 115 may be implemented by one or multiple network devices. For example, the network device(s) may include a storage device (e.g., a hard disk or other tangible storage medium) and/or a computational device (e.g., a computer, a server, etc.).
Each user profile may include information pertaining to a user. For example, according to an exemplary embodiment, a user profile may include information indicating a name of the user, a photo of the user, information indicating a location of the user (e.g., city, state, etc.), information indicating the profession of the user (e.g., policeman, professor, student, teacher, plumber, etc.), information indicating the number of years the user has lived and/or worked in a particular area (e.g., 10 years, 3 years, 2 months, etc.), and information indicating a user rating (e.g., a numerical value, a star rating, etc.). For example, the user rating may indicate an average rating by other users that corresponds to an evaluation of the user's assistance. According to another embodiment, a user profile may include additional, fewer, or different types of information. By way of example, the user profile may include information pertaining to a user's availability (e.g., days (e.g., Monday-Friday, etc.), times (e.g., between 6 p.m.-11 p.m., evenings, mornings, etc.), dates, (January-August), etc.), a user's choice of communication to provide assistance (e.g., telephone, video-telephony, etc.), a user's choice of notification (e.g., via television service, via mobile service, via Internet service), a user category of expertise or knowledge relative to a particular geographic location (e.g., restaurants, shopping, driving, etc.), and/or a user's driving history (e.g., number of years driving in a particular geographic location).
User profile storage manager 120 may manage user profile storage 115 . For example, user profile storage manager 120 may control the creation, maintenance, and use of user profile information stored by user profile storage 115 . User profile storage manager 120 may also permit access and retrieval of user profiles based on queries. User profile storage manager 120 may be implemented by one or multiple network devices. For example, the network device(s) may include a computational device (e.g., a computer, a server, an application server, a database server, etc.) that includes a database management system that supports, among other things, a data model and a query language, and controls data access, data integrity, etc. User profile storage manager 120 will be described further below.
User device 125 may include, for example, a mobile device, a handheld device, a tablet device, or a vehicle-based device. For example, user device 125 may take the form of a wireless phone (e.g., a smart phone, a cell phone, an iPhone™ device, etc.), an Internet-access device (e.g., a netbook, an iPad™ device, etc.), or a vehicular communication system.
User device 125 may have location-aware capability. A variety of technologies or techniques (e.g., Global Positioning System (GPS), cellular positioning methods (e.g., triangulation, etc.), local positioning methods (e.g., Bluetooth, IEEE 802.11, WiFi, Ultra Wide Band (UWB), etc.)) exist to identify a geographic position associated with a user or a user device. However, these technologies may provide the user's geographic position or a geographic position of the user device with different degrees of precision or accuracy. While, a GPS is a popular technology that enables the user or the user device to obtain geographic positional information, the GPS typically does not work well inside buildings or underground due to the absence of line of sight to satellites and attenuation and scattering of signals caused by roofs, walls, and other objects. In this regard, other technologies, such as, for example, an indoor positioning system (IPS) may be utilized. Thus, while the description that follows may describe embodiments that utilize a GPS, other technologies or techniques may be utilized to obtain the geographic position of the user or the user device. User device 125 may be capable of communicating with one or more devices in service provider network 105 .
FIGS. 1B-1E are diagrams illustrating an exemplary process for providing profile-based user assistance. According to an exemplary scenario, assume that a user of user device 125 - 1 (not illustrated) is driving in his/her car and wishes to acquire information pertaining to a destination (e.g., at downtown Boston). In this example, user device 125 - 1 may take the form of a vehicular communication system or a mobile device. For example, the vehicular communication system may include a GPS, a wireless adapter (e.g., a 3G wireless adapter, a 4G wireless adapter, etc.), an on-board speaker and microphone system, and a display (e.g., a touch display). The vehicular communication system may include a video camera and/or speech recognition system. The vehicular communication system may include a vehicle-to-vehicle, profile-based assistance application. The vehicle-to-vehicle, profile-based assistance application may permit a user to communicate with other users and permit the user to ignore, accept, start, and end a vehicle-to-vehicle communication. According to an exemplary implementation, the vehicle-to-vehicle, profile-based assistance application may include a safety feature that requests the user to fasten his/her seatbelt before using the system.
According to an exemplary embodiment, the vehicle-to-vehicle, profile-based assistance application may permit the user to record, play, stop, rewind, loop, delete, fast-forward, etc. a conversation with another user. Additionally, according to an exemplary embodiment, the vehicle-to-vehicle, profile-based assistance application may permit the user to send geographic location information (e.g., a GPS screenshot, address information, a map, and/or other location information) of the user's location to the other user offering assistance.
Referring to FIG. 1B , assume the user uses voice command (e.g., the user says “help”) or presses a help button (e.g., an icon) displayed on user device 125 - 1 via a graphical user interface (GUI). The user is then prompted to provide a destination. In this example, the user indicates downtown Boston. According to an exemplary embodiment, user device 125 - 1 generates a help request 140 that includes the destination information.
According to another embodiment, the user may have already specified a destination (e.g., via a GPS system). According to such circumstances, when the user invokes user profile-based assistance, the destination information may be captured and the user may not need to be prompted for the destination.
According to other implementations, the user may be prompted to enter additional information that further specifies the type of assistance. According to an exemplary embodiment, user device 125 - 1 generates a help request 140 that includes the destination information and the type of assistance. By way of example, the GUI may provide different categories of assistance (e.g., location assistance, monetary assistance, restaurant assistance, shopping assistance, lodging assistance, etc.). For example, location assistance may provide assistance to a user regarding specifics of a particular destination. For example, if a user is traveling to a park, the GPS information may provide the location of the park. However, the GPS information may not indicate where the main entrance is to the park or whether there is anywhere to go fishing in the park. The user may contact a friend or a relative to find out this information. However, the friend or relative may not have ever visited the park. Further, if the user is in a vehicle, the user may be less inclined to stop and ask a stranger for particular information.
According to other scenarios, the user may be interested in knowing which parking lot to park in a ski resort or the user may be in a stadium and wishes to know where the expo is located and which way to travel. Monetary assistance may provide, for example, assistance to a user regarding saving money. For example, the user may wish to park in a parking garage but does not know which one in the vicinity has the best rate. Additionally, for example, the restaurant assistance, the shopping assistance, and the lodging assistance may provide assistance to a user by providing recommendations to restaurants, stores or shopping centers, lodging (e.g., motels, hotels, inns, bed-and-breakfasts, etc.), etc. The description of these categories is not intended to be exhaustive and additional categories may be implemented (e.g., repair garage, tours of the area, etc.). Additionally, a category may include sub-categories that further narrow the type of assistance. By way of example, monetary assistance may include sub-categories, such as parking, food, etc. Additionally, a user may specify other types of information pertaining to help request 140 . For example, the user may indicate a priority level for help request 140 , such as urgent, normal, etc. As an example, a user may wish to assign an urgent priority level for help request 140 when the user is pressed for time (e.g., running late for an appointment, etc.) or some other urgent circumstance exists.
As illustrated in FIG. 1B , help request 140 may be transmitted from user device 125 - 1 to service provider network 105 . Assistance device 110 may receive help request 140 and select one or more user profiles 145 based on the information included in the help request 140 . For example, assistance device 110 may generate a query and transmit the query to user profile storage manager 120 in which user profiles stored by user profile storage 115 may be accessed and selected. The query may include the destination (e.g., in this example, is downtown Boston), and the type of assistance (e.g., monetary assistance, parking). Assistance device 110 may receive a query response that includes one or more user profiles.
According to an exemplary embodiment, assistance device 110 may select the best user profile(s) included in the query response based on help request 140 and the information included in each user profile. For example, according to an exemplary embodiment, assistance device 110 may include a ranking algorithm that ranks user profiles based on the area where the user lives, the amount of time the user has lived and/or worked in the area, the profession of the user, the user rating, and the destination. According to other embodiments, assistance device 110 may use additionally, fewer, or different types of information. For example, assistance device 110 may use the type of user assistance (e.g., in this example, monetary assistance, parking), the availability of the user, whether the user is also currently driving, and/or other information included in a user profile.
According to an exemplary embodiment, the ranking algorithm may use a weighting system in which each type of information is assigned a weighted value. According to an exemplary implementation, some types of information may be afforded a higher weight relative to other types of information. By way of example, the length of time the user lived and/or worked in the area may be afforded a greater weight than the profession of the user. According to an exemplary implementation, the weight assigned to each type of user profile information may also be dependent on the information itself. For example, a user that has lived in the area for 30 years may be assigned a greater weighted value for this type of information than a user that has lived in the area only 10 years. According to another example, a user whose profession is a doctor, a policeman, a teacher, or an attorney may be assigned a greater weighted value for this type of information than a user that is a student, a nurse, etc.
According to an exemplary embodiment, assistance device 110 may select the best user profile candidates to offer assistance to the user based on the ranking algorithm. According to an exemplary implementation, assistance device 110 may also filter user profile candidates based on whether a user is active with service provider network 105 . For example, if a user does not have a mobile device turned on, is not driving, and is not watching television then service provider network 105 may remove a user profile based on the user's unavailability. Alternatively, according to an exemplary embodiment, assistance device 110 may not determine the availability of a user until an assistance request for that user is received, as described below.
Referring to FIG. 1C , once assistance device 110 selects the best user profiles, assistance device 110 sends a help response 150 to user device 125 - 1 . The user may then review the user profiles. For example, since the user is driving, the user profiles may be displayed and the vehicle communication system may read the user profiles to the user. Alternatively, the user may navigate through the user profiles via a GUI displayed by the touch display. In this example, the user selects one of the user profiles (e.g., vocally or via touch display) and user device 125 - 1 receives the user profile selection 155 .
Referring to FIG. 1D , user device 125 - 1 generates and transmits an assistance request 160 that is sent to user device 125 -T via service provider network 105 . In this example, the user of user device 125 -T is also driving and has a vehicular communication system that service provider network 105 recognizes as active. Service provider network 105 may route assistance request 160 to the vehicular communication system. Alternatively, assistance request 160 may be routed to another type of user device 125 (e.g., a smart phone, etc.).
As previously described, a user profile may include information pertaining to a user's choice of notification. For example, the user may indicate that he/she may be notified via a particular device (e.g., vehicular communication system, mobile device) and/or via a particular service (e.g., mobile service, television service, etc.). Service provider network 105 may consider these parameters when routing assistance request 160 . Additionally, service provider network 105 may also consider whether the user is active with respect to service provider network 105 . For example, when the user's vehicle is turned-off, service provider network 105 would not route assistance request 160 to the vehicular assistance communication. Similarly, if the user's mobile device is turned-off, service provider network 105 would not route assistance request 160 to the user's mobile device. As previously described, a user may receive profile-based communications via various services (e.g., mobile, Internet, television). In this regard, according to an exemplary implementation, service provider network 105 may select a user device that is currently active.
In this example, the user of user device 125 -T is alerted (e.g., an auditory cue (e.g., telephone ring, etc.), a visual cue (e.g., an image indicating that an assistance request has been received is displayed on the touch display)) to the receipt of assistance request 160 . The user of user device 125 -T has the option to accept the request or ignore it. In this example, the user of user device 125 -T accepts assistance request 160 vocally (e.g., a voice command (e.g., “answer,” “accept,” etc.)) or presses an icon on the touch display (e.g., an answer button, etc.) and an assistance response 165 is sent to user device 125 - 1 . Thereafter, a live one-to-one conversation may begin. The communication link between the users may stop when either user terminates it vocally (e.g., voice command) or pressing an icon on the touch display. During the conversation, either user may record the conversation using a voice command or via the touch display. The user may also have available other commands, such as pause, play, stop, rewind, fast-forward, loop, etc.
According to an exemplary embodiment, during recording, the conversation may be stored on user device 125 and/or streamed to assistance device 110 or some other network device (not illustrated) in service provider network 105 . As previously described, a user may play, replay, loop, etc., a recording of a conversation, which may be stored on user device 125 , assistance device 110 , or another network device in service provider network 105 (e.g., a server, a computer, a web server, an application server, a peer device, etc.).
According to an exemplary embodiment, the communication link between users in the vehicle may be based on a VoIP telecommunication service (e.g., offered by the service provider of service provider network 105 ) through a radio wave channel of a wireless network. According to other embodiments, the communication link between users in the vehicle may be based on other protocols, networks, etc.
According to an exemplary embodiment, the user seeking assistance may send geographic location information (e.g., a GPS screenshot, address information, a map, and/or other location information) of the user's location to the other user offering assistance, as illustrated in FIG. 1E . By way of example, according to this scenario, the vehicular communication system may provide a GPS map via the touch display and the user may select a location on the GPS map to send to the other user. The other user may receive the location information via the vehicular communication system. For example, the location of the user may be indicated on the other user's GPS map. According to other implementations, the GPS location of the user may automatically be included in assistance request 160 . The user may be able to set a user preference pertaining to this feature.
According to an exemplary embodiment, after completion of the communication, the user seeking assistance may be prompted to rate the performance of the user offering assistance. By way of example, the user may rate the other user's performance based on a numerical scale (e.g., 1-10) or some other form of rating system via voice command or via the touch display. The rating of the other user may be applied (e.g., averaged) to other ratings for the other user and included in the other user's user profile. Additionally, or alternatively, the user may be prompted to rate other aspects of the user's experience relative to the other user (e.g., friendliness, usefulness, eagerness or willingness to help other people, etc.). The rating of these aspects may also be included in the other user's profile.
The processes and messages illustrated in FIGS. 1B-1E and described are exemplary. According to other embodiments, different processes and/or messages may be implemented. For example, depending on user device 125 of the user requesting assistance or user device 125 of the user providing the assistance, different processes and/or messages may be implemented. By way of example, service provider network 105 (e.g., assistance device 110 ) may send an assistance request to another user via a set top box or other type of SPN television service interface device. For example, an overlay may be generated that indicates an assistance request has been received. The assistance request may include a telephone number or permit video conferencing via the television (e.g., assuming previous set-up and equipment (e.g., video camera, etc.). The other user may ignore or accept the assistance request via a remote control device of the television or the set top box. According to another example, the other user may be using Internet service on his/her desktop computer or other type of user device (e.g., mobile device, netbook, etc.), and an assistance request may be routed to the other user.
FIG. 2 is a diagram illustrating exemplary components of a device 200 that may correspond to one or more of the devices in environment 100 . For example, device 200 may correspond to one or more devices in service provider network 105 and user device 125 . As illustrated, according to an exemplary embodiment, device 200 may include a processing system 205 , memory/storage 210 including an application 215 , a communication interface 220 , an input 225 , and an output 230 . According to other embodiments, device 200 may include fewer components, additional components, different components, and/or a different arrangement of components than those illustrated in FIG. 2 and described herein.
Processing system 205 may include one or multiple processors, microprocessors, data processors, co-processors, application specific integrated circuits (ASICs), controllers, programmable logic devices, chipsets, field-programmable gate arrays (FPGAs), application specific instruction-set processors (ASIPs), system-on-chips (SOCs), central processing units, and/or microcontrollers to interpret and execute instructions. Depending on the type of processing system 205 , processing system 205 may be implemented as hardware, a combination of hardware and software, may include a memory (e.g., memory/storage 210 ), etc.
Processing system 205 may control the overall operation or a portion of operation(s) performed by device 200 . Processing system 205 may perform one or multiple operations based on an operating system and/or various applications (e.g., application 215 ). Processing system 205 may access instructions from memory/storage 210 , from other components of device 200 , and/or from a source external to device 200 (e.g., a network, another device, etc.).
Memory/storage 210 may include one or multiple memories and/or one or multiple other types of tangible storage mediums. For example, memory/storage 210 may include one or multiple types of memories, such as, random access memory (RAM), dynamic random access memory (DRAM), cache, read only memory (ROM), a programmable read only memory (PROM), a static random access memory (SRAM), a single in-line memory module (SIMM), a dual in-line memory module (DIMM), a flash memory, and/or some other type of memory. Memory/storage 210 may include a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optic disk, a solid state disk, etc.) or a floppy disk (e.g., a zip disk, etc.) and a corresponding drive, a tape, a Micro-Electromechanical System (MEMS)-based storage medium, and/or a nanotechnology-based storage medium. Memory/storage 210 may include drives for reading from and writing to the tangible storage medium.
Memory/storage 210 may be external to and/or removable from device 200 , such as, for example, a Universal Serial Bus (USB) memory stick, a dongle, a hard disk, mass storage, off-line storage, or some other type of storing medium (e.g., a compact disk (CD), a digital versatile disk (DVD), a Blu-Ray® disk (BD), etc.). Memory/storage 210 may store data, application(s), and/or instructions related to the operation of device 200 .
Application 215 may include software or a program that provides various services and/or functions. For example, with reference to assistance device 110 , application 215 may include a help-assistance application or program based on the processes and/or functions described herein. Additionally, for example, with reference to user profile storage manager 120 , application 215 may include a database management application or database management program that manages user profiles stored by user profile storage 115 . Additionally, for example, with reference to user device 125 , application 215 may include a user profile-based assistance application or program for permitting user profile-based assistance communication, user interfaces, etc., to a user.
Communication interface 220 may permit device 200 to communicate with other devices, networks, systems, etc. Communication interface 220 may include one or multiple wireless interfaces and/or wired interfaces. Communication interface 220 may include one or multiple transmitters, receivers, and/or transceivers. Communication interface 220 may operate according to one or multiple protocols, standards, and the like.
Input 225 may permit an input into device 200 . For example, input 225 may include a keyboard, a mouse, a camera, a scanner, a microphone, a display, a touchpad, a button, a switch, an input port, speech recognition logic, fingerprint recognition logic, a web cam, a video camera, and/or some other type of visual, auditory, tactile, etc., input component. Output 230 may permit an output from device 200 . For example, output 230 may include a speaker, a display, a light, an output port, and/or some other type of visual, auditory, tactile, etc., output component.
Device 200 may perform processes in response to processing system 205 executing instructions (e.g., application 215 ) stored by memory/storage 210 . By way of example, the instructions may be read into memory/storage 210 from another memory/storage 210 or from another device via communication interface 220 . The instructions stored by memory/storage 210 may cause processing system 205 to perform one or more processes described herein. Alternatively, for example, according to other implementations, device 200 may perform one or more processes described herein based on the execution of hardware (processing system 205 , etc.), the execution of hardware and firmware, or the execution of hardware, software, and firmware.
As previously described, according to an exemplary embodiment, a profile-based assistance communication system permits users to ask for help from other users based on user profiles. According to an exemplary embodiment, the user profile may include information about the user. FIG. 3 is a diagram pertaining to the setting-up of a user profile.
According to an exemplary implementation, a user profile-based assistance application residing on user device 125 - 1 may include a set-up procedure in which a user may create his/her user profile and set up user preferences. According to an exemplary embodiment, user device 125 and assistance device 110 may provide the means for a user to create his/her user profile and set up user preferences, as illustrated in FIG. 3 .
FIG. 4 is a diagram illustrating an exemplary user profile 400 stored by user profile storage 115 . As illustrated, user profile 400 may include a name field 405 , an image field 410 , an address field 415 , a time lived or worked field 420 , a profession field 425 , a time driving field 430 , an assistance category field 435 , a recordings field 440 , a types of service field 445 , an age field 450 , a user rating field 455 , and a user preferences field.
According to other embodiments, user profile 400 may additional, different, or fewer types of information. For example, user profile 400 may include an additional field that indicates level of education. As an example, an educational field may indicate whether a user completed college. Alternatively, the educational field may indicate the number of years of college (e.g., 2 years, 4 years, 6 years, etc.), degree level (e.g., associate, bachelor, master, doctorate, etc.), and/or type of degree(s) (e.g., MBA, J.D., B.S., etc.).
Name field 405 may store the user's name, such as first name or first name and last name. Image field 410 may store a picture of the user. Address field 415 may store the user's home and/or work address, such as city, state, and zip code. Time lived or worked field 420 may store the length of time (e.g., the number of years, months, etc.) the user has lived or worked at the address(es). Profession field 425 may store the user's profession, such as, doctor, attorney, teacher, etc. Time driving 430 may store the length of time (e.g., the number of years, months, etc.) the user has driven at the address(es). Assistance category field 435 may store one or more categories (e.g., monetary, shopping, restaurants, etc.) and/or sub-categories in which the user feels he/she can offer assistance. Recordings field 440 may store recorded audio conversations or video telephony communications, as requested by the user.
Types of service field 445 may store the types of service the user has with respect to the service provider. For example, the user may have, in addition to, the user profile-based assistance service, other types of service, such as mobile service, Internet service, and/or television service. This information may be used, among other things, to notify the user of assistance requests, etc. Age field 450 may store the user's age or age category (e.g., young, middle age, senior, etc.). User rating field 455 may store the user's rating based on other user's feedback. User preferences field 460 may store the user's preferences pertaining to the user profile-based assistance service. By way of example, as previously described, the user may set user availability (e.g., schedule), a user's preference of notification (e.g., via mobile service, etc.), and/or weighting preferences pertaining to selecting best user profiles. For example, the user may prefer other users of the same profession, age or age bracket, etc. According to an exemplary implementation, assistance device 110 may select the best user profiles to offer assistance for a user based on the user's preferences.
FIG. 5 is a diagram illustrating an exemplary GUI of a user's profile that may be viewed by other users. For example, assistance device 110 may provide a list of best user profiles from which a user may select when requesting assistance. As illustrated, the GUI may include a picture of the user 505 , a name of the user field 510 , a talk icon 515 , other user profile information 520 (e.g., address, years at location, profession, age, user rating), a previous icon 525 and a next icon 530 to permit the user to review other user profiles, and other user profiles 535 (e.g., names and pictures of other users) from which the user may select when requesting assistance.
As previously described, assistance device 110 may select one or more user profiles that will most likely satisfy the user's need of assistance. FIG. 6 is a diagram pertaining to the selection process of user profiles. According to an exemplary embodiment, assistance device 110 may use information included in a help request (e.g., help request 140 ) to identify candidate user profiles that may be best suited to assist a user. For example, the help request includes the destination of the user. The help request may also include information pertaining to the type of assistance.
Based on the destination information or the destination and type of assistance information, according to an exemplary implementation, assistance device 110 may generate a search query to search for user profiles stored by user profile storage 115 via user profile storage manager 120 . Assistance device 110 may receive, for example, a search result that includes a list of candidate user profiles. Assistance device 110 may then use a ranking algorithm to select the best possible candidate user profiles. According to some situations, when the destination location is remote, assistance device 110 may forego a scoring of and ranking of user profiles since there may be only one user profile.
According to an exemplary implementation, the ranking algorithm may score all or a portion of the user profiles included in the search result. For example, a score may be generated based on a weighting system. According to an exemplary implementation, the weighting system may be pre-configured in that a particular type of user profile information may be assigned a particular weighted value. According to other implementations, the weighting system may be dynamic and/or user-influenced based on user preferences and/or past user profile selections.
According to an exemplary embodiment, assistance device 110 may calculate a summation of each weight associated with each type of user profile information considered relevant. By way of example, the name of another user is not relevant nor his/her image. However, the time lived or worked in the location (e.g., field 420 of FIG. 4 ), the profession (e.g., field 425 ), and the user rating (e.g., field 455 ) may be particularly relevant. Additionally, some of the other types of user profile information may be impact the score of a user profile, such as age (e.g., field 450 ), user preferences (e.g., field 460 ), time driving (e.g., field 430 ), etc. According to an exemplary implementation, assistance device 110 may calculate a score S based on the following exemplary expression:
S = ∑ i = 1 n w i u i , ( 1 )
in which i indicates the number of types of user profile information (e.g., i . . . n=1 . . . 5), w indicates the weight attributed to the type of user profile information, and u indicates the type of user profile information. Assistance device 110 may then rank the user profiles based on their scores.
FIGS. 7A-7C are flow diagrams illustrating an exemplary process 700 for providing user profile-based assistance. According to an exemplary embodiment, some steps in process 700 are performed by assistance device 110 . For example, processing system 205 executes application 215 (e.g., a help-assistance application or program). Additionally, some steps in process 700 are performed by user device 125 . For example, processing system 205 executes a user profile-based assistance application or program.
In block 705 , a help request is received. For example, assistance device 110 receives a help request (e.g., help request 125 ) via communication interface 220 . The help request may take the form of a packet. The term “packet,” as used herein, is intended to be broadly interpreted to include a data transmission or a communication, the packaging of which may correspond to, for example, a packet, a cell, a frame, a datagram, some other type of container or unit of data, and/or a fragment thereof.
In block 710 , the destination included in the help request is identified. For example, assistance device 110 inspects the help request (e.g., field(s) of the packet) to identify a destination pertaining to the user's request for assistance. As previously described, according to other embodiments, the help request may include other information that may be useful in selecting best user profile candidates. For example, the help request may include an assistance category. The help request may also include information that identifies the user seeking assistance so that any user preferences are applied when selecting the best user profile candidates. For example, a user device identifier and/or a user identifier may be included in the help request. Alternatively, the help request may include user preference information. For example, the packet may include one or more user preference fields in which preferences, such as age, profession, etc., may be indicated.
In block 715 , a search query is generated. For example, assistance device 110 generates a search query. For example, the search query may take the form of a Structured Query Language (SQL) search query. According to other implementations, the search query may take the form of other known database languages (e.g., Object Query Language (OQL), Java Persistence Query Language, Language Integrated Query (LINQ), etc.). The search query includes the destination of the user requesting assistance. Additionally, the search query may include other relevant parameters, such as the assistance category and/or user preferences of the user requesting assistance (e.g., age, profession, time driving, etc.).
In block 720 , user profiles are searched based on the search query. For example, assistance device 110 searches user profile storage 115 via user profile storage manager 120 . According to an exemplary embodiment, the database stored by user profile storage 115 may include an index pertaining to destination locations. Additionally, according to an exemplary embodiment, the database may include indexes pertaining to age and destination, or other combinations of attributes applicable to a user profile or a user preference. According to an exemplary implementation, the search query is received by user profile storage manager 120 from assistance device 110 . The search is conducted and a search result is generated.
In block 725 , a search result is obtained. For example, user profile storage manager 120 provides a search query response, which includes a search result, to assistance device 110 .
In block 730 , scores for each user profile included in the search result are calculated. For example, assistance device 110 may use a ranking algorithm to score each user profile and select the best user profile(s). The best user profiles are selected based on the scores. Thus, user profiles having scores higher than other user profiles may be selected as candidate user profiles. As previously described, user profiles are scored on a weighting system, such as is expressed according to equation (1). According to an exemplary implementation, the weighted value assigned to a particular type of user profile information is a numerical value, which may be static or dynamic. For example, a user preference may increase the value of a weight assigned to a particular type of user profile information. Additionally, for example, past selections of user profiles by a user may be statistically evaluated to generate a weighted value to be assigned to a type of user profile information representative of the user's user profile selection preference. For example, user profiles previously selected by the user may be compared to identify common attributes and a user preference. Alternatively, a weighted value assigned to a type of user profile information may be static and pre-configured by a network administrator.
Referring to FIG. 7B , in block 735 , the user profiles are ranked based on the calculated scores. For example, assistance device 110 (e.g., the ranking algorithm) ranks the scored user profiles based on each score calculated for each user profile. According to an exemplary embodiment, user profiles are ranked based on a threshold score value. According to another embodiment, user profiles are ranked based on their respective scores. According to another exemplary embodiment, the number of user profiles selected and sent to the user (as described in block 735 ) may be limited by a particular number (e.g., no more than 20 user profiles, etc.). According to an exemplary implementation, assistance device 110 may select a candidate set of ranked user profiles and generate a user profile candidate list that includes the selected user profiles.
In block 740 , the availability of the ranked users is identified. According to an exemplary embodiment, assistance device 110 identifies which of the ranked users are available. The availability of the ranked user refers to either the ranked user's user preference (e.g., user availability (e.g., user schedule), preferred form of communication, etc.) or whether the ranked user is active in the service provider network 105 (e.g., whether the ranked user's user device 125 is turned on (e.g., vehicular communication system is turned on (e.g., the ranked user is driving), a mobile device is turned on, etc.) and/or the ranked user is currently using a service (e.g., user profiled-based assistance service, mobile service, television service, Internet service.)), or both (i.e., ranked user availability based on user preferences and network active).
Assistance device 110 may identify ranked users' preferences and match these preferences with the help request. For example, a date, day, time, etc., restrictions indicated in a ranked user's preference (e.g., user schedule) may be identified, by assistance device 110 , from the ranked user's profile and compared with the current date, day, time, etc. Additionally, or alternatively, assistance device 110 may identify whether a ranked user is network active. Depending on the services applied to the user profile-based communication assistance system, being able to identify the network activity of a ranked user may be more or less burdensome. For example, if assistance communication between users is limited to vehicular-based communication, assistance device 110 may be able to determine whether a ranked user is network active (e.g., the ranked user is also driving) because when a user profile-based assistance application or program is launched in the vehicular communication system, an initial service provider network 105 -to-user device 125 handshaking occurs. For example, in a 4G wireless network (e.g., a Long Term Evolution (LTE) network), the mobility management entity (MME) or the packet gateway (PGW) may identify whether the ranked user is network active. In a similar manner, if assistance communication between users also includes mobile service, the MME or the PGW may identify whether a ranked user is network active. According to an exemplary implementation, assistance device 110 may be informed of a user's network activity state (e.g., during connection set-up). For example, assistance device 110 may include a network interface to communicate with the MME, the PGW, etc. Similarly, other types of wireless networks (e.g., Code Division Multiple Access (CDMA), Global System for Mobile Communications (GSM), etc.) may include network devices (e.g., Mobile Switching Center (MSC), a Home Agent (HA), Packet Data Service Node (PDSN), etc.) that can identify whether users are network active. Additionally, according to an exemplary implementation, if a VoIP network is used (e.g., relative to a vehicular communication system or mobile service), a Session Initiation Protocol (SIP) server or a call agent device, may inform assistance device 110 that a ranked user is network active.
According to an exemplary embodiment, assistance communication between users may also include communication via television service. For example, a television distribution site (TDS) that services a user may identify when a set top box or other SPN television service interface device is being used. For example, a search server of the TDS site that services requests for content from a user via the set top box may identify a ranked user's network activity. The search server may inform assistance device 110 that a ranked user is network active.
According to an exemplary implementation, if a ranked user is not available, assistance device 110 selects another ranked user. Otherwise, if the ranked users are available, process 700 continues to block 745 .
In block 745 , the ranked user profiles are sent to user device 125 . For example, assistance device 110 may send the ranked user profiles, which have been selected, to user device 125 via communication interface 220 . According to an exemplary embodiment, the ranked user profiles include embedded contact information for each ranked user. The contact information may take the form of, for example, an Internet Protocol (IP) address and/or Media Access Control (MAC) address, a telephone number, an email address, and/or other contact address.
In block 750 , a selection of one of the ranked user profiles is received. For example, user device 125 receives a selection of one of the ranked user profiles and generates a connection request. The connection request includes the ranked user's contact information. User device 125 sends the connection request to the ranked user via service provider network 105 . The form of the communication may include, for example, a VoIP call or a video telephone call (e.g., when user devices 125 are vehicular communication systems), a wireless telephone call (e.g., when user devices 125 are mobile devices), a telephone call (e.g., a mobile device to a landline phone), an email message, a text message, etc.
In block 755 , the ranked user receives the connection request via user device 125 . According to this example, it may be assumed that the ranked user accepts the connection request and a communication session between the user seeking assistance and the ranked user is established. As previously described, according to an exemplary implementation, the user seeking assistance may send his/her location to the ranked user. In the event that the ranked user does not accept the connection request, the user may select another ranked user. Alternatively, the user may select multiple ranked users to initiate a communication session.
Referring to FIG. 7C , in block 760 , the user seeking assistance is prompted to rate the ranked user. For example, user device 125 may prompt the user to rate the ranked user when the communication has terminated. The user may rate the user vocally (e.g., via voice command) or via a GUI provided. The user may send the rating to assistance device 110 via user device 125 .
In block 765 , assistance device 110 may receive the user's rating and update the rating of the ranked user based on the user's rating. For example, if the ranked user's rating is 8 out of 10, and the user rates the ranked user as a 10, assistance device 110 recalculates the ranked user's rating. According to this example, the ranked user's rating increases in value. Assistance device 110 stores the updated ranking value in user profile storage 115 via user profile storage manager 120 . For example, assistance device 110 generates an update data request to user profile storage manager 120 .
Although FIGS. 7A-7C illustrate an exemplary process 700 for providing user profile-based assistance, according to other embodiments, process 700 may include additional operations, fewer operations, and/or different operations than those illustrated in FIGS. 7A-7C and described. For example, according to other embodiments, block 740 may be performed when the search results are obtained (e.g., at block 725 ), when scores are calculated (e.g., at block 730 ), or when user profiles are ranked (e.g., at block 735 ). According to yet another embodiment, block 740 may be omitted.
FIGS. 8A and 8B are flow diagrams illustrating another exemplary process for providing user profile-based assistance. According to an exemplary embodiment, process 800 is performed by user device 125 . For example, processing system 205 executes a user profile-based assistance application or program.
According to an exemplary embodiment, process 800 may be performed by a user device 125 , such as a vehicular communication system. For example, the vehicular communication system may include a computer having a display (e.g., a touch screen) and location-aware capability, as previously described. According to other embodiments, user device 125 may take the form of a mobile device, etc., as previously described.
The user profile-based assistance application or program may provide a user with various graphical user interfaces pertaining to the initial set up of a user profile and the use of the user profile-based assistance service. According to an exemplary implementation, the user-profile-based assistance application or program may include a client-based application or program. According to another implementation, the user profile-based assistance application or program may include a peer-to-peer application or program. According to an exemplary embodiment, the user profile-based assistance service may be directed to road assistance. Additionally, or alternatively, according to other embodiments, the user profile-based assistance service may pertain to other types of assistance, as previously described.
Referring to FIG. 8A , in block 805 , user device 125 receives a request for assistance. For example, the user may ask for help (e.g., vocally) or the user may input his/her request some other way (e.g., touching an icon displayed on a touch display, pressing a key, etc.).
In block 810 , user device 125 generates a help request and sends the help request to assistance device 120 . For example, user device 125 may generate the help request, which may take the form of a packet. User device 125 may prompt the user seeking assistance to provide the destination. Alternatively, user device 125 may identify the user's current location as the destination based on a user's confirmation. Depending on the circumstances, however, the user's current location may or may not correspond to the destination. For example, a user may request assistance before reaching his or her destination. User device 125 may also acquire other information from the user, such as the type of assistance needed (e.g., road assistance, monetary assistance, etc.). User device 125 may also prompt the user for other user preferences (e.g., age, profession, etc.). Alternatively, the user preferences of the user may be obtained by assistance device 110 .
The help request includes the user's destination. Additionally, the help request may include the type of assistance needed and/or user preferences. User device 125 sends the help request to assistance device 110 via service provider network 105 .
In block 815 , in response to the help request, user device 125 receives a ranked list of candidate user profiles. User device 125 displays the ranked list via a display. The user may choose to review the user profiles on the display. Alternatively, the user may request that the user-profile-based assistance application or program (e.g., including speech synthesis logic) vocalize (e.g., synthesize speech) the user profile information to the user. This may be helpful if the user is driving. The user may be able to set preferences to which fields in the user profile the user wishes to hear (e.g., just name and years lived and/or worked in location, or name, years lived and/or worked in location, and profession, etc.).
In block 820 , user device 125 receives a selection of one of the ranked user profiles, and in block 825 , generates an assistance request. The assistance request may take the form of a packet and includes the ranked user's contact information. The form of communication (e.g., a VoIP call, a video telephone call, etc.) may be selected by the user. Referring to FIG. 8B , in block 830 , user device 125 sends the assistance request to the ranked user via service provider network 105 .
In block 835 , as previously described, the ranked user has the option to accept or deny (e.g., ignore) the assistance request. For purposes of description, it may be assumed the ranked user accepts the assistance request and user device 125 of the ranked user generates an assistance response, which may take the form of a packet, and sends the assistance response to user device 125 of the user seeking assistance, via service provider network 105 . Thereafter, a communication session may be established.
In block 840 , user device 125 determines whether the communication session ends. For example, user device 125 determines when the communication between the user and the rank user ends based on communication interface 220 (e.g., when a disconnect message is sent or received). If it is determined that the communication has not ended (block 840 —NO), process 800 continues to wait (i.e., at block 840 ). If it is determined that the communication has ended (block 840 —YES), process 800 continues to block 845 .
In block 845 , the user seeking assistance is prompted to rate the ranked user. For example, user device 125 prompts the user to rate the ranked user when the communication is terminated. The user may rate the user vocally (e.g., via voice command) or via a GUI provided.
In block 850 , user device 125 receives the user's rating of the ranked user. User device 125 generates a rating message, which may take the form of a packet, and sends the rating message to assistance device 110 . The rating message includes the rating of the ranked user and an identifier of the ranked user.
Although FIGS. 8A and 8B illustrate an exemplary process 800 for providing user profile-based assistance, according to other embodiments, process 800 may include additional operations, fewer operations, and/or different operations than those illustrated in FIGS. 8A and 8B and described.
The foregoing description of embodiments provides illustration, but is not intended to be exhaustive or to limit the embodiments to the precise form disclosed. Accordingly, modifications to the embodiments described herein may be possible.
The terms “a,” “an,” and “the” are intended to be interpreted to include one or more items. Further, the phrase “based on” is intended to be interpreted as “based, at least in part, on,” unless explicitly stated otherwise. The term “and/or” is intended to be interpreted to include any and all combinations of one or more of the associated items. The phrase “tangible readable medium” is intended to be broadly interpreted to include the storage mediums described in relation to memory/storage 210 .
In addition, while series of blocks have been described with regard to the processes illustrated in FIGS. 7A-7C and FIGS. 8A and 8B , the order of the blocks may be modified according to other embodiments. Further, non-dependent blocks may be performed in parallel. Additionally, other processes described in this description may be modified and/or non-dependent operations may be performed in parallel.
An embodiment described herein may be implemented in many different forms of hardware and, software and/or firmware. For example, a process or a function may be implemented as “logic” or as a “component.” The logic or the component may include hardware (e.g., processing system 205 , etc.), a combination of hardware and software (e.g., application 215 ), a combination of hardware and firmware, or a combination of hardware, firmware, and software. An embodiment has been described without reference to the specific software code since the software can be designed to implement the embodiment based on the description herein.
In the preceding specification, various embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the broader scope of the invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded as illustrative rather than restrictive.
In the specification and illustrated by the drawings, reference is made to “an exemplary embodiment,” “an embodiment,” “embodiments,” etc., which may include a particular feature, structure or characteristic in connection with an embodiment(s). However, the use of the phrase or term “an embodiment,” “embodiments,” etc., in various places in the specification does not necessarily refer to all embodiments described, nor does it necessarily refer to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive of other embodiment(s). The same applies to the term “implementation,” “implementations,” etc.
No element, act, or instruction described in the present application should be construed as critical or essential to the embodiments described herein unless explicitly described as such. | A method including providing a user profile-based assistance service; receiving an assistance request from a subscriber, wherein the assistance request includes geographic information pertaining to a destination of the subscriber; searching a user profiles repository storing user profiles of other subscribers, wherein each user profile includes information indicating a geographic location in which the other subscriber has at least one of lived or worked; selecting candidate user profiles to offer assistance to the subscriber seeking assistance based on a matching between the geographic information pertaining to the destination and a geographic location in which each of the one or more other subscribers at least one of currently lives or works; sending the one or more candidate user profiles to the subscriber; receiving a selection of one of the one or more candidate user profiles; and establishing a communication session between the subscribe and the other selected subscriber. | 7 |
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
The invention relates to a railway level crossing, i.e. a crossing where road and rail are at the same level. This is also known as a grade crossing.
2. DESCRIPTION OF THE PRIOR ART
According to a press report, a new method has been adopted, initially in Recklinghausen, by the German Federal Railway in concert with Chemische Werke Huls AG and Gummiwerk Kraiburg, for the completion of much frequented railway level crossings, by replacing the hitherto usual road surface of asphalt, concrete plates or pavement by pre-shaped plates of a thickness of 193 mm and made of synthetic ethylene-propylene rubber. This material ("Allwetterkautschuk Buna AP") is highly resistant to ozone, ultraviolet light and other atmospheric effects. At raised temperatures it also displays good resistance to ageing, that is to say has no tendency to become brittle or to formation of cracks. The danger of road vehicles skidding in wet weather is prevented by the special profiling of the surface. The plates are provided with accurately profiled recesses for the sides of the rails and for fastening them to the rails, so that a fixed connection is assured. In addition to the technical advantages of considerably reducing assembly time and better resistance to road traffic, this new development is distinguished by a substantial reduction in the noise level of the road traffic crossing the rails.
Another known level crossing design, described in the leaflet "Rubber level crossings" of Trelleborgs Gummifabriks AB, is also based on a special rubber plate lying on a bed of joined-together wooden longitudinal beams, and completely covering this bed. The edges of the plates lying between the rails are provided with deep pre-shaped channels for the wheel flanges of a train. The lip of the channel directed upwards under the rail head is pressed against the underside of the rail head, so that the rubber plate is kept in its place on the wooden bed without the use of nails, bolts or adhesives. At the same time this results in effective sealing against dirt which might penetrate into the ballast bed. One of the advantages mentioned for such a level crossing is easier cleaning. On level crossings in industrial areas the channel need only be cleaned once in a while. Because of the elasticity of the rubber, removal of ice is also no longer a problem. Clamps screwed onto the ends of the bed of beams prevent the plates from shifting in the longitudinal direction.
U.S.A. Pat. No. 3,465,963 shows a level crossing in which the gap between a reinforced rubber plate and the rail is filled by an elastomeric strip. This strip has cavities in its underside enabling it to be resiliently deformed by the flange of a passing wheel.
U.S.A. Pat. No. 3,469,783 shows a level crossing wherein gaps between a concrete bed and the rails are filled by a cushioning member having internal cavities to allow it to be resiliently deformed by a passing flange.
SUMMARY OF THE INVENTION
An object of this invention is to provide an improved railway level crossing of the type having rubber plates forming at least part of the road surface between the rails.
Another object is to provide a railway level crossing in which it is not possible for a shoe heel or bicycle tire to get caught in a groove beside the rail.
Yet another object is to provide a railway level crossing which is not affected by dirt and refuse collecting in a groove and is resistant to adverse weather conditions.
The present invention is based on the realization that a pre-shaped channel to accomodate the wheel flanges of a train in the rubber plate is neither necessary or desirable in view of the risk, with the known design, of a shoe heel or a bicycle tire getting caught in said channel.
Therefore, the construction according to the invention is characterized in that an unyielding bed is provided between the rails and, at least adjacent each of the rails, the said road surface between the rails is provided by at least one flexible plate. The flexible plate is supported by said unyielding bed and has an edge portion extending to closely adjacent the rail. Thus even if there is any gap between the rail and the flexible plate, the gap has a width less than the amount by which a wheel flange projects laterally of the rail when a wheel passes along the rail.
Said edge portion of the flexible sheet is not directly supported by said unyielding bed whereby said edge portion can bend downwardly when engaged by a flange of a flanged wheel passing along the rail. There is further provided resilient means supporting said edge portion of the flexible plate and adapted resiliently to restore said edge portion to its normal position when the flanged wheel has passed. This closed construction adjacent the rail means that street refuse is blown across the level crossing and cannot accumulate in a groove.
Preferably said resilient means comprises, at least one gas-filled sealed tube of flexible material extending beneath the said edge portion of the flexible plate parallel to the rail and supported by a base. Such a tube may be a single unit extending across the full width of the road, but it can also be sub-divided into separate sections forming a plurality of tubes arranged end-to-end.
This resilient means may, in an alternative arrangement, consist of plate springs incorporated in the edge portion of the plate.
Preferably in order to promote easy bending of the plate, the flexible plate rests upon a portion of said unyielding bed at a region spaced from the rail the said portion of the unyielding bed having at its side towards the rail a top surface which is downwardly rounded to accommodate said flexing of the flexible plate.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the invention will now be described by way of non-limitative example with reference to the accompanying drawings, in which:
FIG. 1 shows in cross-section a single-track level crossing construction embodying the invention;
FIG. 2 shows a detail from FIG. 1 on an enlarged scale; and
FIG. 3 shows the same detail as FIG. 2 for another position of the wheel on the rail.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a single-track level crossing, in which rails 1 and 2 are fastened to crossing ties 7 in the usual way by fastening means 3 (hammer head bolts, vice clamps), backing plates 5 and collar bolts 6. However, the invention is applicable to other constructions of the track. Under the railway track the usual ballast bed 8 is provided.
The road 9, which crosses the railway on the same level, is in the illustrated example provided with a road foundation 10, upon which an asphalt binder 11 as well as a surface layer 12 have been provided. At the outsides of the rails 1 and 2, the gaps next to the ties 7 and the rail feet are filled with ballast gravel 13.
Wooden packing pieces 14 are provided between the rails 1 and 2 on the ties 7, upon which a bed 15 made up of joined-together wooden longitudinal beams rests to form an unyielding bed or flooring. Upon the lateral edge beams 15', 15" of this bed 15, rubber plates 16', 16" lie with their outside edges between and against rails 1 and 2. The use of two strips 16' and 16" particularly if the level crossing is situated on a curve of the railway track--can offer the advantages on the one hand of accurate measurements and on the other hand that these strips can be more easily pressed against the rails. (To give an example, a strip can measure 40 cm in width and 25 mm in thickness; the crevice between the edge of the strip and the side of the rail is about 1 mm wide and the distance between the top of the tie 7 and the top surface of the rubber plates amounts in this example to 19 cm). Between the strips 16' and 16" the bed 15 of the longitudinal beams thus at the same time forms part of the road surface between the rails 1 and 2. At their inside edges, the strips 16' and 16" are fastened to the underlying beams 15' and 15" respectively, preferably by means of a metal corner fillet (not shown) and wood screws countersunk into it.
The edge beams 15' and 15" at their sides towards the rails 1 and 2 respectively have their top surfaces rounded downwardly to accommodate the flexing of the plate described below.
Beneath the tongue or edge portion of each plate 16' and 16" overhanging the gaps between the beams 15', 15" and the rails 1,2 there is provided a closed rubber hose 17' and 17" filled with gas under pressure. These hoses 17', 17" rest on bases 18', 18" of for instance cold asphalt and give resilient support to the respective edge portions of the plates 16',16". As is apparent from the Figures, each hose 17', 17" has a circular cross section in its unloaded state. The hoses 17', 17" are attached to the bottoms of the respective plates 16',16", preferably with adhesive and have for example a diameter of 95 mm and a wall thickness of 8 mm. FIGS. 2 and 3 also show that the hose 17' rests in a recess 19 of the base 18', in order to prevent it from sliding away towards the rail. The hose may either extend across the full width of the level crossing or be sub-divided into separate sections. Subdivision may in particular be employed if the railway has a curve in that particular place.
FIGS. 2 and 3 show by broken line the degree of bending of the rubber plate 16' by the flange 21 of a wheel 20 of a passing railway vehicle. In FIG. 2 the flange 21 runs practically against the rail head, and in FIG. 3 is further from the rail head. In either case the deformation of the plate 16' and the hose 17' (drawn as a broken line) is only local and the pressure in the hose 17' ensures that the plate 16' resumes its flat position immediately after the wheel 20 has passed. Since the diameter of the hose 17' is large in proportion to the distance by which the wheel flange projects downwards from the rail head, there is no risk of the hose being pinched off by the passing flange.
The railway level crossing according to the invention therefore lacks the usual groove which enables the wheel flange to pass. Because of the smooth sealing of the groove according to the invention, the danger of shoe heels, tires of bicycles or mopeds or street refuse (sand, leaves etc) entering the groove--which danger will particularly be in evidence if the road and the railway cross each other at an oblique angle (for example of 45°)--can be completely eliminated. Thus a bicycle or moped wheel does not press down the rubber support plate to any appreciable extent, while is stands to reason that the wheel flanges of a train indeed do so.
Instead of a rubber hose the resilient support means for the plates may consist of plate springs (not shown) incorporated in the tongues or edge portions of the plates.
Advantages obtainable with the present invention are:
1. that the rail construction may continue unchanged in the crossing and on either side thereof;
2. the road surface is flat right up to the rail head, so hindering dirt from entering a groove (dirt and dust might in the long run cause damage to the crossing);
3. the rubber plates may be detachable on one side, so that dirt can be removed from time to time;
4. the rubber hose can be installed with the right internal pressure for good support for road traffic;
5. it is hardy to winter weather conditions (frost, snow, hail);
6. any unsymmetry of the position of the wheel flanges with respect to the rails does not affect its functioning. | A railway level crossing (grade crossing) is described in which the road surface between the rails is, at least adjacent the rails, provided by flexible plates, e.g. rubber plates. The plates extend right to the rails and under their edge portions adjacent the rails are resilient support means which allow the plate to flex downwardly when engaged by the flange of a wheel passing on the rail. The resilient support may be a gas-filled tube extending parallel to the rail. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/279,935 filed Oct. 28, 2009, the contents of which are incorporated herein by reference thereto.
FIELD OF THE INVENTION
[0002] The present invention relates to systems and methods of powering lights of passenger vehicles, especially all-day lights on, hybrid and electrical vehicles, trucks, motorcycles, trains, ships, even boats, all of which are simply called vehicles and more particularly to systems and methods that employ a thermal and light energy dispersed by a vehicle regular illuminating light bulb and solar energy to power the emergency and parking lights of the vehicle that further in the text are called safety lights when the electrical system of the vehicle is turned off and the vehicle regular electrical sources are not available.
BACKGROUND OF THE INVENTION
[0003] There are different kinds of vehicle illuminating and safety lights. A vehicle headlight assembly, for example, may be equipped with a light source, at least one reflecting surface, a projection lens, and a shutter located in the vicinity of a focus of the projection lens. Light rays reflected by the reflecting surface and directly coming from the light source provide a focused image of light. The projection lens projects the focused image of light into a forward direction and illuminates a predetermined area on a road. The shutter cuts off an unnecessary portion of light for the formation of light distribution pattern of the vehicle light. The unnecessary portion of light is typically a portion which generally illuminates in the direction of the vehicle, which can be a glare light to a driver of a car driving in an on-coming lane.
[0004] The light source of the vehicle headlight and all other vehicle warning, illuminating, safety, tail, brake, stop, etc. lights may consist of an incandescent bulb, a halogen source, a light emitting diode (LED) based source, etc. All these types of light sources are powered by the vehicle electrical system. The lights are typically dark when an engine is shut down. From a safety point of view, it is important to keep the vehicle light turned on as an emergency or safety light when a vehicle is parked, especially during the dark part of day. But the operator of a vehicle can't leave them turned on for a long period of time when the engine is shut down because a battery will become discharged.
[0005] There is a need for a method and system to collect and save multi-energy to power the emergency and parking lights when the regular vehicle electrical sources are not available.
SUMMARY OF THE INVENTION
[0006] A system and method to collect and store thermal (infrared) and light (visible) energy dispersed by a vehicle regular illuminating light and, together with also collected and stored solar energy, to employ this combined stored multi-energy to power the safety lights of this vehicle and to use the rest of this stored multi-energy to power an electrical system of the vehicle or any its units are presented.
[0007] The present invention provides a method and system to collect and store thermal and light energy dispersed by a regular vehicle light source and use this stored multi-energy to power the safety lights when the electrical system of said vehicle is turned off and its regular electrical sources are not available.
[0008] In one embodiment, a vehicle multi-energy illuminating system is disclosed. The system having at least one multi-energy source module configured to collect waste energy from a vehicle headlamp, the at least one a multi-energy source module having at least one photovoltaic device configured to collect infrared energy and at least one photovoltaic device configured to collect visible light energy from the vehicle headlamp: at least one solar energy source module configured to collect visible light energy not generated from the vehicle headlamp bulb; a rechargeable battery coupled to the least one multi-energy source module and the at least one solar energy source module, the rechargeable battery being configured to collect and store the waste energy from the headlamp bulb and the visible light energy not generated from the vehicle headlamp bulb; a safety light; a light sensor; and a microcontroller coupled to the rechargeable battery, the safety light and the light sensor, wherein the microcontroller illuminates the safety light by coupling the safety light to the rechargeable battery when the light sensor provides a signal to the microcontroller indicating that detected light is below a predetermined value.
[0009] In another embodiment, a method of illuminating a safety light of a vehicle is provided. The method having the steps of: collecting waste energy from a vehicle headlamp bulb with at least one multi-energy source module, the at least one a multi-energy source module having at least one photovoltaic device configured to collect infrared energy from the vehicle headlamp bulb and at least one photovoltaic device configured to collect visible light energy from the vehicle headlamp bulb: collecting visible light energy not generated from the vehicle headlamp bulb with at least one solar energy source module; storing the collected solar energy and the collected waste energy in a rechargeable battery coupled to the least one multi-energy source module and the at least one solar energy source module, the rechargeable battery being electrically coupled to the at least one solar energy module and the at least one multi-energy source module; and illuminating a safety light by coupling the rechargeable battery to the safety light when a light sensor provides a signal indicative of light below a predetermined value, wherein the rechargeable battery, the safety light, the light sensor, the at least one solar energy module and the at least one multi-energy source module are coupled to a microcontroller, wherein the microcontroller illuminates the safety light by coupling the safety light to the rechargeable battery when the light sensor provides the signal to the microcontroller indicating that detected light is below the predetermined value.
BRIEF DESCRIPTION OF THE DRAWING
[0010] The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:
[0011] FIG. 1 is a schematic diagram of the Multi-Energy vehicle Light system;
[0012] FIG. 2 is a simplified Multi-Energy vehicle Light system headlight assembly.
DETAILED DESCRIPTION
[0013] In accordance with an exemplary embodiment of the present invention a method and system are provided that collect and employ the two different types of energy (Multi-Energy)—infrared and visible light energy—to keep a vehicle safety lights turned on when the vehicle is parked, especially in darkness, and the electrical system of the vehicle is turned off, powered by energy that was collected and saved by a multi-energy source (MES) module, and the method comprises Multi-Energy Illuminating Technology (MUEL-T). As used herein and in one non-limiting exemplary embodiment Multi-Energy Illuminating Technology is the combination of a multi-energy source module having at least one photovoltaic device configured to collect infrared energy from the vehicle headlamp bulb or other vehicle surface and at least one photovoltaic device configured to collect visible light energy from the vehicle headlamp bulb or other vehicle surface and at least one solar energy source module.
[0014] Another exemplary embodiment of the present invention allows a method to improve safety of any vehicle by powering its safety lights at night or in darkness independent of weather conditions when the vehicle is in an emergency situation or parked, and an electrical system of the vehicle is not available at that time.
[0015] Another exemplary embodiment allows a system for powering vehicle's safety lights at night or in darkness independent of weather conditions when the vehicle is in an emergency situation or parked, and an electrical system of the vehicle is not then available.
[0016] Yet another exemplary embodiment of the present invention is that a safety light of a Multi-Energy vehicle Light (MUEL) system is powered by the two types of energy to keep the vehicle safety lights turned on at the discretion of an operator when the vehicle is parked and an electrical system of the vehicle is not available.
[0017] In addition, and as yet another exemplary embodiment of the present invention, the multi-energy MUEL system accomplished by the MUEL-T technology includes the two energy sources. The first energy source of the MUEL system and method is the multi-energy source MES module that collects and transforms to electricity by photovoltaic devices and stores by rechargeable battery a thermal and light energy dispersed by a vehicle regular illuminating light bulb such as a headlight when the light is turned on.
[0018] The MES module collects the waste light and infrared energy of a vehicle regular illuminating light bulb at any time when the MUEL light bulb, which is next to the MES module, is turned on at the discretion of the operator of the vehicle. In exemplary embodiment, one set of the photovoltaic devices of the MES module accomplished by the MUEL-T technology is designated to convert waste light energy of a vehicle regular illuminating light bulb to electrical energy and has light wavelength. This set of the photovoltaic devices may be fixed on the side of the MES module that is closer to the MUEL light bulb.
[0019] The second set of the photovoltaic devices of the MES module accomplished by the MUEL-T technology is designated to convert waste infrared energy of a vehicle regular illuminating light bulb to electrical energy and has an infrared wavelength. This set of the photovoltaic devices may be fixed on the other side of the MES module.
[0020] As an alternative embodiment another than photovoltaic suitable type of energy converters may be employed to transform to electricity the waste heating energy dispersed by the MUEL light bulb. For example, flat nanoantenna (nantenna) electromagnetic collectors (NECs) may be used for producing electricity from thermal energy. NEC devices target midinfrared wavelengths where conventional photovoltaic solar cells are inefficient. Nantennas with embedded rectifiers into the antenna structures can collect as well as convert into electricity waste heating energy dispersed by the MUEL vehicle regular illuminating light bulb.
[0021] Additionally, the internal lateral surfaces and bottom surface of a MUEL light assembly around the bulb may be covered by the flat nanoantenna (nantenna) electromagnetic collectors with embedded rectifiers, which in this case will work as collectors of thermal energy, coolers of inside temperature, and reflectors of the bulb of the MUEL light assembly.
[0022] The second energy source of the MUEL system and method is a Solar Energy Source (SES) module that consists of photovoltaic devices that have light wavelength. The goal of the SES module is to provide MUEL system with solar energy, and it may be located at any appropriate part of the MUEL system that provides access to solar energy.
[0023] Another exemplary embodiment of the present invention is that a SES module and a MES module accomplished by the MUEL-T technology may be manufactured as a combined “sandwich” (MESES) module, in which the MES module is located next to a MUEL light bulb, and the SES module on another side of the MESES module has access to the sunlight.
[0024] Exemplary embodiments of the present invention allow a MUEL light accomplished by the MUEL-T technology to consist at least one MES module or at least one MES module and at least one SES module or at least one MESES module or at least one MESES module and at least one SES module.
[0025] A schematic diagram of the preferred embodiment of the MUEL system 10 accomplished by the MUEL-T technology is shown in FIG. 1 . A vehicle multi-energy MUEL system 10 consists of the MES module 30 that is a part of the MESES “sandwich” energy collector 11 , which collects both solar energy and waste visible (light) and heating (infrared) energy of the light bulb 13 , the SES modules 31 a , 31 b , 31 c , where the first of which is a part of the MESES “sandwich” 11 , and all of these SES modules collect solar energy and are connected to the rechargeable battery 33 through the diodes 37 , which prevent the battery's current from flowing back through the photovoltaic module, the vehicle safety light 32 that may be a light emitting diode (LED) based or other lighting source, the light sensors 34 , 34 b , 34 c , the microcontroller unit 35 , the charger 36 , the switches 38 , 39 , 44 , 49 , the measurement resistors 40 , 42 , and operational amplifiers 41 , 43 . At night the photovoltaic modules 31 a , 31 b , and 31 c stop to produce energy from solar light. The light sensor 34 b turns on vehicle safety light 32 through switch 38 in darkness if vehicle headlight bulb 13 of the light 12 is not turned on and switch 39 , controlled by the light sensor 34 is not turned off. When the rechargeable battery 33 is charged, vehicle safety light 32 will shine at night or in darkness and will provide safe parking of a vehicle or safe location of the vehicle on a road in case of an emergency stop.
[0026] In addition, and as yet another exemplary embodiment of the present invention, the MUEL system accomplished by the MUEL-T technology is configured with a microcontroller unit (MCU) 35 that monitors energy collected by MES 30 and SES 31 modules by use of a voltage drop across resistor 40 . This voltage is amplified by an operational amplifier 41 and is processed by the MCU 35 on its ADC1 (Analog-to-Digital Converter) terminal. The amount of energy delivered to the rechargeable battery 33 is memorized by MCU 35 . The MCU 35 monitors the energy lost by a rechargeable battery 33 while serving the safety light by analyzing a voltage drop across resistor 42 . This voltage is amplified by operational amplifier 43 and is processed by the MCU 35 on its ADC2 terminal. When light sensor 34 b of the SES module turns off the safety light in a sunny morning, the MCU calculates the residual of the collected energy by the MUEL. If enough energy is left, MCU through its terminal I/O 1 switches the output terminal of the rechargeable battery through switch 44 from the position of providing service to the safety light 32 line to the position of powering any electrical energy consumer line of the vehicle electrical system.
[0027] Yet another exemplary embodiment of the present invention is that the multi-energy MES module 30 of the MUEL system accomplished by the MUEL-T technology is fixed next to the MUEL light bulb 13 .
[0028] Another exemplary embodiment of the present invention is that the rechargeable battery may be fixed at the light assembly accomplished by the MUEL-T technology in the same way as a light bulb. If more than one rechargeable battery is used, they may be arranged in a parallel or a series combination.
[0029] Another exemplary embodiment of the present invention is that the rechargeable battery may be located in a special compartment in the hood of a vehicle and connected to the MUEL by the same connector to which a bulb is connected. Part of the schematic may be located in the same compartment as the rechargeable battery.
[0030] Another exemplary embodiment of the present invention is that there are openings in the MUEL assembly accomplished by the MUEL-T technology above the SES modules to get sunlight by the photovoltaic devices 31 a , 31 b , and 31 c . The openings are closed by glass or other material that protects solar modules from mechanical damage and are transparent to solar energy.
[0031] Another exemplary embodiment of the present invention allows a retractable cover above the SES module of the MUEL.
[0032] Another exemplary embodiment of the present invention is that the vehicle MUEL system accomplished by the MUEL-T technology may store energy that it collects through MES module both light and infrared energy at any time when the light bulb of the MUEL is turned on and solar energy through SES modules on sunny days. MUEL system may store energy that it collects through both MES and SES solar energy on sunny days when the light bulb of the MUEL is turned off.
[0033] Another exemplary embodiment of the present invention is that location of the SES module may be anywhere in the MUEL system. If the size of the vehicle light assembly allows, there may be more than one SES module in the MUEL light accomplished by the MUEL-T technology.
[0034] FIG. 2 shows a simplified MUEL system 10 headlight assembly accomplished by the MUEL-T technology. A MUEL assembly consists of a headlight bulb 13 , a sandwich MESES 49 , and safety light 32 . The sandwich MESES 49 in turn consists of a MES module 30 and SES module 31 a . The MES module 30 located next to the light bulb 13 and includes a light sensor 34 . The SES module 31 a located above the MES module 30 and includes a light sensor 34 a . The MUEL assembly also consists of another SES module 31 b , which includes a light sensor 34 b . FIG. 2 also shows a direction of a headlight beam 47 . The two internal lateral surfaces and bottom surface 48 of the MUEL assembly are employed as reflectors. The MES module 30 collects both waste light and waste infrared energy dispersed by the light bulb 13 of the MUEL system at any time when it is turned on. The SES module 31 a and SES module 31 b both collect solar energy on sunny days.
[0035] Another exemplary embodiment of the present invention is that depending on an internal structure of the MUEL light assembly the location of modules accomplished by the MUEL-T technology is chosen in a way when they collect the most of infrared and visible energy. Each employed MES and SES module may contain at least one light sensor.
[0036] Yet another exemplary embodiment of the present invention is that each MES module light of the MUEL system accomplished by the MUEL-T technology is located in the area of the vehicle illuminating light bulb in which it consumes most of the waste by the bulb thermal and light energy and does not disturb the characteristics of the light, and the ambient temperature of the MES is in the allowed range.
[0037] In addition, and as yet another exemplary embodiment of the present invention, the two or more regular vehicle lights (for example, headlights, parking lights, side-marker lights, etc.) may be combined in one assembly to create a Combined MUEL (COMUEL) light system accomplished by the MUEL-T technology.
[0038] Yet another exemplary embodiment of the present invention is that each SES module of the MUEL system accomplished by the MUEL-T technology is located in the area of the light assembly where it consumes most of the solar energy and does not disturb the characteristics of the light, and the ambient temperature of the SES is in the allowed range.
[0039] Table 1 shows the conditions of the rechargeable battery and safety light of a MUEL system accomplished by the MUEL-T technology depending on weather and time of day.
[0040] Another exemplary embodiment of the present invention is that the charger 36 is used to prevent the rechargeable battery from overcharging by employing the signal I/O 3 of the MCU 35 . The charger 36 may also be employed when there is more than one SES module. The charger and rechargeable battery may be fixed in the MUEL assembly or outside of it.
[0000]
TABLE 1
1
Position of an illuminating light switch
On
Off
2
Weather, time of day
Sunny
Darkness
Sunny
Darkness
3
MES
4
Energy to charge
+
+
+/−
−
5
Light sensor output
Off
Off
Off
On
6
SES
7
Energy to charge
+
−
+
−
8
Light sensor output
Off
On
Off
On
9
MUEL
10
Energy to charge
+
+
+
−
11
Battery
12
Charging
+
+
+
−
13
Discharging
−
−
−
+
14
Safety light
Off
Off
Off
On
[0041] Another exemplary embodiment of the present invention is that the charger 36 is used to prevent the rechargeable battery from overcharging by employing the signal I/O 3 of the MCU 35 . The charger 36 may also be employed when there is more than one SES module. The charger and rechargeable battery may be fixed in the MUEL assembly or outside of it.
[0042] Yet another exemplary embodiment of the present invention in which a regular rotating switch may be used to turn off a safety light of a MUEL system accomplished by the MUEL-T technology or an automatic turn of the safety light may be adjusted by the operator of the vehicle through switch 49 and I/O 2 terminal of the MCU 35 .
[0043] In addition, and as yet another exemplary embodiment of the present invention, all features of the MUEL-T technology as it is described for a vehicle headlight above related to all types of possible lights of the passenger vehicles, especially all-day lights on, hybrid and electrical vehicles, trucks, motorcycles, trains, ships, even boats in which the lights are realized as the MUEL-type safety lights.
[0044] In still yet another alternative exemplary embodiment the method and system accomplished by the MUEL-T technology may employ a vehicle SLI (starting, lightning, and ignition) battery through a charger 36 as a main storage of the multi-energy collected by the MUEL system. In this case the vehicle SLI battery powers the safety light if the MUEL system saves energy enough.
[0045] In addition, and as yet another exemplary embodiment of the present invention, a collector of infrared energy may be fixed on a hot surface of a vehicle engine and may collect its thermal energy that may be combined with the energy saved by of a MUEL system accomplished by the MUEL-T technology.
[0046] The multi-energy MUEL system accomplished by the MUEL-T technology for powering emergency and parking lights is more reliable than any other solar emergency and parking system because MUEL system provides power to the emergency and parking lights independently of the weather.
[0047] In various embodiments a vehicle multi-energy illuminating (MUEL) system that provides energy sources is disclosed. In one embodiment the system collects and stores thermal and light energy dispersed by a vehicle regular illuminating light bulb and also provide energy sources that collect solar energy, and the MUEL system uses combined collected and stored multi-energy to power safety lights of providing energy sources, which collect and store a thermal and light energy dispersed by a vehicle regular illuminating light bulb and also providing energy sources that collect solar energy, and the MUEL system uses combined collected and stored multi-energy to power safety lights of the vehicle when an electrical system of the vehicle is turned off and its regular electrical sources are not available, and employs the rest of the stored energy to power the electrical system of the vehicle or any its units.
[0048] In one non-limiting embodiment, the energy sources are: at least one multi-energy source (MES) module that is next to the vehicle regular illuminating light bulb and employs a photovoltaic devices to collect: a. Visible (light) waste energy of the vehicle regular illuminating light bulb; b. Heating (infrared) waste energy of the vehicle regular illuminating light bulb; and at least one photovoltaic Solar Energy Source (SES) module that collects solar energy.
[0049] In another embodiment, the vehicle multi-energy illuminating MUEL system consists of at least one multi-energy MES module, at least one Solar Energy Source SES module, and all of the modules are connected to a rechargeable battery through the diodes, which prevent the battery's current from flowing back through the modules, a vehicle safety light, a rechargeable battery, a darkness or light sensor(s), a microcontroller unit MCU, a charger, the switches, the measurement resistors, the operational amplifiers, and multi-energy MES module in turn consists of at least one set of the photovoltaic devices that is designated to convert waste infrared energy of the illuminating light bulb to electrical energy and has an infrared wavelength, and the second set of the photovoltaic devices of the MES module is designated to convert waste light energy of the vehicle regular illuminating light bulb to electrical energy and has visible light wavelength.
[0050] In one implementation, the MCU monitors energy collected by MES and SES modules by use of a voltage drop across measurement resistor, and the voltage drop is connected to and amplified by an operational amplifier and after that it is connected to and processed by the MCU, which memorizes the amount of energy delivered to the rechargeable battery. In another implementation, the MCU monitors energy lost by the rechargeable battery, while serving the safety light, by use of a voltage drop across measurement resistor, and the voltage drop is connected to and amplified by an operational amplifier and further it is connected to and processed by the MCU, which monitors the amount of saved energy.
[0051] In an exemplary embodiment and in a sunny morning, when darkness or light sensor sends a signal to the MCU to turn off the safety light, the MCU calculates the residual of the collected energy by the MUEL system and, if enough energy is left, the MCU through its I/O terminal switches the output terminal of the rechargeable battery from a position of providing service to the safety light line to the position of powering any predetermined electrical energy consumer line of the vehicle electrical system.
[0052] During operation the photovoltaic devices of the SES module stop producing power from solar light at night and the darkness sensor at the discretion of a operator of the vehicle turns on the vehicle safety light through a switch in darkness if the vehicle regular headlight bulb is not turned on and switch, controlled by the darkness sensor is not turned off.
[0053] In yet another embodiment, the multi-energy MES module and the SES module are manufactured together as one “sandwich” MESES module, in which the MES module is fixed next to the vehicle regular headlight bulb and the SES module is fixed on another side of the MESES module and has access to the sunlight. Still further and in one embodiment, the system comprises a vehicle regular headlight bulb, a sandwich MESES, vehicle safety light, and the sandwich MESES in turn consists of the MES module and the SES module, and the MES module located next to the vehicle regular headlight bulb and includes a darkness sensor, and the SES module is located above the MES photovoltaic module and includes a darkness sensor, and the headlight assembly of the MUEL system also consists another SES module, which includes a darkness sensor, and the two internal lateral surfaces and bottom surface of a vehicle regular illuminating light around of the bulb of the MUEL system assembly are employed as reflectors.
[0054] In yet another implementation, two or more regular vehicle lights such as headlight, parking light, side-marker light, tail light, brake light, stop light, etc. are combined in one assembly to create a vehicle combined multi-energy illuminating system (COMUEL). Still further, the headlight assembly of the MUEL system includes a charger that prevents the rechargeable battery from overcharging by employing an I/O terminal of the MCU.
[0055] In another embodiment, the multi-energy MES module consists of infrared flat nanoantenna (nantenna) electromagnetic collectors (NECs) with embedded rectifiers into the antenna structures to convert waste infrared energy of the illuminating light bulb into electricity and have an infrared wavelength, and the internal lateral surfaces and bottom surface of a MUEL light assembly around of the bulb are covered by the infrared flat NECs with embedded rectifiers, which in this case will work as collectors of thermal energy, coolers of inside temperature, and reflectors of the MUEL light assembly.
[0056] Still further and in one mode of operation, a vehicle SLI (starting, lightning, and ignition) battery is connected to the charger as a main storage of the multi-energy collected by the MUEL system and the vehicle SLI battery powers the safety light through the MCU and a control circuit. In another embodiment, the infrared flat NECs with embedded rectifiers are fixed on a hot surface of a vehicle engine and collect thermal energy dispersed by the engine that is combined with other energy saved by the MUEL system to power emergency and safety vehicle lights.
[0057] As also disclosed herein, a multi-energy method of powering a vehicle safety lights by collecting and storing thermal (infrared) and light (visible) energy dispersed by a vehicle regular illuminating light bulb and also collecting and storing visible solar energy and employing this combined stored multi-energy to power safety lights of the vehicle when its regular electrical sources are not available is provided, wherein visible solar energy is collected by a visible solar energy (SES) photovoltaic module, and the both infrared and visible energy dispersed by the vehicle regular illuminating light bulb are collected simultaneously by a multi-energy (MES) module that consists of both an infrared and a visible light collectors accordingly, and the collectors have different wavelength, and the collectors and converters of visible and infrared energy into electrical energy are any type.
[0058] Here, the multi-energy module MES collects energy from the vehicle regular illuminating light bulb at any time when the light bulb, which is next to the MES module, is turned on at the discretion of the operator of the vehicle, and the solar energy SES module collects energy at any sunny day. In another mode of operation, the infrared part of the multi-energy MES module collects thermal energy dispersed by the vehicle regular illuminating light bulb, is accomplished by infrared flat nanoantenna electromagnetic collectors (NECs) with embedded rectifiers to convert infrared energy into electricity, and the multi-energy MES module is combined with the visible solar energy SES module as a “sandwich” MESES, in which the visible light photovoltaic devices of the multi-energy module MES are fixed next to the vehicle regular headlight bulb, and the SES photovoltaic module on the other side of the MESES has access to the sunlight, and the two internal lateral surfaces and bottom surface of the MUEL light are covered by the infrared flat NECs collectors with embedded rectifiers, which are employed as collectors of thermal energy, coolers of inside temperature, and reflectors of the bulb of the MUEL light assembly.
[0059] As discussed above and in one implementation, the multi-energy module MES is combined with the visible solar energy SES module as a “sandwich” MESES module, in which the visible light photovoltaic devices of the multi-energy module MES are fixed next to the vehicle regular headlight bulb, and the SES photovoltaic module on the other side of the MESES has access to the sunlight, and there are openings in the MUEL assembly accomplished by the MUEL-T technology above the SES module to get sunlight, and the openings are closed by glass or other material that protects MUEL from mechanical damages and are transparent to solar energy, and the “sandwich” MESES module may be manufactured, sold, and employed as a separate multi-energy converter and saver.
[0060] While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the described features. | A vehicle multi-energy illuminating system is disclosed. The system having at least one multi-energy source module configured to collect waste energy from a vehicle headlamp, the at least one a multi-energy source module having at least one photovoltaic device configured to collect infrared energy and at least one photovoltaic device configured to collect visible light energy from the vehicle headlamp: at least one solar energy source module configured to collect visible light energy not generated from the vehicle headlamp bulb; a rechargeable battery coupled to the least one multi-energy source module and the at least one solar energy source module, the rechargeable battery being configured to collect and store the waste energy from the headlamp bulb and the visible light energy not generated from the vehicle headlamp bulb; a safety light; a light sensor; and a microcontroller coupled to the rechargeable battery, the safety light and the light sensor, wherein the microcontroller illuminates the safety light by coupling the safety light to the rechargeable battery when the light sensor provides a signal to the microcontroller indicating that detected light is below a predetermined value. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/539,361, filed Jan. 27, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to frame construction, such as decks and docks, and, more particularly, to a fastener-free framing system by which plank members are secured to frame members through ribs which are engaged within receptor pockets.
[0004] 2. Description of Related Art
[0005] Exterior decks are considered to be the most popular addition to homes throughout the United States today. Decks are places where people can extend their living space beyond the walls of their home. Decks are built out of a variety of materials and are fabricated in a variety of designs.
[0006] Typically, decks and similar structures are constructed with horizontal planking materials and are fastened to an underlying structural frame. The most popular planking and structural framing material is pressure treated wood. Pressure treated wood contains harmful toxins; one of them is called Copper-Chromium Arsenic (CCA). It is designed to extend the life of the product in exterior elements and protect it from weather and insect infestation, such as termites. However, pressure treated wood planking tends to warp, rot, splinter and require periodic maintenance. These problems are inherent only in wood and are accelerated in exterior climates.
[0007] The structural frame for the majority of the decks built in the United States is constructed out of pressure treated wood due to the familiarity and availability of the product. However, other alternative planking materials are plastic/wood composite, synthetic, extruded plastics, extruded metals, cold-rolled metals, and extruded aluminum, etc.
[0008] Attaching the planking to the structural frame with fasteners, through the surface into the underlying structure, is the most commonly accepted method in the industry. There are other methods that conceal the fastening system from the underside using special clips, brackets and the like. However, this typically requires the same amount or additional fasteners to adequately connect planking to the supporting substructure.
[0009] Attaching the planking to the structural frame through the top planking surface yields unsightly blemishes to the decking surface. Typically, planking members require two fasteners to be installed through its surface into the underlying substructure (joists) to be adequately installed. More specifically, where a planking member crosses over the underlying substructure, two fasteners must be installed.
[0010] Attaching the planking to the structural frame through the bottom planking surface using specialty clips is a slow and tedious process requiring more skilled labor and fasteners to adequately install. There are often space requirements below the structure and above the ground to adequately install subsurface fastening systems.
[0011] If nailed, these fasteners can work themselves out of the substructure, just above the surface, and cause injury. Special screws can reduce the chances of nail popping but are typically more expensive since they must be non-corrosive to avoid weathering and often require specialty tools to fasten them. Fastening the planks to the substructure using screws is the most advantageous method, however, it requires some skill to properly place so that the fastening holes align somewhat consistently with the others.
[0012] As mentioned, wood structures have many disadvantages. They rot, warp, split, splinter, burn, require annual maintenance, burn, get eaten by termites, are only produced in limited pre-cut lengths, and are not recyclable just to name a few. In order to extend the life of wood structures, special preservatives, like Copper-Chromium Arsenic (CCA) are applied to them. However these chemicals have been found to be toxic and the growing environmental impact concerns have led the Environmental Protection Agency (EPA) to begin nationwide bans on these chemicals starting Jan. 1, 2004. There will be serious impacts on the industry like lack of product supply, increased costs and product capabilities.
[0013] It is obvious that an alternative framing system that eliminates fastening of the planking must be developed. If it is possible to produce an alternative underlying framing structure that does not require chemicals treatment to make them effective, then that must be developed as well. Currently, there are no solutions that integrate popular planking systems like composite and extruded decking materials with the underlying substructure without the use of special fasteners like screws, nails or clips, etc.
[0014] Therefore, an object of the present invention is to provide a plank member that has a special shape integrated on the underside of the plank, which is used to attach itself to the underlying structure without fasteners.
SUMMARY OF THE INVENTION
[0015] One embodiment of the subject invention is directed to a framing system comprising a plank member having a front, generally fiat, surface and an opposing back surface with at least one rib protruding therefrom or at least one receptor pocket extending therein. The framing system has a frame member of an underlying structure having at least one receptor pocket extending therein or at least one rib protruding therefrom, wherein the frame member rib or pocket is matable with the plank member pocket or rib. The at least one rib has a profile with a first side and a second side which diverge from one another as they extend away from the member to which they are attached and then converge. The maximum height of a rib occurs at the place of maximum divergence and the receptor pocket has a minimum width less than that of the maximum height of the rib such that the rib may be captured within the receptor pocket.
[0016] Another embodiment of the subject invention is directed to a plank member comprising a front, generally flat, surface and an opposing back surface with at least one rib protruding therefrom. The at least one rib has a profile with a first side and a second side which diverge from one another as they extend away from the member to which they are attached and then converge. The maximum height of a rib occurs at the place of maximum divergence such that the rib is adapted to be received within a receptor pocket having a minimum width less than that of the maximum height of the rib.
[0017] Yet another embodiment of the subject invention is directed to a frame member of an underlying structure, wherein the frame member comprises at least one receptor pocket extending therein, wherein the pocket is adapted to receive a rib. The receptor pocket has a minimum width less than that of the maximum height of the rib such that the rib may be captured within the receptor pocket.
[0018] Yet another embodiment of the subject invention is directed to a method of assembling a framing system having a plank member with a front, generally flat, surface and an opposing back surface with at least one rib protruding therefrom or at least one receptor pocket extending therein and having a frame member of an underlying structure with the other of at least one receptor pocket extending therein or at least one rib protruding therefrom, wherein the frame member rib or pocket is matable with the plank member pocket or rib. The method comprises the steps of:
a) aligning the at least one rib with the at least one receptor pocket; b) urging the at least one rib within the at least one receptor pocket until the rib snaps into the pocket; and c) wherein the at least one rib or the at least one receptor pocket is resilient.
[0022] Still another embodiment of the subject invention is directed to a method of making a frame member adapted to receive protruding ribs from a plank member comprising the steps of:
a) punching slots within a flat sheet; and b) bending the sheet into a structural member having a top surface and a bottom surface, wherein the slots extend within the top surface to provide a receptor pocket adapted to receive the protruding ribs from the plank member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a perspective view of a framing system in accordance with the subject invention;
[0026] FIG. 2 is an enlargement of the encircled portion found in FIG. 1 ;
[0027] FIG. 3 is a section view indicating the manner in which the plank member and frame member are engaged;
[0028] FIGS. 4A and 5A are section views similar to that of FIG. 3 , but illustrating different embodiments of the plank member;
[0029] FIGS. 4B and 5B are section views identical to FIGS. 4A and 4B , except the rib in each is in a compressed state;
[0030] FIGS. 6A and 6B are side views similar to that of FIG. 3 , but illustrating how the frame member may deflect to accommodate the rib;
[0031] FIG. 7 is a section view of a framing system with the receptor pockets on the plank member and the ribs on the frame member;
[0032] FIG. 8 is a section view of the plank member with a separate piece rib attached thereto;
[0033] FIG. 9 is a section view of the framing system with overlapping plank members;
[0034] FIG. 10 is a side section view of a plank member and end view of a frame member;
[0035] FIGS. 11-16 are alternate embodiments of the plank member;
[0036] FIGS. 17A-17G illustrate sketches of different rib profiles;
[0037] FIG. 18 is a section view illustrating a dovetail arrangement for the rib and receptor pocket;
[0038] FIG. 19 is a top view of a flat plate prior to being formed into a plank member;
[0039] FIG. 20 is an end view of a finished plank member;
[0040] FIG. 21 is a side view of the framing system being utilized for a wall; and
[0041] FIG. 22 is an end view of a framing member with a rib embedded therein.
DETAILED DESCRIPTION OF THE INVENTION
[0042] FIG. 1 illustrates the framing system 10 in accordance with the subject invention, while FIG. 2 illustrates an enlargement of the encircled portion of the framing system 10 in FIG. 1 . The framing system 10 is comprised of a plank member 15 having a front generally flat surface 17 and an opposing back surface 19 with at least one rib 20 protruding therefrom. A frame member 25 of an underlying structure 27 has at least one receptor pocket 30 extending therein. The rib 20 extending from the plank member 15 is matable with the receptor pocket 30 of the frame member 25 .
[0043] FIG. 3 is a side view of a portion of the framing system illustrating the manner by which the rib 20 of the plank member 15 engages the receptor pocket 30 of the frame member 25 . In particular, the rib 20 has a profile with a first side 35 and a second side 37 which diverge from one another as they extend away from the plank member 15 to which they are attached. Thereafter, they converge and connect with one another. The maximum height H of the rib 20 occurs at the place of maximum divergence. The receptor pocket 30 has a minimum width W less than that of the maximum height H of the rib 20 such that the rib 20 may be captured within the receptor 30 . It should be noted that while the rib 20 has a general shape of a teardrop, it will hereinafter be made clear that this shape is not to be intended as a limitation to the subject invention.
[0044] As illustrated in FIG. 1 , the plank member 15 and the frame member 25 are secured to one another through the engagement of the ribs 20 with the pocket receptors 30 .
[0045] In one embodiment of the subject invention, the rib 20 is resilient such that the rib 20 deforms in order to enter the receptor pocket 30 . Directing attention to FIG. 3 , the height H of the rib 20 would diminish so that the rib 20 would be able to enter the receptor pocket 30 . This may be achieved in one of at least two ways.
[0046] In particular, with attention directed to FIG. 4A , the rib 20 may have a hollow interior 40 such that a compressive force indicated by arrows 42 will deform the walls 44 of the rib 20 , as illustrated in FIG. 4B , such that the resultant height J is less than the width W of the opening within the receptor pocket 30 . Because the rib 20 is resilient upon entry within the receptor pocket 30 , the rib 20 will expand, thereby locking the plank member 15 within the frame member 25 . The walls 44 of the rib 20 actually bend to provide the resiliency of the rib 20 .
[0047] As illustrated in FIG. 5A , the rib 20 may also be made of a resilient material which itself compresses. In particular, FIG. 5A illustrates the rib 20 having a height H and subsequent to compressive forces 42 , the rib 20 , which may be solid, resiliently compresses to a height J as shown in FIG. 5B , sufficient to fit within the receptor pocket 30 .
[0048] It should be noted that the compressive forces 42 required to reduce the width of the rib 20 are those compressive forces generated by urging the plank member 15 against the receptor pocket 30 of the frame member 25 .
[0049] In yet another embodiment of the subject invention illustrated in FIGS. 6A and 6B , the receptor pocket 30 has receptor pocket walls 46 , 48 which initially have a width K and are expanded by the rib 20 having a height H such that the width K of the walls 46 , 48 expands to accommodate the height H of the rib 20 , as illustrated in FIG. 6B . Under these circumstances, the rib 20 is relatively rigid and the materials of the frame member 25 must be resilient.
[0050] Typical materials that may be used for the rib 20 may be structural metal of any kind, wood, wood composites, cementitious composites, plastic composites, structural steel composites, fiberglass, and carbon composites. It should be appreciated that this list is not exhaustive and that any material suitable for the application described herein may be suitable.
[0051] In each of these scenarios described in FIGS. 4A through 6B , at least one rib 20 or the receptor pocket walls 46 , 48 are rigid.
[0052] What has been discussed so far is a receptor pocket 30 within the frame member 25 and the rib 20 within the plank member 15 . Directing attention to FIG. 7 , it is entirely possible for the plank member 15 to have receptor pockets 50 while the frame member 25 has ribs 55 which engage the receptor pockets 50 in the manner previously described.
[0053] Directing attention to FIG. 8 , it is also possible for the rib 20 to be a separate piece 60 secured within the plank member 15 or, in the alternative, secured within the frame member 25 , which is not shown but is an obvious variation of the arrangement illustrated in FIG. 8 . The rib 20 may be secured to the plank member using any number of different fastener techniques. As an example, the rib 20 may have a threaded shank 62 which engages the plank member 15 .
[0054] FIG. 9 illustrates a cross-section view of one embodiment of the framing system 10 , whereby each plank member 15 has a recess 65 which is covered by an overhang 70 in an adjacent plank member 15 ′. Such an arrangement promotes retention of the plank member 15 within the frame member 25 .
[0055] FIG. 10 illustrates a side view of the framing system 10 , whereby the rib 20 of the plank member 15 is aligned to be engaged with a plurality of frame members 25 . A complete framing system 10 may be comprised of a plurality of plank members 15 arranged side-by-side over a plurality of spaced apart frame members 25 .
[0056] In one embodiment illustrated in FIG. 11 , the plank member 115 may have a tongue 117 on one side and a groove 119 on the other side which engage a mating groove 119 ′ in plank member 115 ′, and a mating tongue 117 ′ associated with plank member 115 ″.
[0057] It should be appreciated that one focal point of the subject invention is the interlocking ribs and receptor pockets. The plank member may embrace a variety of different designs to satisfy the different needs to which the framing system may be subjected.
[0058] FIG. 12 illustrates a plank member 215 having a generally oval cross-section with ribs 220 similar to those previously discussed extending therefrom.
[0059] The material of the plank member discussed herein may be wood, composite wood, metal, plastic or a carbon fiber composite. As an example, if the rib 220 of plank 220 is solid therethrough, then it is necessary for the material of the rib 220 to itself be resilient such that the rib 220 resiliently fits within the receptor pocket 230 of the frame member 225 . In the alternative, if the rib 220 has a hollow portion therein, then it is only necessary for the walls of the rib 220 to flex to fit within the receptor pocket 230 . Furthermore, as previously discussed, it is also possible for the receptor pocket walls to have resiliency themselves to accept a rib 220 .
[0060] FIG. 13 illustrates another variation of a plank member 315 having a front surface 317 and a back surface 319 with ribs 320 protruding therefrom. The variety of designs available for the plank member 315 are unlimited inasmuch as the back surface 319 has extending therefrom ribs 320 that may interlock with receptor pockets (not shown) of a frame member.
[0061] FIGS. 14, 15 and 16 illustrate further variations of plank members 415 , 515 , 615 , respectively, having back surfaces for 419 , 519 , 619 with ribs 420 , 520 , 620 extending therefrom. The designs illustrated in FIGS. 14-16 are of particular interest because these designs may be fabricated through extrusion processes using a variety of different materials including structural steel, structural metal, and structural plastic or other structural materials capable of being extruded.
[0062] The ribs 20 so far discussed have been in the general shape of a teardrop. A number of other rib shapes may be used inasmuch as these ribs may be snapped into the receptor pocket 30 of the frame member 25 . FIGS. 17A-17G illustrate a few such ribs 720 shapes. In each of these shapes, the first side 722 divergence from the second side 724 and then converges. As a result, these ribs 720 may snap into an approximately sized receptor pocket (not shown) located in the frame member. As illustrated in FIGS. 17F and 17G , each rib 720 may also resemble a barb 726 .
[0063] Briefly returning to FIGS. 1 and 2 , one method of attaching the plank member 15 to the frame member 25 is to press the plank member 15 against the frame member 25 such that the ribs 20 resiliently deform to engage the receptor pocket 30 or, in the alternative, a rib 20 engages the resilient walls 46 , 48 of the receptor pocket 30 until the rib 20 snaps into place within the receptor pocket 30 . It should be appreciated that, to the extent the rib 20 conforms with the shape of the receptor pocket 30 , it is possible to slide the plank member 15 into the frame member 25 such that the rib 20 engages the receptor pocket 30 without the need for resilient deformation. Under such circumstances, the plank member 15 slides into the frame member 25 from the side. Since the rib 20 is no longer required to resiliently fit with the receptor pocket 30 , the shape of these two elements may change.
[0064] Directing attention to FIG. 18 , a plank member 815 may have a rib 820 in the shape of a dove-tail which engages the frame member 825 through a receptor pocket 830 in the shape of a matching dove-tail. It should be appreciated that, while the shape of the dove-tail has been presented, any number of different positive locking shapes may be utilized for this arrangement.
[0065] The subject invention is also directed to a method of assembling a framing system 10 having a plank member 15 with the front generally flat surface 17 and an opposing back surface 19 with at least one rib 20 protruding therefrom or at least one receptor pocket 30 extending therein and having a frame member 25 of an underlying structure with the other of at least one receptor pocket 30 extending therein or at least one protruding rib 20 extending therefrom. The frame member rib 20 or pocket 30 is matable with the plank member pocket 30 or rib 20 . The method comprises the steps of aligning the ribs 20 with the receptor pockets 30 . The ribs 20 are then urged within the receptor pockets 30 until the ribs 20 snap into the pockets 30 . For this to occur, the rib 20 or the receptor pocket 30 must be resilient.
[0066] In an alternative embodiment, the method of assembling a framing system 10 would comprise the steps of aligning the rib 20 with the receptor pocket 30 and sliding the rib 20 within the receptor pocket 30 until properly positioned. Under these circumstances, it is not necessary for either the rib 20 or the receptor pocket 30 to be resilient.
[0067] So far illustrated is a frame member 25 having a generally C shape. Although other shapes may be utilized, this is a convenient shape that will typically be implemented for these structures. FIGS. 19 and 20 illustrate the method by which the frame member 25 is manufactured from a flat sheet 900 . In particular, openings 905 are punched within the flat sheet 900 , wherein at each end of the opening 905 is a slightly enlarged portion 910 which, in this instance, is designed to have the general shape of a rib 15 illustrated in FIG. 1 . Once the openings 905 are punched, the flat sheet 900 is then bent into a structural member having a top surface 915 and a bottom surface 920 , wherein the openings 905 extend within the top surface 915 to provide a receptor pocket 930 adapted to receive the protruding ribs 20 from the plank member 15 illustrated in FIG. 1 .
[0068] While FIGS. 1 and 2 illustrate the use of the framing system 10 for decking, the framing system 10 should not be limited to such applications and may be used in any application for which this design is appropriate. FIG. 21 illustrates the use of the framing system 10 as a fence or a wall. The framing system in accordance with the subject invention may have a multitude of other applications including use as a dock or an interior or exterior wall of a structure such as a building.
[0069] FIG. 22 illustrates a sketch whereby the rib 1020 is embedded within the frame member 1025 . This may be achieved by embedding the rib 1020 during an extrusion process used to form the frame member 1025 .
[0070] While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. The presently preferred embodiments described herein are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof. | A framing system has a plank member with ribs protruding therefrom and a frame member with a receptor pocket therein such that the rib of the plank member is resiliently engaged within the receptor pocket of the frame member to secure the plank member to the frame member. The plank member may also be laterally moved relative to the frame member such that the ribs slide within and engage the receptor pockets. The invention is also directed to a method for engaging the plank member with the frame member along with a method for fabricating the frame member. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to compounds having biological activity and to processes for the preparation thereof. The invention is particularly directed to compounds having anti-viral, particularly anti-HIV activity.
BACKGROUND TO THE INVENTION
[0002] The virus that causes AIDS, the human immunodeficiency virus HIV is believed to be one of the major threats to human life and health worldwide. Even back in 1988 an article in Scientific American by J. M. Mann, J. Chin, P. Piot and T. Quinn estimated that more than a quarter of a million AIDS cases had occurred in the U.S.A. up to then and that 5-10 million people were infected worldwide. An article in the same magazine ten years later “Defeating Aids: What will it take (July 1998 page 62) revealed that worldwide 40 million people had contracted HIV and almost 12 million had died leaving over 8 million orphans. During 1997 alone nearly 6 million people acquired HIV and some 23 million perished including 460,000 children.
[0003] Although 90% of HIV infected people live in developing countries well over 90% of money for care and prevention is spent in industrial countries. The very expensive triple therapy drugs (over US$10,000-$15,000 per person per year) are well beyond the reach of individuals in developing countries in sub Saharan Africa and Asia. In 1999 alone, 300,000 people died in Ethiopia from AIDS far exceeding deaths from famine (12 Apr. 2000, The Irish Examiner). Up to a quarter of South Africa's non-whites currently face death from AIDS in the next ten years (11 May 2000, The Irish Examiner, by G. Dyer). There is thus a desperate need for cheap, easily made and efficient anti-HIV agents for the developing world.
[0004] The HIV has been studied more intensively than any other virus and we now have a general picture of how the genes and proteins in the HIV virus particle operate, although we don't have a clear understanding of what controls the replication and how it destroys the human immune system. There are in fact many strains of HIV. The two main ones are HIV-1 and HIV-2. HIV-2 is prevalent in West Africa and produces a less severe disease than does HIV-1 the most common form elsewhere.
[0005] The life cycle of the virus is described below in some detail since for a drug to be effective it has to interfere with at least one stage of its life cycle. The HIV virus particle is roughly spherical shaped and is about a thousandth of a millimetre across. Its outer membrane consists of lipid molecules which possess many viral protein spikes projecting outwards. Each spike is thought to consist of four molecules of glycoprotein gp120 with the same number of glycoprotein gp41 molecules embedded in the membrane itself. These envelope proteins come into play when HIV binds and then enters target cells. Gp120 can bind tightly to CD4 proteins sited in the membranes of immune system cells especially T lymphocytes also called T cells. This is the first stage of the infection which is followed by fusion of the virus and T cell membrane, a process governed by the gp41 envelope protein. The result is that the contents of the virus core are thus freed to enter the cell. The virus core is surrounded by matrix protein called p17 and is itself in the shape of a hollow cone made of another protein p24 containing the genetic material of the virus.
[0006] Being a retrovirus this genetic material is in the form of RNA (ribonucleic acid) consisting of two RNA strands. These are in turn attached to molecules of an enzyme, reverse transcriptase, which transcribes the viral RNA into DNA once virus has entered the cell. Coexisting with RNA are an integrase, a protease, a ribonuclease and other enzymes. Once in the cell the viral RNA is converted to DNA which then enters the cell nucleus. The next step is integration of viral DNA into host chromosomes. This is followed by cell proteins binding to DNA initiating transcription. Short RNA molecules then leave the nucleus and make viral regulatory proteins followed by medium length and long RNA which generate structural and enzymatic proteins. These assemble to form new viruses (replication-viral budding) (1).
[0007] Prior to 1991 the only drug available to combat HIV/AIDS was Glaxo-Wellcome's AZT (zidovudine) a nucleoside analogue which works by binding to the reverse transcriptase enzyme thereby inhibiting viral replication. Unfortunately, long term use led to the virus developing resistance against the drug by mutation. New drugs in the same class were subsequently developed including 3TC (lamivudine) (Glaxo-Wellcome), ddc (zalcitabine) (Roche), ddl (didanosine)(Bristol-Myers Squibb), d4T (stavudine) (Bristol-Myers Squibb) and recently abacavir (Glaxo-Wellcome).
[0008] 1996 saw the introduction of a new class of drugs which acted at a different (and later) stage in the HIV virus' life cycle by blocking the action of the protease enzyme during viral replication. Furthermore, use of one of these with two of the class above (reverse transcriptase) gave viral loads in the blood being reduced by up to 4 log units or by a factor of ten thousand. Use of one drug alone reduces viral load by up to 2 log units or by a factor of one hundred. An effective example of this so called triple therapy would be use of AZT and 3TC (reverse transcriptase inhibitors) and indinavir (Merck Sharp and Dohme) or nelfinavir (Agouron) (protease inhibitors). Other protease inhibitors include saquinavir (Roche), ritanovir (Abbott laboratories) and amprenavir (Glaxo-Wellcome). In general, effective therapies employ two reverse transcriptase inhibitors together with one protease inhibitor.
[0009] 1996 also saw the introduction of another new class of drugs known as non-nucleoside reverse transcriptase inhibitors, the first being nevirapine (Boehringer Ingelheim) followed by delavirdine. (Pharmacia Upjohn) in 1997 then efavirenz (Du Pont) in 1998.
[0010] New effective therapies also capable of reducing viral loads by up to 4 log units or by a factor of 10,000 employ a combination of nucleoside and non-nucleoside reverse transcriptase inhibitors using a total of at least three drugs.
[0011] The cost of any triple therapy per patient per year is £10,000-£15,000. (2).
[0012] The following table gives an overview of current AIDS drugs, their type or class, effectiveness in reducing viral load, total amount of drug given to patient each day in number of doses, side-effects, time for viral drug resistance to develop when used alone, and approximate cost per patient per year. (2).
[0013] The first mentioned nucleoside reverse transcriptase enzyme inhibitor zidovudine (AZT) when used by itself has subsequently been shown to provide no benefits in treating HIV-infected individuals (3) although it is effective reducing transmission from mother to baby (4).
[0014] However, it can be effective when used in conjunction with other AIDS drugs such as 3TC, another nucleoside reverse transcriptase enzyme inhibitor (5).
[0015] Additionally, the HIV virus develops viral drug resistance against AZT rather quickly (5-6 months) when used alone and even more rapidly (1 and a half months) against 3TC when used alone (2). All nucleoside revere transcriptase enzyme inhibitors can cause serious side effects ranging from myopathy to peripheral neuropathy (nerve damage). The most recent drug abacavir's side effects can be life-threatening so treatment with this drug is immediately stopped at the first signs of any adverse reactions. Also ddc is a very toxic drug. Reduction in viral loads by drugs used on their own are only moderate 50-90% and their cost is quite high (£1,200-£10,000 per patient per year) (2).
[0016] The relatively recently developed non-nucleoside reverse transcriptase enzyme inhibitor AIDS drugs can cause severe skin reaction in patients and the HIV virus can develop viral drug resistance against them very quickly in 2 months in monotherapy (one drug). In addition, cross viral drug resistance has been noted using this class of drugs. In this case drug resistance against one drug in the class can cause drug resistance against another drug of the same class (2). Again used by themselves they only reduced viral load in patients by 50-90% and are relatively expensive (£1800-£2400 per person per year) (2).
[0017] The new protease enzyme inhibitors have to be given to patients in relatively large amounts (1250-2400 mg per clay) and can give serious side effects ranging from kidney stones to hepatitis and after prolonged use patients exhibit raised levels of cholesterol and triglycerides and can cause diabetes and abnormal distribution of body fat. In addition they are expensive (£4000-£7000 per person per year) (2). They are also generally poorly absorbed and have poor bioavailability which could well be related to their low water solubility (6), (Protease Inhibitors in Patients with HIV disease by M. Barry, S. Gibbons, D. Back and F. Mulcahy in Clinical Pharmacokinetics March 32 (3) 1997 p 194) and can interact with other protease enzyme inhibitors and nucleoside/non-nucleoside enzyme inhibitors in combination therapy, giving rise to a very strict order of oral dosing which must be adhered to by the patient (7) (Pharmacokinetics and Potential Interactions amongst Antiretroviral Agents used to treat patients with HIV infection by M. Barry, F. Mulcahy, C. Merry, S. Gibbons and D. Back, Clinical Pharmacokinetics, April 36 (4) 1997 p 289).
MARKETPLACE COMPARISON COST/ TOTAL PATIENT/ REDUCTION AMOUNT VIRAL DRUG YEAR IN VIRAL DRUG/DAY RESISTANCE (PUNTS) DRUG TYPE LOAD in (x) doses SIDE EFFECTS (MTHS) COMPANY Zidovudine nucleoside 50-90% 600 mg (2) myelosupression, 5-6 £7,000-£10,000 (AZT) reverse myopathy, nausea, Glaxo- transcriptase headache, anaemia Wellcome inhibitor Lamivudine nucleoside 50-90% 300 mg (2) gastrointestinal 1½ £7,000 (3TC) reverse disturbances, hair Glaxo- transcriptase loss, Wellcome enzyme myelosuppression, inhibitor exacerbation of peripheral neuropathy Stavudine nucleoside 50-90% 40 mg (2) peripheral greater than 6 £1,800 (d4T) reverse neuropathy Bristol transcriptase Myers enzyme Squibb inhibitor Didanosine nucleoside 50-90% 300-400 mg peripheral greater than 6 £2,000 (ddl) reverse (1) (at night) neuropathy, nausea Bristol transcriptase vomiting, pancreatis Myers enzyme Squibb inhibitor Zalcitabine nucleoside 50-90% 0.75 mg (1) very severe greater than 6 £1,200 (ddc) reverse (with meals) peripheral neuritis Roche transcriptase enzyme inhibitor Abacavir nucleoside 50-90% 300 mg (2) any reaction can be — £2,400 reverse life-threatening Glaxo- transcriptase always stopped Wellcome enzyme immediately inhibitor Nevirapinc non- 50-90% 200 mg (2) skin reaction 2 £1,800 nucleoside Boehringer reverse Ingelheim transcriptase enzyme inhibitor Delaviridine non- 50-90% 600 mg (3) skin reaction 2 £1,800 nucleoside many tablets Pharmacia- reverse Upjohn transcriptase (Agouron) enzyme inhibitor Efavirenz non- 50-90% 600 mg (1) skin reaction 2 £2,400 nucleoside Dupont reverse transcriptase enzyme inhibitor Indinavir protease 99% 2400 mg (3) hyperbilrubinaemia, 6 £5,000-£7,000 enzyme nephrolthiasis, Merck Sharp inhibitor nausea, kidney & Dohme stones, dizziness Ritonavir protease 99% 1800 mg (2) diarrhoea nausea, 6 £5,000-£7,000 (not used by enzyme vomiting, hepatitis, Abott itself) inhibitor headache Laboratories Saquinavir protease 99% 1800 mg (2) loose stools, nausea, 6 £5,000-£7,000 enzyme headache Roche inhibitor Nelfinavir protease 99% 1250 mg (2) a diarrohea, nausea 6 £4,000-£5,000 (Viracept) enzyme lot of tablets & vomiting Agouron inhibitor total 10 (Roche) Amprenavir protease 99% a lot of severe rash — £7,000 (can be used enzyme tablets Glaxo- with inhibitor Wellcome Ritonavir) All protease enzyme inhibitors raise patient's cholesterol, triglyceride levels and can cause diabetes, kidney stones and abnormal distribution of body fat after prolonged use.
[0018] The concentration at which an HIV-1 drug is effective is designated EC 50 μm which represents when the number of cells protected from HIV injection is half the total. The antigen Agp120 assay—the virus related antigen—is related to the number of virus particles produced by measuring glycoprotein gp120 in infected cell cultures. The concentration of the drug which reduces cell growth by 50% is designated TC 50 μM.
[0019] Of course the lower the EC 50 concentration the better but the real criterion of effectiveness in in vitro testing on cell cultures is the Therapeutic index which is the TC 50 /EC 50 ratio. The therapeutic index is selected so as not to damage healthy cells. Thus AZT has an EC 50 of ca 0.016 μM with a TC 50 >1000 μM. This results in a therapeutic index of >1000/0.016 ==>62,500. This figure serves as a benchmark against which new potential drugs can be measured. Of course human beings and animals are more than a collection of cells and in spite of the high Therapeutic Index, AZT is quite toxic, giving rise to nerve damage and anaemia among other things (2). Nevertheless, such tests on cell cultures indicate what is a potential anti-HIV drug.
[0020] Other factors relevant to the usefulness of an anti-HIV drug are physical properties such as water-solubility for drug absorption by the patient and stability of the compound after oral intake. Thus the potentially useful drug, the anionic polysaccharide, dextran sulphate is poorly absorbed orally and degrades after oral intake before entry into the plasma (8). Another important factor is the ease of synthesis of the drug and hence drug cost which is relatively high for AZT and most other drugs produced to date which are potentially useful in combating AIDS.
[0021] International Publication No. WO9403164 describes compounds having biological activity, particularly sulfonate based calixarenes, having anti-HIV activity.
[0022] International application No. PCT/IE01/00150 relates to compounds selected from the general group of compounds disclosed in international publication no. WO 95/19974 having especially surprising activity. It relates in particular to cyclic tetrameric pyrogallol-aldehyde derivatives and to calixarene derivatives which are useful in the treatment of AIDS. In particular, International application No. PCT/IE01/00150 discloses the dodecapotassium acetate of p-bromopyrogallol P—F-phenyl tetramer (AC-1 (Example 1 in PCT/IE01/00150)).
[0023] Further studies have been flied out on synthetic routes for AC-1 which demonstrate, rather surprisingly, that a non-brominated, partially alkylated analogue of AC-1 may be more active as an anti-AIDS drug than AC-1.
[0024] International Application No. PCT/IE01/00150 and International Publication No. WO 95/19974 do not teach the formation of a partially alkylated, non-brominated analogue of AC-1. Indeed, the problems associated with the complex step of selective alkylation during the synthesis of the compound disclosed herein teach away from the formation of a partially alkylated compound. In particular, the present invention relates to a tetra-alkylated non-brominated analogue of AC-1.
[0025] The present application also relates to the use of this non-brominated, partially alkylated compound in a pharmaceutical composition for the treatment of HIV-1.
[0026] There is a need for an anti-HIV drug which brings about a reduction in viral load but without causing the development of viral drug resistance and problems of toxicity. In short, a drug is needed which when given orally gives rise to at least a M.I.C. (Minimum inhibitory concentration) of drug in the blood against HIV but at a low enough concentration so as not to give rise to adverse side effects in the patient.
OBJECT OF THE INVENTION
[0027] It is an object of the present invention to provide novel and easily synthesised compounds having biological activity, particularly anti-HIV activity, particularly against HIV-1.
[0028] It is another object of the invention to provide a partially alkylated pyrogallol P—F-phenyl tetramer for use as an anti-Aids or anti-HIV agent.
[0029] It is a further object of the invention to provide compounds having a low EC 50 or MIC in patients blood (plasma) concentration which exhibit reduced and preferably little or no side effects, and bring about a reduction in viral load but without causing the development of viral drug resistance and pharmaceutical compositions thereof.
SUMMARY OF THE INVENTION
[0030] The invention provides compounds of formula I
wherein at least one R 1 is H and the remainder are CH 2 CO 2 K; R 2 is
and L is H.
[0031] The invention also provides compounds of formula I where 4 to 8 of R 1 are CH 2 CO 2 K, the remaining R 1 substituents are H, R 2 is
and L is H.
[0032] In one embodiment the invention provides a mixture of compounds of formula I having different degrees of alkylation. For example a mixture of compounds comprising tetra-alkylated and penta-alklyated compounds of formula I may be provided. Similarly, mixtures of compounds having between 6 and 8 alkyl groups may be provided.
[0033] In a preferred embodiment, the invention provides a compound of formula II
[0034] The compounds of formula I or II of the invention may be used in the preparation of a medicament for the treatment of viral infection, particularly HIV-1 infection.
[0035] The invention further provides a pharmaceutical composition comprising a pharmaceutically effective amount of a compound of formula I or II. The pharmaceutical composition may comprise at least one compound of formula I or II. The compounds of the present invention may be used in combination with pharmaceutically acceptable carriers or diluents to form pharmaceutical compositions for the treatment of viral infections, particularly HIV-1 infection.
[0036] In addition, the compounds according to the invention and in particular, mixtures of compounds of formula I having different degrees of alkylation may be used in combination with pharmaceutically acceptable carriers or diluents to form pharmaceutical compositions for the treatment of secondary infections/conditions associated with HIV-1 infection, as, well as the treatment of HIV-1 infections themselves.
[0037] The invention also provides for the use of compounds of formula I or II or a mixture of compounds of formula I; having different degrees of alkylation, together with an anti-viral agent in the preparation of a medicament for the treatment of viral infection, particularly HIV-1 infection. The tables below list examples of anti-viral agents that may be used.
Currently approved antiretrovirals (US FDA) Revers Transcriptase Inhibitors NRTI NNRTI Protease Inhibitors Retrovir Virammune Fortovase and Invirase (zidovudine: AZT) (nevirapine) (saquinavir) Epivir Rescriptor Norvir (lamivudine; 3TC) (delaviridine) (ritonavir) Combivir Sustiva Crixivan (AZT + 3TC) (efavirenz) (indinavir) Hivid Viracep (zalcitabine; ddC) (nelfinavir) Videx Ageberase (didanosine; ddl) (aprenavir) Trizivir Kaletra (abacavir + AZT + 3TC) (lopinavir + nitonavir) Zeril (starvudine, D4T) Ziagen (abacavir) Vired (tenofovit)
[0038]
Investigational antiretrovirals
Target
Inhibitor
Comments
HIV entry
Virus-cell Interaction
Soluble CD4
Toxin conjugated CD4
Mab to CD4 or gp120
PRO 542
Progenics Pharmaceuticals/GTC
Biotherapies
Dextran sulphate
Rersobene
FP-23199
Cyanovirin-N
Zintevir (T30177, AR177)
L-chicoric acid derivatives
Coreceptor
R5
Inhibitors
X4
Ligands
Modified ligands (R5)
Modified Ligands (X4)
Coreceptor
T22, T134
Inhibitors X4
ALX40-C
AMD3100
Bicyclam derivatives
Coreceptor
TAK-779
Inhibitors R5
SCH-C(SCH-351125)
SCH-D(SCH-350634)
NSC 651016
ONO Pharmaceutical
Merck (Fusion inhibitors)
Fusion Inhibitors
Fuzeon (T-20, DP 178, enfuvritide)
Roche/Trimeris
T-1249
Roche/Trimeris
TMC125
Tibotec
Integrase Inhibitors
5CITEP
L731,988
L708,906
L-870,812
S-1360
NCp7nucleocapsid
NOBA
Zn finger inhibitors
DIBA
Dithianes
PD-161374
Pyridinioalkanoyl thioesters
(PATES)
Azodicarbonamide (ADA)
Cyclic 2, 2 dithio bisbenzamide
RT Inhibitors
NRTI
Coviracil (emtricitabine)
Triangle Pharmaceuticals
DAPD (amdoxivir)
Triangle Pharm.
NNRTI
GW687
DPC083
TMC 125
Tibotec
Emivirine
Capravirine
BMS 561390
BMS
UC-781
(and other oxathiin carboxyanilides)
SJ-3366
Alkenyldiarylmethane (ADAM)
Tivirapine
Calanolide A
Sarawak MediChem
Pharmaceuticals
HBY097
Loviride
HEPT family derivatives
TIBO Derivatives
RNase H inhibitors
BBHN
CPHM
PD-26388
Protease Inhibitors
Atazanavir (BMS-232632)
BMS
Tipranavir
Boehringer Ingleheim
DMP450
Tat inhibitors
Dominant negative mutants
Ro24-7429
Ro5-3335
Rev inhibitors
Dominant negative mutants
Leptomycin E
PKF050-638
Transcriptional
Temacrazine
Inhibitors
K-12 and K-37
EM2487
Virus assembly/
CAP-1, CAP-2
Maturation
Cellular anti-HIV
LB6-B275, HRM1275
Targets
Cdk9 inhibitors
[0039] Further, the pharmaceutical composition according to the invention may comprise a compound of the invention together with a pharmaceutically effective carrier or excipient, and may be formulated as an injectable solution, a tablet, capsule, suppository or as a cream, gel or ointment for topical application.
[0040] The invention also provides a method of treatment of HIV infection comprising administering to a patient a pharmaceutically effective amount of at least one compound of formula I or II.
[0041] Further, the invention provides a method of treatment of infection comprising administering to a patient a pharmaceutically effective amount of at least one compound of formula I or II or a mixture of compounds of formula I having different degrees of alkylation. The compounds may be administered together with an anti-viral agent.
[0042] The invention will be described in greater detail with reference to the following examples.
DETAILED DESCRIPTION OF THE INVENTION
[0043] The present invention relates to non-brominated, partially alkylated pyrogallol calixarene type compounds and derivatives thereof. The compounds according to the invention may be prepared by selective alkylation of the cyclised calixarene type compound of the following formula
[0044] The difficulties associated with selective alkylation of cyclised calixarenes of the above formula will be appreciated by those skilled in the art. In particular, in the above cyclised calixarene there are twelve hydroxyl groups. Esterification can take place at twelve reaction sites. Some of the reaction sites are less reactive than others due to possible steric hindrance. It will be appreciated by those skilled in the art that several of the hydroxyl groups in the non-alkylated calixarene are hindered which could prevent alkylation occurring at these positions. Once the first alkyl group is alkylated the steric is hindrance is increased. Thus it will be further appreciated by those skilled in the art that such steric hindrance may prevent total alkylation occurring unless vigorous conditions are applied such as, for example, stirring under reflux for 72 hours using a large excess of alkylating agent. Thus following alkylation, the product can contain between 1 and 11 alkyl substituents.
[0045] It will further be appreciated by those skilled in the art that partially alkylated compounds such as those described herein may be prepared by selective alkylation incorporating the use of well known protecting groups.
[0046] Table 1 shows the activity of compounds which were prepared in the following examples and tested.
EXAMPLE 1
Preparation of Compound BC130202A
[0047]
(i) Preparation of Pyrogallol Calixarene:
[0048] To pyrogallol (40 g, 0.317 mole) in absolute ethanol (180 cm 3 ) was added p-fluorobenzaldehyde (39 g, 0.317 mole) and 37% HCL (aq.) (46.5 cm 3 ). The reaction mixture was stirred under reflux for five hours. After cooling, the solid precipitate was collected by filtration and washed with ethanol: water (4:1). The crude brown solid was then slurried under reflux in methanol, cooled, filtered and washed with cold methanol to yield 39 g (53%) of a grey/white solid.
[0049] (ii) Pyrogallol calixarene (14 g, 0.015 mole) was treated with potassium carbonate (12.44 g, 0.09 mole) and ethylbromoacetate (15.03 g, 0.09 mole) in acetone (150 cm 3 ). The reaction mixture was stirred at room temperature under a nitrogen atmosphere for seventy-two hours. The solvent was evaporated under vacuum and the residue treated with ca 2N HCl (aq) (100 cm 3 ). The resultant brown solid was slurried in methanol to yield a brown coloured solid (8.26 g, 43%).
[0050] (iii) The tetra-alkylated pyrogallol calixarene (6 g, 0.005 mole) in absolute ethanol (50 cm 3 ) was treated with KOH (6.6 g, 0.12 mole). The reaction mixture was stirred under reflux for two hours and filtered hot. The brown solid was washed with hot ethanol and dried in the oven to yield the product (7.26 g, 100%).
EXAMPLE 2
Preparation of BC010302B
[0051] Pyrogallol calixarene was prepared as outlined in Example 1 (i). Pyrogallol calixarene was then alkylated in accordance with the procedure outlined in Example 1 (ii) except six equivalents of ethylbromoacetate and potassium carbonate were used. Alkylation was carried out under reflux for three days. A mixture of compounds was obtained (BC010302B).
EXAMPLE 3
Preparation of BC010302B
[0052]
[0053] Pyrogallol calixarene was prepared as outlined above in Example 1 (i). Pyrogallol calixarene (9.30 g, 0.01 mole) in acetone (100 cm 3 ) was treated with potassium carbonate (11.05 g, 0.08 mole) and chloroacetic acid (7.5 g, 0.08 mole) in acetone (50 cm 3 ) added drop wise. The reaction mixture was stirred at room temperature under a nitrogen atmosphere over night. The solution was filtered, washed with acetone, slurried in methanol and acidified with conc. HCl. The solid was then slurried in ethanol and treated with KOH under reflux for 30 minutes to convert to the potassium salt. The solid was filtered and dried in a vacuum oven to yield 6.4 g of material.
EXAMPLE 4
Preparation of BC070202A
[0054]
[0055] (i) To resorcinol (5) (10 g, 0.091 mole) in absolute ethanol (40 cm 3 ) was added p-fluorobenzaldehyde (11.3 g, 0.091 mole) and 37% HCl (aq.) (13.5 cm 3 ). The reaction mixture was stirred under reflux for five hours. After cooling, the solid precipitate was collected by filtration and washed with ethanol: water (4:1). The crude brown solid was then slurried under reflux in methanol, cooled, filtered and washed with cold methanol to yield 11.3 g (53%) of a grey/white solid.
[0000] (ii) Alkylation
[0056] Resorcarene (4 g, 0.0046 mole) was treated with potassium carbonate (6.4 g, 0.046 mole) and ethylbromoacetate (7.72 g, 0.046 mole) in acetone (50 cm 3 ). The reaction mixture was stirred at room temperature under a nitrogen atmosphere for seventy-two hours. The solvent was evaporated under vacuum and the residue treated with ca 2N HCl (aq) (30 cm 3 ). The resultant brown solid was slurried in methanol to yield an off white coloured solid (63 g, 87% o).
[0000] (iii) Hydrolysis
[0057] The alkylated resorcarene (6 g, 0.004 mole) in absolute ethanol (40 cm 3 ) was treated with KOH (5.61, 0.1 mole). The reaction mixture was stirred under reflux for two hours and filtered hot. The white solid was washed with hot ethanol and dried in the oven to yield the product (6.31 g, ca. 100%).
EXAMPLE 5
Preparation of
[0058]
[0059] It will be appreciated by those skilled in the art that the above tetra-benzyl product could be prepared by a process analogous to Example 2 above.
EXAMPLE 6
Preparation of
[0060]
[0061] The above compound may be prepared by fully alkylating the tetra-benzyl product of Example 5 and then deprotecting by removing the benzyl groups and alkylating to form the above octa-alkyl product.
[0062] It will be appreciated by those skilled in the art that pre-alkylated pyrogallol such as shown below may be reacted with p-fluorobenzaldehyde to yield a definitive calixarene structure.
[0063] To prove the structure of the tetra-alkyl product shown above pre-alkylated pyrogallol intermediates for cyclisation are prepared. The intermediate (6) on cyclisation with 4-fluorobenzaldehyde can produce the tetra-alkyl ester, which on hydrolysis yields the tetra-alkyl product shown above.
[0064] Other possible products are analogous tetra-alkyl products (7). Preparation of these products requires the preparation of alternative tetramers using alternatives to 5-fluorobenzaldehyde. Based on the precedent already established, selective tetra-alkyation takes place. Alternatively, the alkylating agent can be varied to produce analogous products, to probe the activity requirement of the alkyl groups.
Clinical Results
Anti-HIV Activity
Determination of EC 50 and TC 50
Antiviral Assays
[0065] The concentration at which an HIV-1 drug is effective is designated EC 50 μm which represents when the number of cells protected from HIV injection is half the total.
[0066] The antigen Agp120 assay—the virus related antigen—is related to the number of virus particles produced by measuring glycoprotein gp 120 in infected cell cultures. The concentration of the drug which reduces cell growth by 50% is designated TC 50 μM.
[0067] Of course the lower the EC 50 concentration the better but the real criterion of effectiveness in in vitro testing on cell cultures is the Therapeutic index which is the TC 50 /EC 50 ratio.
[0000] gp 120 Antigen Assay
[0068] A microtiter antigen capture ELISA was developed using lectin (GNA) from Galanthus nivalis (Vector Laboratories, Peterborough, UK.) and human antibodies (10). The plates were coated with lectin (0.5 ug), and after blocking with 10% calf serum, dilutions of virus supernatant in 0.25% detergent solution (Empigen, Albright and Wilson Ltd., Whitehaven, UK.) were added to the wells and incubated at 4° C. for 12-16 hours. Bound antigen was captured using human anti-HIV antibodies, and finally detected with anti-human Ig antibodies conjugated to horseradish peroxidase.
[0069] A selection of compounds prepared in accordance with the preceding examples were tested and compared with an original sample of AC-1 (1151c). Two tests were performed: Test 1 was performed using infected blood, while Test 2 used cell cultures.
[0070] The results are shown in Table 1 which illustrates the activity of the compounds tested.
TABLE 1 Test 1 Test 2 Molecular EC 50 EC 50 Compound Description Weight (μM) (μg/ml) AC-1 Original Compound AC-1* 1850.2 0.5-1.0 4 (1151c) BC010302B Mixture of partially 1792.6 1.25 8 alkylated compounds of Formula I BC130202A Tetra-alkylated compound 1618.0 5.0 10 BC010302A Partially alkylated 1850.2 4-8(6) ≧40 compound of Formula I BC070202A Resorcarene 1633.8 75.0 ≧20 *corrected molecular weight
[0071] The results from both tests were comparable. The activity of BC010302B was comparable to that of the sample of AC-1 (1151c). The tetra-alkylated compound BC130202A was also active, demonstrating an EC 50 of 5 μM.
[0072] Of the two pure compounds, the AC-1 analogue BC130202A was slightly less active than the compound AC-1, while the resorcarene was much less active than the compound AC-1 (1115c).
TABLE 2 % inhibition of Conc gp120/CD4 Compound um binding 1151C 100 96 50 93 25 91 12.5 86 6.25 82 3.125 70 1.56 62 0.78 55 0.39 48 BC010302A 100 80 50 72 25 60 12.5 55 6.25 42 3.125 34 BC010302B 100 92 50 88.5 25 86 12.5 76 6.25 67 3.125 54 1.56 50 0.78 44 BC070202A 100 54 50 31 25 24 12.5 24 BC130202A 100 90 50 82 25 70 12.5 56 6.25 46 3.125 32 1.56 19 EC 50 represents the concentration which reduces the viral envelope protein gp120 interaction with the cellular receptor protein CD4 by 50% using recombinant proteins in an immunoassay format.
[0073] It has been shown that 1151c (AC-1) type compounds inhibit infection at an early stage of virus infection. This was confirmed by using recombinant proteins for the viral envelope and the cellular receptor. The proteins bind well in vitro using CD4 bound to plastic wells of 96 well plates. The results in the above table were obtained by carrying out the following procedure.
[0074] All stocks solutions were made 25 mM in distilled water and tested at same concentrations.
[0075] The procedure was carried out as follows:
1 Plastic plates were coated with cellular receptor protein CD4. 2 The plates were washed well before adding a predetermined, appropriate quantity of viral envelope protein gp120 for binding to CD4. 3 To see inhibition by compounds, different concentrations were added a few minutes before adding gp120. 4 The mixture was incubated at 37° C. for binding. 5 The plates were then flashed well and bound gp120 was detected by reaction with anti-HIV antibodies, incubated for 12 hours at 4° C. 6 The amount of antibody bound was detected by adding anti-Human antibodies attached to an enzyme horse raddish peroxidase. 7 After another incubation and wash, the quantity of the enzyme was measured by adding substrate o-phenyl diamine (OPD). 8 The colour developed was read at 492 nm. 9 All incubations took three days for adding different reagents. The percentage of inhibition by compounds, was calculated from the standard curve obtained by using different dilutions of gp120 alone.
Test 2
[0085] The results shown in Table 1 for test 2 were obtained by testing cell cultures in accordance with the following procedure.
[0086] CEM cells were suspended at approximately 250,000 cells per milliliter of culture medium and infected with wild-type HIV-1 (111 a ) at approximately 100 times the 50% cell culture infective dose (CCID 50 ) per milliliter. Then 100 μl of the infected cell suspensions were added to 200 μl microtiter plate wells containing 100 μl of an appropriate dilution of the test compounds. After 4 days incubation at 37° C. the cell cultures were microscopically examined for syncytium formation. The EC 50 (50% effective concentration) was determined as the compound concentration required to inhibit syncytium formation by 50%.
[0087] The results above demonstrate that a partially alkylated product compound as defined herein, in particular a tetra-alkyl product of formula I or a product of formula I containing 6 to 8 alkyl groups is required in order for the compound to be active. It will be appreciated by those skilled in the art that a partially alkylated product may be prepared by conducting selective alkylation under suitable reaction conditions.
[0088] The words “comprises/comprising” and the words “having/including” when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.
REFERENCES
[0000]
1. AIDS and the Immune System by W. C. Greene Scientific American 1993 p 67.
2. Drug Cocktails Fight HIV by L. Gopinath, Chemistry in Britain June 1997 p 38 and personal communications from Dr. Sam McConkey, Senior lecturer, Department of Medicine, Oxford University, United Kingdom and Dr. Peter Mugyenyi, Director Joint Clinical Research Centre, Kampala Uganda.
3. AZT Benefit in Doubt, Chemistry in Britain, May 1993, p 62.
4. Defeating AIDS: What will it take?, Scientific American, July 1998, p 62.
5. Potential Mechanism for Sustained Antiretro-viral Efficacy of AZT-3TC Combination Therapy by B. A. Larder, S. D. Kemp and P. R. Harrigan. Science vol. 269, 4 Aug. 1995, p 696.
6. Protease Inhibitors in Patients with HIV Disease by M. Barry, S. Gibbons, D. Back and F. Mulcahy in Clinical Pharmacokinetics, March 32 (3) 1997 p 194.
7. Pharmacokinetics and Potential Interactions amongst antiretroviral agents used to treat patients with HIV infection by M. Barry, F. Mulcahy, C. Merry, S. Gibbons and D. Back, Clinical Pharmacokinetics, April 36(4) 1999 p 289.
8. Molecular Targets for AIDS therapy by H. Mitsuya, R. Yarchoan and S. Broder, Science 28 Sep. 1990 p 1533.
9. N. Mahmood, A. J. Hay (1992) An ELISA utilizing immunobilised snowdrop lectin GNA for the detection of envelope glycoproteins of HIV and SIV. J. Immunol Methods 151:9-13.
10. R. Pauwels, J. Balazarini, M. Baba, R. Snoeck, D. Schols, p. Herdewijn, J. Desmyter and E. De Clerq, (1988) Rapid and automated tetrazolium based colorimetric assay for the detection of anti-HIV compounds. J. Virol Methods 20:309-321. | Compounds of formula I
wherein at least one R 1 is H and the remainder are CH 2 CO 2 K; R 2 is
and L is H are described. The compounds are useful as pharmaceutical compositions in the treatment of AIDS. | 2 |
FIELD OF THE INVENTION
The present invention relates to devices for providing medical gas and electrical services to hospitals and other medical care facilities.
BACKGROUND OF THE INVENTION
Construction costs for hospitals and other medical care facilities depend in part on the cost of required medical equipment as well as the efficiency of installation of such equipment during the construction phase. One major item installed in most patient care areas is a wall panel for providing medical gases and electrical services at the bedside. Modular assemblies for such panels have simplified installation of these services. Nevertheless, there remains a need to simplify the production and assembly of these units, and to provide greater efficiency in the installation of the units at the construction site. Further, there is a need for modular in-wall type units that provide a more compact, vertically oriented interface for users. Still further, there is a need for a vertically oriented in-wall unit with convenient equipment management capabilities.
SUMMARY OF THE INVENTION
The present invention comprises a modular in-wall medical services unit for installation in the wall of a structure. The structure has at least a first room with a floor and a ceiling level and a wall at least partially defining the first room. The wall comprises a wall space defined at least in part by wallboard. The unit comprises a frame having a first side. The frame is sized to extend from the floor to above the ceiling level of the structure and adapted to be installed in the wall space of the structure.
A first medical service outlet is supported on the frame to be between the floor and the ceiling level of the structure. The first service outlet is positioned to be accessible from the first side of the frame. A first service conduit is supported on the frame to extend from the first service outlet to above the ceiling level of the structure. A first service connection is included. The service connection is operatively connected to the first service conduit and supported on the frame to be above the ceiling level of the structure and to extend from the first side of the frame forward of the wall space into the first room so as to be accessible after installation of the wallboard.
Further, the present invention comprises modular in-wall medical services unit for installation in the wall of any one of a plurality of structures, wherein each of the structures has a first room, a floor and a wall space, and wherein each of the structures has a different ceiling level. The unit comprises a frame having a length adjustable to extend from the floor to above the ceiling level of any of the plurality of structures. The frame is adapted to be installed in the wall space of the structure. A first medical service outlet is supported on the frame to be between the floor and the ceiling level of all of the plurality of structures. The first service outlet is positioned to be accessible from the first side of the frame in the first room.
Still further, the present invention includes a modular in-wall medical services unit for installation in the wall of a structure having a first room defined in part by a wall having a wall space covered by wallboard. The unit comprises a frame adapted to be installed in the wall space of the structure. The frame has a first side for the first room. A first mounting flange is provided on the frame and is adapted to be connected to the edge of wallboard in the first room. A first cover panel is supported on the first side of the frame. A first trim flange on the cover panel, generally parallel to the first mounting flange on the frame, is positioned forwardly of the first mounting flange a distance sufficient to receive wallboard therebetween during installation of the unit.
A first medical service outlet is supported on the first side of the frame to be accessible in the first room through the first cover panel. The first trim flange is movable horizontally relative to the first mounting flange during installation of the wallboard between a first position and a second position. In the first position, the first trim flange is spaced a distance forward of the wallboard between the first mounting flange and the first trim flange. In the second position, the first trim flange engages the wallboard.
Further still, the present invention is directed to modular in-wall medical services unit for installation in the wall of a structure having a first room with a floor and a ceiling level and a wall at least partially defining the first room, wherein the wall comprises a wall space and wallboard forming the wall's exterior surface. This unit comprises a frame having a first side. The frame is adapted to be installed in the wall space of the structure. Also included is a vertically oriented cover panel supported by the frame, the cover panel having a height and a width, the height being greater than the width. The cover panel comprises a pair of vertically-oriented side edges.
A first medical service outlet is supported on the frame and accessible through the cover panel on the first side of the frame from within the first room. A trim flange is provided along at least a portion of at least one of the vertically-oriented side edges of the cover panel. The trim flange is adapted to join the side edge of the cover panel to the wallboard. The trim flange defines a vertically oriented equipment-mounting track therein. The cover panel is positioned on the frame so that when the frame is installed in the wall space, the first service outlet and the equipment-mounting track are positioned to be used conveniently by a human operator standing in the first room.
Finally, the present invention comprises a modular in-wall medical services unit for installation in the wall of a structure having a first room with a floor and a ceiling level and a wall at least partially defining the first room, the wall comprising a wall space. The unit comprises a frame having a first side. The frame is adapted to be installed in the wall space of the structure. The frame supports a vertically oriented cover panel. The cover panel has a height and a width, the height being greater than the width. The height of the cover panel is less than the distance between the floor and the ceiling level of the first room.
A first medical service outlet is supported on the frame and accessible through the cover panel on the first side of the frame from within the first room. The cover panel is positioned on the frame so that when the frame is installed in the wall space, the first medical service outlet is positioned to be conveniently used by a human operator standing in the first room.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational, fragmented view of hospital room showing the modular medical services unit of the present invention installed in the wall near a bed.
FIG. 2 is an elevational, fragmented view of the hospital room shown in FIG. 1 with the wallboard cut away to reveal the installation of the unit between the wall studs of the wall space.
FIGS. 3A and 3B are a longitudinal sectional view taken along line 3 - 3 of FIG. 2 .
FIG. 4 is a fragmented, cross sectional view taken along line 4 - 4 of FIG. 2 . The service outlets have been omitted for clarity of illustration.
FIG. 5 is a fragmented, exploded cross sectional view of a portion of the cross section of the unit shown in FIG. 4 .
FIGS. 6 and 7 are fragmented longitudinal sectional views taken through a portion of the unit through the cabinet illustrating how the cabinet is slidably mounted to move forward and rearward in the main frame of the unit.
FIGS. 8-10 illustrate the steps employed to install the wallboard around the unit and attach the trim flange along the exposed edges of the unit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to the drawings in general and to FIG. 1 in particular, there is shown therein a modular medical services unit constructed in accordance with the present invention and designated generally by the reference numeral 10 . As used herein, “medical service” or “service” refers to any one of a variety of gas, electrical or communication services, including but not limited to oxygen, compressed air, vacuum (suction), electricity, telephone and video cable. The unit 10 is illustrated installed in the wall 12 of at least a first room 14 in a structure 16 . Usually, the unit 10 will be installed at the side of a patient bed 18 . While a conventional hospital room is depicted, the unit 10 may be installed in a variety of structures such as clinics, emergency rooms, nursing home rooms, and virtually any sort of treatment facility.
As shown in FIGS. 2 and 3 A- 3 B, the unit 10 is adapted for installation in the wall space 20 defining the first room 14 . Preferably, the unit comprises a frame 22 sized to be installed between wall studs 24 in the wall space 20 defined by wallboard 28 . More preferably, the frame 22 is sized to extend from the floor 30 to a distance above the ceiling level 32 of the room 14 .
In the preferred embodiment, the frame 22 comprises a main frame assembly 34 and a top frame assembly 36 . The main frame assembly 34 preferably comprises a pair of C-shaped vertical rails 38 stabilized by one or more cross rails 40 ( FIGS. 2 , 3 B). Similarly, the top frame assembly 36 is shorter in length but formed of a pair of opposing C-shaped vertical rails 44 and at least one stabilizing cross rail 46 ( FIGS. 2 , 3 A).
The vertical rails 38 and 44 may be formed from sheet metal having a thickness sufficient to provide the necessary rigidity to the unit 10 . For example, in a preferred construction, the metal of which the rails are made may be only about 1/16 inch. Conventional wallboard typically ha a thickness of about ⅝ inch. However, for clarity of illustration, the thickness of the metal in the vertical rails 38 and 44 , as shown in FIGS. 3A and 3B is exaggerated relative to the thickness of the wallboard.
As best seen in FIGS. 3A-3B , the corresponding C-shaped vertical rails 38 and 44 of the main frame assembly 34 and the top frame assembly 36 may be telescopically engaged so that the overall height or length of the frame 22 can be adjusted. To that end, a plurality of vertically arranged holes 50 and 52 are provided in the vertical rails 38 and 44 , respectively. A bolt 54 or fastener of some sort may be used to secure the vertical rails 38 and 44 at the desired length.
At least a first cabinet 56 is supported in the frame 22 , preferably in the main frame assembly 34 between the vertical rails 38 . When the unit 10 is to be used in a wall space shared by a second room 58 , the unit may be functional on both first and second sides 60 and 62 , as seen in FIGS. 3A and 3B . Thus, a second cabinet 64 may be supported in the frame 22 back-to-back with the first cabinet 56 .
The first cabinet 56 preferably provides a divided enclosure to house the medical service outlets. The service outlets preferably include a first plurality of electrical outlets designated generally at 70 , including at least first electrical outlet 72 , and a first plurality of gas outlets designated generally at 74 , including at least a first gas outlet 76 on the first side 60 of the frame 22 . Similarly, the second cabinet 64 preferably provides a divided enclosure to house medical service outlets. More preferably, the service outlets in the second cabinet 64 comprise a second plurality of electrical outlets designated generally at 80 , including at least a second electrical outlet 82 , and a second plurality of gas outlets designated generally at 84 , including at least a second gas outlet 86 on the second side 62 of the frame 22 . Thus, the gas and electrical outlets and other service outlets are supported on the frame to be positioned between the floor 30 and the ceiling level 32 of the structure 16 and accessible from the first and second sides 60 and 62 of the frame 22 when the unit 20 is installed.
Referring still to FIGS. 2 and 3 A- 3 B, the unit 10 also preferably includes medical service conduits, such as a first plurality of electrical conduits designated generally at 88 including at least a first electrical conduit 90 supported on the frame 22 . The conduits 88 extend from the first electrical outlet 72 up through the main frame assembly 34 to a point in the top frame assembly 36 above the designated ceiling level 32 . As used herein, “electrical conduit” denotes generally the tubular conduit and the wires contained in it.
Also included in the unit is at least one medical service connection for each medical service conduit. For example, in the preferred unit 10 , the service connections include at least a first electrical junction box 92 preferably supported in the top frame assembly 36 and positioned to be above the ceiling level 32 and to extend from the first side 60 of the frame 22 forward of the wall space 20 into the first room 14 (not shown in FIG. 2 ). In this way, the electrical service connection will be accessible before and after the wallboard 28 is installed. The junction box 92 is operatively connected to at least the first electrical conduit 90 .
The service conduits may include gas conduits in addition to electrical conduits. To that end, the unit 10 preferably also comprises at least a first plurality of gas conduits 94 including a first gas conduit 96 supported on the frame 22 to extend from the first gas outlet 76 to a point above the ceiling level 32 of the top frame assembly 36 . The upper end of the gas conduit 96 preferably is bent outwardly or provided with an elbow fitting to provide a gas service connection forward a distance of the wall space 20 once the unit 10 is installed. In this way, the gas connection will also be accessible before and after the wallboard 28 is installed.
As seen in FIGS. 3A and 3B , the unit 10 may also include a second plurality of electrical conduits designated generally at 98 including at least a second electrical conduit 100 extending from the second electrical outlet 82 on the second side 62 of the frame 22 up through the main frame assembly 34 to a point in the top frame assembly 36 above the designated ceiling level 32 . At least a second junction box 102 may be supported in the top frame assembly 36 back-to-back with the first junction box 92 , also positioned to be above the ceiling level 32 and to extend from the second side 62 of the frame 22 forward of the wall space 20 into the second room 58 . Alternately, a single junction box may be utilized, in which case all the electrical conduits will be connected to the single junction box.
As shown in FIG. 1 , a part of the unit 10 remains exposed when fully installed in the first room 14 . This part preferably comprises a cover panel that supports the faces of the various electrical and gas service outlets. More preferably, the cover panel is vertically oriented, that is, it is taller than it is wide, or has a height greater than its width. Most preferably, the cover panel is positioned on the frame 22 so that when the frame is installed in the wall space 20 , the medical service outlets are located for convenient use by a human operator standing in the first room 14 .
A first cover panel 110 covers the first cabinet 56 on the first side 60 of the frame 22 . Likewise, as seen in FIG. 3B , a second cover panel 112 covers the second cabinet 64 on the second side 62 of the frame 22 .
The dual-sided unit 10 further preferably includes a second plurality of gas conduits 106 including a second gas conduit 108 . The second plurality of gas conduits 106 and the second gas conduit 108 , as on the first side 60 , are supported on the second side 62 of the frame 22 to extend from the second plurality of gas outlets 84 and the second gas outlet 86 , respectively, to above the ceiling level 32 of the structure 16 .
The preferred installation of the unit 10 provides for the wallboard 28 to be cut to fit closely around and behind the vertically oriented side edges 114 and 116 ( FIG. 2 ) of the cover panels 110 and 112 . For that purpose, a trim and flange combination is provided to provide a secure installation and an attractive facade for the unit 10 . A detailed description of this trim and flange assembly will be made with reference to FIGS. 4 and 5 , to which attention now is directed.
FIG. 4 is a fragmented cross-sectional view taken through one end (the left end as viewed in FIG. 2 ) of the main frame assembly 34 of the unit 10 . FIG. 5 is an exploded view of one corner of the end shown in FIG. 4 . The outlet assemblies have been omitted to clarify the illustrations.
The left vertical rail 38 comprises a planar central portion 120 arranged to be positioned generally transverse to the wall space 20 . Extending laterally from the central portion 120 are first and second opposing mounting flanges 122 and 124 positioned to be generally co-planar with the wallboard 28 to be applied.
The depth of the frame 22 , that is, the width of the central portion 120 is selected to conform to the depth of the wall space 20 . In this way, when fixed in position between the wall studs 24 (see FIG. 2 ), the central portions 120 of the rails 38 (and the corresponding central portions of the rails 44 in the top frame assembly 36 ) can be used conveniently to attach the frame 22 to adjacent studs 24 . The flanges 122 and 124 provide elongated vertical mounting flanges positioned to abut and support the interior side of the wallboard 28 around the cover panels 110 and 112 ( FIG. 3B ).
The first and second cabinets 56 and are slidably attached to the central portion 120 and the vertical rail 38 by the bolts 126 and 128 in a manner to be described hereafter. Trim flanges 130 and 132 are extruded edge members attached to the vertical sides of the cabinets 56 and 64 . While this attachment can be accomplished in various ways, in the present embodiment, the trim flanges 130 and 132 include inward extensions 134 and 136 that extend inwardly to overlap the sidewalls 138 and 140 of the cabinets 56 and 64 and attached thereto by bolts 142 and 144 .
The trim flanges 130 and 132 further preferably comprise extensions 146 and 148 to underlay the edges of the cover panels 110 and 112 . Bolts 150 and 152 attach the extensions 146 and 148 to the cover panels 110 and 112 . The trim flanges 130 and 132 include legs 154 and 156 . The legs 154 and 156 are configured to be generally parallel to but spaced a distance forward of the mounting flanges 122 and 124 . Bolts 158 and 160 are included to extend through the legs 154 and 156 and mounting flanges 122 and 124 and the wallboard 28 sandwiched therebetween.
With continuing reference to FIGS. 4 and 5 , vertical cover strips 166 and 168 preferably are provided to cover the trim flanges 130 and 132 and the bolts 158 and 160 . Like the trim flanges 130 and 132 , the cover strips 166 and 168 preferably are extrusions. More preferably, the cover strips 166 and 168 comprise angled strips having side portions 172 and 174 and front portions 176 and 178 . The side portions 172 and 174 provide sections to receive small screws 180 and 182 to attach the cover strips 166 and 168 to the trim flange legs 154 and 156 .
Equipment mounting tracks 184 and 186 conveniently be provided in the front portions 176 and 178 of the cover strips 166 and 168 . More preferably, the racks 184 and 186 are integrally formed in the extruded strips 166 and 168 . Thus, in addition to the other advantages of the unit of the present invention, the trim flanges 130 and 132 of the cover panels 110 and 112 include the convenience of built-in equipment management. Moreover, like the medical service outlets also contained in the cover panels 110 and 112 , these mounting tracks 184 and 186 , will be conveniently accessible by a human operator standing in the first room 14 .
The sliding or moving connection between the cabinet/cover panel/trim flange assembly relative to the frame 22 is shown in more detail in FIGS. 6 and 7 . While other types of connections are suitable, in the present embodiment the movable connection comprises an elongated horizontal slot 190 formed in the sidewall 138 of the cabinet 56 to receive the bolt 126 . (See also FIG. 5 .) The allows the cabinet 56 to be moved forwardly and rearwardly, or horizontally relative to the frame 22 , between a first and second position.
The advantage of the movable connection shown in FIGS. 6 and 7 is illustrated in FIGS. 8-10 . In FIG. 8 , the cabinet 56 and attached cover panel 110 are pulled forward to the first position to provide a space 196 between the leg 154 of the trim flange 130 and the surface of the wallboard 28 . In this position, it is easy to run a bead of sealant 198 in the space 196 . Next, as seen in FIG. 9 , the cabinet 56 and attached cover panel 110 are pushed back to the second position forcing the trim flange 130 against the face of the wallboard 28 to engage the wallboard 28 . The bolt 158 then is installed. FIG. 10 illustrates the attachment of the cover strip 166 with the attachment screw 180 .
Having described the construction of the unit, the use will be summarized. The unit, as delivered to the construction site, preferably has the cabinets mounted inside the frame. The cabinets, conduits and junction boxes are secured to the frame. The height of the frame will have been adjusted at the factory to accommodate the specified ceiling level of the room into which the unit is to be installed. The cover panels are secured over the front of the cabinets with the trim flanges on the long vertical edges between the cover panels and the cabinets. The cabinet and attached cover panels will be slightly movable or “floating” on the frame, and the cover strips will be separate or separable from the trim flanges.
After unpacking the unit, the unit will be placed in the wall space between two studs, and the vertical rails of the frame are secured to the partition system. Next, the cabinet/cover panel assembly is pulled to its outward most position and the wallboard is installed. The wallboard may be installed around the cover panel and all the way up to deck above the ceiling level. That is, the wallboard may be installed over the top frame assembly of the unit, leaving the service connections, such as the junction boxes and the ends of the gas conduits accessible.
Once the wallboard is installed, there is still a space between the face of the wallboard and the trim flange around the cover panel. If desired, a bead of caulk or sealant is applied. Next, the cover panel is pushed back against the wallboard, forming a seal between the edge of the wallboard, the trim flange and the sealant therebetween. Now it will be seen that the floating connection allows the cabinet assembly to be self-aligning; it will meet the wall surface closely from top to bottom regardless of irregularities in the wallboard surface of lack of plumb in the wall studs.
Next, screws are inserted through the trim flange, through the wallboard and into the mounting flange of the frame behind it, to hold the wallboard securely between the cover panel in front and the mounting flange of the frame behind it. Finally, the cover strips may be attached over the trim flanges and end caps may be attached at the bottom and top edges of the cover panel for a finished appearance.
Now it will be appreciated that the modular medical services unit of the present invention provides several advantages at both the manufacturing level as well as at the point of installation. The frame is constructed of two rail assemblies joined by an easily adjustable telescoping arrangement. These main structural components can be manufactured and kept in inventory. Upon receipt of an order specifying a specific ceiling level, the unit can be assembled quickly and adjusted to the appropriate length. The length is selected so that the attached gas conduits and junction boxes will be above the ceiling level. The elbow connections on the gas conduits extend the connections out into the space forward of the wallboard. Likewise the junction boxes are positioned forward on the frame so that the front closure on the boxes can be accessed even after the wallboard is installed. Thus, there is no need for the installation of the wallboard to be delayed until the electrical work or piping can be completed.
A further advantage of the unit of this invention is found in the manner in the way the cover panel is attached to the unit. When delivered to the construction site, the trim flange on the cover panel, and typically the entire cover panel, is movably attached to the frame or cabinet providing a self-aligning feature during installation. This floating connection allows the cover panel to be pulled out slightly to apply a bead of caulk or sealant around the opening in the wallboard before the cover panel is fully secured to the wallboard and frame. A further advantage is found in the vertical equipment mounting tracks provided in the vertical cover strips.
Changes can be made in the combination and arrangement of the various parts and steps described herein without departing from the spirit and scope of the invention. | A modular in-wall medical services unit for medical care facilities. A frame supports a cabinet with a cover panel providing electrical and/or gas outlets. Built-in electrical and gas conduits are included. A junction box and ends of the gas conduits near the top of the frame are accessible after wallboard is applied. Thus, wallboard can be installed before or after wiring is completed and gas connections are made. The self-aligning cover panel is “floatingly” supported on the frame so that a bead of sealant can be applied around the edge before the cover panel is “snugged up” to the wall and secured. The trim flanges on the cover panel include vertical equipment mounting tracks. Manufacturing is simplified by making the height of the frame adjustable; the same frame elements can be used to assemble units for different ceiling heights, decreasing the number of required parts in inventory and expediting assembly. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. application Ser. No. 08/729,446, filed Oct. 11, 1996, now abandoned.
BACKGROUND
1. Field of the Invention
The invention generally concerns an apparatus for raising and lowering boats, and more particularly relates to an improvement employing flotation elements which can be raised and lowered by means of pumping water in or out, with the entire apparatus being adjustable to accommodate boats of different dimensions.
2. Discussion of the Prior Art
Apparatus of the general type to which the present invention relates is known from German patent 4,214,019, for example. According to this known publication, the hull of the ship to be raised is run onto a floating cushion that is subsequently inflated to raise the hull out of the water.
German patent 4,426,194 discloses another device for raising boats in water, where the known floating cushion principle is also combined with a magnetic holding device that is in contact with a (metallic) ship's hull and is secured there with suitable magnetic plates.
German utility model GM 9,312,336 concerns another device that is also based on the principle of a float that can be flooded and vented.
All these known apparatuses have in common the fact that their object is to raise a hull floating in water out of the water so the hull is raised above the water line while docked.
This concept offers some major advantages for winter boat storage since boats that are used with the known devices need no longer be dry docked. Likewise, these designs also have advantages because the underwater paint is exposed to water only when the hull is actually in use.
However, the known devices have the disadvantage that they do not keep the hull safe enough from accidents. In particular, there is a lack of stability when pumping up a boat--in other words, when lifting the hull out of the water.
Especially with the device according to German patent 4,214,019, the center of gravity of the boat is precisely in the middle of the inflatable cushions, which has the disadvantage that when the hull is lifted, it tends to tilt to the side.
A disadvantage of German patent 4,426,194 is that the float should be in contact with the outside of the hull, thus leading to a great increase in the total required width of the entire device, which consequently takes up a great deal of space in the water, although that is not desirable.
SUMMARY OF THE INVENTION
A primary purpose of this invention is therefore to improve on a device of the above-mentioned type so that a boat can be raised out of water reliably, much more easily and less expensively, so that the boat can be docked above the water line (without any danger of canting), and furthermore the usable width of the device as a whole is greatly reduced.
An important feature of the invention is that now at least two floats are provided at the sides of a support that is intended for accommodating the keel in the longitudinal direction. These floats are connected to the support in a stationary or displaceable mount and the entire device is secured to a mooring point in such a way that it is adjustable in height.
This improvement to the conventional technical teaching has the important advantage that the support mentioned above is now connected at the side directly to corresponding floats running longitudinally. This yields the advantage that the support is used almost exclusively to accommodate the keel part of the boat, and the floats connected to it can be in direct contact with this area of the keel, so this greatly reduces the resulting width of the device.
This yields the further advantage that the entire device corresponds essentially only to the width of the boat, because the floats below the ship are in contact with the ship's hull in the area of or next to the keel line and it is no longer necessary for these floats to be in contact with the side walls of the ship's hull.
In a preferred embodiment of the present invention, the connection between the support that accommodates the keel and the respective floats that are held in a separate framework is designed to be adjustable in height. This results in the important advantage that the height of lift of the hull out of the water can be adjusted with this adjustable height option. This makes it possible to design the support to accommodate keel boats (such as sailboats) but also (with an appropriate reduction in the depth of immersion) this support can also be adjusted to accommodate motor boats with a relatively shallow keel in water. Thus, this support is intended to accommodate mainly leisure boats, such as motor boats, sailboats, rowboats, pedal boats, etc.
Another important feature of this invention is that now the device according to this invention is designed for being attached to adjacent devices at the side. In other words, several similar devices are joined at the sides in such a way that they are adjustable in height (so they can be displaced vertically relative to each other), and these units float in water independently of each other and are designed to be submersible and liftable, but fact that one device is connected to the next device at the side has the advantage that on the whole the devices are protected from lateral canting, and the canting protection of such a device is greatly improved in this way.
It is important here for the devices that are positioned side by side to be connected to each other in such a way that each device can move vertically in the water independently of the others, so appropriate displacement guides are provided for this purpose and may consist of suitable roller guides, for example, where a suitable roller arrangement is provided on one device to engage in a vertical track in the neighboring device.
Another embodiment of this height adjustment device consists of the fact that a suitable dovetail guide is provided to engage in a matching guide in the neighboring device. Likewise, tongue-and-groove devices or similar methods of engagement are also provided.
When the apparatus of the invention is being used, the floats are first flooded and the entire device is below the water line such that the support for accommodating the keel of a corresponding float is lowered just as deeply in the water. In this submerged position, the pillars, which are now preferably provided only at the mounts for the floats, project out of the water. These pillars are also preferably each provided with a hand rail running longitudinally. Thus, this is a type of boat dock that, when submerged, can be recognized only by its pillars projecting vertically out of the water and the optional hand rails running parallel to the water surface.
The ship's hull to be raised is first guided into the submerged device, where the pillars arranged on both sides assure that the hull is centered well over the submerged support, and at the same time the ship can also be secured to the pillars. However, this invention is not limited to the use of such pillars, which could be eliminated.
It is also assumed here that the entire device is tied to a relatively stationary point (mooring point). Such a mooring point may be a pier, a buoy, a floating jetty, a pile, etc. It is also preferable if the entire device is attached to this pier or mooring point in such a way that it is adjustable in height so a constant relationship of the device to the stationary mooring point can be achieved at all times. This connection is preferably designed with an articulated joint or at least so it is adjustable in height to assure that the connection to this mooring point will be maintained even when the device is submerged.
Once the hull has been guided into the submerged device, it is no longer necessary to tie the hull to the side pillars because it is sufficient to center the hull between the pillars. Furthermore, it is not essential to this invention for the pillars to be in contact with the hull.
As soon as the hull has been centered on the device, several pumps that are suitable for emptying the floats that were previously filled with water and are started and pump the water out of these floats. These are preferably inexpensive electric submersible pumps that are available in several designs.
The floats may be subdivided into several successive compartments, where a submersible pump is provided for each compartment. This makes it possible to flood individual segments of the floats, so it is possible to adjust a certain inclined position of the device submerged in water. This also makes it possible to adjust the floating level of the device submerged in water, just as the floating level of the device out of water can also be adjusted later.
Operating the submersible pumps thus removes the water from the floats in order to assure a precisely defined floating level of the entire device in water. The hull is then raised out of the water and lifts the body of the ship out of the water. In summer, the keel and the rudder will remain in the water, whereas in the winter the height adjustment device on the support can be adjusted so that all underwater parts of the hull can be completely raised out of the water. This has the advantage that the apparatus (as a boat dock) can remain in water and the entire boat hull has a winter dock in water.
Therefore, this device has the advantage that in summer the underwater hull of the boat comes in contact with water only when the boat is actually in operation, but the underwater hull does not come in contact with water for the remainder of the docking time. This prevents the environmentally harmful antifouling paints from coming in contact with water except when the hull is actually being used for leisure and sports purposes.
Another advantage of this invention is that only additional fastening devices for tarpaulins or canvas can be attached to the hand rails, thus resulting in a floatable and submersible boat dock. Therefore, it is no longer necessary to cover the hull itself with canvas or tarpaulins because such a cover can be attached to the boat dock itself in a stationary mount.
Such a device can also be equipped for single-handed operation. In this case, a control cable is stretched between the pillars, spanning the width of the device. Then when the hull is guided into the receiving space of this device, the bow of the boat encounters this control cable, which then tightens. This control cable may be arranged on rails running longitudinally so they guide the bow in the longitudinal direction and center it over the support, and simultaneously with the tightening of this control cable, the pump for emptying the floats may be activated, so, in addition, the entire device is raised into its elevated position at the same time.
The floats mentioned above are safe for use in ice and are preferably made of aluminum or plastic bodies, rubber elastic bodies or thin steel bodies. The other parts of the device are preferably made of aluminum, iron or plastic sections.
When several of these devices are combined, they can form a complete docking system, so it is now much easier to dock a variety of boats in one dock system.
Another advantage of the entire device is that winter dry docks can now be eliminated and can be replaced with winter docks in water, where only a relatively low depth suffices for these devices to assure that the boat will be in a suitable raised position. Even if the water level drops during the winter, floatability of the device is still assured.
Another advantage of this device is that the boat is much more theft-proof because the pumps and their electric power supply can be permanently secured and then it is no longer possible to steal the boat when it is out of water.
In another preferred embodiment of the invention, the height adjustment device for boats consists only of two tubes that accommodate the hull and are arranged so they are parallel to each other and stationary at the external distance of the ship's greatest width--on a pier, for example--and these tubes can be raised by means of the respective pumps and can be lowered by flooding, so a boat can remain docked on these tubes above the water level throughout the year when the tubes have been pumped empty. This boat lift yields the important advantage that it costs the boat owner much less than a winter dock and furthermore it is no longer necessary to apply antifouling paint, and finally is it not necessary to remove algae from the underwater hull.
Additional advantages for the boat owner include the fact that it is no longer necessary to set the mast, and transportation from the pier to the winter dry dock and back again is eliminated. Similarly, no crane fees are necessary, nor is there any risk of osmosis.
In addition, the boat need not be occupied when docking, and instead it can be docked single-handedly. A boat docked in this way is sea-ready with just a couple of manipulations, and the underwater hull can be inspected without raising it with a crane. This preferred boat lift can also be equipped with a burglar alarm.
This embodiment of the present invention also has some significant advantages for the dock operator because now the dock can be leased out even in the winter, and the winter dry dock areas can be utilized more profitably, especially in the area of the pier.
Maintenance work on boats can now be distributed uniformly throughout the year, thus preventing bottlenecks, especially in the spring and fall.
With this boat lift system, boats can be docked closer together and a dolphin is no longer necessary.
Finally, it is also possible to use these boat lift systems as displacement systems, so more boats can be accommodated in a given area of water.
This preferred boat lift system also has some important advantages for environmental protection, since there are no longer any toxic paints to pollute drinking water, no toxins enter the environment when sanding and washing the underwater hull when the boat is docked on these tubes and furthermore the buoy fields can be arranged in docking islands with this boat lift system.
BRIEF DESCRIPTION OF THE DRAWING
The objects, advantages and features of this invention will be more clearly understood from the following detailed description, when read in conjunction with the accompanying drawing, in which:
FIG. 1 is a front view of apparatus constructed according to this invention;
FIG. 2 is a side view of the apparatus of the invention as seen in the direction of arrow II in FIG. 1;
FIG. 3 is a top view of the invention taken in the direction of arrow III in FIG. 2;
FIG. 4A is a section through a displacement mount with a dovetailed guide for the pillar shown in FIGS. 1-3;
FIG. 4B is a section through an alternative displacement mount having a tongue-and-groove guide for the pillar shown in FIGS. 1-3;
FIG. 4C is a side view of the embodiment of the FIGS. 1-3 apparatus, not showing the boat's hull taken in the direction of arrow IV in FIG. 5;
FIG. 5 is a top view of the apparatus of FIG. 4 taken in the direction of arrow V;
FIG. 6 is a sectional view taken along cutting plane VI--VI in FIG. 5;
FIG. 7 is a sectional view taken along cutting plane VII--VII in FIG. 5;
FIG. 8 is a perspective view of an alternative embodiment of the device according to the invention, having synchronization;
FIG. 9 is a side view of a pillar of the invention shown in FIG. 8;
FIG. 10 is a top view of the device according to FIG. 8, where some of the components are not shown for purposes of clarity;
FIG. 11 is a top view of two interlinked roller boxes of the invention shown in FIG. 8;
FIG. 12 a side view of a rotary disk shown in FIG. 10;
FIG. 13 a view of a buoy with two chains as employed in the invention; and
FIG. 14 is a diagram of a float portion of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference now to the drawing, the apparatus consists essentially of a lower central, submersible support 1 that in turn consists of two parallel longitudinal bars 3 connected together by cross arms 4 at certain intervals. Keel pillar 5 is provided between longitudinal bars 3 and is designed so it is adjustable in the longitudinal direction between the longitudinal bars.
Ship's hull 2 with its underwater hull and keel 33, if any, is then run onto support 1. There are a plurality of generally vertical pillars 6 that project upwardly from longitudinal bars 3 and have supporting plates 7 on the free upper ends to form a cradle means to support the hull of a boat. Appropriate diagonal or transverse braces 6' may also be provided from pillars 6 to cross arms 4 according to FIGS. 1 and 2. Side gusset plates 8 may also be provided on the outside of pillars 6, where they are attached to the pillars and are suitable for attaching appropriate floats 10, 11. These floats on either side of the support are an important aspect of the invention and accommodate the keel in the longitudinal direction.
Each float 10, 11 extends approximately over the entire length of the device and is attached to side pillars 12, 14 with additional external gusset plates 9. The embodiment illustrated in FIG. 1 shows how floats 10, 11 may be made of hexagon lal or polygonal sections, for example. Another embodiment is also illustrated in FIG. 1 where floats 10', 11' may be designed with a round or cylindrical shape. They may also be oval, elliptical or any other desired shape. The only important thing is that they should have compartments that are preferably separated from each other, where each compartment has its own pump 30 (see FIGS. 4 and 6). For example, FIG. 4 shows float compartments 10a and 10b.
Pillars 12, 14 project upwardly and are adjacent to side gusset plates 9. Pillars 12 are longitudinally centrally located and are connected directly to support 1, while pillars 14 are adjacent the longitudinal ends of the apparatus and connected to floats 10, 11. The connection between support 1 and floats 10, 11 is also established by two cross arms 24, 25 that are longitudinally spaced from each other.
Front pillars 14 are attached to front cross arm 24 and displacement mount 18 to which bracket 17 is attached is also provided on these pillars. Bracket 17 is arranged so it is adjustable in height on front pillar 14 and it is attached to mooring point 34 which is external of the apparatus of the invention. This connection to the mooring point may be referred to as an articulated joint. The mooring point may be geographically stationary, or relatively stationary with respect to the support of the invention.
FIG. 1 also shows that similar neighboring devices can be connected to the device shown with solid lines in FIG. 1 by an appropriate displacement mount or linking means 19, where this displacement mount assures a mutual adjustability in height of the devices that are coupled together. The neighboring devices are merely indicated schematically by floats 10', 11' and the respective pillars 14'.
FIG. 2 illustrates the raised position of the device because most of the hull of the boat (except for keel 33) is above water line 13. This also shows that pillars 12, 14 are connected to each other by hand rails 15 running in the longitudinal direction.
The rear part of the device that extends into the water is stabilized by buoy 16 or by another float. In the embodiment illustrated here, chain 21 passes through central recess 20 in buoy 16 and through borehole 22 provided in horizontal extension 35 of the lower base point of pillar 14. Chain 21 has lower stop 23.
When the entire device is flooded by pumping water into the different chambers of floats 10, 11 using pumps 30, the entire device sinks into the water together with carriers 35 that have boreholes 22. Then stop 23 comes to rest against the under side of carrier 35, because it will not pass through borehole 22, and now floating buoy 16 supports the rear part of the device in the submerged state and thereby stabilizes the entire device.
According to FIG. 3, it is also important that the neighboring device uses the same buoy 16, so the device has right and left buoys 16, 16', and each buoy is also shared by the neighboring device, which is connected directly to the device described above by displacement mount 19 so it is adjustable in height, as mentioned above. Also shown in FIG. 3 is a reference length scale represented as a line with spaced numerals 0-9. The length could be in meters or some other convenient unit.
FIGS. 4A and 4B show two other possibilities of guiding pillars 14 and 14' in displacement mount 18 and 19. FIG. 4A shows the possibility of a dovetailed guide which has the advantage that pillars 14 and 14' are connected displaceably but undetachably to displacement mount 19. Pillars 14 and 14' are pillars of adjacent devices. FIG. 4B shows a tongue-and-groove guide for pillars 14 and 14' in displacement mounts 18, 19.
Furthermore, the entire usable width of the device can be adapted to the given boat width because of the fact that cross arms 24, 25 are designed so they are adjustable in the direction of arrows 26, 27 (FIG. 6) and have appropriate securing options.
FIG. 6 also shows that submersible pumps 30 have appropriate outlets 31 through which the water is pumped out of the corresponding compartments of floats 10, 11. Likewise, pumps 30 and outlets 31 incorporate means for appropriate venting and aerating to assure that air is drawn into the floats as the water is pumped out. Fenders 28 are preferably arranged on the inside of pillars 12, but they need not necessarily be in contact with the hull of the boat itself.
Appropriate diagonal struts 29 may be provided between cross arms 24, 25 for reinforcement purposes. A similar strut arrangement could be provided between longitudinal bars 3, if desired.
To adapt the depth of immersion of the device to different depths of the boat hull 2 to be raised, FIG. 7 shows that the entire support 1 with its side pillars 6 is attached to inside gusset plates 8 by means of height adjustment devices 32. This makes it possible to adjust the depth of immersion of the support to the depth of the hull for each individual boat.
FIG. 8 is a perspective view of a device according to this invention with synchronization. This synchronization prevents tilting in raising/lowering. Additional details of the synchronization are shown in FIGS. 9 and 10.
Adjacent devices are connected to one another over at least four roller boxes 36, three of which are shown in FIG. 8. The roller boxes 36 reach around adjacent pillars 14, 14' of adjacent devices, as detailed in FIG. 11, and are essentially undisplaceable with respect to water line 13 (see FIG. 9).
As shown in FIGS. 9-13, each roller box 36 is connected at its bottom to a traction mechanism 37, for example, a cable or a chain, and at its top to a traction mechanism 38, which could also be a cable or a chain. Traction mechanisms 37, 38 are deflected over rollers 39 and extend over the entire displaceable length of pillar 14. They are guided over additional rollers 39 to a rotary disk 40 (FIG. 10), which is mounted on cross arm 25 so that it can rotate in the direction of arrows 44, 45. For the sake of a better overview, traction mechanisms 38, which are attached to the top of roller boxes 36, are shown with dotted lines in FIG. 10. Rollers 39 can be attached to floats 10, 11 at struts 41 or at other parts.
If the entire device is to be raised in the direction of arrow 42, shown in FIG. 13, floats 10, 11 are filled with air or water is pumped out. The resulting buoyancy causes a displacement of pillars 14 in the direction of arrow 42. This automatically exerts a tensile force on the lower traction mechanisms 37, which turns rotary disk 40 in the direction of arrow 44 accordingly. Due to this rotation, the top traction mechanisms 38 are released, and pillars 14 can move upward in the direction of arrow 42.
The changes in length or, to be more precise, the displacement paths of traction mechanisms 37, 38, are identical here. The individual pillars 14 are linked by traction mechanisms 37, 38. Thus vertical synchronization occurs and it is impossible for one pillar 14 to be raised more quickly or more slowly than the other pillar 14. Tilting is thus reliably prevented.
For lowering in the direction of arrow 43, floats 10, 11 are flooded, and the process takes place in the opposite order, with rotary disk 40 being turned in the direction of arrow 45. Synchronization is thus also operative in lowering.
Roller boxes 36 remain essentially at the same level with respect to water line 13 because of traction mechanisms 37, 38. They serve as fixed points for raising and lowering a boat. Roller boxes 36 have the same function as displacement mounts 18, 19 according to FIGS. 1-3 and they can replace them.
FIG. 11 shows two roller boxes 36 linked together. This coupling is desirable in one embodiment, because in this way, any desired number of devices can be arranged side by side. Each roller box 36 is essentially cuboid in design with a recess 53, which is suitable for accommodating a pillar 14. Each roller box 36 is also provided with at least two rollers 54 which are mounted so they can rotate in roller box 36. Pillars 14 are supported on these rollers. In raising or lowering a boat, rollers 54 are rotated, so that pillars 14 can move in roller boxes 36 with almost no friction.
FIG. 12 shows a side view of a rotary disk 40. Rotary disk 40 must accommodate a total of eight traction mechanisms 37, 38, namely two per corner pillar 14, with two mechanisms being reeled in or unreeled jointly. Therefore, it is sufficient to arrange a total of four receptacles 55, one above the other, on rotary disk 40. Rotary disk 40 is mounted on a shaft 56 which is in turn mounted on cross arm 25 so that the disk can rotate in the direction of arrows 44, 45.
Each receptacle 55 can accommodate two traction mechanisms 37 and 38. Only one type of traction mechanism, that is, either traction mechanism 37 or traction mechanism 38, is accommodated in each receptacle 55. Either traction mechanism 37 or 38 which acts on the same side of rotary disk 40 can be combined, or opposing similar traction mechanisms 37 and 38 which then cover one another can be combined.
FIG. 13 shows a view of a buoy 16 which is suitable for use with two devices arranged side by side. Buoy 16 has a central recess 20. Two chains 21, 21' which are mounted on a fastener 47 run in central recess 20. The right chain 21 serves for a first device, the left chain 21' serves for another device which is linked to the former. Both devices extend around chain 21, 21' with their respective carriers 35, 35'. One weight 46, 46' is provided for tightening each chain 21, 21'. It is clear that the two devices can be raised and lowered independently of one another in the direction of arrows 42, 43.
FIG. 14 shows a float 10, 11. Float 10, 11 is subdivided into two essentially identical chambers 48 separated by a watertight partition 50. At least one water-permeable baffle 49 is provided in each chamber 48. These baffles serve to retard movement in chamber 48 of water accommodated in chamber 48. Each chamber 48 also has a connection 51 for supplying compressed air and a valve 52 for flooding chamber 48. All connections 51 and all valves 52 are preferably operated together to permit rapid raising or lowering.
In view of the above description, it is likely that those skilled in the art will envision modifications and improvements in this invention. The invention is limited only by the spirit and scope of the accompanying claims, with due consideration being given to a reasonable range of equivalents. | Apparatus for raising and lowering boats in water. The apparatus consists essentially of at least one float that is attached to the hull of the boat and is guided along the surface of the hull of the boat at least partially below water level when a force is applied to it. Preferably at least two floats that are permanently or displaceably attached to the apparatus support in the longitudinal direction and are provided on the side of the support which is intended to accommodate the hull of a boat. The entire device is designed so it is adjustable in height and is connected to a stationary land-based mooring point with an articulated joint. This device is especially reliable for raising a boat out of the water and docking the boat above the water line without risking canting. This result is possible in an inexpensive and very simple manner with the invention. The usable width of the entire device is greatly reduced from previously known such devices. | 1 |
[0001] This application is a Divisional of Ser. No. 10/906,552, filed Feb. 24, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates generally to semiconductor devices, and more particularly, to a method of forming low capacitance back end of the line (BEOL) wiring, and the structure so formed.
[0004] 2. Related Art
[0005] When forming CMOS, BiCMOS, SiGe, and other similar devices, it is desirable to minimize capacitance. Likewise, there is a continuing desire in the industry to reduce device size. Therefore, there is a need in the industry for a method of forming a semiconductor device that addresses these and other issues.
SUMMARY OF THE INVENTION
[0006] The present invention provides a method of forming a semiconductor device having a low wire capacitance and a high wire resistance, and the structure so formed, that solves the above-stated and other problems. The device comprises conductive wires having widths substantially smaller than the width of the printed and etched trench and/or via formed for the wire.
[0007] A first aspect of the invention provides a method of forming a semiconductor device, comprising: providing a substrate; depositing a first dielectric layer; depositing a hard mask on the first dielectric layer; forming an at least one first feature within the first dielectric layer and the hard mask; depositing a conformal dielectric liner over the hard mask and within the at least one feature, wherein the liner occupies more than at least 2% of a volume of the at least one feature; depositing a conductive material over the liner; and planarizing a surface of the device to remove excess conductive material.
[0008] A second aspect of the invention provides a method of forming a semiconductor device, comprising: providing a substrate; depositing a first dielectric layer; forming an at least one feature within the first dielectric layer; depositing a conformal dielectric liner over a surface of the device and within the at least one feature, wherein a thickness of the liner is at least approximately ⅓ a minimum width of the at least one feature; and metallizing the at least one feature.
[0009] A third aspect of the invention provides a semiconductor device, comprising: a substrate; a first dielectric layer on a surface of the substrate; a hard mask on the first dielectric layer; at least one first feature within the first dielectric layer and the hard mask; a conformal dielectric liner over the hard mask and within the at least one feature, wherein the liner occupies more than at least 2% of a volume of the at least one feature; and a conductive material within the at least one feature.
[0010] A fourth aspect of the present invention provides a method of forming a structure, and the structure so formed, comprising a dual damascene structure wherein a via of the dual damascene features may be formed having a width equal to, or up to ⅓ less than, a minimum trench width, and wherein a thickness of a conformal dielectric liner within the feature occupies more than at least approximately 2% of the feature volume.
[0011] The foregoing and other features and advantages of the invention will be apparent from the following more particular description of the embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The embodiments of this invention will be described in detail, with reference to the following figures, wherein like designations denote like elements, and wherein:
[0013] FIG. 1 depicts a cross-sectional view of a device comprising a first dielectric layer, a first hard mask and a photoresist layer thereon, in accordance with embodiments of the present invention;
[0014] FIG. 2 depicts the device of FIG. 1 having trenches formed therein;
[0015] FIG. 3 depicts the device of FIG. 2 having a conformal liner thereon;
[0016] FIG. 4 depicts the device of FIG. 3 following an etch back process;
[0017] FIG. 5 depicts the device of FIG. 4 following metallization;
[0018] FIG. 6 depicts the device of FIG. 5 following planarization;
[0019] FIG. 7 depicts the device of FIG. 6 having a second dielectric layer, hardmask and photoresist layer;
[0020] FIG. 8 depicts the device of FIG. 7 having a plurality of trenches formed therein;
[0021] FIG. 9 depicts the device of FIG. 8 having a conformal liner thereon;
[0022] FIG. 10 depicts the device of FIG. 9 having a photoresist layer thereon;
[0023] FIG. 11 depicts the device of FIG. 10 following photoresist patterning;
[0024] FIG. 12 depicts the device of FIG. 11 having a plurality of narrow vias formed within the trenches;
[0025] FIG. 13 depicts the device of FIG. 12 following metallization;
[0026] FIG. 14 depicts the device of FIG. 13 following planarization;
[0027] FIG. 15 depicts the device of FIG. 11 having a plurality of wide vias formed within the trenches;
[0028] FIG. 16 depicts the device of FIG. 15 following metallization;
[0029] FIG. 17 depicts the device of FIG. 16 following planarization;
[0030] FIG. 18 depicts the device of FIG. 11 following photoresist patterning;
[0031] FIG. 19 depicts the device of FIG. 18 having a plurality of vias formed therein;
[0032] FIG. 20 depicts the device of FIG. 19 having a conformal liner deposited over the device;
[0033] FIG. 21 depicts the device of FIG. 20 having a plurality of layers deposited over the liner;
[0034] FIG. 22 depicts the device of FIG. 21 following photoresist patterning;
[0035] FIG. 23 depicts the device of FIG. 22 following etching;
[0036] FIG. 24 depicts the device of FIG. 23 following additional etching;
[0037] FIG. 25 depicts the device of FIG. 24 having trenches formed therein;
[0038] FIG. 26 depicts the device of FIG. 25 having a conformal liner deposited thereover;
[0039] FIG. 27 depicts the device of FIG. 26 following etching;
[0040] FIG. 28 depicts the device of FIG. 27 following metallization; and
[0041] FIG. 29 depicts the device of FIG. 28 following planarization.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] Although certain embodiments of the present invention will be shown and described in detail, it should be understood that various changes and modifications might be made without departing from the scope of the appended claims. The scope of the present invention will in no way be limited to the number of constituting components, the materials thereof, the shapes thereof, the relative arrangement thereof, etc. Although the drawings are intended to illustrate the present invention, the drawings are not necessarily drawn to scale.
[0043] FIG. 1 depicts a semiconductor device 10 having a substrate 12 , which may comprise conventional features (not shown), such as, a plurality of shallow trench isolations (STI), a MOS transistor and spacers, a vertical NPN transistor, a plurality of contacts damascened into a dielectric, etc., as is known in the art. The substrate 12 is preferably substantially planar, as shown in FIG. 1 .
[0044] In accordance with the present invention, a first dielectric layer 14 is deposited over a surface of the substrate 12 . The first dielectric layer 14 may comprise a dielectric material having a low dielectric constant (k), wherein “low k” is defined as a dielectric constant (k) below 3.0, or in the range of approximately 1.5-2.7, such as porous poly(areylene) ether (e.g., porous SiLK™ (Dow Chemical)), porous SiCOH, porous SiO 2 , teflon, amorphous carbon, etc. The first dielectric layer 14 may be deposited using chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), spin-on deposition, etc., to a thickness of approximately 150-200 nm.
[0045] A hard mask 16 is then deposited over the first dielectric layer 14 . The hard mask 16 may comprise a dielectric material, such as SiC, SiCN, SiCOH, SiO 2 , Si 3 N 4 , etc. The hard mask 16 may be deposited using CVD, PECVD, etc., to a thickness of approximately 1-100 nm, e.g., 10 nm. The hard mask 16 protects the first dielectric layer 14 during subsequent processing, and is optional.
[0046] A photoresist 18 is then applied over the hard mask 16 , as illustrated in FIG. 1 . The photoresist 18 may be applied to a thickness in the range of approximately 50-3000 nm, e.g., 200 nm. The photoresist 18 may comprise a positive or negative photoresist 18 as desired. The photoresist 18 is patterned, and the first dielectric layer 14 and hard mask 16 are etched using standard back end of the line (BEOL) exposure and reactive ion etch (RIE) formation techniques to form trenches 20 a , 20 b ( FIG. 2 ). Narrower trenches 20 a may be formed having an aspect ratio (height:width) in the range of approximately 2:1, and a minimum trench width 22 a in the range of approximately 100-150 nm. Wider trenches 20 b may be formed having any width, and a wide range of aspect ratios, e.g., an aspect ratio of approximately 1:2, 1:10, etc. The wider trenches 20 b may also be formed with an optional “dummy fill” in the very large trenches 20 b (e.g., a width greater than 2 microns) to reduce the patterned factor, as known in the art.
[0047] During the standard BEOL formation process the photoresist 18 may be completely consumed during the RIE etch used in conjunction with a p-SiLK first dielectric layer 14 , as illustrated in FIG. 2 . Alternatively, a multi-layer hard mask may be used (not shown), such as a first lower hard mask layer, (SiC), and a second upper hard mask layer, (SiO 2 ). When using the multi-layer hard mask set the SiO 2 is patterned and etched down to the SiC. The photoresist used to pattern the SiO 2 is removed. The SiO 2 is then used to pattern and etch the SiC. The remaining combination of SiO 2 and SiC are then used to pattern the underlying first dielectric layer 14 , as known in the art.
[0048] As illustrated in FIG. 3 , a conformal dielectric liner 24 is deposited over the surface of the device 10 . The liner 24 may comprise a dielectric material having a low dielectric constant (k), wherein “low k” is defined as a dielectric constant (k) preferably below 3.0, or in the range of approximately 1.4-4.5, such as SiCOH, SiO 2 , poly(areylene) ether (e.g., SiLK™ (Dow Chemical)), teflon, or other similarly used material. The liner 24 may be deposited using PECVD, CVD, or other similar deposition techniques. The liner 24 may have a thickness up to approximately ½ the width of the minimum trench width 22 a , and preferably ⅓ the width of the minimum trench width 22 a ( FIG. 2 : 100-200 nm), i.e., a thickness in the range of approximately 30-50 nm. As a result, the liner 24 occupies more than at least 2% of a trench volume, e.g., at least 50%, or more, of the trench volume. The liner 24 must be prevented from “pinching off” (filling in the opening of the trenches 20 a , 20 b ) which would prevent subsequent metallization of the trenches 20 a , 20 b.
[0049] A spacer etch back process is performed to remove a portion of the liner 24 from a base 31 of the trenches 20 a , 20 b , while leaving the liner 24 on the sidewalls 33 of the trenches 20 a , 20 b , as illustrated in FIG. 4 .
[0050] As illustrated in FIG. 5 , a conductive liner 26 , a seed layer 28 and a conductive layer 30 are deposited during a standard metallization process. The conductive liner 26 may be deposited over the surface of the device 10 using sputtering techniques, such as plasma vapor deposition (PVD), ionized plasma vapor deposition (IPVD), self-ionized plasma (SIP), HCM, chemical vapor deposition (CVD), atomic layer deposition (ALD), metal organic chemical vapor deposition (MOCVD), etc. Likewise, the seed layer 28 may be deposited over the conductive liner 26 using similar sputtering techniques, i.e., PVD, IPVD, SIP, HCM, CVD, ALD, MOCVD, etc. The conductive liner 26 may comprise one or more refractory metals or alloys, such as Ta, TaN, TiN, W, WN, TaSiN, WSiN, or other similarly used material. The conductive liner 26 may have a thickness in the range of approximately 1-200 nm, e.g., 5 nm. The seed layer 28 may comprise a copper seed material, or other similarly used material for the subsequent electroplating deposition. The seed layer 28 may have a thickness in the range of approximately 1-200 nm, e.g., 20 nm. The conductive layer 30 may comprise copper, or other similarly used material. The conductive layer 30 may be formed having a thickness in the range of approximately 50 nm-5 microns, e.g., 200 nm. It should be noted that the conductive liner 26 and the seed layer 28 are not drawn to scale for purposes of illustration.
[0051] Following deposition of the metallization, (the conductive liner 26 , the seed layer 28 and the conductive layer 30 ), a planarization process is performed to remove the excess metallization on the surface of the device 10 . A chemical mechanical polish (CMP) or other similarly used process may be used to planarize the surface of the device 10 . The planarization process is performed down to the conformal dielectric liner 24 , as illustrated in FIG. 6 . Alternatively, the planarization process may be performed down to the hard mask 16 (not shown). A first metal wiring level 44 , having a plurality of electrically conductive wires 32 a , 32 b therein, in this example comprising a single damascene wiring structure, is produced following the planarization process.
[0052] As illustrated in Table 1, infra, the present invention produces a device 10 having a capacitance far lower, and a wire resistance much higher, than that of similar devices formed using conventional formation methods.
TABLE 1 Comparison of Capacitance and wire Resistance measurements normalized to the Conventional Device A. BEOL device dielectric layer 14 liner 24 Line-to-Line Capacitance (wire dimensions) Resistance Capacitance between wiring (aspect ratio) per micron per micron levels per micron Conventional Device A. SiCO (k = 2.7) 1 1 1 (140 nm × 200 nm) (1.4:1) Present Invention B. p-SiLK (k = 2.2) 5 0.4 0.7 SiCOH liner (k = 2.7) (50 nm × 150 nm) (3:1) C. p-OSG (k = 1.6) 5 0.3 0.5 SiCOH liner (k = 2.7) (50 nm × 150 nm) (3:1) D. p-OSG (k = 1.6) 20 0.15 0.3 SiCOH liner (k = 2.7) (25 nm × 75 nm) (3:1) (* The “p-” indicates that the dielectric is a porous dielectric. The “k” stands for dielectric constant.)
[0053] As illustrated by examples B-D under the “Present Invention” in Table 1, using a low k dielectric material for the first dielectric layer 14 , in conjunction with a low k dielectric liner 24 reduces the overall capacitance of the device 10 and increases the wire resistance. In fact, the lower the dielectric constant (k) of the first dielectric layer 14 the more the capacitance of the device is reduced (compare example B with examples C and D) and the more the wire resistance is increased.
[0054] As illustrated in FIG. 6 , the wires 32 a , 32 b have a far smaller width 40 a , 40 b as compared to the trench widths 36 a , 36 b , respectively, made available for wiring during patterning and etching. In fact, the wires 32 a , 32 b have a width 40 a , 40 b in the range of approximately ⅓-⅔ the widths 36 a , 36 b of the trenches 20 a , 20 b , respectively. Typically this would be considered undesirable because it tends to increase wire resistance. The present invention, however, is not concerned with wire resistance, and may be used in conjunction with devices that are not affected by wire resistance, such as ultra low power CMOS devices, wherein the power consumption is determined primarily by the transistor driver resistance and the wire capacitance. By reducing the size (e.g., height 42 and width 40 a , 40 b ) of the wires 32 a , 32 b , the capacitance of the device 10 can be reduced even further, (compare examples C and D of Table 1). Therefore, it is possible in the present invention to pattern and etch the trenches 20 a , 20 b having an aspect ratio of 2:1, but end up with much narrower conductive wires 32 a , 32 b within the trenches 20 a , 20 b having an aspect ratio of 5:1.
[0055] A dual damascene structure may also be formed in accordance with the present invention. As illustrated in FIG. 7 , a second wiring level 45 a may be formed on the first wiring level 44 , in this example comprising a dual damascene wiring structure. First, a capping layer 46 is deposited over the first metal wiring level 44 . The capping layer 46 may comprise SiCN, or other similarly used material. The capping layer 46 may be deposited using CVD, PECVD, etc., having a thickness in the range of approximately 5-100 nm, e.g., 20 nm. The purpose of the capping layer 46 is to prevent diffusion of copper from the conductive wire 32 a , 32 b formed in the first wiring level 44 into the dielectric layer 48 in the second wiring level 45 a . The capping layer 46 may also optionally be used as an etch stop layer during patterning and etching of the vias in the second wiring level 45 . Alternatively, the capping layer 46 could be replaced (not shown) by a selective conductive cap, such as electroless plated COWP; a damascene conductor, such as Ta; a dielectric, such as SiCN; or a substantially etched dielectric layer, as known in the art.
[0056] A second dielectric layer 48 is deposited over the capping layer 46 . The second dielectric layer 48 may comprise a dielectric material having a low dielectric constant (k), wherein “low k” is defined as a dielectric constant (k) below 3.0, or in the range of approximately 1.5-2.7, such as porous poly(areylene) ether (e.g., porous SiLK™ (Dow Chemical)), porous SiCOH, porous SiO 2 , teflon, amorphous carbon, etc. The second dielectric layer 48 may be deposited using CVD, PECVD, spin-on deposition, etc., to a thickness of approximately 100-3000 nm, e.g., 400 nm.
[0057] A hard mask 50 is then deposited over the second dielectric layer 48 . The hard mask 50 may comprise a dielectric material, such as SiC, SiCN, SiCOH, SiO 2 , Si 3 N 4 , etc. The hard mask 50 may be deposited using CVD, PECVD, etc., to a thickness of approximately 1-100 nm, e.g., 10 nm.
[0058] A photoresist 52 is then applied over the hard mask 50 , as illustrated in FIG. 7 . The photoresist 52 may be applied to a thickness in the range of approximately 50-3000 nm, e.g., 200 nm. The photoresist 52 may comprise a positive or negative photoresist 52 as desired. The photoresist 52 is then patterned and etched using standard BEOL exposure and RIE formation techniques to form trenches 54 a , 54 b ( FIG. 8 ). Narrower trenches 54 a may be formed having an aspect ratio of approximately 2:1, and a minimum trench width 56 a in the range of approximately 100-150 nm. Wider trenches 54 b may be formed having any width, and a wide range of aspect ratios, e.g., an aspect ratio of approximately 1:2, 1:10, etc. As described supra, the photoresist 52 may be completely consumed during the standard BEOL formation processing when used in conjunction with a p-SiLK second dielectric layer 48 . Alternatively, a multi-layer hard mask may be used (not shown), as described supra.
[0059] As illustrated in FIG. 9 , a conformal dielectric liner 58 is deposited over the surface of the device 10 . The liner 58 may comprise a dielectric material having a low dielectric constant (k), wherein “low k” is defined as a dielectric constant (k) preferably below 3.0, or in the range of approximately 1.4-4.5, such as SiCOH, SiO 2 , poly(areylene) ether (e.g., SiLK™ (Dow Chemical)), teflon, or other similarly used material. The liner 58 may be deposited using PECVD, CVD, or other similar deposition techniques. The liner 58 may have a thickness up to approximately ½ the width of the minimum trench width 22 a , and preferably ⅓ the width of the minimum trench width 22 a (100-150 nm), i.e., a thickness in the range of approximately 30-50 nm.
[0060] A photoresist layer 60 is then applied over the liner 58 , as illustrated in FIG. 10 . The photoresist 60 may be applied having a thickness in the range of approximately 50-3000 nm, e.g., 200 nm. The photoresist layer 60 over an optional anti-reflective layer (not shown) is then patterned using conventional positive or negative photolithography techniques, as illustrated in FIG. 11 . A plurality of vias 62 may then be etched.
[0061] The vias 62 may be formed having different widths as desired. For example, as illustrated in FIGS. 12-14 , narrower vias 62 a may be formed having a width 64 a approximately ⅓ the minimum trench width 56 a , e.g., in the range of approximately 30-50 nm. The narrower vias 62 a may be useful when forming devices having tighter device densities. Alternatively, wider vias 62 b may be formed having a width 64 b approximately the same size as the minimum trench width 56 a ), e.g., in the range of approximately 100-150 nm, as illustrated in FIGS. 15-17 .
[0062] To form either vias 62 a , 62 b , the photoresist layer 60 is patterned, as known in the art ( FIG. 11 ). Multiple etch chemistries are employed to then etch down through the conformal liner 58 , the hard mask 50 , the second dielectric layer 48 , and the capping layer 46 to get down to the first wiring level 44 ( FIGS. 12 and 15 ), using a RIE process as know in the art. The etching process may be performed until substantially all of the photoresist 60 is consumed.
[0063] As illustrated in FIG. 12 , when forming the narrower vias 62 a , the etch removes only a portion 72 of the liner 58 on the sidewalls 68 a of the trenches 54 a having the minimum trench width 56 a . In contrast, when forming the wider vias 62 b , the etch removes the conformal liner 58 on the sidewalls 68 b of the trenches 54 a having the minimum trench width 56 a ( FIG. 15 ).
[0064] Following via 62 a , 62 b formation, a cleaning process is performed and the metallization is deposited. As illustrated in FIGS. 13 and 16 , a conductive liner 74 , a seed layer 76 and a conductive layer 78 may be deposited as described supra in connection with the first wiring level 44 . Again, the conductive liner 74 and the seed layer 76 are not drawn to scale for purposes of illustration.
[0065] Following deposition of the metallization, (the conductive liner 74 , the seed layer 76 and the conductive layer 78 ), a planarization process is performed to remove the excess metallization on the surface of the second wiring level 45 a . A CMP or other similarly used process may be used to planarize the surface of the second wiring level 45 a . The planarization process is performed down to the conformal liner 58 , as illustrated in FIGS. 14 and 17 . Alternatively, the planarization process may be performed down to the hard mask 50 (not shown). Electrically conductive wires 80 a , 80 b are produced following planarization.
[0066] The method for forming the second wiring level 45 a , described supra, was for a trench first, via second dual damascene feature formation. Alternatively, a second wiring level 45 b may be formed using a via first, trench second dual damascene feature formation.
[0067] For example, following the formation of the device 10 illustrated in FIG. 7 , as described supra, including the capping layer 46 , the second dielectric layer 48 , the second hard mask 50 and the photoresist layer 52 , the photoresist layer 52 is patterned ( FIG. 18 ). The second dielectric layer 48 and the hard mask 50 are then etched using standard BEOL exposure and RIE formation techniques to form vias 100 , as illustrated in FIG. 19 . The vias 100 may be formed having an aspect ratio of approximately 2:1, and a width 102 in the range of approximately 100-150 nm. As described supra, the photoresist 52 may be completely consumed during the standard BEOL formation processing when used in conjunction with a p-SiLK second dielectric layer 48 . Alternatively, a multi-layer hard mask may be used (not shown), as described supra.
[0068] As illustrated in FIG. 20 , a conformal dielectric liner 104 is deposited over the surface of the device 10 . The liner 104 may comprise a dielectric material having a low dielectric constant (k), wherein “low k” is defined as a dielectric constant (k) preferably below 3.0, or in the range of approximately 1.4-4.5, such as SiCOH, SiO 2 , poly(areylene) ether (e.g., SiLK™ (Dow Chemical)), teflon, or other similarly used material. The liner 104 may be deposited using PECVD, CVD, or other similar deposition techniques. The liner 104 may have a thickness in the range of approximately 10-50 nm.
[0069] A gap filling organic anti-reflective coating (ARC) 106 is deposited over the surface of the device 10 filling the vias 100 , as illustrated in FIG. 21 . The ARC 106 may be deposited having a thickness in the range of approximately 100-300 nm, e.g., 200 nm, and may comprise organic or inorganic materials, such as polymers, spin-on glass, etc. The ARC 106 may be deposited using spin-on, CVD, or other similarly used methods. The ARC 106 provides a planar surface for further processing.
[0070] A third hard mask 108 is deposited over the ARC 106 using, a low temperature oxide deposited by PECVD at approximately 200° C. (so as not to damage the ARC 106 ), a spin-on oxide deposition with a low temperature cure (“low temperature” meaning a temperature below approximately 300° C.), etc. The third hard mask 108 may comprise a dielectric material, such as SiC, SiCN, SiCOH, SiO 2 , Si 3 N 4 , etc., and may be deposited to a thickness of approximately 1-100 nm, e.g., 10 nm.
[0071] A photoresist layer 110 is then applied over the third hard mask 108 , as illustrated in FIG. 21 . The photoresist 110 may be applied having a thickness in the range of approximately 5-3000 nm, e.g., 200 nm. An optional second ARC layer (not shown) may also be deposited over the photoresist layer 110 if desired. The photoresist layer 110 is then patterned using conventional positive or negative photolithography techniques, as illustrated in FIG. 22 .
[0072] Various etch chemistries are used to remove portions of the third hard mask 108 and the ARC 106 , as illustrated in FIG. 23 . A portion of the ARC 106 remains within the vias 100 to prevent damage to the conductive material within the wires 32 of the first wiring level 44 during the subsequent etching process. A different etch chemistry is used to remove the liner 104 and the remaining hard mask 108 , as illustrated in FIG. 24 . Another etch chemistry is used to remove a portion of the second dielectric layer 48 , thereby forming trenches 112 within the second wiring level 45 b , as illustrated in FIG. 25 . As described supra, trenches 112 a , 112 b having different widths 114 a , 114 b may be formed.
[0073] As illustrated in FIG. 26 , the remaining ARC 106 within the base of the vias 100 is removed using an ARC removal etch process. A conformal dielectric liner 116 is then deposited over the surface of the device 10 . The liner 116 may comprise dielectric material having a low dielectric constant (k), wherein “low k” is defined as a dielectric constant (k) preferably below 3.0, or in the range of approximately 1.4-4.5, such as SiCOH, SiO 2 , poly(areylene) ether (e.g., SiLK™ (Dow Chemical)), teflon, or other similarly used material. The liner 116 may be deposited using PECVD, CVD, or other similar deposition techniques. The liner 116 may have a thickness up to approximately ½ the width of the minimum trench width 114 a , and preferably ⅓ the width of the minimum trench width 114 a (100-150 nm), i.e., a thickness in the range of approximately 30-50 nm.
[0074] Multiple etch chemistries are employed to then etch down through the conformal liners 116 , 50 and the capping layer 46 within the base of the vias 100 to get down to the first wiring level 44 , as illustrated in FIG. 27 .
[0075] A cleaning process is then performed and the metallization is deposited, as described supra. As illustrated in FIG. 28 , a conductive liner 120 , a seed layer 122 and a conductive layer 124 may be deposited as described supra in connection with the first wiring level 44 . Again, the conductive liner 120 and the seed layer 122 are not drawn to scale for purposes of illustration.
[0076] Following deposition of the metallization, (the conductive liner 120 , the seed layer 122 and the conductive layer 124 ), a planarization process is performed to remove the excess metallization on the surface of the second wiring level 45 b , as illustrated in FIG. 29 . A CMP or other similarly used process may be used to planarize the surface of the second wiring level 45 b . Electrically conductive dual damascene wires 126 a , 126 b are produced following planarization. | A structure. The structure includes a substrate. A first dielectric layer is on and in direct mechanical contact with the substrate. A first hard mask is on the first dielectric layer. A first and second trench is within the first dielectric layer and the first hard mask. The second trench is wider than the first trench. A first conformal liner is on sidewalls of the first and second trenches. The first conformal liner is in direct physical contact with the substrate, the first dielectric layer, and the first hard mask A first conductive material that includes copper fills the first and second trenches. A planar surface of the first conductive material is coplanar with a top surface of the first conformal liner and a top surface of the first hard mask. | 7 |
BACKGROUND OF THE INVENTION
Known portable devices for warning drivers of temporary hazardous road conditions provide either a visual warning only, or if an attempted audible or mechanical warning device is provided it is of such a complicated and expensive structure that the cost tends to be prohibitive. Furthermore, such audible or mechanical road warning devices are subject to movement or "dancing" across the highway road surface during co-action with the vehicles and are therefore uncertain as to their placement retention on the road surface.
One example of a known warning device is that of a plurality of parallel, transversely extended mounds of bituminous or like material. This type of warning device has several disadvantages, however; one being the length of time of installation and or removal. Another is the permanent disfigurement of the road surface upon removal, requiring at times another process of repair in the nature of patching. Yet another is the fact that the bituminous material is then normally discarded.
SUMMARY OF THE INVENTION
The present invention relates to a portable apparatus for warning drivers of dangerous or hazardous road conditions ahead which comprises one or more elongated flat mats of resilient material, such as rubber or the like, each mat having a generally rectangular shape and having formed therein at least one set of transversely extended, equidistantly longitudinally spaced openings of identical size and shape. The width of each opening is such that when the mat is placed directly in front of a tire of a conventional highway vehicle, the tire, moving normal to the transverse extent of the openings or slots, sinks sequentially within the slots to set up an audible and mechnical rumbling of the vehicle to forewarn the driver. Each mat can be secured to the road by an adhesive, or by a plurality of anchor bolts inserted through the mat into the road, or by one or more resilient cable units threaded through the fore and aft portions of each mat and stretched across the road to be staked at each side of the road, or by any combination of these arrangements.
An advantage of the portable nature of the warning apparatus is that each mat can easily be removed when highway work is suspended, or when the temporary danger is removed, and again quickly replaced when necessary. Motorists are not lulled into an unconcerned attitude which often tends to result when warning signs and devices are left in place when not needed. For example, when motorists see signs and warnings of certain highway work and perils which they then fail to encounter as they proceed, this tends to erode their faith in such signs and warnings.
It is therefore an object of the present invention to provide an improved portable highway or road warning device.
It is another object of the present invention to provide a portable road warning device which effects both an audible and mechanical warning to a motorist as he or she drives over it.
Another object of this invention is to provide a portable road warning device which can be quickly removably secured in place on a road surface to forewarn oncoming motorists of road perils ahead.
Yet another object of this invention is to provide a portable road warning device having the aforementioned advantages which is economical to manufacture while being dependable and reliable in its use, having the capability of being used over and over again.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of one embodiment of the invention, and showing road attaching units in exploded view;
FIG. 2 is a perspective view of a second embodiment of the invention;
FIG. 3 is a plan view of a highway, broken into portions, with differing arrangements of the embodiments of the invention being illustrated;
FIG. 4 is an enlarged fragmentary view of a corner of the embodiment of FIG. 1;
FIG. 5 is an enlarged vertical sectional view taken along the line 5--5 in FIG. 4;
FIG. 6 is another vertical sectional view taken along the line 6--6 in FIG. 2;
FIG. 7 is a slightly reduced, broken vertical sectional view taken along the line 7--7 in FIG. 3; and
FIG. 8 is a vertical sectional view taken along the line 8--8 in FIG. 6.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of the invention is shown at 10 in FIG. 1, the portable warning or "rumble" apparatus comprising a substantially rectangular mat 11 of resilient material having a plurality of equidistantly spaced openings 12 formed therein, with the openings having their lengthwise dimension extended transverse to the width of the mat 11. The mat 11 has a solid periphery 13 about all four edges, and the openings 12, termed "slots" hereinafter, are uniform in shape and dimension and are formed parallel in a single row.
To ensure that an audible and mechnical rumbling of the vehicle results when one of its leading tires runs across the mat 11, the slots 12 each have a length of approximately forty (40) inches, with a width of approximately six (6) inches. It is noted the length and width of the slots 12 actually extend the width and length, respectively, of the mat 11. It has been ascertained that the tread width of an average, conventional over-the-road tractor-trailer tire striking the road surface is approximately 7-81/2 inches, thus the length of the slots 12 is ample to completely receive the tire tread as the tire moves normal to the set of slots 12, as seen in FIG. 3 where a pair of mats 11 have been placed side-by-side. This assumes the mat 11 is placed directly in line with the direction and path of movement of one of the leading tires of the vehicle, the vehicle traveling in its normal position centered in its lane.
The mats 11 of FIG. 3 are placed such that each mat is located to receive the leading tire of a conventional vehicle moving from left to right on the lower half or lane 14 of the highway road 16, the center stripe 17 separating the two opposite lanes 14 and 18 of opposing traffic. It of course follows that should both leading tires move across the mats 11, the trailing tires would also, assuming the vehicle stayed in the lane 14.
Each mat 11 has an outer dimension of approximately 4'×23 1/2', and a thickness of approximately 5/8". One mat actually used for experimental purposes by the inventors was a commercially available conveyor belting with the trade name Plylon manufactured and sold by Goodyear Tire & Rubber Company. It is believed that any resilient, possibly reinforced, material such as that would be of suitable composition and have suitable life for the intended purpose of the invention.
Each mat 11 is removably secured in place, as shown for example in FIG. 3, by a plurality of anchor bolt units 19 shown in FIGS. 1 and 3. Each unit 19 comprises an expandable sleeve 21 which is insertable into a properly sized hole 23 drilled into the road 16 material (concrete or bituminous conventionally); a washer 24 placed over a hole 22 formed in the peripheral edge 13 of the mat 11 and an anchor bolt 26 inserted through the mat hole 22 and further insertable into the sleeve 21 so as to expand the sleeve 21 into locking engagement with the walls 27 (FIG. 5) of the road material hole 23. Referring to FIG. 1, it will be noted mat holes 22 are formed in the corners and in the sides of the mat 11.
A modified mat apparatus 10' is shown in the center fragmented portion of FIG. 3, laid right down the centerline stripe 17 of the highway. Mat 11' is substantially identical to mat 11 except it is longer and can have holes 22 formed therein, or it may be held to the surface 28 (FIG. 7) of the road by an adhesive 25 of commercial availability for bonding rubber or the like to surfaces such as concrete or bituminous. A peel-off type backing (not shown) can be provided which would be removed only when the mat 11' was put into use. It should be realized that this arrangement provides for only one use of a mat 11'; however, in certain highway locations a more permanent centerline mat 11' may be preferable as a means of warning a motorist that he or she is riding on or moving across the center stripe 17. This arrangement thus warns a motorist against "drifting" out of his or her lane.
A second modification is the apparatus 10", shown particularly in FIGS. 2, 3, 6 and 8. The mat 29 has a width substantially the same as the entire width of the lane 14, is again generally rectangular with a solid peripheral edge 13 as with the mat 11, and rather than one row of equidistantly spaced, uniform openings or slots 30 formed parallel therein, has a pair of rows 31 and 32 of slots 12. The rows 31 and 32 are spaced laterally apart such that their longitudinal centerlines are located approximately in the path of the leading, front tires of an oncoming conventional highway vehicle. The length of each slot 30 may be slightly greater than that of the slots 12, as illustrated, however the criteria that the length again is sufficient to fully receive the full tread width of said vehicle, from a small car to the large over-the-highway tractor trailer-type truck, is followed.
The mat 29 is secured to the road surface by a pair of identical cable units 33 (FIGS. 2, 6 and 8). Each cable unit 33 comprises a cable 34 of a length to stretch completely across the highway 16, a coil spring 36 for connection at one end of the cable 34, and a pair of stakes 37 for securing the cable end and cable-spring end to the roadbed on each side of the highway 16.
To eliminate wear on each cable as much as possible, a flattened serpentine passage 38 is formed within and along the leading and trailing edges 39 and 41, respectively, of the mat 29. The depth of the open, upper and lower exposed portions (FIGS. 6 and 8) is such that under normal use, the cable exposed thereat will not be engaged with either a tire or the road surface 28. The cable 34 may be vulcanized in the mat 29 to prevent bunching up of the mat on the cable.
In actual tests, the embodiment 10" (FIG. 2) was held securely in place on a major highway for twenty-seven (27) straight days of use before one or more anchor bolt units, known otherwise as lag screws, worked loose. In another test, a quick drying epoxy was used in the anchor bolt holes 23, and at the end of twenty-five (25) days there was no evidence of loosening of the anchor bolts 26. The mat 11 can be quickly removed by withdrawing the anchor bolts 26 and washers 24, then inserting a shorter bolt (not shown) into the sleeve 21 to protect the hole 3 and sleeve 21 from filling with debris. Re-installation of the mat 11 can then be easily and quickly accomplished.
It is contemplated that a mat, such as 29, can be used in an emergency by merely being located in the path of oncoming vehicles as is shown in FIG. 3, without any initial securement to the highway. However, actual testing has shown that the mat tends occasionally to "dance" on the highway and to change its position when run over by one or more vehicles.
For that reason, securement of at least a temporary nature is recommended. The provision of the springs 36 at one end, or at both ends of the cables 34 near the stakes facilitates a retention of the mat 29 in its original position with the slots 30 transverse to the flow of traffic. When the mat 29 is no longer necessary, it is readily removed by withdrawing the stakes 37 and pulling the mat off the highway without significant inconvenience to traffic.
Another embodiment (not shown) is the provision of a single, elongated strip of belting material of the type referred to hereinbefore in connection with the mats 11 of the various embodiments illustrated. The strip could have, for example, the dimensions of a slot 12 of FIG. 1, and the thickness of the mat 11; or for example, it could extend completely across a lane, having a length of twelve (12) feet.
It could have a peel-off type backing to expose an adhesive material on the undersurface in the nature of the mat 11' and adhesive 25 of FIG. 7 and would be adhered to the highway as a permanent warning strip, placed transversely in single strip form or as a plurality of strips in the same manner as the slots 12 of FIG. 1. It is believed that this type of strip for audible and physical warning to the vehicle driver would outlast the comtemporary bituminous material presently being used.
Obviously, many other modifications and variations of the present invention are possible in light of the above teachings, for example all types of securement can be applied to all embodiments of the mats. It is therefore to be understood, that within the scope of the appended claims, this invention may be practiced otherwise than as specifically described. | A portable apparatus for warning drivers of temporary and/or hazardous road conditions ahead comprising a portable flat mat of resilient material which is either removably or permanently secured to the road surface in or near the path of an oncoming vehicle, and which has a plurality of equidistantly sapced slotted openings formed therein each of a size to completely, momentarily receive at least one of the front tires of the vehicle. When the said front or any other tire runs over said slotted openings, an audible and mechanical rumbling of the vehicle is set up thereby warning and physically alerting the driver of a road condition ahead which requires special attention. | 4 |
TECHNICAL FIELD
[0001] Embodiments of the present invention pertain to crystal oscillators, and in some embodiments, to processing systems such as wireless communication devices and other systems and devices that use a precision time reference.
BACKGROUND
[0002] Crystal oscillators and crystal-oscillator systems are used to provide a precision time reference for many applications, such as processing and computing systems including communication devices. Some conventional crystal-oscillator systems employ large resistors and/or capacitors for low-pass filtering as part of a feedback process to limit the amplitude of the oscillation frequency. One problem with these conventional crystal-oscillator systems is that the large resistors and capacitors usually require a large amount of circuit area on a die. Another problem with these large resistors and capacitors is that they are susceptible to process variations making it difficult to design and fabricate accurate oscillator circuits. Another problem with these conventional crystal-oscillator systems is that their output level may vary over time due to environmental factors.
[0003] Thus, there are needs for improved oscillators and methods.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The appended claims are directed to some of the various embodiments of the present invention. However, the detailed description presents a more complete understanding of embodiments of the present invention when considered in connection with the figures, wherein like reference numbers refer to similar items throughout the figures and:
[0005] [0005]FIG. 1 is a block diagram of a system in accordance with embodiments of the present invention;
[0006] [0006]FIG. 2 is a block diagram of an oscillator element in accordance with embodiments of the present invention;
[0007] [0007]FIG. 3 is a circuit diagram of an oscillator element in accordance with embodiments of the present invention; and
[0008] [0008]FIG. 4 is a flow chart of a precision time reference generating procedure in accordance with embodiments of the present invention.
DETAILED DESCRIPTION
[0009] The following description and the drawings illustrate specific embodiments of the invention sufficiently to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Examples merely typify possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in or substituted for those of others. The scope of embodiments of the invention encompasses the full ambit of the claims and all available equivalents of those claims.
[0010] [0010]FIG. 1 is a block diagram of a system in accordance with embodiments of the present invention. System 100 may be part of any computing or processing system including computer systems, server systems, and wireless communication devices and systems. System 100 includes oscillator system 102 to generate precision time reference 104 for use by system elements. System elements which use precision time reference 104 may include, for example, receiver/transmitter elements 106 , data-signal processing elements 108 , and other system elements 110 including phase-locked loops, displays and I/O devices. In some embodiments, elements 106 , 108 and/or 110 may be on-chip elements.
[0011] Oscillator system 102 may include oscillator element 112 to generate oscillation frequency 114 and a switching-frequency generator 120 to provide switching frequency 116 . Switching frequency 116 may be responsive to oscillation frequency 114 . In embodiments, switching frequency 116 may be a multiple of oscillation frequency 114 . Oscillator system 102 may also include buffer-amplifier element 118 which may instruct switching-frequency generator 120 to generate a multiple of the oscillation frequency when the oscillation frequency is determined to be stable. In some embodiments, the stability of the oscillator frequency may be determined based on a number of clock cycles (e.g., after power up). In other embodiments, the stability of the oscillator frequency may be determined by sampling energy of the oscillation frequency and setting a latch when the energy exceeds a predetermined threshold.
[0012] In embodiments, switching-frequency generator 120 may generate switching frequency 116 as a multiple of oscillation frequency 114 . Buffer-amplifier element 118 may receive oscillation frequency 114 and determine when the oscillation-frequency output is stable. In one embodiment, a system element, such as data-signal processing element 108 , may provide a control signal to switching-frequency generator 120 to tailor oscillation frequency 114 for individual circuit variances. For example, process variation may cause one chip to require a switching frequency of 1.000 MHz for minimum power consumption while another chip may require 1.001 MHz. In embodiments, processing element 108 may initially, continuously, and/or intermittently monitor the oscillation frequency and may adjust the switching frequency to reduce the oscillation amplitude to allow each chip to operate its oscillator at a minimum power level. In some embodiments, processing element 108 may adjust the switching frequency as a battery condition changes, or as the temperature changes to help keep the oscillator at an amplitude level which may minimize power consumption.
[0013] In embodiments, buffer-amplifier element 118 may perform signal buffering and amplification to generate precision time reference 104 comprising a square wave suitable for CMOS applications. In some embodiments, element 118 may have hysteresis for noise isolation. In some embodiments, element 118 may instruct switching-frequency generator 120 to vary the characteristics of the switching frequency to change or substantially maintain the level of the oscillation-frequency output, for example, to compensate for environmental changes affecting the oscillator. In embodiments, oscillation frequency 114 and precision timing reference 104 may be almost any predetermined frequency. For example, oscillation frequency 114 and precision timing reference 104 may be around 32 kHz (e.g., 32.768 kHz), around 13 MHz, or around 3.6 MHz (e.g., 3.686 MHz) and multiples thereof. The exact frequency may depend on the requirements of the system or system elements.
[0014] In embodiments, oscillator element 112 may include an oscillator sub-circuit to generate oscillation frequency 114 and an amplitude-limiter sub-circuit to provide feedback to the oscillator sub-circuit to control a level of oscillation frequency 114 . An example of an oscillator element is illustrated in FIG. 2. The amplitude-limiter sub-circuit may include a switched-capacitor network to control the feedback based on switching frequency 116 and the level of oscillation frequency 114 . In embodiments, switching elements of the switched-capacitor network may be switched in opposition when oscillation frequency 114 is stable. In some embodiments, characteristics of switching frequency 116 may be varied to change the level of oscillation frequency 114 . The characteristics of the switching frequency that may be varied include at least the switching rate/or the duty cycle. In embodiments, the oscillation frequency may be controlled by a ceramic, quartz or another piezoelectric type material which have either a crystalline or a non-crystalline structure.
[0015] In embodiments, system 100 may be a wireless communication device and may include receiver/transmitter elements 106 . In these embodiments, elements 106 may receive and/or transmit RF communications using antenna 122 . In these embodiments, system 100 may, for example, be a personal digital assistant (PDA), a laptop or portable computer with wireless communication capability, a web tablet, a wireless telephone, a wireless headset, a pager, an instant messaging device, an MP3 player, a digital camera, an access point, or other device that may receive and/or transmit information wirelessly. In these embodiments, elements 106 may receive and/or transmit RF communications in accordance with specific communication standards, such as the IEEE 802.11 (a), 802.11 (b) and/or 802.11 (g) standards for wireless local area network (LAN) standards, although elements 106 may receive and/or transmit communications in accordance with other techniques including Digital Video Broadcasting Terrestrial (DVB-T) broadcasting standard, and the High performance radio Local Area Network (HiperLAN) standard.
[0016] Antenna 122 may comprise a directional or omni-directional antenna including a dipole antenna, a monopole antenna, a loop antenna, a microstrip antenna or other type of antenna suitable for reception and/or transmission of RF signals. Elements 106 may provide convert RF signals to data signals for processing by data-signal processing elements 108 and for use by other elements 110 as part of the operation of system 100 . Data-signal processing elements 108 may also provide data signals to elements 106 for conversion to RF signals and transmission by antenna 122 .
[0017] Although system 100 is illustrated as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software configured elements, such as processing elements including digital signal processors (DSPs), and/or other hardware elements. For example, processing elements may comprise one or more microprocessors, DSPs, application specific integrated circuits (ASICs), and combinations of various hardware and logic circuitry for at least performing the functions described herein.
[0018] [0018]FIG. 2 is a block diagram of an oscillator element in accordance with embodiments of the present invention. Oscillator element 200 may be suitable for use as oscillator element 112 (FIG. 1) although other oscillation elements may also be suitable. Oscillation element 200 may include oscillator sub-circuit 202 to generate oscillation-frequency output 210 , and amplitude-limiter sub-circuit 204 to provide feedback to oscillator sub-circuit 202 to control and/or limit a level of oscillation-frequency output 210 . Oscillator element 200 may also include startup sub-circuit 206 to initially set bias of elements of oscillator sub-circuit 202 and/or amplitude-limiter sub-circuit 204 at power up.
[0019] In accordance with embodiments of the present invention, amplitude-limiter sub-circuit 204 includes switched-capacitor network 208 to help control the feedback to oscillator sub-circuit 202 based, at least in part, on switching-frequency input 212 and the level of oscillation-frequency output 210 . In embodiments, switching-frequency input 212 may be provided by a switching-frequency generator, such as switching-frequency generator 120 (FIG. 1).
[0020] [0020]FIG. 3 is a circuit diagram of an oscillator element in accordance with embodiments of the present invention. Oscillator element 300 may be suitable for use as oscillator element 200 (FIG. 2), although other circuits may also be suitable. Oscillator element 300 comprises oscillator sub-circuit 302 , amplitude-limiter sub-circuit 304 and startup sub-circuit 306 which may correspond respectively with oscillator sub-circuit 202 (FIG. 2), amplitude-limiter sub-circuit 204 (FIG. 2) and startup sub-circuit 206 (FIG. 2). Amplitude-limiter sub-circuit 304 includes switched-capacitor network 308 which may correspond with switched-capacitor network 208 (FIG. 2).
[0021] Oscillation sub-circuit 302 includes crystal 310 and transistor element 312 which may amplify and invert a voltage which may develop across crystal 310 . Element 312 may provide oscillation-frequency output 314 . Transistor element 316 may be a current source for element 312 , and may be a current mirroring element which mirrors current of transistor element 318 of amplitude-limiter sub-circuit 304 . Crystal 310 may comprise almost any ceramic, quartz or other piezoelectric-type material, and may have a crystalline or non-crystalline structure. In embodiments, crystal 310 may have a high “Q” mechanical resonance.
[0022] Amplitude-limiter sub-circuit 304 includes transistor elements 318 , 320 , 322 and 324 , which, along with switched-capacitor network 308 , may perform an amplitude-regulating function to limit and/or control the amplitude of the oscillation frequency at output 314 . Startup sub-circuit 306 may include transistor elements 326 , 328 and 330 and may initially provide a bias for elements 316 , 318 and 320 at power up. Switched-capacitor network 308 includes switching elements 332 and 334 along with capacitive elements 336 , 338 and 340 . In operation, switching element 332 may transfer charge from capacitive element 336 to capacitive element 338 , and switching element 334 may transfer charge from capacitive element 338 to capacitive element 340 . In embodiments, switching elements 332 and 334 may be alternatively switched (e.g., driven in opposition) by a switching frequency received at their inputs. The switching frequency may be a multiple of the oscillation frequency, and may be provided by switching-frequency generator 120 (FIG. 1). Initially, switching elements 332 and 334 may be closed to create a DC path between the inputs of elements 322 and 324 to help establish initial startup conditions.
[0023] The amount of charge provided to element 324 changes the bias of element 318 and the current through element 318 may be mirrored in element 316 . The current in element 316 may be proportional to the current through element 318 depending on the relationship of the sizes of the devices. In embodiments, element 316 may be a factor larger (e.g., 5×) than device 318 and may carry proportionally more current.
[0024] Before oscillation amplitude has grown large, elements 318 , 320 , 322 and 324 provide DC bias to supply element 312 with current. As the amplitude of the oscillation frequency at output 314 increases, element 312 drives an AC signal onto the input of element 322 . If the AC signal has a certain amplitude, element 322 may pull current proportional to the amplitude squared off of capacitive element 336 . This may cause a voltage on the input of element 324 to drop, reducing the current available to element 312 , reducing the AC amplitude until a static operating point is achieved.
[0025] Switching-capacitor network 308 may help reduce the semiconductor die area of element 300 while providing low-power amplitude limiting of the oscillation frequency. Although switching elements 332 and 334 are illustrated as specific-type transistor switching elements, this is not a requirement. In embodiments, switching elements 332 and 334 may be almost any switch or switching element, including, for example, a MEMS relay. In some embodiments, element 332 and element 334 may comprise transmission gates and may use both an NMOS and a PMOS device for better charge transfer. Capacitive elements 338 and 340 may be almost any size as their ratio and the switching frequency primarily may control the filter characteristics of network 308 .
[0026] When oscillator element 300 is first powered up, both element 332 and element 334 may be closed, creating a DC path between the inputs of element 322 and element 324 . The current source is biased which starts element 312 . When the oscillation becomes stable, element 332 and element 334 may be driven in opposition at a multiple of the oscillator frequency. Charge may then be transferred onto capacitive element 338 when element 332 is closed and element 334 open setting the voltage on capacitive element 338 to the voltage on capacitive element 336 . When element 332 opens and when element 334 closes, capacitive element 338 modifies the voltage on capacitive element 340 and the voltage on the input of element 324 . In this way, capacitive element 338 behaves as a resistor, and the value of resistance may be controlled by the frequency of switching of element 332 and element 334 . A reduction in semiconductor die area may be achieved over conventional low-pass filters with may use large resistances and capacitances. In embodiments of the present invention, capacitive element 338 is ratioed to capacitive element 340 and capacitive element 336 , and since process technology may control capacitance much better than resistance, an increase in precision may also be achieved.
[0027] In one embodiment, element 332 and element 334 are switched with the open and close times at a different duty cycle and/or switching rate than the primary frequency. In this way, a processor may control the switching and an adaptive algorithm may tailor the duty cycle and/or switching rate to accommodate environmental changes. Although circuit 300 is illustrated to include resistors and capacitors, one or more of such resistors and/or capacitors may be implemented with active devices, such as transistors, rather than with passive devices.
[0028] In one embodiment, the oscillation frequency may be provided at output 315 which is an input node for element 312 . Output 315 may be instead of or in addition to output 314 . In some cases, output 315 may provide a cleaner sinusoid signal for subsequent amplification than the sinusoid signal at output 314 . In this embodiment, output 315 may provide oscillation frequency 114 (FIG. 1) and may correspond with oscillation-frequency output 210 (FIG. 2).
[0029] In some embodiments, a switching element may be placed between the output of element 312 and the input of element 322 to disconnect amplitude limiter sub-circuit 304 from oscillator sub-circuit 302 until the oscillation has stabilized and the switching frequency 116 (FIG. 1) has been generated. When the oscillation is stable and switching frequency is available to amplitude limiter sub-circuit 304 , the switching element can be closed allowing amplitude limiter sub-circuit 304 to sample the level of oscillation.
[0030] [0030]FIG. 4 is a flow chart of a precision time reference generating procedure in accordance with embodiments of the present invention. Precision time reference generating procedure 400 may be performed by an oscillator system, such as oscillator system 102 (FIG. 1), although other systems may also be suitable for performing procedure 400 . Procedure 400 may be used for generating almost any precision time reference signal for use in almost any computing or processing system or device.
[0031] In operation 402 , a startup bias may be provided at power up to allow an oscillator to begin generating an oscillation frequency. Operation 402 may be performed by startup circuitry, such as startup sub-circuit 206 (FIG. 2). In operation 404 , an oscillation frequency is generated. Operation 404 may be performed by oscillator circuitry, such as oscillation sub-circuit 202 (FIG. 2).
[0032] In operation 406 , a switching frequency may be generated and provided to switching elements of a switched-capacitor network used as part of an amplitude limiting sub-circuit of an oscillation system. The switching frequency may be a multiple of the oscillation frequency and may be generated when the oscillation frequency is stable. Operation 406 may be performed by switching-frequency generator 120 (FIG. 1) and buffer-amplifier element 118 (FIG. 1) may determine when the oscillation frequency is stable.
[0033] In operation 408 , amplitude-limiting feedback may be generated to control or limit the amplitude of the oscillation frequency. The amplitude-limiting feedback may be generated by an amplitude limiter, such as amplitude-limiter sub-circuit 204 (FIG. 2) based on the switching frequency generated in operation 406 as well as the amplitude level of the oscillation frequency generated in operation 404 . Operations 404 , 406 and 408 may be performed substantially concurrently to generate a precision time reference.
[0034] In some embodiments, operation 410 may be performed. In operation 410 , the characteristics, such as the duty cycle and/or switching rate, of the switching frequency may be varied to change the level of the oscillation-frequency output. Operation 410 may be performed, for example, by buffer-amplifier element 118 (FIG. 1). Although the individual operations of procedure 400 are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently and nothing requires that the operations be performed in the order illustrated.
[0035] It is emphasized that the Abstract is provided to comply with 37 C.F.R. Section 1.72(b) requiring an abstract that will allow the reader to ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to limit or interpret the scope or meaning of the claims.
[0036] In the foregoing detailed description, various features are occasionally grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the subject matter require more features that are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment. | Briefly, in accordance with embodiments of the invention, switched capacitors may be utilized to emulate resistors in a longer time constant feedback network for amplitude regulation of a crystal oscillator. | 7 |
REFERENCE TO RELATED PATENT APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/630,165, filed on Nov. 22, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to automated devices for drying clothing and laundry. More specifically, the ambient air clothes dryer is a clothes dryer devoid of any dedicated heating elements or systems for heating the air.
[0004] 2. Description of the Related Art
[0005] The development of the automatic clothes dryer has been a great labor saving device for most households and, along with the automatic washing machine, has served to facilitate the commercial laundry industry as well. Automatic clothes dryers were initially developed when energy costs were relatively low, and accordingly make use of gas or electrical heat to accelerate the drying process. As a byproduct of the heat developed, the home or other structure is also heated, even though most of the heat is ducted to the exterior of the structure during dryer operation. Still, the residual heat output into the structure was not considered to be particularly undesirable, even in warmer conditions, as the energy costs required to operate air conditioning systems were much lower in the past.
[0006] However, with ever-increasing energy costs, the cost of operation of such conventional dryers has climbed considerably over the years, and even more so when the energy required to dissipate their heat output is considered. While conventional hot air clothes dryers have their place in very damp and/or cool climates, the heat they develop is an undesirable side effect of the drying operation in many parts of the country during much of the year. The alternative of the conventional clothes line is not suitable for many households due to the frequency of damp weather in many areas and seasons, and the time and labor required to tediously pin up each garment or article to the line and remove them, perhaps several hours later, when they are dry.
[0007] While some clothes dryers have been developed in the past that do not provide a source of heat during the drying operation, such dryers have not been found entirely satisfactory. Thus, an ambient air clothes dryer solving the aforementioned problems is desired.
SUMMARY OF THE INVENTION
[0008] The ambient air clothes dryer is an automated device including a motor-powered rotating drum having a fan providing axial airflow through the drum. No dedicated heating element is provided. Some embodiments include a fan motor and an additional motor to rotate the drum, while other embodiments utilize a belt or other drive from the fan output shaft to drive a jackshaft to rotate the drum, thereby saving weight, complexity, and energy. Yet another embodiment may be devoid of any fan or air circulation device, and may include only a motor to rotate the drum. This embodiment includes means for the removable and temporary installation of a conventional “box fan” therewith, to provide the air circulation required. Any or all of the embodiments may include a timer and/or humidity detector to provide for automatic shutoff of the fan and drum when the laundry is dry and/or a predetermined time has been reached.
[0009] The portability of the device allows it to be used indoors or outdoors, as desired. The device may take advantage of ambient heating sources within the home or other structure if so desired, e.g., a heat register, radiator, Franklin stove, etc., to provide some heating of the air, which then passes through the dryer drum. This also provides the beneficial effect of humidifying the air within the structure in colder weather. The device may be constructed to utilize twelve-volt power, if so desired, for use in camping when an automotive electrical system is available.
[0010] These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a partially broken away perspective view of a first embodiment of an ambient air clothes dryer according to the present invention, showing various details thereof.
[0012] FIG. 2 is a simplified side elevation view of an alternative embodiment of the present dryer, illustrating an alternative drum drive system.
[0013] FIG. 3 is another simplified side elevation view showing another alternative embodiment of a drum drive system.
[0014] FIG. 4 is an exploded perspective view of yet another alternative embodiment of the present dryer, in which a separate portable box fan is used to provide airflow through the drum.
[0015] FIG. 5 is a simplified schematic diagram of an exemplary electrical and control system that may be incorporated with the present dryer.
[0016] Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] The present invention comprises various embodiments of an ambient air clothes or laundry dryer, in which unheated air at ambient temperature is blown through the dryer drum to dry clothing therein. While some slight amount of heat may be provided from the fan motor, the present ambient air dryer device does not include any form of dedicated, specific heating apparatus, as is found in conventional clothes dryers.
[0018] FIG. 1 of the drawings illustrates a first embodiment of the present dryer 10 , in which a separate fan motor 12 and drum rotation motor 14 are employed. The dryer 10 includes a housing or shell 16 having a hollow dryer drum 18 therein. The drum 18 rotates within the housing 16 , and is supported by drum support wheels 20 or other mechanism installed internally within the housing 16 . The dryer drum 18 has an impervious, generally cylindrical wall 22 having a diameter D. A screened airflow inlet end 24 is positioned adjacent the fan motor 12 with its fan 26 and fan drive shaft 28 , with a screened airflow outlet end door 30 located opposite the inlet end 24 of the drum 18 . The two screened ends 24 and 30 are preferably of a sufficiently fine mesh or gauge as to preclude the passage of small articles (e.g., loose change, buttons, etc.) therethrough, and have diameters closely approaching the diameter D of the dryer drum 18 . The screen of the outlet door 30 may have a mesh or gauge sufficiently fine to serve as a lint trap for the dryer.
[0019] The fan drive motor 12 with its fan drive shaft 28 and circular, rotary fan 26 are concentrically disposed externally to the airflow inlet end 24 of the dryer drum 18 , but within the housing 16 . The fan 26 preferably has a diameter closely approaching the diameter D of the dryer drum 18 and the inlet and outlet ends 24 and 30 of the drum 18 , in order to maximize airflow through the drum 18 . A fan guard 32 is preferably installed across the air inlet opening of the dryer housing 16 , with at least the blades of the fan 26 being captured between the guard 32 and the screened inlet opening 24 of the drum 18 .
[0020] The separate drum drive motor 14 of the embodiment 10 of FIG. 1 drives an output shaft 34 , which in turn causes the drum 18 to rotate when the drum drive motor 14 is in operation. A common switch may be used to simultaneously actuate and deactivate the fan motor 12 and drum drive motor 14 , if so desired. In the case of the embodiment 10 of FIG. 1 , the output shaft 34 has a drum belt pulley 36 at its distal end, with a drum drive belt 38 extending around the pulley 36 and around a circumferential groove 40 in the dryer drum 18 .
[0021] The configuration of the ambient air clothes dryer 10 , as well as the configurations of other embodiments disclosed herein, requires no heavy, stiff high voltage and/or high amperage electrical cable, as is universally required for the heating elements of conventional electric clothes dryers. Moreover, no gas line connection is required, as there is no use of a gas heater for the incoming air of the present dryer. Thus, the present dryer is relatively lightweight in comparison to conventional dryers with their heating systems, and requires no more power than is capable of being supplied by a conventional household electric cord. (In some embodiments, the motor(s) may be 12-volt DC, enabling them to be powered from a motor vehicle electrical system if so desired.) The light weight and simple power requirements of the present ambient air dryer allow it to be moved about readily to various locations as desired. Accordingly, external transport wheels 42 may be provided beneath one or both ends of the housing 16 , with a pair of support legs 44 being shown beneath the opposite end of the housing 16 in the embodiment of FIG. 1 . A handle 46 may be provided across one side of the housing shell 16 , to facilitate lifting of that side for rolling the device 10 as desired by means of the wheels 42 .
[0022] FIG. 2 provides a side elevation view of an alternative drum drive system, in which the fan drive is also used to rotate the drum. In FIG. 2 , the fan motor 112 drives an output shaft 128 to which the fan 126 is connected, as in the corresponding components 12 , 28 , and 26 of the embodiment 10 of FIG. 1 . However, the fan motor output shaft 128 may include a drive belt pulley 129 thereon, with a jackshaft drive belt 131 extending from the fan motor shaft pulley 129 to a driven pulley 133 on a radially offset jackshaft or drum drive shaft 134 . The shaft 134 includes a drum drive belt pulley 136 at its distal end, with a drum drive belt 138 extending around the pulley 136 and riding in a circumferential groove 140 around the dryer drum 118 . It will be seen that the dryer drum 118 and drum drive belt 138 may be identical to the corresponding components 18 and 38 illustrated in FIG. 1 and described further above. The distinction between the configuration of FIG. 1 and that of FIG. 2 is the use of a shaft and belt system driven from the concentric fan motor to rotate the dryer drum in the embodiment of FIG. 2 .
[0023] FIG. 3 provides a side elevation view of an embodiment similar to that of FIG. 2 , differing in the means used to impart rotary motion directly to the drum. In FIG. 3 , the fan motor 212 drives an output or fan drive shaft 228 and fan 226 , with the shaft 228 having a drive belt pulley 229 thereon, just as in the case of the equivalent components 112 , 128 , 126 , and 129 of the embodiment of FIG. 2 . The pulley 229 , in turn, drives a jackshaft or drum drive shaft 234 by means of a jackshaft driven pulley 233 on one end of the shaft 234 , just as in the embodiment of FIG. 2 . However, rather than driving the drum 218 by means of a belt extending around the drum, as shown in FIGS. 1 and 2 , the jackshaft or drum drive shaft 234 has a friction wheel 236 (rubber-coated, etc.) at its distal end which bears against a circumferential friction band 238 surrounding the dryer drum 218 . Rotation of the friction wheel 236 imparts rotational motion to the dryer drum 218 by means of the friction between the wheel 236 and friction band 238 around the drum. It will be seen that such a drum drive system may also be incorporated in the embodiment of FIG. 1 , with the drum drive shaft 34 having a friction wheel 236 at the distal end thereof in lieu of the pulley 36 shown, and the dryer 10 incorporating the drum 218 of FIG. 3 with its friction band 238 .
[0024] FIG. 4 provides an illustration of an additional embodiment of the present ambient air dryer, in which a portable fan is used to supply the air through the dryer drum. The dryer 310 of FIG. 4 includes a housing 316 which contains the drum 18 and drum drive mechanism comprising motor 14 , drum drive shaft 34 , shaft output pulley 36 , and drum drive belt 38 , just as in the embodiment illustrated fully in FIG. 1 . However, rather than incorporating a fan integrally therewith, as in the embodiments of FIGS. 1 through 3 , the housing 316 of the dryer 310 includes a fan receptacle 317 in the rear wall thereof, i.e., adjacent the screened air inlet end 24 of the drum. The fan receptacle 317 is configured to fit a conventional portable fan F, commonly known as a “box fan,” therein. The fan receptacle 317 may be configured to accept other types of fans, as desired. A suitable electrical outlet 319 may be provided on the housing 316 , allowing the fan F to be plugged in for operation. Power to the outlet 319 may be provided through appropriate control circuitry on or in the dryer housing or cabinet 316 , as desired, to provide control of the fan F from the ambient air dryer controls.
[0025] FIG. 5 provides a basic electrical schematic diagram of circuitry that may be incorporated with the present ambient air clothes dryer in its various embodiments. In FIG. 5 , a conventional electrical power source 410 , e.g., 115-volt ac power from the power grid, or perhaps 12-volt dc power from an automotive or other electrical source when the ambient air dryer is manufactured to accept such power, provides electrical power to the dryer through a master switch 412 . The master switch provides power to the fan motor, e.g., motor 12 of FIG. 1 , and the drum drive motor, e.g., motor 14 of FIG. 1 , through a solenoid or other appropriate switch 414 . The switch 414 may incorporate the electrical outlet 319 for incorporation in the portable fan embodiment of FIG. 3 , if so desired.
[0026] The solenoid switch 414 is not required in the simplest embodiments of the present ambient air dryer. However, the dryer in any of its embodiments may include a timer and/or humidity sensor 416 , if so desired. These components are conventional in clothes and laundry dryers, and need not be described in detail herein. The timer may be incorporated in combination with a rotary on/off switch to serve the function of the master switch 412 , if so desired. In any event, the timer and/or humidity sensor 416 is normally closed when electrical power is applied for operation of the dryer, with the electrical contacts opening when a predetermined time is reached (for the timer) or when the air flow from the dryer reaches a predetermined low level of humidity (for the humidity sensor). If either of these conditions occurs, power to the solenoid switch 414 is interrupted, thereby interrupting power to the fan and drum drive motors 12 and 14 and shutting off the dryer. The opening of the solenoid switch 414 may also trigger the operation of a buzzer, bell, or other audible or visual signaling means to alert the user of the dryer that the drying operation is complete, much as in the case of conventional clothes dryers. Where the circuit of FIG. 5 is incorporated with the portable fan embodiment of FIG. 4 , the switch 414 may control power to the outlet 319 to shut off power to the outlet 319 , thereby shutting off the fan F plugged into the outlet 319 .
[0027] In conclusion, the present ambient air laundry and clothes dryer in its various embodiments provides a significant advance in efficiency for such machines, particularly in relatively warm and/or dry environments where the device may take advantage of the ambient air conditions.
[0028] It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. | The ambient air clothes dryer is an automated device providing axial flow of unheated ambient air through the dryer drum. The dryer may include different drum drive systems, timer and/or humidity detector controls, and a configuration utilizing a separate, portable fan for temporary, removable installation with the dryer housing to provide airflow through the drum. The ambient air dryer greatly reduces energy requirements for drying laundry when compared to conventional heated air dryers, and is quite effective in warm and/or dry climates. The ambient air dryer is portable and may be used indoors or outdoors. The device may be configured to use twelve-volt power from a motor vehicle for use in camping. When used indoors, the device may be placed with a heat source (heat register, etc.) to draw warm air through the drum while humidifying the air as it passes through damp laundry in the drum. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
An improvement upon applicant's WARNING LIGHT ASSEMBLY (U.S. Pat. No. 3,968,358).
BACKGROUND OF THE INVENTION
1. Field of the Invention:
School bus warning lights, particlarly a unitary assembly or fitting for economically and reliably performing in accordance with SAE standards for vibration, moisture, dust, corrosion and photometric alignment.
2. Description of the Prior Art:
Baader, U.S. Pat. No. 3,968,358;
Beaubien, U.S. Pat. No. 2,852,758;
Falge, U.S. Pat. No. 2,979,603;
Woodcook, U.S. Pat. No. 3,025,390;
Worden, U.S. Pat. No. 3,105,642;
Worden, U.S. Pat. No. 3,177,356;
Pawloski, U.S. Pat. No. 3,280,323;
Magi, U.S. Pat. No. 3,651,321.
Applicant's improvement consists in an improved annular body adapted as a fitting for supporting the combination of a lens cover superstructure and the sealed beam bulb assembly.
SUMMARY OF THE INVENTION
Applicant's fitting for vehicular warning lamps comprises an annular body defining on its top a circular rim adapted for supporting a lens cover superstructure and defining at its bottom a circular flange for supporting a general purpose seal beam light or lamp. The top circular rim includes a plurality of individual integrally formed tabs, each tab comprising an elongated shaft extending substantially normally away from the circular rim and with an inwardly directed projection surface on the distal end of the elongated shaft for complemental engagement with an annular retaining flange of the seal beam lamp.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a hooded dual warning light assembly, embodying two plastic fittings for warning lamps, according to the present invention.
FIG. 2 is a top plan of the plastic fitting.
FIG. 3 is a side elevation.
FIG. 4 is a bottom plan.
FIG. 5 is a side elevation, partially in section, showing the lens fitting with an outwardly and diametrically extending support strap or radius 40.
FIG. 6 is a top plan of a lens sealing gasket.
FIG. 7 is a vertical section, taken along section line 7--7 of FIG. 2.
FIG. 8 is a transverse section, taken along section line 8--8 of FIG. 2.
FIG. 9 is a side elevation, partially in section of a modified lens fitting. eliminating the diametrically extending strap 40.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, twin hood 10 is illustrated as supporting school bus warning lamps 12 and 14.
In FIGS. 2 and 5, applicant's lens fitting is illustrated as a one-piece black UV polycarbonate plastic housing defined as a cup-shaped body 16 having a symmetrical concave inner surface 18 which terminates at a rim generally indicated at 20. The seating plane 78 of lamp 64 is substantially the same diameter as the bottom circular flange 38 so that a gasket 62 is locally compressed. A plurality of integrally formed tabs 32, 34 and 36 each include a shank and an angled shoulder 58 with inner angle 60. Surface 80 extends radially inwardly and is adapted through its inclined configuration to position itself upon annular bulb retaining flange 72, regardless of slight manufacturing tolerances. The elongated shank of tabs 32, 34 and 36 are positioned at a diameter greater than the maximum possible bulb seal diameter, so as to accommodate the seal configuration of various bulb manufacturers. Gasket 62 extends inwardly over concave inner surface 18, and serves both as the seal between inner surface 18 and the lens cover (not illustrated) and a retainer for bulb-retaining flange 72 which is resiliently urged against the angled shoulder of the plastic tabs 32, 34 and 36.
As is apparent in FIGS. 5 and 9, when gasket 62, 62' are not present, lamp 64 will seat directly upon cap-shaped body 16, being resiliently urged thereagainst by contact with the resilient tabs 32, 32' 34 and 36. As a result, while gasket 62 is advantgeously employed within the total assembly, the misalignment of gasket 62 and/or its omission, does not defeat the support of the lamp 64 within the housing having outer rim 20, 20'.
As will be apparent in FIG. 2, the arrangement includes aligning bosses 92, 94, 96, and 98. Metallic screws (not illustrated) extend through the lens cover as well as through these bosses exteriors 48, 52, 50 and 46 as at 56 for fastening by conventional lock nuts, or the like.
Conical shaped bosses 24, 26, 28 and 30 are maintained in a series of identical tabs 84, 86, 88 and 90 such that the lamp cover may be secured to the housing by conventional stove bolts and the like extending into the identical tabs 84, 86, 88, and 90. Each tab contains a threaded aperture 22 for engagement with such stove bolts, or the like.
As illustrated in FIGS. 3 and 5, top rim 20 includes an inner radially inwardly inclined edge 21.
As illustrated in FIG. 8, rim 20 may include an inner shoulder 82 for support of the edges of the gasket 62 having aligning apertures 70, 73, and 74. Similar support surfaces are provided for bosses 92, 94, 96, 98. As illustrated in FIG. 3, the underside of shaped body 16 may include a series of elevated seats 48 for securement of the stove bolts extending through the lamp cover.
In FIG. 5, lamp 64 is shown as including an outer cover 71 and bulbs 66 and 68 protected by a rearwardly and diametrically extending strap radius 40. Strap 40 is eliminated in the modification shown in FIG. 9.
In FIG. 9, bulb 64 is supported means of the tab inclined shoulders 58' as well as the abutment of the bulb retaining flange 72' with a modified inner rim 76 having inwardly and radially extending shoulder 77 with inclined surface 80 engaging the curvate surface of the bulb exterior.
As will apparent, applicant's structure provides a lens fitting with all of the durability, alignment and sealing functions of WARNING LIGHT ASSEMBLY disclosed in his earlier U.S. Pat. No. 3,968,358. However, these functions are performed with a more economically manufactured fitting structure which facilitates testing of the bulb and bulb removal due to the open back configurations, as disclosed in FIGS. 2 and 9. | School bus warning light systems. Particularly an improved one-piece plastic fitting for supporting the sealed beam bulb in accordance with SAE photometric and durability standards. The fitting is characterized by its simplicity and ruggedness for securing and positioning the sealed beam bulb. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a process for producing polyesters from terephthalic acid and an alkylene glycol and more particularly a process for producing polyethylene terephthalate from terephthalic acid and ethylene glycol.
Heretofore, polyethylene terephthalate has been generally produced by an ester interchange process which passes through bis-(β-hydroxyethyl) terephthalate from dimethyl terephthalate and ethylene glycol and by a direct process which passes through bis-(β-hydroxyethyl) terephthalate directly from terephthalic acid and ethylene glycol.
The ester interchange process which uses dimethyl terephthalate as a starting material has advantages that dimethyl terephthalate has a relatively low melting point and is easily soluble and therefore dimethyl terephthalate and ethylene glycol react uniformly and bis-(β-hydroxyethyl) terephthalate, which is an intermediate of polyethylene terephthalate, can be easily obtained and that impurities contained in terephthalic acid are removed in the step for producing dimethyl terephthalate. This process needs an extra step for esterifying terephthalic acid with methyl alcohol to produce dimethyl terephthalate and further it is necessary to remove methyl alcohol by-produced in the ester interchange step. Consequently, this process has not been fully satisfactory from the viewpoints of apparatus and operation efficiency.
On the other hand, the direct process is superior theoretically to the ester interchange process but it has various problems in practice. Namely, terephthalic acid is not soluble in ethylene glycol and is generally low in apparent density and consequently it is difficult for terephthalic acid to be homogeneously dispersed in or mixed with an amount of ethylene glycol theoretically required for the esterification. In addition, sidereaction products, such as diethylene glycol produced by an etherification reaction of ethylene glycol during the esterification reaction are formed and the qualities of fibers or films manufactured from the resulting polyethylene terephthalate are considerably degraded.
In order to obviate such defects in the direct esterification process, a large number of proposals have already been made. For example, U.S. Pat. Nos. 3,442,868, 3,496,220, 3,590,072, 3,655,729, 3,781,213, 3,819,585 and 3,849,379 illustrate various process improvements in the direct esterification route of preparing linear polyesters. However, the most pertinent prior art is believed to be U.S. Pat. No. 3,689,461 which discloses an improved process that features direct esterification of a flowable uniform dispersion comprised of a paste of a polycarboxylic acid and a polyol with which has been admixed a prepolymerized product of like reactants. The product of this esterification is then further esterified and polycondensed to obtain a polyester of desired molecular weight.
Although the process of U.S. Pat. No. 3,689,461 has met with considerable commercial success, research in this field has been continued in an effort to improve upon this patented process. In particular, research efforts have centered on development of a process to provide an improved polyester that is more uniform than prior art products. Desirably, said relatively uniform polyester should have high molecular weight, be relatively free of ether linkages, have a low content of chloroform-soluble materials and a relatively narrow molecular weight distribution as estimated from the weight average molecular weight M w as compared with the number average molecular weight M n . It is well known in this art that polymer uniformity is important in production of high quality yarn. It is also known that a comparison of M w and M n is desirable because the weight average is particularly sensitive to the presence of larger species, whereas the number average is sensitive to the proportion by weight of smaller molecules.
SUMMARY OF THE INVENTION
Therefore, it is a prime object of this invention to provide an improved process for the direct esterification of terephthalic acid with an alkylene glycol.
Another object of this invention is to provide an improved process for directly preparing polyesters having improved uniformity, which polyesters can be conveniently processed into fibers, filaments, films and other shaped articles as a continuous or discontinuous process.
Another object is to provide a more economical process than heretofore and one which is capable of being operated continuously over an indefinite period of time.
Still another object is to provide an improved process wherein the formation of objectionable ethers such as diethylene glycol is inhibited during the esterification reaction, even in the absence of added ether inhibitors.
These and other objects are accomplished in accordance with this invention by a process which may be summarized as follows:
In a process for the preparation of high molecular weight linear polyesters of terephthalic acid which comprises partially esterifying terephthalic acid with an alkylene glycol containing 2 to 10 carbon atoms per molecule under direct esterification conditions and then further esterifying and polycondensing the partially esterified product until there is obtained a polyester of the desired molecular weight, the improvement which comprises:
(a) continuously subjecting to conditions of direct esterification at a temperature of 260°-300° C. and a pressure of 100-150 psig. a flowable, uniform dispersion comprised of (1) a paste consisting of said terephthalic acid, about 1.0 to 1.2 mols of said alkylene glycol per mol of terephthalic acid, and about 0.4 to 1.8 mols of water per mol of terephthalic acid, and (2) about 20 to about 40 parts by weight per part of paste of a partially esterified product of said terephthalic acid with said alkylene glycol, said partially esterified product having a reacted glycol to terephthalic acid mol ratio between 0.9 and 1.2 and a carboxyl conversion of about 70 to 80 percent, said partially esterified product being continuously recycled to the esterification zone at a temperature of 260°-300° C. and a pressure of 100-150 psig. and said paste being continuously added thereto at a predetermined point in the recycle system;
(b) continuously withdrawing a portion of the partially esterified product from step (a) equivalent to the terephthalic acid added in step (a), and continuously reacting said portion of the partially esterified product with about 0.5 to 0.7 mol of said alkylene glycol per mol of terephthalic acid added in step (a), said reaction being carried out at a temperature of 260°-300° C. and a pressure of 70-120 psig, thereby producing an esterified product having a reacted glycol to terephthalic acid mol ratio between 1.4 and 1.8 and a carboxyl conversion of about 90 to 95 percent;
(c) continuously further esterifying the esterification product of step (b) at a temperature of 260°-300° C. and a pressure of 300 to 400 mm of Hg to produce an esterified product having a reacted glycol to terephthalic acid mol ratio between 1.1 and 1.2 and a carboxyl conversion of 96 to 99 percent; and
(d) further esterifying and polycondensing the esterification product of step (c) at a temperature of 260°-300° C. and a pressure less than 300 mm Hg until there is obtained an improved polyester of the desired molecular weight.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In prior art processes for preparation of polyesters, such as that of U.S. Pat. No. 3,689,461, efficiency of esterification has been measured in terms of carboxyl conversion. However, we have found that the reacted glycol to terephthalic acid mol ratio is just as critical, if not more so, in describing esterification efficiency and in determining polymer properties. Optimum results are obtained by correlating the carboxyl conversion with the reacted glycol to terephthalic acid mol ratio in each esterification step of the process. Results indicate that as glycol to terephthalic acid mol ratio decreases the mol fraction of di-COOH ended species increases, even at constant conversion. Accordingly, a relatively high reacted glycol to terephthalic acid mol ratio is necessary in the present process, especially in the esterification steps of the overall process. The close relationship between reacted glycol ratio and molecular weight distribution in the polymer is particularly important in production of improved fiber.
In accordance with the preferred process of this invention, terephthalic acid is continuously fed to a mixer together with about 1.1 to 1.2 mols of ethylene glycol per mol of terephthalic acid and about 1.1 to 1.8 mols of water per mol of terephthalic acid. Optionally, a catalyst (esterification and/or polycondensation) is added to the mixture. In the mixer, agitation is performed whereby the terephthalic acid, ethylene glycol, water and catalyst are converted to a paste. The paste mixture is then pumped from the mixer by a feed pump to the inlet of a circulating pump where the paste mixture is combined with about 30 to 40 parts by weight per part of paste of recirculating or recycle partially esterified product described hereinafter. The resulting mixture is pumped by the circulating pump through a heater, for example, a multiple tube heat exchanger. Effluent from the heater passes to a first reaction zone, for example, a reactor-separator, for vapor-liquid separation and esterification at a pressure of about 120 to 130 psig and a temperature of 260°-280° C. Part of esterified effluent having a reacted glycol to terephthalic acid mol ratio between 0.9 and 1.1 and a carboxyl conversion of about 70 to 75 percent is returned to the inlet of the circulating pump where it is combined with fresh paste.
The remainder of the effluent from the first reaction zone, equivalent to the terephthalic acid added to the process in the paste, is metered to a second reaction zone together with about 0.5 to 0.7 mol of ethylene glycol per mol of terephthalic acid added in said paste. In the second reaction zone, for example, a reactor-separator, further esterification and vapor-liquid separation takes place at a pressure of 90 to 100 psig and a temperature of 270° to 280° C., thereby producing an esterified product having a reacted glycol to terephthalic acid mol ratio between 1.4 and 1.6, and a carboxyl conversion of 90 to 95 percent.
The effluent from the second reaction zone is transferred to a third reaction zone, for example, a reactor-separator, for further esterification and vapor-liquid separation at a pressure of 300 to 400 mm Hg and a temperature of 270°-280° C., thereby producing an esterified product having a reacted glycol to terephthalic acid mol ratio between 1.1 and 1.2 and a carboxyl conversion of 97 to 99 percent.
The effluent from the third reaction zone is preferably processed through three stages of polycondensation at a temperature of 270°-300° C. and a pressure less than 300 mm Hg, desirably 0.5 to 100 mm Hg, until there is obtained an improved polyethylene terephthalate having an intrinsic viscosity suitable for the production of tire yarn.
The following examples illustrate technical advantages of the present invention. All parts and percentages are by weight unless otherwise indicated.
EXAMPLE 1
About 41.5 parts per hour of purified terephthalic acid, 18.1 parts per hour of ethylene glycol, 7.3 parts per hour of water, 0.06 part per hour of antimony acetate, and 0.08 part per hour of diisopropylamine are continuously fed to a paddle wheel mixer where they are converted to a paste. The paste mixture at ambient temperature is then pumped from the mixer by a feed pump to the inlet of a circulating pump where it is combined with 40 parts per part of paste of recirculating or recycle, partially esterified product described hereinafter. The resulting mixture is pumped by the circulating pump through a multiple tube and shell heat exchanger where it is heated to about 275° C. After leaving the heat exchanger, the mixture enters a first reactor-separator for vapor-liquid separation and esterification. This reactor-separator is maintained at about 275° C. by conventional heating means, and about 125 psig pressure by means of an automatic vent valve. Residence time in the reactor is about 0.5 hour. The partially esterified product has a reacted glycol to terephthalic acid mol ratio of 1.0 and a carboxyl conversion of 70 percent.
The reaction mixture leaving the first reactor-separator is split, with part returned to the inlet of the circulating pump where it is combined with fresh paste and part (equivalent to the terephthalic acid added to the process in the paste) is metered to a second reactor-separator via a pipeline into which is injected 0.6 mol of ethylene glycol per mol of terephthalic acid added in said paste. In the second reactor-separator, further esterification and vapor-liquid separation takes place at a pressure of 100 psig and a temperature of 275° C. Residence time in this reactor is 0.5-1 hour. The product has a reacted glycol to terephthalic acid mol ratio of 1.5 and a carboxyl conversion of 95 percent.
The reaction mixture leaving the second reactor-separator is transferred to a third reactor-separator for further esterification and vapor-liquid separation. The third reactor-separator is maintained at a temperature of 275° C. and 350 mm Hg pressure. Residence time in this reactor is 1-2 hours. The product has a reacted glycol to terephthalic acid mol ratio of 1.14 and a carboxyl conversion of 99 percent. The degree of polymerization is about 6. This product is continuously fed into the first of a series of three polycondensation reactors. The first polycondensation reactor is maintained at a temperature of 275° C. and a pressure of 50 mm Hg; the second polycondensation reactor is maintained at a temperature of 285° C. and a pressure of 2 mm Hg; and the third polycondensation reactor is maintained at a temperature of 295° C. and a pressure of 0.5 mm Hg. The final reactor in the series of three polycondensation reactors is an essentially horizontal totally enclosed cylindrical reactor having an essentially horizontal polyester flow, a pool of polyester in its lower portion, and driven wheels to create high surface area in the polyester to facilitate evaporation of volatiles from the polymer. A preferred reactor is described in detail in U.S. Pat. No. 3,976,431. Excellent results are also obtained with use of the reactor described in U.S. Pat. No. 3,728,083.
The polyethylene terephthalate polyester issuing from the last reactor stage has average intrinsic viscosity of 0.96 dl/g. The molecular weight distribution of this polyester is relatively narrow as indicated by the fact that the ratio of the weight average molecular weight (M w ) to the number average molecular weight (M n ) is less than 2.25. The diethylene glycol content is 0.9 percent and the content of chloroform-soluble materials is less than 1.6 percent. The polyester from the last reactor stage is passed at a temperature of 295° C. through a filter distribution plate to a 192-hole spinnerette, and processed into 1300 denier yarn. Quality of the yarn produced is excellent, i.e., tenacity is 9.2 gpd and elongation at break is 14 percent. Moreover, in comparison with the yarn produced in accordance with the process of U.S. Pat. No. 3,689,461, the percentage of yarn defects is decreased by about 7 percent. This improvement is attributed to the improved uniformity of the polyester prepared by the process of the present invention.
EXAMPLE 2
The procedure of Example 1 is followed except that the pressure in the first reactor-separator is varied over the range 100 to 150 psig and the pressure in the second reactor-separator is varied over the range 70 to 120 psig. The process is found operable within these ranges; however, a direct relationship between pressure and reacted glycol to terephthalic acid mol ratio is established. Accordingly, a relatively high pressure in these reactors is preferred because we have found that as reacted glycol to terephthalic acid mol ratio increased, the molecular weight distribution of the final polyester is narrowed and yarn quality improves. We hypothesize that dicarboxylic ended oligomers are less reactive than oligomers containing hydroxyethyl end groups and that they tend to broaden the molecular weight distribution.
EXAMPLE 3
The procedure of Example 1 is followed except that a vapor monitor is installed on the vapor line from the first reactor-separator to monitor carboxyl conversion and reacted glycol to terephthalic acid mol ratio. The carboxyl conversion (C) can be estimated from the equation: ##EQU1## Further, the reacted mol ratio (R) of ethylene glycol (EG) to terephthalic acid (TPA) can be estimated from the equation: ##EQU2## Use of the vapor monitor significantly improved control of the process within the required limits. | In a process for the preparation of high molecular weight linear polyesters of terephthalic acid which comprises partially esterifying terephthalic acid with an alkylene glycol under direct esterification conditions and then further esterifying and polycondensing the partially esterified product, the molecular weight distribution of the polyester is narrowed by correlating the carboxyl conversion with the reacted glycol to terephthalic acid mol ratio in various steps of a multistep process. | 2 |
[0001] This application claims priority on U.S. Application Ser. No. 60/833,492 filed on Jul. 27, 2006, the disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to improvements in the preparation of vaccines for the prevention of viral based diseases and more particularly, vaccines for the treatment of influenza.
BACKGROUND OF THE INVENTION
[0003] The rapid development and deployment of prophylactic and therapeutic vaccines remains a serious problem that is worsening with increased ease of global travel and emerging infectious diseases on the rise. The current technologies for developing and scaling vaccines were most appropriate for an earlier time when infections moved slowly around the globe and surveillance was capable of providing several months to years of warning of an impending outbreak of an existing or emerging pathogen. Several recent infectious diseases outbreaks provide evidence that this extended period of warning to emergence of an epidemic or pandemic is shortening and at an accelerated pace. Recent SARS and avian influenza outbreaks are prime examples of this phenomenon.
[0004] As the world has gotten smaller, diseases that were once relegated to certain parts of the world now can become worldwide because of the availability of air travel and widespread international trade. Because of the vast scope of international trade in the global economy, a number of diseases have spread far beyond their normal boundaries. In addition, many diseases are able to spread more quickly due to, for example, the large volume of air travel. Global warming has also been postulated as having an effect on the spread of disease as well.
[0005] Influenza is one such disease that has benefited from globalization. One strain of Avian flu, A(H5N1) virus has been known in certain areas of Asia for a number of years, but its spread had been fairly limited. More recently, outbreaks of the virus have been seen in widely dispersed areas such as India, Egypt and France that has left international health experts concerned and questioning why the disease is moving so rapidly after being relegated to one area for many years.
[0006] Influenza appears in seasonal epidemics caused primarily by new strains that can result from the spread of an existing flu virus to humans from another animal species. The avian influenza H5N1 that was first discovered in the 1990s was thought to be a prime candidate for causing an influenza pandemic. However, this virus has not so far mutated to spread easily between people.
[0007] Although there are vaccines available for influenza, these are often of limited value. Most influenza vaccines are trivalent in that they include purified and inactivated viruses of three discrete strains. These strains can vary each year as the trivalent influenza vaccine is formulated annually based on influenza strains projected to be prevalent.
[0008] Because it can take a significant period of time to develop the vaccine and test it, there is a high risk that the selected influenza strains are not particularly useful against a given years actual influenza strain. The influenza virus, like all RNA viruses, has a high mutation rate and therefore, over time, these mutations accumulate and eventually the virus evolves into a new strain.
[0009] Current methods for the development of vaccines against these emerging infections are too slow to provide in time protection when faced with a virus that mutates rapidly. There is a high risk that the virus can spread quickly before a vaccine can be developed. As a result, there is a need for a just in time manufacturing system to address this problem.
[0010] Current influenza vaccine production using the well established chicken egg technology, has great difficulty producing enough vaccine on time for the flu season even with a one year notice. In addition, the vaccines made in this manner are contraindicated for people with egg allergies. In the case of pandemic flu, there will not be a one year advance notice and obtaining purified starting material for vaccine deployment will take more time than is available to prevent broad dissemination of the disease.
[0011] It has been proposed that mammalian cell manufacture will have significant advantages over manufacturing in eggs. Although it is more easily scaled, mammalian manufacture does not attenuate the virus and can produce actual pathogenic virus rather than desired strain. More importantly, while larger batches of vaccine may be available earlier with mammalian cell manufacture, the overall gain in production volume (i.e doses) is not significant. The epidemiology of a pandemic is such that mammalian cell produced vaccine would not be available for the first wave of infection where millions may die; vaccine produced in either egg or mammalian cell culture would be available for a second wave of infection.
[0012] The only vaccine manufacturing technology that has the possibility of producing vaccine rapidly enough to protect against the first wave of a pandemic is to use a bacterial host such as E. Coli for expression of protective protein antigens. However the manufacture of such a vaccine in E. Coli is not straightforward. In the case of influenza, where glycosylation of the influenza proteins is critical to providing a protective immune response, E.Coli or other bacterially based manufacture would not be feasible since those systems do not glycosylate protein products. In addition, E. Coli and other bacteria do not serve as hosts for the influenza virus thus making whole, attenuated, or killed virus production impossible in that background. E. Coli and other bacteria can replicate DNA plasmids that contain viral sequences but recent research has shown that direct DNA administration does not produce a protective antibody response. E. Coli and other bacteria can serve as hosts for the production of bacterial viruses, bacteriophage (phage). Recent work has shown that phage can be engineered to express foreign protein sequences on their surface that can act as vaccines. However, as with other proteins expressed in bacteria, these proteins are not glycosylated and thus the constructs are ineffective against pathogens where glycosylation is important in immunity.
[0013] Recently, March and his collaborators have demonstrated that by placing the DNA sequence coding for a known protective antigen of hepatitis B into phage and injecting this recombinant phage into a laboratory animal, a protective response is obtained against hepatitis infection. (Vaccine (2004) April 16;22(13-14):1666-71 Genetic immunization against hepatitis B using whole bacteriophage lambda particles. March J B, Clark J R, Jepson C D. Vaccine (2004) June 23;22(19):2413-9 Bacteriophage lambda is a highly stable DNA vaccine delivery vehicle. Jepson C D, March J B.)
[0014] The target antigen is not expressed on the surface of the phage but rather the phage apparently serves as an effective transfection agent for the animal host cells thereby allowing them to produce the foreign protein. It is important to note that the Hep B vaccine is already produced in E. Coli as a protein subunit vaccine (no glycosylation required) and there is no time urgency in the manufacture of hep B vaccine which is already widely available while less susceptible to seasonal variation. Accordingly, March's use of phage to produce a vaccine where glycosylation and urgency of scalability is irrelevant is very different from the use described herein.
OBJECTS OF THE INVENTION
[0015] It is an object of the invention to provide a vaccine for preventing viral infections.
[0016] It is also an object of the invention to provide a vaccine for RNA viral infections.
[0017] It is another object of the invention to provide a vaccine for influenza infections.
[0018] It is a further object of the invention to provide an improved method of manufacturing vaccines.
[0019] It is still a further object of the invention to provide a just in time method of manufacturing vaccines.
[0020] It is still another object of the invention to provide a method of manufacturing vaccines using a bacteriophage vector.
[0021] It is a further object of the invention to provide a method of manufacturing a vaccine using a bacteriophage vector produced in E. Coli.
SUMMARY OF THE INVENTION
[0022] The present invention provides a new method of vaccine production based on early identification and genetic characterization allowing for generation of scalable vaccine production that is effective and rapid. The present invention is superior to existing and proposed technologies in that: 1) it only requires gene sequence information from the pathogen, 2) the vaccine is rapidly generated without purification and culture of the pathogen, 3) the vaccine is non-pathogenic so it is safe and requires no inactivation, attenuation, or subunit purification, 4) the vaccine is more rapidly scalable than competing technologies, especially where proper glycosylation is important in providing immunity. Using phage as a DNA delivery mechanism for a vaccine against pathogens where glycosylation is critical to immunity is novel and would be unexpected. Phage does not replicate in mammalian cells but the described system allows for host cell production and preserves critical post-translational modifications such as glycosylation that may be critical for development of a protective response.
[0023] This system is a plug and play component system where once a sequence is identified, the time to a clinical production lot is reduced from months or years to weeks. Direct experimentation has shown that H5 immunity in mice can be generated starting from the readily available gene sequence using a bacteriophage vector produced in E. Coli.
[0024] It has been found that pathogens such as emerging infections, bio-warfare agents, or pathogens evolving resistance to treatment where urgency is important and the role of glycosylation is known to be important or is unknown, can be treated with vaccines made by our integrated method of 1) identifying a likely or known protective gene 2) synthesis of the candidate gene 3) insertion of the gene into phage 4) production in bacteria of lots of the phage containing the candidate gene. We have demonstrated this principle using H5N1 influenza. In addition to incorporating the desired gene sequence of the target antigen into the phage DNA, additional modifications can be made to further improve the host immune response. Two such involve the addition of a mammalian signal sequence at the 5′-end of the DNA, and a second is the introduction of the DNA sequence that codes for the addition of a 3′-glycosylphosphatidylinositol anchor structure. The former assists in directing newly synthesized protein into a trafficking pathway within the cell that ensures exposure to the glycosylation machinery while the latter serves to immobilize the protein product on the surface of the cell, increasing local concentration and improving potential interaction with cells of the host immune system.
[0025] Essentially, using optimized production techniques (in terms of growth media, growth conditions, host E. coli strains and a wild type phage, the yield can be as high as 10*15 phage per liter of culture. A 100 Liter Bioreactor can produce 10*17 phage. At a dose of 10*10 phage, this would equate to 10 million doses; (based on animal weight factors as discussed below). The mechanism is believed to be resulting in the translation in these cells of the vector DNA sequence, followed by appropriate glycosylation of the resulting protein product, resulting in an immune response by the host. The mechanism meets the criterion of very rapidly creating a vaccine with only DNA sequence information. It is scalable in E. Coli, and the appropriate antigen/s will be appropriately glycosylated.
[0026] The inclusion of an IRET (Immune Response Enhancement Technology) approach is broadly applicable to the bacteriophage-DNA platform. In essence this involves addition of a DNA sequence to the 5′-end of the protective antigen. This sequence codes for a mammalian signal sequence and ensures direction of the synthesized protein into the secretory pathway and thence to the cell surface. In addition, a second sequence can be added at the 3′ end that codes for addition of a GPI anchor. The latter is a capability of all cells and serves to immobilize the target protein at the cell surface so that the entire amino acid sequence is exo-directed.
[0027] Using phage as a DNA delivery for a vaccine against pathogens where glycosylation is critical to immunity is unique and unexpected. The DNA sequence of a key antigen from the H5 strain of Avian influenza virus was synthesized and cloned into a plasmid for expansion. Excision with restriction endonuclease allowed insertion of the gene sequence into phage lambda using standard methods. The sequence of the inserted fragment was confirmed and recombinant phage prepared in an E. coli host. Phage were purified after lysis by centrifugation and used to immunize mice.
BRIEF DESCRIPTION OF THE FIGURES
[0028] FIG. 1 is a representation showing anti-H5 reactivity over a period of 56 days.
[0029] FIG. 2 is graph showing the effect of dilution of the serum anti-H5 reactivity.
[0030] FIG. 3 shows the amounts of vaccine in normal saline without adjuvant injected on days 0, 15, and 45
DETAILED DESCRIPTION OF THE INVENTION
[0031] In the present invention, a virus vaccine is prepared. The DNA sequence of a virus for which a vaccine is desired is obtained. The complete gene for the virus is synthesized by standard methods and cloned into a plasmid. The gene fragment so produced is sequenced in both directions by established methods to confirm its identity.
[0032] The DNA sequence of interest is inserted into a bacteriophage by excision of the fragment and ligation into the phage using methods well known to those versed in the art. The DNA is packaged into phage heads and the resultant phage grown in E. Coli. Plaques (representing phage-infected bacterial cells) are picked and the isolated phage expanded in standard culture medium. After expansion, the plaques are extracted by lysis and the phage purified by centrifugation, then titered. The resultant phage can be administered to the patient.
[0033] The viruses that the present invention is particularly useful with are RNA viruses. These viruses typically belong to either Group III, Group IV or Group V of the Baltimore classification system. As such they possess ribonucleic acid (RNA) as their genetic material. The nucleic acid is typically a single stranded RNA (ssRNA), but can in some instances double stranded RNA (dsRNA).
[0034] Typical human pathogenic RNA viruses include SARS, influenza and hepatitis C. The present invention has particular applicability to viruses that rely on the expression of specific oligosaccharides for functions such as entry into host cells, correct proteolytic processing and protein trafficking. Examples of such viruses include but are not limited to Hendra, SARS, CoV Influenza and hepatitis C.
EXAMPLE
[0035] Avian Influenza H5 sequence was obtained from Genbank (AY651330 A/bird/Thialand/3.1/2004 (H5N1) HA). (Li, K. S. et al., Genesis of a highly pathogenic and potentially pandemic H5N1 influenza virus in eastern Asia. Nature 430 (6996), 209-213 (2004)) The virus was characterized at Queen Mary Hospital in Hong Kong and reported in a manner typical of emerging pathogens.
[0036] The complete H5 gene was synthesized and the gene product cloned into a pJ4:G03267 plasmid. The fragment had the expected size by agarose gel electrophoresis, and was sequenced in both directions to confirm identity.
[0037] The H5 DNA was inserted into lambda bacteriophage (Uni-ZAP XR Vector Kit and Gigapack cloning kit from Stratagene) by EcoR I excision of the fragment and ligation into the phage.
[0038] The sequence of the inserted sequence was confirmed by PCR and DNA sequencing. The DNA was packaged into phage heads and grown in E.Coli on LB plates. Plaques were picked and expanded in LB broth, extracted by lysis, purified by centrifugation then titered.
[0039] Mice were immunized intramuscularly with 10 8 pfu of vaccine in normal saline without adjuvant on days 0, 15, and 45 and tested for antibody production on days 0, 15, 30, 45 and 56. See FIG. 1 .
[0040] The antibody response in the mice was determined by the use of an IDEXX FlockChek avian influenza virus antibody ELISA kit that is licensed by the USDA for detecting avian influenza serum antibodies in chickens. The test was modified using KPL HRP conjugated goat anti-murine IgG+IgM(H+L) secondary antibody and the KBL SUREBLUE TMB kit for detection. | Bacteriophages are used as a DNA delivery system for a vaccine against pathogens where glycosylation is critical to immunity. | 0 |
[0001] CROSS-REFERENCE TO RELATED PATENT APPLICATION
[0002] This application is a continuation of International Application No. PCT/US14/68388, filed Dec. 3, 2014, which claims the benefit of U.S. Provisional Application No. 61/912,006 filed Dec. 4, 2013, the disclosure of which is incorporated herein by reference.
BACKGROUND
[0003] 1. Technical Field
[0004] Color image processing and display, and in particular, rendering of color images that are perceived to be of high aesthetic quality.
[0005] 2. Description of Related Art
[0006] Current techniques for the rendering of high quality color images include techniques for the sharpening of images. Sharpening of an image is needed when the image has some level of blur. The blur may be caused by camera optics, and/or the image receptor in a digital camera, and/or the lack of steadiness of the camera when the image was acquired. At some level, image blur will be sufficiently high so as to cause a human observer of the image to perceive the image to be of low quality. Additionally, sharpening may be needed because blur in an image prevents a human observer or a computer algorithm from obtaining information from the image that would otherwise be perceivable or available if the image were sufficiently sharp.
[0007] Image and video processing to increase edge sharpness and reduce noise has been used to improve perceived quality since the inception of digital imaging due to the general implementation advantages of processing digital pixels in software or digital hardware over processing analog image and video data with complex analog electronics. Current image processing methods are directed to separate sharpening and noise reduction, with noise reduction most typically occurring before sharpening in order to reduce the visibility of sharpened image and video noise.
[0008] Current algorithms for image sharpening include the “unsharp mask” (UM), digital enhancement filters, and edge based sharpening. Although these algorithms function to sharpen an image, because they preserve local mean values of input still images or video image sequences, they produce unnatural edge transitions. By way of illustration, FIGS. 5A-5C depict a blurred edge in an unprocessed image, the blurred edge sharpened according to a prior art sharpening algorithm, and the blurred edge sharpened according to a method and algorithm of the present invention respectively. It can be seen that the edge of FIG. 5B processed with the prior art algorithm has a “dip” on the low value side of and edge and a “peak” on the high value side of the edge, also called undershoot and overshoot. These are seen as unnatural to viewers and often referred to as glows around edges because they do not represent the type of edge transition from better optics that viewers are familiar with visually. Such glows are perceived negatively by viewers as artifacts in the output images. In contrast, the edge of FIG. 5C has been processed with an algorithm and method of the present invention, as will be described subsequently herein. It can be seen that the edge is narrower, i.e., it has been sharpened, while also not having any overshoot or undershoot.
[0009] Current algorithms such as the unsharp mask also have the undesirable effect of enhancing image noise. Images having enhanced noise have poor aesthetics, i.e., they are perceived by observers to be “unpleasant to look at.” There are variations of the unsharp mask algorithm, such as weighted UM, but these operate such that the weights are dependent upon local pixel mean or edge intensity. Each of these variations of the UM algorithm has its own disadvantages and results in overshoot of edges or other artifacts.
[0010] Additionally, certain currently practiced algorithms and methods have been complex to implement. They may include spatial frequency decomposition of image or video data, with high frequency data treated as noise, and reduced and low frequency data treated as edges, Hence, these methods are not suitable for real time high resolution video image processing. Instead, their use is limited to still image processing.
[0011] Examples of noise reduction in currently practiced and algorithms include, but are not limited to, median filtering, statistical estimation, epilson non-linear gradient filters, and digital smoothing filers. These methods have been shown to be effective for reducing image and video noise but they also reduce edge sharpness, resulting in a need to have a combined method that sharpens edges and reduces noise that can be implemented in real time for high resolution video data.
[0012] In an attempt to address this need, color transformations have been used to calculate the image or video pixel intensity for the sharpening and noise reduction processing to avoid changing color pixel data. These methods used well known color transformations to convert input RGB image or video data to Cie L*a*b* and Cie Luv with L being intensity, or HSV with H being intensity, or processed input RGB data directly with transformation that isolated the G luminance data. Since changing L*, L, H or G also changes color hue and saturation, however, these methods cause color shifts along edges and in noise areas, both of which are perceived negatively by viewers as unnatural artifacts.
[0013] Furthermore, it is noted that most of the currently practiced algorithms are not suitable for software implementation as they require computation of mean or standard deviation around the “pixel of interest.” Current digital cameras have high resolution CCD sensors that have a very large number of pixels; even in cell phones, cameras having 8 megapixel CCDs are now common. With the pixel count of common digital images now being so high, a software implementation of current image sharpening algorithms is computationally prohibitive, especially using the processor in a cell phone, and with the desire by a user to perform image sharpening in a matter of seconds.
[0014] Thus there remains a need for an image sharpening method that can sharpen a color image without enhancing noise in the image, and that is not computationally intensive such that it can be executed on a processor of modest capability and achieve the sharpening in an acceptably short time, and in particular, at a short enough time to enable real time sharpening of images at video of movie sequence rates. Additionally, there is a need for an image sharpening algorithm and method that is able to suppress noise in an image. Additionally, there is a need for an image sharpening algorithm and method that does not cause color shifts along edges and in noise areas.
SUMMARY
[0015] The present invention meets at least one of these needs by providing a method for sharpening of an image. The image may be a grey scale image or a color image. In one aspect of the invention, an algorithm for performing image sharpening combines edge sharpening and noise reduction on image and video data to eliminated artifacts, thereby creating natural looking output images and video without increased noise. The algorithm is simple to implement, using one dimensional look-up tables (1D LUTs) that do not require complex spatial frequency processing of input image and video data. The 1D LUTs reduce differences for small input differences which are likely noise, increase differences for mid-level input differences to increase edge slope and sharpness, and maintain high-level input differences to maintain sharp edges without noise increase on those edges that are already sharp.
[0016] In another aspect of the invention, an algorithm for performing image sharpening uses a two dimensional mask that differentiates between “noise pixels,” which are intended to not be sharpened, and “edge pixels,” i.e. pixels located along the edge of an object in the image, which are intended to be sharpened. In one embodiment, the two dimensional mask may be a 3×3 mask. Other sizes of two dimensional masks are contemplated. In another aspect of the invention, the algorithm is a generalization of an unsharp mask and an c-filter. The strength of the c-filter may be determined by look-up tables (LUT).
[0017] In another aspect of the invention, an algorithm for performing image sharpening implements the sharpness and noise reduction processing on image and video brightness data, using the I data from a Cie IPT transformation of input RGB image or video data to produce output image or video data that does not include color changes that are produced when processing Cie L*a*b*, Cie LUV or RGB image or video data. Processing the I values preserves the color values on edges and therefore does not produce unnatural color artifacts.
[0018] In summary, when sharpening an image according to the algorithms and methods of the present invention, image noise is suppressed, low intensity edges of objects in the image are enhanced, and objects in the image that are already sharp are left unchanged.
[0019] More specifically, in accordance with the present invention, a method of sharpening an input image to produce an output image is provided. The method comprises providing the input image as a digital input image comprised of input image pixels, each input image pixel defined by input image pixel data; identifying center pixels of the digital input image, the center pixels defined as those image pixels that are surrounded by upper and lower vertical pixels, left and right horizontal pixels, and upper left, upper right, lower left, and lower right diagonal pixels; for each of the center pixels, calculating at least four input gradients of intensity relative to the center pixel; defining a gradient minimum value, and a gradient maximum value; applying a gradient gain function to each of the input gradients of intensity for each of the center pixels to produce respective output gradients of intensity for each of the center pixels, wherein the gradient gain function is defined to adaptively vary the amount of gain such that object edges in the input image that are perceived by a human observer to be of low intensity are enhanced, and object edges in the input image that are perceived by a human observer to be sharp are left substantially unchanged; for each of the center pixels, calculating output image pixel data based upon their output gradients of intensity, the output image pixel data defining output image pixels of the output image; and communicating the output image pixel data to an image data receiver.
[0020] In certain embodiments, calculating the at least four input gradients of intensity relative to the center pixel may be comprised of calculating respective input gradients of intensity from the center pixel to the left horizontal pixel, from the center pixel to the right horizontal pixel, from the center pixel to the upper vertical pixel, and from the center pixel to the lower vertical pixel. In other embodiments, calculating the at least four input gradients of intensity relative to the center pixel may be comprised of calculating respective input gradients of intensity from the upper vertical pixel to the lower vertical pixel, from the left horizontal pixel to the right horizontal pixel, from the upper left diagonal pixel to the lower right diagonal pixel, and from the lower left diagonal pixel to the upper right diagonal pixel. In other embodiments, calculating the at least four input gradients of intensity relative to the center pixel may be comprised of calculating respective input gradients of intensity from the center pixel to the left horizontal pixel, from the center pixel to the right horizontal pixel, from the center pixel to the upper vertical pixel, from the center pixel to the lower vertical pixel, from the center pixel to the upper left diagonal pixel, from the center pixel to the lower left diagonal pixel, from the center pixel to the upper right diagonal pixel, from the center pixel to the lower right diagonal pixel.
[0021] The gradient gain function may be a linearly increasing function over a low range of gradients, a constant over an intermediate range of gradients, and a linearly decreasing function over a high range of gradients. Such a the gradient gain function may include a region of negative gain over a second low range of gradients that is less than the first low range of gradients. In one embodiment, the gradient gain function may be a quantized Rayleigh distribution.
[0022] The gradient gain function may be defined using a one-dimensional look-up table containing a gain value corresponding to each gradient value. Alternatively or additionally, the gradient gain function may be defined by the combination of an unsharp mask and a noise suppression filter. The gradient gain function may be further defined to adaptively suppress noise in regions of the input image that are perceived by a human observer to be smooth regions. In certain embodiments, the unsharp mask operates to increase the intensity of edges of objects in the input image that are of low intensity, and the noise suppression filter operates to decrease the intensity of pixel values around the center pixel that are greater than a predetermined threshold amplitude value.
[0023] The input image to be sharpened may be a greyscale or other monotone image, or a color image comprised of input image pixels defined by color tristimulus values. Such color tristimulus values may be RGB tristimulus values, in which case the method may further comprise performing a color transformation to a color space having an image intensity component. The color transformation may be to a color space selected from CieL*a*b*, CieLuv, CieIPT, and HSV.
[0024] The method of sharpening an image may be applied to a plurality of input images defining a video, to produce a plurality of output images defining a sharpened video. In certain embodiments, the image data receiver may be a display device, in which case the method further comprises displaying the image on the display device.
[0025] In accordance with the present invention, a device for sharpening an image is also provided. The device is comprised of a processor in communication with a non-transitory computer readable medium storing an algorithm communicable to and executable by the processor. The algorithm includes the steps of sharpening an input image as described above and subsequently herein. The device may include an image data receiver, which, in certain embodiments, may be an image display. Alternatively, the image data receiver may be a non-transitory computer readable medium, such as a memory, or a data storage disc, either of which may be portable. The device may further include a data input port in communication with a source of the digital input image and in communication with the processor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The present disclosure will be provided with reference to the following drawings, in which like numerals refer to like elements, and in which:
[0027] FIG. 1 is a 3×3 matrix that may be used in an unsharp mask algorithm for sharpening images;
[0028] FIG. 2 is an exemplary Laplacian matrix that may be used as a high pass filter in executing an unsharp mask algorithm for sharpening images; and
[0029] FIG. 3 depicts an first exemplary gradient versus gain function that may be used in a combined noise suppression and sharpening filter of the present disclosure;
[0030] FIG. 4 depicts a second exemplary gradient versus gain function, which is a Rayleigh based distribution that may be used in the combined noise suppression and sharpening filter; and
[0031] FIGS. 5A-5C depict a blurred edge in an unprocessed image, the blurred edge of the unprocessed image sharpened according to a prior art method and algorithm, and the blurred edge of the unprocessed image sharpened according to a method and algorithm of the present invention, respectively.
[0032] The present invention will be described in connection with certain preferred embodiments. However, it is to be understood that there is no intent to limit the invention to the embodiments described. On the contrary, the intent is 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
[0033] For a general understanding of the present invention, reference is made to the drawings. In the drawings, like reference numerals have been used throughout to designate identical elements. Additionally, as used herein, a “non-transitory computer readable medium” is meant to include all computer readable media, including but not limited to hard disks, compact disks, digital video disks, flash memory, random access memory, read-only memory, cache memory, and register memory; and to not include a transitory propagating signal
[0034] As noted above in the SUMMARY, an algorithm in accordance with the present disclosure is a generalization of an unsharp mask and an c-filter. Further details on the unsharp mask, and on the c-filter will now be presented.
[0035] Unsharp Mask
[0036] The unsharp mask (UM) is a known method for image sharpening. It may be practiced according to the following equation:
[0000] p out =p 0 +λ.h ( P ), (1)
[0037] where p out is the output pixel intensity or the resultant intensity, p 0 is the “pixel of interest” (also referred to herein as the input pixel or the “center pixel”), P−{p 0 , p 1 , . . . p 8 } is the 3×3 input pixel window vector, h(P) is a high pass version of an input image to be sharpened, and λ is a sharpening strength parameter. It is noted that λ is a constant, and therefore does not vary with the strength of an edge.
[0038] In applying the unsharp mask algorithm, one may use a 3×3 mask, also referred to herein as a window 100 , as shown in FIG. 1 . Additionally, one common high pass filter that may be used is a 4 or 8 neighbor Laplacian matrix. An exemplary filter or mask 200 is shown in FIG. 2 .
[0039] Thus Equation (1) can be rewritten as follows:
[0000]
p
out
=
p
0
-
λ
·
∇
2
(
P
)
,
=
p
0
+
λ
·
[
∑
i
=
1
8
(
p
0
-
p
1
)
]
,
=
p
0
+
λ
·
[
∑
i
=
1
8
Δ
p
i
]
.
(
2
)
[0040] Two observations are noteworthy with regard to performing image sharpening via this unsharp mask algorithm:
[0041] (1) There are artifacts in an image that is sharpened using this unsharp mask. The algorithm is susceptible to noise, i.e., noise in an image will be increased. This deficiency may result in distortion and halos around sharp edges of objects in the image if the sharpening strength is high.
[0042] (2) The algorithm will enhance sharp edges, as well as noise, which are desired to be left as is and not be further sharpened.
[0043] In view of the above observations, the Applicants have realized that a different approach towards image sharpening is needed, which depends upon the strength of object edges, and which provides reduction of noise in an image. Also, it is desirable that an image sharpening function applies equal gain to all gradients, i.e., differences between pixels, in the image, thereby leading to intensity saturation of pixels to minimum and maximum values (e.g. 0 and 255 for 1 byte per channel).
[0044] The Applicants have further realized that there is a need for sharpening to operate as a gain function that increases with the increase in gradient and then ramps-down after a certain cut-off to avoid intensity saturation to minimum and maximum.
[0045] ε-Filter
[0046] The ε-filter is a known method to reduce image noise. It may be practiced according to the following equation:
[0000]
p
out
=
p
0
+
∑
i
=
1
8
w
i
f
(
p
o
-
p
i
)
,
=
p
0
+
∑
i
=
1
8
w
i
f
(
Δ
p
i
)
,
=
p
0
+
∑
i
=
1
8
w
i
f
i
Δ
p
i
.
(
3
)
[0047] where p out and p 0 are as defined above, w i are the weights in the range [0,1],
[0000]
f
(
x
)
=
{
ɛ
,
x
>
ɛ
x
,
x
<
ɛ
-
ɛ
,
x
<
-
ɛ
,
and
∑
w
i
=
1.
[0048] This final condition on the weights, Σw i =1, ensures that the image intensity stays constant. If that is not a requirement for the particular image sharpening application, then that condition can be removed. It is also noted that the last step in equation set (3) is possible, because it is a discrete curve and ƒ i can be adapted from ƒ such that the last step holds, i.e., is true. Because the pixel values are discrete, the function ƒ can be defined at each of the values as given in the equation above such that the two equations are mathematically equivalent. This is a key aspect of the invention.
[0049] In summary, the operation of this ε-filter is clear: it suppresses any noise that is greater in amplitude than the threshold amplitude ε around the center pixel.
[0050] Combined Noise Suppression and Sharpening Filter
[0051] In accordance with the present disclosure, the Applicants' method of adaptive sharpening in image processing and display includes a combined noise suppression and sharpening filter. Attributes of this filter include, but are not limited to the following:
[0052] Suppression of noise present in the image, especially in the smooth regions (i.e., regions that do not include edges of objects) where artifacts are more perceptible (in a negative manner) to a human observer.
[0053] Prevention of intensity saturation to minimum and maximum. Typically, the minimum to maximum are 0 and 255 but could be any pre-defined range based on a given application.
[0054] Enhancement of object edges of that are low intensity, i.e., not clearly visible, thereby result in the best gain in image quality as perceived by a human observer.
[0055] No action (i.e., no enhancement of) very sharp edges, because processing such edges will only result in artifacts, and not an improvement of image quality.
[0056] In order to provide these attributes, it has been determined that the sharpening strength function must be dependent on the gradient calculated in the 3×3 (or larger) window (such as window 100 of FIG. 1 ) with respect to the center pixel. This may be accomplished by rewriting equation (2) to have the following form:
[0000] p out =p 0 +Σ i=1 8 λ i Δp i . (4)
[0057] A significant change to equation (2) is to move the sharpening strength parameter λ to within the summation sign; in other words, λ becomes λ l and is thus a variable dependent upon i instead of being a constant. Accordingly, λ can be adapted to the strength of a gradient Δp i .
[0058] Comparing equation (3) with equation (4), the Applicants have realized that for sharpening, it is not required to maintain the average intensity of an image since edges are enhanced, and furthermore, that functions f i , and λ i can be combined into one function. For values under ε, the combined function will be a noise reduction filter. For larger values it will act as a sharpening filter. Since the sharpening strength λ has been made a variable λ i that is dependent upon the gradient strength, the behavior of the sharpening function is modified, so as to perform sharpening in an adaptive manner.
[0059] The combined filter is a rewriting of equation (4), with introduction of a new combined function, c i .
[0000] p out =p 0 +Σ i=1 8 c i Δp i . (5)
[0060] It is noted that for an 8-bit input image, c i is a 511 point function.
[0061] An adaptive sharpening algorithm that includes equation (5) has the flexibility to operate under the assumption that smaller gradients in the filter window are due to the noise present in the image.
[0062] The modifications in the gradient gain function, or the gradient weight, i.e. the gain applied to the gradient are as follows:
[0063] As the details increase the gain is increased. However, increasing the gain function continuously may lead to saturation to the maximum value. This can be avoided by reducing the enhancement gain after some point. This region represents edges with low intensity. If the gain is, for example, 2.0 for input intensity 128 and gradient 64, then the gradient of output will saturate (128+2×64=256) and any higher value will saturate to 256. Therefore, the weights for any higher values can be reduced, all the way down to 0.
[0064] As the gradient or the edge intensity increases, the gain is reduced until finally it is reduced to zero for high intensity edges.
[0065] For the purpose of illustration, FIG. 3 depicts a first exemplary gradient versus gain function 300 . In this example, epsilon (c) has a chosen value of 8 and the maximum sharpness gain is chosen to be 2. It can be seen in FIG. 3 that the entire range of gradients from 0-255 (assuming 8 bits per pixel) is subdivided into five bands of gains as follows:
[0066] Region of negative gain 302 : this is the smoothing region. The initial slope of portion 301 is “−x” and then portion 303 having a slope of “x.”
[0067] Region 304 of high gain for gradients.
[0068] Flat gain region 306 .
[0069] Decreasing gain region 308 for very (and increasingly) sharp edges.
[0070] FIG. 4 depicts a second exemplary gain function 400 . In this example, a Rayleigh based distribution, i.e., a continuous probability distribution, is used, and the table is then quantized. (It is noted that the use of Rayleigh distribution as a gain function is only one example or illustration of a gain function. The gain function may be could be any non-linear function that is operable to adaptively sharpen edges in an image that are perceived by a human observer to be of low intensity, while leaving edges in an image that are perceived by a human observer to be of high intensity substantially unchanged. It is further noted that in general, a Rayleigh distribution is a continuous function, so it needs to be discretized/quantized as shown in FIG. 4 , for it to be able to be applicable to image pixel data.) A first region 402 of the function 400 has negative contribution, but the region 402 is very small. This example shows the ability of the Applicants' adaptive sharpening method to effect a tradeoff between smoothing and sharpening.
[0071] Other gain functions are contemplated including, but not limited to, a Weibull distribution function. The gain functions may be based on any other function that fulfills the sharpening gain requirements of the user as described above.
[0072] Computational Aspects
[0073] Certain additional features of the adaptive sharpening algorithm may be provided, which reduce the degree to which the algorithm is “computation intensive,” thereby reducing image processing volume and speed requirements. Advantageously, in circumstances in which the computational power of a processor that executes the algorithm is low, the simplified algorithms described below are still executable by such a processor.
[0074] In executing the adaptive sharpening algorithm, in order to avoid the need for computation of gradients and their subsequent multiplication with the coefficients, a two dimensional look-up table (LUT) may be created in which each index or address of this LUT will store the product of the coefficient and the gradient with respect to the center pixel. Referring to FIG. 1 , the first index/dimension of this LUT will be the center pixel p 0 and the second index/dimension the LUT will be the neighboring pixel p 1 . For accessing the product of c 0 *(p 0 -p 1 ), the LUT will be indexed as LUT[p 0 ][p 1 ].
[0075] Assuming 8 bits per pixel, the total size of the above mentioned LUT will be 256×256=65536=64K.
[0076] If a further reduction in LUT size is desired, then the center pixel p 0 can be quantized to 6 bits. Thus the memory required will be reduced to 64×256=16384=16K. The Applicants have determined through experimentation that quantization of the center pixel does not cause any noticeable degradation in video quality.
[0077] It is further noted that the algorithm can work on only an individual Y, U, or V component of an image defined in the YUV color space, or H, S, of V component of an image in the HSV color space, or all three RGB components simultaneously. (It is further noted that applying sharpening to only the Y, U, or V component reduces the artifacts described previously herein.)
[0078] The pseudo code of the 2D adaptive sharpening algorithm for a single pixel, as described above, is presented as follows:
[0079] 1. Load 9 pixels, the center pixel p 0 and the 3×3 pixel window.
[0080] 2. For each pixel pair, get the product of the gradient and coefficient from the LUT:
[0081] BaseLUT=LOAD(p0)
[0082] Res0=LOAD(BASELUT+p1)
[0083] Res1=LOAD(BASELUT+p2)
[0084] Res2=LOAD(BASELUT+p3)
[0085] Res3=LOAD(BASELUT+p4)
[0086] Res5=LOAD(BASELUT+p5)
[0087] Res6=LOAD(BASELUT+p6)
[0088] Res7=LOAD(BASELUT+p7)
[0089] Res8=LOAD(BASELUT+p8)
[0090] 3. Compute the output as:
[0091] Res9=p0 +Res0
[0092] Res10=Res9+Res1
[0093] Res11=Res10+Res2
[0094] Res12=Res11+Res3
[0095] Res13=Res12+Res5
[0096] Res14=Res13+Res6
[0097] Res15=Res7+Res8
[0098] Res16=Res14 +Res15
[0099] Four-Gradient Approach
[0100] In order to increase image processing speed and/or reduce computational requirements of an image processor, in certain embodiments, the algorithm is further modified such that only four gradients are considered in the adaptive sharpening method instead of all eight gradients. More specifically, in one embodiment, the four corners values in the 3×3 mask are neglected. In this embodiment, equation (5) can be rewritten as follows:
[0000] p out =p 0 +Σ i=2,4,5,7 c i Δp i . (6)
[0101] Accordingly, the above expression requires the computation of only four gradients. The number of additions to compute the output pixel is also halved.
[0102] The pseudo code of the Four-Gradient 2D adaptive sharpening algorithm for a single pixel is presented as follows:.
[0103] 1. Load all five pixels, i.e., the center pixel p 0 , the two horizontal neighbors p 4 and p 5 , and the two vertical neighbors p 2 and p 7 in a 3×3 pixel window. (See FIG. 1 for pixel locations.)
[0104] 2. For each pixel pair get the product of the gradient and coefficient from the LUT:
[0105] BaseLUT=LOAD(p 0 )
[0106] Res0=LOAD(BASELUT+p 2 )
[0107] Res1=LOAD(BASELUT+p 4 )
[0108] Res2=LOAD(BASELUT+p 5 )
[0109] Res3=LOAD(BASELUT+p 7 )
[0110] 3. Compute the output as:
[0111] Res4=P 0 +Res0
[0112] Res5=Res4+Res1
[0113] Res6=Res2+Res3
[0114] Res7=Res5+Res6
[0115] Further Simplifications For Software Porting
[0116] Further simplifications of the algorithm may be performed, and are applicable to a 3×3 window as shown in FIG. 1 . The simplifications pertain to the gradient calculation and the use of a static look-up table as follows:
[0117] Gradient calculation: In the original algorithm, the gradients are computed with respect to the center pixel. To adopt a simpler approach, while performing a lesser number of gradient calculations, the gradients can be computed as (p 2 -p 7 ), (p 4 -p 5 ), (p 1 -p 8 ) and (p 3 -p 6 ), where (p 2 -p 7 ) and (p 4 -p 5 ) represent the vertical and horizontal edge pixels, respectively; and (p 1 -p 8 ) and (p 3 -p 6 ) represent the diagonal edges, all as depicted in FIG. 1 .
[0118] Static LUT: Instead of computing filter coefficients in situ based on the gradients as derived in step 1 above, the static filter coefficient sets may be computed and stored in one or more look-up tables (LUTs). The filter sets are selected based on the combination of the horizontal and vertical gradients. The diagonal edges are always given a constant filter coefficient i.e. irrespective of the gradient; in other words, the ratio of contribution of the diagonal edges to the sharpening is fixed.
[0119] Multiple stored look-up tables may be provided for a variety of different purposes. In certain embodiments, the look-up tables may be defined based on the magnitude of the sum of input pixel differences, with smaller pixel difference increases for larger input pixel difference sums. Alternatively, they may be defined based on average values for the input neighbor pixels, thereby adjusting sharpening and noise reduction differently for dark and bright input image and video blocks. The look-up tables may be defined to process the input pixel differences with user selected levels of sharpness increase and/or user selected levels of noise decrease
[0120] The values in the look-up tables, and the resulting table that is selected for image sharpening may be based upon the imaging application, the objects in the image to be displayed, and/or the type of display that is rendering the image. For example, the different look-up tables may be defined for different image or video data types including but not limited to games, movies, personal photos, military intelligence image or video data, medical modality image or video data, and commercial image or video data for exploration or industrial analysis. Additionally, for a given input image or sequence of images, different look-up tables may be chosen using additional information about the type of data in the image to be sharpened, including but not limited to information about whether the image includes faces or skin, text, graphics, uniform data, or structured/patterned data such as trees or grass. Additionally, the different look-up tables may be defined for different displays that are to render the image(s), including but not limited to televisions, computer monitors or computer screens, smartphones, tablets, and digital signs. Additionally, the different look-up tables may be defined based upon information about the importance of a particular image or image block to the user/viewer of the output image. The values in the look-up tables may be defined based upon a model of the human visual system region adaptation to image brightness.
[0121] It is further noted that one of the disadvantages of sharpening using the 3×3 window is that it can result in jagged edges that are too close to the horizontal or the vertical line or direction, i.e., a line or a column. This is due to the edge detection being limited to the maximum slope that can be detected using a 3×3 window. Also, for very large images and 4K video (i.e. video having a horizontal resolution on the order of 4000 pixels), the range of frequencies that such a window can accommodate may not be sufficient. A larger window may be necessary.
[0122] If an image processor is provided that has sufficient computational capability, then the window size may be increased to 5×5, or 3×5, or any other larger size. A 3×5 window may be more applicable to video images because more edges are along the horizontal direction. Accordingly, the algorithms disclosed herein are applicable to a 3×5 window, as will be apparent to one skilled in the art.
[0123] It is noted that the methods of the present invention may be performed by a device for sharpening an image comprising a processor in communication with a data input port for receiving input data of a digital image, and also in communication with a non-transitory computer readable medium that stores one or more of the adaptive sharpening algorithms described herein. The algorithms are communicable to and executable by the processor. The device may be further comprised of an image data receiver that is in communication with the processor, and that receives the output image pixel data defining output image pixels of the output image. In certain embodiments, the image data receiver may be a non-transitory computer readable medium, such as a memory, or a data storage disc, either of which may be portable, i.e., separable from the processor and transportable to interface with another computer or communications port or network. In other embodiments, the image data receiver may be an image display.
[0124] In certain embodiments, the device for sharpening and (optionally) noise reduction of an image may include a camera that captures still images or a sequence of images as a video or movie. In such embodiments, the sharpening and noise reduction of the images may be performed in real time using the device itself.
[0125] Alternatively, the methods may be performed in real time using a device that is separate from the device that is providing the digital input image. Such separate devices include but are not limited to a separate computer, tablet, or smartphone in the hardware and/or software thereof, in an image or video display, in an attached processor of images received via cable or wireless transmission, or in a central processing facility prior to image or video creation or reprocessing for improved libraries or distribution.
[0126] Additionally, it is noted that the resulting images (which have enhanced sharpness) produced by the methods of the present disclosure may be further processed to have enhanced contrast and/or enhanced brightness. Such further image processing may include the image processing using the Contrast methods as disclosed in the Applicant's commonly owned copending international application, Docket No. RPT0001 WO, entitled “ADAPTIVE CONTRAST IN IMAGE PROCESSING AND DISPLAY,” the disclosure of which is incorporated herein by reference.
[0127] It is, therefore, apparent that there has been provided, in accordance with the present invention, a method for sharpening of an image. Having thus described the basic concept of the invention, it will be rather apparent to those skilled in the art that the foregoing detailed disclosure is intended to be presented by way of example only, and is not limiting. Various alterations, improvements, and modifications will occur to those skilled in the art, though not expressly stated herein. These alterations, improvements, and modifications are intended to be suggested hereby, and are within the spirit and scope of the invention. Additionally, the recited order of processing elements or sequences, or the use of numbers, letters, or other designations therefore, is not intended to limit the claimed processes to any order except as may be specified in the claims. | A method for sharpening of an image. The method combines edge sharpening and noise reduction on image and video data to eliminated artifacts, thereby creating natural looking output images and video without increased noise. The algorithm uses one dimensional look-up tables not requiring complex spatial frequency processing of input image and video data. The look-up tables reduce differences for small input differences which are likely noise, increase differences for mid-level input differences to increase edge slope and sharpness, and maintain high-level input differences to maintain sharp edges without noise increase on those edges that are already sharp. A device for sharpening an image is also disclosed, comprising of a processor in communication with a non-transitory computer readable medium storing the sharpening algorithm communicable to and executable by the processor. | 7 |
BACKGROUND OF THE INVENTION
This is a continuation of abandoned U.S. patent application Ser. No. 08/312,177 filed on Sep. 26, 1994, which is a continuation of abandoned U.S. patent application Ser. No. 08/002,008 filed on Jan. 8, 1993. This invention rotates to a mechanical system used to establish a structural connection between a remote tool and remote mechanisms. More specifically, the invention provides means for establishing a connection between a remote tool and a subsea well structure so that mechanisms on the well structure can be maintained or operated.
In the subsea oil industry, oil production operations are often carried out at the surface of the ocean floor at depths or under conditions that are unsuitable for divers. These operations--drilling, completion, installation, production, and service--are carried out from platforms or barges located above the ocean floor using remote systems that do not require divers.
A specific operation involves mechanically releasing hydraulic connectors being used for subsea christmas tree and tree cap connections. The mechanical release of such connectors requires the exertion of large force upon a connector unlocking mechanism. Prior art devices for carrying out such operations from a remote location require posts or similar additional structures to be attached to a release plate in order to enable a remotely operated tool to engage and lift the plate. Other prior art devices include tree connector mechanisms attached to toggle mechanisms that require a remote tool with pistons to push the toggle mechanisms to unlock the connectors.
The above-mentioned prior art devices present problems because they involve complex structures requiring more parts which increases overall costs and potential for failure.
SUMMARY OF THE INVENTION
The present invention provides a reliable subsea remote release device for operating remote mechanisms including, for instance, mechanically releasing subsea hydraulic connectors that overcomes the above-mentioned problems. The release device of the present invention is capable of exerting a large force upon a connector locking mechanism and is constructed from few, easily manufactured parts.
The main components of the release device comprise an actuating piston and a release arm. The actuating piston and release arm form part of an actuating assembly which is brought into position so that the assembly will cause the release arm to operatingly engage a release lift plate for a tree cap on a tree cap assembly.
The release device enables the release arm to properly align with the release lift plate automatically. The release device can selectively lock or unlock from the release lift plate. Furthermore, the release device enables the use of a circular connector release lift plate which eliminates the need for aligning the release device and the lift plate in a particular angular orientation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of the release device mounted to a remote tool assembly which is in engagement with a tree cap assembly.
FIG. 2 is a sectional view of the release device mounted to a remote tool assembly which is in a release position with respect to a tree cap assembly.
FIGS. 3-10 are fragmentary views showing the release arm of the release device in various sequential positions from a retracted position to engagement with a release lift plate.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a release device 10 mounted to a funnel-shaped tool body assembly 11 for engaging and manipulating a remote assembly. The remote tool assembly 11 is engaged with a tree cap assembly 12 so that operations requiring the remote tool assembly 11 can be carried out on the tree cap assembly 12. The release device 10 comprises a double-acting actuator assembly 13. The double-acting actuator assembly 13 comprises an ordinary piston-cylinder assembly generally known to those skilled in the art, which includes a cylinder housing for containing a pressurized medium and a piston therein. The double-acting actuator assembly 13 includes a piston rod 14. Pivotally attached at all times during the operation of the remote tool assembly 11 to the piston rod 14 by a first pin 15 is the release arm 16. The release device 10 further comprises side plates 17 which extend along opposite sides of the release arm 16 and support a second pin 18.
The release arm device 16 comprises a hook end 19, a lifting surface 20, a tip end surface 21, an elongated body section 22, an extending section 23, and a pin contact surface 24. The release arm device 16 is of such size and shape that when the piston rod 14 is in a retracted position the release arm device 16 is retracted such that no portion of the release arm device 16 extends past the inner funnel surface 25 of the funnel-shaped remote tool assembly 11, enabling clearance of the release arm 16 with respect to any part of the tree cap assembly 12 during engagement or disengagement.
When the units tool assembly 11 engages a tree cap or tree upper frame as shown in FIG. 1, the double-acting actuator assembly 13 can be activated to operate the release arm 16 to engage the underside a release lift plate 26 and apply an upward lifting force upon retraction of the piston rod 14. FIGS. 3-10 illustrate the motion of the release arm 16 during this sequence.
Initially, the release arm 16 is positioned as shown in FIG. 3, clear of the inner funnel surface 25 of the remote tool assembly 11. When the double-acting actuator assembly 13 is actuated, piston rod 14 is extended downward, lowering the release arm 16 past the inner funnel surface 25 tool toward release left plate 26 as shown in FIG. 4. As shown in FIG. 5, the piston rod 14 will advance the release arm 16 until the tip end surface 21 of the release arm 16 contacts a top, beveled outside diameter surface 27 of release lift plate 26. The downward motion of the piston rod 14 and release arm 16 continue so that the tip end surface 21 slides along the beveled surface 27 causing the release arm 16 to pivot about first pin 15, as shown in FIGS. 6-7. Once the tip end surface 21 has cleared the beveled surface 27, the release arm swings back, under gravity, to a piston as shown in FIG. 8. Next, the piston rod 14 is retracted so that lifting surface 20 is brought into contact with a lower portion of the release lift plate 26 as shown in FIG. 9. Applying further retraction force through piston rod 14 will lift release plate 26 for releasing the connection.
To disengage the release arm 16 from the release plate 26, the piston rod 14 is extended beyond the position shown in FIG. 8 so that the pin contact surface 24 of the extending portion 23 contacts second pin 18 causing the release arm to pivot about first pin 15 in a direction away from release plate 26.
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. | A release assembly for operating a remote mechanism such as a subsea well connector includes a funnel-shaped body adapted to engage the well connector and a movable arm adapted to engage and disengage a locking cap of the well connector and provide lifting force in order to actuate the locking cap. | 8 |
This application is a Divisional of U.S. patent application Ser. No. 10/175,415, entitled Multiple Degree of Freedom Compliant Mechanism, filed on Jun. 19, 2002, now U.S. Pat. No. 7,093,827 which claims the benefit of U.S. Provisional Application Ser. No. 60/336,995, entitled Six Degree of Freedom Flexure Stage, filed on Nov. 8, 2001.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates generally to precision alignment machines and mechanisms. More particularly, this invention relates to a compliant mechanism enabling relative movement between a stage portion and a support structure to be controlled with a relatively high degree of accuracy and precision with up to six degrees of freedom.
(2) Background Information
There is a growing need for fine motion control and positioning at meso, micro, and nano scales. Examples include active alignment of components in fiber optics packages, x-y stages with nanometer level resolution, and machine elements for meso- and micro-scale machinery.
Culpepper, in U.S. patent application Ser. No. 10/005,562, filed Nov. 8, 2001, entitled “Apparatus and Method for Accurate, Precise, and Adjustable Kinematic Coupling”, (the '‘562 patent’) which is fully incorporated herein by reference, discloses an adjustable kinematic coupling in which one or more of the kinematic elements (e.g., balls and grooves) may be rotated about or translated along an axis thereby effecting a relative movement between two components. The coupling is well suited for applications where alignment with nanometer/microradian accuracy and precision (i.e., repeatability) and/or where controlled adjustment of the relative position of the coupled components is required.
An alternate approach to fabricating machines requiring fine motion control and positioning has employed the use of compliant mechanisms, and in particular monolithic compliant mechanisms. These compliant mechanisms, however, have typically been planar in nature, having the ability to control at most two translational degrees of freedom and one rotational degree of freedom (i.e., x, y, and θ z ). Examples include a rotational flexure stage for positioning a wafer relative to a microlithography projector disclosed by Barsky in U.S. Pat. No. 5,083,757, entitled “Rotational Flexure Stage”; a precision in plane (i.e., x, y, and θ z ) stage for optical components disclosed by Hale in “Principles and Techniques for Designing Precision Machines”, Ph.D. Thesis, M.I.T., Cambridge, Mass., 1999, p. 184; and a flexure-hinge guided motion nano-positioner disclosed by Elmustafa, et al. in “Flexural-hinge Guided Motion Nano-positioner Stage for Precision Machining: Finite Element Simulations,” Precision Engineering, 2001, vol. 25, pp. 77-81.
Next generation applications (e.g., fiber optic alignment) will likely require compliant mechanisms capable of providing high resolution (i.e., nanometer/microradian) position control with six degrees of freedom (i.e., x, y, z, θ x , θ 74 , and θ z ). Therefore there exists a need for new and improved flexures and/or compliant mechanisms that may be suitable for next generation applications.
SUMMARY OF THE INVENTION
One aspect of the present invention includes a compliant mechanism. The compliant mechanism includes a stage and a support both coupled to a plurality of flexure hinges, and at least one tab coupled to at least one of the flexure hinges. The tab is sized and shaped so that displacement of the tab results in a displacement of the stage relative to the support in any one or more of six degrees of freedom.
In one variation of this aspect, the compliant mechanism is of monolithic construction and includes a stage coupled to three flexure hinges. Three tabs are each coupled to a mutually distinct one of the three flexure hinges. A plurality of support beams are coupled to the three tabs, and at least one support member is coupled to the support beams. The support member includes at least one mount for fastening the compliant mechanism to another structure. The three tabs form lever arms and are coupled to the support beams at three fulcrum points. Displacement of any one of the three tabs generates a displacement of the stage relative to the support member(s) and enables the relative position between the stage and the support member(s) to be adjusted in any one or more of six degrees of freedom.
In another aspect, this invention includes an apparatus of a substantially monolithic construction including first and second reference frames, and at least one flexure hinge coupled therebetween. An actuator is coupled to the flexure hinge(s). Movement of the actuator generates displacement of the first reference frame relative to the second reference frame in any one or more of six degrees of freedom.
In still another aspect, this invention includes a method of aligning a first component and a second component to one another. The method includes using a compliant mechanism including a stage coupled to a plurality of flexure hinges, at least one tab coupled to one of the flexure hinges, and at least one support coupled to the tab(s). The method further includes fastening the first component to the stage, fastening the second component to the support, and displacing the tab(s) to effect a change in position of the first component relative to the second component in any one or more of six degrees of freedom.
In a further aspect, this invention includes a method of fabricating a compliant mechanism. The method includes providing a substantially planar work piece, forming a stage in the work piece, the stage being coupled to a plurality of flexure hinges, and forming at least one tab in the work piece, the tab(s) being coupled to one of the flexure hinges. The method further includes forming at least one support in the work piece, the support being coupled to the tab(s). The tab is sized and shaped so that displacement of the tab(s) results in a displacement of the stage relative to the support member(s)in any one or more of six degrees of freedom.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of one embodiment of a compliant mechanism fabricated in accordance with the present invention;
FIG. 2 is a plan view of another embodiment of a compliant mechanism fabricated in accordance with the present invention; and
FIG. 3 is a plan view of still another embodiment of a compliant mechanism fabricated in accordance with the present invention.
FIG. 4 a is a plan view of the compliant mechanism of FIG. 1 ;
FIG. 4 b is a plan view of the compliant mechanism of FIG. 4 a showing the effect of an exemplary actuation of one tab;
FIG. 5 a is a plan view of the compliant mechanism of FIG. 1 showing the effect of an exemplary actuation of two tabs;
FIG. 5 b is a plan view of the compliant mechanism of FIG. 1 showing the effect of an exemplary actuation of three tabs.
DETAILED DESCRIPTION
Referring to the accompanying figures, the present invention is directed to a flexure based mechanism, also referred to as a compliant mechanism or a planar compliant mechanism that may meet the stringent demands of next generation processes. The compliant mechanism is well suited for applications where alignment with nanometer, micron or millimeter scale accuracy and precision (i.e., repeatability) and/or where controlled adjustment of one component (e.g., an optical fiber) relative to another component (e.g., an optical lens) is required. Exemplary applications to which this invention may be well suited include, but are not limited to, precision automation, precision actuated motion stages, optical mounts, and assemblies such as precision fiber optic alignment machines, semiconductor and microelectromechanical mask alignment, structures with integrated precision actuation methods, micro testing and measurement devices, and other precision alignment devices.
In one embodiment, the present invention includes a planar compliant mechanism having an inner stage coupled to one or more relatively simple compliant elements, such as flexure hinges and tabs, that may utilize both elastic and plastic material deformation. Actuation of one or more of the tabs tends to result in relative movement between two reference frames, one fixed to the inner stage, the other fixed to a support member. In general, in plane actuation of the tabs tends to result in in plane motion while out of plane actuation tends to result in out of plane motion of the inner stage relative to the support member (in plane motion typically refers to motion in the x, y, and θ z directions, while out of plane motion typically refers to motion in the θ x , θ y , and z directions). In a generally desirable embodiment, an inner stage is coupled to three flexure hinges, which are further coupled to three tabs. Although each flexure hinge is shown being axially aligned with corresponding tabs, the tabs may be offset or otherwise disposed off-axis relative to their corresponding flexure hinge, without departing from the spirit and scope of the present invention. Actuation of any one or more of the three tabs may provide for precision alignment in up to six degrees of freedom.
The present invention may be advantageous in that it provides for an improved compliant mechanism and method which enables accurate and repeatable location of two or more components, surfaces, assemblies, and the like, which overcomes at least one of the above-described limitations of prior alignment mechanisms. Another potential advantage of this invention is that it enables the relative position of the coupled components to be adjusted in any one or more of the six degrees of freedom by controlled actuation of one or more tabs. Yet another potential advantage of this invention is that the relative positions of the coupled components may be repeatedly adjusted. Still another potential advantage of this invention is that it may utilize both elastic and plastic deformation of the compliant mechanism's structure. A further advantage of this invention is that it may provide for an adjustable compliant mechanism with a sufficiently high displacement ratio (ratio of actuator input motion to output motion) to produce relatively small output movements (potentially sub-nanometer) with inputs that may be at least one order of magnitude larger.
This invention tends to be further advantageous in that it may be adapted for use with micro, meso, and macro scale applications. Furthermore, the tabs may be actuated using substantially any known, or yet to be developed, means. For example, comb drives may be utilized for MEMs applications, piezo electric actuators for meso scale machines, and conventional mechanical actuators for meso-macro scale applications.
Embodiments of this invention may be still further advantageous in that they are of a monolithic construction, which tends to reduce and/or eliminate friction induced hysteresis and wear that results from the repeated rubbing of components against one another, such as in a conventional contact based or segmented mechanism. These and other advantages of this invention will become evident in light of the following discussion of various embodiments thereof.
Referring now to FIG. 1 , one embodiment of a planar compliant mechanism 100 of the present invention is illustrated. The compliant mechanism 100 is typically (although not necessarily) of monolithic construction (i.e., made from a single piece of material). The compliant mechanism 100 includes a stage 110 , coupled to a plurality (e.g., three) of flexure hinges 120 a, 120 b, and 120 c, which may be uniformly spaced thereabout (i.e., in the form of a substantially equilateral triangle). Inner stage 110 may optionally include a center aperture 112 through which a chuck or some other component may extend. Stage 110 may further optionally include other features, such as but not limited to, holes, slots, grooves, and the like for mounting one or more components thereto.
Flexure hinges 120 a , 120 b , and 120 c are-coupled to inner stage 110 at hinge points 122 a , 122 b , and 122 c , respectively. At least one of the flexure hinges 120 a , 120 b , and 120 c is further coupled to a tab (also referred to herein as a member) 130 a , 130 b , and 130 c . In a desirable embodiment, each of three flexure hinges 120 a , 120 b , and 120 c is coupled to a mutually distinct lab 130 a , 130 b , and 130 c . Tabs 130 a , 130 b , and 130 c typically extend radially outward along radial axes 132 a , 132 b , and 132 c that typically pass through the center point 114 of the inner stage 110 . Axes 132 a , 132 b , and 132 c are fixed relative to support member(s) 150 . with their position(s) being unchanged by actuation of the tabs 130 a , 130 b , and 130 c . The tabs 130 a , 130 b , and 130 c effectively function as lever arms and are coupled to at least one support beam 140 at at least one of fulcrum points 134 a , 134 b , and 134 c about which they pivot. The term “fulcrum ” is used herein in a manner consistent with the conventional dictionary definition. i.e., a pivot point about which a lever arm operates (Academic Press Dictionary of Science and Technology, 1992). Actuation of tabs 130 a , 130 b , and 130 c is discussed in more detail hereinbelow.
The support beams 140 may be configured in substantially any manner. For example, in compliant mechanism 100 the support beams are configured in a substantially equilateral triangular pattern rotated about 180 degrees (i.e., half a turn) out of phase with the triangular inner stage 110 . Support beams 140 may further be coupled to at least one support member 150 , for example at the corners 142 of the triangular pattern of support beams 140 . Support member(s) 150 are typically adapted to provide for mounting the compliant mechanism 100 to another structure. For example, compliant mechanism 100 includes a support member 150 in the form of an outer support ring (i.e., a circular portion that encloses and supports the other portions of the compliant mechanism) that includes a plurality of holes 152 configured for fastening (e.g., screwing) the compliant mechanism to another fixture. As described in more detail hereinbelow, actuation of tabs 130 a, 130 b, and 130 c causes relative movement of the inner stage 110 with respect to support member(s) 150 .
Referring now to FIGS. 2 and 3 two alternate embodiments 100 ′ and 100 ″ of the compliant mechanism of this invention are illustrated. Compliant mechanisms 100 ′ and 100 ″ are similar to that of compliant mechanism 100 in that each includes an inner stage 110 ′, 110 ″ coupled to a plurality of flexure hinges 120 a ′, 120 b ′, 120 c ′, and 120 a ″, 120 b ″, 120 c ″, respectively, which are further coupled to one or more tabs 130 a ′, 130 b ′, 130 c ′, and 130 a ″, 130 b ″, 130 c ″, respectively, which are still further coupled to support beams 140 ′, and 140 ″, respectively, at fulcrum points 134 a, 134 b, and 134 c.
Compliant mechanism 100 ′ includes a substantially circular inner stage 110 ′, as opposed to the substantially triangular inner stage 110 of compliant mechanism 100 . Further, support beams 140 ′ are configured in a substantially circular pattern about the circular inner stage 110 ′. Compliant mechanism 100 ′ further differs from compliant mechanism 100 in that it includes a plurality (e.g., three) of support members 150 ′ coupled to support beams 140 ′. Each of the support members 150 ′ is typically in the form of a disk, having a central hole 152 ′ for fastening the compliant mechanism 100 ′ to another structure. Support members 150 ′ are typically spaced to form a triangular (e.g., a substantially equilateral triangular) pattern in order to provide balanced support and stiffness.
Compliant mechanism 100 ″ is further similar to that of compliant mechanism 100 in that it includes a substantially equilateral triangular inner stage 110 oriented about 180 degrees (i.e., half a turn) out of phase with a substantially triangular configuration of support beams 140 ″. Support beams 140 ″ are typically coupled to three support members 150 ″ at the corners of the triangular configuration thereof. Support members 150 ″ typically include a plurality of holes 152 ″ for fastening the compliant mechanism 100 ″ to another structure. Support members 150 ″ further include constraining compliant mechanisms 156 , which allow for a relatively high degree of relative movement between the inner stage 110 ″ and support members 150 ″ (as compared to compliant mechanisms 100 and 100 ′) without requiring plastic deformation of the compliant mechanism's components. The thickness of support beams 140 ″ may optionally be reduced proximate the tabs 130 a ″, 130 b ″, 130 c ″ and support members 150 ″, to reduce their stiffness and thus facilitate their plastic deformation.
The tabs may further optionally include other features, such as but not limited to, holes, slots, grooves, protrusions, detents, and the like for interfacing with an actuator, such as actuator 162 of FIG. 4 a. For example, the protrusions 163 in compliant mechanism 100 ″ provide a feature against which an actuator may press. Rounded features may be used in some applications to ensure that the actuator engages the tab 130 a ″, 130 b ″, 130 c ″ at a predetermined distance from the fulcrum point 134 a, 134 b, 134 c, and is properly oriented to operate in a predetermined direction.
Referring now to FIGS. 4 a and 4 b, the relative movement of inner stage 110 with respect to support member 150 is discussed in more detail. The artisan of ordinary skill will readily recognize that while the following discussion pertains to compliant mechanism 100 in particular, the same general principles apply to compliant mechanisms 100 ′ and 100 ″ regarding movement of inner stages 110 ′ and 110 ″ with respect to support members 150 ′ and 150 ″, respectively. The compliant mechanism paradigm described herein effectively utilizes the concept of offsetting (i.e., moving) at least one of the corners of a triangle (e.g., hinge points 122 a, 122 b, and 122 c ) from the axes 132 a, 132 b, and 132 c. This may be thought of, and treated mathematically, as being analogous to offsetting the shaft axis of rotation from the plane of symmetry of the groove of one embodiment of the adjustable kinematic coupling disclosed in the above referenced '562 patent application. The compliant mechanism 100 shown in FIGS. 4 a and 4 b is substantially identical to that of FIG. 1 with the exception that in FIG. 4 b, tab 130 a has been actuated to the left (i.e., the negative x direction) a distance Δx. The hinge point 122 a, originally at position M 1 ( FIG. 4 a ), is moved a perpendicular distance x from the axis 132 a to position A 1 ( FIG. 4 b ). The two non-actuated tabs (tabs 130 b and 130 c ) are constrained by their respective support beams 140 to move parallel to axes 132 b and 130 c, respectively. To maintain geometric congruence after actuation of tab 130 a, tabs 130 b and 130 c displace along axes 132 b and 132 c, respectively, resulting in the movement of hinge points 122 b and 122 c from points M 2 and M 3 to A 2 and A 3 , respectively. The exemplary actuation shown in FIGS. 4 a and 4 b results in a displacement of the inner stage 110 , with respect to the support member 150 , in the x and θ z directions.
Moreover, although in the example shown only element 130 a has been actuated, tabs 130 b and 130 c may also be actuated separately or jointly to affect the relative positions of the inner stage 110 and support member 150 in a controlled and mathematically predictable manner. For example, as shown in FIG. 5 a, actuation of tabs 130 b and 130 c with an equal magnitude (shown as Δ′) in opposite directions about axis 114 results in a displacement of the inner stage 110 with respect to the support member 150 in the y direction. In an alternate example, shown in FIG. 5 b, actuation of tabs 130 a, 130 b, and 130 c with an equal magnitude (shown as Δ″) in the same direction about axis 114 results in a displacement of the inner stage 110 with respect to the support member 150 in the negative θ z direction.
The examples shown in FIGS. 4 a, 4 b, 5 a, and 5 b illustrate actuation of tabs 130 a, 130 b, and 130 c effecting in-plane (i.e., x, y, and θ z ) relative movement between the inner stage 110 and support member 150 . However, tabs 130 a, 130 b, and 130 c may also be actuated in an out-of-plane (i.e., z) direction. Such actuation serves to effect out of plane (i.e., θ x , θ y , and z) relative movement between the inner stage 110 and support member 150 . For example, actuation of tabs 130 a, 130 b, and 130 c with an equal magnitude in the negative z direction (i.e., into the page in FIG. 5 a or 5 b ) typically results in a displacement of the inner stage 100 with respect to the support member 150 in the positive z direction (i.e., out of the page). However, depending on the geometry and orientation of the tabs, support beams, and hinges, this motion may be in the positive or negative direction. Further, a combination of in plane and out of plane actuation of the tabs 130 a, 130 b, and 130 c enables controlled relative movement in all six degrees of freedom, i.e., in the x, y, z, θ x , θ y , and θ z directions.
One advantage of various embodiments (e.g., compliant mechanisms 100 , 100 ′, and 100 ″) of the present invention is that they may be fabricated to include a relatively wide range of predetermined displacement ratios. As set forth hereinabove, the displacement ratio is defined as the ratio of actuator input motion to the relative motion between the inner stage 110 and the support member 150 . For example, for applications requiring relatively small-scale (e.g., nanometer and sub-nanometer range) accuracy and precision, a compliant mechanism having a relatively large displacement ratio, enabling relatively small relative movements, may be desirable. A compliant mechanism having a relatively large displacement ratio may be fabricated by increasing the length 138 ( FIG. 4 a ) of the tab relative to the distance between the hinge and flexure points (e.g., the distance between hinge point 122 a and fulcrum point 134 a in FIG. 2 a ) and/or the compliance of the tab. Alternatively, for applications in which a wider range of relative motion is required (e.g., on the order of millimeters or more), a compliant mechanism having a relatively small displacement ratio may be desirable. A compliant mechanism having a relatively small displacement ratio may be fabricated by decreasing the length of the tab 138 relative to the distance between the hinge and flexure points. For typical applications it may be desirable for the compliant mechanisms of this invention to include a displacement ratio in the range from about 0.1 to about 1000. For some particular applications it may be desirable for the compliant mechanisms of this invention to include a displacement ratio in a range of about 2 to about 20.
In alternative embodiments, the inventive compliant mechanism may be used, as stated hereinabove, in the precision alignment of a relatively wide range of product components, fixtures and the like. In some applications, the flexure hinges (e.g., flexure hinges 120 a, 120 b, and 120 c in FIG. 1 ) may be spaced to form triangles that are not substantially equilateral. This may be beneficial in that it renders motion control in a predetermined direction more or less sensitive to actuator input. Further, the need to use non-equilateral geometry may arise in applications in which the structure of various components does not permit equilateral spacing.
The compliant mechanisms of this invention may be fabricated from substantially any material. Prototypes have been fabricated using metallic materials, such as aluminum alloy 6061, using an abrasive water jet cutting tool. Metallic compliant mechanisms may be advantageous in that they may provide for both elastic and plastic deformation of the mechanism's components. It is further envisioned that the compliant mechanisms of this invention may be fabricated from other materials, such as silicon or doped silicon wafers, using a technique such as deep reactive ion etching (DRIE). DRIE fabrication may be advantageous in that relatively small compliant mechanisms may be formed (e.g., having a characteristic diameter as small or even smaller than 2500 microns).
The artisan of ordinary skill will readily recognize that there are many variable shapes and configurations for the various portions (i.e., the inner stage, the hinge portion, the tabs, the support beams, and the support members) of the compliant mechanism of this invention that may be used to alter the repeatability, resolution, displacement ratio, and position control capabilities of the compliant mechanism.
The modifications to the various aspects of the present invention described hereinabove are merely exemplary. Other variations, modifications, and other implementations of what is described herein will also occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the invention is to be defined not just by the preceding illustrative description, but instead by the spirit and scope of the following claims. | A compliant mechanism is provided for accurate and precision alignment of mechanical component parts, surfaces or assemblies and the like, where low-cost, accurate, and repeatable alignment are desired. The compliant mechanism may be used in applications that require high precision alignment and where the relative location of coupled components must be variable or adjustable. The compliant mechanism includes a stage coupled to a plurality of hinges, at least one tab coupled to one of the hinges, and a support coupled to the tab. The relative position of the stage and the support may be adjusted by actuating (i.e., displacing) the tab(s) or other parts of the structure, to enable controlled movement in six degrees of freedom therebetween. | 8 |
[0001] This is related to U.S. Provisional Patent application Ser. No. 60/178,552, filed Jan. 26, 2000. The benefit of the filing date of that application is hereby claimed.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates to novel accessories for archery bows and, more particularly, to such accessories which are capable of significantly reducing both bow jump and the noise made when an arrow is released.
BACKGROUND OF THE INVENTION
[0003] U.S. patent application Ser. Nos. 09/478,921, filed Jan. 6, 2000 and 09/466,512, filed Dec. 17, 1999 disclose archery bow accessories respectively identified in the commercial world by the names LIMB SAVER™ and STRING LEECH™.
[0004] A LIMB SAVER™ is an accessory that can be attached to the limbs of a bow and/or to the outer end of the stabilizer of a bow equipped with an accessory of that character to reduce the adverse effect of the vibrations set up in the bow when an arrow is released.
[0005] A STRING LEECH™ is designed to reduce the noise generated when an arrow is released. Devices with this objective are known in the trade as string silencers.
[0006] One type of STRING LEECH™ string silencer is knotted onto a bowstring, one at each end of the string. A second type of STRING LEECH™ is installed between two parts of a split bowstring and retained in place by complementary elements of the silencer.
SUMMARY OF THE INVENTION
[0007] There have now been invented and disclosed herein certain new and novel archery bow accessories which are also designed to reduce the noise made when an arrow is released and, in addition, to significantly reduce bow jump caused by release of the arrow. These shock absorbing accessories are attached to the riser of the bow. They can be used alone or in combination with LIMB SAVER™ and STRING LEECH™ accessories and/or in combination with other devices designated to attenuate the adverse effect on accuracy attributable to bow jump and noise when an arrow is released.
[0008] An accessory employing the principles of the present invention is attached to the riser of a bow, typically using the drilled and tapped hole provided for a conventional bow stabilizer.
[0009] The novel shock absorbing accessories disclosed herein are made up of a rigid transfer rod or transfer rod assembly, a viseo-elastic shock absorbing component, and a compression ring. When an arrow is released, vibrations set up in the bow are transferred to the riser with the transfer rod (or assembly) directing vibrations from the riser to the shock absorbing component of the accessory. The shock absorbing material reduces the time for which vibrations of a character that might effect accuracy are felt by the user. Also, the shock absorbing material causes maximum energy to be transferred to the arrow being released.
[0010] The shock absorbing component of the accessory is very effective, in part because it is preloaded as the accessory is assembled. The compression ring keeps the shock absorbing component in its compressed, preloaded state.
[0011] Shock absorber accessories as disclosed herein work well both with double cam bows—where the entire bow tends to jump forward when an arrow is released—and single cam bows—where the bottom of the bow tends to kick forward and upward on arrow release.
[0012] Accessories as disclosed herein are also relatively light, which is another significant advantage of these products.
[0013] The performance of a bow equipped with an accessory as disclosed herein can be enhanced by attaching a bow stabilizer or a vibration pattern modifier of the character disclosed in co-pending application Ser. No. 09/478,921 to the accessory.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1 is a pictorial illustration of a compound bow equipped with a shock absorbing accessory embodying the principles of the present invention and provided to reduce bow jump and noise when an arrow is released;
[0015] [0015]FIG. 2 is a perspective view of the shock absorbing accessory;
[0016] [0016]FIG. 3 is an exploded view of the shock absorbing accessory;
[0017] [0017]FIG. 4 is a view similar to FIG. 3 but with a shock absorbing component of the accessory shown in section taken substantially along line 4 - 4 of FIG. 2;
[0018] [0018]FIG. 5 is a graph showing the shock imparted to a representative compound bow when an arrow is released; and
[0019] [0019]FIG. 6 shows how the shock is reduced when the bow is fitted with a shock absorbing accessory as shown in FIGS. 1 - 4 .
DETAILED DESCRIPTION OF THE INVENTION
[0020] Referring now to the drawings, FIG. 1 depicts a compound bow 20 equipped with a vibration decay pattern modifying, shock absorber 22 embodying the principles of the present invention. Bow 20 has flexible limbs 24 and 26 mounted to the opposite ends of riser 28 and bow string 30 . The bow string is strung around cams 32 and 34 at the ends of limbs 24 and 26 with the ends of the bow string being anchored to shafts 36 and 38 which rotatably support cams 32 and 34 from the limbs 24 and 26 of bow 20 .
[0021] As is best shown in FIGS. 2 - 4 , the vibration decay modifying accessory 22 has a unit 40 made up of elastomeric decay pattern modifying, elastomeric component 42 surrounded by a compression ring 44 ; a flanged tube 46 with integrated internal threads 90 , and a flanged vibration transfer component 48 with integrated, externally threaded elements 50 and 52 at its opposite ends.
[0022] Referring now primarily to FIGS. 3 and 4, the elastomeric component 42 of unit 40 has a circular profile (see FIG. 2). The major elements of component 42 are a head 54 and an integral, depending stem 56 with straight and beveled conical profile elements 58 and 60 . The head 54 of component 42 has a vertical edge 63 between two, integral, tapered edges 62 and 64 . The lower part of head 54 constitutes a skirt 66 with an inner edge 68 which is concentrically spaced about the lower part of head 54 and its inner edge 70 . This leaves a gap 72 between the head 54 and stem 56 of component 54 , which allows decay pattern modifying movement of head 54 relative to stem 56 .
[0023] Decay pattern modifying movement of head 54 is further promoted by concentric, inverted pyramid grooves 74 and 76 in the upper part 62 of head 54 and by pockets or recesses which are equiangularly spaced around the periphery of integral stem element 56 . These pockets, all identified by reference character 77 (see FIG. 3) for the sake of convenience, have closed inner ends and open onto the groove 72 between head and stem components 54 and 56 .
[0024] The stem 56 of decay pattern modifying, elastomeric component 42 can vibrate or oscillate in directions generally normal to the longitudinal axis 78 of accessory 22 in any and all directions around the circumference of the transfer component 48 . At the same time, head 54 of the component 42 can oscillate laterally and vertically (with that component oriented as shown in FIG. 4), and the edge portion 63 can also oscillate around the circumference of the head in directions generally paralleling axis 78 .
[0025] The effectiveness of accessory 22 is promoted by preloading the elastomeric component 42 of the accessory. Preloading is accomplished by first installing the elastomeric component 42 in ring 44 , which generally spans the edge element 63 of head 54 . Next, flanged component 46 is installed in a central bore 80 extending from top to bottom through elastomeric component 42 with a tubular element 82 of component 46 located in, and extending from the top to the bottom of component 42 and with a flange 84 of component 46 butting the top edge 86 of the elastomeric component 42 . Next, the externally threaded element 50 of vibration transfer component 48 is threaded into the tubular element 82 of component 46 , the external threads 88 on element 50 engaging the complimentary internal threads 90 in tubular element 82 and drawing components 46 and 48 together until the flange 92 on component 48 engages, and presses against, the bottom edge 94 of elastomeric component stem 56 , squeezing elastomeric component 42 in a vertical direction. This action generates a laterally extending force which is maintained in element 42 by the tubular element 82 of component 46 and compression ring 44 , which keep component 42 from expanding inwardly or outwardly by effective “squeezing.”
[0026] The rotation of component 48 in sleeve 82 is continued until the flange 92 of component 48 engages the lower end 96 of tubular element 82 . As best shown in FIG. 4, this end 96 is spaced from the bottom 94 of elastomeric component stem 56 . The load applied to elastomeric component 42 can be provided at a selected level by adjusting this spacing.
[0027] Accessory 22 is, in the illustrated, exemplary application of the invention, mounted to the riser 28 of bow 20 by threading element 52 of accessory component 48 into a drilled and tapped, blind aperture 97 in the riser until the bottom or lower edge 98 of the accessory component element 48 is seated on, and frictionally engaged with, the front edge 100 of riser 28 .
[0028] [0028]FIGS. 5 and 6 compare the decay pattern of a bow such as the one illustrated in FIG. 1 without an accessory as disclosed herein (FIG. 5) with the decay pattern for the same bow equipped with an accessory of the character identified by reference character 22 . It will be apparent to the reader that accessory 22 significantly shortens the decay time of the vibrations set up in the bow when an arrow is released, especially those larger and consequently more deleterious vibrations. The result is a significant advantage. The practical result, as discussed above, is a marked reduction both in bow jump when an arrow is released and the noise generated when that action occurs.
[0029] The shock absorbing elastomeric component 42 (see FIG. 4) of the present invention is preferably fabricated from a soft, viseo-elastic material with a Shore A hardness in the range of 3 to 20.
[0030] One suitable viseo-elastic material is NAVCOM™. NAVCOM™ is a soft, amorphous, rubber-like material which contains a mixture of chloroprene and butyl polymers and has the following physical properties (representative).
Shore A hardness: 17-90 Ultimate Tensile Shore Elongation Strength Compression Specific Environment A (Percent) (PSI) Set (Percent) Gravity 7 1,075 373 6.01 1.014 12 900 643 7.3 1.025 20 835 1,069 6.9 1.063 30 1,056 1,621 4.0 1.074 40 326 1,453 N/A 1.185 90 175 2,440 N/A 1.379 Oven aged 7 N/A N/A 56.3 — for 12 — — 31.1 — 70 hrs at 20 — — 30.8 — 212 ± 5° F. 40 — — 22.4 — 90 — — 18.6 —
[0031] [0031] At room temperature - Medium Resilience: At high temperature - Fairly high Heat resistance Good Outdoor aging resistance: Excellent Low temp flexibility: Good Abrasion resistance: Good Flex life: Good Solvent resistance: Hydrocarbons - Fair to good Oxygenated - Fair to good Air permeability: Low to moderate Moisture resistance: Fair Useful operating temperature: −40° to 250° F.
[0032] While the invention is described and illustrated here in the context of a preferred embodiment, the invention may be embodied in many forms without departing from the spirit or the essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive. The scope of the invention is indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein. | An accessory for modifying the decay pattern of vibrations set up in an implement to which the accessory is attached, and the combination of a decay pattern modifying accessory and an implement. Methods of manufacturing decay pattern modifying accessories are also disclosed. | 5 |
BACKGROUND OF THE INVENTION
[0001] Testing software is often used to improve the quality of a software program (subject software). In a software based testing environment, software defects and errors may be identified and isolated by the use of testing software to test the subject software.
[0002] Diagnostic testing software, for example, is a form of testing software. Diagnostic testing software may be used to identify subject software failures and provide an engineer with information to help isolate and repair problems. The diagnostic testing software may be used to detect a problem in subject software that causes a failure during software development. Using diagnostic testing software, defects may be found that would allow the engineer to repair subject software at a module level. Diagnostic testing software helps the engineer to isolate a problem and to determine what caused the failure so that the system may be repaired.
[0003] Diagnostic testing software may include a set of sub-tests that are run in a predetermined sequence. In diagnostic testing, the sub-tests may be initially run to test small portions of a system. The test coverage of the diagnostic testing software is then gradually increased until the entire system is tested. The test sequence helps isolate errors at lower levels of subject software so that the cause of the errors may be understood. However, engineer intervention is often required to help the diagnostic test progress.
[0004] Verification testing software is another form of testing software. Verification testing software is used to determine if subject software is either defective or good. Verification software detects defects so that if subject software passes a defects test, the system should be good. If defects are found, then diagnostic software can be used to identify the causes. An example of a verification software test is a test until failure test. Repetitively subjecting subject software to testing using the same test helps engineers determine whether the subject software will withstand the different demands a user may put on the software.
[0005] A typical test environment includes a platform to be tested and an engineer who conducts the testing. The engineer designs a test plan, i.e., a set of tests, which takes into account the different aspects of a system to be tested and tests the system according to the tests generated. Tests are planned and supervised by the engineer, but when a problem arises using conventional testing methods as described above, conventional testing software merely reports that a problem has occurred and typically stops a test in progress to alert the engineer.
SUMMARY OF THE INVENTION
[0006] At least one embodiment of the invention is directed to a method for testing software. Such a method may include: receiving a plurality of test-modules associated with an external system and organized into a sequence, each test-module including a software testing-inquiry that generates a plurality of intermediate results, the test module returning a distilled result based upon the results, receiving one or more rules to which at least one of the test-modules in the sequence is subject, application of each rule having one or more outcomes, at least one outcome for each rule being the determination of the next test-module to be administered, each rule including one or more actions conditioned upon the distilled result returned by the corresponding test module, the one or more conditioned actions being configurable to be a branch out of the sequence to a predetermined test-module; administering the sequence of test-modules sequentially except where a branch is invoked to administer the sequence from another point in the sequence, the administering of a current test-module including executing the current test-module, the executing including sending signal bits to the external system, and applying, if the current test-module is subject to one or more rules, such one or more rules.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1A is an example of a block diagram of an automated testing system according to an embodiment of the invention;
[0008] FIG. 1B is an example logical structure of a template according to an embodiment of the invention;
[0009] FIG. 2 is an example of a flow diagram of creating a test sequence according to an embodiment of the invention;
[0010] FIG. 3 is an example of a flow diagram of test sequence processing according to an embodiment of the invention;
[0011] FIG. 4 is an example of a flow diagram of processing an action according to an embodiment of the invention; and
[0012] FIG. 5 is an example of a screen shot of a graphical user interface for creating a test sequence according to an embodiment of the invention.
[0013] Additional features and advantages of the invention will be more fully apparent from the following detailed description of example embodiments, the appended claims and the accompanying drawings.
DETAILED DESCRIPTION OF EMBODIMENTS
[0014] An embodiment of the invention, at least in part, is the recognition of the following. Systems for testing software, according to the background art, run in lock-step to a test sequence, independent of test results. They are essentially dumb systems for testing software. A batch of software tests are run against subject software and data is collected. The sequence of execution is not a function of test results. Thus, a problem with such testing is that an engineer must comb through test results that may be too numerous to determine a problem with the subject software and what test to perform next based on the test results. Depending on the volume of test results, the task of analyzing test results and setting up new tests could be daunting. Moreover, testing with extensive engineering interaction can be very costly and inefficient using such testing technology.
[0015] An embodiment of the invention permits an engineer or a user in need of test results to run numerous test-modules without user intervention or at least a significantly lessened amount of user intervention.
[0000] Automated Testing System 100
[0016] FIG. 1A is an example of a block diagram of an automated testing system 100 according to an embodiment of the invention. The automated testing system 100 may be used to run numerous test-modules against a subject system 160 without user intervention or at least a significantly lessened amount of user intervention. The automated testing system 100 includes: an engineer platform 110 ; a test management system 120 ; source code control database 130 ; results database 140 ; test engine platform 150 ; and the subject system 160 . The subject system 160 is shown as part of the automated testing system 100 , but may be a system separate from the automated testing system 100 .
[0017] The engineer platform 110 may be a personal computer (PC) or other terminating system by which an engineer, or other user associated with running test-modules against the subject system 160 , can retrieve test-modules from the source control database 130 , arrange the test-modules into a test-sequence, and receive associated test results. More detail of the user interface is later described in the discussion of FIG. 5 . The engineer platform 110 may be connected directly or indirectly to the test management system 120 .
[0018] The engineer platform 110 receives from the test management system 120 a list of available test-modules that may be applied to the subject system 160 and presents them to the user via a graphical user interface. The engineer platform 110 further provides the user with the results of test-modules and their related software-targeted testing-inquires of the subject system 160 . The engineer platform 110 , additionally, receives test-module sequence information associated with the subject system 160 from the user and sends it to the test management system 120 .
[0019] The test management system 120 may be a PC, a plurality of computers, or other computing device that can host software to provide input/output capabilities. Such input/output capabilities can include web server capability, Email server capability (or other communications capability such as paging, calling, and the like), and provide access to a source control database 130 and results database 140 . The test management system 120 may be connected directly or indirectly to the engineer platform 110 , the source control database 130 , the results database 140 , and the test engine platform 150 . The test management system 120 provides a majority of the processing for the automated testing system 100 .
[0020] The test management system 120 receives from the source control database 130 available test-modules associated with the subject system 160 and sends a list of available test-modules to the engineer platform 110 . The test management system 120 may further receive test-module sequence information from the engineer platform 110 , process it, and send testing information to the test engine platform 150 . The test management system 120 also may receive test-module results or software-targeted testing-inquiry results from the test engine platform 150 , process the results, store the results in the results database 140 and send test-module results or software-targeted testing-inquiry results to the engineer platform 110 by Email or by other media such as a pager system, telephone system, and the like.
[0021] The source control database 130 may be any database such as a Oracle, IBM DB2, or Lotus Notes database residing on a PC, workstation, server system, or the like. The source control database may be connected to the test management system 120 . Further, the source control database 130 , may be accessed locally or remotely for receiving templates including test-modules from engineers.
[0022] The source control database 130 is originally populated by engineers using templates that include test-modules. The test-modules include mappings of possible software-targeted testing-inquiry results of the subject system 160 to states such as PASS, FAIL, or WARNING. The source control database 130 stores and provides the test-modules that are available to the test management system 120 .
[0023] The results database 140 may be any database such as an Oracle, IBM DB2, or Lotus Notes database residing on a PC, workstation, server system, or the like. The results database 140 may be connected to the test management system 120 .
[0024] The results database 130 stores log files and results from the test-modules applied to the subject system 160 . The results database 130 receives test-module result information from the test management system 120 .
[0025] The test engine platform 150 may be a PC or like system that performs testing-inquiries on the subject system 160 and provides an interface to the subject system 160 . The test engine platform 150 may be connected directly or indirectly to the test management system 120 .
[0026] The test engine platform 150 receives testing information from the test management system 120 and administers test-modules on the subject system 160 . At least one of the test-module results or software-targeted testing-inquiry results are received from the subject system 160 are processed and sent to the test management system 120 from the test engine platform 150 . In so doing, the test engine platform 150 administers a sequence of test-modules sequentially except where a branch is invoked to administer the sequence from another point in the sequence. The administering of a current test-module includes executing the current test-module and applying, if the current test-module is subject to one or more rules, such one or more rules.
[0027] The subject system 160 may be a system including subject software, hardware system, or any type of system that needs testing. For example, the subject system 160 may include subject software. The subject system 160 receives testing-inquiries from the test engine platform 150 in the form of signal bits, executes the software-targeted testing-inquiry, and sends the software-targeted testing-inquiry results to the test management system 120 and test engine platform 150 .
[0028] While the engineer platform 110 , source control database 130 , test management system 120 , results database 140 , and test engine platform 150 are shown as being separate elements, they may be combined in various configurations to be part of one or more platform. Moreover, the databases 130 , 140 may be part of one database on one machine.
[0000] Template Creation
[0029] Prior to using the automated testing system 100 , engineers plan and create templates that include at least one test module as shown in FIG. 1B . FIG. 1B shows an example logical structure of a template according to an embodiment of the invention. Template 10 may include one or more test-modules 12 . The template 10 is generated by a test-engineer and is stored in the source control database 130 .
[0030] The test-module 12 includes multiple software-targeted testing-inquiries 14 . The test-module 12 may be created using Silk™, PERL, a combination thereof, or any other tool that may be used to aid in the processing of results from the software-targeted testing-inquiries 14 . When a test-module 12 is administered by the automated testing system 100 , the returned value is a distilled result which is later described.
[0031] The software-targeted testing-inquiries 14 are individual tests used by the test engine platform 150 to query the subject system 160 . Each software-targeted testing-inquiry 14 may be part of or one of an integration test, functional test, system test, combination thereof, and any other like tests as are known in the art used to test software. The test engine platform 150 executes the software-targeted testing-inquiry 14 which causes signal bits to be sent to subject software running on the subject system 160 . The signal bits can be used to determine whether the subject system 160 satisfies any of the conditions associated with a particular software-targeted testing-inquiry 14 .
[0032] In creating a test-module 12 for use in an embodiment of the invention, an engineer also maps the possible software-targeted testing-inquiry 14 results of the test-module to a cumulative value known as a distilled result. The distilled result reflects the cumulative results of the software-targeted testing-inquiries 14 when the test-module 12 is administered and is also the output of the test-module 12 .
[0000] Associating Test-Modules with Rule Sets
[0033] After templates are created and loaded into the source control database 130 , they are then available for manipulation and sequencing by a user. A user (e.g., engineer) may create a test-module sequence from a list of available test-modules 12 included in one or more templates. Using a graphical user interface, later discussed in the explanation of FIG. 5 , the user may select test-modules 12 from a list of available test-modules 12 in the database, place the test-modules 12 into a sequence for execution, and associate a rule set for each test-module 12 selected.
[0034] Rule sets are conditional constructs associated by a user to a test-module's 12 possible distilled results and include at least one or more rule. Each rule includes a condition associated with one of the test-module's 12 distilled results, and one or more actions. The conditions of the rule set may be provided to the user when a test module is selected. Alternatively, the user may already know which possible distilled results have been associated by an engineer when creating the test-module 12 . In this case, the user may create conditions that address each of the distilled results for a particular test-module 12 . The condition is used in determining what action to take based on a particular distilled result from an administered test-module 12 . The distilled result in this context acts as a trigger to invoke the action.
[0035] An example rule set for an example test-module A may take the following logical form:
Rule 1: If test module A's distilled result is PASS, then continue to the next test module. Rule 2: If test module A's distilled result is FAIL, then Email tester1. Rule 3: test module A's distilled result is WARNING, then Email tester2.
[0039] In the above example, Rules 1, 2, and 3 make up the rule set. With regard to Rule 1, the condition is: test module A's distilled result is a PASS. Here, the distilled result that acts a trigger for Rule 1 is the distilled result of PASS. The action of Rule 1 is to continue to the next test-module.
[0040] The action may be a command to send a communication, abort an operation, skip the next test-module in sequence, repeat the current test-module, execute a particular test-module, execute a shell script, etc. Moreover, the conditions and associated actions may be nested. For example a rule may logically take a form that if a test-module passes, another test-module is administered. This is so since one or more actions associated with a condition may be configurable to be a branch out of a sequence to a predetermined test-module.
[0041] Accordingly, when the test-module 12 is administered and a distilled result of the test-module 12 is PASS, the condition of Rule 1 is satisfied. The distilled result of PASS triggers the automated testing system 100 to continue to the next test-module 12 as per Rule 1. Similar activity occurs if the distilled result of the test-module is a FAIL or WARNING according to Rules 2 and 3, respectively.
[0042] In addition to the above example, rule sets may include actions that adaptively adjust the test-module 12 sequence. For example, a rule may include an action to repeat a test-module 12 until distilled results representing a PASS state are returned from the test-module 12 . The ability to alter the sequence is a valuable tool that additionally helps enable testers to automate much of their activities and perform complex test executions and test groupings that are otherwise too costly or complex for human implementation.
[0043] To restate, test-modules 12 include software-targeted testing-inquiries 14 that, when invoked, act on the subject system 160 . A rule set is associated with a test-module 12 . A rule in a rule set may include at least one condition and one action associated with the test-module's 12 distilled result. A test-module is implemented using at least one software-targeted testing-inquiry 14 , while a rule associates a test-module's 12 distilled result with a condition and an action. An engineer designs the software-targeted testing-inquiries 14 and incorporates them into test-modules 12 for submission into the source control database 130 via a template. A user, subsequently, selects test-modules 12 from the source control database 130 , places them into an execution sequence and associates a rule set to the test-modules 12 using the engineer platform 110 .
[0044] While the above example describes a rule associated with a test-module 12 , not every test-module 12 needs to be associated with a rule when placed by the user into a test sequence.
[0045] To adjust to different environments, the engineers may create test-modules suitable for the particular environment and the test engine platform 150 may be configured to provide an interface to the subject system. Embodiments of the invention are described in terms of use in an environment for testing software. However, the invention may also be used in a hardware testing environment where hardware is the subject of testing.
[0046] FIG. 2 is an example of a flow diagram of creating a test-module sequence according to another embodiment of the invention. The creation of a test-module sequence is an interaction between the automated testing system 100 and the user. The user may use the engineer platform 110 to interact with the automated testing system. The create test-module sequence process is initialized at block 210 . Initialization may include logging in a user to an account. The user may then input database connection information at block 220 , and later specify a test engine at block 270 , or input an Email address at block 275 .
[0047] At block 220 , the user may input database connection information into the engineer platform 110 . This may include the designation of a database and database-secure logon information. The user is then connected to the source control database 130 via the engineer platform 110 and test management system 120 at block 230 . The interaction of the user may include presenting to the user a graphical user interface, e.g., corresponding to the screen-shot of FIG. 5 , to facilitate creating a test-module sequence. Available representations of test-modules 12 may then be retrieved from the source control database 130 and be used to populate an engineer platform 110 screen, block 240 , from which the user may select the available test-modules 12 to be used when testing the subject system 160 . As previously described, the test-modules 12 are made available by an engineer that has previously entered them into the source control database 130 via a template 10 that includes the test-modules 12 . After the screen has been populated with a list of available test-modules 12 , the user may then select the test-modules 12 to create a test-module sequence, block 250 , to be used in testing the subject system 160 . The create sequence process then continues by placing the selected available test-modules information into a test sequence display, block 255 , on the user's screen.
[0048] A default rule set may be added to the test sequence display at block 260 . Examples of default rules may include: 1) if the result of a test-module is a PASS, then send an Email to a mailing list; 2) if the result of a test-module is a WARNING, send an Email to those on a second mailing list; and 3) if the result of a test-module is a FAIL, then send an Email to those on a third mailing list. After the test-module sequence display is populated, the user may then edit the test-module sequence and rule sets therein at block 265 .
[0049] At block 270 , the user may specify a particular test engine platform 150 to be used for testing the subject system 160 . Additionally, the user may input a mail group, block 275 , designating which Email group or lists recipients may be pulled from. A mail group may be a list of Email addresses or address lists. While in this example Email addresses are used, pager addresses, telephone numbers, or the like may also be used.
[0050] At block 280 , a test-module sequence file is created by the test management system 120 , including the test engine information and mail group information. Also included in the test-module sequence file may be a user designation of where a test may be found and the automation software to be used by the test-module. The test management system 120 may then create a parsing rule file for parsing rule sets at block 285 . Control data files containing control information are then packaged by the test management system 120 at block 290 . Further, at block 295 , testing information in the form of a test-module sequence package including the package of control data files and the test-module sequence file are sent to the test engine platform 150 at block 295 where it is processed. After a test definitions file is sent in block 295 , the create test-module sequence process is then finished at block 297 . The processing of the test definition package is shown in FIG. 3 .
[0051] FIG. 3 is an example of a flow diagram of test-module sequence processing according to another embodiment of the invention.
[0052] The test-module sequence process is executed by the test engine platform 150 . It details the processing of a sequence by the test engine platform 150 . At block 305 , the test engine platform 150 waits for a test-module sequence package from the test management system 120 . Once received, the test-module sequence package is opened at block 310 . A parsing tree is then created at block 330 from the parsing rule file created at block 285 for use in processing test results from the subject system 160 . After the parsing tree is created, a test-list is created at action 340 from the test sequence file of block 280 and each test-module is assigned an ID. The test-module list includes a list of test-modules with IDs to be run on the subject system 160 .
[0053] At block 350 , a first test is selected from the test-list on the basis of test-module ID to be executed. The test-module is then executed on the subject system 160 at block 360 . The test engine platform 150 passes testing-inquiries to the subject system 160 as part of the test-module execution process. During execution of the test-module, software-targeted testing-inquiry results are received by the test engine platform 150 from the subject system 160 .
[0054] The software-targeted testing-inquiry results are parsed at block 370 using the parse tree created in block 330 . During the parsing process, processed software-targeted testing-inquiry results and test-module results are sent to the test management system 120 which further processes them and stores them in the results database 140 where a log of the software-targeted testing-inquiry results and test-module results is kept. As part of the parsing process the following can occur: nested software-targeted testing-inquiries are processed and identified, a hierarchy of errors may be determined among the software-targeted testing-inquiries, software-targeted testing-inquiry results are examined to see if a condition has been triggered, and/or result log files may be created. Where a result log file is created, it may also be time stamped.
[0055] If a condition is triggered, the parser notes this and executes the action associated with the condition. An action may be to construct a mail message, set an abort flag, skip the next test-module ID, repeat the test-module, go to a specific test-module ID, or run a shell script. Examples of actions associated with conditions is further described relative to FIG. 4 . After the test-module results have been parsed, the next test-module ID is determined at block 380 . The selection is mainly determined by the action taken at block 370 . For example, if the just-processed test-module ID is 100 , and a skip action is to be executed as determined by parsing, the next test-module ID processed will be 102 (assuming an increment by one). Likewise, if a repeat action is to be executed, the next test-module ID processed remains 100 . If no branching action is determined by the parsing, then the next test-module ID would be executed. By the current example, the next test-module ID processed would be 101 . After the next test-module ID is determined at block 380 , the test-module sequence process continues by checking if any more test-modules are to be run at block 390 . If not, the test-module sequence ends at block 390 . If more test-modules are to be run, the process returns to block 360 for the further processing of test-modules in the test-module sequence.
[0056] FIG. 4 is an example of a flow diagram of processing an action according to another embodiment of the invention. As mentioned previously, the parsing at block 370 determines whether a branching action is to be executed based on test-module results of software-targeted testing-inquiries run on the subject system 160 and executes the branching action.
[0057] Assuming that branching is determined in block 370 , then flow proceeds to FIG. 4 starting at the input block 410 , where execution of an action begins. If the action is to send Mail as determined in block 420 , an SMTP packet may be constructed and sent, at block 425 , by the test management system 120 . If the action is to Abort as determined at block 430 , an abort flag may be set at block 435 . The abort flag may be used to abort the entire testing process.
[0058] If the action is to SKIP as determined at block 440 , the test-module ID may be incremented by two (again, assuming the example of a default increment of one) in order to skip the next test-module ID. If the action is to REPEAT as determined at block 450 , it may be determined by checking a flag and counter whether an improper loop is repeating at block 455 . If improper looping is occurring, the process continues to block 370 . If looping is not occurring, the repeat flag and counter may be set at block 460 .
[0059] If the action is to RUN, as determined at block 465 , the test-module ID may be set at block 470 to a test-module ID as determined by parsing. If the test-module ID cannot be found, a default of the next test-module ID in sequence may be selected. If the action is to EXECUTE SHELL, then a shell script or program may be run. This could be any program or command such as to reboot a system, mount new media, etc. After blocks 425 , 435 , 445 , 460 , 470 , and 480 , the parsing process of block 370 continues.
[0060] FIG. 5 is an example of a screen shot of a graphical user interface for creating a test-module sequence according to another embodiment of the invention. The screen shot includes an available test modules window 510 , a test module sequence window 520 , a test module source window 530 , a Test Engine window 540 , an Automation Software window 550 , a Mail Groups window 560 , and a Create Sequence button 570 .
[0061] In the available test modules window 510 , a list of available test-modules is displayed from which a user may select for testing the subject system 160 . For example, the list in the available test modules window 510 shows that the BAT Tests (batch tests) named Core 1 and Core 2 may be selected. The Core 2 test-module entry, in this example, includes a description field to describe the test-module and any associated script information. The listing for the Regression Tests and Current Work tests are similarly displayed. The Current Work entry may be used to show available test-modules not readily categorized. The test-modules that may be presented is determined by the engineers that design the templates that include the test-modules stored in the source control database 130 .
[0062] The test module sequence window 520 includes the test-modules selected by the user from the available test modules window 510 and user edits. Once the user has selected information from the available test modules window 510 as described in block 250 and places them into the test module sequence window 520 , the user may create and edit rules in the test module sequence window 520 . The example rules represented in the test module sequence window 520 for test-module Core 1 may be interpreted as: if a test-module is PASSED, send mail to the Passgroup; if a test-module returns a WARNING, send mail to the Testgroup; and if the test-module returns a FAIL, send mail to the Testgroup and abort. Similar conditions may be entered by the user in the test module sequence window 520 .
[0063] The entry of information into the test module sequence window 520 may be by a drag and drop method. For example, a user may simply drag a test-module entry from the available test modules window 510 into the test module sequence window 520 . Default states, potential distilled results, such as PASS, WARNING, and FAIL may appear under the selected test-module entry and default actions such as “Mail” may also be automatically provided once a test-module entry is entered into the test module sequence window 520 . Additionally, rules may be edited or entered by using drop down menus or by using text entry windows.
[0064] The test module source window 530 may designate the source of test-modules to be used in populating the available test modules window 510 . The test-module source entry may also be a location such as a directory name, URL, or other type of address.
[0065] The test engine window 540 may designate which test engine platform 150 to use. Entries may be in the form of a name or another type of address.
[0066] The automation software window 550 may designate which automation software to use. Entries may be in the form of a name.
[0067] The mail groups window 560 may designate the group of Email addresses to use from which a user may select mailing lists from.
[0068] The create sequence button 570 may be used to enter or save the test-module sequence.
[0069] The buttons 532 , 542 , 552 and 562 can be explore or browse buttons to facilitate making a selection in the windows 530 , 540 , 550 and 560 , respectively.
[0070] Although the example embodiments described above in connection with the invention are particularly useful in software and hardware testing systems, they may also be utilized other testing environments, as would be known to one of ordinary skill in the art.
[0071] It is noted that the functional blocks in the example embodiments of FIGS. 2-4 may be implemented in hardware and/or software. The hardware/software implementations may include a combination of processor(s) and article(s) of manufacture. The article(s) of manufacture may further include storage media and executable computer program(s). The executable computer program(s) may include the instructions to perform the described operations. The computer executable program(s) may also be provided as part of externally supplied propagated signal(s) either with or without carrier wave(s).
[0072] This specification describes various illustrative embodiments of the method and system of the invention. The scope of the claims are intended to cover various modifications and equivalent arrangements of the illustrative embodiments disclosed in this specification. Therefore, the following claims should be accorded the reasonably broadest interpretations to cover modifications, equivalent structures in features which are consistent with the spirit and the scope of the invention | A method and system for testing software that includes receiving a plurality of test-modules associated with an external system and organized into a sequence, each test-module including at least a software-targeted testing-inquiry that generates a plurality of intermediate results, the test module returning a distilled result based upon the results, receiving one or more rules to which at least one of the test-modules in the sequence is subject, application of each rule having one or more outcomes, at least one outcome for each rule being the determination of the next test-module to be administered, each rule including one or more actions conditioned upon the distilled result returned by the corresponding test module, the one or more conditioned actions being configurable to be a branch out of the sequence to a predetermined test-module; administering the sequence of test-modules sequentially except where a branch is invoked to administer the sequence from another point in the sequence, the administering of a current test-module including executing the current test-module, the executing including sending signal bits to the external system, and applying, if the current test-module is subject to one or more rules, such one or more rules. | 6 |
FIELD OF THE INVENTION
This invention relates to filters having self-cleaning gravity screens that utilize a dynamic backwash to keep the screen perforations open and to facilitate passage of retained material along the screen, and in particular to an improved drive system for the backwash.
BACKGROUND OF THE INVENTION
Gravity screens are widely used to separate solids from streams of water in order to produce an effluent useful for purposes such as irrigation or acceptability to a sewer, or as a first step in processing solid-laden streams ultimately to produce potable water.
A well-known example of gravity screen systems is shown in Wake U.S. Pat. No. 3,357,567. This patent is incorporated by reference herein its entirety for its showing of systems of this type, and of their utility.
For example, water in irrigation ditches generally is burdened with considerable organic trash and mineral particulates. It is undesirable to dump this material into a crop-growing area. Directing it first through a system according to this invention can clarify the stream to the extent that when applied to crops it is without this burden, and acceptable to crop land.
In addition to agricultural applications, this invention finds utility in many industrial applications where a water stream is used in processes involved in manufacturing or food preparation operations. Washings from vegetables and fruits, and even washings from floors, generate debris-laden streams that require removal of solids before the water can be used again, or before it can be discharged into a sewer.
This invention utilizes a rotating wand below the screen which, as it rotates around a horizontal axis, projects streams of water upwardly against the screen. Rotation of the rotary wand causes the emitted water streams to move along the screen so as to assist movement of the debris along the screen, as well as to prevent the screen perforations from becoming clogged.
The foregoing is known art, but it has suffered from a lack of reliable power for rotating the wand. One problem resides in the very slow rotation desired for the wands--on the order of 2 rpm. When sprinkler motors or electric motors are used, problems soon develop because their power and their output do not match the system requirements.
Because this device relates entirely to water systems, and a source of clean-enough water is available from the filter, a pump can be utilized to project a stream of water through a nozzle to a water wheel that can turn at a rapid rate which is greatly reduced by a gear reduction to drive the wand. This provides a powerful drive without a mechanical linkage to an electric motor. If for some reason the wands are stalled, no harm is done to the water wheel. In that unlikely event, it simply stalls and the pump continues to run without unfavorable consequences. The pump supplies water both for backwashing and for powering the wands, and ordinarily utilizes water which has already passed through the screen.
Accordingly it is an object of this invention to provide a compact system which downstream from a pump is entirely hydraulically actuated, and in which hose connections can be appreciably shortened and in many applications eliminated entirely.
BRIEF DESCRIPTION OF THE INVENTION
A filter system according to this invention utilizes a perforated screen having an upper and a lower surface with perforations which extend between them. A water-collection chamber is disposed beneath the screen. Supply means discharges a stream with material to be separated onto the upper surface. A rotary wand underneath the screen has an axis of rotation parallel to said lower surface. It has a plurality of laterally-directed nozzles which discharge water from the wand. When directed toward the screen, the nozzle streams impinge upwardly against the lower surface, and move along it. This tends to keep the perforations open, and also tends to move retained solids along the upper surface of the screen toward a debris collection chamber.
According to a feature of this invention, pump means draws previously filtered water from the water collection chamber, pressurizes it, and discharges it through a nozzle onto a water wheel. The force of the stream is exerted against blades on the wheel, and the wheel is turned. A gear reduction means is turned by the wheel, which in turn drives the wands. The wands are also connected to the pump discharge so that previously filtered water is discharged by the wands. Thus the water collection chamber contains only filtered water, some which has passed through the screen and some of which is recycled to it through the wands. Water from the water collection chamber is withdrawn for further use or discharge.
According to a preferred but optional feature of this invention, a plurality of wands are provided which are journaled to a supporting wall. They are driven by a belt system which in turn is powered by the gear reduction means.
According to yet another preferred but optional feature of the invention, the filter system can be provided in modules which can be assembled side by side, conveniently to increase the through put capacity.
The above and other features of this invention will be fully understood from the following detailed description and the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic end view of a module of the invention;
FIG. 2 is a cross-section, partly in schematic notation, taken at line 2--2 in FIG. 1;
FIG. 3 is a cross-section, partly in schematic notation, taken at line 3--3 in FIG. 2;
FIG. 4 is an oblique partial view, partly in schematic notation, showing the preferred embodiment of drive means; and
FIG. 5 is a fragmentary perspective view, partly in cutaway cross-section; showing two modules assembled to increase the flow-put capacity.
DETAILED DESCRIPTION OF THE INVENTION
A module 10 for a screen filter system is shown in FIG. 1. A pair of end walls 11, 12 and a pair of side walls 13, 14 and a bottom 15 form a water collection chamber 16.
A perforated screen 20 is laid atop the water collection chamber. It has a suitable slope, preferably about 5° to the horizontal. A drain port 21 drains water which has passed through the screen from the water collection chamber. This water is directed to any desired location, including to a pump 22 for powering the wands.
An inlet chamber 25 is formed along and spaced from side wall 13. It is formed as a well adjacent to side wall 13 and rises above its upper edge so that a water stream with a burden to be separated flows gently over the upper edge 26 of the side wall and onto the screen. This material flows downwardly over the screen. The water drains through the screen, and the burden is moved along toward side wall 14 by gravity, with the assistance of water streams to be disclosed below.
An apron 27 receives the burden and drops it into a suitable collection bin 28 or other collection means.
An advantage of the inlet chamber as described is that the inlet stream can enter the chamber through an inlet port 29 near the bottom of the module. There it can gradually rise to flow over the edge. This provides the advantages that the inlet piping can be located near to the ground, and that turbulence will be reduced as the stream rises in the inlet chamber. Ribs 30 (see FIG. 5) can be provided which extend horizontally along the inner walls of the inlet chamber. These appear to further reduce the turbulence in the incoming stream.
One or more wands 35, 36 are provided to assist the passage of the burden down the screen. In a practical system, at least two such wands will be provided, although only one, or three or more can be used, depending on the scale of the device.
The wands 35 and 36 are journaled to the end wall by bearings. Bearings 37 and 38 are water transmissive, to give access to the axial passages in the tubular wands. The wands are closed at their ends adjacent to bearings 39 and 40. The wands are identical. Each has a number of nozzle-like perforations 41 which project a stream of water laterally. When they are upwardly directed, they impinge on the bottom of the screen.
It is necessary that these rotate in the same direction so as to assist movement of the burden down the screen. They must be powered and provided with water to provide the jet streams.
A pump 50 draws water from the water collection chamber through pipe 51. The water is pressurized, and part of the output of the pump is returned through pipes 52 to the wands. Thus, filtered water is fed to the pump, and it in turn supplies water to feed the wands.
The pump also supplies, through pipes 53, water under pressure to power a water wheel 55. It is generally more convenient to place the water wheel outside of the structure, mounted to a side wall. The minor disadvantage is that spent water from it requires a conduit to convey it to the other filtered water.
Water wheel 55 includes a drive shaft 56 and a head 57 on the shaft. The head has a plurality of appropriately shaped vanes 58 spaced from the shaft, which successively pass through the path of a water jet 59 discharged from a nozzle 60. Jet 59 exerts a strong torque on the head, and the head will turn at a rapid rate, preferably on the order of about 200 rpm. This, of course, is too fast for the wands to rotate. For this reason a conventional gear reduction 61 is provided. A reduction of about 100:1 is useful to produce power at the output shaft 62, to rotate the wands at about 2 rpm. Other ratios and speeds can be selected, but the principle is the same--a considerable reduction in rotary speed from a water wheel rotated at a much higher speed, all to produce sufficient power reliably to rotate the wands.
The gear reduction may be placed inside or outside of the water collection chamber. Generally it will be placed inside. For transmission of power from output shafts 62 to the wands, a simple mechanical linkage is to be preferred.
In FIG. 4 output shaft 62 carries a pulley 63. Pulleys 64, 65 are fixed to the wands. Drive belts 66, 67 link pulleys 63, 64 and 63, 65. Observe that both wands will rotate in the same sense so as to drive the debris in the same direction.
It will be observed that the water lines in this installation can all be rigid pipe, and that their lengths can be kept to a minimum. The device provides good power, is reliable and rugged in the field.
Modules such as shown in FIG. 1 can be placed side by side so as to share an inlet chamber, instead of lengthening the device to increase capacity. In FIG. 5, two modules 60, 61 are placed side by side, and share a common inlet chamber 62. Water which upwells in chamber 62 flows out over both of the screens. Each module is provided with wand drive and wand supply means as previously described.
This invention is not to be limited by the embodiments shown in the drawings and described in the description, which are given by way of example and not of limitation, but only in accordance with the scope of the accompanying claims. | A self-cleaning gravity screen for removing particulate material from a liquid stream. The screen slopes, and beneath it a rotary wand sweeps against its lower side to keep the screen perforations open and assist movement of retained solids along the screen. The wand is driven by a rotary water wheel. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention.
[0002] The present invention relates generally to medical diagnostic methods and systems. More particularly, the present invention relates to methods and systems for detecting occult blood or other analytes in the water of the bowl of a flush toilet.
[0003] Colon and rectal cancers are a leading cause of death and disability throughout the world. Early detection and treatment of both diseases can significantly increase the chances of a patient's survival. A common diagnostic test for both diseases relies on the detection of occult blood in patient feces. Occult blood detection is most commonly performed by the patient obtaining small samples of fecal matter from stool following a bowel movement, spreading those samples thinly over a specially treated substrate, allowing the substrates to dry, and sending the dried substrates to a central laboratory or a doctor's office for testing. Usually, repeat samples will be taken over several days and collected prior to sending them for laboratory evaluation.
[0004] While quite useful if performed correctly, such home diagnostic stool testing suffers from both poor compliance and incompetent performance. Most patients are quite reluctant to process stool samples, even their own. Because of this reluctance, and undoubtedly for other reasons as well, many patients are unable to properly collect the samples, apply them to the substrates, and maintain the samples in proper condition before they are sent to the testing laboratory. Because of these problems, many patients who had been advised to sample their stools never complete the home testing program, and many of those tests which are completed are compromised so that the test reliability is reduced.
[0005] To promote compliance and reduce complexity, performance of occult blood assays directly in the water bowl of a toilet has been proposed. A variety of tablets, solid phase substrates, and other diagnostic agents have been formulated, where the user can simply drop these agents into the toilet bowl after use. While theoretically increasing patient compliance, the patient can still make mistakes in adding the reagents. The addition of dried reagents and related carriers can present mixing problems which limit the accuracy of the test. Moreover, the completion of such testing requires patient compliance, which is frequently absent due to a variety of factors.
[0006] For these reasons, it would be desirable to provide improved methods, systems, and reagents for performing occult blood testing in situ in the water bowl of a flush toilet. It would be further desirable to provide such methods and systems which are also useful for detecting other analytes in an analogous manner. The methods and systems should further reduce or eliminate the level of skill required by the patient to perform the assay. It would be particularly desirable if such methods and systems were to proceed automatically each time a toilet is used for defecation or urination, either by responding to the flushing of the toilet or to the use of the toilet in other ways. Such methods and systems would desirably further provide for unambiguous results and permit easy reading of those results by the patient. At least some of these objectives will be met by the inventions described hereinbelow.
[0007] 2. Description of the Background Art.
[0008] The preparation of dried reagents which may be added to stool in a toilet to perform occult blood assays is described in U.S. Pat. No. 4,956,300. Other patents of interest include U.S. Pat. Nos. 6,271,046 B1; 6,221,678 B1; 6,186,946 B1; 5,196,167; 5,192,501; 5,081,040; 4,725,553; 4,625,160; 4,672,654; 4,541,987; 4,511,533; 4,175,923; and 2,828,377. Toilets which are capable of performing many functions, including measuring blood in urine, are predicted in “Japanese Masters Get Closer to the Toilet Nirvana,” New York Times, Oct. 8, 2002.
BRIEF SUMMARY OF THE INVENTION
[0009] According to the present invention, occult blood and other analytes symptomatic of gastrointestinal disease are detected by the addition of a dye reagent directly into the water of the bowl of a flush toilet. The dye reagent reacts with the analyte, if present, to produce an observable signal, usually a color change in the water.
[0010] In a first aspect of the present invention, the dye reagent is dispersed into the water, typically being in a liquid, gel, powder, or solid form which rapidly dissolves in the water and mixes stool sample to promote accurate and immediate results. In a second aspect of the present invention, the dye reagent is dispensed into the toilet bowl water in response to use of the toilet, such as flushing, sitting, or by the selective manual activation of a dosing unit. In the third aspect of the present invention, systems are provided for automatically dispensing the dye reagents into the toilet bowl water in response to use.
[0011] Dispersing or otherwise adding an amount of a dye reagent in the toilet bowl water according to the first aspect of the present invention requires that the reagent be in a dispersible and/or soluble form, usually being solution (liquid), gel, powder, or solid form which rapidly dissolves and/or dispenses in the toilet bowl water. Such dispersible forms generally exclude tablets, solid phase substrates, and other forms which will not rapidly mix or dissolve with the toilet bowl water and with the stool sample therein. Usually, although not necessarily, such dispersible dye reagents will be dispensed automatically in response to a use of the toilet, as will be described in more detail hereinbelow. Less preferably, however, the dispersible forms of the dye reagent may also be selectively or manually released into the toilet bowl water, where they will quickly mix and react with the stool, producing an observable signal when the analyte is present.
[0012] The automatic dispensing of a dye reagent, according to the second aspect of the present invention, will include the release of both dispersible and non-dispersible forms of the dye reagent. That is, in addition to the liquid, gel, and powder forms of the dried reagent, the present invention further comprises automatically dispensing even non-dispersible forms, such as tablets, substrates, solid phases, and the like. Such automatic release may be in response to any use of the toilet, including flushing, sitting on the seat of the toilet, electronic proximity sensing of a patient using the toilet, detection of fecal matter entering the toilet bowl water, detecting a change in water level or turbulence in the water of the toilet bowl alter any use, including vomiting, and the like. The latter relative use detection is particularly advantageous since it avoids the dispensing of reagent when the toilet is used without fecal matter entering the toilet bowl.
[0013] In all aspects of the methods of the present invention, the dye reagent may be dispensed into the water in the toilet tank, directly into the water in the toilet bowl, or as some combination of both. For example, when the dye reagent comprises both a dye and a separate oxidizer, as described in more detail below, the dye and the oxidizer may be dispersed together or separately into the water, with either or both going into the water in the toilet tank or into the water in the toilet bowl.
[0014] The methods of the present invention preferably provide for dispensing or releasing measured amounts of the dye reagent into the tank, typically in response to flushing. Usually, such dispensing comprises dropping a measured amount of a liquid, gel, or powder. In other instances, however, dispensing may comprise dissolving an amount of a solid dye reagent (or reagent component) into the tank or the bowl of the toilet.
[0015] In all instances, the presence of the dye reagent in the toilet bowl water will produce an observable signal in the presence of blood or other analyte, typically producing a color change in the presence of blood in the water of the toilet bowl. Preferably, the dye reagent will be selected and provided in an amount which produces an observable color change at a local blood concentration in the water of 0.2 ppm and above, preferably 0.1 ppm and above. Exemplary reagents comprise an oxidizer and a dye, where the oxidizer oxidizes the dye to produce a color change in the presence of a catalyst-peroxidase from blood hemoglobin. Exemplary dyes include 3,3′ 5,5′-tetramethylbenzidine, gum guaiac, potassium guaicosulfonate; phenolphthalin, 3,3′-dimethylbenzidine, o-toluidine, 4,4′-diaminobiphenyl, and the like. Exemplary oxidizers include alkali metal perborates, OXONE, hydrogen peroxide, and the like. Immunochromatographic detection employing a monoelonaldehyde conjugal with polyclonal antibodies might also be possible.
[0016] Optionally, the methods of the present invention may further comprise selectively adding a control reagent to the toilet bowl water to confirm that the system is working and optionally calibrate the system. Suitable control substances include ______.
[0017] Systems according to the third aspect of the present invention provide for automatically dispensing a dye reagent into water in a bowl of a flush toilet. The systems include a reservoir holding a dye reagent which is capable of producing an observable signal in the presence of analyte in the toilet bowl water, and a mechanism for dispensing an amount, preferably a measured amount, of the dye reagent into the water in the toilet bowl in response to a use of the toilet. The dispensing mechanism may be configured to release the dye reagent in the water in the toilet bowl, or the water in the water tank, or some combination thereof, so that the water and dye reagent are mixed in the toilet bowl. The dispensing mechanism may comprise a mechanical device which detects flushing of the toilet and/or rise of water in the toilet bowl or toilet tank and which releases a pre-measured amount of the dye reagent in response to such detection. The pre-measured amount may be in the form of a liquid, gel, powder, or optionally be in a solid form, such as a tablet, solid phase substrate, or the like. Alternatively, the dispensing mechanism may dispense dye and oxidizer separately into the water, where the dye and/or oxidizer may be in any of the forms just mentioned. The dye reagent will be selected to provide an observable signal, the presence of the analyte typically producing a color change in the water in the presence of the analyte, such as blood. In the case of blood detection, the preferred detection ranges, reagent dye systems and the like, have been set forth above. The systems of the present invention may further comprise a control substance which may be added to the toilet bowl water to produce the observable signal when added to the water in the absence of the analyte.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] [0018]FIG. 1 is a schematic illustration of a system according to the present invention comprising a dye dispensing or dispersing apparatus in the toilet tank of a toilet.
[0019] [0019]FIG. 2 is a schematic illustration of an alternative system according to the present invention wherein the dispensing or dispersing apparatus is located in the toilet bowl of the toilet.
[0020] [0020]FIG. 3 is a schematic illustration of a third embodiment of the system of the present invention comprising an electronic toilet use detector which can be arranged to control dispensing or dispersing of the dye reagents into either the toilet bowl or the toilet tank, or both.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Methods and systems according to the present invention will most commonly be used to detect fecal occult blood in stool samples in the bowl of a toilet. Such tests are useful for the early detection of colon cancer, rectal cancer, and other cancers of the gastrointestinal tract. While the tests of the present invention will not be finally determinative of disease status, they will be very useful in alerting patients of the need to contact their physicians and have further testing done. In addition to the detection of fecal occult blood, the methods and systems of the present invention will also be useful to detect other analytes associated with diseases causing appearance of certain substances in gastrointestinal tract like increased level of bilirubin in certain blood disorders, porphyrins in porhyrias, specific microorganisms in gastrointestinal infections, increased fecal fat levels in pancreatic exocrine insufficiency and others. Changes in the urine chemistry may detect diabetes (increased sugar level), renal insufficiency (proteins), renal malignancies or stones (urinary blood), increased urine calcium in parathyroidism, cathecholamines in pheochromocytoma, urine free cortisol in Cushing's disease and others.
[0022] A particular advantage of the present invention is that it provides for automatic and daily screening of a patient's condition. As mentioned before, the screening will not be determinative of disease status, but will allow the patient to seek further diagnosis. For example, in the case of suspected colon or rectal cancer, subsequent screening by colonoscopy or sigmoidoscopy would likely be in order.
[0023] The dye reagents useful in the present invention may take a variety of forms. Most simply, the reagent can be in the form of a dissolvable block which is placed in the toilet bowl or toilet tank so that it is exposed to water each time the water in the bowl or tank is replenished. Upon exposure to water, a pre-determined portion of the block will dissolve and release the dye reagent into the water. Such systems are commonly available for releasing cleaning and disinfecting reagents into toilets.
[0024] Alternatively, the dye reagent may be released into the toilet bowl and/or toilet tank using a mechanical system which dispenses a pre-measured amount of the reagent in response to a use of the toilet, such as flushing, sitting, or the like. In the case of flushing, the mechanical linkage can be made directly to the handle or valve mechanism which initiates the flush, or it can be indirectly made to a response in the change of water level in the toilet bowl or tank. Such mechanical systems may release pre-measured amounts of the liquid, gel, powder, or other dispersible forms of the dry reagent. Alternatively, the mechanical systems can release single or known numbers of tablet(s) upon each use of the toilet.
[0025] The present invention can further utilize electromechanical systems where various system components can be powered or motorized to enhance response. Additionally, the electromechanical systems can have electronic sensors incorporated for detecting a variety of events suitable for controlling the release of the dye reagents. For example, sensors can sense the physical presence of a user, the positioning of the user on the toilet seat, release of fecal matter and/or urine into the toilet bowl water, or the like. Sensing these various events can be used to control the release of the dye reagent using mechanical or electromechanical release means.
[0026] Generally, in the present invention, a reagent will be added to a toilet water. A component of the reagent will react or bind with an analyte giving a characteristic and specific system change when the analyte is present. The change may be a color change or change of electric potential of toilet bowl solution specific for the analyte. Preferred dye reagent according to the present invention will comprise a dye and an oxidizer, wherein the oxidizer oxidizes the dye to produce a color released in the water in the presence of the analyte which acts as a catalyst. Exemplary dyes include 3,3′,5,5′-tetramethylbenzidine, gum guaiac, 3,3′-dimethylbenzidine, o-toluidine, 4,4′-diaminobiphen, and the like. A particularly preferred system is the combination of 3,3′,5,5′-tetramethylbenzidine and OXONE which reacts to produce blue dye in the presence of hemoglobin.
[0027] Referring now to FIG. 1, first exemplary system 10 constructed in accordance with the principles of the present invention comprises a dispenser 12 which is mountable within the tank TA of a toilet T. Dispenser 12 is positioned so that it is at least partially covered by water when the tank TA is replenished after flushing. The immersion of the dispenser 12 in water will automatically cause the release of an amount of dye reagent into the water, as indicated by the arrow. The release can be by simple dissolution, by mechanical release (e.g. opening and closing of a float valve or similar mechanical mechanism), by electronic sensing of the water level and a motorized or other powered release of dye from the dispenser 12 , and the like. The released dye reagent will remain in the water in the toilet tank until the toilet is next flushed, when the water will enter the toilet bowl B, where it will remain until the use of the toilet by a patient.
[0028] An alternative system 20 as shown in FIG. 2, relies on a dispenser 22 present in the bowl B of the toilet T. The dispenser 22 may take generally the same forms as described above with respect to sensor 12 in FIG. 1, except that the release will be in response to changes in water level within the toilet bowl B.
[0029] Additional systems 30 according to the present invention are illustrated in FIG. 3. Such systems 30 will comprise an electronic controller 32 which controls operation of a first dispenser 34 located in the toilet bowl B and/or a second dispenser 36 located in the toilet tank TA. New electronic control 32 may comprise one or more sensors which detect a toilet use, such as a water level change, sitting on the seat of the toilet, proximity of the patient to the toilet, the presence of fecal matter and/or urine in the water of the toilet bowl, or the like. In response to one or more of these sensed conditions, the control may cause the first dispenser 34 and/or the second dispenser 36 to release one or more components of the dye reagent into the water in the bowl and/or tank, respectively.
[0030] The invention has been described above in conjunction with particular embodiments. One skilled in the art, however, will appreciate that there are many alternatives, modifications, and variations of the embodiments which will fall within the scope of the claims below. The present invention is intended to embrace all such alternatives, modifications, and variations within these claims. | Methods and systems for detecting occult blood and other analytes in the water of a toilet bowl release a dye reagent into the water which produces an observable signal in the presence of the blood. The dye reagent is preferably dispersed as a liquid, powder, gel, or other form which rapidly mixes and combines with the sample. Usually, automatic mechanical or electromechanical dispensing systems are used to release the dye reagent into the water. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority from Brazilian Patent Application No. PI0902530-8, filed Jul. 29, 2009, the content of which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention pertains to the field of mechanical engineering, more specifically, electromechanical devices, commonly known as household appliances, especially washing machines, more specifically a suspension system for washing machines
BACKGROUND
In top loading washing machines, the drive unit is commonly defined by an electric motor coupled to the drive shaft, directly or by means of transmission and fixed upon a support frame that is affixed or incorporated, in one piece, to the external lower side of a lower wall of the tub, wherein the assembly defined by the drive unit, vertical drive shaft and rotary basket remains fixed to the tub, conveying to the latter all the vibrations and oscillations caused by the spin of the basket during the washing and centrifugation operations, particularly when a centrifuge with eccentric masses results from a non-homogeneous distribution of the load of clothes inside the basket. In this common construction, the tub vibrates and oscillates in conjunction with the basket and the drive unit.
In the type of construction described above, the tub defines a structure that cannot be directly supported on the floor, due to the movement to which it is subjected during the machine operation. Thus, the provision of means of suspension that are able to absorb or dissipate at least a portion of the vibrating energy transmitted to the tub is required.
The solution known to circumvent this issue necessarily involves the provision of a cabinet encompassing the tub and the drive motor, the cabinet being supported directly on the floor. This arrangement includes the provision of constructive means of suspension, usually in the form of springs or other elastic elements, mounted on fixed rods, on the one extreme, in the region of the lower wall of the tank and at the other extreme, the upper inner portion of the cabinet.
Despite being widely used, this constructive solution of the prior art requires the provision of a cabinet to operate as a support structure for the remainder of the machine and also as a fixed housing, involving oscillating parts of the machine and operating as a defining element of the aesthetic aspect the machine. Besides being one more element in the construction of such machines, the cabinet leads to an increase in the dimensions of the whole assembly, as it has to internally accommodate the means of suspension, providing a circumferential backlash against the tub, still enough to prevent the latter to conflict with the cabinet during centrifuge operations with an eccentric load of laundry.
In another known solution, the drive motor is fixed to the vertical drive shaft passing through the bottom of the tub and carrying the rotary basket, the drive motor being attached to a support frame which is in turn backed by a base structure seated on the floor, by means of suspension including springs and shock absorbers. In this construction, the tub is mounted on a frame support, passing to oscillate and vibrate together with the basket and the drive motor when the machine is in operation. Although the means of suspension are fitted below the support frame, allowing the structural function of the cabinet to be limited in terms of support frame, the provision of a cabinet with sufficient height to encompass the whole of the tank is required in order to protect it visually and operationally during machine operation, as the tank oscillates and vibrates together with the basket and the drive motor.
Brazilian Patent Application No. PI0601707 (corresponding to U.S. Publication Application No. 2007/0251278) provides a top loading clothing washing machine that includes: a basic structure of a generally tubular form, to be inferiorly supported on a floor, a tank for containing a washing liquid and fixed on the basic structure, a support frame suspended within the basic structure; means of suspension absorbers of vibratory and oscillatory movements and connecting the frame to support the basic structure in order to keep the first suspended inside the last one; a drive motor disposed within the basic structure, fixed to the support frame and carrying a drive shaft extending vertically upward, into the tank and a rotating basket provided inside the tank and operatively and selectively associated with the drive shaft.
BRIEF SUMMARY OF SELECTED INVENTIVE ASPECTS
To circumvent the problems described in the above techniques, provided in an aspect of the invention is a suspension of a washing machine with the mechanical assembly supported on the bottom of the cabinet through a lower suspension including plates and shock absorbers (e.g., spring and dampener assemblies) and a casing containing liquid (e.g., water). Such a configuration is advantageously applied to washing machines with cabinets having a reduced load support capacity in their upper region, originated from the washing set, for example: plastic cabinets, or in cabinets that also serve as a static water tub with an inner rotary basket. The suspension demonstrates an innovation in its design, e.g., in that the washing set (wash group) is supported on the bottom of the cabinet with a bottom suspension including shock absorbers (e.g., spring and dampener assemblies) and a casing containing liquid (e.g., water). The shock absorbers connect a top mobile plate to a bottom fixed part (e.g., plate) of such suspension and the liquid containing casing is mounted on the top mobile plate offset from the drive motor.
In one aspect, the invention comprises a suspension of washing machines with a mechanical assembly resting on the bottom of the cabinet by means of a lower suspension including plates and shock absorbers (e.g., spring dampener assemblies) and a liquid containing casing, as aforesaid. The suspension system is intended to absorb the movement of the mechanical assembly in the centrifuge, reducing the transmissibility of forces/movement to the external cabinet.
The use and correct sizing of the liquid containing casing as a counterbalance to the motor is a cost-effective solution that ensures proper kinematics during the spin cycle for this type of washing machine with a lower support of the washing assembly (wash group). This leads to greater orbits at the top of the basket than at the bottom, thus reducing the lateral movement of the mobile plate of the suspension and the transmission of side forces/movement to the cabinet, therefore minimizing the moving effect of the machine during spin cycles.
This summary is provided to introduce a selection of concepts of the inventive subject matter that are further described below in the detailed description. This summary is not intended to identify essential features or advantages of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Additional features and advantages are further described below.
BRIEF DESCRIPTION OF THE DRAWINGS
Aspects of the invention are illustrated by way of example and not by limitation in the accompanying figures in which like reference numerals indicate similar elements and in which:
FIG. 1 is a schematic view of the suspension system ( 1 ), which suggests the movement of the basket ( 2 ) inside the cabinet ( 3 ).
FIG. 2 is an exploded view in perspective of the suspension assembly ( 1 ), showing its integrated parts: liquid containing casing ( 4 ), upper mobile plate ( 5 ), springs and shock absorbers ( 6 ) and lower fixed plate ( 7 ).
FIG. 3 is an exploded view in perspective of the suspension assembly, including a mounting cushion (with plates 5 and 7 ) and liquid containing casing ( 4 ) separated from the whole.
FIG. 4 is an exploded view in perspective of the suspension assembly, including a mounting cushion (with plates 5 and 7 ) and liquid containing casing ( 4 ) separated from the whole.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
An embodiment of the invention comprises a suspension ( 1 ) of a washing machine with a wash group assembly resting on the bottom of the washing machine cabinet ( 3 ) by means of the suspension. The suspension provides a lower cushion including plates ( 5 and 7 ), shock absorbers ( 6 ) and liquid containing casing ( 4 ). The shock absorbers ( 6 ) may comprise spring and dampener assemblies, as best seen in FIG. 2 . This may comprise a coil spring and coaxially arranged rod and piston type dampener, seated within a circular socket of the lower plate, the piston of the dampener being slideable with friction in a corresponding cylinder formed in the upper plate 5 .
The cushion or suspension ( 1 ) that connects the wash group assembly to the bottom portion of the cabinet ( 3 ) is comprised of two parallel plates ( 5 and 7 ) connected via the shock absorbers ( 6 ).
An upper mobile plate ( 5 ) of the cushion is fixed to a transom ( 11 ) of the mechanism assembly and another lower one ( 7 ) is fixed to the bottom of the cabinet ( 3 ). Both plates ( 5 and 7 ) are connected via a set of shock absorbers ( 6 ) as aforesaid in order to absorb the vibration energy of the washing set (wash group) ( 2 ) during the spin cycle, minimizing the transfer of energy to the cabinet ( 3 ).
The suspension system ( 1 ) includes a liquid containing casing ( 4 ) fixed on the upper moving plate ( 5 ) of the cushion in order to increase its mass impedance, reducing the accelerations in such portion and serving as a counterweight for the system (e.g., offset motor 8 ). In an exemplary embodiment, the liquid within the liquid containing casing ( 4 ) is, or comprises, water.
For a better understanding, the mode of operation of the suspension ( 1 ) can be noted in FIG. 1 . The bottom cushion or suspension, comprised of the plates ( 5 and 7 ), shock absorbers ( 6 ) and liquid containing casing ( 4 ) connects the washing assembly ( 2 ) to the bottom of the cabinet ( 3 ). The two parallel plates ( 5 and 7 ) are connected by the shock absorbers ( 6 ); the liquid containing casing ( 4 ) is fixed on the upper moving plate ( 5 ) of the cushion, in order to increase its mass impedance. As seen in FIGS. 2-4 , the liquid containing casing ( 4 ) is generally of a U-shaped configuration and is fixed on the upper moving plate ( 5 ) by way of a plurality of posts protruding from the top surface of the upper moving plate ( 5 ).
In FIGS. 2 , 3 and 4 it can be noted in detail, in a sequence of engagement, the constructive arrangement of the suspension assembly ( 1 ) composed of the upper mobile plate ( 5 ) of the cushion, fixed to the transom ( 11 ) of the mechanism assembly and another lower one ( 7 ) fixed to the bottom of the cabinet ( 3 ) and the two plates ( 5 and 7 ) being connected by a set of shock absorbers ( 6 ) as aforesaid. On top of this sub-assembly is mounted the liquid containing casing ( 4 ). As diagrammatically depicted in FIG. 1 , the suspended wash group assembly comprises spinning basket ( 2 ), a central drive shaft ( 9 ) attached to and extending into basket ( 2 ). As depicted in FIG. 1 , on the lower end of drive shaft ( 9 ) is a pulley ( 10 ) that is operatively connected with a shaft (not shown) of drive motor ( 8 ) through a belt or the like (not shown). The transom ( 11 ) of the wash group assembly provides a mounting location for the upper moving plate ( 5 ) and attached liquid containing casing ( 4 ). Offset from that is a mounting location where drive motor ( 8 ) is located.
This invention is not limited to the representations mentioned or illustrated herein, and it has to be comprehended in its wide scope. Many changes and other representations of the innovation will come in mind of those skilled in the art to which this innovation belongs, having the learning benefit presented in previous descriptions and attached drawings. Further, it is to be understood that the innovation is not limited to the specific form disclosed, and that changes and other forms are understood as being included within the scope of the attached claims. Although specific terms are used herein, they are only used in a generic and descriptive form and not for a limiting purpose. | A suspension ( 1 ) of a washing machine has a mechanical assembly resting on the bottom of the cabinet ( 3 ) by means of a lower cushion including plates ( 5 and 7 ) and shock absorbers ( 6 ) and a liquid containing casing ( 4 ). The suspension system ( 1 ) is intended to absorb the movement of the mechanical (wash group) assembly during a centrifugal spin, reducing the transmissibility of forces/movements to the external cabinet ( 3 ), while the liquid containing casing provides a cost-effective counterbalance within the system. | 3 |
This is a Division of application Ser. No. 08/045,192, filed on Apr. 13, 1993, now U.S. Pat. No. 5,273,697.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to foamed elastomeric polymers with a particular color scheme, specifically a visual camouflage appearance. More particularly the invention relates to a camouflage pattern characterized by distinct, randomly sized regions of various colors, each such region having nonangular borders and being a single, uniform color with substantially no blending of colors within it, with all color changes occurring at interfaces of distinct colored regions. The material is also free from marring by large gas pockets in and on the surface thereof. The invention further relates to a process for manufacturing the foamed elastomeric polymer.
2. Description of the Prior Art
Foamed materials have long been utilized in the polymers industries. Foamed polymers generally exhibit greater strength than an identical mass of the unfoamed polymer, and in many cases drastically reduces the thermal conductivity of the material because of the air contained in the cells of the foam.
Camouflage designs for foamed materials are likewise known. Such designs most frequently are applied by painting the outer surface of the foam. Attempts to achieve an internal camouflage appearance have resulted either in an unacceptable visual camouflage effect characterized by smeared, blended colors, or simply alternating bands of color with no random distribution of distinct areas of color, and thus no camouflage effect at all.
U.S. Pat. No. 4,417,932 to Brietscheidel et al. discloses a process for producing sheets of stratified material from synthetic resin foam particles. Foam particles are scattered onto a conveying means, and superficially preheated during conveyance to a temperature between 100° C. and 160° C. The particles are then fed into a free-fall zone, in which they are further heated to a temperature of at least 200° C. After piling the particles onto a support surface, a sheetlike layer is formed by compacting the particles, and the sheet is then sized with simultaneous cooling.
U.S. Pat. No. 4,142,015 to Bienz discloses a thermal and visible camouflage for use on military equipment such as tanks. A layer of foamed plastic with a randomly varying insulating effect is applied to the outer surface of heat-generating equipment. Visual camouflage may be painted onto the plastic, or coatings under the plastic layer may also be used.
U.S. Pat. No. 4,243,709 to Morton discloses a method for making camouflage from sheets of multi-colored coated fabric. A film of camouflage polyvinyl chloride film is applied to each side of the fabric. The films are formed by applying plastisols of different colors to a carrier web, then overcoating the colored portions and any uncoated portions with a plastisol of another color. The films are then bonded to the fabric and the web is stripped from the outsides of the fabric. The multi-colored fabrics are cut into sheets which are attached to a net to make the camouflage screen.
U.S. Pat. No. 3,119,729 to Ljungbo discloses a flameproof camouflage net and method of manufacturing it. An apertured, flameproof sheet of plastic, or pieces thereof, are bonded by an adhesive to a net.
U.S. Pat. No. 2,054,848 to Bowker discloses a method of coloring thermoplastic materials to simulate the appearance of natural rocks and minerals, such as onyx. The thermoplastic is kneaded at elevated temperature with a solvent. The solvent is driven off and the material is formed into slabs by heated rolls. Coloring agents are applied to each slab, along with plasticizers as desired. An uncolored slab is superimposed over the colored slab, and the two slabs are worked by heated rolls until the desired effect is obtained.
A need thus exists for a camouflage material which has a nonrepetitive camouflage appearance on its surface and throughout its internal mass wherein virtually no blending of colors occurs at the interfaces of distinct colored regions.
SUMMARY OF THE INVENTION
Applicant has unexpectedly discovered a cross-linked, foamed elastomeric polymer with a nonrepetitive, visual camouflage appearance on its surface and throughout its internal mass.
Applicant has also discovered a novel process by which a camouflage material can be obtained wherein uncured cross-linkable elastomeric polymer pieces are first compounded in a mixing means with a foaming agent, commonly referred to in the art as a "blowing agent," a cross-linking agent, and coloring compounds. The resulting colored batches of polymer, having the blowing agent and cross-linking agent internally dispersed, are then cut into small pieces or strips of a desired size with a cutting means. Finally, the colored pieces are cured by foaming and cross-linking. This is accomplished by compressing the materials in a curing means to a pressure of up to about 2000 psi (144 kg f /cm 2 ) while heating to a temperature of between about 100° C. and about 500° C. During the curing step, the cross-linking and blowing agents which have previously been compounded into the polymer pieces are activated. The cross-linking of polymer molecules creates a rigid, unified material from the separate polymer pieces. The blowing agent, upon decomposition, creates gas bubbles which effect a foamed, cellular structure within the material. The materials are then depressurized, and the cured, foamed material is recovered from the curing means and cooled.
A third embodiment of the present invention is a novel material having a visual camouflage appearance obtained by the process comprising compounding uncured batches of the polymer in a mixing means with a blowing agent, a cross-linking agent, and coloring agents to obtain colored, uncured polymer pieces with internally dispersed blowing and cross-linking agents. The colored, uncured cross-linkable elastomeric polymer pieces are fed into a curing means and cured by foaming and cross-linking the colored polymer pieces. This is achieved by compressing the materials in the curing means to a pressure of up to about 2000 psi (144 kg f /cm 2 ) while heating to a temperature of between about 100° C. and about 500° C. The materials are then cooled and depressurized, and the cured, foamed material is recovered from the curing means.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing summary, as well as the following detailed description of a preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings in which:
FIG. 1 is a graph of pressure and percentage of cross-linking versus time, illustrating the interaction between the rate of cure and the rate of decomposition of three blowing agents which decompose at different rates.
FIG. 2 is a graph of pressure and percentage of cross-linking versus time illustrating the interaction between the rate of decomposition of a single blowing agent and three different, successively faster cure rates.
DETAILED DESCRIPTION OF THE INVENTION
The camouflage material of the invention constitutes foamed polymers made from cross-linked elastomeric polymers. More particularly, they are a foamed polymeric material, made from cross-linked elastomeric polymer, having a nonrepetitive camouflage appearance on its surface and throughout its internal mass. It is distinguished from the prior art in that it has a nonrepetitive, visual camouflage appearance throughout its entire structure.
The novel material of the invention has a high-quality visual appearance and its shock-absorbing and thermal capacity as a foam renders it uniquely advantageous for many commercial applications. It may be used as insulation in, for example, clothing and beverage can holders, as body protective gear such as helmets, in a wide variety of sporting goods such as foamed diving suits, hunting equipment, and in protective sport padding equipment such as for baseball and football, in footwear, and in military equipment, besides many other uses where a camouflage appearance is desired.
The camouflage material is preferably produced by a curing procedure which involves controlling the rheological properties of the polymer and the relationship between the cure rate and the blowing agent decomposition rate. Control of relationship between the cure rate and the blowing agent decomposition rate enables one skilled in the art to avoid both blistering and an unacceptable blending of colors in the material. The process consists of the following steps: compounding uncured polymer batches by mixing the blowing, cross-linking, and coloring agents with the polymer in a mixing means, cutting the batches of colored polymer into small pieces, feeding the colored, compounded pieces into a curing means, curing them with heat and pressure for a desired time period, depressurizing the cured material, and removing the cured material from the curing means and cooling it.
The process begins by mixing the uncured polymer to be foamed with the blowing agent, the curing agent, and coloring agents to form batches of various colors of foamable, cross-linkable elastomeric polymer. The uncured cross-linkable elastomeric polymer can be selected according to the properties desired for the final product. Any foamable elastomeric polymer may be used. Uncured polymers commonly used include but are not limited to polyurethane, polyethylene, polypropylene, neoprene, isoprene, ethyl vinyl acetate copolymer (EVA), butadiene-acrylonitrile copolymer (NPR), and styrene-butadiene copolymer (SBR) and mixtures thereof. Halogenated derivatives of the foregoing polymers are also acceptable, as well as mixtures thereof. While specific polymer species have been recited, it should be recognized that other polymers may also be acceptable without departing from the spirit and scope of the invention.
The foamable polymer pieces may be compounded in batches of various colors in a conventional mixing apparatus, such as Banbury mixer, and calendared to form sheets of different colors. To obtain pieces of differing sizes and shapes, a rotary cutter with a variable knife speed and a feeder with a strip cutter and variable speed and feeding angle are used. Other methods of preparing the polymeric pieces may be used without departing from the scope of the invention. Extrusion, for example, may be used to obtain fixed cylindrical or amorphous pieces to resemble pebbles, streaks, and other structures.
In the art of foamed polymers the use of blowing or foaming agents is well known. Any blowing agent acceptable in this art may be used in the novel process described herein. Azo compounds, N'-nitroso compounds and sulfonyl hydrazide compounds are three particularly preferred types of blowing agents. Furthermore, mixtures of these groups of compounds may also be used herein. Among azo compounds, azodicarbonamide, azobisisobutyronitrile, and diazoaminobenzene are preferred blowing agents. Among the nitroso compounds, N,N'-dimethyl, N,N'-dinitrosoterephthalamide, and N,N'-dinitrosopentamethylenetetramine are preferred blowing agents. Exemplary sulfonyl hydrazide blowing agents include: benzenesulfonyl hydrazide, toluene-(4)-sulfonyl hydrazide, benzene-1,3-disulfonylhydrazide, diphenylsulfon-3,3'-disulfonyl hydrazide, and 4,4'oxybis(benezenesulfonyl hydrazide). Mixtures of the blowing agents may also be used.
A wide variety of cross-linking agents may also be used including without limitation organic peroxides such as dicumyl peroxide. Other known cross-linking agents may also be used, such as rubber vulcanizing agents.
In addition to the coloring, blowing, and cross-linking agents, additional materials may also be compounded into the uncured polymer batches in order to modify the rheological properties and the activation of the blowing agent and curing agent of the foamed polymer. These additional materials may include viscosity-modifying agents, dispersion agents, blowing agent activators, cross-linking agent activators, and fillers. These agents are useful to enable one skilled in the art to design a compound which will produce a foam with a desired texture and appearance in accordance with the process here disclosed.
Exemplary viscosity-modifying agents include natural rubber and other polymers with high viscosity. They are added in amounts up to about 30% by weight, preferably up to about 25% by weight, and more preferably to about 20% by weight.
Exemplary dispersion agents include stearic acid and other surfactants, added in amounts of up to about 10% by weight, preferably up to about 5% by weight, and more preferably from about 1% to about 3% by weight.
Exemplary blowing agent activators include zinc oxide, dibasic lead phthalate, ethylene glycol, and urea and derivatives thereof. They may be added at up to about 15% by weight, preferably up to about 10% by weight, and more preferably up to about 5% by weight.
Exemplary filler materials may be either active or inert. Active fillers include metal silicates such as aluminum silicate, added in amounts up to about 50% by weight, preferably up to about 25% by weight, and more preferably up to about 20% by weight. Inert fillers include metal carbonates, such as calcium carbonate, added in amounts up to about 60% by weight, preferably up to 55% by weight, and more preferably up to 50% by weight.
Exemplary tackifiers include hydrocarbon resins such as Strukol 60 NSF, added in amounts up to 15% by weight, preferably up to about 10% by weight, and more preferably up to about 5% by weight. Tackifiers also alter the rheological properties of the compound. Other tackifiers may be selected from the group consisting of synthetic or natural resins, olefins, oils, soaps, and derivatives and combinations thereof.
After the uncured polymer pieces are compounded, they are cut into small pieces by conventional means known in the art, such as a rotary cutter, and then cured. Differently colored compounded polymer pieces are fed into the curing means and cured by a cross-linking reaction among the polymer molecules; simultaneously, the blowing agent decomposes exothermically into a gas, increasing the pressure within the mold and also accelerating the rate of cross-linking. The process can be used to obtain either open-celled or closed-cell foams by partially or completely filling the mold, and by heating the material at atmospheric pressure or at higher pressures, respectively. To obtain a closed-cell foam, the polymer pieces are compressed in the curing means to a pressure of between 0 psi and about 2000 psi (144 kg f /cm 2 ), preferably between about 500 psi and about 900 psi, and more preferably between 650 psi (45.7 kg f /cm 2 ) and about 750 psi (52.7 kg f /cm 2 ). If an open-cell foam is desired, the curing means is only partially filled and the materials are not pressurized, remaining instead at atmospheric pressure. If desired, an open-celled foam of still greater cell size could be created by curing the material under vacuum (less than atmospheric pressure). To activate the cross-linking and blowing agents the materials are heating in the curing means to a temperature of between about 100 degrees C. and about 500 degrees C., preferably between about 130 degrees C. and about 200 degrees C., and more preferably between about 150 degrees C. and about 175 degrees C. In addition to curing the material with heat, other means of curing, such as microwave or similar irradiation, may be used.
The curing step is a critical step in the process. The temperature, pressure and curing time are adjusted for a particular combination of blowing agent, cross-linking agent, cross-linkable elastomeric polymer, and curing means geometry to vary the rate of cross-linking such that the camouflage piece cures completely and has a visual camouflage appearance throughout its mass and contains substantially no blisters. Blisters are void spaces within the foam that substantially exceed the size of the foam cells. They may be created by blowing agent or air bubbles which become trapped in the polymer during curing. In general, the higher the temperature, the greater is the rate of cross-linking.
The rate of cross-linking and blowing agent decomposition cannot be measured directly. A cone rheometer, however, may be used to analyze an elastomeric specimen. This apparatus allows the measurement of small pressure changes within the polymer while simultaneously measuring the torque necessary to shear the polymer in an oscillatory manner.
Three particularly important features in the curing step are the rate of decomposition of the blowing agent, the rate of cure of the elastomeric polymer, and the rheological properties of the foamed polymer. Variations in rheological properties can be obtained by varying the type and amount of additives used. Particularly advantageous additives may be selected from hundreds known in the art and available in the market.
The relationship between the rate of cross-linking and the blowing agent decomposition rate is crucial to proper curing. If the rate of cross-linking is too slow, the blowing agent will decompose into a high pressure gas before the material has reached an adequate plasticity by cross-linking, which leads to an unacceptable blending or swirling of the colors of the polymer pieces as further cross-linking occurs. On the other hand, if the rate of cure is too fast, the colored pieces will prematurely lose their plasticity, becoming too rigid to adhere together when the blowing agent increases pressure within the material. In this case, when the pressure is released and the material is allowed to expand freely, blisters will be created throughout the material by trapped air or blowing agent bubbles located in the interstices of the pieces.
The relationship between cross-linking rate and blowing agent decomposition rate is illustrated in FIGS. 1 and 2. Curve C and point C1 in FIG. 1 illustrate the relationship between the rate of blowing agent decomposition and cross-linking rate. Curve C indicates a blowing agent which decomposes after most of the cross-linking has already occurred. Thus the material will be too rigid to expand without blistering because of the gases trapped in the interstices of the foam pieces.
An example of a blowing agent and cross-linking curve wherein the material is cross-linked too slowly is provided by Curve A and Point A1 in FIG. 1. Curve A indicates a blowing agent that decomposes very rapidly in the curing process. Thus, at pressure P at time T1, very little cross-linking has occurred as the blowing agent decomposes. Since little cross-linking has occurred, the material is quite fluid, and as the blowing agent decomposes throughout the material, the colors are smeared by small pressure differences among and within the polymer pieces. Smearing is magnified by the heat buildup arising from the exothermic blowing agent decomposition reaction.
By contrast, with the proper selection of polymer, blowing and cross-linking agents, and additives, it is possible to achieve an optimal cross-linking rate for a particular blowing agent decomposition rate in view of the rheological properties of the polymer. This is indicated by Curve B and Point B1 in FIG. 1. Cross linking has progressed to a sufficient point to prevent the polymer pieces from moving with respect to each other as the blowing agent decomposes. It has not, however, progressed too far, and the polymer pieces are sufficiently pliable and display sufficient tackiness to cross-link and adhere properly together without trapping air or gas bubbles. Blistering will not occur, and a visual camouflage appearance will be obtained without a blend or smearing of colors and without blistering.
FIG. 2 illustrates how the rate of cure for a particular compound may be modified with respect to a particular blowing agent system, which includes the blowing agent, blowing agent activator, and other additives selected to affect the curing process such as tackifiers. In Curve E, by the time the blowing agent has decomposed sufficiently to foam the material, cross-linking has already proceeded beyond an excessive stiffening point, and the polymer pieces will be too rigid and insufficiently tacky to cross-link and adhere together without trapping air or gas, leading to blisters. Curve G, on the other hand, illustrates a curing rate which is too slow, as indicated by point D1. At point D1, very little cross-linking has occurred; the material is very fluid, and a blend or swirl of colors with a poor camouflage pattern will be produced by further cross-linking. Curve F, by contrast, illustrates a cross-linking rate which is neither too fast nor too slow; thus, upon decomposition, the blowing agent gases will be dispersed throughout the polymer, and the medium is sufficiently stiff to prevent a swirl or blend of colors as further cross-linking occurs.
After the curing step is complete, the materials in the curing means are decompressed, removed from the curing means, and allowed to cool. The order of the cooling step, however, is not critical and the material may be cooled before being removed from the curing means. The decompression step functions to remove the blowing agent decomposition gases and air bubbles from the polymer and to halt the cross-linking reaction. It also foams the material further as the gases expand the cellular structure created by the blowing agent decomposition.
The foamed material may be removed from the curing means manually or automatically, and the removal may also occur after mechanical or chemical processing occurs, such as drying, cutting or washing.
When the material has cooled sufficiently, the outer skin of the cured, foamed camouflaged material must be removed to reveal the desired camouflage pattern. The skin may be removed by any method known in the art, such as cutting, sliding, or grinding, depending on the shape desired in the final product.
If the elastomeric polymer selected continues to exhibit smearing or blending of colors regardless of cure rates or blowing agent systems selected, the viscosity at cross-linking temperature of the uncured elastomeric polymer should be raised to reduce the tendency of the material to flow at the higher temperature. This may be done by using an uncured elastomeric polymer with a lower Malt Index (higher viscosity) at cross-linking temperature, or by varying the type and amount of additives capable of modifying the rheological properties of the compound, such as plasticizers, tackifiers, and fillers by way of nonlimiting example.
By following the above process together with the above described relationships, one skillful in the art of compounding foams can, without undue experimentation, formulate an acceptable visual camouflage compound with no blistering or smearing of colors from the many materials available in the art, such as blowing agents, activators, plasticizers, polymers, cross-linking agents, etc. The preferred way to obtain the correct formulation is by observing the visual appearance of the cured foamed material to determine if either blisters or smearing of colors has occurred. If so, the formulation should be adjusted according to the above parameters until the desired pattern is obtained without blisters or smearing of colors. A cone rheometer is preferentially used to more accurately control the process.
Prior attempts to obtain such materials like the present camouflage material have not been successful. Some of these attempts have resulted in a poor camouflage appearance, both on the surface of the material and throughout its mass. Other efforts have not produced a noticeable camouflage appearance at all, characterized by randomly sized areas of distinct colors, and being marred by large air pockets, known as blisters. The blister are distributed throughout the material instead of the foam with consistent, uniformly sized foam cells. In both cases the appearance of the material renders it commercially unviable.
The following Examples are given to illustrate the invention, but are not to be limiting thereof. All percentages given throughout the specification are based upon weight of the base polymer or polymers used unless otherwise indicated and total 100% of the final product.
EXAMPLE 1
This Example demonstrates the preparation of a camouflage material according to the invention. The following materials were used in the amounts recited:
______________________________________ Parts By WeightMaterial Object A Range______________________________________Ethylene vinyl acetate Elastomeric polymer 100 100(18% vinyl acetatecontent)Natural Rubber Viscosity modifier 5 5-20Aluminum Silicate Active filler to 10 0-20 reinforce and to increase viscosityCalcium Carbonate Inert filler to lower costs 10 0-50 costs and increase viscosityDicumyl peroxide Cross-linking agent 1 0.5-1.5Azodicarbonamide Blowing agent 6 0.1-10Zinc Oxide Blowing agent activator 5 1-8 to accelerate decomposition rateStearic Acid Dispersion agent 1 1-3Strukol 60 NSF Tackifier; homogenizes 3 0-6 and improves cell qualityColoring Agents To impart camouflage 1 0.1-5 colors______________________________________ Column A shows parts by weight for Example 1 Range Column shows an acceptable, nonlimiting range for each for each additive to illustrate their effects
A batch of foamable polymer is prepared separately for each color desired in the final material by weighing the polymer, blowing agent, cross-linking agent, coloring agent, and other materials and mixing them separately by conventional methods, for example a Banbury mixer, mixing mills, or other methods known in the art, to obtain different batches of colored, uncured elastomeric polymer compound. Each colored batch is then formed into pieces of a specific and proportional size, shape, and weight, according to the final camouflage pattern desired.
For this example, a batch for each of four colors was compounded separately in a Banbury mixer and calendared to form thin sheets of different colors: black, dark green, light green, and beige. To obtain pieces of differing sizes and shapes, a rotary cutter with a variable knife speed and cutting angle were used. By this means, there may be obtained pieces with a wide range of shapes and sizes, such as squares, rectangles, trapezoids or narrow strips. In this example, narrow strips were cut in the following sizes: black, 800×25×0.6 mm.; dark green, 800×25×1.8 mm; light green, 800×25×1.8 mm; beige, 800×25×1.8 mm.
The colored pieces were then arranged lengthwise forming groups in the following pattern: one light green, 1 black, 1 beige, 1 black, one light green, one black, and 1 dark green. This ratio corresponds to the final desired camouflage pattern of 40 percent light green, 20 percent dark green, 20 percent beige, and 20 percent black.
This ratio was used to obtain a realistic sylvan camouflage pattern. A flat compression mold 900×600×9 mm was filled with 5.5 kilograms of the compound according to the above arrangement. The preferred way of curing the compound is by compression molding. The curing parameters used were 60 kilograms force per centimeter squared (60 kg f /cm 2 ), 165 degrees centigrade (C), and a 12 minute batch curing time. At the beginning of the cycle, the mold was pressure-purged by applying a pressure of 60 kg f /cm 2 to the mold and releasing it to remove trapped air from the compound. The pressure of 60 kg f /cm 2 was reapplied, the material was heated to 165° C., and the compound was cured for 12 minutes, during which time the blowing agent decomposed. The pressure was then released, allowing the cured polymer to expand, and the material was removed from the mold and cooled.
This process yielded a micro-cellular expanded foamed slab with no blisters and no smearing of colors. Other suitable methods of curing, such as rotocuring, may be used without departing from the scope of the invention. The final appearance of the slab was also evaluated by removing a thin sheet 1.5 millimeters in thickness, which was sliced from the slab with a splitting machine. The surface of the internal material exhibited a camouflage effect with no blistering and no smearing of colors. The sample material was used to fabricate bottle protectors, masks, to cover helmets, canteens, and boats. The material was readily moldable and easily applied to other objects.
EXAMPLE 2
A second batch of foamed polymer was prepared using identical amounts of all components except dicumyl peroxide (the cross-linking agent), which was used at 0.5 parts instead of 1 part. The identical procedure was followed to create a foamed polymer which exhibited a smearing of colors. This is in accordance with the disclosed relationship between the rates of cross-linking and blowing agent decomposition. The slower cross-linking rate resulted in a material having relatively little cross-linking as the blowing agent decomposed. As a consequence, the colors were smeared by small, localized pressure differences within and among the polymer pieces.
EXAMPLE 3
A third batch of foamed polymer was prepared using identical amounts of all components in Example 1 except dicumyl peroxide (the cross-linking agent), which was used at 2 parts by weight instead of 1 part. A procedure identical to that for Example 1 was followed, yielding a batch of polymer with high levels of blisters in the material, in accordance with the disclosed relationship between the rates of cross-linking and blowing agent decomposition. The faster cross-linking rate resulted in a material having a relatively great amount of cross-linking as the blowing agent decomposed. Consequently, the material was relatively rigid at the point of blowing agent decomposition, creating pockets of trapped gas which were not dispersed throughout the medium. Upon depressurization, these gas pockets created blisters.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention and all such modifications are intended to be included within the scope of the following claims. | A foamed elastomeric polymer with a camouflage appearance on its surface and throughout its mass, characterized by distinct, randomly sized regions of various colors, having curved, nonangular borders with substantially no blend of colors, and being free from gas pockets and blisters. A process for manufacturing a foamed elastomeric polymer of the above description. | 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 beach and shoreline renourishment. More specifically. the invention comprises a modular water-permeable fence assembly designed to impede the flow of suspended particles—thereby producing sand accretion. A method for deploying the fence assembly is also disclosed.
2. Description of the Related Art
Beach and shoreline erosion is a recognized problem in many areas. Erosion and accretion are natural processes whereby shorelines advance and retreat over time. Where structures are erected on the shoreline, however, the natural erosion jeopardizes property having substantial economic worth.
Various methods have been used to impede or prevent beach erosion. It has long been known that suspending a mesh or net in the water near the beach tends to cause an accumulation of sand in the region of the net. One such device is disclosed in U.S. Pat. No. 3,564,853 to Csiszar (1969) Another approach based on the same concept is disclosed in U.S. Pat. No. 4,089,179 to Trautman (1978). Both these inventions require the deployment of supporting pilings or anchors a considerable distance offshore.
In recent years, efforts have focused on the use of fence structures arrayed in a direction perpendicular to the beach. One such fence structure is disclosed in U.S. Pat. No. 4,710,056 to Parker (1987). The Parker device uses a line of flexible mesh suspended from evenly spaced supports. The supports are actually three-legged structures, with each leg being driven or buried in the sand at an angle for added stability. While the Parker device does succeed in accumulating sand, the mesh employed tends to become buried. Both the buried mesh and the submerged portions of the support legs become exceedingly difficult to remove. The tendency of the fence structures to become submerged and stuck within the sand they accumulate is, in fact, one of the most significant recognized problems with this approach.
U.S. Pat. No. 5,255,997 to Bailey et.al. (1993) provides an excellent explanation of this self-burial phenomenon. FIG. 11 of the Bailey disclosure illustrates mesh panels capable of sliding up and down on their supporting poles. As the text explains, the panels tend to sink within the deposited material (river mud), until their downward progress is checked by restraining straps.
A device which is capable of adjusting the height of the mesh deployed is disclosed in U.S. Pat. No. 5,720,573 to Benedict et.al. (1998). As seen in FIG. 1, the Benedict device incorporates a rigid horizontal rod which spools up the mesh fabric and prevents unwanted immersion in the accumulated sand. Several versions are disclosed, including one where the height of adjacent mesh panels is adjustable somewhat independently (see FIG. 14). FIG. 15 of the Benedict disclosure shows mesh panels mounted in a rigid frame. These panels can presumably be raised and lowered with respect to the support pilings. It is important to realize, however, that the panels are subject to considerable force from wave impact. Ideally the waves travel in a direction which is perfectly perpendicular to the fence, but this is often not the case. It is therefore important to secure the fence panels to the support pilings so that the panels cannot bend and thereby escape the securing device. The arrangement shown in the '573 disclosure obviously does not address this concern. In addition, the '573 disclosure requires the use of bulky external brackets to the support pilings.
FIG. 17 of the '573 disclosure is generally instructive regarding the use of fence structures, as it shows a plan view of several fence structures deployed along a shoreline. The array illustrated is typical of how these devices are used; i.e., a series of several fence structures is needed.
Accordingly, the prior art devices are limited in that they:
1. Require the deployment of pilings or support structures a considerable distance from shore;
2. Do not provide means for preventing the burial of the fence material used,
3. Are insufficiently rigid to resist wave forces; and
4. Require the addition of external brackets on the pilings.
BRIEF SUMMARY OF THE INVENTION
The present invention comprises a beach renourishment sand snare and a method for its employment. A series of metal posts are embedded in the sand, forming a line which is approximately perpendicular to the shore. Each post has a pair of slots cut vertically down its side, with the slots all lining up in a direction which is perpendicular to the shore. Semi-rigid mesh panels are constructed of polymer coated wire mesh. Each side of the mesh panel is enclosed in a clamping assembly. Each clamping assembly is configured to slide into the slots cut into the posts, with means provided to secure the clamping assembly in place in the slot. Thus, a mesh panel may be lowered into place and secured between adjacent posts by sliding the clamping assemblies on either side of the mesh panel into the slots in the two adjacent posts.
A method of applying the sand snare is also disclosed. The placement of the mesh panel in the surf tends to accumulate sand around the panel. The sand will eventually accumulate to the point that the shoreline will advance seaward of the mesh panel. Because each mesh panel is independently placed, once the shoreline has advance past its position, that panel can be removed and transferred to the seaward end of the line of posts. Likewise, the posts on the landward side can be removed and transferred to the seaward side once they are no longer needed—thereby extending the line of posts. In this fashion, a series of posts and mesh panels can be “walked” into the sea, accumulating sand and advancing the shoreline indefinitely.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is an isometric view, showing the wire mesh material.
FIG. 2 is an isometric view, showing the wire mesh in greater detail.
FIG. 3 is an isometric view, showing the application of the clamping assemblies to the wire mesh panel.
FIG. 4 is an isometric view, showing how the brackets are affixed to the mesh panel
FIG. 5 is an isometric view, showing the completed panel assembly.
FIG. 6 is an isometric view, showing a post.
FIG. 7 is an isometric view with a cutaway, showing the rear base.
FIG. 8 is a perspective view, showing how a panel assembly slides into adjoining posts.
FIG. 9 is a perspective view, showing how a panel assembly slides into adjoining posts.
FIG. 10 is a top view of the clamping assembly held within the post.
FIG. 11 is an isometric view, showing the application of the device to renourish a beach.
FIG. 12 is an isometric view, showing the renourishment process.
FIG. 13 is an isometric view, showing the renourishment process.
FIG. 14 is an isometric view, showing the renourishment process.
FIG. 15 is an isometric view, showing the renourishment process.
FIG. 16 is an isometric view, showing the renourishment process.
FIG. 17 is an isometric view, showing the renourishment process.
FIG. 18 is an isometric view, showing the preferred embodiment.
FIG. 19 is an isometric view, showing the installation of the preferred embodiment in a post
FIG. 20 is a top view, showing the installation of the preferred embodiment in a post
REFERENCE NUMERALS IN THE DRAWINGS
10
mesh panel
12
vertical rod
14
horizontal rod
16
welds
18
back bracket
20
jacking bracket
22
jack member
24
jack brace
26
fastener hole
28
female rivet
30
male rivet
32
post
34
slot
36
tube brace
38
panel assembly
40
clamping assembly
42
water
44
low tide line
46
accumulation zone
48
alternate back bracket
50
alternate jacking bracket
DETAILED DESCRIPTION OF THE INVENTION
Those skilled in the art are aware that suspending a mesh material in the sand-laden water near a beach causes the suspended sand particles to fall out of suspension and accumulate on the bottom Flexible mesh materials have traditionally been used for this purpose, such as nylon nets similar to those used for fishing.
As the sand accumulates over the lower portions of the mesh material, the material becomes imbedded. Flexible netting is often difficult to remove, since the force necessary to pull the netting out of the sand is often sufficient to catastrophically tear the netting. Accordingly, the present invention employs a much more rigid mesh material. FIG. 1 shows a portion of a mesh panel 10 . The reader will observe that it is composed of evenly spaced vertical rods 12 joined to evenly spaced horizontal rods 14 .
FIG. 2 shows mesh panel 10 in greater detail. It is generally composed of steel wire having a diameter between 0.030 and 0.125 inches. The array of horizontal and vertical rods are joined by a series of welds 16 . Of course, mesh panel 10 is ultimately destined to be immersed in salt water. It is therefore critical that mesh panel 10 be coated with a corrosion inhibiting substance. One particularly effective method is to coat the completed weldment with synthetic rubber or other flexible and stable polymers. Those skilled in the art will realize that this technique is now employed in the construction of crab traps and the like. The coating prevents the salt water from contacting the metal, yet remains flexible so the coating will not fracture as the mesh twists.
FIG. 3 shows the assembly of several components. Mesh panel 10 is generally rectangular, having a lower edge, an upper edge, a first side edge, and a second side edge. The first side edge (to the left in the view as shown) is sandwiched between a back bracket 18 and a jacking bracket 20 . Likewise, the second side edge is also sandwiched between a back bracket 18 and a jacking bracket 20 . The reader will observe that the relative positions of the two brackets are transposed on opposite ends of mesh panel 10 . The reason for this will be explained subsequently.
FIG. 4 illustrates one method for joining the brackets to mesh panel 10 . Back bracket 18 and jacking bracket 20 are both pierced by a series of fastener holes 26 . When the two brackets are placed on opposite sides of mesh panel 10 as shown, these holes align. The holes also align with gaps between the rods comprising mesh panel 10 . One method of joining the two brackets to mesh panel 10 is placing rivets within the fastener holes 26 and crimping the rivets in place. Female rivet 28 and male rivet 30 are shown in the appropriate position for insertion. Those skilled in the art will appreciate that many other conventional fastening methods could be used—such as spot welding or crimping.
FIG. 5 shows the completed panel assembly 38 . Each set of back bracket 18 and jacking bracket 20 , along with any associated fasteners, is referred to as clamping assembly 40 . The reader will observe that both side edges of mesh panel 10 are clamped securely within a clamping assembly 40 . In this state, mesh panel 10 may flex somewhat, but it is sufficiently stiff to prevent folding
It is desirable to use identical brackets on the first side edge and the second side edge of mesh panel 10 . It is therefore necessary to swap the respective positions of back bracket 18 and jacking bracket 20 on the second side edge with respect to the first side edge. In FIG. 5, the clamping assembly 40 on the left side of the view has jacking bracket 20 in the foreground and back bracket 18 in the background. The clamping assembly 40 on the right side of the view has back bracket 18 in the foreground and jacking bracket 20 in the background.
Those skilled in the art will realize that once a particular mesh panel 10 has been in position for several days, its bottom edge will be mired in the accumulated sand. It often requires considerable force to lift mesh panel 10 clear. It is therefore advisable to have designated lift points attached to mesh panel 10 . The user can then manually apply force to these lift points or, in the alternative, apply a jacking mechanism.
Returning now to FIG. 4, the lift points will be explained. The reader will observe that the upper portion of jacking bracket 20 has jack member 22 welded to it at a right angle. The purpose of jack member 22 is to provide a horizontal surface to which a lifting force can be applied. Jack brace 24 is provided to reinforce jack member 22 . The addition of these elements causes jacking bracket 20 to be taller than back bracket 18 . Returning to FIG. 5, the reader will observe that each end of panel assembly 38 is provided with a lift point (though on opposite sides of the panel).
FIG. 6 shows post 32 . Post 32 is typically a hollow metal cylinder. As it must be immersed in salt water, it is advisable to fabricate this element from aluminum or coated steel. The lower portion of post 32 will be driven or dug into the sand during the installation process. The upper portion opens into a pair of vertical slots 34 . Those skilled in the art will realize that the addition of vertical slots 34 significantly weakens the structure of post 32 . Turning now to FIG. 7, the reader will observe that three tube braces 36 have been added to address this concern. Each tube brace 36 fits within a hole drilled through post 32 from side to side. Once in position, each tube brace 36 is welded in place. A similar result could be obtained using a threaded rod with accompanying nuts and washers. The intent is to reinforce the upper portion of post 32 , but the actual method of carrying out this reinforcement is not significant to the present invention.
FIG. 8 illustrates the installation of a panel assembly 40 within a pair of adjacent posts 32 . The two clamping assemblies 40 on either end of panel assembly 38 slide into the slots 34 in the two posts 32 . Panel assembly 38 is then lowered in the direction indicated by the arrows. FIG. 9 shows the same assembly with panel assembly 38 in the fully installed position.
FIG. 10 shows the left hand post 32 from the top. This view readily illustrates how clamping assembly 40 engages slot 34 . The reader will recall that both back bracket 18 and jacking bracket 20 are formed of angle iron (in the shape of the letter “L”). When viewed from the top, each bracket contains a flange which is parallel to mesh panel 10 and a flange which is perpendicular to mesh panel 10 . The perpendicular flanges obviously play an important role, as they bear against the interior cylindrical surface of post 32 .
Mesh panel 10 is often subjected to substantial lateral wave forces (from top to bottom or from bottom to top in the view as shown). When this occurs, mesh panel 10 comes under significant tension. This tension is transmitted to post 32 by the two flanges (of the two brackets) which extend perpendicularly outward from the plane of mesh panel 10 . These perpendicular flanges bear against the interior of post 32 . Thus, even under substantial lateral wave forces, mesh panel 10 is unable to pull free of post 32 .
The embodiment shown in FIG. 10 places the material of mesh panel 10 in direct contact with slot 34 in post 32 . This results in the coating on mesh panel 10 rubbing against the metal of the vertical walls of slot 34 during heavy wave action. The protective coating may eventually rub off under this wave action, causing accelerated corrosion of mesh panel 10 .
The inventor solved this problem by creating an alternate embodiment which has now become the preferred embodiment. FIG. 18 shows this preferred embodiment. The reader will observe that alternate back bracket 48 and alternate jacking bracket 50 are similar to back bracket 18 and jacking bracket 20 , with one important exception: the flange on each bracket which is parallel to the plane of mesh panel 10 extends toward the center of mesh panel 10 rather than away from the center of mesh panel 10 (compare particularly FIGS. 4 and 18 ).
FIG. 19 shows the installation of a panel assembly using alternate back bracket 48 and alternate jacking bracket 50 in slot 34 of post 32 . Using this configuration. there is no contact between mesh panel 10 and the walls of slot 34 . Thus, the abrasion damage to mesh panel 10 is largely eliminated.
FIG. 20 shows the same assembly from above. In this view, one may more readily observe how the flanges of alternate back bracket 48 and alternate jacking bracket 50 extending in a direction parallel to mesh panel 10 serve to prevent mesh panel 10 from bearing directly against the vertical walls of slot 34 . The other features of the two alternate brackets—such as the jacking member—are essentially identical to those features found on the original brackets. Those skilled in the art will appreciate that the fasteners used to join alternate back bracket 48 and alternate jacking bracket 50 together must lie flush with the surfaces of the brackets. Otherwise, the portions of the fasteners which protrude would prevent the device from sliding into slot 34 .
The method of applying the original device disclosed in FIGS. 1 through 10, or the preferred embodiment disclosed in FIGS. 18 through 20, is the same. FIG. 11 illustrates a typical shoreline. Water 44 meets the sand of the beach at low tide line 44 . Waves have not been illustrated for purposes of simplicity. However, it is important to keep in mind that waves of varying sizes will typically be approaching the beach from right to left in the view as shown.
A line of posts 32 is embedded in the sand as shown. These posts start to the landward of low tide line 44 and extend to seaward (to the right in the view as shown) out into the water. Several panel assemblies 38 are placed between posts 32 as described previously. Although only a single fence structure is illustrated, those skilled in the art will realize that the structure illustrated is one of a series of such structures arrayed along the beach. Each line of fencing is typically separated by 30 to 200 feet of open space.
As the tide comes in the series of panel assemblies 38 will become partially submerged. The mesh panel 10 within each panel assembly 38 will tend to cause sand particles suspended in the water to fall out of suspension and accumulate on the bottom. FIG. 12 shows the result of this process. The reader will observe that low tide line 44 has moved to seaward in the vicinity of the fence structure. This region is designated as accumulation zone 46 .
The panel assemblies 38 are free to be raised progressively with respect to the line of posts 32 as the sand accumulates. It is also possible to provide means for holding them at a fixed elevation. Practical experience has shown, however, that simply pulling the bottom edge of each panel assembly 38 free of the sand and allowing it to rest again on the sand provides an efficient method of height adjustment without resort to mechanical fixing means. Under optimum sand deposition conditions, this raising of the panel assemblies must be performed every few hours. If the raising operation is not performed regularly, then some panel assemblies 38 may become mired such that the user is incapable of lifting them free. In that case, mechanical jacking devices are applied to the jacking points on each panel assembly 38 to lift them free.
Those skilled in the art will realize that once sand has accumulated to the point shown in FIG. 12, the panel assembly 38 on the left hand extreme (in the view) of the line of posts can be removed and transferred to the right hand end of the line. Each panel assembly 38 is sufficiently rigid and light to be removed, carried, and reinstalled by one person under most circumstances.
FIG. 13 shows the same fence assembly after one panel assembly 38 has been removed from the left end of the line and added to the right end. Meanwhile, accumulation zone 46 has extended further to the right.
FIG. 14 shows the same fence structure after another panel assembly 38 has been transferred from left to right. At this point, the two posts 32 furthest to landward are no longer needed. Accordingly, these two posts 32 are removed and added to the seaward end of the line (to the right in the view).
In FIG. 15 the process has continued with the removal and transfer of another post 32 and another panel assembly 38 . The deposition process has continued to move accumulation zone 46 to seaward. The process of transferring panel assemblies 38 has continued in FIG. 16 .
Eventually, low tide line 44 will have been moved seaward to the desired position. The reader must keep in mind that the fence structure shown is one of numerous such structures in parallel. If left in a fixed position, the undulations in low tide line 44 tend to smooth into a uniform shoreline. FIG. 17 illustrates this result. Once the shoreline has stabilized, the entire fence structure is removed—leaving the natural beach.
The reader will therefore appreciate that the modularized nature of the fence structure disclosed allows a user to “walk” the structure out into the sea as the shoreline advances. In this way, the need for extended and unsightly fencing structures is eliminated. The invention has additional advantages in that it:
1. Does not require the deployment of pilings or support structures a considerable distance from shore;
2. Provides means for preventing the burial of the fence material used,
3. Is sufficiently rigid to resist wave forces;
4. Does not require the addition of large external bracket structures on the pilings,
5. Is modular in nature, allowing the fence structure to be “walked” to seaward as the sand accumulates; and
6. Transmits tensile loads placed on the mesh to the posts.
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. Thus, the scope of the invention should be fixed by the following claims, rather than by the examples given. | A beach renourishment sand snare and a method or its employment. A series of metal posts are embedded in the sand, forming a line which is approximately perpendicular to the shore. Semi-rigid mesh panels are slidably placed and secured between adjacent posts. Each mesh panel, once immersed in the surf, tends to acumulate sand. The sand will eventually accumulate to the point that the shoreline will advance seaward of the mesh panel. Once this occurs the particular mesh panel is removed and transferred to the seaward end of the line of posts. Likewise, the posts on the landward side can be removed and transfered to the seaward side, thereby “walking” the assembly to seaward. The process thereby accumulates sand and advances the shoreline. | 4 |
CROSS REFERENCES TO PRIORITY APPLICATIONS
This application is a continuation of U.S. Utility patent application Ser No. 10/060,975 filed Jan. 30, 2002, now issued as U.S. Utility Pat. No. 6,928,295, which claims priority to U.S. Provisional Patent Application No. 60/264,993 filed Jan. 30, 2001, which is incorporated herein by reference in its entirety.
1. FIELD OF THE INVENTION
The present invention relates to wireless communications; and more particularly to wireless network communications.
2. BACKGROUND OF THE INVENTION
The number and popularity of wireless communications devices in use continues to rise rapidly all over the world. Not only are mobile phones very popular, but there is also a demand for wireless networking devices. One standard for wireless networking, which has been widely accepted, is the Specification of the Bluetooth System, v. 1.0 (“Bluetooth Specification”). The Bluetooth Specification continues to evolve and subsequent versions are expected to be available.
The Bluetooth Specification enables the creation of small personal area networks (PAN's), where the typical operating range of a device is 100 meters or less. In a Bluetooth system, the wireless Bluetooth devices sharing a common channel form a piconet. Two or more piconets co-located in the same area, with or without inter-piconet communications, is known as a scatternet. It is anticipated that as piconets are setup there could be several piconets operating in the same area as a scatternet, but not necessarily linked together.
The need to have security procedures in wireless networks has led to security, encryption and authentication procedures and protocols being incorporated as part of the Bluetooth Specification, in Volume 1, part B, Section 14: Bluetooth Security, of the Specifications of the Bluetooth System, v. 1.0, as referenced above.
When a wireless Bluetooth device tries to connect to a particular piconet, it must go through an authentication process, where a user that is part of that piconet, allows the guest to join the piconet. Typical wireless network devices such as computers, personal digital assistants (PDAs) and mobile phones, have a display and a keyboard that facilitate the authentication process. When a user with a mobile phone enters into the operating range of a piconet, he will get a message telling what piconet, with a particular ID, he has just entered and he can signal his intention to join that piconet by pressing the appropriate key on his keypad. When he presses the appropriate key, he will start the process of joining that piconet.
When the guest entered into range of the piconet, his PIN was sent to and received by the devices in the piconet. His PIN can then be shown on the displays of the devices in the piconet. A user in the piconet can then respond to the guest's request and he can accept or deny the guest's request to join that piconet. Eavesdropping during the registration process makes Bluetooth devices particularly vulnerable to security breaches.
When a guest enters an area with several operating piconets, his display will show him the ID's of the piconets he has discovered. The guest can then choose which piconet to join using his keypad. But when the guest has a minimal user interface, such as a wireless headset, he has not ability to signal his choice of which piconet to join. In such case, the headset may be paired to work only with a paired device. This paired device may also have a limited user interface, and not have a display or keypad.
There is a need for a system, protocol and procedure to enable wireless devices, such as headsets, to join a particular piconet. There is also a need to improve security by reduce the possibility of eavesdropping on the authentication process. There is also a need to avoid burdening nearby nodes with the extra traffic caused by authentication.
SUMMARY OF THE INVENTION
The present invention is directed to apparatus and methods of operation that are further described in the following Brief Description of the Drawings, the Detailed Description of the Drawings, and the Claims. Other features and advantages of the present invention will become apparent from the following detailed description of the invention made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates in a block diagram, a point-to-point network between two wireless devices;
FIG. 2 illustrates in a block diagram, a point to multipoint network among a plurality of wireless devices;
FIG. 3 illustrates in a block diagram, a scatternet that includes multiple piconets with overlapping coverage;
FIG. 4 is a system diagram illustrating a scatternet in which one operation according to the present invention is performed;
FIG. 5 is a logic diagram illustrating operation according to the present invention; and
FIG. 6 is a block diagram generally illustrating the structure of a wireless device constructed according to the present invention.
DETAILED DESCRIPTION
FIG. 1 illustrates a network 10 that includes two wireless devices 102 - 1 and 102 - 2 . Network 10 is, for example, a wireless Bluetooth point-to-point piconet where wireless device 102 - 1 is a master Bluetooth system and wireless device 102 - 2 is a slave Bluetooth system, where the master 102 - 1 and slave 102 - 2 share the same channel. The point-to-point network 10 described with reference to FIG. 1 need not include Bluetooth devices 102 - 1 , 102 - 2 , but, rather, may comprise any type of wireless device. These wireless devices 102 - 1 and 102 - 2 may include digital computers, computer peripherals such as printers, scanners, mice, keyboards, etc., personal data assistants (PDAs), wireless telephones, wireless headsets, and other wireless devices.
FIG. 2 illustrates a network 20 that includes a plurality of wireless devices 102 - 1 , 102 - 2 . . . 102 - i . . . 102 - n (2≦i≦n). Wireless network 20 is, for example, a point-to-multipoint Bluetooth piconet where wireless device 102 - 1 is a master Bluetooth system and wireless devices 102 - 2 through 102 - n are slave Bluetooth systems and communicate with the master Bluetooth system 102 - 1 over the same channel. In at least one embodiment, up to seven slaves can be active in the piconet 102 . The number of active slaves supported in a piconet depends on many variables and design considerations. The point-to-point network of FIG. 2 need not include Bluetooth devices 102 - 1 , 102 - 2 , but, rather, may comprise any type of wireless device.
In addition to the active slaves 102 - 2 , 102 - i through 102 - n illustrated in FIG. 2 , a point-to-multipoint piconet 20 may include many additional slaves that can remain locked to the master 102 - 1 in a so-called “parked” state. When a slave does not need to participate on the piconet channel, but still needs to remain synchronized to the channel it can enter the parked state. These parked slaves cannot be active on the piconet channel, but still remain synchronized to the master.
For both active and parked slaves in a single piconet 20 (or piconet 10 of FIG. 1 ), the master 102 - 1 controls channel access. To this end, the master 102 - 1 switches control from one slave to another as it controls channel access within the piconet 20 . The master 102 - 1 identifies each slave through a unique network address assigned to each slave. When a transfer of information between two slaves in a piconet 10 is desired, the master 102 - 1 coordinates point-to-point transmission between the two slaves.
Referring to FIG. 2 , for instance, slave 102 - 2 could be a wireless personal digital assistant (“PDA”) device equipped with a Bluetooth system and slave 102 - i could be a wireless cellular telephone equipped with a Bluetooth system. In such a case, the master 102 - 1 can coordinate communications between two slaves 102 - 2 , 102 - i over the piconet channel to exchange, for instance, phone number information. To do so, the master 102 - 1 switches focus between the first slave 102 - 2 , commanding it to transmit phone number data to the master 102 - 1 , and the second slave 102 - i , commanding it to receive phone number data from the master 102 - 1 . This switch in focus is performed by the master through its storing and accessing context information regarding each slave in a relatively rapid succession.
FIG. 3 , illustrates, for instance, a “scatternet”, formed from multiple piconets with overlapping coverage. Bluetooth piconets 20 , 31 , 33 , and 37 form part of the larger Bluetooth scatternet 30 . Each piconet 20 , 31 , 33 , and 37 has only a single master 102 - 1 , 36 , 36 , and 34 respectively. However, FIG. 3 also illustrates that slaves can participate in multiple piconets on a time-division multiplex basis. For instance, in FIG. 3 , slave 32 participates in two piconets: piconet 20 having master 102 - 1 and piconet 31 having master 36 . In addition, a master 34 in one piconet 33 can be a slave in another piconet 37 . Further, a single Bluetooth system may serve as a master in two piconets, e.g., Bluetooth system 36 serves as a master in both piconet 31 and piconet 37 .
FIG. 4 is a system diagram illustrating a scatternet in which one operation according to the present invention is performed. The scatternet of FIG. 4 includes four separate piconets 402 , 404 , 406 , and 408 . Piconet 402 includes master (computer) 410 , slave 412 (PDA), and slave 414 (printer). Piconet 404 includes master 420 (computer), slave 422 (PDA), and slave 423 (wireless phone). Piconet 406 includes master (computer) 416 , slave 418 (PDA), and slave 414 (printer). Piconet 408 includes master (computer) 424 , slave 426 (PDA), and slave 428 (wireless phone). The four separate piconets 402 , 404 , 406 , and 408 have overlapping coverage areas. In the embodiment of FIG. 4 , all masters are shown to be computers because they will typically be stationary and have the processing capability to service a number of slaves. However, in other embodiments, the masters could be other devices as well. The scatternet of FIG. 4 may service a call center, customer service department, or other office environment, for example that benefits by the wireless interconnection of the illustrated devices.
A user of wireless headset 430 desires to have the wireless headset 430 join piconet 402 (corresponding to his home computer). The wireless headset 430 has a minimal user interface, e.g., a single authenticate button that initiates joining of a piconet. However, the wireless headset 430 , in its operating location, resides within the service coverage area of each of the four separate piconets 402 , 404 , 406 , and 408 that form the scatternet. According to prior techniques, the user of the wireless headset 430 would have difficulty in selecting the desired piconet 402 because of the minimal user interface components of the wireless headset 430 .
Thus, according to the present invention, when the wireless headset 430 enters (or powers up in) an area with more than one functioning piconet, the wireless headset 430 uses physical proximity, an authenticate button and a power down procedure to start the authentication process. The user of the wireless headset 430 physically approaches within close proximity, e.g., less than one meter, the master 410 servicing the piconet 402 that he wishes to join. Then, the user presses the authenticate button, signaling his intention to join the particular piconet 402 .
Once the authenticate button has been pushed, both nodes, the master 410 and the slave 430 power down to a level that is usable within the one meter close proximity range. In the described embodiment, power down mode will work only if the distance between the devices is less than 1 meter. Power down mode increases the security of the authentication process, by minimizing message traffic, which could be received by other devices and other piconets. Power down mode increases the security of the authentication process, by preventing most other devices in the area from snooping or eavesdropping on the authentication process. Further, power down mode minimizes or eliminates any confusion regarding which piconet that the user wishes to join.
By minimizing air traffic during authentication, the other users and piconets have a better chance of maintaining stable communication. For example, if a piconet were hit with a lot of message traffic from users just walking by the piconet, scarce processing and power resources could be wasted in evaluating the new message traffic. This could bring regular traffic in the piconet to a standstill. Power down mode thus prevents the devices that are now out of range, from being disturbed by the authentication process.
In one operation of the present invention, the user on the piconet 402 that is within close proximity will get a message on the display of the master 410 . The message would typically display the PIN of the guest 430 trying to join the piconet 402 along with a message stating his request to join. The user on the piconet 402 would then either allow or disallow the guest 430 attempting to join the piconet 420 .
Authentication granted by the process could be temporary or permanent. When authentication is complete, then a confirming message can be sent to both devices. The wireless headset 430 user could receive a confirming tone to indicate completion of authentication. If authentication is not successful, that could also generate a message to one or both of the devices 410 and 430 . Once authentication is complete, then normal power mode can be resumed and the guest (wireless headset 430 ) is now part of that piconet 402 and normal communications continue.
FIG. 5 is a logic diagram illustrating operation according to the present invention. The logical operations described with reference to FIG. 5 will include references to the devices of FIG. 4 . Operation commences when a guest (wireless handset 430 ) is placed within close proximity of a master (computer 410 ), e.g., 1 meter (step 502 ). With the guest 430 in close proximity to the master 410 , a user of the guest 430 presses an authenticate button to initiate the joining of a piconet 402 serviced by the master 410 (step 504 ). The master 410 and the guest 430 then enter a power down mode in which the transmit power of each device is reduced (step 506 ). The transmit power during the power down mode is such that devices outside of the proximate distance between the devices 410 and 430 cannot eaves drop upon the authentication operations unless they are also proximately located. Thus, during the power down mode operations, the guest 430 should not be proximately located to other master devices.
Authentication operations are then performed in the power down mode (step 508 ). If the authentication operations are successful (as determined at step 510 ), normal power operations are resumed (step 512 ) and wireless communication operations are serviced until completion (step 514 ) at which point operation ends. If the authentication operations are not successful (as determined at step 510 ), operations end. After a successful authentication operation, confirmation of such success may be communicated to the user of the guest 430 , e.g., the delivery of a distinctive tone to the user of the wireless headset 430 .
FIG. 6 is a block diagram generally illustrating the structure of a wireless device constructed according to the present invention. The general structure of the wireless device 600 will be present in any of the wireless devices illustrated in FIGS. 1-4 , either master devices or slave devices. The wireless device 600 of FIG. 6 implements the operations of FIG. 5 . The wireless device 600 includes a plurality of host device components 602 that service all requirements of the wireless device 600 except for the wireless requirements of the wireless device 600 . Of course, operations relating to the wireless communications of the wireless device 600 will be partially performed by the host device components 602 .
Coupled to the host device components 602 is a Radio Frequency (RF) interface 604 . The RF interface 604 services the wireless communications of the host device 600 and includes an RF transmitter 606 and an RF receiver 608 . The RF transmitter 606 and the RF receiver 608 both couple to an antenna 610 . The teachings of the present invention are embodied within the RF transmitter 606 of the RF interface 604 and are generally referred to as reduced power authentication operations. During these operations, the transmit power of the RF transmitter 606 is reduced to effectively reduce the operating range of the RF interface 604 . During these reduced power operations, the operations of the RF receiver 608 may remain unchanged.
The invention disclosed herein is susceptible to various modifications and alternative forms. Specific embodiments therefore have been shown by way of example in the drawings and detailed description. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the claims. | A system and method for facilitating the authentication of wireless devices in an environment with multiple wireless networks. A user wishing to join an operating wireless network can bring his wireless device within close physical proximity, for example, less than one meter, of a device in the network that he wishes to join. The user then presses an authenticate button, which causes both devices to enter a low transmission power mode. In such case, the devices are only capable of operation within the close proximity. Being in low power mode will diminish the possibility of eavesdropping on the authentication process. Power down mode also reduces the amount of message traffic in the area and saves scarce power and processing resources at the nodes, which are now out of range. Authentication then takes place in low power mode and once completed, both devices resume normal power levels and continue communicating normally. | 7 |
TECHNICAL FIELD
The invention relates to an automobile heater, and more particularly to a supplementary heater for generating heat during initial start-up period of the vehicle prior to heating by the HVAC system.
BACKGROUND OF THE INVENTION
Currently, vehicles use heat from the engine as transmitted from the engine cooling system to the heater core located in the HVAC air handling system to warm the passenger compartment and defrost the windows. Current HVAC systems have a delay time in the production of heat to the passenger compartment. Additional sources of heat are desirable to augment the current vehicle HVAC system.
In vehicles with automatic temperature control (ATC) systems, it is desirable to utilize a supplemental heat system that fills the time delay between vehicle start up and ATC on-time, which is usually one to three minutes and controlled by or is a function of coolant temperature.
There have been various methods proposed for heat augmentation or supplementation to the HVAC system. For example, a first type of heat augmentation is a fuel fired pre-heater. The separate vehicle heating system consists of a heat exchanger, electrical control system, engine coolant water pump, vehicle fuel burner, and a fuel supply line is utilized.
A second type of heat augmentation includes electric heaters utilizing electric heating elements or coils as disclosed in U.S. Pat. No. 3,440,398 issued Apr. 22, 1969, in the name of Nilssen.
A third type of heat augmentation is a positive temperature coefficient (PTC) ceramic heater in series with the vehicle HVAC system. This contains two separate ceramic heat exchangers placed downstream of the heater core within the HVAC air handling system and a separate electrical control system. Modification to the vehicle's electrical system is required in order to supply the power to the system. An example of the ceramic heater is disclosed in U.S. Pat. No. 4,459,466 issued Jul. 10, 1984 in the name of Nakagawa et al.
SUMMARY OF THE INVENTION
The invention is an auxiliary heating system for warming the passenger compartment and/or defrosting windows of an automobile having an air duct and vehicle electrical system, i.e., battery, in addition to the main heating system of a vehicle in the HVAC air handling system. The system comprises a supplementary heating means adapted to be connected in conjunction with or as the air duct. The supplementary heating means comprises electrically conductive polymer material for generating heat upon reception of electrical power from the vehicle electrical system to heat air communicated through the air duct.
Further features of the invention include terminals integral with and extending from the supplementary heating means adapted for connection to conductors of the vehicle electrical system. The supplementary heating may be comprised of molded electrically conductive plastic material.
BRIEF DESCRIPTION OF THE DRAWINGS
Advantages of the invention will be better understood by reference to the detailed drawings wherein:
FIG. 1 is a diagrammatic view of a typical heating assembly incorporation the subject invention in an automotive vehicle;
FIG. 2 is a pictorial view illustrating a first embodiment of the subject invention;
FIG. 3 is a pictorial view illustrating a second embodiment of the subject invention; and
FIG. 4 is a pictorial view illustrating a third embodiment of the subject invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An HVAC system of a vehicle 11 utilizing a supplementary heater unit 12 is generally shown at 10 in FIG. 1. The HVAC system 10 includes a radiator operatively connected to a liquid cooled engine (not shown). Duct work 16 for the system houses a conventional heater core 17 through which engine coolant circulates during vehicle operation. This duct work 16 communicates with the vehicle passenger compartment 18 for heating the compartment and/or defrosting through a vehicle air distribution duct 20. An electric fan 14 is positioned in the duct work 16 ahead of the heater core 17 to force air through the heater core and subsequently into the passenger compartment 18. A heating control circuit (not shown) is connected to the fan and conventional flow control valving in the duct work to control the temperature based on the selected position of a conventional temperature control in the passenger compartment 18. Heated air is forced into the passenger compartment 18 upon heating of the engine and flow of engine coolant through the heater core.
The supplementary heating unit 12 is adapted to be connected with, a part of, or as the air distribution duct 20 in order to provide initial and substantially immediate heat to the passenger compartment 18 upon initial operation and start-up of the vehicle 11. The supplementary heating unit 12 is made of electrically conductive polymer material, preferably a PTC (positive temperature coefficient) material, for generating heat upon reception of electrical power. The supplementary heating unit 12 comprises molded plastic or polymeric material, which may be molded as a separate insert piece 24 to the air duct 20 as illustrated in FIG. 2 by any of the plastic molding processes as commonly known in the art, i.e., injection molding, blow molding, etc. A second embodiment of the supplementary heating unit 12A may be molded as an extension 22 of the air distribution duct 20 as illustrated in FIG. 3. A third embodiment of the supplemental heating unit 12B may be molded as the entire air duct 20' as illustrated in FIG. 4. Each element 20', 22, 24 can be moldable to any shape with two open ends 40, 41, 42, 43, 44, 45 for allowing air to flow therethrough generally in the direction of the flow arrows A. A rectangular shaped element 20', 22, 24 is illustrated in the drawings as an example of one of many moldable shapes. Means 34, 36 38 are provided to increase the surface area for increasing heat transfer with the air passing therethrough, i.e., convoluted. The means 34, 36, 38 may comprise ribs extending between two sides of the element 20', 22, 24 providing a larger auxiliary heater area and resulting in increased heat transfer with the air passing therethrough.
For the insert 24 in FIG. 2, the external surface of the element 24 compliments the interior surface of the duct 20 so that the element 24 may be inserted into the duct 20 to communicate air through the element 24. For the extension element 22 in FIG. 3, it is molded as substantially the same shape as the air distribution duct 20 to further communicate air therethrough without any interruption. The internal surface of the extension element 22 is flush with the internal surface of the air distribution duct 20. For the air duct 22' in FIG. 4, it is molded as the shape required of the replaced air duct 20, but made of the electrically conductive material.
Electrical power is supplied to the molded conductive element 20', 22, 24 from the vehicle d.c. power supply 27 through wire conductor 26 to attain the proper temperature level of the air flow from the air duct 20. This connection is illustrated in FIG. 3, but applies to all elements 20', 22, 24. A prime advantage of this construction is to obtain immediate tempered air from the heater air distribution duct 20 during the initial engine/vehicle warm-up. More particularly, it does not replace the vehicle heater, but only supplements it during the approximate eight minutes of running at which time the system will cease operation and the vehicle heater system will function on its own. The fan 14 can be operated in the normal manner of the HVAC system to force air through the air duct 20. However, the air is also forced through the conductive element 20', 22, 24 thereby heating same during operation thereof. The combination of air duct 20 and conductive elements 20', 22, 24 communicates air from the heating chamber to the passenger compartment while heating same.
The assembly 10 includes control means 28 as best seen in FIG. 3 for terminating operation of the supplementary heating means 12 upon warming-up of the vehicle heater. The control means 28 may be comprised of a manual switch operated by the vehicle operator to turn on and off the supplementary heating unit 12, a discrete timing element which disconnects the supplementary heating unit from electrical power after a predetermined time upon starting of the vehicle and turning on of the main heater, i.e., eight minutes, or may include an automatic temperature control which disconnects power from the battery 27 upon temperature of the engine reaching a predetermined temperature.
The supplementary heating unit 12 includes molded terminals 30 (FIG. 3) integral with and extending therefrom adapted for connection with a connector 32 for connection with the vehicle electrical system 27. The electrical terminals 30 may be molded from the same material and in the same mold so that they are an integral part thereof. The location of the terminals 30 depends on whether concentration of the power in a certain area is desirable.
An auxiliary protection device may be required depending upon the material chosen. Some conductive polymeric materials provide their own innate protection. The polymer PTC material protects the heater system such that as the temperature reaches a certain point, the resistance raises which limits the current and therefore the power. The power and heating in the supplementary heating means 12 reaches an equilibrium which maintains the power level. As the material approaches its deformation temperature, the electrical circuit is broken.
Several electrically conductive polymer materials may be utilized having the requisite conductive plastic properties. One such material may be of the type of a PTC material which is a stainless steel filled with polycarbonate. The stainless steel fibers do not effect the base material's mechanical properties. Properties of this material include a volume resistivity in ohm-cm at 0 power to be 10 to the 0 power, deflection temperature at 66 psig is 295° F., water absorption in 24 hours is 0.12% and linear mold shrinkage of one eighth inch is 0.3%. Another material which maybe used is an aluminum flake filled ABS flame retardant.
The advantages to using an electrically conductive plastic material over ceramics is that plastics are much lighter than the equivalent options of metals and ceramics decreasing the weight requirements. Inserts may be placed in any air outlet location within the vehicle that would be effective. The material may be molded as either the original equipment duct or as an insert to the duct and molded into virtually any shape. These materials do not act as a heat sink and therefore do not retain heat and do not interfere with control head temperature linearity.
The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than limitation.
Obviously, many 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 supplementary passenger compartment heating assembly for use in conjunction with an automobile HVAC system having a forced air duct opening to the compartment includes a generally rectangular cross section air distribution duct molded integrally with the forced air duct from a heat conductive PTC polymer material. The air distribution duct has a pair of sides separated by a plurality of ribs extending therebetween so as to provide increased heat transfer area to the air forced therethrough. | 5 |
This is a division, of application Ser. No. 791,162, filed Apr. 26, 1977.
FIELD OF THE INVENTION
This invention relates to heterogeneous elastomeric blends having improved rheological properties of a major portion of a neutralized sulfonated elastomeric polymer with a minor portion of a polystyrene thermoplastic resin or a neutralized sulfonated polystyrene resin and mixtures thereof. Both the sulfonated elastomeric polymer and the sulfonated thermoplastic resin have about 0.2 to about 10.0 mole percent of SO 3 H groups, at least 90% of which are neutralized with an organic amine.
BACKGROUND OF THE PRIOR ART
U.S. Pat. No. 3,642,728, herein incorporated by reference, teaches a new class of sulfonated polymers which are derived from polymers containing olefinic unsaturation, especially elastomeric polymers, e.g. butyl and ethylenepropylene terpolymers. These materials may be neutralized with organic amines or basic materials selected from Groups I, II, III, IV, V, VI-B, VII-B and VIII and mixtures thereof of the Periodic Table of Elements. These materials, especially the butyl and the ethylene-propylene terpolymer (EPDM) derivatives, may broadly be classified as thermoelastomers, that is these materials may be processed at high temperatures by use of shear force in the presence of selected polar additives and yet at the temperature of use, e.g. room temperature, the materials, through the association of the sulfonate group behave as cross-linked elastomers. Thus, these materials represent one form of reprocessable elastomers, which are very desirable in industry.
However, although these materials are commercially useful, the melt viscosity even at very high temperature tends to be sufficiently high as to preclude the use of conventional plastic fabrication techniques. Thus, the very purpose for which these compounds are derived is not adequately fulfilled. In this invention, it has unexpectedly been discovered that decreased melt viscosity may be obtained by combining these polymers with a minor portion of a polystyrene thermoplastic resin or a sulfonated polystyrene in a heterogeneous polymer blend. Further, it has been unexpectedly discovered that the tensile properties of these blends, as measured at room temperature, can be substantially improved as compared to the sulfonated elastomers alone.
The sulfonated elastomers described in U.S. Pat. No. 3,647,728, herein incorporated by reference, when used as gums possess a relatively low level of rigidity or stiffness which yields rather limp materials incapable of supporting themselves when prepared in thin sections. This is a major limitation, if one desires to prepare dimensionally stable parts, e.g. automotive or appliance applications. It is known in the art that stiffness of elastomers may be increased by the combination of carbon black or inorganic material such as clays, calcium carbonate or silicates, etc. However, these materials, while increasing the hardness, further deteriorate the melt viscosity of the above-described ionic elastomers. Thus, systems which at best have borderline processability even at very low metal sulfonate levels further deteriorate in their flow behavior and thus cannot be processed at all. It has unexpectedly been discovered that in the compositions of the instant invention, wherein minor amounts of the unsulfonated or sulfonated polystyrene are combined with the sulfonated elastomers described above, result in increased tensile modulus at room temperature.
Thus, this invention teaches compositions of matter which represent significant improvement over the prior art in that low melt viscosity is obtained at no loss in tensile properties.
The present application is related to two other filed applications Ser. Nos. 514,502, now U.S. Pat. No. 3,905,586 and 514,512, now U.S. Pat. No. 3,923,370, herein incorporated by reference. These two applications, which have issued, are related to elastomeric blends of a crystalline polyolefinic resin and a neutralized sulfonated elastomeric blends. These blends are of a homogeneous nature, wherein the crystalline polyolefinic resin appears completely soluble in the sulfonated elastomeric polymer at elevated temperatures. The melt rheology and tensile properties of these homogeneous blends are improved as compared to the unmodified sulfonated elastomeric polymer due to the plasticization of the polymeric backbone of the elastomeric polymer. However, the blending of an inorganic filler with neutralized sulfonated elastomeric polymer creates a heterogeneous blend, wherein the rheological and physical properties are adversely affected due to incomplete interfacial bonding between the inorganic particles and the elastomeric matrix. Blends of a neutralized sulfonated elastomeric polymer and a polystyrene thermoplastic resin or a sulfonated polystyrene thermoplastic resin, wherein the thermoplastic resin is at a concentration level in excess of 20 parts per hundred by weight based on 100 parts of the neutralized sulfonated elastomeric polymer, exhibit a general deterioration in physical properties due to the manifestation of gross incompatibility. Surprisingly, it has been found that the incorporation of the polystyrene or sulfonated polystyrene at a concentration level of below about 20 parts per hundred by weight results in compositions exhibiting both improved physical and rheological properties.
SUMMARY OF THE INVENTION
It has been unexpectedly discovered that novel elastomeric heterogeneous blend compositions comprising a major portion of a sulfonated elastomeric polymer having at least 90% of the SO 3 H groups combined with an organic amine and a minor portion of a polystyrene thermoplastic resin or a neutralized sulfonated polystyrene and mixtures thereof show unexpectedly improved melt viscosity properties and improved room temperature physical properties (as compared to the sulfonated elastomer) itself. More particularly, the sulfonated elastomer is derived from an EPDM terpolymer (i.e., a terpolymer of ethylene, propylene, and a small amount, e.g., <10 mole % of a diene monomer).
Accordingly, it is an object of my present invention to provide elastomeric heterogeneous blend compositions of a neutralized sulfonated elastomeric polymer and a polystyrene thermoplastic resin or a sulfonated polystyrene, wherein these heterogeneous blend compositions have both improved physical and rheological properties as compared to the unmodified neutralized sulfonated elastomeric polymer.
A further object of my present invention is to provide a unique and novel process for the formation of these elastomeric heterogeneous blend compositions having improved physical and rheological properties.
GENERAL DESCRIPTION OF THE INVENTION
This present invention relates to unique and novel heterogeneous blend compositions of a neutralized sulfonated elastomeric polymer and a polystyrene thermoplastic resin or a sulfonated polystyrene, wherein the polystyrene is microdispersed as discrete particles in the neutralized sulfonated elastomeric polymer matrix. These heterogeneous blend compositions exhibit improved physical and rheological properties thereby permitting these heterogeneous blend compositions to be processed by conventional plastic fabricating techniques such as injection molding or extrusion.
Various chemical additives can be incorporated into the heterogeneous blend compositions for modification of a particular physical property.
The EPDM terpolymers are low unsaturated polymers having about 0.1 to about 10 mole % olefinic unsaturation defined according to the definition as found in ASTM-D-1418-64 and is intended to mean terpolymers containing ethylene and propylene in the backbone and a diene in the side chain. Illustrative methods for producing these terpolymers are found in U.S. Pat. No. 3,280,082, British Pat. No. 1,030,289 are French Pat. No. 1,386,600, which are incorporated herein by reference. The preferred polymers contain about 40 to about 80 wt. % ethylene and about 1 to about 10 wt. % of a diene monomer, the balance of the polymer being propylene. Preferably the polymer contains about 50 to about 60 wt. % ethylene, e.g. 50 wt. % and about 2.6 to about 9.0 wt. % diene monomer, e.g. 5.0 wt. %. The diene monomer is preferably a nonconjugated diene.
Illustrative of these nonconjugated diene monomers which may be used in the terpolymer (EPDM) are 1,4 hexadiene, dicyclopentadiene, ethylidene norbornene, methylene norbornene, propenyl norbornene, and methyl tetrahydroindene. The EPDM terpolymer has a number average molecular weight of about 10,000 to about 200,000, more preferably of about 15,000 to about 100,000, most preferably of about 20,000 to about 60,000. The Mooney viscosity of the EPDM terpolymer at (1+8) min. at 212° F. is about 5 to about 90, more preferably about 10 to about 50, most preferably about 15 to about 25. The Mv of the EPDM terpolymer is preferably below about 350,000 and more preferably below about 300,000. The Mw of the EPDM terpolymer is preferably below about 500,000 and more preferably below about 350,000.
A typical EPDM terpolymer is Vistalon 3708 (Exxon Chemical Co.). Vistalon 3708 is a terpolymer having a Mooney viscosity at (1+8) min. at 212° F. of about 45-55 and having about 64 wt. % ethylene, about 3.3 wt. % of 5-ethylidene-2-norbornene, and having about 53 wt. % of ethylene, about 3.5 wt. % of 1,4 hexadiene, and about 43.5 wt. % of propylene.
The polystyrene thermoplastic resins of the present invention are selected from the group consisting essentially of polystyrene, poly-t-butyl-styrene, polychlorostyrene, polyalpha methyl styrene or co- or terpolymers of the aforementioned with acrylonitrile or vinyl toluene.
The polystyrene thermoplastics suitable for use in the practice of the invention have a glass transition temperature from about 90° C. to about 150° C., more preferably about 90° C. to about 140° C. and most preferably about 90° C. to about 120° C. These polystyrene resins have a weight average molecular weight of about 5,000 to about 500,000, more preferably about 20,000 to about 350,000 and most preferably about 90,000 to about 300,000. These base polystyrene thermoplastic resins can be prepared directly by any of the known polymerization processes. The term "thermoplastic" is used in its conventional sense to mean a substantially rigid (flexus modulus>10,000 psi) material capable of retaining the ability to flow at elevated temperatures for relatively long times.
The preferred polystyrene thermoplastic resin is a homopolymer of styrene having a number average molecular weight of about 180,000, and an intrinsic viscosity in toluene of about 0.8. These polymers are widely available commercially in large volume. A suitable material is Dow Polystyrene 666 which affords a suitable molecular weight.
In carrying out the invention, the EPDM terpolymer or the polystyrene thermoplastic resin is dissolved in a nonreactive solvent such as chlorinated aromatic hydrocarbon, a chlorinated aliphatic hydrocarbon, an aromatic hydrocarbon, of an aliphatic hydrocarbon such as chlorobenzene, benzene, toluene, xylene, cyclohexane, pentane, hexane, or heptane. The preferred solvents is carbon tetrachloride for both the EPDM terpolymer and the polystyrene thermoplastic resin. A sulfonating agent is added to the solution of the EPDM terpolymer and nonreactive solvent at a temperature of about -100° C. to about 100° for a period of time of about 5 to about 60 minutes, more preferably at room temperature for 45 minutes, and most preferably at room temperature for 30 minutes. Typical sulfonating agents are described in U.S. Pat. Nos. 3,642,728 and 3,836,511, incorporated herein by reference. These sulfonating agents are selected from an acyl sulfate, a mixture of sulfuric acid and an acid anhydride of a complex of a sulfur trioxide donor and a Lewis base containing oxygen, nitrogen, or phosphorous. Typical sulfur trioxide donors are SO 3 , chlorosulfonic acid, fluorosulfonic acid, sulfuric acid, oleum, etc. Typical Lewis bases are: dioxane, tetrahydrofuran, phosphorous acid, phosphonic acid, triethylphosphate, trimethylamine, or piperidine. The most preferred sulfonation agent for the polystyrene thermoplastic is an acyl sulfate selected from the group consisting essentially of benzoyl, acetyl, propionyl or butyryl acetate. The acyl sulfate can be formed in situ in the reaction medium or pregenerated before its addition to the reaction medium. A preferred acyl sulfate is acetyl sulfate. The most preferred sulfonation agent for the EPDM terpolymer is a complex of sulfur trioxide and dioxane. It should be pointed out that neither the sulfonating agent nor the manner of sulfonation is critical, provided that the sulfonating method does not degrade the polymeric backbone. The reaction is quenched with an aliphatic alcohol being selected from methanol, ethanol, n-propanol or isopropanol, with an aromatic phenol, or with water. The acid form of the sulfonated EPDM terpolymer a polystyrene thermoplastic resin has about 10 to about 100 meq. of SO 3 H groups per 100 grams of polymer, more preferably about 15 to about 40; and most preferably about 20 to about 35. The mole percent of SO 3 H groups is about 0.2 to about 20, more preferably about 0.2 to about 10.0. The meq. of SO 3 H/100 grams of polymer was determined by both titration of the polymeric sulfonic acid and Dietert Sulfur analysis. In the titration of the sulfonic acid the polymer was dissolved in a solvent consisting of 95 parts of toluene and 5 parts of methanol at a concentration level of 50 grams per liter of solvent. The acid form is titrated with ethanolic sodium hydroxide to an Alizarin Thymolphthalein endpoint.
The solution of the acid form of the sulfonated EPDM terpolymer and the sulfonated polystyrene thermoplastic resin are mixed together and neutralized with a neutralizing agent. Neutralization of the acid forms of the sulfonated EPDM terpolymer and the sulfonated polystyrene thermoplastic resin is done by the addition of an organic amine to form an amine salt.
The organic amines used to form the ionic bonds can be primary, secondary, or tertiary amines, wherein the organic radicals are C 1 to C 30 alkyl, phenyl, aralkyl or alkaryl. More preferably, the organic radical is a phenyl, C 1 to C 10 alkyl, C 7 to C 10 alkylaryl or C 7 to C 10 aralkyl. Illustrative of such amines are anhydrous piperazine, triethylamine, tri-n-propylamine and tetraethylene-pentamine, piperazine and tri-n-propylamine.
Guanidines are preferred neutralizing agents for the sulfonic acid groups to produce ionic sites. The preferred guanidines are guanidine or substituted guanidines, wherein the substituent organic radicals are C 1 to C 30 alkyl, phenyl, aralkyl, or alkaryl. Illustrative of such guanidines are tetra-methyl guanidine, di-phenyl guanidine and di-ortho-tolyl guanidine.
The preferred neutralizing agent for the acid forms of the sulfonated EPDM terpolymer and sulfonated polystyrene thermoplastic resin is di-ortho-tolyl guanidine (DOTG). Sufficient meq. of the metal salt of the carboxylic acid or the organic amine or added to the solution of the acid forms of the sulfonated EPDM terpolymer and the sulfonated polystyrene thermoplastic to effect at least about 1 to about 100% neutralization of the acid groups, more preferably about 50 to about 100%, and most preferably about 90 to about 100%.
The mixture of the neutralized sulfonated EPDM terpolymer and the neutralized sulfonated polystyrene thermoplastic resin is isolated from solution by steam stripping to give a heterogeneous blend of the neutralized sulfonated polystyrene microdispersed in the neutralized sulfonated elastomeric polymer.
Alternatively, a polystyrene dissolved in the carbon tetrachloride resin can be added to the solution of the acid form of the sulfonated elastomeric polymer. The DOTG is added to the solution to neutralize the acid form of sulfonated elastomeric polymer. The mixture of the polystyrene thermoplastic resin and the neutralized sulfonated elastomeric polymer are isolated from solution by steam stripping to give a heterogeneous blend of the polystyrene thermoplastic resin microdispersed in the neutralized sulfonated elastomeric polymer.
In order to maximize the compatability of the polystyrene or sulfonated polystyrene into the neutralized sulfonated elastomeric polymer, it is necessary to employ a solution process. Intensive mixing process such as a Banbury extruder or a two-roll mill results in compositions, wherein the physical and rheological properties have not been maximized.
The polystyrene thermoplastic resin or the sulfonated polystyrene is a minor proportion of the heterogeneous blend at a concentration level of about 1 to about 20 parts per hundred based on 100 parts of the neutralized sulfonated elastomeric polymer, more preferably about 2 to about 15; and most preferably about 3 to about 10.
Various chemical additives can be incorporated in the blend such as fillers and oils. These chemical additives are incorporated into the heterogeneous elastomeric blend by a conventional dry blend two-roll mill technique, or by a conventional intensive mixing process such as a high steam batch Banbury or a continuous twin screw extruder. The concentration level of these additives is from about 25 to about 300 parts per hundred based on 100 parts of the neutralized sulfonated elastomeric polymer, more preferably about 30 to about 250; and most preferably about 50 to about 200.
The fillers employed in the present invention are selected from carbon blacks, talcs, ground calcium carbonate, water precipitated calcium carbonate, or delaminated, calcined or hydrated clays and mixtures thereof. Examples of carbon black are oxides, acetylinics, lamp, furnace or channel blacks. Typically these fillers have a particle size of about 0.03 to about 15 microns, more preferably about 0.5 to about 10, and most preferably about 2 to about 10. The oil absorption of the filler as measured by grams of oil absorbed by 100 grams of filler is about 10 to about 70, more preferably about 10 to about 50 and most preferably about 10 to about 30. Typical fillers employed in this invention are illustrated in Table 1.
The oils employed in the present invention are non-polar backbone process oils having less than about 3.5 wt. % polar type compounds as measured by molecular clay gel analysis. These oils are selected from paraffinics ASTM Type 104B as defined in ASTM-D-2226-70, aromatic ASTM Type 102 or naphthenics ASTM 104A, wherein the oil has a flash point by the Cleveland open cup of at least 350° F.; a pour point of less than 40° F., a viscosity of about 70 to about 3000 s.s.u.'s and a number average molecular weight of about 300 to about 1000, more preferably about 400 to about 75°. The preferred oils are napthenics. Table II illustrates typical oils encompassed by the scope of this invention.
TABLE 1__________________________________________________________________________ Oil Absorption Specific Avg. Particle Filler Code # grams of oil/100 grams of filler Gravity Size Micron pH__________________________________________________________________________calcium carbonate ground 15 2.71 9.3calcium carbonateprecipitated 35 2.65 .03-.04 9.3delaminated clay 30 2.61 4.5 6.5-7.5hydrated clay 2.6 2 4.0calcined clay 50-55 2.63 1 5.0-6.0magnesium silicate (talc) 60-70 2.75 2 9.0-9.5__________________________________________________________________________
TABLE II__________________________________________________________________________ Viscosity % % %Type Oil Oil Code # ssu 100° F. Mn Polars Aromatic Saturates__________________________________________________________________________Paraffinic Sunpar 115 155 400 0.3 12.7 87.0Paraffinic Sunpar 180 750 570 0.7 17.0 82.3Paraffinic Sunpar 2280 2907 720 1.5 22.0 76.5Aromatic Flexon 340 120 -- 1.3 70.3 28.4Naphthenic Flexon 765 506 -- 0.9 20.8 78.3Naphthenic Flexon 580 1855 -- 3.3 47.0 49.7__________________________________________________________________________
Alternatively, the oils can be incorporated in the elastomeric heterogeneous blend by the addition of the oil under agitation to the solution of the mixture of the neutralized sulfonated elastomeric polymer and the polystyrene or sulfonated polystyrene prior to the steam stripping step.
Compression molded pads were made of the heterogeneous blends at 350° F. for 5 min. wherein the sample pads were 2"×2"×0.040". Micro specimens were cut out from the pads for tensile, hardness, compression set, and stress relaxation measurements.
Tensile measurements were made by an Instron Tester at the crosshead speed of 2 in./min. using micro-dumbbell specimens. Melt rheological properties were measured by an Instron Capillary Rheometer with a 0.050"D×1", L, 90° entrance angle capillary.
The application for the heterogeneous blends of this invention are diverse. The blends have excellent injection molding and extrusion properties. For example, injection molded shoe soles may be prepared from the instant blends because of their excellent abrasion resistance and flex fatigue properties which are highly desired in such application. Injection molded parts for automotive applications may be prepared from the blends of this invention, e.g., automobile sight shields, flexible bumpers, grill parts, etc. It is readily apparent to those skilled in the art that the properties, such as rigidity, can be varied widely depending on the level of the polystyrene or sulfonated polystyrene incorporated in the sulfonated elastomeric polymer, thus fabrication of rigid or semiflexible articles from the instant blends is contemplated. Articles from the blends of the instant invention may also be prepared by extrusion techniques. For example, garden hose, having outstanding strength in combination with light weight is one application. The electrical properties of these materials also allow the use of the instant blends as insulation for wire. Insulation prepared from rubber or polyethylene often requires a curing or vulcanization step to obtain optimum properties. The blends of this invention have excellent physical properties, and excellent electrical properties without the need for any curing step. The fact that chemical curing is not required permits a relatively high speed extrusion operation which are not feasible with those systems requiring a curing step.
Other fabrication processes for these materials include vacuum forming, flow molding, slit extrusion, profile extrusion and similar operations. The wide versatility, from a fabrication viewpoint, permits the use of these blends in film, containers such as bottles, oriented sheet, fibers, especially oriented monofilament, packaging, appliance housing, floor mats, carpet backing, toys, sporting goods such as swim fins, face masks, and similar applications.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and features of the invention may be understood with reference to the following detailed description of an illustrative embodiment of the invention taken together with the accompanying drawings in which:
FIG. 1 illustrates a graph of gum tensile properties at room temperature and the effect of sulfonation on an EPDM terpolymer;
FIG. 2 illustrates a graph of gum tensile properties at 200° C.;
FIG. 3 illustrates a graph of stress relaxation as a function of temperature;
FIGS. 4 and 5 illustrates a graph of the rheological properties of a sulfo-EPDM at 200° C.;
FIG. 6 illustrates a graph of the tensile properties of a sulfo-EPT (EPDM) at room temperature;
FIG. 7 illustrates a graph of the tensile properties of sulfo-EPT (EPDM) compound at room temperature;
FIG. 8 illustrates a graph of the tensile properties of a sulfo-EPT (EPDM) gum at room temperature;
FIG. 9 illustrates a graph of the tensile properties of a sulfo-EPT (EPDM) compound at room temperature;
FIG. 10 illustrates a graph of the tensile properties of the sulfo-EPT (EPDM) gum at room temperature;
FIG. 11 illustrates a graph of the tensile properties of the sulfo-EPT (EPDM) compound at room temperature;
FIG. 12 illustrates a graph of the tensile properties of the sulfo-EPT (EPDM) gum at room temperature as effected by the sulfonation level of a polystyrene; and
FIG. 13 illustrates a graph of the tensile properties of the sulfo EPT (EPDM) gum at room temperature as effected by the sulfonation level of a polystyrene.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The advantages of the unique and novel elastomeric heterogeneous blend compositions and the unique and novel process for the formation of these compositions can be more readily appreciated by reference to the following examples, tables, and figures.
EXAMPLE I
PREPARATION OF AN ACID FORM OF A SULFONATED EPDM TERPOLYMER
To a solution of 90 grams of EPDM terpolymer (Vistalon 3708-Exxon Chemical Co.) in 3 liters of carbon tetrachloride at 50° C. was added a solution of a sulfonating agent which was formed at 10° from 141 ml. of methylene chloride, 2.4 ml. of sulfur trioxide, and 5 ml. of dioxane. Sulfonation was terminated after 30 min. by quenching with methanol. The acid form of the sulfonated EPDM terpolymer had 0.8 mole percent of SO 3 H groups/100 grams of terpolymer.
EXAMPLE II
PREPARATION OF AN ACID FORM OF A SULFONATED POLYSTYRENE RESIN
To a solution 20.8 grams of a polystyrene resin having an Mw of 287×10 3 (Styron 666) in 100 ml. of carbon tetrachloride at 50° C. was added a solution of a sulfonating agent which was formed at 10° C. from 4.762 ml. of ethylene dichloride, 0.905 ml. of anhydrous acetic anhydride and 0.333 ml. of 96.5% concentrated sulfuric acid and sulfonation was terminated after 60 min. by quenching with methanol. The acid form of the sulfonated polystyrene resin had 3.0 mole percent of SO 3 H groups/grams of polystyrene resin. Sulfonated polystyrene resins having an Mw of 93×10 3 were also prepared, wherein the mole percent of SO 3 H was 3.0 or 6.0.
EXAMPLE III
PREPARATION OF ELASTOMERIC BLEND COMPOSITIONS
To the quenched solution of the sulfonated EPDM terpolymer, prepared according to Example I, was added a solution of polystyrene resin dissolved in carbon tetrachloride having an Mw of 93×10 3 or 287×10 3 . The resultant blended solution was neutralized at room temperature for 30 min. with di-ortho-tolyl guanidine (DOTG). The elastomeric blend compositions were recovered from solution by steam stripping.
Alternatively, to the quenched solution of the sulfonated EPDM terpolymer prepared according to Example I was added the solutions of Example II of the acid form of the sulfonated polystyrene resin having an Mw of 287×10 3 or 93×10 3 . The resultant blended solution was neutralized at room temperature for 30 minutes with di-ortho-tolyl guanidine. The elastomeric blend compositions were isolated from solution by steam stripping.
The elastomeric blend compositions were compounded on a hot micro-rubber mill. Sample pads of 2"×2"×0.040" were molded at 35° F. for 5 min. Micro-specimens were cut out from the pads for tensile hardness, compression set and stress relaxation measurements.
Table III illustrates the formulas for these blend compositions and their physical properties as compared to an unsulfonated EPDM 3708 terpolymer, a sulfonated EPDM 3708 terpolymer, and Kraton 101.
TABLE III__________________________________________________________________________ELASTOMERIC BLEND COMPOSITIONSwt. % ofsulfonated wt. % ofEPDM ter- sulfonatedpolymer polystyrene Compression Set Other0.8 mole % Sample wt. % of 3.0 mole % --Mw Shore A ASTM-R Elastomericof SO.sub.3 . DOTG # polystyrene of SO.sub.3 . DOTG polystyrene Hardness RT 40° C. Resin__________________________________________________________________________100 1-1 -- -- -- 73.0 43.5 76.990 1-2 10 -- 287 × 10.sup.3 74.0 48.8 10090 1-3 -- 10 287 × 10.sup.3 73.0 39.9 10080 1-4 20 -- 287 × 10.sup.3 80.0 52.2 10080 1-5 -- 20 287 × 10.sup.3 76.0 46.2 10090 1-6 10 -- 93 × 10.sup.3 76.0 43.0 77.190 1-7 -- 10 93 × 10.sup.3 80.0 39.3 77.7-- 1-8 -- -- -- 65.0 39.0 84.9-- 1-9 -- -- -- 63.0 41.0 61.0 EPDM 3708 Kraton 101__________________________________________________________________________
Sulfonation of EPDM 3708 improves the tensile properties as shown in FIG. 1 as compared to unsulfonated EPDM 3708; however, sulfonation and neutralization severely deteriorates the rheological properties of EPDM as shown in FIG. 2. The neutralized sulfonated EPDM 3708 has very poor flow stability manifested by melt fracture at a low shear rate of 15 sec -1 and about 3 times as high viscosity at 200° C. as that of unsulfonated EPDM 3708. The hardness as seen in Table I of the EPDM terpolymer increases upon sulfonation and neutralization. The addition of 10 percent of polystyrene having an Mw of 287×10 3 or sulfonated polystyrene having an Mw of 287×10 3 does not change the hardness. However, the addition of either 10% of sulfonated or unsulfonated polystyrene having an Mw of 93×10 3 increases the hardness. Increasing the wt. % of the sulfonated or unsulfonated polystyrene increases slightly the hardness. The addition of the sulfonated or unsulfonated polystyrene has little effect on the compression set, wherein the compositions with sulfonated polystyrene has somewhat lower compression set than samples from unsulfonated polystyrene.
FIG. 3 shows the effect of the sulfonated polystyrene on the equilibrium stress relaxation modulus of sulfonated EPDM 3708 as a function of temperature. Ten percent of sulfonated polystyrene has no effect on the equilibrium stress relaxation modulus of the sulfonated EPDM 3708.
FIGS. 4 and 5 show the improvements in the rheological properties of the DOTG neutralized sulfonated EPDM 3708 by the addition of the sulfonated or unsulfonated polystyrene. In both cases, the viscosity is reduced and the flow stability is improved. FIGS. 4 and 5 also show that the rheological properties are uneffected by changes in the Mw of the sulfonated or unsulfonated polystyrene.
FIGS. 6-11 show the effect on tensile properties of the addition of the sulfonated or unsulfonated polystyrene to the sulfonated EPDM 3708 matrix. The sulfonated polystyrene appears to improve the tensile properties better than does the unsulfonated polystyrene.
FIGS. 12 and 13 show the effect of the sulfonation level of the polystyrene on the tensile properties of the blended elastomeric composition. Six mole percent sulfonated polystyrene gives somewhat inferior tensile properties as compared to 3 mole percent sulfonated polystyrene at the same loading.
EXAMPLE IV
The compositions of Example III including the sulfonated EPDM 3708 were blended according to the following formula and compounded on a micro-two roll rubber mill to give extended elastomeric blend compositions.
______________________________________ wt. percent______________________________________Blend Compositions of Example III 28.57Flexon Oil 580 (Exxon Chemical Co.) 28.57HAF Carbon Black (Cabot Corp.) 42.86______________________________________
Sample pads of 2"×2"×0.040" were molded at 350° F. for five min. and micro-specimens were cut out for physical testing.
Tables III and IV clearly show that the incorporation of the filler and oil generally increases the hardness and compression set for the elastomeric blend compositions of the neutralized sulfonated EPDM 3708 and either the neutralized sulfonated or unsulfonated polystyrene.
FIGS. 7, 9 and 10 show the tensile properties for the extended elastomeric blend compositions that the tensile properties are improved by the addition of either neutralized sulfonated or unsulfonated polystyrene, wherein the neutralized sulfonated polystyrene seems to be somewhat more effective.
The elastomeric blend compositions prepared by the improved unique and novel process of this invention can be fabricated by conventional rubber fabricating techniques into a number of useful articles. For example, film, washer hose and radiator hose have been made by an extrusion process.
Since, many modifications of this invention may have been made without departing from the spirit or scope of the invention thereof, it is not intended to limit the scope or spirit to the specific examples thereof.
TABLE IV__________________________________________________________________________ELASTOMERIC BLEND COMPOSITIONSEXTENDED WITH FILLER AND OILwt. % ofsulfonated wt. % ofEPDM ter- sulfonatedpolymer polystyrene Compression Set0.8 mole % Sample wt. % of 3.0 mole % Mw Shore A ASTM-Rof SO.sub.3 . DOTG # polystyrene of SO.sub.3 . DOTG polystyrene Hardness RT 40° C.__________________________________________________________________________100 2-1 -- -- -- 81 100 10090 2-2 10 -- 287 × 10.sup.3 85 100 10090 2-3 -- 10 287 × 10.sup.3 83 80.7 10080 2-4 20 -- 287 × 10.sup.3 87 100 10080 2-5 -- 20 287 × 10.sup.3 85 100 10090 2-6 10 -- 93 × 10.sup.3 72 71.5 10090 2-7 -- 10 93 × 10.sup.3 81 87.1 96.3__________________________________________________________________________ | This invention relates to heterogeneous elastomeric blends having improved rheological properties of a major portion of a neutralized sulfonated elastomeric polymer with a minor portion of a polystyrene thermoplastic resin or a neutralized sulfonated polystyrene resin and mixtures thereof. Both the sulfonated elastomeric polymer and the sulfonated thermoplastic resin have about 0.2 to about 10.0 mole percent of SO 3 H groups, at least 90% of which are neutralized with an organic amine. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a turbofan, and more particularly, to a turbofan and a mold manufacturing the same.
[0003] 2. Background of the Related Art
[0004] Generally, a turbofan is a kind of centrifugal fan sending air forcibly by a centrifugal force of air generated from revolution of an impeller thereof. The turbofan produces massive airflow so as to be suitable for a refrigerator of heavy capacity.
[0005] [0005]FIG. 1 illustrates a layout of a turbofan according to a related art, and FIG. 2 illustrates a vertical cross-sectional view of the general turbofan in FIG. 1.
[0006] Referring to FIG. 1 and FIG. 2, a turbofan 1 according to a related art includes a hub 10 having a boss 11 at a central part so as to be coupled with a rotational shaft 40 of a driving device (not shown in the drawings), a plurality of blades 20 at a circumferential part 10 a of the hub 10 , and a shroud 30 arranged at a opposite face to the hub 10 so as to be coupled with the blades in one body wherein the blades 20 are inserted between the shroud 30 and the hub 10 .
[0007] An internal diameter increases toward the hub 10 in a direction of the rotational shaft 40 , and has a concave shape. A cross-section of each blade 20 , as shown in FIG. 1, has an airfoil figure.
[0008] The above-constructed turbofan 1 according to the related art is mainly manufacture by injection molding of synthetic resin. The blades 20 and hub 10 are formed in one body, but the shroud 30 is molded separately. Theses parts are assembled reciprocally so as to complete the turbofan 1 .
[0009] When the turbofan is manufactured by the above process, the number of molding patterns increases, whereby consumes time and expense excessively. Besides, the above process needs a step of assembling separate parts, thereby extending a manufacturing time to increase overall cost of product.
[0010] In order to overcome the above disadvantages or defects, a process of manufacturing a turbofan is lately used so as to reduce the number of molding patterns and skip an auxiliary assembling step. Namely, in the latest process, a maximum outer diameter dl of the hub 10 is reduced to a size less than a minimum inner diameter d 2 . And, longitudinal boundary surfaces (BSL) of upper and lower molding patterns are formed to have an inner diameter equal to the maximum outer diameter dl so as to assemble the hub 10 , blades 20 , and shroud 30 in one body reciprocally.
[0011] [0011]FIG. 3 illustrates longitudinal cross-sectional views of a turbofan and a molding pattern to manufacture a turbofan, and FIG. 4 illustrates a magnified cross-sectional view of the assembly of the molding pattern in FIG. 3.
[0012] Referring to FIG. 3 and FIG. 4, a molding pattern for forming a turbofan according to a related art includes a lower molding pattern part 50 arranged to be fixed to a lower part in a direction of a rotational shaft 40 and having a molding surface inside to form a partial area of a hub 10 and blades 20 and an upper molding part 60 having a molding surface inside to form the rest area of the shroud 30 and blades 20 and providing a space to form the turbofan 1 by being assembled with the lower molding part 50 .
[0013] A hub molding part 61 recessed in a direction of the rotational shaft 40 is formed at a central part of the molding surface of the upper molding pattern part 60 so as to form the hub 10 . And, a boss molding part 62 is formed at a central part of the hub molding part 61 so as to mold the boss 11 . Along a radial direction of the rotational shaft 40 , a blade molding part 63 is formed at an external side of the boss molding part 62 so as to form the blade 20 in part. Along a direction of the rotational shaft 40 , a shroud molding part 64 is formed over the blade molding part 63 so as to form an upper surface of the shroud 30 .
[0014] Meanwhile, a hub molding part 51 protrudes out of the central part of the upper surface of the lower molding pattern part 50 , and a boss molding part 52 is formed at a central part of the hub molding part 51 . Along a radial direction of the rotational shaft 40 , a blade molding part 53 is formed at an external side of the hub molding part 51 so as to mold the rest part of the blades 20 . And, a concave shroud molding part 54 is formed at an upper part of the blade molding part 53 so as to form a lower surface of the shroud 30 .
[0015] In order to manufacture the above-constructed turbofan, when the upper molding pattern part 60 is tightly coupled with the lower molding pattern part 50 , a molding space to form the turbofan constructed with the hub 10 , blades 20 , and shroud 30 , which are built in one body, is provided inside the lower and upper molding pattern parts 50 and 60 . A molten synthetic resin is then injected in the molding space for the turbofan. After the injected synthetic resin has been hardened, the upper and lower molding pattern parts 60 and 50 are separated from each other as well as the turbofan 1 is separated, the turbofan having the hub, blades 20 and shroud 30 formed in one body is manufactured.
[0016] In the turbofan according to the related art, the inner diameter of the shroud 10 increases when getting closer to the hub 10 along a direction of the rotational shaft 40 so as to guide airflow with the hub 10 . Thus, a cross-section of the shroud 10 is concave. In the molding pattern for form the shape of the shroud 30 , the longitudinal boundary surface BSL, at which the lower and upper molding pattern parts 50 and 60 meet each other, is formed along the direction of the rotational shaft 40 , and an edge 55 is formed at a contact between the longitudinal boundary surface BSL and the shroud molding part 54 of the lower molding pattern part 50 . Such a sharp edge 55 , when being contacted with the upper molding pattern part 60 , is damaged or distorted by a relatively small external force with ease. Hence, durability of the molding pattern is shortened so as to need a replacement frequently. Thus, the turbofan according to the related art increases cost of product.
SUMMARY OF THE INVENTION
[0017] Accordingly, the present invention is directed to a turbofan and mold manufacturing the same that substantially obviates one or more problems due to limitations and disadvantages of the related art.
[0018] An object of the present invention is to provide a turbofan and mold manufacturing the same enabling to increase durability of the mold for manufacturing a turbofan by improving the structure of the turbofan.
[0019] 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.
[0020] To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a turbofan according to the present invention includes a hub coupled with a rotational shaft of a driving device, a plurality of blades installed at a circumference of the hub radially, and a shroud at an opposite side to the hub so as to be coupled with a plurality of the blades wherein the blades are placed between the shroud and the hub, and wherein the hub, blades, and shroud are formed in one body and wherein the shroud comprises a first extension protruding to extend from a coupling part with a leading edge of each of the blades in an inward radial direction of the rotational shaft and a second extension extending straightly from the first extension in a direction of the rotational axis toward a side opposite to the hub.
[0021] In another aspect of the present invention, for fabricating a turbofan including a hub coupled with a rotational shaft of a driving device, a plurality of blades installed at a circumference of the hub radially, and a shroud at an opposite side to the hub so as to be coupled with a plurality of the blades wherein the blades are placed between the shroud and the hub, and wherein the hub, blades, and shroud are formed in one body and wherein the shroud comprises a first extension protruding to extend from a coupling part with a leading edge of each of the blades in an inward radial direction of the rotational shaft and a second extension extending straightly from the first extension in a direction of the rotational axis toward a side opposite to the hub, assuming that a surface where the blades are formed is an upper surface by taking the hub as a reference, a mold for fabricating the turbofan includes lower and upper mold patterns. The lower mold pattern includes a hub molding part for molding a lower surface of the hub, a blade molding part protruding upward from a circumferential end of the hub molding part in a direction of the rotational shaft so as to mold a portion of each of the blades, and a shroud molding part for molding a lower surface of the shroud having the first extension at an upper area of the blade molding part. And, the upper molding pattern includes a hub molding part detachable from the upper mold pattern for molding an upper surface of the hub, a blade molding part having a boundary surface forming a boundary with an inner side of the blade molding part of the upper mold pattern for molding a rest portion of each of the blades, and a shroud molding part for molding an upper surface of the shroud having the second extension.
[0022] 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
[0023] 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.
[0024] In the drawings:
[0025] [0025]FIG. 1 illustrates a layout of a turbofan according to a related art;
[0026] [0026]FIG. 2 illustrates a vertical cross-sectional view of the general turbofan in FIG. 1;
[0027] [0027]FIG. 3 illustrates longitudinal cross-sectional views of a turbofan and a molding pattern to manufacture the turbofan;
[0028] [0028]FIG. 4 illustrates a magnified cross-sectional view of the assembly of the molding pattern in FIG. 3;
[0029] [0029]FIG. 5 illustrates a bird's-eye view of a turbofan according to a first embodiment of the present invention;
[0030] [0030]FIG. 6 illustrates a longitudinal cross-sectional view of the turbofan in FIG. 5;
[0031] [0031]FIG. 7 illustrates a longitudinal cross-sectional view of a turbofan according to a second embodiment of the present invention;
[0032] [0032]FIG. 8 illustrates longitudinal cross-sectional views of a turbofan and a mold to manufacture the turbofan according to a first embodiment of the present invention;
[0033] [0033]FIG. 9 illustrates a magnified cross-sectional view of the assembly of mold patterns in FIG. 8;
[0034] [0034]FIG. 10 illustrates longitudinal cross-sectional views of a turbofan and a mold to manufacture the turbofan according to a second embodiment of the present invention; and
[0035] [0035]FIG. 11 illustrates a magnified cross-sectional view of the assembly of mold patterns in FIG. 10.
DETAILED DESCRIPTION OF THE INVENTION
[0036] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
[0037] [0037]FIG. 5 illustrates a bird's-eye view of a turbofan according to a first embodiment of the present invention, and FIG. 6 illustrates a longitudinal cross-sectional view of the turbofan in FIG. 5.
[0038] Referring to FIG. 5 and FIG. 6, a turbofan according to a first embodiment of the present invention includes a hub 110 having a boss 111 at a central part so as to receive to be coupled with a rotational shaft 140 of a driving device (not shown in the drawings), a shroud 130 guiding a flow of air with the hub 110 , and a plurality of blades 120 arranged radially at a circumferential part of the hub 110 centering around the rotational shaft 140 so as to be coupled with the shroud 130 . And, the hub 110 , shroud 130 , and blades 120 are built in one body.
[0039] The hub 110 includes a boss 111 protruding along a direction of the rotational shaft 140 so as to receive to be coupled with the rotational shaft 140 of the driving device (not shown in the drawings) and a circumferential part 112 extending along a radial direction of the rotational shaft 140 so as to guide the flow of air inflow with the shroud 130 .
[0040] Each of the blades 120 is arranged on the circumferential part 112 of the hub 110 , and a cross-section of each blade 120 has am airfoil figure.
[0041] A cross-sectional figure of the shroud 130 , as shown in FIG. 6, includes a first extension 132 extending in a internal radial direction of the rotational shaft from a part connected to an inner side 121 of the blade 120 , a second extension 131 of which inner diameter D 1 is equal to or longer than a maximum outer diameter D 2 of the hub 110 and of which inner diameter surface protrudes from the first extension 132 in parallel with the rotational shaft, and a shroud body 133 of which inner diameter increases gradually toward the hub 110 along the direction of the rotational shaft 140 from the first extension 132 .
[0042] The second extension 131 , as shown in FIG. 6, extends from an inner end 132 a of the first extension 132 so as to form an ‘L’ figure with the first extension 132 .
[0043] And, the part at which the first extension 132 , as shown in the magnified portion in FIG. 6, is connected to the shroud body 133 is preferably curved concavely when being looked at from the blade 120 so as to smooth the inflow of air.
[0044] Besides, the second extension 131 of the shroud 130 may extend from an outer end of the second extension 132 .
[0045] [0045]FIG. 7 illustrates a longitudinal cross-sectional view of a turbofan according to a second embodiment of the present invention.
[0046] Referring to FIG. 7, a second extension 231 of a shroud 230 extends from an outer end 232 b of a first extension 232 so as to form an ‘L’ figure, and is connected to the shroud body 233 by the same continuous surface.
[0047] Moreover, the part at which the first extension 232 , as shown in the magnified portion in FIG. 7, is connected to the shroud body 233 is preferably curved concavely when being looked at from the blade 220 so as to smooth the inflow of air.
[0048] Meanwhile, the turbofan according to the first or second embodiment of the present invention may be manufactured by injection molding. A mold is required for molding injection of the turbofan, which is explained in the following description in detail.
[0049] [0049]FIG. 8 illustrates longitudinal cross-sectional views of a turbofan and a mold to manufacture the turbofan according to a first embodiment of the present invention, and FIG. 9 illustrates a magnified cross-sectional view of the assembly of mold patterns in FIG. 8.
[0050] [0050]FIG. 10 illustrates longitudinal cross-sectional views of a turbofan and a mold to manufacture the turbofan according to a second embodiment of the present invention, and FIG. 11 illustrates a magnified cross-sectional view of the assembly of mold patterns in FIG. 10.
[0051] Referring to FIGS. 8 to FIGS. 11, a mold to manufacture the turbofan according to the first or second embodiment of the present invention, when being divided into an upper part having the blades 120 and a lower part by taking the hub 110 as a reference, includes an upper mold pattern 160 or 260 and a lower mold pattern 150 or 250 which form a molding space for manufacturing the turbofan by assembly.
[0052] One of the upper mold pattern 160 or 260 and the lower mold pattern 150 or 250 is arranged to be fixed to something, while the other is detachable by assembly/disassembly in a direction of the rotational shaft 140 .
[0053] An upper surface of the lower mold pattern 150 or 250 has a hub molding part 151 , a blade molding part 153 , and a shroud molding part 154 or 254 so as to mold the hub 110 , blades 120 , and shroud 130 or 230 with the upper mold pattern 160 or 260 , respectively.
[0054] A central part of the hub molding part 151 protrudes in the direction of the rotational shaft 140 , and a boss molding part 152 protrudes from an upper area of the hub molding part 151 so as to mold an inner diameter surface of the boss 111 .
[0055] The blade molding part 153 forms a portion of each of the blades 120 . The blade molding part 153 protrudes upward in a direction of the rotational shaft 140 from one end 151 a of the hub molding part 151 along a radial direction of the rotational shaft 140 , and has a longitudinal boundary surface BSL having an inner diameter equal to the maximum outer diameter D 2 of the hub 110 .
[0056] At an upper part of the blade molding part 153 , formed are a first extension molding part 155 or 255 and a shroud body molding part 154 or 254 extending in a radial direction of the rotational shaft 140 so as to mold lower surfaces of the first extension 132 or 232 and shroud body 133 or 233 .
[0057] Specifically, the lower mold pattern 150 or 250 , as shown in FIG. 9 or FIG. 11, has a corresponding convex part so as to make the concavely-curved surface of the connecting portion between the first extension 132 or 232 and the shroud body 133 or 233 .
[0058] A lower surface of the upper mold pattern 160 or 260 has a hub molding part 161 , a blade molding part 163 , and a shroud molding part 164 or 264 so as to mold the hub 110 , blades 120 , and shroud 130 or 230 with the upper mold pattern 160 or 260 , respectively.
[0059] The hub molding part 161 is recessed upward from a central part of the lower surface of the upper mold pattern 160 or 260 so as to mold the upper surface of the hub 110 , and a boss molding part 162 is formed at a central area of the hub molding part 161 .
[0060] At an end 161 a of the hub molding part 16 , a longitudinal boundary surface BSL having an outer diameter similar to the maximum outer diameter D 2 of the hub 110 is formed so as to make a pair with the longitudinal boundary surface BSL of the blade molding part 153 in the lower mold pattern 150 or 250 . And, a blade molding part 163 is formed inside the longitudinal boundary surface BSL so as to mold the rest of the blades 120 .
[0061] At an upper part of the blade molding part 163 in a direction of the rotational shaft 140 , as shown in FIG. 10 or FIG. 11, a shroud molding part 164 or 264 is formed to correspond to the second extension 132 or 232 in the turbofan according to the first or second embodiment of the present invention so as to mold the second extension 131 or 231 , an upper surface of the first extension 132 or 232 , and an upper surface of the shroud body 133 or 233 .
[0062] Namely, the mold for the turbofan according to the first embodiment of the present invention, as shown in FIG. 9, forms a molding space for the second extension 131 to extend to the longitudinal boundary surface BSL of the upper mold pattern 160 . Yet, the mold for the turbofan according to the second embodiment of the present invention, as shown in FIG. 11, forms a molding space for the second extension 231 outside the longitudinal boundary surface BSL of the upper mold pattern 260 so as to continue from the upper surface with the shroud body 233 .
[0063] The above-constructed turbofan according to the first or second embodiment of the present invention is manufactured using the above mold(s) by the following process.
[0064] First, the lower mold pattern 150 or 250 and the upper mold pattern 160 or 260 are assembled together. A molten synthetic resin is then injected in the molding space provided by the assembly of the lower mold pattern 150 or 250 and the upper mold pattern 160 or 260 . After the injected synthetic resin has been hardened, the upper and lower mold patterns 150 / 160 or 250 / 260 are separated from each other. The molded turbofan is then separated from the lower mold pattern 150 or 250 .
[0065] As mentioned in the above description, the present invention improves the structure of the coupling part at which the shroud and blade insides are coupled so as to prevent the sharp edge from occurring in the mold for the turbofan fabrication.
[0066] Accordingly, the present invention elongates durability of the mold, thereby enabling to reduce cost of product.
[0067] The forgoing embodiments are merely exemplary and are not to be construed as limiting the present invention. The present teachings can be readily applied to other types of apparatuses. The description of the present invention is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. | Disclosed is a turbofan which includes a hub coupled with a rotational shaft of a driving device, a plurality of blades installed at a circumference of the hub radially, and a shroud at an opposite side to the hub so as to be coupled with a plurality of the blades wherein the blades are placed between the shroud and the hub, and wherein the hub, blades, and shroud are formed in one body and wherein the shroud comprises a first extension protruding to extend from a coupling part with a leading edge of each of the blades in an inward radial direction of the rotational shaft and a second extension extending straightly from the first extension in a direction of the rotational axis toward a side opposite to the hub. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to U.S. provisional Application Ser. No. 60/874,329 entitled Carburetor Spacer, filed Dec. 12, 2006
BACKGROUND OF THE INVENTION
[0002] a) Field of the Invention
[0003] This invention relates in general to the field of improved internal combustion engine
[0000] performance, and in particular to methods and apparatus to assist in stabilizing the flow
of flow of fuel mixture into the intake manifold of a carbureted internal combustion engine by providing and improved carburetor spacer
[0004] b) Description of the Prior Art
[0005] It is advantageous for carbureted internal combustion engines, especially engines used in performance automobiles or racing automobiles, to increase performance by developing maximum power and torque throughout the revolutions per minute (RPM) range of the engine. Such performance is usually manifested in engine throttle response and acceleration and of course top speed.
[0006] In a carbureted engine, the carburetor serves to determine the amount of fuel and oxidizer to be provided to the cylinders for burning and production of power. Thus air, an oxidizer, or another oxidizer, such as nitrous oxide, and fuel, usually gasoline, are input to a carburetor which meters both the air and oxidizer to provide a predetermined ratio of fuel and oxidizer. The carburetor also atomizes or vaporizes the fuel and mixes it with the oxidizer such that optimum burning of the fuel occurs during the power stroke of the pistons. Thus, the carburetor sets the stage for the ultimate performance of the engine. However, the output of a carburetor must be delivered in equal parts to each of the cylinders of an engine in order to continue the performance chain. An intake manifold serves this function. Many improvements have been made to intake manifolds in the nature of maintaining the previously supplied optimal mixture of the atomized fuel-oxidizer by not allowing the fuel to revert back to its liquid state and deposited out of the mixture onto one or more surfaces of the intake manifold, and to minimize pressure drop losses within the intake manifold that can inhibit the maximum flow of the fuel-oxidizer mixture.
[0007] In the relatively recent past, the performance of carbureted engines have been improved by the advent of a spacer located between the outlet of the carburetor and the inlet of the intake manifold. The spacer being exactly as it is stated, a device that adds space between the carburetor and the intake manifold. As would be expected, the spacer has been improved over the years and present day spacers significantly add to the power and torque produced by performance engines.
[0008] Present day spacers take a number of different forms. They are of different lengths, different internal sizes, have one or more flow passages, are made from different material, are manufactured by different methods such as casting, CNC machining, and the internal passages have taken on different shapes—all or any one of them to improve velocity of the fuel-oxidizer, the atomization and vaporization of the fuel, the oxygenation of the fuel and the mixing of the fuel and oxidizer. Still another improvement has been to provide means within the spacer to input an additional oxidizer and fuel. My previous U.S. Pat. No. 6,269,805, issued Aug. 7, 2001. is directed to this latter improvement.
[0009] Unfortunately, there are factors that occur during the operation and running of an internal combustion engine that tend to upset even a very carefully optimized and distributed fuel mixture. For example, the engine itself creates vibrations and resonances during its operation which can result in disturbing the atomization, vaporization, oxygenation, and distribution of the fuel mixture and therefore disadvantageously affect the output of the engine. Additional vibrations and resonances can be induced into the fuel mixture delivery system due to the engine being connected to its supporting structure. For example, if the engine is bolted directly to its supporting structure with no rubber or isolation dampening medium placed between the engine and its mounting structure, which direct bolting is often used in race cars. the probably of induced vibrations is increased. Even with the use of an isolation medium between the engine and its supporting structure, vibrations can be induced. Likewise, if the engine is used in an automobile, performance or otherwise, the road conditions can have an effect on the induced vibrations. There are probably other factors that cause and or aggravate the unwanted vibrations. As noted, the vibrations are one factor that can reduce the optimum performance of an internal combustion engine by disturbing the preferred or optimal atomization and distribution of the fuel mixture.
[0010] Accordingly, it is a primary object of the present invention to minimize the effect of the ever present resonances and vibrations on the atomization, vaporization, mixing, and distribution of the fuel mixture being delivered to the cylinders of an internal combustion engine. The present invention accomplishes this objective in a proven manner.
SUMMARY OF THE INVENTION
[0011] The present invention comprises a three piece spacer. One part being a male member, an other being a female member, and an elastomeric member. The male portion fits within the female portion leaving a space therebetween. The elastomeric member fits within the space between the male and female members and between an end of he female member and an underside of a flange of the male member. The three members comprising the spacer are held together by friction. The elastomeric member serves as a vibration and resonance isolator between the male and female portions by allowing relative movement between the male and female members. By locating the spacer between a carburetor and an intake manifold of an internal combustion engine, vibrations and the resonances thereof, of the engine are precluded from being induced in the intake manifold attached thereto. This in turn prevents the vaporized fuel in the fuel-oxidizer mixture from reforming as a liquid which would adversely affect complete combustion of the fuel when caused to burn in the engine's cylinders.
[0012] The preferred details of the disclosed embodiments and the advantages thereof are further described below and in conjunction with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Various other objects, advantages, and features of the invention will become apparent to those skilled in the art from the following discussion taken in conjunction with the following drawings, in which:
[0014] FIG. 1 is a composite, isometric rendering of the various components of the inventive spacer illustrating the manner in which the components are assembled;
[0015] FIG. 2 is a cross sectional view of an assembled spacer illustrating a preferred embodiment of the elastomeric isolator and its position within the spacer;
[0016] FIG. 3 is cross sectional view of another embodiment of the elastomeric isolator; and
[0017] FIG. 4 is cross sectional view of another embodiment of the elastomeric isolator;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting; but rather, to provide an understandable description of the invention.
[0019] Reference is now made to the drawings accompanying this application. FIG. 1 is an isometric rendering of the various components which are shown in an expanded view for purposes of clarity.
[0020] The inventive spacer comprises three major components, a male member 11 , a female member 12 and an isolator member 13 . The male member 11 is configured to fit within the female member 13 with a space therebetween. The space is provided to fit therein the isolator 13 . Thus, the isolator is interposed between the female member and the male member. The fitup between the three parts is a close fit such that essentially no space or gap exists between the parts when they are assembled and the members are held together bay friction.
[0021] FIG. 2 is a cross sectional view taken along an axial center line of the assembled spacer 10 . The male member 11 includes a flange 14 at one end thereof. A hollow portion 15 depends from the flange 14 . Both the flange 14 and the depending portion 15 include an opening 16 therethrough. The opening 16 provides the flow channel for the fuel-oxidizer mixture flowing from a carburetor to an intake manifold of an internal combustion engine to which the spacer 10 is adapted to be assembled therebetween. The carburetor being sealingly attached to the upper end of flange 14 . The openings 21 in flange 14 provide for this attachment, such as by bolts and nuts. The seal between the carburetor and the flange can be effectuated by a gasket or other well known method of sealing a metal to metal joint.
[0022] The female member 12 includes a flange 17 and an attached extending portion 18 . The extending portion 18 of female member 12 extends upward from flange 17 . A through opening 19 is provided in flange 17 and extending portion 18 . Opening 19 is larger than the outside dimension of the depending portion 15 of the male member 11 . Thus, a space exists between the inside of the extending portion 18 and the outside of depending portion 15 . Additionally, the length of depending portion 15 is longer than the length of extending portion 18 . Flange 17 also includes openings 22 that for convenience are similarly sized and located in alignment with the openings 21 in flange 14 . Openings 22 are used to sealingly attach the spacer 10 , by the flange 17 , to the intake manifold of the internal combustion engine. Usually, the flanges 14 and 17 and the depending and extending portions of members 11 and 12 are generally square with rounded corners that coincide with the outlet of a typical carburetor. For convenience and lessening of weight, the openings 21 and 22 being in located in portions of the flanges extending outward from the corners of the square.
[0023] In one embodiment, the elastomeric member 13 comprises a hollow body portion 23 and a flange-like portion 24 extending outward from one end of the body portion 23 . This configuration of the elastomeric member 13 allows for the body portion 23 to fit within the space provided between the outside of depending portion 15 and the inside of the extending portion 18 ; and, and when the members 11 , 12 , and 13 are assembled, the end of the depending portion 15 and the end of the body portion 23 of the elastomeric member 13 are aligned with the lower end of flange 17 . Further, when assembled, the upper end of extending portion 18 is in contact with the underside of the flange-like portion 24 of the elastomeric member 13 and the upper end of the flange-like portion 24 is in contact with the underside of flange 14 . In other words, the flange-like portion 24 of elastomeric member 13 is sandwiched between the upper end of extending portion 18 and an inside surface of the flange 14 of the male member 11 . Again, the close fit of the depending portion 15 , the body 23 of the elastomeric member 13 , and extending portion 18 relative to each other provides the friction that is used to keep members 11 , 12 , and 13 assembled to each other.
[0024] The assembled configuration shown in FIG. 2 , in conjunction with the rubber-like properties of the elastomeric member 13 provide the spacer 10 with flexibility allowing the flanges 14 and 17 , and therefore members 11 and 12 , to move relative to each other in any direction. In actual tests using the inventive spacer 10 , the carburetor was observed to shake randomly in all three directions due to engine vibrations and resonances, but in accordance with the flexibility of the spacer, none, or substantially none, of the shaking was transmitted to the intake manifold.
[0025] The inventive spacer, due to the presence of the elastomeric member 13 provides for thermal insulation between the female member 12 and the male member 11 . This feature advantageously prevents heat from the engine environment from entering the male member 11 . In turn, the avoidance of such heat transfer prevents or at least diminishes any adverse effects that might cause the vaporized fuel to revert to a liquid state Thus, the heat insulating properties of the inventive spacer 10 advantageously serves to maintain the atomization and vaporization of the fuel in the fuel-oxidizer mixture and therefore prevents a power loss that would occur without the spacer 10 .
[0026] FIG. 3 illustrates another embodiment 20 of the elastomeric member of the inventive spacer 10 . In this embodiment, another flange-like portion 25 is attached to the body portion 23 , but at the end opposite of flange-like portion 24 . Flange-like portion 25 differs from flange-like portion 24 , in that it extends inward of body portion 21 . In order to accommodate the extra flange-like portion 25 , the depending portion 15 of male member 11 and the flange 17 would be configured a shown in FIG. 4 . Such configuration would allow the lower flange-like portion 25 to also be sandwiched but between the end of depending portion 15 and the upper surface of lower flange 17 . Depending on the properties of the elastomeric material, this double flange-like configuration and sandwiching can provide for more relative movement between the upper 14 and lower 17 flanges and therefore more isolation from the adverse effects of vibrations and its harmonics. The heat insulation characteristics of the embodiments of FIGS. 2 and 3 would be about equal.
[0027] Another embodiment 30 of the elastomeric member is shown in cross section in FIG. 4 . In this embodiment, the elastomeric member comprises only a body 21 . With this configuration, the sandwiching features of the previous embodiments would be eliminated and would most probably result in a loss of flexibility between the male and female members. However, a tradeoff would exist in that the embodiment of FIG. 5 would be simpler and less expensive to make.
[0028] In the embodiments of FIGS. 1-5 the length of the spacer 10 is substantially determined by the length of the depending portion 15 and the extending portion 18 , plus the thickness of the flange-like portions, if any, of the elastomeric member. FIG. 6 illustrates, in cross section, another embodiment of an isolating spacer containing an elastomeric member that serves to minimize unwanted vibrations and provides heat insulation. In this embodiment 40 , the elastomeric member 31 comprises only a body as per the embodiment 30 of FIG. 4 . However, only an upper flange 14 and a lower flange 17 are used in conjunction with the elastomeric member 31 . The hollow elastomeric member 31 is provided with a plurality of through holes 32 that are aligned with an equal number of through and aligned countersunk holes 33 and 34 in flanges 14 and 17 respectively. Bolts 35 and nuts 36 can then used to secure the elastomeric member 31 to flanges 14 and 17 . In this embodiment, the through openings 37 , 38 , and 39 , in flange 14 , elastomeric member 31 , and flange 17 , respectively, define the flow opening in the spacer embodiment of FIG. 6 . The embodiment of FIG. 5 provides the additional advantage of being able to change the length of the spacer by simply replacing the elastomeric member 31 with an elastomeric member having a different length.
[0029] In all of the above embodiments, the flow opening in the spacers is not restricted to a through opening in the flanges. The upper flange 14 can be provided with any number of different flow openings and configurations as are known in the field of modern day spacers.
[0030] When the inventive spacer 10 is to be attached to an internal combustion engine, appropriate sealing gaskets, as are known in the prior, are used to create a leak free connection to a carburetor and an intake manifold. Such gaskets can be seen in FIG. 1 , above and below the spacer 10 .
[0031] It is to be understood that the above described configuration of the inventive spacer 10 can be constructed such that the isolatoring elastomeric member and the flanges can be reversed end for end. Additionally, it matters not which member comprises the male member or the female member. All such variations are within the scope of the present invention. Of course, the internal configuration of the inventive spacer 10 is to be such that it conforms to the size of the openings in the carburetor and the intake manifold regardless of the exact construction used, even if the carburetor opening and the intake manifold opening are not the same size.
[0032] In practice, the isolating spacer serves to dampen and eliminate, or minimize the resonances and vibrations created by the engine and the engine's supporting structure. As a result, a more precise and stable fuel oxidizer mixture curve is achieved throughout the operating RPM range of the engine. In practice it is preferred that the isolator 23 is made from a polymer such as polyisoprene, although other similar materials can be used. The isolator and spacer construction perform the addition advantage of providing the fuel mixture with a heat barrier that serves to minimize changes in temperature of the fuel mixture and prevent fuel drop out as it progresses from the carburetor to the intake manifold.
[0033] While the invention has been described, disclosed, illustrated and shown in certain terms or certain embodiments or modifications which it has assumed in practice, the scope of the invention is not intended to be nor should it be deemed to be limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved. | A carburetor spacer is provided with isolation means to isolate the flow of atomized fuel from a carburetor to an intake manifold of an internal combustion engine comprising first and second hollow members fitting one inside the other and an elastomeric member interposed between said fitted hollow members. The elastomeric member also serving to thermally insulate the flow of fuel-oxidizer from heat produced by the engine. Thus, the isolation means helps prevent the fuel from reverting to a liquid state before being introduced into the cylinders of the engine and by reducing the heat input to the fuel-oxidizer mixture, less expansion of the mixture occurs before being introduced into the engine's cylinders. Less expansion means more of the mixture of the fuel-oxidizer can be input to the cylinders resulting in a greater power output by the engine. | 5 |
BACKGROUND OF THE INVENTION
In the use of thermal energy to generate power and induce temperature changes, the costs of fuel sources and the generally recognized need for conservation of energy inevitably dictate that there be increased usage of thermodynamic machines. A number of different types of these machines are known, such as Stirling cycle machines used for power and refrigeration, and Vuilleumier cycle machines used for inducing hot or cold temperatures. A different thermodynamic cycle is disclosed by the present inventor in U.S. Pat. No. 3,698,182, issued Oct. 17, 1972 for "Method And Device For Hot Gas Engine Or Gas Refrigeration Machine". A more recent development is described and claimed in a presently copending application for patent of the present inventor, entitled "Unitary Heat Engine/Heat Pump System", filed Dec. 30, 1981, Ser. No. 335,659. Systems in accordance with this invention are capable of achieving substantial improvements in energy gain and coefficient of performance (COP) in deriving thermal outputs at intermediate temperature levels.
Thermodynamic machines can be constructed to operate with good thermal efficiency, and are capable of use for heating or cooling applications, or both. They are particularly attractive for energy conservation application, as described above in conjunction with the referenced patent application, because of their versatility and adaptability. They provide new opportunities for the potential use of solar energy, waste heat, and the heat content of ambient air, water and ground sources.
A distinction should be observed, however, between machines which induce thermal energy changes by using approximately constant volume thermodynamic cycles and those machines in which substantial pressure differentials exist and work is done by a power piston against an external medium. The essentially constant volume devices are exemplified by Vuilleumier devices, which are machines for inducing temperatures, and by the systems and methods disclosed in the previously referenced patent application. The latter may be characterized as heat pumps for energy gain. In contrast, the Stirling cycle machines create significant pressure differentials across a power piston and significant change in the internal volume (per work cell in a multicylinder system) and may be distinguished as heat engines.
Constant volume devices are particularly interesting for new applications, because of their versatility and reliability. Because they do not create substantial pressure differentials, they do not present the sealing problems and mechanical load problems that arise with Stirling cycle machines, and they can be very large, as well as reliable and maintenance free over long periods. Because they employ approximately constant volume displacement, they are particularly dependent upon the temperature ratio, the internal void (dead) volume, and the effectiveness of the regenerator in the system. The temperature ratio between the hot and cold ends of the regenerator, based upon absolute temperatures, is primarily determinative of system performance, particularly in terms of specific output. At low temperature ratios (e.g. substantially less than 2 to 1) the heat density for a given design and dead volume is usually unacceptably low. However, significant amounts of thermal energy may be available from intermediate level sources at below about 300° C. If one is to realize the benefits of these constant volume systems in using the heat content from solar, ambient and waste heat sources, therefore, it becomes extremely important to confront the problem of the temperature ratio limitation. The Knoos system described in the referenced patent application, for example, shows a number of noteworthy applications of a thermodynamic system in which the coefficient of performance can be substantially improved over prior art systems with comparable inputs. The description also demonstrates, however, that the system is dependent, in terms of specific energy (heat) output, on pressure and temperature ratios. Heretofore it has not been feasible to use thermodynamic machines of the constant volume type where temperature ratios are low. The temperatures of the heat sources are established by conditions of availability and are effectively immutable; the pressure ratio that then results may be so low that the machine operates with very low efficiency and specific energy (heat) output.
SUMMARY OF THE INVENTION
Thermodynamic machines and methods in accordance with the invention significantly improve the specific energy output derivable with given, relatively low, temperature ratios by pressure ratio intensification in resonance with the operative cycle of the machine and thermal energy interchange with associated superheated and supercooled regenerator chambers. By added compression and expansion at the hot and cold ends of the machine in selected phase relation to the principal displacer elements, and by series coupling of the superheated and supercooled regenerator chambers to the regenerator, the overall temperature ratio and thus also the pressure ratio are effectively increased to different steady state levels. The specific energy output and the coefficient of performance of the machine as a whole are materially greater because the machine is placed in a more efficient operating regime.
Thermodynamic machines in which concepts of the invention may be employed are preferably, but not necessarily, of the closed gas type having approximately constant internal volume. Such machines may be variously configured to induce temperatures or to function as heat pumps for energy gain, at high, medium or low temperature levels. The nature of the thermodynamic cycle renders them dependent upon temperature conditions and the effectiveness of the regenerator. The ability to better the specific energy output, in accordance with the invention, in response to thermal inputs having low temperature differential, greatly expands the applications and uses for these systems. The moderate temperature levels that are derivable from solar energy, waste heat and other common sources may now be efficiently used in these long-life reliable systems, which can be extremely large if desired. Temperature ratios (in degrees Kelvin) of substantially less than about 1.7 and temperature levels between -20° C. (253° K) and 300° C. (573° K) provide the principal practical ranges of interest for heat pumping. Furthermore, improved coefficient of performance can be derived in different senses and with different temperature level outputs from heat pump systems. It is consequently shown that a class of thermal transformers is provided for stepping up or stepping down temperature levels with excellent coefficients of performance and practically useful specific outputs.
In one specific example of systems and methods in accordance with the invention, a constant volume thermodynamic machine has hot, cold and intermediate level working chambers with hot and cold displacers cycling working fluid through a thermal regenerator coupled to all three chambers. A compressor-expander system including oppositely moving displacers, within superheating and supercooling regenerator chambers respectively, is driven in phased relation to the principal displacers. Cyclic net compression work of hot working fluid in the superheating chamber provides temperature pumping of the hot end of the regenerator addition, which is in direct series with the hot end of the regenerator. Concurrently at the cold end of the regenerator the cyclic net work of expansion in the supercooling chamber provides a supercooled temperature for that regenerator portion, and the process experiences a larger than normal temperature ratio. These factors translate over a full cycle into a greater pressure-volume area on the indicator diagram for the machine, and hence a greater specific energy output. By selection of the phase angle between each hot or cold displacer and its associated pressure ratio intensifying displacer, and by choice of the efficiency of the associated superheating or supercooling regenerator section, losses present in the regenerator additions are compensated and suitable steady state superheating and supercooling levels are achieved.
Among the features of the invention are the fact that thermal outputs can be derived, with significant energy gain (heat pump coefficient of performance), at the intermediate level while providing thermal inputs at the hot and cold levels which are not widely different. Moreover, an inverse function may be exercised, with thermal input being provided at the intermediate level and heating or cooling outputs being derived from the hot and cold levels respectively. When used as a thermal transformer, such a system can receive thermal energy transmitted from a source at one temperature level (e.g. superheated water or steam) and convert it, with a certain coefficient of performance (primarily dictated by the laws of thermodynamics and maximized to Carnot-process values) from an ambient sink to a different level.
Systems in accordance with the invention may be mechanized in a number of ways, which may be varied with the application. Thus the compressor/expander arrangement may be a single, double ended piston within a single cylinder, or provided by a pair of separate pistons which may in fact be in line with the basic displacers of the thermodynamic machine. Alternatively, the added regenerator and displacer functions over the basic device may be provided by a single, multi-section, reciprocating displacer-regenerator structure. The principles of the invention may also be used with benefit in heat engine systems, such as Stirling machines in which substantial piston pressure differentials are created during cycling. With superheating and supercooling of the hot working fluid and cold working fluid respectively, a higher power density can be achieved and also the regenerator inefficiency possibly reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may be better understood by reference to the following description, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a combined schematic and perspective view, partially broken away, of a system in accordance with the invention employing pressure ratio intensification;
FIG. 2 is a diagrammatic representation of pressure variations in the various working chambers in the system of FIG. 1;
FIG. 3 is a diagrammatic representation of pressure cycle variations in the system of FIG. 1 depicting the difference between conventional operation and operation using pressure ratio intensification;
FIG. 4 is a diagrammatic representation of variations in pressure vs. volume for both conventional operation and operation using pressure ratio intensification;
FIG. 5 is an indicator diagram of pressure vs. volume relationships existing in a portion of a pressure ratio intensification system;
FIG. 6 is an energy diagram showing the qualitative character of thermal energy flows in the system of FIG. 1;
FIG. 7 is a combined schematic and perspective representation of a different system using pressure ratio intensification in accordance with the invention;
FIG. 8 is a schematic representation of yet another example of a system using pressure ratio intensification to provide thermal gain in transforming thermal energy from a central source to local use;
FIG. 9 is a diagrammatic representation of a thermal transformer application using systems in accordance with the invention;
FIG. 10 is a diagrammatic representation of a second thermal transformer application using systems in accordance with the invention;
FIG. 11 is a combined schematic and sectional view of a different system using pressure ratio intensification in accordance with the invention;
FIG. 12 is a schematic representation of yet another system using pressure ratio intensification in accordance with the invention; and
FIG. 13 is an indicator diagram showing pressure vs. volume relationships in the system of FIG. 12 in contrast to conventional conditions.
DETAILED DESCRIPTION OF THE INVENTION
An improved constant volume thermodynamic machine is depicted in general and schematic fashion in FIG. 1, to which reference is now made. It is a solar-driven refrigeration system/heat pump. As described in the above referenced Knoos application, Ser. No. 335,659, an integral heat engine/heat pump 10 is depicted in simplified form in this example and includes a housing 12 within which a hot working chamber 14, a cold working chamber 16 and an intermediate temperature level working chamber 18 are disposed. A hot displacer 20 and a cold displacer 22 are reciprocated within the cylindrical housing 12 by a displacer driver system 24, and in phased relationship to each other as described hereafter.
Shunting the working chambers and forming a part of the thermodynamic machine 10 is a regenerator 30 which has a hot temperature level 31, an intermediate temperature level 32 and a cold temperature level 33 between which the heat retaining mesh, particulate or fibers of the regenerator are disposed in conventional fashion. In this regenerator 30, however, a superheating extension 35 and a supercooling extension 36 are coupled in serial fashion to the opposite ends and comprise interior regenerator sections that are in communication with the principal interior body of the regenerator 30. A superheated level 38 and a supercooled level 39 at each end of the regenerator 30 are coupled to the opposite ends (designated hh and cc respectively) of a compressor/expander chamber 40 within which a double ended displacer 42 is reciprocated by a displacer drive system 44. The displacer drive system 44 reciprocates the displacer 42 in a phased relation, described in greater detail hereafter, relative to the cyclic movement of the displacers 20, 22 in the cylindrical chamber 12.
The regenerator extensions 35, 36 are high efficiency units, and in accordance with regenerator designs for thermodynamic machines preferably have a thermal efficiency in excess of 99%. This can be achieved for example by stacking fine mesh screens having typical diameters in the range of 0.02 to 0.08 mm. The displacer drive systems 24, 44 are not required to consume a substantial amount of mechanical energy inasmuch as the displacers are not required to act against substantial gas pressure differences and at any point in time the gas pressure within the system is substantially equal, apart from pressure losses and friction losses in the various conduits.
The conduits interconnecting the cold, hot and intermediate level working chambers 14, 16 and 18 respectively to their corresponding temperature level openings 33, 32 and 31 respectively in the regenerator 30 are made through external heat exchangers. In the present example it is desired to provide thermal inputs to the thermodynamic machine 10 at the cold and hot ends, and to reject thermal energy at the intermediate level. Accordingly, the cold working chamber 12 and the cold temperature level 33 of the regenerator 30 are coupled to one side of a cold level (CX) heat exchanger 50 which has counter- and concurrent-flow or cross-flow passageways for receiving thermal energy from the refrigeration load, carried by air or a liquid, for example, typically in the range of -10° to +30° C. Between the hot temperature level 31 of the regenerator 30 and the hot working chamber 14, the intercoupling conduit is passed through a hot level (HX) heat exchanger 52, with the heat source flow being derived from a heating system 54. The heating system 54 comprises in this example a bank of parabolic tracking solar collector systems 56, 57, 58, and it will be understood that one or a substantial number may be utilized dependent upon the thermal capacity of the thermodynamic machine. Flow is established through the hot level heat exchanger 52 by a pump 60.
At the intermediate temperature level, heat is rejected, e.g. to ambient air, from an intermediate level heat exchanger 62 (designated MX), through the counterflowing or cross-flowing passageways of which a fluid flows to a utilization device (not shown). Temperatures at the hot level heat exchanger 52 are of a moderately elevated level, in the range of 230° to 290° C. in this example. Temperature level from the MX exchanger 62 is typically in the range of 40° to 60° C. Those skilled in the art will recognize that the temperature levels at the two thermal inputs are readily realizable and may be provided from a number of alternative sources in addition to those mentioned. For example, at the hot end of a machine, the thermal energy may be in the form of waste heat from an industrial process or heat rejected from a power plant.
In the operation of the system of FIG. 1, the operative considerations mentioned in the previously referenced patent application are generally applicable. They are, however, modified in accordance with the invention so that a significant refrigeration load in relation to the solar heat input can still be obtained even though the temperature ratio is less than approximately 1.7, taking the ratio of the values of the temperatures in the hot chamber 14 and cold chamber 16 stated in degrees Kelvin. Even a highly efficient regenerator becomes insufficiently effective when the temperature ratio is low and pressure ratio is approaching unity. The degree of regeneration effectiveness is crucial to the essentially constant-volume thermodynamic process particularly since the pressure-volume integral in the PV indicator diagram is generally small and determined solely by these thermodynamic considerations. In the system of FIG. 1, referring to FIG. 2 as well as to FIG. 1, the cycling of the hot "upper" displacer 20 is shown in phase relation to the cycling of the cold "lower" displacer 22, with the cold displacer leading in phase so as to provide pressure profiles as shown. For these pressure profiles, the pressure minimums exist when the displacers 20, 22 are near their top positions, and pressure maximums exist when the displacers 20, 22 are near their bottom positions. Further, the pressure is high when the volume of the hot chamber 14 increases, and the pressure is low when the volume of that chamber decreases. This allows for a cyclic net expansion of gas in the hot chamber and a heat load into the hot level heat (HX) exchanger 52 for steady state conditions to persist. Thus there is a positive thermal energy flow, Q h , into the thermodynamic machine 10, using the convention that the thermal energy flow is positive when it flows into the machine.
The pressure profiles in the hot and cold working chambers 14, 16 do not quantify the pressure ratio because the base line is not represented. However, it will be recognized that the pressure ratio may typically be 1.1 or less with a temperature ratio of 1.7 or less, depending upon the ineffectiveness of the regenerator 30 and the amount of void space in the machine. In accordance with the invention, however, an integrally related thermodynamic process is utilized to achieve what may be called "pressure ratio intensification" (PRI). As shown in the lower diagram of FIG. 2, the double ended displacer 42 of FIG. 1 is reciprocated in synchronism and chosen phase relation with the hot and cold displacers 20, 22. The phase relationship chosen is one in which the double ended displacer 42 is near its top position when the pressure is minimum and the hot and cold displacers 20, 22 are near their top position, so that working fluid is pushed into the supercooled chamber, designated cc, adjacent the bottom end of the displacer 42. Conversely, the displacer 42 is near its bottom position when the system pressure is maximum, and the displacers 20, 22 are near their bottom position. At this time gas is pushed into the superheated chamber hh adjacent the top end of the displacer 42. By this arrangement, the chambers hh and cc are always varied in volume precisely 180° out of phase, and in resonance with the cycling of the remainder of the system. The extent and sense of the phase shift between the double ended displacer 42 and the hot and cold displacers 20, 22 is chosen to provide a P-V cycle in the hh and cc chambers that tends to heat the hh chamber above the hot chamber 14 level, and cool the cc chamber below the cold chamber 16 level. Thus the hh chamber may be said to be "superheated", and the cc chamber may be said to be "supercooled" with the result that the temperature ratio across the length of the regenerator 30, including the superheated and supercooled ends 38, 39 and the extensions 35 and 36 is increased. The net superheating and supercooling effect at each end, however, is only sufficient to overcome thermal energy losses in the regenerator extensions 35, 36 so that steady state conditions are achieved at each end of the regenerator 30. With the temperature ratio at the regenerator 30 thus increased, the ineffectiveness of the regenerator is of less importance, and the apparent pressure ratio at the thermodynamic machine 10 is effectively increased. For example, the constant-volume machine with a pressure ratio of 1.1 to 1 may be increased to the range of between 1.2 and 1.3 to 1.
It should be noted that the thermal efficiency of the regenerator extensions 35, 36 as well as the phase shift angle between the double ended displacer 42 and the hot and cold displacers 20, 22 are considered together in determining the superheated and supercooled temperature levels hh and cc established in the steady state.
A comparative depiction of the effect of pressure ratio intensification on working fluid pressure in a constant-volume machine is shown in FIG. 3, in that the pressure swings with PRI are substantially greater than those of the conventional machine. This carries over, as seen in FIG. 4, directly into an increase in power density of the machine, because the P-V indicator diagram is expanded with PRI to a greater included (integral) area per cycle. In effect, the very small amount of work input needed to reciprocate the displacer for superheating and supercooling is more than adequately compensated for by the improvement in thermal interchanges within the cycle.
The work input required to the added displacer to achieve superheating and supercooling is under the stated conditions typically substantially less than the heat loads with which the system cooperates. The double ended displacer 42 preserves the constant volume nature of the system and the phase angle variations are sufficiently small that the P-V indicator diagrams and the hh and cc chambers have small included (integral) areas, as shown in FIG. 5. The superheating cycle as shown by the counterclockwise curve in FIG. 5 (negative P-V integral value), and the supercooling cycle as shown by the clockwise curve in FIG. 5 (positive P-V integral value) are approximately anti-symmetrical in nature.
The quantitative and relative temperature levels of the various thermal energy exchanges may be depicted in general form as seen in FIG. 6. Heat energy flows into the machine at the hot temperature T h (into the hot level heat exchanger 52) and at the cold temperature T c (into the cold level heat exchanger 50). Heat energy is rejected to ambient at the intermediate level T m , the exchange being designated -Q m , because thermal energy flows out of the machine. It will be evident to those skilled in the art that the refrigeration level T c is generated with improved COP because of the use of ambient temperature levels in this heat pump system.
A number of significant advantages and applications are derived from these concepts. As is shown below, the constant-volume thermodynamic cycles may be utilized where temperature levels are highly useful to human habitations and processes, but involve temperature ratios that have heretofore rendered them uneconomic. Moreover, it now becomes practically feasible under certain conditions to shift the temperature level of a heated mass, with an associated thermal gain factor, (limited by Carnot-process values) in what may be termed a "thermal transformer".
For example, referring now to FIG. 7, in which portions of the system corresponding to the arrangement of FIG. 1 are similarly numbered, a heat pump application is provided that is the inverse of the previously disclosed system. In FIG. 7, the thermal input is at a moderate temperature level such as in the range of 40° to 60° C., being derived from a bank 68 of flat plate solar collector panels 69. At this temperature level, the heat pump will not, without PRI, induce hot and cold temperature levels adequate to provide sufficient energy density to be of interest. With pressure ratio intensification, however, the head load levels become meaningful. For this purpose the thermodynamic machine includes a combined displacer and regenerator 70, in which a superheated chamber 72 at the upper end and a supercooled chamber 74 at the lower end are separated by a sequence of four regenerator sections 76, 77, 78 and 79, with the upper and lower regenerator sections 76 and 79 comprising the regenerator extensions. The side walls of the regenerator sections are bounded by thermal insulators 80. The intermediate sections 77 and 78 are bounded by an upper or hot temperature level chamber 82 and a lower or cold temperature level chamber 84 and jointly accessible to an intermediate level chamber 86, each of which is connected by conduits through the appropriate heat chamber to the corresponding section in the displacer system. Again, the reciprocating regenerator sections 76 to 79 cause displacement of the working fluid in phased relation to the movement of the displacers 20, 22, but the phase angle relationship is varied to account for the fact that thermal outputs are to be derived at the hot and cold ends.
At the hot end, the hot level heat exchanger 52 is in communication with an external thermal storage 90, which stores a hot liquid 92 as shown, but the heat exchanger 52 may alternatively be coupled to a two-phase system having a suitably high heat of fusion, or it may incorporate some other form of thermal storage. FIG. 7 shows a pump 94 providing circulation into the pure liquid thermal storage, from which hot liquid may be withdrawn for use in an intended application.
With this system, the hot level output is lifted to the range of approximately 95° C., and the heat rejected to the ambient sink system at the cold level heat exchanger 50 is in the range of -10° to +30° C. Accordingly, the heat pump functions in a fashion suitable for water heating at the hot level.
In the system shown in FIG. 7, the thermal transformer operation involves a temperature shift from T m up to T h with a thermal gain factor -Q h /Q m less than unity. In the example of FIG. 8, to which reference is now made, the thermal transformer effect is utilized in conjunction with central heating with an energy gain factor COP≡-Q m /Q h =coefficient of performance larger than one. Where a central source of heat, such as superheated water under a pressure of 150° C. is provided as high temperature input on a long length conduit 100, it is desired to provide output fluid at a lower temperature level useful for residential heating, with a coefficient of performance giving an energy gain substantially greater than 1.0. For each local installation, a different heat pump 102, 104 is employed that is coupled to the hot pressurized source line 100 and receives heat from an ambient source in the range of -10° to 15°. Each local installation therefore can extract energy with thermal gain (high COP) from the common line 100. With the usage of PRI, the energy density becomes desirably high, as well as the COP, despite the low temperature ratio and the relatively small temperature range that is involved.
Using pairs of pressure ratio intensified heat pumps in complementary fashion, as shown in FIGS. 9 and 10, thermal energy may be shifted from one temperature level to another more suitable for purposes of long line transmission. In FIG. 9, thermal energy at an intermediate temperature level Tm 1 is transformed in the first heat pump with PRI 110 to an output at a higher temperature level Th 1 for transmission on a closed line 112 (the return line being shown in dotted lines) to a second heat pump (also with pressure ratio intensification) 114. At the second heat pump 114 the temperature of the incoming hot fluid is somewhat reduced to the level Th 2 because of thermal losses, but the output at level Tm 2 is derived with energy gain (COP>1.0). Thus, in the first heat pump 110 waste heat below 100° C. can be the input, with the high temperature exchanger being a boiler, and with forward transmission to the second heat pump 114 being of pressurized steam above 100° C. At the second heat pump 114 the high temperature exchanger condenses the steam during generation of the thermal output Tm 2 . The transmission line between the heat pumps may also be an open line, without a return, in which event the overall efficiency is lower in principle and the fluid in the high temperature line can be dumped at the second heat pump, or utilized as a waste heat application, or alternatively combined with the Tm 2 output.
In the system of FIG. 10, a pair of heat pumps with pressure ratio intensification which may be regarded as thermal transformers 120, 124 are again intercoupled by a transmission line 122, with the return line being shown as dashed lines (although the system could again with less efficiency be open). In this instance the transmission line may be required to transport thermal energy from a distant power station which generates waste heat, e.g. superheated steam at 150° C. and elevated pressure. If the length of a direct transmission line for this temperature level makes it inordinately expensive for this application, the thermal transformer systems 120, 124 are utilized to step down from the input level Th 1 at the source, and then to step back up to the output level Th 2 for local use. The thermal energy can then be transmitted by liquid water below 100° C. and atmospheric pressure levels, so that less expensive piping and less thermal insulation is required,. Other two-phase systems, such as ammonia, may be used for still lower temperature levels, transmitted in gaseous form in the lines, and returned in liquid form.
Thermodynamic machines in accordance with the invention make possible the use of a number of different displacing and regenerative devices, one combination of which is shown in FIG. 11. Here the displacer drive system 130 operates to reciprocate displacers in first and second cylinders 132, 134 respectively. In the first cylinder 132, a hot displacer 136 and a PRI displacer 138 are coupled by separate drive mechanisms, indicated schematically, to the displacer drive system 130 and moved synchronously with a given phase relation between them as previously described. The cross-sectional area of the chamber 132 and the displacers 136 and 138 may be made substantially different to provide a differential relative to the other cylinder 134, as shown by the dashed line enlargement. In the second cylinder 134, the cold displacer 140 and the associated pressure ratio intensification displacer 142 are also moved in specific phase relationships to each other and to the hot displacer 136, with the displacer 142 associated with the cc chamber being substantially 180° out of phase with the opposite displacer 138 associated with the hh chamber. Superheating and supercooling in the regenerator extensions again take place, with consequent enhancement of the temperature ratio and improvement of the energy output density. The phase relationships may be selected in accordance with the direction of energy transfer.
Also in FIG. 11 there is depicted a radial-flow regenerator 150 having end input ports 151, 152 communicating with the hh and cc chambers respectively. The walls of the regenerator 150 may be of an insulating material (e.g. ceramic) as may interior core elements 154, 155 minimizing dead volume. Concentric with the central axis of the cylindrical regenerator 150, end regenerator rings 156, 159 constitute the regenerator extensions. The intermediate regenerator rings 157, 158 define the hot, intermediate and cold levels of the regenerator, to which separate ports 162, 163, 164 extending from the side wall of the regenerator body 150 are coupled. Only the intermediate port 163 is coupled to the interior of the volume, within the inner radius of the intermediate rings 157, 158.
With the arrangement of FIG. 11, not only may the relative cross-sectional areas of the cylinders 132, 134 be made to differ, but the stroke lengths may also be varied more readily if desired. It should be noted that while the instantaneous volume of the intermediate chamber is defined by the opposing faces of the two moving piston displacers 136, 140, the hot and cold working chambers are defined by two opposed moving faces as well, although this does not prevent the establishment of harmonic motion.
A Stirling engine system 170 in accordance with the invention is depicted in simplified form in FIG. 12 as an inline, single cylinder 172 device including a Stirling engine displacer 174 and power piston 176, the upper surfaces of which act against a hot chamber 178 and a cold chamber 179 respectively. A buffer chamber 180 communicates with the opposite side of the power piston 176 from the cold chamber 179. A connecting link mechanism 182 couples the power piston to a power output device 184 which also is coupled by a separate linkage 186 to drive the displacer 174 in phased relationship to the power piston. A regenerator 190 is coupled to one set of passages in a HX heat exchanger 192, the same passages also communicating with the hot chamber 178. Similarly, a CX heat exchanger 194 intercouples the cold temperature level section of the regenerator 190 to the cold chamber 179. A moderate temperature heat source providing thermal energy Q h input to the hot level temperature heat exchanger 192 provides thermal energy for the system while thermal output -Q c (heat rejection) is derived from the cold level temperature heat exchanger 194. A superheated regenerator extension 196 and a supercooled regenerator extension 198 are coupled in series to the intermediate portion of the regenerator 190, and communicate with the hh and cc chambers at the opposite ends of a PRI displacer 200 within a cylindrical chamber 202. A displacer drive 204 coupled to the displacer 200 reciprocates the displacer in a selected phase relationship to the power piston 176.
For brevity and simplicity, the Stirling engine that is depicted is less complicated than the double acting, four cylinder arrangements currently most often in use. With such arrangements, it will be recognized that each subsystem must have its own pressure ratio intensification mechanism, i.e. four PRI devices.
A Stirling engine operated with a low temperature heat source typically provides such low specific power output (kilowatt/engine displacement) that it cannot be productively used. By low temperature heat source is meant a source such as a 300° C. or lower temperature level generated from a concentrator type of solar collector bank. Although the Stirling engine does generate substantial compression ratio under these conditions, the indicator (P-V) diagrams are too thin and pressure ratio intensification can be of substantial benefit. As seen in FIG. 13, the P-V indicator diagram becomes wider, the power density increases, and because of the reduction in the inefficiency of the regenerator the overall efficiency of the engine could also be improved.
Although a number of forms and modifications in accordance with the invention have been described, it will be appreciated that a wide range of alternative systems and methods may be employed, and encompassed within the appended claims. | In thermodynamic apparatus and methods utilizing constant volume cycling devices, substantial improvements in energy output can be gained by utilization of an integrated thermodynamic process placing regenerator efficiency in a higher regime. Displacer elements operating in phased relation to the thermodynamic cycle provide superheating and supercooling to extended opposite ends of the regenerator, to establish steady state conditions which increase the temperature ratio of the system. In turn, the pressure ratio of the thermodynamic cycle is increased and the specific energy output improved. This expansion of the capability of thermodynamic machines for working in moderate temperature ranges is further utilized with systems for achieving thermal gain for heating or cooling, utilizing ambient energy as a heat source as well. It thus becomes feasible to effect thermal transformation between different temperature levels with high coefficients of performance, vastly increasing the number of alternatives available for practical thermal exchange systems. | 5 |
TECHNICAL FIELD
[0001] The present invention relates to a binder composition for a lithium-ion secondary battery electrode.
BACKGROUND ART
[0002] Demand for an electrochemical device such as a lithium-ion secondary battery has been rapidly increased by taking advantage of a small size, a light weight, a high energy density, and a characteristic capable of being charged and discharged repeatedly. The lithium-ion secondary battery is used in a portable terminal such as a cellular phone or a notebook personal computer because of a relatively large energy density. The lithium-ion secondary battery used as a power source of such a portable terminal is a small lithium-ion secondary battery. On the other hand, a large lithium-ion secondary battery is used for a power source of an electric automobile or the like. Applications of a lithium-ion secondary battery are expanding as described above. However, higher performance such as a higher capacity, a higher potential, or a higher durability is required at the same time.
[0003] For higher performance of a lithium-ion secondary battery, improvement of an electrode, an electrolytic solution, and another battery component has been studied. Among these components, an electrode is usually manufactured by mixing an electrode active material with a liquid composition obtained by dispersing or dissolving a polymer serving as a binder in a solvent to obtain a slurry composition, applying the slurry composition onto a current collector, and drying the slurry composition. In an electrode manufactured by such a method, it has been tried to achieve higher performance of a secondary battery by improving a binder (for example, refer to Patent Literature 1).
CITATION LIST
Patent Literature
Patent Literature 1: JP 2012-14920 A
SUMMARY OF INVENTION
Technical Problem
[0004] However, demand for performance of a lithium-ion secondary battery has become more and more sophisticated recently. Improvement of response at the time of abnormality has been particularly demanded in addition to an original battery characteristic such as a cycle characteristic or a discharge rate characteristic.
[0005] The present invention has been achieved in view of the above problems. An object thereof is to provide a binder composition for a lithium-ion secondary battery electrode capable of lowering charge/discharge performance in cases when a battery abnormally generates heat or is in an abnormally high-temperature environment.
Solution to Problem
[0006] The present inventors made intensive studies in order to solve the above problems. As a result, the present inventors have found that a lithium-ion secondary battery having an excellent characteristic against an abnormal temperature can be achieved by using a predetermined composite polymer particle as a binder, and have completed the present invention.
[0007] That is, the present invention provides:
[0008] (1) a binder composition for a lithium-ion secondary battery electrode, containing a composite polymer particle obtained by polymerizing a monomer solution containing a polymer in an aqueous medium;
[0009] (2) the binder composition for a lithium-ion secondary battery electrode described in (1), in which the polymer is manufactured by a solution polymerization method, the monomer solution is obtained by dissolving the polymer in a monomer, and the composite polymer particle is obtained by subjecting the monomer solution to suspension polymerization or emulsion polymerization in an aqueous medium;
[0010] (3) the binder composition for a lithium-ion secondary battery electrode described in (1) or (2), in which the polymer is manufactured by a solution polymerization method, the monomer solution is obtained by dissolving the polymer in an amount of 5 to 100 parts by weight with respect to 100 parts by weight of a monomer, and the composite polymer particle is obtained by subjecting the monomer solution to suspension polymerization or emulsion polymerization in an aqueous medium;
[0011] (4) the binder composition for a lithium-ion secondary battery electrode described in (2) or (3), in which the polymer manufactured by the solution polymerization method is an olefin polymer;
[0012] (5) the binder composition for a lithium-ion secondary battery electrode described in any one of (2) to (4), in which the polymer manufactured by the solution polymerization method is a block copolymer;
[0013] (6) the binder composition for a lithium-ion secondary battery electrode described in any one of (2) to (5), in which the polymer manufactured by the solution polymerization method has a melting point in a range of 50° C. to 150° C.; and
[0014] (7) the binder composition for a lithium-ion secondary battery electrode described in any one of (1) to (6), in which the composite polymer particle has a core-shell structure in which a shell portion containing a polymer having a binding property is further formed on a surface of the composite polymer particle.
Advantageous Effects of Invention
[0015] The binder composition for a lithium-ion secondary battery electrode according to the present invention can lower charge/discharge performance in cases when a battery abnormally generates heat or is in an abnormally high-temperature environment.
DESCRIPTION OF EMBODIMENTS
[0016] Hereinafter, a binder composition for a lithium-ion secondary battery electrode according to the present invention will be described. The binder composition for a lithium-ion secondary battery electrode (hereinafter, also referred to as “binder composition”) according to the present invention contains a composite polymer particle obtained by polymerizing a monomer solution containing a polymer in an aqueous medium.
[0017] (Composite Polymer Particle)
[0018] The composite polymer particle is obtained by polymerizing a monomer solution containing a polymer in an aqueous medium.
[0019] (Polymer)
[0020] As the polymer contained in the monomer solution, used for manufacturing the composite polymer particle, a temperature-sensitive polymer changing characteristics thereof in a specific temperature range is used. The temperature-sensitive polymer preferably has an inflection point in change of a volume or an inflection point of an elastic modulus due to a temperature in a range of 50° C. to 150° C. Specifically, a polymer having a melting point of 50° C. to 150° C. or a polymer having a large linear expansion coefficient or changing the linear expansion coefficient in a range of 50° C. to 150° C. is preferable. Particularly, a polymer polymerized by a solution polymerization method (hereinafter, also referred to as “solution polymerized polymer”) is preferably used. Here, the solution polymerization method is a method for polymerizing a mixture of one or more kinds of monomers in an organic solvent.
[0021] In the present invention, the polymer having the above characteristics is preferably dissolved in a monomer. Therefore, the polymer is preferably a polymer which can be dissolved in a monomer which can be subjected to emulsion polymerization or suspension polymerization in water.
[0022] As such a polymer, an olefin polymer can be preferably used, and a polymer obtained by hydrogenating a carbon-carbon double bond in a main chain of a copolymer of an aromatic vinyl compound and a conjugated diene compound can be more preferably used. A hydrogenation ratio of a double bond in the main chain is 50% or more, preferably 80% or more, and more preferably 90% or more.
[0023] Examples of the aromatic vinyl compound include a styrene compound such as styrene, α-methylstyrene, β-methylstyrene, p-t-butylstyrene, or chlorostyrene. Also, the aromatic vinyl compound may be used singly or in combination of two or more kinds thereof at any ratio.
[0024] More specific examples of the polymer include a polymer obtained by copolymerizing another monomer with styrene as a main component. The ratio of the aromatic vinyl compound in the polymer is preferably 5% by weight or more, more preferably 10% by weight or more, and particularly preferably 20% by weight or more.
[0025] Examples of the conjugated diene compound include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, and piperylenee. Among these compounds, 1,3-butadiene, isoprene, and 2,3-dimethyl-1,3-butadiene are preferable, and 1,3-butadiene is particularly preferable. Further, the conjugated diene compound may be used singly or in combination of two or more kinds thereof at any ratio.
[0026] The ratio of the conjugated diene compound in the polymer is preferably 10% by weight or more, more preferably 20% by weight or more, particularly preferably 30% by weight or more, preferably 90% by weight or less, more preferably 80% by weight or less, and particularly preferably 60% by weight or less.
[0027] Further, a copolymer of an aromatic vinyl compound and a conjugated diene compound can be also used. The weight ratio between the aromatic vinyl compound and the conjugated diene compound (aromatic vinyl compound/conjugated diene compound) is preferably 42/58 or more, more preferably 49/51 or more, particularly preferably 55/45 or more, preferably 87/13 or less, more preferably 80/20 or less, and particularly preferably 70/30 or less.
[0028] As the polymer of the conjugated diene compound, either a random copolymer or a block copolymer can be used, but the block copolymer is preferable. A bonding mode of the block copolymer of the conjugated diene compound is appropriately selected, for example, from a diblock copolymer, a triblock copolymer, a tetrablock copolymer, and a pentablock copolymer according to an intended use.
[0029] Specific examples of such a block copolymer include a styrene-isobutylene-styrene block copolymer (SIBS), a styrene-ethylene-butylene-styrene block copolymer (SEBS), and a styrene-ethylene-propylene-styrene block copolymer (SEPS). Among these copolymers, a styrene-ethylene-butylene-styrene block copolymer (SEBS) is preferably used. Note that, a method for manufacturing a block copolymer is not particularly limited, but the block copolymer may be manufactured by a known method.
[0030] (Monomer)
[0031] A monomer used in the monomer solution in the present invention is not particularly limited, but can be selected appropriately according to the kind of the polymer. In the present invention, as a monomer, styrene, p-methyl styrene, α-methyl styrene, or the like can be preferably used, and styrene is more preferably used. These monomers may be used singly or in combination of two or more kinds thereof.
[0032] (Method for Manufacturing Composite Polymer Particle)
[0033] The composite polymer particle is obtained by polymerizing a monomer solution containing the above-mentioned polymer in an aqueous medium. The composite polymer particle is preferably obtained by polymerizing the monomer solution having a polymer dissolved in a monomer in an aqueous medium. The monomer in the monomer solution is polymerized by polymerization, and therefore the composite polymer particle is obtained while being dispersed in an aqueous medium.
[0034] A polymerization method is not limited as long as a desired composite polymer particle is obtained. However, polymerization is performed by an emulsion polymerization method or a suspension polymerization method.
[0035] The emulsion polymerization method is usually performed according to a conventional method. For example, the emulsion polymerization method is performed according to a method described in “Experimental Chemistry” Vol. 28, (Publisher: Maruzen Co., Ltd., edited by the Chemical Society of Japan). That is, this is a method for putting water, a dispersing agent, an emulsifier, an additive such as a crosslinking agent, a polymerization initiator, and a monomer solution in a sealed container equipped with a stirrer and a heating device so as to obtain a predetermined composition, emulsifying a monomer or the like in water by stirring the composition in the container, and initiating polymerization by raising the temperature under stirring. Alternatively, this is a method for putting the composition in a sealed container after the composition is emulsified, and initiating a reaction similarly.
[0036] In addition, the suspension polymerization method is a method for performing polymerization by suspending the composition in an aqueous medium in the presence of a dispersing agent dissolved in the aqueous medium.
[0037] Here, the aqueous medium is a medium containing water. Specific examples thereof include water, ketones, alcohols, glycols, glycol ethers, ethers, and a mixture thereof.
[0038] Further, the monomer solution used for the polymerization preferably contains a polymer in an amount of 5 to 100 parts by weight with respect to 100 parts by weight of a monomer.
[0039] As a surfactant used in an emulsion polymerization or suspension polymerization method, any surfactant can be used as long as a desired composite polymer particle is obtained. Examples thereof include sodium dodecylbenzene sulfonate, sodium lauryl sulfate, sodium dodecyl diphenyl ether disulfonate, and dialkyl succinate sodium sulfonate. For example, a reactive emulsifier having an unsaturated bond may be used. Among these compounds, sodium dodecyl diphenyl ether disulfonate is preferable from viewpoints of excellent versatility in manufacturing and the small amount of bubbles generated. The surfactant may be used singly or in combination of two or more kinds thereof at any ratio.
[0040] Any amount of the surfactant can be used as long as a desired composite polymer particle is obtained. The amount is preferably 0.5 parts by weight or more, more preferably 1 part by weight or more, preferably 10 parts by weight or less, and more preferably 5 parts by weight or less with respect to 100 parts by weight of the monomer solution.
[0041] Further, in a polymerization reaction, a polymerization initiator is usually used. As the polymerization initiator, any polymerization initiator can be used as long as a desired composite polymer particle is obtained. Examples thereof include sodium persulfate (NaPS), ammonium persulfate (APS), and potassium persulfate (KPS). Among these compounds, sodium persulfate and ammonium persulfate are preferable, and ammonium persulfate is more preferable. By using ammonium persulfate or sodium persulfate as a polymerization initiator, it is possible to suppress a decrease in a cycle characteristic of a lithium-ion secondary battery obtained.
[0042] Further, in polymerization, a polymerization system may include a molecular weight regulator or a chain transfer agent. Examples of the molecular weight regulator or the chain transfer agent include an alkyl mercaptan such as n-hexyl mercaptan, n-octyl mercaptan, t-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, or n-stearyl mercaptan; a xanthogen compound such as dimethylxanthogen disulfide or diisopropylxanthogen disulfide; terpinolene; a thiuram compound such as tetramethyl thiuram disulfide, tetraethyl thiuram disulfide, or tetramethylthiuram monosulfide; a phenol compound such as 2,6-di-t-butyl-4-methyl phenol or styrenated phenol; an allyl compound such as allyl alcohol; a halogenated hydrocarbon compound such as dichloromethane, dibromomethane, or carbon tetrabromide; thioglycolic acid, thiomalic acid, 2-ethylhexyl thioglycolate, diphenylethylene, and α-methyl styrene dimer. Among these compounds, an alkyl mercaptan is preferable, and t-dodecyl mercaptan is more preferable from a viewpoint of suppressing a side reaction. These compounds may be used singly or in combination of two or more kinds thereof at any ratio.
[0043] (Physical Properties of Composite Polymer Particle)
[0044] The number average particle diameter of the composite polymer particle is preferably 50 nm or more, more preferably 70 nm or more, preferably 500 nm or less, and more preferably 400 nm or less from a viewpoint of excellent strength and flexibility of an electrode.
[0045] (Composite Polymer Particle Having Core-Shell Structure)
[0046] When a composite polymer particle itself obtained by polymerizing a monomer solution containing a polymer in an aqueous medium does not have a binding property with an electrode active material or has an insufficient binding property, a shell portion containing a polymer having a binding property may be formed on a surface of the composite polymer particle in order to impart a binding property.
[0047] That is, in this case, a composite polymer particle having a core-shell structure, containing a composite polymer particle obtained by polymerizing a monomer solution containing a polymer (preferably, a solution polymerization polymer) in an aqueous medium as a core portion and containing a polymer having a binding property as a shell portion is obtained.
[0048] Here, as the core-shell structure, the shell portion may completely cover the core portion so as to wrap the core portion, or may partially cover the core portion.
[0049] Examples of a polymer which can be used for the shell portion include an acrylic polymer and a conjugated diene polymer.
[0050] (Acrylic Polymer)
[0051] The acrylic polymer is a polymer including a monomer unit, obtained by polymerizing a (meth)acrylate compound. Examples of the polymer include a homopolymer of a (meth)acrylate compound and a copolymer of the (meth)acrylate compound and a monomer copolymerizable therewith. By using a polymer of the (meth)acrylate compound, a binding property of the composite polymer particle can be enhanced. Note that, the term “(meth)acrylic” means acrylic or methacrylic in the present invention.
[0052] Examples of the (meth)acrylate compound include an alkyl acrylate such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, pentyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, lauryl acrylate, n-tetradecyl acrylate, stearyl acrylate, 2-ethylhexyl acrylate, 2-methoxyethyl acrylate, or 2-ethoxyethyl acrylate; a 2-(perfluoroalkyl) ethyl acrylate such as 2-(perfluorobutyl) ethyl acrylate, or 2-(perfluoropentyl) ethyl acrylate; an alkyl methacrylate such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, lauryl methacrylate, tridecyl methacrylate, n-tetradecyl methacrylate, stearyl methacrylate, or 2-ethylhexyl methacrylate; a 2-(perfluoroalkyl) ethyl methacrylate such as 2-(perfluorobutyl) ethyl methacrylate, 2-(perfluoropentyl) ethyl methacrylate, or 2-(perfluoroalkyl) ethyl methacrylate; benzyl acrylate; and benzyl methacrylate. Among these compounds, at least one selected from the group consisting of methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, and t-butyl methacrylate is preferably contained, and at least one selected from the group consisting of methyl acrylate, ethyl acrylate, n-butyl acrylate, t-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, and t-butyl methacrylate is particularly preferably contained from a viewpoint of an excellent yield of the composite polymer particle and excellent physical properties of a lithium-ion secondary battery. Further, the (meth)acrylate compound may be used singly or in combination of two or more kinds thereof at any ratio.
[0053] The ratio of the (meth)acrylate compound contained in the polymer constituting the shell portion is preferably 40% by weight or more, more preferably 50% by weight or more, particularly preferably 60% by weight or more, preferably 95% by weight or less, more preferably 90% by weight or less, and particularly preferably 85% by weight or less. By setting the ratio of the (meth)acrylate compound to the lower limit value or more in the above range, a binding property between the composite polymer particle and an active material or a current collector can be further improved. By setting the ratio of the (meth)acrylate compound to the upper limit value or less, a binder composition having excellent stability can be obtained.
[0054] (Monomer Copolymerizable with (Meth)Acrylate Compound)
[0055] Examples of a monomer copolymerizable with a (meth)acrylate compound include a polyfunctional vinyl compound and a monomer having a hydrophilic group.
[0056] (Polyfunctional Vinyl Compound)
[0057] The polyfunctional vinyl compound means a compound having two or more vinyl groups per molecule. By copolymerizing a polyfunctional vinyl compound with the above-mentioned (meth)acrylate compound, a crosslinked structure or a branched structure is formed. A composite polymer particle obtained has excellent toughness and strength due to such a crosslinked structure or branched structure. A bonding property of the composite polymer particle can be thereby enhanced.
[0058] Examples of the polyfunctional vinyl compound include a bifunctional vinyl compound having two vinyl groups per molecule, such as divinyl benzene, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylates, or diallyl phthalate; a trifunctional vinyl compound having three vinyl groups per molecule, such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, aliphatic tri(meth)acrylate, or trivinyl cyclohexane; a tetrafunctional vinyl compound having four vinyl groups per molecule, such as pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, or aliphatic tetra(meth)acrylate; a pentafunctional vinyl compound having five vinyl groups per molecule, such as dipentaerythritol penta(meth)acrylate or dipentaerythritol hexa(meth)acrylate; and a (meth)acrylate having a polyester skeleton, a urethane skeleton, or a phosphazene skeleton, and having two or more vinyl groups per molecule. Further, the polyfunctional vinyl compound may be used singly or in combination of two or more kinds thereof at any ratio.
[0059] The ratio of the polyfunctional vinyl compound in the (meth)acrylate compound is preferably 0.001 parts by weight or more, more preferably 0.01 parts by weight or more, particularly preferably 0.05 parts by weight or more, preferably 7 parts by weight or less, more preferably 5 parts by weight or less, and particularly preferably 3 parts by weight or less with respect to 100 parts by weight of a monomer. By setting the ratio of the polyfunctional vinyl compound to the lower limit value or more in the above range, a binding property between an electrode active material layer and a current collector can be enhanced.
[0060] (Monomer Having Hydrophilic Group)
[0061] Examples of the monomer having a hydrophilic group include a monomer having a carboxy group (—COOH group), a hydroxy group (—OH group), a sulfonic acid group (—SO 3 H group), a —PO 3 H 2 group, a —PO(OH)(OR) group (R represents a hydrocarbon group), or a lower polyoxyalkylene group as a hydrophilic group.
[0062] Examples of the monomer having a carboxy group as a hydrophilic group include a monocarboxylic acid and a derivative thereof; a dicarboxylic acid and a derivative thereof; and acid anhydrides thereof and derivatives thereof. Examples of the monocarboxylic acid include acrylic acid, methacrylic acid, and crotonic acid. Examples of a derivative of the monocarboxylic acid include 2-ethyl acrylic acid, isocrotonic acid, α-acetoxy acrylic acid, β-trans-aryloxy acrylic acid, α-chloro-β-E-methoxy acrylic acid, and β-diamino acrylic acid. Examples of the dicarboxylic acid include maleic acid, fumaric acid, and itaconic acid. Examples of an anhydride of the dicarboxylic acid include maleic anhydride, acrylic anhydride, methyl maleic anhydride, and dimethyl maleic anhydride. Examples of a derivative of the dicarboxylic acid include a halogenated maleic acid such as chloro maleic acid, dichloro maleic acid, or fluoro maleic acid; and a maleate such as methyl maleate, dimethyl maleate, phenyl maleate, methylallyl maleate, diphenyl maleate, nonyl maleate, decyl maleate, dodecyl maleate, octadecyl maleate, or fluoroalkyl maleate.
[0063] Examples of the monomer having a hydroxy group as a hydrophilic group include an ethylenically unsaturated alcohol such as (meth)allyl alcohol, 3-buten-1-ol, or 5-hexen-1-ol; alkanol esters of an ethylenically unsaturated carboxylic acid such as 2-hydroxy ethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, di-2-hydroxyethyl maleate, di-4-hydroxybutyl maleate, or di-2-hydroxypropyl itaconate; esters of polyalkylene glycol and (meth)acrylic acid represented by formula CH 2 ═CR 1 —COO—(C n H 2n O) m —H (m represents an integer of 2 to 9, n represents an integer of 2 to 4, and R 1 represents a hydrogen atom or a methyl group); mono(meth)acrylates of a dihydroxy ester of a dicarboxylic acid, such as 2-hydroxyethyl-2′-(meth)acryloyloxy phthalate or 2-hydroxyethyl-2′-(meth)acryloyloxy succinate; vinyl ethers such as 2-hydroxyethyl vinyl ether or 2-hydroxypropyl vinyl ether; mono(meth)allyl ethers of alkylene glycol, such as (meth)allyl-2-hydroxyethyl ether, (meth)allyl-2-hydroxypropyl ether, (meth)allyl-3-hydroxypropyl ether, (meth)allyl-2-hydroxybutyl ether, (meth)allyl-3-hydroxybutyl ether, (meth)allyl-4-hydroxybutyl ether, or (meth)allyl-6-hydroxyhexyl ether; polyoxyalkylene glycol (meth)monoallyl ethers such as diethylene glycol mono(meth)allyl ether or dipropylene glycol mono(meth)allyl ether; a mono(meth)allyl ether of a halogen and hydroxy-substituted (poly)alkylene glycol, such as glycerol mono(meth)allyl ether, (meth)allyl-2-chloro-3-hydroxypropyl ether, or (meth)allyl-2-hydroxy-3-chloropropyl ether; a mono (meth)allyl ether of a polyhydric phenol, such as eugenol or iso-eugenol, and a halogen-substituted product thereof; and (meth)allyl thioethers of alkylene glycol, such as (meth)allyl-2-hydroxyethyl thioether or (meth)allyl-2-hydroxy propyl thioether.
[0064] Examples of the monomer having a sulfonic acid group as a hydrophilic group include vinyl sulfonic acid, methyl vinyl sulfonic acid, (meth)allyl sulfonic acid, styrene sulfonic acid, (meth)acrylic acid-2-ethyl sulfonate, 2-acrylamido-2-methylpropane sulfonic acid, and 3-allyloxy-2-hydroxypropane sulfonic acid.
[0065] Examples of the monomer having a —PO 3 H 2 group or a —PO(OH)(OR) group (R represents a hydrocarbon group) as a hydrophilic group include phosphoric acid-2-(meth)acryloyloxy ethyl, methyl phosphate-2-(meth)acryloyloxyethyl, and ethyl phosphate-(meth)acryloyloxyethyl.
[0066] Examples of the monomer having a lower polyoxyalkylene group as a hydrophilic group include a poly(alkylene oxide) such as poly(ethylene oxide).
[0067] The ratio of the monomer having a hydrophilic group in the shell portion is preferably 2% by weight or more, more preferably 3% by weight or more, particularly preferably 5% by weight or more, preferably 20% by weight or less, more preferably 15% by weight or less, and particularly preferably 10% by weight or less. By setting the ratio of the monomer having a hydrophilic group to the lower limit value or more in the above range, a binding property between the composite polymer particle and an active material or a current collector can be further improved. In addition, a binder composition having an excellent lithium ion conductivity can be obtained. By setting the ratio of the monomer having a hydrophilic group to the upper limit value or less, a particle stability of the composite polymer particle during polymerization can be excellent.
[0068] (Other Monomers)
[0069] Examples of the monomer copolymerizable with a (meth)acrylate compound further include, in addition to the above polyfunctional vinyl compound and the monomer having a hydrophilic group, a styrene monomer such as styrene, vinyl toluene, t-butyl styrene, vinyl benzoate, methyl vinyl benzoate, vinyl naphthalene, hydroxymethyl styrene, α-methyl styrene, or divinylbenzene; an amide monomer such as acrylamide or methacrylamide; an α,β-unsaturated nitrile compound such as acrylonitrile or methacrylonitrile, olefins such as ethylene or propylene; a diene monomer such as butadiene or isoprene; a halogen atom-containing monomer such as vinyl chloride or vinylidene chloride; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, or vinyl benzoate; vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, or butyl vinyl ether; vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, butyl vinyl ketone, hexyl vinyl ketone, or isopropenyl vinyl ketone; and a heterocyclic ring-containing vinyl compound such as N-vinyl pyrrolidone, vinyl pyridine, or vinyl imidazole. Further, these compounds may be used singly or in combination of two or more kinds thereof at any ratio.
[0070] (Manufacturing Composite Polymer Particle Having Core-Shell Structure)
[0071] When a composite polymer particle having a core-shell structure in which a shell portion containing a polymer having a binding property is formed on a surface of the composite polymer particle is used as the composite polymer particle, the composite polymer particle is obtained by polymerizing a mixture of two or more kinds of monomers in stages. A method for manufacturing such a composite polymer particle is disclosed at pages 38 to 45 of Polymer Latex (New Polymer Bunko 26) (Polymer Publishing Society, first edition), JP 4473967 B2, or the like.
[0072] Specifically, the composite polymer particle having a core-shell structure is manufactured in the following manner: a monomer that provides a first stage polymer is polymerized to obtain a composite polymer particle (seed particle) as a core portion, and a monomer that provides a polymer having a binding property as the second stage is polymerized in the presence of the composite polymer particle (seed particle) as a core portion. In this case, a core-shell structure may be formed by polymerizing a composite polymer particle (seed particle) as a core portion, then adding and porimerizing a monomer that provides a polymer having a binding property for a shell portion thereto in the same reactor, or a core-shell structure may be formed by polymerizing a monomer for forming a shell portion in a reactor using a seed particle as a core portion which has been formed in another reactor.
[0073] Note that, the composite polymer particle used as a seed particle can be obtained by polymerizing a monomer solution containing a polymer (preferably, a solution polymerization polymer) in an aqueous medium, and the composite polymer particle used as a seed particle can be manufactured as described in the section of (Method for manufacturing composite polymer particle).
[0074] (Binder Composition)
[0075] The binder composition of the present invention contains a solvent in addition to the composite polymer particle described above. Usually, in the binder composition, the composite polymer particle is dispersed in a solvent, and the binder composition is a fluid-like composition. As the solvent used in the binder composition, usually, a solvent similar to the aqueous medium used in manufacturing the composite polymer particle can be used. Among the solvents, water is preferably used. Further, the solvents may be used singly or in combination of two or more kinds thereof at any ratio.
[0076] The amount of a solvent in the binder composition is such an amount that a concentration of a solid content in the binder composition is usually 15% by weight or more, preferably 20% by weight or more, more preferably 30% by weight or more, usually 70% by weight or less, preferably 65% by weight or less, and more preferably 60% by weight or less from a viewpoint of excellent workability in manufacturing a slurry composition for forming an electrode active material layer. Here, the solid content in the binder composition means a component which is not evaporated but remains when the binder composition is dried and a liquid is removed.
[0077] (Lithium-Ion Secondary Battery)
[0078] The binder composition of the present invention can be used for a lithium-ion secondary battery electrode. The lithium-ion secondary battery electrode is obtained by forming an electrode active material layer on a current collector. The electrode active material layer contains an electrode active material, the binder composition of the present invention, and a thickening agent, a conductive material, and the like optionally used. Further, the content of the binder composition in the electrode active material layer is from 0.1 to 20 parts by weight, preferably from 0.2 to 15 parts by weight, and more preferably from 0.3 to 10 parts by weight with respect to 100 parts by weight of the electrode active material layer.
[0079] The electrode active material layer is formed by applying a slurry composition containing an electrode active material, the binder composition of the present invention, and a thickening agent, a conductive material, and the like optionally used onto a current collector, and drying the slurry composition.
[0080] A method for applying a slurry composition onto a current collector is not particularly limited. Examples of the method include a doctor blade method, a dip method, a reverse roll method, a direct roll method, a gravure method, an extrusion method, comma direct coating, slide die coating, and a brush coating method. Examples of a drying method include drying with warm air, hot air, or low humidity air, vacuum drying, and a drying method by irradiation with a (far)infrared ray, an electron beam, or the like. Drying time is usually from 1 to 60 minutes. A drying temperature is usually from 40 to 180° C. An electrode active material layer may be formed by repeating applying and drying a slurry composition a plurality of times.
[0081] Here, the slurry composition can be obtained by mixing an electrode active material, a binder, a thickening agent and a conductive material optionally used, a solvent such as water, and the like.
[0082] A mixing method in preparing a slurry composition is not particularly limited. However, examples thereof include a method using a mixing apparatus such as a stirring type, a shaking type, or a rotary type. Examples thereof further include a method using a dispersion kneading apparatus such as a homogenizer, a ball mill, a sand mill, a roll mill, a planetary mixer, or a planetary kneader.
[0083] (Current Collector)
[0084] Examples of a material of the current collector include metal, carbon, and a conductive polymer. Metal is preferably used. Examples of the metal for the current collector include aluminum, platinum, nickel, tantalum, titanium, stainless steel, copper, and an alloy. Among these metals, copper, aluminum, or an aluminum alloy is preferably used in view of conductivity and voltage resistance.
[0085] The thickness of the current collector is preferably from 5 to 100 μm, more preferably from 8 to 70 μm, and still more preferably from 10 to 50 μm.
[0086] (Electrode Active Material)
[0087] When a lithium-ion secondary battery electrode is a positive electrode, examples of an electrode active material (positive electrode active material) include a metal oxide which can be doped or de-doped with a lithium ion reversibly. Examples of such a metal oxide include lithium cobaltate, lithium nickelate, lithium manganate, and lithium iron phosphate. Note that, the positive electrode active material exemplified in the above may be appropriately used singly or in combination of a plurality of kinds thereof according to an intended use.
[0088] Examples of an active material of a negative electrode (negative electrode active material) as a counter electrode of a positive electrode in a lithium-ion secondary battery include easily graphitizable carbon, hardly graphitizable carbon, low-crystalline carbon (amorphous carbon) such as pyrolytic carbon, graphite (natural graphite, artificial graphite), an alloy material formed of tin or silicon, and an oxide such as silicon oxide, tin oxide, or lithium titanate. Note that, the negative electrode active material exemplified in the above may be appropriately used singly or in combination of a plurality of kinds thereof according to an intended use.
[0089] The shape of the electrode active material in a lithium-ion secondary battery electrode is preferably adjusted into a granular shape. When the shape of a particle is granular, an electrode having a higher density can be formed in forming the electrode.
[0090] The volume average particle diameter of the electrode active material in a lithium-ion secondary battery electrode is usually from 0.1 to 100 μm, preferably from 0.5 to 50 μm, and more preferably from 0.8 to 30 μm in each of a positive electrode and a negative electrode.
[0091] (Conductive Material)
[0092] The electrode active material layer may contain a conductive material, as necessary. The conductive material is not particularly limited as long as having conductivity, but a particulate material having conductivity is preferable. Examples thereof include conductive carbon black such as furnace black, acetylene black, or Ketjen black; graphite such as natural graphite or artificial graphite; and a carbon fiber such as a polyacrylonitrile carbon fiber, a pitch carbon fiber, or a vapor grown carbon fiber. When the conductive material is a particulate material, the average particle diameter thereof is not particularly limited, but is preferably smaller than that of the electrode active material, and is preferably from 0.001 to 10 μm, more preferably from 0.05 to 5 μm, and still more preferably from 0.1 to 1 μm from a viewpoint of exhibiting a sufficient conductivity with a smaller use amount.
[0093] (Thickening Agent)
[0094] The electrode active material layer may contain a thickening agent, as necessary. Examples of the thickening agent include a cellulose polymer such as carboxymethylcellulose, methylcellulose, or hydroxypropylcellulose, and an ammonium salt or an alkali metal salt thereof; (modified) poly(meth)acrylic acid and an ammonium salt or an alkali metal salt thereof; polyvinyl alcohols such as (modified) polyvinyl alcohol, a copolymer of acrylic acid or acrylate and vinyl alcohol, or a copolymer of maleic anhydride, maleic acid, or fumaric acid and vinyl alcohol; polyethylene glycol, polyethyleneoxide, polyvinyl pyrrolidone, modified polyacrylic acid, oxidized starch, starch phosphate, casein, various modified starch, and an acrylonitrile-butadiene copolymer hydrogenated product. Among these compounds, carboxymethylcellulose, an ammonium salt thereof, and an alkali metal salt thereof are preferably used. Note that, in the present invention, “(modified) poly” means “non-modified poly” or “modified poly”.
[0095] The content of the thickening agent in the electrode active material layer is preferably within a range not having an influence on a battery characteristic, and is preferably from 0.1 to 5 parts by weight, more preferably from 0.2 to 4 parts by weight, and still more preferably from 0.3 to 3 parts by weight with respect to 100 parts by weight of the electrode active material layer.
[0096] (Lithium-Ion Secondary Battery)
[0097] A lithium-ion secondary battery can be manufactured using a lithium-ion secondary battery electrode containing the binder composition of the present invention. For example, the lithium-ion secondary battery uses a lithium-ion secondary battery electrode in which an electrode active material layer containing the binder composition of the present invention is formed as at least one of a positive electrode and a negative electrode, and further contains a separator and an electrolytic solution.
[0098] Examples of the separator include a microporous film or a nonwoven fabric containing a polyolefin resin such as polyethylene or polypropylene, or an aromatic polyamide resin; and a porous resin coating containing inorganic ceramic powder.
[0099] The thickness of the separator is preferably from 0.5 to 40 μm, more preferably from 1 to 30 μm, and still more preferably from 1 to 25 μm from a viewpoint of reducing a resistance due to the separator in a lithium-ion secondary battery and excellent workability in manufacturing the lithium-ion secondary battery.
[0100] (Electrolytic Solution)
[0101] The electrolytic solution is not particularly limited, but examples thereof include a solution obtained by dissolving a lithium salt as a supporting electrolyte in a non-aqueous solvent. Examples of the lithium salt include LiPF 6 , LiAsF 6 , LiBF 4 , LiSbF 6 , LiAlCl 4 , LiClO 4 , CF 3 SO 3 Li, C 4 F 9 SO 3 Li, CF 3 COOLi, (CF 3 CO) 2 NLi, (CF 3 SO 2 ) 2 NLi, and (C 2 F 5 SO 2 )NLi. LiPF 6 , LiClO 4 , and CF 3 SO 3 Li which are easily dissolved in a solvent and exhibit a high dissociation degree are preferably used. These compounds can be used singly or in mixture of two or more kinds thereof. The amount of the supporting electrolyte is usually 1% by weight or more, preferably 5% by weight or more, usually 30% by weight or less, and preferably 20% by weight or less with respect to the electrolytic solution. When the amount of the supporting electrolyte is either too large or too small, an ion conductivity decreases, and leading to deterioration of charging characteristic and discharge characteristic of a battery.
[0102] A solvent used for the electrolytic solution is not particularly limited as long as dissolving a supporting electrolyte, but examples thereof usually include alkyl carbonates such as dimethyl carbonate (DMC), ethylene carbonate (EC), diethyl carbonate (DEC), propylene carbonate (PC), butylene carbonate (BC), or methylethyl carbonate (MEC); esters such as γ-butyrolactone or methyl formate; ethers such as 1,2-dimethoxy ethane or tetrahydrofuran; and sulfur-containing compounds such as sulfolane or dimethyl sulfoxide. Dimethyl carbonate, ethylene carbonate, propylene carbonate, diethyl carbonate, and methylethyl carbonate are preferable because a particularly high ion conductivity is easily obtained and a temperature range to be used is wide. These compounds can be used singly or in mixture of two or more kinds thereof. Further, the electrolytic solution can contain an additive. In addition, a carbonate compound such as vinylene carbonate (VC) is preferable as the additive.
[0103] Examples of an electrolytic solution other than the above compounds include a gel-like polymer electrolyte in which a polymer electrolyte such as polyethylene oxide or polyacrylonitrile is impregnated with an electrolytic solution, and an inorganic solid electrolyte such as lithium sulfide, LiI, Li 3 N, or Li 2 S—P 2 S 5 glass ceramic.
[0104] A lithium-ion secondary battery is obtained by overlaying a negative electrode and a positive electrode with a separator interposed therebetween, winding or folding the resulting product according to a battery shape, putting the resulting product in a battery container, injecting an electrolytic solution into the battery container, and sealing an opening of the battery container. An overcurrent prevention device such as an expand metal, a fuse, or a PTC device, a lead plate, or the like is further put therein as necessary to prevent an increase in pressure in the battery, overcharge and overdischarge. The shape of the battery may be a laminate cell type, a coin type, a button type, a sheet type, a cylinder type, a square type, a flat type, or the like.
[0105] A lithium-ion secondary battery using the binder composition of the present invention can lower charge/discharge performance in cases when the battery abnormally generates heat or is in an abnormally high-temperature environment.
EXAMPLES
[0106] Hereinafter, the present invention will be described specifically by showing Examples. However, the present invention is not limited to the following Examples, but can be performed by modification in a range not departing from the abstract of the present invention and a scope equal thereto. Note that, “%” and “part” indicating the amount in the following description are based on the weight unless otherwise specified. In addition, operations described below were performed at a normal temperature and a normal pressure unless otherwise specified.
[0107] In Examples and Comparative Examples, evaluation for a binding property and temperature dependency of a resistance value was performed as follows.
[0108] (Binding Property)
[0109] An electrode manufactured in each of Examples and Comparative Examples was cut out into a rectangular shape having a length of 100 mm and a width of 10 mm to be used as a test piece. A cellophane tape was pasted on a surface of an electrode active material layer with the surface of the electrode active material layer facing downward. In this case, a cellophane tape defined in JIS 21522 was used. In addition, the cellophane tape was fixed to a horizontal test stand with an adhesive surface facing upward. Thereafter, one end of a current collector was pulled vertically upward at a pulling rate of 50 mm/min and the cellophane tape was peeled off. A stress at this time was measured. This measurement was performed three times, and an average value of stresses measured was determined to be used as a peel strength.
[0110] The peel strength determined was judged based on the following criteria. A larger peel strength indicates a larger binding force of the electrode active material layer on the current collector, that is, indicates an excellent binding property.
[0000] A: 4 N/m or more
B: 3 N/m or more and less than 4 N/m
C: 2 N/m or more and less than 3 N/m
D: less than 2 N/m
[0111] (Temperature Dependency of Resistance Value)
[0112] An electrode manufactured in each of Examples and Comparative Examples was cut out into a test piece having a size of 50 mm×40 mm. This test piece was sandwiched by SUS plates having a thickness of 0.2 mm, was put in a thermostatic bath while a load of 200 g was applied to the test piece, and was held at a predetermined temperature (50° C., 60° C., 70° C., 80° C., 90° C., or 100° C.) for ten minutes. Thereafter, a resistance value was measured. Table 1 indicates resistance values at temperatures when a measured value at 80° C. is assumed to be 100. A test piece increasing a resistance value at 90° C. or higher has an excellent characteristic against an abnormal temperature.
Example 1
[0113] (Manufacturing Binder Composition)
[0114] 100 parts of a monomer solution obtained by dissolving 20 parts of SEBS (manufactured by Asahi Kasei Chemicals Corporation, Tuftec “H1041” (having an inflection point of an elastic modulus around 80° C.)) in 80 parts of styrene beforehand, 4 parts of sodium lauryl sulfate as an emulsifier, 150 parts of ion-exchanged water as a solvent, and 0.5 parts of ammonium persulfate as a polymerization initiator were put in a 5 MPa pressure-resistant container equipped with a stirrer. The resulting mixture was sufficiently stirred. Thereafter, the temperature thereof was raised to 80° C., and polymerization at the first stage was started.
[0115] When the polymerization conversion rate reached 96%, 50 parts of n-butyl acrylate (hereinafter, also referred to as “BA”) and 1 part of a polymerization initiator were prop-added, and polymerization at the second stage was performed. When the total polymerization conversion rate reached 98%, the mixture was cooled, and the reaction was stopped to obtain a mixture containing a composite polymer particle. A 5% aqueous sodium hydroxide solution was added to this mixture, and the pH thereof was adjusted to 7 to obtain a binder composition containing a desired composite polymer particle.
[0116] (Manufacturing Slurry Composition)
[0117] 99 parts of natural graphite as a negative electrode active material formed of carbon, 1 part of the binder composition in terms of a solid content, and 1 part of a high molecular weight type carboxymethyl cellulose (1% aqueous solution of “MAC800LC” manufactured by NIPPON PAPER Chemicals Co., Ltd., viscosity measured with a B-type viscometer at 25° C.: 7800 mPa·s) in terms of a solid content as a thickening agent were put in a planetary mixer. Ion-exchanged water was further added thereto such that the total concentration of the solid content was 52%, and was mixed therewith to prepare a slurry composition.
[0118] (Manufacturing Electrode)
[0119] The slurry composition was applied onto a copper foil having a thickness of 20 μm as a current collector with a comma coater. At this time, the slurry composition was applied such that the solid content of the slurry composition per unit area of a surface of the copper foil was 11 mg/cm 2 to 12 mg/cm 2 . Thereafter, the slurry composition applied was dried to form an electrode active material layer on a surface of the copper foil. Drying was performed by conveying the copper foil in an oven at 60° C. at a rate of 0.5 m/min over two minutes.
[0120] Thereafter, the copper foil was subjected to a heat treatment at 120° C. for two minutes to obtain a negative electrode raw material. This raw material was pressed with a roll press machine such that the density of a negative electrode active material layer in a negative electrode was 1.50 g/cm 3 to 1.60 g/cm 3 to obtain a negative electrode. A part of this negative electrode was cut out, and a resistance value and a binding property of the negative electrode were measured.
Example 2
[0121] (Manufacturing Binder Composition)
[0122] 105 parts of a monomer solution obtained by dissolving 25 parts of SEBS (manufactured by Kraton Corporation, Kraton G1657MS (having a large linear expansion coefficient in a range of 50° C. to 150° C.)) in 80 parts of styrene beforehand, 4 parts of sodium lauryl sulfate as an emulsifier, 150 parts of ion-exchanged water as a solvent, and 0.5 parts of ammonium persulfate as a polymerization initiator were put in a 5 MPa pressure-resistant container equipped with a stirrer. The resulting mixture was sufficiently stirred. Thereafter, the temperature thereof was raised to 80° C., and polymerization at the first stage was started.
[0123] When the polymerization conversion rate reached 96%, 30 parts of n-butyl acrylate, 5 parts of methyl acrylate (hereinafter, also referred to as “MA”), and 1 part of a polymerization initiator were prop-added, and polymerization at the second stage was performed. When the total polymerization conversion rate reached 98%, the mixture was cooled, and the reaction was stopped to obtain a mixture containing a composite polymer particle. A 5% aqueous sodium hydroxide solution was added to this mixture, and the pH thereof was adjusted to 7 to obtain a binder composition containing a desired composite polymer particle.
[0124] A slurry composition and an electrode were manufactured in a similar manner to Example 1 except that the binder composition obtained in this way was used.
Example 3
[0125] (Manufacturing Binder Composition)
[0126] 100 parts of a monomer solution obtained by dissolving 30 parts of SEBS (manufactured by Asahi Kasei Chemicals Corporation, Tuftec “H1041”) in 70 parts of styrene beforehand, 4 parts of sodium lauryl sulfate as an emulsifier, 150 parts of ion-exchanged water as a solvent, and 0.5 parts of ammonium persulfate as a polymerization initiator were put in a 5 MPa pressure-resistant container equipped with a stirrer. The resulting mixture was sufficiently stirred. Thereafter, the temperature thereof was raised to 80° C., and polymerization at the first stage was started.
[0127] When the polymerization conversion rate reached 96%, 100 parts of n-butyl acrylate, 2 parts of methyl acrylate, and 1 part of a polymerization initiator were prop-added, and polymerization at the second stage was performed. When the total polymerization conversion rate reached 98%, the mixture was cooled, and the reaction was stopped to obtain a mixture containing a composite polymer particle. A 5% aqueous sodium hydroxide solution was added to this mixture, and the pH thereof was adjusted to 7 to obtain a binder composition containing a desired composite polymer particle.
[0128] A slurry composition and an electrode were manufactured in a similar manner to Example 1 except that the binder composition obtained in this way was used.
Comparative Example 1
[0129] (Manufacturing Binder Composition)
[0130] 100 parts of styrene, 4 parts of sodium lauryl sulfate as an emulsifier, 150 parts of ion-exchanged water as a solvent, and 0.5 parts of ammonium persulfate as a polymerization initiator were put in a 5 MPa pressure-resistant container equipped with a stirrer. The resulting mixture was sufficiently stirred. Thereafter, the temperature thereof was raised to 80° C., and polymerization at the first stage was started.
[0131] When the polymerization conversion rate reached 96%, 50 parts of n-butyl acrylate and 1 part of a polymerization initiator were prop-added, and polymerization at the second stage was performed. When the total polymerization conversion rate reached 98%, the mixture was cooled, and the reaction was stopped to obtain a mixture containing a composite polymer particle. A 5% aqueous sodium hydroxide solution was added to this mixture, and the pH thereof was adjusted to 7 to obtain a binder composition containing a desired composite polymer particle.
[0132] A slurry composition and an electrode were manufactured in a similar manner to Example 1 except that the binder composition obtained in this way was used.
Comparative Example 2
[0133] (Manufacturing Binder Composition)
[0134] 50 parts of styrene, 4 parts of sodium lauryl sulfate as an emulsifier, 150 parts of ion-exchanged water as a solvent, and 0.5 parts of ammonium persulfate as a polymerization initiator were put in a 5 MPa pressure-resistant container equipped with a stirrer. The resulting mixture was sufficiently stirred. Thereafter, the temperature thereof was raised to 80° C., and polymerization at the first stage was started.
[0135] When the polymerization conversion rate reached 96%, 100 parts of n-butyl acrylate and 1 part of a polymerization initiator were prop-added, and polymerization at the second stage was performed. When the total polymerization conversion rate reached 98%, the mixture was cooled, and the reaction was stopped to obtain a mixture containing a composite polymer particle. A 5% aqueous sodium hydroxide solution was added to this mixture, and the pH thereof was adjusted to 7 to obtain a binder composition containing a desired composite polymer particle.
[0136] A slurry composition and an electrode were manufactured in a similar manner to Example 1 except that the binder composition obtained in this way was used.
[0000]
TABLE 1
Ex. 1
Ex. 2
Ex. 3
Comp. Ex. 1
Comp. Ex. 2
Polymerization at
Polymer
SEBS,
20
25
30
—
—
the first stage
composition
Amount
(part)
Monomer
Styrene,
80
80
70
100
50
composition
Amount
(part)
Polymerization at
Monomer
BA,
50
30
100
50
100
the second stage
composition
Amount
(part)
MA,
—
5
2
—
—
Amount
(part)
Binding property
B
A
A
D
A
Evaluation item
Temperature
50° C.
130
118
124
120
136
dependency of
60° C.
125
108
115
112
124
resistance
70° C.
112
103
108
103
112
value (based
80° C.
100
100
100
100
100
on 80° C.)
90° C.
186
165
154
92
92
100° C.
176
170
142
90
84
[0137] As indicated in Table 1, an electrode manufactured using a binder composition for a lithium-ion secondary battery electrode, containing a composite polymer particle obtained by polymerizing a monomer solution containing a polymer in an aqueous medium has an excellent binding property and an excellent resistance value. | The present invention relates to a binder composition for lithium-ion secondary battery electrodes. Recently, there is a need for a lithium-ion secondary battery which has the excellent property of accommodating an abnormal situation so that in cases when the battery has heated up abnormally or is in an abnormally high-temperature environment, the battery can lower the charge/discharge performance thereof. The present invention solves the above-mentioned problem by using, as a binder for electrodes, composite polymer particles obtained by polymerizing, in an aqueous medium, a monomer solution containing a polymer. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to German Patent Application No. 102015016544.5, filed Dec. 18, 2015, which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention pertains to a method for determining an evasive trajectory, on which a vehicle can drive around an obstacle, as well as means for implementing this method.
BACKGROUND
[0003] A method and a device for avoiding collisions of a vehicle with an obstacle are known from EP 2 141 057 A1. This document proposes to predict the trajectory of the vehicle based on measuring signals of various sensors and to deliver collision avoidance control information to a brake control unit and a steering control unit in case the predicted trajectory exceedingly approaches the obstacle. However, it remains unclear how the collision avoidance control information is structured and how it can be processed in the brake control unit and the steering control unit in order to actually avoid an impending collision.
SUMMARY
[0004] An objective of the present invention can be seen in developing a method that actually makes it possible to avoid a collision with a detected obstacle.
[0005] According to an embodiment of the invention, this objective is attained with a method for determining an evasive trajectory, on which a vehicle can drive around an obstacle on a roadway, wherein a) a component of a candidate trajectory extending parallel to the roadway is defined by selecting weighting coefficients of a first weighted sum of orthogonal functions of the time, b) a component of the candidate trajectory extending perpendicular to the roadway is defined by selecting weighting coefficients of a second weighted sum of the orthogonal functions, c) an optimization parameter for the candidate trajectory is calculated, and d) at least one coefficient of at least one of the sums is varied and step c) is repeated if the optimization parameter does not reach a stop criterion.
[0006] The time until an expected collision on the candidate trajectory occurs may particularly serve as optimization parameter.
[0007] In this case, the stop criterion is preferably defined in that this time is longer than the time required for traveling the candidate trajectory.
[0008] It is also conceivable that a candidate trajectory is only considered as an evasive trajectory if it fulfills one or more of the following boundary conditions: compliance with an upper limit of the acceleration of the vehicle in order to take into account the fact that the acceleration of the vehicle is regardless in which direction limited by the coefficient of friction between tires and roadway, compliance with a lower limit of the distance of the vehicle from the obstacle because the collision avoidance fails in any case if this distance becomes 0, or disappearance of the speed component of the vehicle extending orthogonal to the roadway at the end of the evasive trajectory. If it is not possible to determine an evasive trajectory that fulfills this condition, it may in fact be possible to drive around the obstacle, but the vehicle is subsequently carried off the roadway due to its non-disappearing transversal speed.
[0009] This boundary condition can be taken into account in different ways. The compliance with the upper limit of the acceleration can be checked, in particular, by calculating a scalar cost function for each candidate trajectory.
[0010] With respect to other boundary conditions, particularly those concerning the end of the evasive trajectory, it is possible to select the value for at least one coefficient, which fulfills the boundary condition together with previously selected values of other coefficients, beforehand in step a) or b) such that trajectories, which cannot be considered as evasive trajectories anyway because they do not fulfill the boundary conditions, are not even selected and analyzed as candidate trajectories in the first place.
[0011] In order to systematically search for a favorable evasive trajectory, it is advantageous if the candidate trajectories can be parameterized. This is achieved with the aid of weighting coefficients; they reduce the problem of determining an ideal or at least approximately ideal evasive trajectory to determining a point in a multidimensional vector space, wherein the number of dimensions of the vector space corresponds to the number of weighting coefficients of the parallel and the orthogonal component.
[0012] The parallel and the orthogonal component may respectively be polynomials. Trigonometric and algebraic polynomials may particularly be considered, i.e. the orthogonal functions are the functions of the form:
[0000]
e
i
2
π
mkt
/
T
-
e
-
i
2
π
mkt
/
T
2
i
e
i
2
π
mkt
/
T
+
e
-
i
2
π
mkt
/
T
2
i
[0000] the period T of which corresponds to the duration of the evasive trajectory and in which k has integral values between 0 and n or in which the power of functions have integral exponents. The algebraic polynomials—which are also referred to as polynomial functions—are preferred due to their simple computability.
[0013] In order to accelerate the determination of a suitable evasive trajectory, it is desirable to sensibly define as many of the weighting coefficients as possible beforehand such that they do not have to be optimized iteratively. Since the current coordinate values of the vehicle parallel and orthogonal to the roadway are known (or can be assumed to be zero), at least one of these coordinate values can be predefined as coefficient of a zero order term of at least one of the polynomials.
[0014] If the polynomials are algebraic polynomials, the first time derivative of the current coordinate value of the vehicle parallel or orthogonal to the roadway may furthermore be predefined as coefficient of a first order term of at least one of the polynomials; in other words: the current speed of the vehicle parallel to the roadway—which is usually available in the form of a speedometer signal—and the current speed perpendicular to the roadway—which is calculated thereof, if applicable, based on the steering wheel angle or the like—are used as coefficients of first order terms.
[0015] In addition, the second time derivative of the coordinate value of the vehicle parallel or orthogonal to the roadway—i.e. the directly measured acceleration of the vehicle or the acceleration calculated based on the known speed—may be predefined as coefficient of a second order term of at least one of the polynomials.
[0016] In this way, the dimensions of the optimization problem can be reduced to 6 beforehand. The computing effort required until a usable evasive trajectory is determined or its existence can be negated with sufficient certainty can thereby be significantly reduced.
[0017] The higher the order of the polynomials, the more accurately an arbitrary evasive trajectory can be approximated by means of the polynomials and the higher the certainty that a suitable evasive trajectory can also be found if it actually exists. This is the reason why each polynomial should comprise at least two terms, the coefficients of which are varied in step c).
[0018] On the other hand, no more than four terms of each polynomial should be varied in step c) in order to limit the computing effort.
[0019] Another objective of the invention can be seen in disclosing a driver assistance system for a motor vehicle that is able to quickly and reliably determine a suitable evasive trajectory in a hazardous situation.
[0020] According to an embodiment of the invention, this objective is attained with a driver assistance system for a motor vehicle that features a proximity sensor and a computer unit that is connected to the proximity sensor in order to carry out the above-described method when the proximity sensor detects an obstacle in the surroundings of the vehicle.
[0021] The computer unit may be connected to at least a steering system of the vehicle in order to steer the vehicle around the obstacle along the evasive trajectory. In order to realize a potentially required acceleration and/or deceleration of the vehicle along the evasive trajectory, the computer unit should preferably also be connected to an engine control and/or brake control.
[0022] The invention furthermore pertains to a computer program product comprising instructions that, when the computer program product is executed on a computer, enable this computer to carry out the above-described method or to operate as a computer unit in a driver assistance system in the above-described fashion, to a machine-readable data carrier, on which such instructions are recorded, as well as to a computer unit for a driver assistance system with a) means for defining a component of a candidate trajectory extending parallel to the roadway by selecting weighting coefficients of a first weighted sum of orthogonal functions; b) means for defining a component of the candidate trajectory extending orthogonal to the roadway by selecting weighting coefficients of a second weighted sum of the orthogonal functions; c) means for calculating an optimization parameter for the candidate trajectory and d) means for varying coefficients of at least one of the sums and reactivating the means c) if the optimization parameter does not reach a stop criterion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Other characteristics and advantages of the invention can be gathered from the following description of exemplary embodiments with reference to the attached figures. In these figures,
[0024] FIG. 1 shows a typical traffic situation, in which the driver assistance system can be used;
[0025] FIG. 2 shows a block diagram of the driver assistance system; and
[0026] FIG. 3 shows a flow chart of an operating method of the driver assistance system.
DETAILED DESCRIPTION
[0027] The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description
[0028] FIG. 1 shows a motor vehicle 1 that is equipped with the inventive driver assistance system and travels along a roadway 2 , in this case a two-lane road. A vehicle parked on the roadside blocks part of one traffic lane 4 of the roadway 2 , along which the motor vehicle 1 travels, and therefore represents an obstacle 3 that has to be avoided by the motor vehicle 1 in order to prevent a collision.
[0029] Another vehicle 5 travels in an oncoming traffic lane 6 of the roadway 2 . However, an evasive maneuver of the motor vehicle 1 in the direction of the oncoming traffic lane 6 in order to avoid the obstacle 3 cannot provoke a collision with the vehicle 5 .
[0030] FIG. 2 shows a block diagram of the driver assistance system 7 , with which the motor vehicle 1 is equipped. The driver assistance system 7 comprises a speedometer 17 and a proximity sensor 8 , in this case a camera that is directed at the roadway 2 located in front of the motor vehicle 1 , in order to detect the course of the roadway 2 , as well as potential obstacles 3 thereon such as the parked vehicle. Alternatively, a radar sensor may also be provided for the obstacle detection.
[0031] A conventional navigation system 9 , which provides data on the course of the currently traveled roadway 2 , may be provided in order to enhance the detection of the course of the road with the aid of the camera 8 .
[0032] A steering wheel sensor 10 may serve for detecting the angle adjusted on the steering wheel of the motor vehicle 1 by the driver and for estimating a trajectory of the motor vehicle 1 resulting thereof; in addition, an acceleration sensor 11 may be provided for detecting longitudinal and lateral accelerations, to which the motor vehicle 1 is subjected along its trajectory.
[0033] A computer unit 12 , typically a microcomputer, is connected to the sensors 8 , 10 , 11 , 17 and the navigation system 9 . A first utility program 13 running on this microcomputer serves for determining a predicted trajectory, on which the motor vehicle 1 will continue to move from its current position illustrated in FIG. 1 . In this context, the term trajectory refers to a curve in a multidimensional space, the coordinates of which include at least the two position coordinates x and y parallel and perpendicular to the roadway 2 , as well as a time coordinate. The determination of the predicted trajectory is based on the data on the previous trajectory of the motor vehicle 1 delivered by the speedometer 17 , the steering wheel sensor 10 and the acceleration sensor 11 , if applicable with consideration of the further course of the roadway 2 , which can be derived from the data of the navigation system 9 and/or the camera 8 .
[0034] If the motor vehicle 1 has in the recent past moved straightforward on the roadway 2 and the further course of the roadway 2 , as far as known, indicates that the roadway 2 continues in a straight line, the utility program 13 determines the straight trajectory identified by the reference symbol 14 in FIG. 1 as the predicted trajectory in step Si of the flow chart in FIG. 3 .
[0035] The predicted trajectory 14 can generally be expressed in the form of two respective polynomials for coordinates x parallel to the roadway 2 and coordinates y perpendicular thereto:
[0000] x ( t )= b 0 +b 1 t+b 2 t 2 +b 3 t 3 +b 4 t 4 +b 5 t 5
[0000] y ( t )= c 0 +c 1 t+c 2 t 2 +c 3 t 3 +c 4 t 4 +c 5 t 5
[0000] wherein the initial position (b 0 , c 0 ) can—under the assumption that the coordinate system x, y moves with the vehicle—be set equal to zero without loss of generality, (b 1 , c 1 ) and (b 2 , c 2 ) respectively represent the speed and the acceleration of the motor vehicle 1 at the current time t=0 and the remaining coefficients can be determined by adapting the polynomials to positions or speeds of the motor vehicle, which were determined at a previous point in time with the aid of the sensors 8 , 10 , 11 , 17 .
[0036] Based on this predicted trajectory 14 and the data of the proximity sensor 8 , the utility program 13 checks if an obstacle 3 exists, with which the motor vehicle 1 could collide while driving along the predicted trajectory 14 (step S 2 ). This check comprises on the one hand an evaluation of the current data of the proximity sensor with respect to the existence of an object other than the vehicle within the surrounding area monitored by the proximity sensor 8 and on the other hand a prediction of the trajectory of the object with the aid of previous data delivered by the proximity sensor 8 .
[0037] The trajectories of the vehicle and the object are respectively predicted over an identical time period T of a few seconds into the future. A collision hazard is affirmed if the distance between the vehicle and the object falls short of a predefined limiting value at any time within this prediction time period, i.e. if the time TTC remaining until a collision occurs is shorter than T based on the predicted trajectories. This limiting value of the distance may be 0, but preferably has a positive value such that a collision hazard is not only affirmed when an actual collision is predicted, but already when a safety clearance between vehicle and object can no longer be maintained.
[0038] If a collision hazard is negated, the method returns to the starting point and once again begins with the determination of the predicted trajectory S 1 after a predefined waiting period Δt.
[0039] In the traffic situation illustrated in FIG. 1 , step S 2 comprises the detection of a collision hazard in the form of the parked vehicle 3 while the vehicle is located at the point 16 . In this case, the method branches out to step S 3 in order to initially define a candidate evasive trajectory. Analogous to the predicted trajectory 14 , the candidate evasive trajectory comprises two polynomials of the form:
[0000] x ( t )= b (0) 0 +b (0) 1 t+b (0) 2 t 2 +b (0) 3 t 3 +b (0) 4 t 4 +b (0) 5 t 5
[0000] x ( t )= c (0) 0 +c (0) 1 t+c (0) 2 t 2 +c (0) 3 t 3 +c (0) 4 t 4 +c (0) 5 t 5
[0040] If the coordinates refer to a fixed vehicle coordinate system, the zero order coefficients b (0) 0 , c (0) 0 are initialized with the value 0 in S 3 .
[0041] The 1 st order coefficient (0) 1 is initialized with the longitudinal speed v x of the vehicle measured by the speedometer 17 in S 4 . The curvature radius r of the current trajectory of the vehicle is calculated based on the steering angle measured by the steering wheel sensor 10 and the current transversal speed v y is calculated from this curvature radius and from the longitudinal speed v x and set as coefficient c (0) 1 .
[0042] The respective accelerations a x , a y in the driving direction and transverse to the driving direction, which are measured by the sensor 11 , may be set as coefficients b (0) 2 , c (0) 2 in step S 5 ; alternatively, they may also be numerically derived from values of the longitudinal and transversal speeds v x , v y , which were obtained at different times.
[0043] An initial value is defined for the remaining coefficients b (0) 3 , b (0) 4 , b (0) 5 , c (0) 3 , c (0) 4 , c (0) 5 in step S 6 ; for the coefficients referred to as freely variable coefficients below, this initial value may, e.g., be permanently predefined or result from a random selection within a predefined finite interval.
[0044] Boundary conditions are taken into account in the selection of the initial values for the coefficients; for example, if one of these boundary conditions specifies that the acceleration in the direction extending parallel to the roadway should be 0 at the end of the evasive maneuver, only two of the coefficients b (0) 3 , b (0) 4 , b (0) 5 are freely variable whereas the third coefficient, preferably b (0) 5 , is calculated in dependence on the two other coefficients such that the boundary condition:
[0000] a x (T)={umlaut over ( x )}( T )=2 b (0) 2 T+ 6 b (0) 3 T+ 12 b (0) 4 T 2 +20 b (0) 5 T 3 =0
[0000] is fulfilled.
[0045] Two boundary conditions may have to be fulfilled with respect to the motion transverse to the roadway, namely that the coordinate y(T) transverse to the roadway is 0, i.e. that the vehicle is once again correctly positioned along its original trajectory, and that the transversal speed v y =0 at the end of the evasive maneuver. After one of the coefficients, e.g. c (0) 3 , has been freely selected, both other coefficients c (0) 4 , c (0) 5 may be defined by the boundary conditions in this case.
[0046] A cost function is calculated for the selected coefficients in step S 7 . The cost function contains at least one summand of the form:
[0000]
A
=
max
t
∈
[
0
,
T
]
(
2
b
2
(
i
)
+
6
b
3
(
i
)
t
+
12
b
4
(
i
)
t
2
+
20
b
5
(
i
)
t
3
)
2
+
(
2
c
2
(
i
)
+
6
c
3
(
i
)
t
+
12
c
4
(
i
)
t
2
+
20
c
5
(
i
)
t
3
)
2
[0000] which provides a measure for the maximum acceleration, to which the vehicle is subjected for the duration of the candidate trajectory, namely from t=0 until t=T. If A exceeds a limiting value a max , which is predefined by the coefficient of friction of the wheels on the roadway, the candidate trajectory contains locations, at which the required acceleration of the vehicle exceeds the physically possible acceleration, such that the vehicle cannot follow this candidate trajectory. Such a candidate trajectory is discarded in S 8 .
[0047] If the vehicle is able to follow the candidate trajectory, the time TTC* remaining until a collision occurs is estimated anew in step S 9 based on this candidate trajectory. In this case, it is taken into account that the collision with the vehicle 3 in fact can possibly be avoided on the candidate trajectory, but a potential collision with the vehicle 5 may occur instead. If the time TTC* is longer than T (S 10 ), the collision hazard is assumed to be eliminated and the candidate trajectory is considered to be a suitable evasive trajectory for driving around the obstacles 3 and 5 , wherein the computer unit 12 activates one or more actuators 22 in order to act upon the steering system, the brakes and the engine such that the vehicle follows the evasive trajectory (S 11 ).
[0048] If the time TTC* estimated in S 9 is shorter or exactly as long as the time TTC obtained in step 51 , the method returns to step S 6 in order to define new initial values for the variable coefficients b (0) 3 , b (0) 4 , b (0) 5 , c (0) 3 , c (0) 4 , c (0) 5 .
[0049] However, if the time TTC* estimated in S 9 is longer than the time TTC obtained in step S 1 (S 12 ), it is possible to search for other, better combinations based on the combination of coefficients used in this estimation. This may be realized, e.g., in that one of the freely variable coefficients is respectively selected, as well as increased or decreased by a predefined increment, and the dependently variable coefficients are once again adapted such that the boundary conditions are fulfilled (S 13 ), wherein the coefficient set among the obtained sets of coefficients, which corresponds to a candidate trajectory with accelerations <a max and delivers the highest value of TTC*, is then preserved as new coefficient set b (1) 3 , b (1) 4 , b (1) 5 , c (1) 3 , c (1) 4 , c (1) 5 (S 14 , S 15 ).
[0050] In step S 16 , it is once again checked if the value TTC* (i) (i=1, 2, . . . ) of the preserved candidate trajectory is >T, wherein the vehicle is controlled along the evasive trajectory if this is the case. Otherwise, it is checked in S 17 if TTC* (i) is at least greater than the value TTC* (i-1) , which was obtained in an immediately preceding iteration in step S 14 or, if i=1, in step S 9 .
[0051] If this is the case, the method returns to step S 13 .
[0052] If this is not the case and i has at the same time reached a predefined minimum value, the method replies with the message that no suitable evasive trajectory exists (S 18 ).
[0053] If this is not the case and the minimum value of i has not been reached, the method returns to step S 13 , but reduces the increment used in step S 13 .
[0054] According to an enhancement, it is proposed that, while the vehicle 1 is located at the point 16 at the current time t=0, the computer unit 12 not only analyzes the available candidate trajectories that originate from this point 16 , but also candidate trajectories such as 19 , which originate from a point 18 reached in the future if the car continues to drive along the predicted trajectory 14 . If step S 18 is reached during the analysis of these candidate trajectories, i.e. if no suitable evasive trajectory originating from the point 18 exists, this means that it is no longer possible to wait for an intervention by the driver and that, if an evasive trajectory originating from the point 16 exists, the computer unit 12 has to intervene in order to follow this evasive trajectory and thereby avoid the impending collision.
[0055] Although the preceding detailed description and the drawings concern certain exemplary embodiments of the invention, it goes without saying that they are only intended for elucidating the invention and should not be interpreted as restrictions to the scope of the invention. The described embodiments can be modified in various ways without deviating from the scope of the following claims and their equivalents. The description and the figures particularly also disclose characteristics of the exemplary embodiments that are not mentioned in the claims. Such characteristics may also occur in combinations other than those specifically disclosed herein. The fact that several such characteristics are mentioned together in the same sentence or in a different context therefore does not justify the conclusion that they can only occur in the specifically disclosed combination; instead, it should basically be assumed that individual characteristics of several such characteristics can also be omitted or modified as long as the functionality of the invention is not compromised. | A method for finding an evasive trajectory for avoiding an obstacle for a vehicle on a roadway. A component of a candidate trajectory parallel to the roadway is determined by selecting weighting coefficients of a first weighted sum of orthogonal functions of time. A component of the candidate trajectory orthogonal to the roadway is determined by selecting weighting coefficients of a second weighted sum of the orthogonal functions. An optimization parameter for the candidate trajectory is calculated. At least one coefficient of at least one of the sums is modified and the procedure is repeated when the optimization parameter does not reach a termination criterion. | 1 |
FIELD OF THE INVENTION
[0001] The present invention provides novel methods for treating various disorders and conditions, with Botulinum toxins. Importantly, the present invention provides methods useful in relieving pain related to muscle activity or contracture and therefore is of advantage in the treatment of, for example, muscle spasm such as Temporomandibular Joint Disease, low back pain, myofascial pain, pain related to spasticity and dystonia, as well as sports injuries, and pain related to contractures in arthritis.
BACKGROUND OF THE INVENTION
[0002] Heretofore, Botulinum toxins, in particular Botulinum toxin type A, has been used in the treatment of a number of neuromuscular disorders and conditions involving muscular spasm; for example, strabismus, blepharospasm, spasmodic torticollis (cervical dystonia), oromandibular dystonia and spasmodic dysphonia (laryngeal dystonia). The toxin binds rapidly and strongly to presynaptic cholinergic nerve terminals and inhibits the exocytosis of acetylcholine by decreasing the frequency of acetylcholine release. This results in local paralysis and hence relaxation of the muscle afflicted by spasm.
[0003] For one example of treating neuromuscular disorders, see U.S. Pat. No. 5,053,005 to Borodic, which suggests treating curvature of the juvenile spine, i.e., scoliosis, with an acetylcholine release inhibitor, preferably Botulinum toxin A.
[0004] For the treatment of strabismus with Botulinum toxin type A, see Elston, J. S. , et al., British Journal of Ophthalmology, 1985, 69, 718-724 and 891-896. For the treatment of blepharospasm with Botulinum toxin type A, see Adenis, J. P. , et al., J. Fr. Ophthalmol., 1990, 13 (5) at pages 259-264. For treating squint, see Elston, J. S. , Eye, 1990, 4(4):VII. For treating spasmodic and oromandibular dystonia torticollis, see Jankovic et al., Neurology, 1987, 37, 616-623.
[0005] Spasmodic dysphonia has been treated with Botulinum toxin type A. See Blitzer et al., Ann. Otol. Rhino. Laryngol, 1985, 94, 591-594. Lingual dystonia was treated with Botulinum toxin type A according to Brin et al., Adv. Neurol. ( 1987) 50, 599-608. Finally, Cohen et al., Neurology ( 1987) 37 (Suppl. 1), 123-4, discloses the treatment of writer's cramp with Botulinum toxin type A.
[0006] The term Botulinum toxin is a generic term embracing the family of toxins produced by the anaerobic bacterium Clostridium botulinum and, to date, seven immunologically distinct neurotoxins have been identified. These have been given the designations A, B, C, D, E, F and G. For further information concerning the properties of the various Botulinum toxins, reference is made to the article by Jankovic and Brin, The New England Journal of Medicine , No. 17, 1990, pp. 1186-1194, and to the review by Charles L. Hatheway in Chapter 1 of the book entitled Botulinum Neurotoxin and Tetanus Toxin , L. L. Simpson, Ed., published by Academic Press Inc. of San Diego, Calif. 1989, the disclosures in which are incorporated herein by reference.
[0007] The neurotoxic component of Botulinum toxin has a molecular weight of about 150 kilodaltons and is thought to comprise a short polypeptide chain of about 50 kD which is considered to be responsible for the toxic properties of the toxin, i.e., by interfering with the exocytosis of acetylcholine, by decreasing the frequency of acetylcholine release, and a larger polypeptide chain of about 100 kD which is believed to be necessary to enable the toxin to bind to the pre-synaptic membrane.
[0008] The “short” and “long” chains are linked together by means of a simple disulfide bridge. (It is noted that certain serotypes of Botulinum toxin, e.g., type E, may exist in the form of a single chain un-nicked protein, as opposed to a dichain. The single chain form is less active but may be converted to the corresponding dichain by nicking with a protease, e.g., trypsin. Both the single and the dichain are useful in the method of the present invention.)
[0009] In general, four physiologic groups of C. botulinum are recognized (I, II, III, IV). The organisms capable of producing a serologically distinct toxin may come from more than one physiological group. For example, Type B and F toxins can be produced by strains from Group I or II. In addition, other strains of clostridial species (C. baratii, type F; C. butyricum , type E; C. novyi , type C 1 or D) have been identified which can produce botulinum neurotoxins.
[0010] Immunotoxin conjugates of ricin and antibodies, which are characterized as having enhanced cytotoxi-city through improving cell surface affinity, are disclosed in European Patent Specification 0 129 434. The inventors note that botulinum toxin may be utilized in place of ricin.
[0011] Botulinum toxin is obtained commercially by establishing and growing cultures of C. botulinum in a fermenter and then harvesting and purifying the fermented mixture in accordance with known techniques.
[0012] Botulinum toxin type A, the toxin type generally utilized in treating neuromuscular conditions, is currently available commercially from several sources; for example, from Porton Products Ltd. UK, under the trade name “DYSPORT,” and from Allergan, Inc., Irvine, Calif., under the trade name BOTOX®.
[0013] It is one object of the invention to provide novel treatments of neuromuscular disorders and conditions with various Botulinum toxin types. It is another object of the present invention to relieve pain with various Botulinum toxin types.
SUMMARY OF THE INVENTION
[0014] The present invention provides a method for relieving pain, associated with muscle contractions, a composition and a method of treating conditions such as cholinergic controlled secretions including excessive sweating, lacrimation and mucus secretions and a method for treating smooth muscle disorders including, but not limited to, spasms in the sphincter of the cardiovascular arteriole, gastrointestinal system, urinary, gall bladder and rectum, which method comprises administering to the patient suffering from said disorder or condition a therapeutically effective amount of Botulinum toxin selected from the group consisting of Botulinum toxin types B, C, D, E, F and G.
[0015] Each serotype of Botulinum toxin has been identified as immunologically different proteins through the use of specific antibodies. For example, if the antibody (antitoxin) recognizes, that is, neutralizes the biological activity of, for example, type A it will not recognize types B,C,D, E, F or G.
[0016] While all of the Botulinum toxins appear to be zinc endopeptidases, the mechanism of action of different serotypes, for example, A and E within the neuron appear to be different than that of Type B. In addition, the neuronal surface “receptor” for the toxin appears to be different for the serotypes.
[0017] In the area of use of the Botulinum toxins in accordance with the present invention with regard to organ systems which involve the release of neurotransmitter, it is expected to introduce the toxins A, B, C, D, E, F, and G directly by local injections.
DETAILED DESCRIPTION
[0018] The Botulinum toxins used according to the present invention are Botulinum toxins type A, B, C, D, E, F and G.
[0019] The physiologic groups of Clostridium botulinum types are listed in Table I.
TABLE I Physiologic Groups of Clostridium botulinum Phenotypically Toxin Glucose Phages Related Sero- Milk Fermen- & Clostridium Group Type Biochemistry Digest tation Lipase Plasmids (nontoxigenic) I A, B, F proteolytic saccharolytic + + + + C. sporogenes II B, E, F nonproteolytic saccharolytic − + + + psychotrophic III C, D nonproteolytic saccharolytic ± + + + C. novyi IV G proteolytic nonsaccharolytic + − − − C. subterminale
[0020] These toxin types may be produced by selection from the appropriate physiologic group of Clostridium botulinum organisms. the organisms designated as Group I are usually referred to as proteolytic and produce Botulinum toxins of types A, B and F. The organisms designated as Group II are saccharolytic and produce Botulinum toxins of types B, E and F. The organisms designated as Group III produce only Botulinum toxin types C and D and are distinguished from organisms of Groups I and II by the production of significant amounts of propionic acid. Group IV organisms only produce neurotoxin of type G. The production of any and all of the Botulinum toxin types A, B, C, D, E, F and G are described in Chapter 1 of Botulinum Neurotoxin and Tetanus Toxin, cited above, and/or the references cited therein. Botulinum toxins types B, C, D, E, F and G are also available from various species of clostridia.
[0021] Currently fourteen species of clostridia are considered pathogenic. Most of the pathogenic strains produce toxins which are responsible for the various pathological signs and symptoms. Organisms which produce Botulinum toxins have been isolated from botulism outbreaks in humans (types A, B, E and F) and animals (types C and D). Their identities were described through the use of specific antitoxins (antibodies) developed against the earlier toxins. Type G toxin was found in soil and has low toxigenicity. However, it has been isolated from autopsy specimens, but thus far there has not been adequate evidence that type G botulism has occurred in humans.
[0022] Preferably, the toxin is administered by means of intramuscular injection directly into a local area such as a spastic muscle, preferably in the region of the neuromuscular junction, although alternative types of administration (e.g., subcutaneous injection), which can deliver the toxin directly to the affected region, may be employed where appropriate. The toxin can be presented as a sterile pyrogen-free aqueous solution or dispersion and as a sterile powder for reconstitution into a sterile solution or dispersion.
[0023] Where desired, tonicity adjusting agents such as sodium chloride, glycerol and various sugars can be added. Stabilizers such as human serum albumin may also be included. The formulation may be preserved by means of a suitable pharmaceutically acceptable preservative such as a paraben, although preferably it is unpreserved.
[0024] It is preferred that the toxin is formulated in unit dosage form; for example, it can be provided as a sterile solution in a vial or as a vial or sachet containing a lyophilized powder for reconstituting a suitable vehicle such as saline for injection.
[0025] In one embodiment, the Botulinum toxin is formulated in a solution containing saline and pasteurized human serum albumin, which stabilizes the toxin and minimizes loss through non-specific adsorption. The solution is sterile filtered (0.2 micron filter), filled into individual vials and then vacuum-dried to give a sterile lyophilized powder. In use, the powder can be reconstituted by the addition of sterile unpreserved normal saline (sodium chloride 0.9% for injection).
[0026] The dose of toxin administered to the patient will depend upon the severity of the condition; e.g., the number of muscle groups requiring treatment, the age and size of the patient and the potency of the toxin. The potency of the toxin is expressed as a multiple of the LD 50 value for the mouse, one unit (U) of toxin being defined as being the equivalent amount of toxin that kills 50% of a group of 18 to 20 female Swiss-Webster mice, weighing about 20 grams each.
[0027] The dosages used in human therapeutic applications are roughly proportional to the mass of muscle being injected. Typically, the dose administered to the patient may be up from about 0.01 to about 1,000 units; for example, up to about 500 units, and preferably in the range from about 80 to about 460 units per patient per treatment, although smaller of larger doses may be administered in appropriate circumstances such as up to about 50 units for the relief of pain and in controlling cholinergic secretions.
[0028] As the physicians become more familiar with the use of this product, the dose may be changed. In the Botulinum toxin type A, available from Porton, DYSPORT, 1 nanogram (ng) contains 40 units. 1 ng of the Botulinum toxin type A, available from Allergan, Inc., i.e., BOTOX®, contains 4 units. The potency of Botulinum toxin and its long duration of action mean that doses will tend to be administered on an infrequent basis. Ultimately, however, both the quantity of toxin administered and the frequency of its administration will be at the discretion of the physician responsible for the treatment and will be commensurate with questions of safety and the effects produced by the toxin.
[0029] In some circumstances, particularly in the relief of pain associated with sports injuries, such as, for example, charleyhorse, botulinum type F, having a short duration activity, is preferred.
[0030] The invention will now be illustrated by reference to the following nonlimiting examples.
[0031] In each of the examples, appropriate areas of each patient are injected with a sterile solution containing the confirmation of Botulinum toxin. Total patient doses range from about 0.01 units to 460 units. Before injecting any muscle group, careful consideration is given to the anatomy of the muscle group, the aim being to inject the area with the highest concentration of neuromuscular junctions, if known. Before injecting the muscle, the position of the needle in the muscle is confirmed by putting the muscle through its range of motion and observing the resultant motion of the needle end. General anaesthesia, local anaesthesia and sedation are used according to the age of the patient, the number of sites to be injected, and the particular needs of the patient. More than one injection and/or sites of injection may be necessary to achieve the desired result. Also, some injections, depending on the muscle to be injected, may require the use of fine, hollow, teflon-coated needles, guided by electromyography.
[0032] Following injection, it is noted that there are no systemic or local side effects and none of the patients are found to develop extensive local hypotonicity. The majority of patients show an improvement in function both subjectively and when measured objectively.
EXAMPLE 1
The Use of Botulinum Toxin Type in the Treatment of Tardive Dyskinesia
[0033] A male patient, age 45, suffering from tardive dyskinesia resulting from the treatment with an antipsychotic drug, such as Thorazine or Haldol, is treated with 150 units of Botulinum toxin type B by direct injection of such toxin into the facial muscles. After 1-3 days, the symptoms of tardive dyskinesia, i.e., orofacial dyskinesia, athetosis, dystonia, chorea, tics and facial grimacing, etc. are markedly reduced.
EXAMPLE 1(a)
[0034] The method of Example 1 is repeated, except that a patient suffering from tardive dyskinesia is injected with 50-200 units of Botulinum toxin type C. A similar result is obtained.
EXAMPLE 1(b)
[0035] The method of Example 1 is repeated, except that a patient suffering from tardive dyskinesia is injected with 50-200 units of Botulinum toxin type D. A similar result is obtained.
EXAMPLE 1(c)
[0036] The method of Example 1 is repeated, except that a patient suffering from tardive dyskinesia is injected with 50-200 units of Botulinum toxin type E. A similar result is obtained.
EXAMPLE 1(d )
[0037] The method of Example 1 is repeated, except that a patient suffering from tardive dyskinesia is injected with 50-200 units of Botulinum toxin type F. A similar result is obtained.
EXAMPLE 1(e)
[0038] The method of Example 1 is repeated, except that a patient suffering from tardive dyskinesia is injected with 50-200 units of Botulinum toxin type G. A similar result is obtained.
EXAMPLE 2
The Use of Botulinum Toxin Type B in the Treatment of Spasmodic Torticollis
[0039] A male, age 45, suffering from spasmodic torticollis, as manifested by spasmodic or tonic contractions of the neck musculature, producing stereotyped abnormal deviations of the head, the chin being rotated to one side, and the shoulder being elevated toward the side at which the head is rotated, is treated by injection with 100-1,000 units of Botulinum toxin type E. After 3-7 days, the symptoms are substantially alleviated; i.e., the patient is able to hold his head and shoulder in a normal position.
EXAMPLE 2(a)
[0040] The method of Example 2 is repeated, except that a patient suffering from spasmodic torticollis is injected with 100-1,000 units of Botulinum toxin type B. A similar result is obtained.
EXAMPLE 2(b)
[0041] The method of Example 2 is repeated, except that a patient suffering from spasmodic torticollis is injected with 100-1,000 units of Botulinum toxin type C. A similar result is obtained.
EXAMPLE 2(c)
[0042] The method of Example 2 is repeated, except that a patient suffering from spasmodic torticollis is injected with 100-1,000 units of Botulinum toxin type D. A similar result is obtained.
EXAMPLE 2(d)
[0043] The method of Example 2 is repeated, except that a patient suffering from spasmodic torticollis is injected with 100-1,000 units of Botulinum toxin type E. A similar result is obtained.
EXAMPLE 2(e)
[0044] The method of Example 2 is repeated, except that a patient suffering from spasmodic torticollis is injected with 100-1,000 units of Botulinum toxin type F. A similar result is obtained.
EXAMPLE 2(f)
[0045] The method of Example 2 is repeated, except that a patient suffering from spasmodic torticollis is injected with 100-1,000 units of Botulinum toxin type G. A similar result is obtained.
EXAMPLE 3
The Use of Botulinum Toxin in the Treatment of Essential Tremor
[0046] A male, age 45, suffering from essential tremor, which is manifested as a rhythmical oscillation of head or hand muscles and is provoked by maintenance of posture or movement, is treated by injection with 50-1,000 units of Botulinum toxin type B. After two to eight weeks, the symptoms are substantially alleviated; i.e., the patient's head or hand ceases to oscillate.
EXAMPLE 3(a)
[0047] The method of Example 3 is repeated, except that a patient suffering from essential tremor is injected with 100-1,000 units of Botulinum toxin type C. A similar result is obtained.
EXAMPLE 3(b)
[0048] The method of Example 3 is repeated, except that a patient suffering from essential tremor is injected with 100-1,000 units of Botulinum toxin type D. A similar result is obtained.
EXAMPLE 3(c)
[0049] The method of Example 3 is repeated, except that a patient suffering from essential tremor is injected with 100-1,000 units of Botulinum toxin type E. A similar result is obtained.
EXAMPLE 3(d)
[0050] The method of Example 3 is repeated, except that a patient suffering from essential tremor is injected with 100-1,000 units of Botulinum toxin type F. A similar result is obtained.
EXAMPLE 3(e)
[0051] The method of Example 3 is repeated, except that a patient suffering from essential tremor is injected with 100-1,000 units of Botulinum toxin type G. A similar result is obtained.
EXAMPLE 4
The Use of Botulinum Toxin in the Treatment of Spasmodic Dysphonia
[0052] A male, age 45, unable to speak clearly, due to spasm of the vocal chords, is treated by injection of the vocal chords with Botulinum toxin type B, having an activity of 80-500 units. After 3-7 days, the patient is able to speak clearly.
EXAMPLE 4(a)
[0053] The method of Example 4 is repeated, except that a patient suffering from spasmodic dysphonia is injected with 80-500 units of Botulinum toxin type C. A similar result is obtained.
EXAMPLE 4(b)
[0054] The method of Example 4 is repeated, except that a patient suffering from spasmodic dysphonia is injected with 80-500 units of Botulinum toxin type D. A similar result is obtained.
EXAMPLE 4(c)
[0055] The method of Example 4 is repeated, except that a patient suffering from spasmodic dysphonia is injected with 80-500 units of Botulinum toxin type E. A similar result is obtained.
EXAMPLE 4(d)
[0056] The method of Example 4 is repeated, except that a patient suffering from spasmodic dysphonia is injected with 80-500 units of Botulinum toxin type F. A similar result is obtained.
EXAMPLE 4(e)
[0057] The method of Example 4 is repeated, except that a patient suffering from spasmodic dysphonia is injected with 8-500 units of Botulinum toxin type G. A similar result is obtained.
EXAMPLE 5
The Use of Botulinum Toxin Types A-G in the Treatment of Excessive Sweating, Lacrimation or Mucus Secretion or Other Cholinergic Controlled Secretions
[0058] A male, age 65, with excessive unilateral sweating is treated by administering 0.01 to 50 units, of Botulinum toxin, depending upon degree of desired effect. The larger the dose, usually the greater spread and duration of effect. Small doses are used initially. Any serotype toxin alone or in combination could be used in this indication. The administration is to the gland nerve plexus, ganglion, spinal cord or central nervous system to be determined by the physician's knowledge of the anatomy and physiology of the target glands and secretary cells. In addition, the appropriate spinal cord level or brain area can be injected with the toxin (although this would cause many effects, including general weakness). Thus, the gland (if accessible) or the nerve plexus or ganglion are the targets of choice. Excessive sweating, tearing (lacrimation), mucus secretion or gastrointestinal secretions are positively influenced by the cholinergic nervous system. Sweating and tearing are under greater cholinergic control than mucus or gastric secretion and would respond better to toxin treatment. However, mucus and gastric secretions could be modulated through the cholinergic system. All symptoms would be reduced or eliminated with toxin therapy in about 1-7 days. Duration would be weeks to several months.
EXAMPLE 6
The Use of Botulinum Toxin Types A-G in the Treatment of Muscle Spasms in Smooth Muscle Disorders Such as Sphincters of the Cardiovascular Arteriole, Gastrointestinal System, Urinary or Gall Bladder, Rectal, Etc.
[0059] A male, age 30-40, with a constricted pyloric valve which prevents his stomach from emptying, is treated by administering 1-50 units of Botulinum toxin. The administration is to the pyloric valve (which controls release of stomach contents into the intestine) divided into 2 to 4 quadrants, injections made with any endoscopic device or during surgery. In about 1-7 days, normal emptying of the stomach, elimination or drastic reduction in regurgitation occurs.
EXAMPLE 7
The Use of Botulinum Toxin Types A-G in the Treatment of Muscle Spasms and Control of Pain Associated with Muscle Spasms in Temporal Mandibular Joint Disorders
[0060] A female, age 35, is treated by administration of 0.1 to 50 units total of Botulinum toxin. The administration is to the muscles controlling the closure of the jaw. Overactive muscles may be identified with EMG (electromyography) guidance. Relief of pain associated with muscle spasms, possible reduction in jaw clenching occurs in about 1-3 days.
EXAMPLE 8
The Use of Botulinum Toxin Types A-G in the Treatment of Muscle Spasms and Control of Pain Associated with Muscle Spasms in Conditions Secondary to Sports Injuries (Charleyhorse)
[0061] A male, age 20, with severe cramping in thigh after sports injury is treated by administration of a short duration toxin, possible low dose (0.1-25 units) of preferably type F to the muscle and neighboring muscles which are in contraction (“cramped”). Relief of pain occurs in 1-7 days.
EXAMPLE 9
The Use of Botulinum Toxin Types A-G in the Treatment of Muscle Spasms and Control of Pain Associated with Muscle Spasms in Smooth Muscle Disorders Such as Gastrointestinal Muscles
[0062] A female, age 35, with spastic colitis, is treated with 1-100 units of Botulinum toxin divided into several areas, enema (1-5 units) delivered in the standard enema volume, titrate dose, starting with the lowest dose. Injection is to the rectum or lower colon or a low dose enema may be employed. Cramps and pain associated with spastic colon are relieved in 1-10 days.
EXAMPLE 9
The Use of Botulinum Toxin Types A-G in the Treatment of Muscle Spasms and Control of Pain Associated with Muscle Spasms in Spasticity Conditions Secondary to Stroke, Traumatic Brain or Spinal Cord Injury
[0063] A male, age 70, post-stroke or cerebral vascular event, is injected with 50 to 300 units of Botulinum toxin in the major muscles involved in severe closing of hand and curling of wrist and forearm or the muscles involved in the closing of the legs such that the patient and attendant have difficulty with hygiene. Relief of these symptoms occurs in 7 to 21 days.
EXAMPLE 10
The Use of Botulinum Toxin Types A-G in the Treatment of Patients with Swallowing Disorders
[0064] A patient with a swallowing disorder caused by excessive throat muscle spasms is injected with about 1 to about 300 units of Botulinum toxin in the throat muscles. Relief the swallowing disorder occurs in about 7 to about 21 days.
EXAMPLE 11
The Use of Botulinum Toxin Types A-G in the Treatment of Patients with Tension Headache
[0065] A patient with a tension headache caused by excessive throat muscle spasms is injected with about 1 to about 300 units of Botulinum toxin in muscles of the head and upper neck. Relief the tension headache occurs in about 1 to about 7 days.
[0066] Although there has been hereinabove described a use of Botulinum toxins for treating various disorders, conditions and pain, in accordance with the present invention, for the purpose of illustrating the manner in which the invention may be used to advantage, it should be appreciated that the invention is not limited thereto since many obvious modifications can be made, and it is intended to include within this invention any such modifications as will fall within the scope of the appended claims. Accordingly, any and all modifications, variations, or equivalent arrangements which may occur to those skilled in the art, should be considered to be within the scope of the present invention as defined in the appended claims. | A method and composition for treating a patient suffering from a disease, disorder or condition and associated pain include the administration to the patient of a therapeutically effective amount of a neurotoxin selected from a group consisting of Botulinum toxin types A, B, C, D, E, F and G. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a rotation detection apparatus for determining the degree of rotation of a rotational axis driven rotationally.
Actuators for rotating a rotational axis, and controllers for carrying out complicated controls such as a numerical control of rotation and a feed back control in response to rotational speed, have been proposed.
For example, when an arm of a robot for industrial use rotates to some predetermined angle, a predetermined operation such as welding or deburring is executed. Such rotation detection of a rotational axis is an indispensable technique today, when a lot of automatic controls are used and a lot of devices are prepared. Digital techniques of rotation detection are particularly prevalent since they are quite precise and the price of digital circuits is going down. In digital rotation detection, pulse signals in response to a rotation angle by a rotary encoder, etc. are received, and rotation of the rotational axis is determined by a count of the pulse signals.
Both an absolute type and an incremental type of encoder are known. Absolute encoders are capable of detecting rotation on the spot of switch-on, but they are expensive. Incremental encoders are cheap, but they are incapable of detecting rotation of the spot on switch-on, but rather require provision of an origin (zero point) by some apparatus. Once the origin is given degree of rotation can be detected by detecting relative rotation therefrom by integration.
Today, incremental encoders are more often used as rotation detectors because of their inexpensiveness, and when a lot of encoders are required incremental encoders are more often used.
Detection of the zero point of the rotational axis is indispensable to the use of an incremental type encoder as a rotation detector. One method for detection of the zero point is to detect a specific position of an output axis by a position detection sensor, and to determine the origin when an origin signal, which is output once every rotation of the incremental type encoder provided at an input axis connected to the output axis via a reduction gear, coincides with the position signal.
Such a rotation detector for the rotational axis, however, is not sufficient when the rotational axis rotates a lot, since the following problems remain. An absolute type rotation detector has a finite detection capacity and cannot detect a rotating degree of the rotational axis infinitely. Incremental type rotation detectors are much more often used when infinite rotations of the rotational axis are detected, but the following origin-determination is required. When the rotational axis rotates finitely, one point in that limited rotation is taken as the origin, but when the rotational axis rotates infinitely, precise origin determination cannot be obtained even if a special position on the output axis is taken as the origin.
Thus, an origin on the input axis does not necessarily coincide with that on the output exis even when the output axis is on the origin determination position since the rotation is detected at the input axis. In case of a reduction ratio 1:1, for example, to reassure the origin by rotating the output axis once or more, the position to be detected by the position detection sensor cannot be detected except when there is a specific relation (every ten rotations of the output axis), since with an output of once/rotation of the rotational axis, an output origin signal detected by the rotation detection sensor is generated per 1/1.1 rotation.
As can be seen in this case, when higher rotation is required, in order to set the origin in switching on or off, the output axis must be rotated until a simultaneous output of the origin signals of both the position detection sensor and the rotation detector is achieved.
However, in general, since the reduction ratio is large and a decimal part is long, considerable rotation is required to gain the origin determination position.
The pulse signals from the rotary encoder, etc. are continuously input as long as the rotational axis rotates. An overflow always occurs at some point, since the counting capacity is not infinite.
Thus, the rotation of the rotational axis was conventionally detected by setting the maximum in advance, for example, under such limitation as only one clockwise or counterclockwise rotation. This characteristic has affected the operation of the robot in its efficiency, since the mode of operation must have been limited. For example, when applying to the robot for industrial use, to rotate an arm counterclockwise for one operation and further counterclockwise for the next operation, the arm must be returned to the original position by rotating it clockwise after the first operation before proceeding to the next operation. It is one of the factors that generate a disadvantageous influence to decrease moving efficiency of the robot.
SUMMARY OF THE INVENTION
It is an object of this invention to solve the aforementioned problems by providing an improved rotation detection sensor of the rotational axis which can detect the rotation precisely even when the rotational axis rotates one way and at a high speed.
The construction of this invention resides in a rotation detection apparatus which overcomes the aforementioned problems including: a reduction gear with integer reduction ratio, having an input axis which is connected to a rotational axis of a driving source; a position detection sensor connected to an output axis of the reduction gear for generating a position signal once every rotation of the output axis; a rotation angle detection sensor provided to the input axis for providing an output rotation signal in response to a rotation of the input axis and for providing a simultaneous output of the position signal and one of the rotation signals; and a counting circuit responsive to the position signal and the rotation signal for counting the rotation of the rotational axis.
The reduction gear in this invention receives an input rotation from a power source, for example, motors, etc., and rotates the output axis at the integer reduction ratio. Thus, the most simple example of this is the one which has a reduction mechanism with a spur gear having integer teeth ratio. The position detection sensor is included in the output axis system which is driven by the output axis and provides the position signal every rotation of the output axis. The position signal is output upon every appearance of some characteristic, as for example a reflecting disk or a magnet attached at some fixed position on the output axis.
The rotation angle detection sensor outputs a rotation angle signal in response to the rotation angle of the intput axis. The input axis rotates integer times per rotation of the output axis by the operation of the reduction gear. Thus the rotation angle signal from the rotation angle detection sensor is always output plural times per rotation while the position signal generated by the position detection sensor is output once every rotation of the output axis. By this invention, it is intended to achieve coincidence of the position signal and one of the rotation angle signals by previously regulating these two signals.
For example, when a conventional rotary encoder is used as a rotation angle detection sensor, many detector holes (phase A, phase B) drilled along the circle with phase difference are used to determine the rotation, while an output generated by the detector hole drilled only once. On the circle (phase C) is designed to be provided in synchronism with the position signal.
A counting circuit is constructed of well-known counters, etc., which count up or count down whenever the position signal and the rotation angle signal generated by the position detection sensor and the rotation angle detection sensor are input, and counts the rotation of the rotational axis.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a brief diagram showing a construction of a rotary table embodying the present invention, including a rotation detection apparatus;
FIG. 2 is a construction of a rotary encoder;
FIG. 3 is a phase diagram illustrative of the output of a proximity sensor and a rotary encoder;
FIG. 4 is a brief diagram illustrative of the application of this embodiment to a robot for industrial use.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
If a one way rotation is continually kept going after switching-on, a counter overflows, since an infinite counting is impossible. Continuous rotation without overflow, however, can be obtained if the counter is reset by replacement of an origin before the overflow.
However, a complicated and time-consuming operation which resumes after determining the origin by replacement of the origin to a new position is required, since the origin determination in the foregoing is only possible on a predetermined origin determination point.
In the mode of the embodiment of this invention, if the result by a rotation angle detection sensor is judged to be over the limit of the counting capability of a counting circuit, a control circuit changes the count to a smaller number. In this mode of the embodiment, with the foregoing, the control of the rotation having as much precision as a numerically controlled conventional rotational axis, and a one-way high-speed rotation being achieved by rewriting a counter number to replace the rotation angle of an output axis thereto within ±180° before the counting circuit, such as counters which add or subtract pulses generated by the rotation angle detection sensor at a high speed rotation, overflows without the operation of the origin determination can be obtained. In another mode of the embodiment, which has as good of operational effects as the aforementioned mode, the control circuit is so constituted as: to operate by dividing the value C detected by a rotation detection sensor into nxCo, the multiple of n and Co, and a fraction m (whose amplitude is below Co), where n is an integer coefficient and Co corresponds to one turn of an output axis detected by the rotation detection sensor; to compare the integer coefficient n of the Co detected by the rotation detection sensor with a limitative coefficient 1 which corresponds to a limitative count of the counter circuit; and to replace the count of the count circuit with the fraction at the time when the coefficient exceeds the limitative coefficient 1.
The following operation by the following expression for the fraction m, is also available:
m=C-F(C/Co)×Co
where F(C/Co) is an integer obtained by half-adjust of the fraction of the division C/Co.
A detailed description of the present invention and the embodiment will now be provided.
FIG. 1 shows a brief diagram of a rotary table including a rotation detection apparatus of the rotational axis of the embodiment. In the drawings, 10 denotes a table of the rotary table, integrated into an upper portion of a large spur gear 20 and pivotally supported by two bearings 12 and 14 with a central axis A. The large spur gear 20 is engaged with a small spur gear 30 and the gear ratio of large and small gears is 8:1. A motor 40 rotates the small spur gear 30 around an axis B. 50 denotes a drive circuit which drives the motor 40 by armature current.
Also provided in this system are two sensors. One of them is a position sensor comprising a magnet 16 which is a to-be-detected member put on one point on a lower surface of the table and a proximity switch 18 which provides an electronic control circuit 60 with an output signal by the motion of an inner armature iron strip movable when the magnet approaches. The other sensor is a rotary encoder 42 provided at the rotational axis of the motor 40. Detailed construction of the rotary encoder 42 is shown in FIG. 2. The rotary encoder 42 comprises a disk 43 which has light-passing holes on three concentric circles. The holes corresponding to a phase A and a phase B on the outermost and on the middle circles, respectively, have the phase difference of 1:4 to detect the direction of the rotation of the disk 43 and its rotation angle. A phase C on an innermost circle with only one hole is to detect a rotary position of disk 43. Opposing on either side of this disk 43 are light emitting portions 44 and light receiving portions 45 for the various phases. When the light emitting portion 44 emits light by the output of the electronic control circuit 60, the disk 43 rotates and the output signal is generated at the light receiving portions 45 and sent to the electronic control circuit 60 when either of the light-passing holes reaches a position where the light emitting portions 44 and the light receiving portions 45 are opposed.
The electronic control circuit 60 in FIG. 1 includes an input and output port 61 which receives the outputs of the proximity switch 18 and the rotary encoder 42, and provides electricity or a control signal to the drive circuit 50 and the rotary encoder 42; a counter 62 which counts up or counts down inputs through the input and output port 61; and a counter control circuit 63 which controls the contents of the counter 62.
The phases of the two sensors are so determined as to generate the detection output of the rotation detection apparatus of the rotational axis of this embodiment as shown in FIG. 3. Since 8 rotations of the small spur gear 30 are required for one turn of the table 10, the output of phase C of the rotary encoder 42 is generated every 360°/8=45°. The proximity switch 18 provided at the table 10, which outputs once every rotation, is predetermined to output simultaneously with either of the outputs of the rotary encoder 42. In some limited rotation angle around the table 10, the output of the proximity switch 18 might continuously occur, but the output of phase C within that limit is only one. Thus, the phase of the sensor is quite precisely determined.
The rotation of the table 10 is detected by the rotation detection apparatus of the rotational axis in the following manner.
First, the position of simultaneous outputs of the rotary encoder 42 and the proximity switch 18 in FIG. 3 is selected for an operational origin of the table 10. When the table 10 begins to rotate from this operational origin, the rotation angle of the table 10 is counted up to the counter 62 with as much precision as the numbers of the light-passing holes of phases A and B by their pulse putput, since the rotary encoder 42 rotates once every 45° rotation of the table 10. The holes in phases A and B are dug with a phase difference of 1:4 as mentioned above, and the reverse rotation of the table 10, where a counter 62 is counted down, also can be detected.
The precision for detecting the rotation angle of the table 10 according to the counter 62 is eight times better than that gained by the rotary encoder 42, since the table 10 rotates once every 8 rotations of the rotary encoder.
For the determination of the origin, the position of the origin of the output axis at which the phase C output by the rotary encoder and output by the proximity switch are simultaneously detected is only once every rotation of the output axis. Since a reduction ratio is an integer, even if the electronic control circuit is deenergized at any position in the course of the high-speed output axis rotation, and re-determination of the origin is executed, the same position of the output axis can be obtained.
At high-speed rotation of the table 10 like this, overflow of the counter 62 may occur, since its capacity is not infinite. However, the counter control circuit 63 always replaces the contents of the counter 62 with the result of the following equation. That is an operation is performed for replacement of the contents C of the counter 62 with the calculation result θ, (θ=C-A'×Co), where A' is a half-adjust of the fraction of the division A=C/Co, C is the contents of the counter 62, and Co is the count of the rotary encoder 42 output every rotation of the table 10.
Accordingly the contents of the counter 62 are updated to the value representative of the rotation angle of ±180° from the operational origin to thereby avoid the overflow.
FIG. 4 shows one application of this rotary table system to which the rotation detection apparatus of the embodiment is attached.
In the drawings, 100 denotes the rotary table with four acetabulums 102 on it. 106 denotes a window glass for a vehicle to be dealt with, fixed on the table by the acetabulums 102. While the window glass 106 rotates once by the rotary table, a tool for the application of an adhesive agent, included in an arm of a robot 110, travels properly to accomplish the application of the adhesive agent along the whole frame of window glass 106.
According to the rotation detection apparatus of the invention, the rotation of the output axis can be determined by the rotation angle signal from the position where both the position signal in response to a position detection sensor and the rotation angle signal via a rotation angle detection sensor are output simultaneously. Since the reduction ratio of the reduction gear is an integer, at least one position exists where the position detection sensor determines during one rotation of the rotational axis in synchronism with the output of one of many holes of the rotation angle detection sensor and with the detector hole (phase C) by the rotation angle detection sensor.
With high-speed rotation of the rotational axis, the point which coincides with the output axis exists at least once every rotation of the output axis. Thus, the origin determination within one rotation of the output axis at the time of switch on after arbitrary cutting-off is made possible. | The present invention provides a rotation detection apparatus of a rotational axis connected to an output axis system of a reduction gear to count the rotation of a rotational axis driven rotationally, including a reduction gear, with an integer reduction ratio, whose rotational axis of a driving source is connected to an input axis. The apparatus provides a position signal once every rotation of the output axis, and a rotation angle signal in response to the rotation angle of said input axis is output to correlate said output position signal with one of said rotation angle signals to count the rotation of the rotational axis by these position and rotation angle signals. An accurate rotation can be detected even at one-way high-speed rotation. | 6 |
REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of priority to U.S. provisional patent application Ser. No. 61/465,905, filed Mar. 25, 2011, the entire disclosure of which is explicitly incorporated by reference herein.
FIELD
[0002] This invention relates to an apparatus and methods for forming polymeric devices, especially fluidic devices used as conduits for controlling fluid flow.
BACKGROUND
[0003] Polymeric resins are used to produce a variety of manufactured articles and devices. Particularly useful in this regard are thermoplastic resins, which can be readily molded into almost any shape and comprise almost any moldable feature by the application of sufficient heat and pressure to melt the resin. In the practice of making articles and devices using thermoplastic resins, a mold is used. In some cases, the mold is made from a metallic substrate or by photolithography on a glass or silicon base. In other cases, the mold is an elastomeric tool made from a silicone rubber that has been cast against a master part, intended for replication.
[0004] Particularly useful devices that can be made from thermoplastic and other polymeric resins are fluidics devices. The use of fluidic devices, particularly microfluidic devices, for chemical or biological assays and syntheses has increased rapidly over the last decade. Examples of the uses to which such devices have been put include immunoassays, enzyme assays, protein crystallization, cell separation, and nucleic acid amplification. While the particular requirements are as broad as the class of assays and syntheses itself, most fluidic devices including microfluidic devices share a few common functions: one or a plurality of fluids, particularly in microliter quantities, are introduced onto the device and the fluids are distributed and metered to defined sites within the device where an assay or synthesis occurs. For microfluidics devices, typically these devices may be as small as a postage stamp or as large as a compact disc. On a given microfluidics device may be found tens to hundreds of input ports, channels, incubation, reaction or detection chambers and, at times, exit ports connected and arrayed in an application-specific microfluidic network. Typically, channels on such microfluidic devices have cross-sectional dimensions ranging from several microns to hundreds of microns, whereas the various ports and chambers that serve as connecting nodes for the microfluidic network are often sized to accommodate fluid volumes ranging from a few to hundreds of microliters. In some instances, surfaces within the microfluidic network are textured with submicron size posts or divots or other features that may be used as diffractive elements or, when functionalized with the appropriate chemistry, as affinity columns for select molecular or cellular species.
[0005] As such devices have become more prevalent, polymeric resins have been more frequently used for fabricating such devices instead of glass or silicon. The advantages of using polymeric resins, particularly thermoplastic embodiments thereof, include reduced cost, adequate chemical compatibility and optical properties. When polymeric resins are used, embossing and molding are the preferred methods for forming the devices and the microfluidic components thereof. Using either method, resin is brought in contact with a substrate or tool comprising a negative replica of the structures, such as fluidics structures or microfluidics structures, desired on the device. The application of an appropriate amount of pressure at a sufficient temperature (i.e., higher than the melting, or glass transition temperature, of the thermoplastic resin) and for an adequate amount of time produce the device.
[0006] The prior art describes embossing apparatus with means for heating polymeric resins, forcing a tool against the resin with a sufficient amount of pressure to form the resin against the tool, cooling the formed resin and the tool under applied pressure, releasing the pressure from the formed resin and tool and then separating the formed resin from the tool. These apparatus require high forces to push the flowing polymer throughout the tool and means for actively cooling the tools before the pressure is released. These requirements, in turn, add to the size of an embossing apparatus and also add to the number of components used for fabrication, and both contributions typically lead to increased costs to fabricate an embosser.
[0007] Thus, there is a need for improved apparatus and methods for forming polymeric devices.
SUMMARY
[0008] Apparatus and methods for forming polymeric devices are disclosed herein. The objective of this invention is an apparatus and method for performing fixed-temperature, vacuum-embossing of microstructured, thermoplastic parts. A typical sequence of process steps include:
[0009] setting the process temperature;
[0010] placing an embossing tool and thermoplastic resin between the embossing platens;
[0011] evacuating the embossing chamber;
[0012] closing the platens with a defined force;
[0013] embossing the blank with the tool for a pre-determined amount of time;
[0014] removing the tool and resin assembly from the instrument;
[0015] allowing the assembly to cool below the glass transition of the embossed part on the bench in an ambient environment;
[0016] and separating the embossing tool from the embossed part.
[0017] We have found that, in combination with vacuum, a fixed-temperature embossing process can produce parts with features suitable for microfluidic devices.
[0018] The disclosed apparatus offers the following advantages over existing equipment for embossing of thermoplastic parts:
[0019] Operating the heaters at a constant temperature, rather than cycling from the forming temperature to ambient or to an intermediate temperature, allows parts to be formed in less time. This mode of operation is facilitated by the use of a holder for the tool and part that allows removal from the apparatus at the molding temperature. The constant temperature operation avoids the need for a cooling subsystem, simplifying the machine and reducing cost.
[0020] The use of vacuum during the molding operation is important in reducing the amount of trapped air in the tool. The air inside features or pockets in the tool must be compressed to reduce its volume and the related size of unfilled regions or defects in the formed part. In the mode of operation mentioned in advantage [0019] in which the tool and part are removed at elevated temperature, if vacuum is not used, the trapped air would expand back to its original volume before the plastic cools below its glass transition temperature, with the potential to cause significant defects.
[0021] The application of vacuum during the molding operation, in addition to improving the results for constant temperature operation, provides the benefit of reducing the amount of force required to be applied to the tool and part in order to move plastic through the mold. The lower force levels allow parts to be formed more accurately with less deflection of the soft tools. The lower forces also allow the embossing machine to be constructed with lighter and less-costly components than are needed in other machines.
BRIEF DESCRIPTION OF THE FIGURES
[0022] Further description of the invention, summarized above, can be found in the embodiments illustrated in the appended figures. It is to be noted, however, that the appended figures are only provided as illustrative 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.
[0023] FIG. 1 schematically a cross-sectional view of an embossing apparatus.
[0024] FIGS. 2A-B show a spike and channel embossed in a thermoplastic blank.
[0025] FIGS. 3A-B shows posts embossed in a thermoplastic film.
[0026] FIG. 4 shows channels and reservoirs embossed from in a thermoplastic blank.
[0027] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.
DETAILED DESCRIPTION
[0028] Embodiments of the present invention include apparatus and methods for forming polymeric devices. The inventive apparatus provides fixed-temperature, vacuum embossing with sufficient force and temperature to replicate hard and even soft or elastomeric tools to form thermoplastic devices with microscale features, macroscale features alone or in combination.
[0029] Microscale features means raised (or depressed) features with in-plane dimensions from a few microns to hundreds of microns and heights (or depths) of a few microns to hundreds of microns and height to width ratios from less than one to over ten. Macroscale features means raised (or depressed) features with in-plane dimensions from a few millimeters to several centimeters and heights (or depths) of a few millimeters to several centimeters.
[0030] The formed features may also be through-holes. Through-holes may be fabricated by forming thermoplastic resin between two patterned tools each with raised features that also make contact when the tools are pressed together and against the interior thermoplastic resin.
[0031] The use of two tools each patterned with the same or different patterns can be used to form microscale and macroscale features on the opposing sides of a polymeric device along with through-holes to allow fluidic communication between the features of each side of the device.
[0032] While typical polymeric devices are planar, the present invention also provides the capability to form non-planar or curved devices with microscale, macroscale and through-hole features.
[0033] The polymeric devices may be formed from a variety of thermoplastic materials. Injection moldable thermoplastics including cyclic olefin copolymers, acrylics, polypropylenes and polycarbonates are preferred resins although other thermoplastics with sufficiently high melt flow index at temperatures in the range 100° C. to 250° C. may also be used with the apparatus and methods of this invention. Extruded thermoplastic films that can flow at elevated temperature may be placed against one tool or between two tools to allow thermoforming of microscale and macroscale features on one or both sides of the film and through-holes to provide communication between these features.
[0034] FIG. 1 illustratively depicts a cross-sectional view of an embodiment of the embossing apparatus of this invention. Key components of this embodiment include a vacuum cover 101 , an upper frame 102 , an air cylinder 103 , an upper heater assembly moveable support 104 , guide posts 105 , a set of upper and lower tools 106 , a tool support tray 107 , heated plates 108 , thermal insulation 109 , a vacuum gasket 110 and a base 111 .
[0035] Not shown but important for the operation of this embodiment is the presence of thermoplastic resin between the upper and lower tools 106 . This resin may take the form of resin beads, a preformed (previously compression molded or injection molded) shape or an extruded film.
[0036] In a preferred embodiment, the heated plates 108 are aluminum, copper or other thermally conductive material and are heated with cartridge heaters embedded within the plate bodies or blanket heaters attached to the plate surfaces distal to the embossing surfaces. Not shown but useful for the operation of this embodiment are temperature sensors in the upper and lower heated plates that, in combination with a temperature controller, provide closed-loop control of the process temperature on the upper and lower embossing surfaces. The thermal insulation maintains some of the heat within the heated plates, thereby lowering the power dissipation to the moveable support, guide posts, vacuum cover and other components of the apparatus.
[0037] In a preferred embodiment, the air cylinder 103 forces the upper heated plate against the upper tool, resin and lower tool assembly, forcing them against the lower heated plate. In a preferred embodiment, electrical and pneumatic connections are made through sealed through-holes in the base of the apparatus and electrical and pneumatic power sources and control modules external to the apparatus.
[0038] Certain preferred embodiments of the apparatus and methods of the invention are described in greater detail in the following sections of this application and in the figures.
EXAMPLE 1
[0039] This example describes the fabrication of pre-forms or blanks from thermoplastic resin beads.
[0040] Approximately 2 g of cyclic olefin copolymer resin beads (COC 8007 X10 from Topas) was added to a 30 mm diameter, 3 mm deep blind hole in a silicone rubber tool and a 3 mm thick silicone rubber sheet was placed on top of the resin-filled hole to make a resin/tool assembly. The embossing apparatus was heated to 195° C., the resin/tool assembly was placed between the heated plates, the vacuum was engaged to reach a level of 20 inches of mercury and after 7 minutes of equilibration, the plates were forced together. The pressure on the 30 mm diameter section of resin beads was approximately 0.3 N/mm 2 . After 20 minutes of applied pressure and heat, the vacuum and pressure were released, and the resin/tool assembly was removed from the apparatus and left to cool on the bench. After 7 minutes of passive cooling, the formed thermoplastic disk was removed from the rubber tool.
[0041] The disk was observed to be free of voids.
EXAMPLE 2
[0042] This example describes the embossing of a spike and channel from a thermoplastic blank.
[0043] A pre-formed thermoplastic blank of cyclic olefin copolymer (COC 8007 X10 from Topas) with diameter approximately 30 mm was placed on a silicone rubber sheet. A patterned elastomeric tool was made from a two-part silicone (Mold Max 60 from Smooth-On) by casting and curing the rubber against a part that contained a spike and a microfluidic channel. The patterned elastomeric tool was placed on top of the pre-formed thermoplastic blank, and this assembly was placed on a tray, which was then inserted into the embossing apparatus.
[0044] The embossing apparatus was heated to 195° C., the assembly was placed between the heated plates, the vacuum was engaged to reach a level of 20 inches of mercury and after 7 minutes of equilibration, the plates were forced together. The pressure on the 30 mm diameter pre-formed thermoplastic blank was approximately 0.15 N/mm 2 (21.8 lbs/in 2 ). After 2 minutes of applied pressure and heat, the vacuum and pressure were released, and the assembly was removed from the apparatus and left to cool on the bench. After 7 minutes of passive cooling, the patterned elastomeric tool was separated from the now formed or patterned thermoplastic part.
[0045] FIG. 2( a ) is an oblique optical micrograph showing a section of the part that was formed during this fixed-temperature, vacuum embossing process. The part includes a well-defined spike and microfluidic channel. To establish a scale for this figure, note that the measured width of the microfluidic channel is approximately 0.8 mm. The voids seen in FIG. 2( a ) were present in the pre-formed blank and were not a result of the process for embossing the spike and channel.
[0046] In order to understand the effect of vacuum on the embossed features, the above process was repeated without vacuum (at ambient pressure).
[0047] FIG. 2( b ) is an oblique optical micrograph showing a section of the formed part. The part includes a poorly-defined spike and microfluidic channel. To establish a scale for this figure, note that the measured width of the microfluidic channel is approximately 0.8 mm.
[0048] This example shows the advantages of using vacuum with this embossing process.
EXAMPLE 3
[0049] This example describes the embossing of a microposts from a thermoplastic film.
[0050] An extruded film of cyclic olefin copolymer (COC 9506 from Topas) with with length, width and thickness approximately 75 mm, 25 mm and 0.04 mm, respectively, was placed on patterned elastomeric tool. The tool was made from a two-part silicone ((Shin Etsu KE-1600 and CX-832) by casting and curing the rubber against an etched silicon part with microscale posts. The post diameters and heights are approximately 100 microns. A non-patterned elastomeric tool was then placed on top of the extruded film, and this assembly was placed on a tray, which was then inserted into the embossing apparatus.
[0051] The embossing apparatus was heated to 195° C., the assembly was placed between the heated plates, the vacuum was engaged to reach a level of 20 inches of mercury and after 7 minutes of equilibration, the plates were forced together. The pressure on the 30 mm diameter pre-formed thermoplastic blank was approximately 0.15 N/mm 2 . After 2 minutes of applied pressure and heat, the vacuum and pressure were released, and the assembly was removed from the apparatus and left to cool on the bench. After 7 minutes of passive cooling, the patterned elastomeric tool was separated from the now formed or patterned thermoplastic part.
[0052] FIG. 3( a ) is an oblique optical micrograph showing a section of the part that was formed during this fixed-temperature, vacuum embossing process. The part includes a well-defined microposts. To establish a scale for this figure, note that the approximate diameter of an individual post is 100 microns.
[0053] In order to understand the effect of vacuum on the embossed features, the above process was repeated without vacuum (at ambient pressure).
[0054] FIG. 3( b ) is an oblique optical micrograph showing a section of the formed part. The part includes a majority of poorly-defined microposts with a smaller number of better-defined microposts. To establish a scale for this figure, note that the approximate diameter of an individual post is 100 microns.
[0055] This example shows the advantages of using vacuum with this embossing process.
EXAMPLE 4
[0056] This example describes the embossing of a polymeric device with channels and reservoirs from a pre-formed thermoplastic blank.
[0057] A pre-formed thermoplastic blank of cyclic olefin copolymer (COC 8007 X10 from Topas) with length, width and thickness approximately 75 mm, 25 mm and 1 mm, respectively, was placed on a silicone rubber sheet. A patterned elastomeric tool was made from a two-part silicone (Shin Etsu KE-1600 and CX-832) by casting and curing the rubber against a machined part with microfluidic channels and reservoirs. The patterned elastomeric tool was placed on top of the pre-formed thermoplastic blank, and this assembly was placed on a tray, which was then inserted into the embossing apparatus.
[0058] The embossing apparatus was heated to 195° C., the assembly was placed between the heated plates, the vacuum was engaged to reach a level of 20 inches of mercury and after 7 minutes of equilibration, the plates were forced together. The pressure on the 75 mm by 25 mm pre-formed thermoplastic blank was approximately 0.15 N/mm 2 . After 10 minutes of applied pressure and heat, the vacuum and pressure were released, and the assembly was removed from the apparatus and left to cool on the bench. After 7 minutes of passive cooling, the patterned elastomeric tool was separated from the formed thermoplastic part.
[0059] FIG. 4 is an oblique optical micrograph showing a section of the formed part. The part includes well-defined fluidic channels and reservoirs. To establish a scale for this figure, note that the measured width of the reservoir at the top right of the micrograph is approximately 3.6 mm and the measured width of the largest channel is approximately 250 microns. | This invention relates to an apparatus and methods for forming polymeric devices, especially fluidic or microfluidic devices used as conduits for controlling fluid flow. Such devices have important applications in chemistry and biology including immunoassays, enzyme assays and cell separation processes. The invention claims the use of fixed-temperature heating of thermoplastic resin in combination with vacuum and low pressure on the tool in order to rapidly produce good quality devices. The combination of features claimed in the invention is important because it enables simple, lightweight, economical equipment to be constructed to fabricate useful polymeric devices. | 1 |
FIELD OF THE INVENTION
[0001] The present invention is directed to artificial climbing walls. More specifically, the present invention is directed to a wall-climbing accessory for an artificial climbing wall.
BACKGROUND OF THE INVENTION
[0002] The sport of rock climbing is becoming more popular as a means of recreation. In order to develop the necessary skills to participate in this sport, many individuals practice on a simulation device that typically includes a climbing wall containing a plurality of man made climbing holds fastened thereto. Climbing of these man made walls has also become a sport of its own, with walls being designed to accommodate the various skill levels of climbers. In the United States, climbers use a standard rating system to describe the difficulty of different routes. There are six classes in this system, ranging from class one (normal walking) through hiking, scrambling and then climbing at class five. Everything known as “rock climbing” falls in class five. Class six are rock walls that are so smooth that there is no way to climb them without artificial aids (i.e. special climbing ladders or equipment). Within class five there are fourteen different levels that break down in the following manner: 5.0 through 5.4—beginner level which is easy to climb, like a ladder. 5.5 through 5.7—intermediate level which is climbable in normal shoes or boots but requiring more skill. 5.8 through 5.10—experienced level, which requires climbing shoes, experience and strength. 5.11 through 5.12—expert level that perhaps only the top 10% of climbers in the world can climb these routes. 5.13 through 5.14—elite level which can only be climbed by the best of the best.
[0003] The basic premise behind rock climbing is extremely simple. The climber is trying to climb from the bottom to the top of something. If that was all there were to it, then the climber would need nothing but his or her body and a good pair of climbing shoes. However, safety issues arise in the sport if the climber slips anywhere along the way. Because of the possibility of falling, rock climbing involves a great deal of highly specialized equipment to catch climbers when they fall.
[0004] Part of the specialized equipment includes climbing holds. Climbing holds are grabbed and stepped on by a climber in order to ascend the wall. It is important for the holds to be rigidly secured to the climbing wall in order to prevent the hold from moving under the weight of a climber. Also, climbing holds come in a variety of configurations in order to simulate movement patterns in climbing. Such holds are typically formed of synthetic material such as a polyester resin, which gives hold a rough texture.
[0005] There are two conventional types of climbing walls that are used to simulate rock climbing activity. The first type of climbing wall includes a substantially vertical climbing surface that has a rock like texture (See e.g. U.S. Pat. No. 5,254,058 to Savigny, “Artificial climbing wall with modular rough surface”, Oct. 19, 1993). The shape or texture of the climbing wall determines the level of difficulty associated with maneuvering around this type of climbing wall. The second type of climbing wall includes rock-like hand and foot holds that are attached to a normal (i.e., substantially smooth) wall (See e.g. U.S. Pat. No. 5,125,877 to Brewer, “Simulated climbing wall,” Jun. 30, 1992). There are two ways to adjust the level of difficulty associated with maneuvering about this type of climbing wall. First, the location of the holds on the wall vary according the level of skill of a particular climber. Second, the shape of the individual holds can be modified in order to make them easier or more difficult to grasp.
[0006] Using artificial climbing walls to simulate outdoor rock climbing activity is well known. Artificial climbing walls provide rock-climbing enthusiasts with the opportunity to simulate outdoor rock climbing activity at an easily accessible location. The climbing holds are normally attached to a wall using bolts or threaded rods. The climbing holds are typically of varying shapes and textures that affect the level of skill required to maneuver on the climbing wall. In particular, climbing walls that have a minimal number of holds are harder to grasp and make the wall harder to negotiate. Another factor affecting the level of skill required to maneuver on the climbing wall is the position of the climbing holds on the climbing wall. The closer the climbing holds are positioned relative to one another, the more climbing holds there are available for grasping by a climber as the climber maneuvers on the climbing wall.
[0007] Prior art climbing holds present significant problems when attempting to properly secure them to a climbing wall. Climbing holds typically have an aperture extending therethrough in order to permit a bolt to extend and threadably engage the climbing wall. The bolt is tightened to secure the climbing hold to the wall and prevent the hold from either transitional or rotational movement. In order to ensure that the hold does not rotate, a bolt must be tightened to a certain torque such that the hold is tight against the wall and prevented from rotating by the frictional force existing between the planar mounting face of the hold and the opposing portion of the climbing wall. However, in attempting to prevent the climbing hold from moving, the bolt may be over tightened resulting in the molded body of the climbing hold to fracture. The head of the bolt upon engaging the upper body portion of the climbing hold creates an area of high stress concentration adjacent to the bolt head making the hold susceptible to cracking about this area. Accordingly, a narrowly acceptable range of torque results in order to ensure that the climbing hold is properly secured but not damaged. Fracture of the hold may lead to the hold falling from the wall upon being stressed by the weight of a climber. Since a climber may place all of their weight on a particular hold, its breaking may result in a fall that could injure the climber. Known climbing holds have some limits and drawbacks. In fact, when holds are applied to and integrated into the climbing wall, the same are substantially fixed as regards positions, number and conformation, and substantially do not enable the climbing situations and problems to be changed in order to modify the degree of technical difficulty in climbing, unless specialized interventions and/or rearrangements involving manipulations are carried out. In addition, it should be noted that known climbing holds are heavy and of difficult, expensive and unquick construction.
[0008] Another problem associated with a climbing hold is that it has a tendency to loosen as climbers use it. Depending on how a climber grasps the climbing hold, the climber may generate a torque on the hold which could rotate (i.e., loosen) the hold from the climbing wall. The present invention overcomes this and other problems associated with the prior art.
SUMMARY OF THE INVENTION
[0009] A wall-climbing accessory adapted for mounting onto a wall structure is described. The wall-climbing accessory comprises a resilient body that is flexible such that the resilient body may deform when mounted to a wall structure. The resilient body comprises an exterior surface and an edge. The exterior surface is configured and arranged to provide an engagement point capable of supporting a climber of the wall structure, whereby a climber may scale a wall structure by using the wall-climbing accessory. The edge is configured to substantially engage the wall structure such that, when affixed, the resilient body and edge impart a torsion force to the wall structure such that a flexible, friction fit is formed between the wall-climbing accessory and the wall structure. The wall-climbing accessory uses only one primary fastener to attach to the wall structure and thus is less prone to rotation than prior art climbing holds. Additional screws may be added to a periphery of the wall-climbing accessories for extra protection against rotation. Furthermore, the resilient body is flexible and lighter when compared to prior art climbing holds. Additional advantages and features of the invention will be set forth in part in the description that 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.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a cross sectional view of a prior art climbing hold.
[0011] FIG. 2 is a perspective view of wall climbing accessories mounted on a wall structure and in use by a climber.
[0012] FIG. 3 is a front-elevation view of the wall-climbing accessory.
[0013] FIG. 4 is a section cut along line 4 - 4 of FIG. 3 of the wall-climbing accessory.
[0014] FIG. 5 is a section cut along line 5 - 5 of FIG. 3 of the wall-climbing accessory.
[0015] FIG. 5 a is a section similar to FIG. 5 of the wall-climbing accessory, in tension.
[0016] FIG. 6 is a front elevation view of a second version of the wall-climbing accessory mounted and in use.
[0017] FIG. 7 is a cross sectional view of the second version of the wall-climbing accessory taken along lines 7 - 7 of FIG. 6 , mounted and in use.
[0018] FIG. 8 is a front elevation view of the wall-climbing accessory, mounted, rotated 90 degrees from the original position in FIG. 6 , and in use.
DETAILED DESCRIPTION
[0019] FIG. 1 is a cross-sectional view of a prior art climbing hold 101 . Prior art climbing holds 101 are heavier, take up more volume, and are more rigid than applicant's wall climbing accessory 100 . Furthermore, some prior art climbing holds 101 are solid. Therefore, those prior art climbing holds 101 are extremely heavy and rigid. In addition, it is worth noting that prior art climbing holds 101 often utilize more than one fastener to secure the hold to a wall. For purposes of this explanation, a wall-climbing accessory 100 is a type of climbing hold.
[0020] FIG. 2 is a perspective view of wall climbing accessories 100 mounted on a wall structure 102 in use by a climber C. Several wall-climbing accessories 100 are variably mounted to a wall structure 102 . It will be appreciated by those skilled in the art that during construction, the wall structure 102 is made first, the wall climbing accessories 100 are mounted to the wall structure 102 second. In preferred embodiments, the wall structure 102 is made from plywood with a concrete coating. However, it will be appreciated by those skilled in the art that the wall structure 102 may be made from a polymer such as roto-molded polyethylene panels, PVC, or PMA. It will also be appreciated by those skilled in the art that the wall structure 102 may be made from solid concrete. The wall structure 102 may also be made with a combination of polymer and concrete, or various materials known in the art. The problems associated with rotating prior art climbing holds 101 are more severe in polymer and solid concrete walls due to slippery and uneven surfaces. It will also be appreciated by those skilled in the art that t-nuts 119 are installed or threaded through from the back of the wall structure 102 . The wall-climbing accessory 100 is installed onto the t-nut 119 via a fastener, or bolt 118 . One advantage of the wall-climbing accessory 100 is that it is easy to install and uninstall to provide a variety of grips on the wall structure 102 because only one fastener is necessary to hold the wall-climbing accessory 100 to the wall structure 102 . It will be appreciated by those skilled in the art that route setters change the position of the wall climbing accessories 100 frequently. Prior art climbing holds 101 utilize multiple fasteners to affix to the wall structure 102 , making it difficult to change the position of the climbing hold quickly.
[0021] FIG. 3 is a front-elevation view of the wall-climbing accessory 100 . 121 are phantom depictions of optional locations for recessed fastener openings 114 . A resilient body 104 of the wall-climbing accessory 100 has an exterior surface 106 and an edge 112 . It will be understood by those skilled in the art that a washer or other load distributing device may be embedded into the recessed fastener opening 114 during assembly of the wall climbing accessory 100 for stress concentration purposes. The wall-climbing accessory 100 is less brittle than the prior art 101 due to a different means of manufacturing the apparatus. Commonly, the prior art method uses a silicon mold that is filled with liquid material that cures and hardens into the final product. In some prior art methods, plugs are used during the casting process to make the climbing hold hollow for reducing weight. However, these climbing holds remain heavy and rigid. The new manufacturing process can utilize either a spray on technique or injection mold process. Plugs are no longer needed. It is important to note that in preferred alternative embodiments, the wall-climbing accessory 100 may also be made from overlaying patches of fiber-reinforced mesh. In the preferred embodiments of spray on technique or injection mold, a piece of equipment known as a chopper gun is used. The matrix material, generally polyester resin and glass fiber, is sprayed onto the mold at the same time. The matrix material covers the glass fibers while the material is being sprayed and the resulting composite is then consolidated by hand using rollers and paintbrushes. This process is inexpensive and requires no special tooling. The outer coat of the wall climbing accessory 100 consists of a colored material (gel coat) and the inner coat is random, discontinuous strands of fiberglass resin. It will be understood by those skilled in the art that any fiber-reinforced polymer can be substituted. However, in preferred embodiments fiberglass resin is used.
[0022] There is a greater percentage of glass fibers in the wall climbing accessory 100 than in prior art climbing holds 101 . Prior art climbing holds 101 , which are not easily deformed (not flexible) typically have a ratio of 2% glass fibers to 98% polyester resin and fillers. This makes the prior art climbing holds 101 heavy, non-resilient, and stiff. The wall-climbing accessory 100 is composed of approximately 50% glass fibers and 50% fiber reinforced polymers or polyester resin. Consequently, the wall-climbing accessory 100 is less prone to breakage and is flexible. Moreover, the wall climbing accessory 100 is resilient and forgiving of the climber's C, grip during climbing.
[0023] FIG. 4 is a section cut along line 4 - 4 of FIG. 3 of the wall-climbing accessory 100 . A cavity 116 , which is defined by the resilient body 104 , is shown. The resilient body 104 has extra flexible properties as compared to the prior art holds 101 . Furthermore, cavity 116 in the resilient body 104 is larger than the cavities in prior art 101 thereby making the wall climbing accessory 100 lighter as compared to prior art climbing wall holds 101 . Another feature of the wall climbing accessory 100 is that due to its lighter weight than prior art handholds 101 , it is easier to carry up the wall structure 102 for installation purposes. This is safer for hauling climbing holds up and down wall structures 102 .
[0024] Furthermore, the edge 112 that is formed along the resilient body 104 is capable of flexing and forming to a wall structure 102 that may be textured, contoured, or featured surface. The edge 112 is an engaging perimeter, which frictionally engages the wall structure 102 . The reverse sides of prior art climbing holds 101 are generally planar, causing more rotation and slippage.
[0025] FIG. 5 is a section cut along line 5 - 5 of FIG. 3 of the wall-climbing accessory 100 . The wall-climbing accessory 100 has a bolt 118 inserted through a recessed fastener opening 114 . The bolt 118 is inserted through the recessed fastener opening 114 as a means to attach the resilient body 104 to the t-nut 119 in the wall structure 102 . A washer helps prevent the bolt 118 from damaging or cracking the resilient body 104 during installation. It will be appreciated by those skilled in the art that the recessed fastener opening 114 need not be recessed, it may be level to or protruding above the exterior surface 106 . In addition, it will also be appreciated by those skilled in the art that the t-nut 119 and bolt 118 may be interchanged with pop rivets, screws, nails, and standard nut and bolt arrangements. Some varieties of the standard nut and bolt arrangement include but are not limited to socket head cap-screws, hex head bolts, button head cap-screws, or flat head cap-screws.
[0026] FIG. 5 a is a section similar to FIG. 5 of the wall-climbing accessory 100 , in tension. The bolt 118 is tightened to the t-nut 119 . The edge 112 frictionally engages the wall structure 102 , causing a torqued fit of the resilient body 104 . The wall-climbing accessory 100 will not shift if gripped by a climber C. Another advantage of the wall-climbing accessory 100 is that it does not have a tendency to rotate around the bolt 118 . More surface opening than prior art climbing holds 101 make the wall climbing accessory 100 more anti-rotation. Less surface area engages the wall structure 102 , thereby giving more force and grip to the wall. The prior art climbing holds 101 have smaller cavities and are thus less hollow. Therefore, more flat surface area engages the wall structure 102 , thereby increasing the likelihood of rotation. Prior art climbing holds 101 are stiff and unyielding and present a large, smooth area of contact against the wall surface which then lends itself to rotational motion of the hold due to its stiff and unyielding qualities. However, the wall-climbing accessory 100 has the ability to deform and thus “dig in” to the surface of wall structure 102 .
[0027] FIG. 6 is a front elevation view of a second version of the wall-climbing accessory 100 mounted and in use. A hand 120 is shown in phantom to give an example of where a rock climber C may grip the exterior surface 106 . Furthermore, in preferred embodiments the resilient body 104 may have an additional modular accessory 122 protruding from the exterior surface 106 for purposes of providing variety of grip to the climber C. The additional modular accessory 122 is constructed from material similar to the wall-climbing accessory 100 . The additional modular accessory 122 is typically mounted on flat spots and cross sections of the wall-climbing accessory 100 . In preferred embodiments the additional modular accessory 122 is fastened to the exterior surface 106 via a fastener similar to the t-nut 119 and bolt 118 system that extends to the wall structure 102 . In alternative preferred embodiments the additional modular accessory 122 is mounted only to the exterior surface 106 via a fastener similar to the t-nut 119 and bolt 118 system. In the alternative preferred embodiment, the t-nut 119 and bolt 118 does not extend to the wall structure 102 .
[0028] FIG. 7 is a cross sectional view of the second version of the wall-climbing accessory 100 taken along lines 7 - 7 of FIG. 6 , mounted and in use.
[0029] FIG. 8 is a front elevation view of the wall-climbing accessory 100 a , mounted, rotated 90 degrees from the original position in FIG. 6 , and in use. FIG. 8 shows the same wall-climbing accessory 100 of FIG. 6 rotated 90 degrees and secured via the bolt 118 in the recessed fastener opening 114 . This provides a variety of grips for the climber C and also aids in increasing the challenge of a competition. It will be appreciated by those skilled in the art that the wall climbing accessory 100 may be rotated greater than or less than 90 degrees.
[0030] It will be appreciated by those skilled in the art that the wall-climbing accessory 100 may have a ridge, rib, or bridge that engage the wall structure 102 in addition to or alternative to the edge 112 . Also, the wall-climbing accessory 100 may be toroid shaped or be other shapes that have holes formed therethrough. Furthermore, the wall-climbing accessory 100 may have more than one recessed fastener opening 114 and bolt 118 affixing the apparatus to the wall structure 102 , as seen in phantom in FIGS. 3 and 8 . However, in preferred embodiments only one central fastener is necessary to affix the apparatus to the wall structure 102 because of the friction fit formed by the resilient body 104 and edge 112 .
[0031] Moreover, the wall-climbing accessory 100 may have an irregular exterior surface 106 for simulating a natural rock structure. The exterior surface 106 may also have identifying insignia or marks for aesthetic or competition purposes. In addition, an asymmetrical sidewall or walls may be included into the resilient body 104 . Another advantage of the wall-climbing accessory 100 is that each apparatus of the same shape has the same hollowed out portion, therefore the accessories may be stacked, or nested, together for ease in carrying and shipping.
[0032] It is to be understood that even though numerous characteristics and advantages of various embodiments of the present invention have been set forth in the foregoing description, together with details of the structure and function of various embodiments of the invention, this disclosure is illustrative only, and changes may be made in detail, especially in matters of structure and arrangement of parts within the principles of the present invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | A wall-climbing accessory adapted for mounting onto a wall structure is described. The wall-climbing accessory comprises a resilient body that is flexible. The resilient body comprises an exterior surface and an edge. The exterior surface is configured to provide an engagement point capable of supporting a climber of the wall structure, whereby a climber may scale a wall structure by using the wall-climbing accessory. The edge is configured to substantially engage the wall structure such that, when affixed, the resilient body and edge impart a torsion force to the wall structure such that a flexible, friction fit is formed between the wall-climbing accessory and the wall structure. The wall-climbing accessory use only one primary fastener to attach to the wall structure and thus is less prone to rotation than prior art climbing holds. Furthermore, the resilient body is flexible and lighter when compared to prior art climbing holds. | 0 |
BACKGROUND OF INVENTION
[0001] This invention relates to crayons and, more particularly, to crayons having at least three generally planar exterior surfaces and transverse cross-sections containing multiple zones of color, and associated packaging.
[0002] There are many examples of writing implements that allow for multiple marking elements, each with a different color, to be housed in the same implement. Examples include pencils with a different colored point at each end, pens containing multiple ink cartridges containing different colored inks whose points can be extended and used at will, and crayons having a transverse circular cross-section with multiple colors radiating outwardly from and running along a centrally disposed longitudinal axis, where the colors are generally transversely equally disposed through the cross section.
[0003] Circular crayons containing multiple color zones, however, do not allow for easy, discreet use of the individual colors. As the number of colors in the crayon increases, the exposed surface area of each color decreases. Attempting to press the correct part of the small, curved surface of a round crayon at the correct angle to a surface may be difficult, particularly for young children. Typically, the result of using a round crayon having multiple colors running along a centrally disposed longitudinal axis is an unintentional and unwanted mix of colors, especially when manufacture of these types of crayons result in non-uniform color disbursement through the color zones of the crayon.
[0004] Crayons with cylindrical shanks also have the problem of being difficult to handle, and not readily or reliably indexable. Other shapes have been used that are more ergonomic, such as shapes having a triangular or hexagonal transverse cross-section. A further benefit of some of these non-cylindrical instruments that they do not roll as easily. There are some non-cylindrical writing implements that contain multiple colors, including crayons.
[0005] When dealing with crayons or other writing implements having transverse cross-sections of shapes other than circles, for example, triangles, rectangles, and so forth, containing multiple colors, the color zones interface along the lines bisecting vertices between interior surfaces. For example, when looking at a transverse cross-section of a triangular crayon containing three colors, the individual colors form isosceles triangles, with the vertex of the obtuse angle of each color meeting in the center of the cross-section. The three vertices of the transverse cross-section of the crayon will each be bisected by the interface of two color zones. Thus, it can be extremely difficult to use an individual color in a configuration such as this, because each vertex, as well as the point of the crayon, is composed of multiple colors.
[0006] Crayons with a round transverse cross-section are also an inefficiently packaged product. When placing cylindrical objects into a container with a rectangular transverse cross-section, there is a large amount of interstitial space. Even placing crayons with a transverse cross-section of an equilateral triangle into a container with a rectangular transverse cross-section creates interstitial space, though less than with cylindrical crayons. Also, stacking packages with rectangular transverse cross-sections can result in unstable stacks. Just as bricks are staggered when a building is constructed (bricking), so should rectangular packages of crayons. In some locations where the stacking of packages is utilized, such as in a store selling the packages of crayons, not bricking the packages could result in fallen stacks. Bricking takes quite a bit of time for planning and execution; it is slow; and it is thus costly.
[0007] Accordingly, a need remains for an improved design for crayons or other writing instruments, such as chalk, containing multiple colors, and improved packaging that can efficiently contain the crayons without being unstable when stacked.
SUMMARY OF INVENTION
[0008] The invention involves the provision of an elongate crayon having a wax-like core and a paper-like reinforcing outer cover (where wax-like includes wax and paper-like includes paper) with a transverse cross-section having at least three side surfaces, such as an equilateral triangle, a rectangle, a pentagon, or a hexagon, preferably having side surfaces of equal lengths and vertices of equal angles between adjacent side surfaces. The longitudinal side surfaces of the shank are generally planar. Further, for regular shapes, the crayon can contain the same number of colors as the transverse cross-section has vertices, such that each color zone forms a polygon in the form of a quadrilateral kite, a shape having two pairs of sides with each pair having of generally equal length (in the case of a transverse cross-sectional square, the kite formed by each color zone would, in fact, be a square). For example, when dealing with a crayon with an equilaterally triangular transverse cross-section, the two exposed surfaces of each kite would generally be of equal transverse length, and the two interface surfaces of each kite would generally be the same transverse length.
[0009] In the transverse cross-section, each color zone would have four vertices. For a triangular cross-sectional crayon, the central 120° angle of a color zone would be formed at the center of the cross-section by the connection of two color zone interfaces. Two opposing angles in the color zone are 90°, each of which is formed by bisecting adjacent faces of the cross-section with the color zone interfaces. The two adjacent outer surfaces connect to form the final 60° angle of the kite. Since each of these kites is a separate zone of color, and since each of these kites has a vertex formed at the intersection of two adjacent outer surfaces, each color can be easily and advantageously used on its own by marking with the distal end of the shank or with the tapered portion adjacent the shank, without accidentally encroaching on adjacent color zones, and may be readily indexed for use. The crayon may also be used to blend colors by using the point to mark. Other cross-sectional shapes are similarly constructed, but will yield different included angles.
[0010] Also, the present invention relates to the associated packaging for crayons having transverse cross-sections of a triangle. This type of packaging would waste nearly zero space, as the interstitial space would be greatly reduced to nearly nothing. Such packaging would be elongate as the crayons themselves are elongate, and could have transverse cross-sectional shapes of equilateral triangles, regular trapezoids, regular parallelograms, regular hexagons, and so forth. For example, with packaging having a transverse cross-sectional shape of an equilateral triangle, crayons would be longitudinally inserted into the packaging chamber, and could be packaged in numbers N i of:
N 1 =1, N 2 =4, N 3 =9, N 4 =16, . . . , where N i =N i−1 +[(2× i )−1], where i= 1 . . . ∞
which numbers of crayons allow for the packages to have transverse cross-sections of equilateral triangles. Packing crayons in these numbers in an overall shape having a transverse cross-section of an equilateral triangle, where the crayons to be packaged have a transverse cross-section of an equilateral triangle, advantageously reduces the interstitial space and allows for easier and more stable stacking of the packages, as long as the packages are stacked in the same manner as the crayons are packaged.
BRIEF DESCRIPTION OF DRAWINGS
[0011] For a better understanding of the present invention, reference may be made to the accompanying drawings.
[0012] FIG. 1 is a side elevational view of a crayon having a triangular transverse cross-section.
[0013] FIG. 2 is an end elevational view of the crayon shown in FIG. 1 , as viewed from the right hand end of FIG. 1 .
[0014] FIG. 3 is a transverse cross-sectional view of the crayon shown in FIG. 1 , taken along line 3 - 3 .
[0015] FIG. 4 is a transverse cross-sectional view of a crayon with a transverse cross-section of a square.
[0016] FIG. 5 is a transverse cross-sectional view of a crayon with a transverse cross-section of a regular pentagon.
[0017] FIG. 6 is a transverse cross-sectional view of a crayon with a transverse cross-section of a regular hexagon.
[0018] FIG. 7 is a perspective view showing packaging associated with triangular transverse cross-sectional crayons.
[0019] FIG. 8 is a transverse cross-sectional view of boxes having rectangular transverse cross-sections, which contain crayons having circular transverse cross-sections, taken through the shanks of the crayons.
[0020] FIG. 9 is a transverse cross-sectional view of boxes having rectangular transverse cross-sections, which contain crayons having equilateral triangular transverse cross-sections, taken through the shanks of the crayons.
[0021] FIG. 10 is a transverse cross-sectional view of a larger box having a rectangular transverse cross-section, which contains crayons having equilateral triangular transverse cross-sections, taken through the shanks of the crayons.
[0022] FIG. 11 is a transverse cross-sectional view of packaging with a transverse cross-section of an equilateral triangle, taken along line 11 - 11 in FIG. 7 .
DETAILED DESCRIPTION
[0023] According to the embodiment(s) of the present structures, various views are illustrated in FIGS. 1-11 and like reference numerals are used throughout to refer to like or similar parts or construction for the various views and Figures.
[0024] One embodiment of the present invention comprises multicolored elongate crayons 10 with transverse cross-sectional shapes having at least three generally planar sides wherein the color zones 31 ( FIG. 3 ), 41 ( FIG. 4 ), 51 ( FIG. 5 ), and 61 ( FIG. 6 ) meet at interfaces 36 positioned at approximately 90° angles to each of the external surfaces 32 (A-C) ( FIG. 3 ), 42 (A-D) ( FIG. 4 ), 52 (A-E) ( FIG. 5 ), and 62 (A-F) ( FIG. 6 ) of the transverse cross-section as opposed to at the vertices 35 (A-C) ( FIG. 3 ), 45 (A-D) ( FIG. 4 ), 55 (A-E) ( FIG. 5 ), and 65 (A-F) ( FIG. 6 ) of the transverse cross-section. Similarly shaped packaging 70 for crayons 10 can be provided which are shown in FIGS. 7 and 11 as having transverse cross-sections of equilateral triangles.
[0025] The details of the invention and various embodiments can be better understood by referring to the Figures of the drawings. Referring to FIGS. 1-2 , one embodiment includes an elongate crayon 10 , with a shank 11 having a distal end 14 and a proximal end 13 , and a wax-like, non-liquid core encompassed in a paper-like outer cover 17 . The crayon 10 further has an end portion tip 12 axially extending from the proximal end 13 of the shank 11 , tapering from the proximal end 15 of the tip 12 to the distal end 16 of the tip 12 adapted for engaging and marking a writing surface. The tip 12 tapers inwardly toward the central axis of the crayon 10 from the end 15 to the end 16 . Referring to FIG. 2 , the tapering end portion 12 is shown as having a transverse cross-section of an equilateral triangle, where all three major external surfaces 21 A-C of the end portion 12 are, before use, generally planar and the same size and shape having vertices 25 A-C between the outer surfaces 21 A-C. However, the converging end portion 12 can have a transverse cross-section of other shapes than that shown in FIGS. 1-3 , depending on the transverse shape of the shank 11 . The shank 11 includes at least three major generally planar longitudinal outer surfaces which are shown as surfaces 32 A-C joined at vertices 35 A-C for a triangular crayon.
[0026] Referring to FIGS. 3-6 , such crayons further have transverse cross-sections of preferably regular shapes wherein all external side surfaces are of generally equal width and length and all vertices 35 , 45 , 55 , 65 , e.g., 35 A-C, are of generally equal angles; and where all surfaces for a crayon 10 are equidistantly spaced from a centrally disposed longitudinal axis. Such crayons also have a plurality of separate color zones 31 , 41 , 51 , 61 , e.g. 31 A-C, equal to the number of vertices in the transverse cross-section of the crayon 10 at the shank 11 .
[0027] The crayon 10 ( FIGS. 1-3 ) has a triangular transverse cross-section containing three color zones 31 A-C, each of which form the shape of a polygon with at least four sides (quadrilateral) or kite such that the central 120° angle B of each color zone 31 , for example color zone 31 C, would be formed at the center of the cross-section by the interface 36 between two color zones 31 . Preferably, the color zones 31 A-C are similarly sized and shaped in transverse cross section. Two opposite angles A in a color zone 31 , e.g. color zone 31 C are 90°, each of which would be formed by bisecting adjacent outer surfaces 32 B, 32 C of the cross-section with the color zone interfaces 36 . Preferably, the interfaces 36 are generally planar. The two adjacent outer surfaces 32 B, 32 C are illustrated as connected at the vertex 35 C to form the final 60° angle C of the kite shaped color zone 31 C. The vertices 35 A, B also have an angle C of 60°. The vertices 35 A-C are formed at the corners between the surfaces 32 A-C.
[0028] The crayon 40 ( FIG. 4 ) has a rectangular and preferably square transverse cross-section containing four color zones 41 A-D, each of which form the shape of a polygon with at least four sides (quadrilateral) or kite (which, in the illustrated form, is also a square) such that the central 90° angles D of a color zone 41 , for example color zone 41 A, would be formed at the center of the rectangle by the interface 36 between two color zones. Two angles E in each color zone, e.g., color zone 41 A are 90°, each of which would be formed by bisecting adjacent outer surfaces 42 A, 42 B of the cross-section with the color zone interfaces 36 . The two adjacent outer surfaces 42 A, 42 B are illustrated as connected at the vertex 45 A to form the final 90° angle F of the illustrated kite shaped rectangle and preferably the other color zones 41 B-D are similarly constructed to square color zone 41 A. The other color zones 41 B-D are similarly constructed by the surfaces 42 A-D and vertices 45 B, C, D. The color zones 41 A-D are preferably similarly sized and shaped in transverse cross section.
[0029] The crayon 50 ( FIG. 5 ) has a regular pentagonal transverse cross-section containing five color zones 51 A-E, each of which form the shape of a polygon of at least four sides (quadrilateral) or kite such that the central 72° angle G of a color zone 51 , for example color zone 51 A, would be formed at the center of the pentagon by the adjoining interfaces 36 of three color zones 51 E, A, B. Two opposite angles H in the color zone 51 A are 90°, each of which would be formed by bisecting adjacent outer surfaces 52 A, 52 E of the cross-section with the color zone interfaces 36 . The two adjacent outer surfaces 52 A, 52 E are illustrated as connected at vertex 55 A to form the final 108° angle I of the kite shaped color zone 51 A. The other color zones 51 B-E are similarly constructed with the surfaces 52 A-E and vertices 55 B-E. The color zones 51 A-E are preferably similarly sized and shaped in transverse cross section.
[0030] The crayon 60 ( FIG. 6 ) has a regular hexagonal transverse cross-section containing six color zones 61 A-F, each of which form the shape of a quadrilateral or kite such that the central 60° angle J of a color zone 61 , for example color zone 61 A, would be formed at the center of the hexagon by two adjoining interfaces 36 between color zones. Two angles K in the color zone 61 A would be 90°, each of which would be formed by bisecting adjacent outer surfaces 62 A, 62 B of the cross-section with the color zone interfaces 36 . The two adjacent outer surfaces 62 A, 62 B are illustrated as connected at vertex 65 A to form the final 120° angle L of the kite shaped color zone 61 A. The other color zones 61 B-F are similarly constructed with the surfaces 62 A-F and vertices 65 B-F. The color zones 61 A-F are preferably similarly sized and shaped in transverse cross section.
[0031] Referring to FIG. 7 , the package 70 associated with the crayons 10 above is an elongate container, similar in longitudinal length to the above described crayons and with a triangular transverse cross-section for use with the triangular cross-section crayon. Such container includes longitudinal panels 71 and end closures 72 , 73 with end closure 73 being constructed for selectively closing one end 74 of the package 70 and bottom end closure 72 normally closing the other end of the package 70 . The panels 71 and end closures 72 , 73 define a storage compartment. The closure 73 is shown as a hinged flap that is triangular in shape and is attached along a hinge edge 75 of the closure 73 to one edge of the open end 74 of the container 70 , such that said closure 73 can be folded to cover and close the open end 74 of the container. In addition, in order to secure the closure 73 in the closed position, a secondary generally rectangular flap 76 is attached at one of it's edges to one of the two free edges of the closure 73 such that when the closure 73 is folded into the closed position, the secondary rectangular flap 76 folds down into the open end 74 of the container selectively holding the closure 73 closed.
[0032] Referring to FIGS. 8-11 , transverse cross-sectional views of various packages having different transverse cross-sections and containing crayons 10 are shown. Packing densities in the storage compartment in the container, defined as the area of the transverse cross-sectional area of the crayons at their shank divided by the total inside area of the transverse cross-section of the package, are much more efficient for crayons, packaged in numbers of four or more, having transverse triangular cross-sections than those with transverse circular cross-sections. In order to most efficiently fit a single cylindrical crayon 81 into a box 80 I with a rectangular transverse cross-section, that cross-section should have sides 82 equal to the diameter of the circular transverse cross-section of the shank of crayon 81 . This most efficient manner of packing a cylindrical crayon 81 into a box 80 I with a rectangular transverse cross-section results in a packing density of 0.785, and thus 78.5% of the rectangular transverse cross-section of the package 80 I is occupied by the cross-section of the crayon 81 . Similarly, when efficiently packaging two or more cylindrical crayons 83 into a box 80 II with a rectangular transverse cross-section, the width 84 of the box 80 II should equal the diameter of the circular transverse cross-section of the crayons 83 multiplied by the number of columns of crayons 83 to be packaged, and the height 85 of the box 80 II should equal the diameter of the circular transverse cross-section of the crayons 83 multiplied by the number of rows of crayons 83 to be packaged. Therefore, because each cylindrical crayon 83 is packaged in the same amount of space as is the individually packaged cylindrical crayon 81 above, the packing density will always be 0.785, and thus 78.5% of any box with a rectangular cross-section will be occupied by the transverse cross-section of cylindrical crayons when the crayons are packaged most efficiently.
[0033] However, when packaged most efficiently, the packing density of crayons with transverse cross-sections of equilateral triangles is not always the same. Referring to FIG. 9 , when a single crayon 91 with a transverse cross-section of an equilateral triangle is most efficiently packaged in a box 90 I with a rectangular transverse cross-section, half of the package's transverse cross-section is interstitial space 92 . However, when two crayons 93 with transverse cross-sections of equilateral triangles are most efficiently packaged in a box 90 II with a rectangular transverse cross-section, a third crayon 94 with a transverse cross-section of an equilateral triangle can be packaged in the interstitial space between the original two crayons 93 . In this case, only one quarter of the package's transverse cross-section is interstitial space 95 . When three crayons 96 with transverse cross-sections of equilateral triangles are most efficiently packaged in a box 90 III with a rectangular transverse cross-section, a fourth and fifth crayon 97 with transverse cross-sections of equilateral triangles can be packaged in the interstitial space between the original three crayons 96 . In this case, about 83.3% of the package's transverse cross-section is occupied, and only one-sixth of the package is interstitial space 98 . Similarly, referring to FIG. 10 , when packaging ninety two crayons with transverse cross-sections of equilateral triangles in four rows of twenty three crayons, the packing density rises to about 0.96, and thus 96% of the transverse cross-section of the rectangular box 100 is occupied and only about 4% is interstitial space 104 . Therefore, as more crayons with equilaterally triangular transverse cross-sections are packaged in such a way as to allow extra equilaterally triangular transverse cross-sectional crayons 103 to be inserted into the interstitial space between crayons 102 , the packing density rises and the space in the package is more efficiently used. The packing density is preferably at least about 0.9 and more preferably about 1.0. Indeed, as can be seen in FIG. 11 , when crayons of equilaterally triangular transverse cross-sections 111 are packaged in an elongate package with an equilaterally triangular transverse cross-section, such as is seen in FIG. 7 , there is nearly no interstitial space in the package 110 . It follows that when crayons of generally rectangular transverse cross-section are packaged in an elongate package with a similarly generally rectangular transverse cross-section, there is similarly nearly no interstitial space.
[0034] The various multicolored transverse cross-sectionally shaped crayons and the packaging containers associated therewith shown above illustrate a novel crayon and associated packaging. A user of a multicolored crayon may color using any of the plurality of vertices 25 A-C ( FIG. 2 ), 35 A-C ( FIG. 3 ), 45 A-D ( FIG. 4 ), 55 A-E ( FIG. 5 ), 65 A-F ( FIG. 6 ) on the crayon without accidentally using unwanted colors. A crayon may be used to provide blended colors by marking with the end 16 of tip 12 . In this regard, the tip or point 12 will provide a rainbow effect of the multiple colors. Marking with distinct, separate colors may be done by applying any of the vertices between adjacent outer surfaces at either the tip 12 or the shank 11 at or between the proximal end 13 or distal end 14 of the shank. Marking with each vertice individually provides a separate distinct color thereby effectively giving the user a plurality of single color crayons in one writing instrument. This can be extremely advantageous to a restaurant owner/operator, for example, because the restaurant owner would be able to enjoy a cost savings on their expenditures for crayons by giving away only one of the multicolored crayons, as compared to a package of three or more crayons each with a different color.
[0035] While the vertices 25 , 35 , 45 , 55 , 65 are shown as sharp points, it is recognized and anticipated that they can be initially curved or flat which might be considered to be a fifth surface for the polygon but still form a vertex wherein the cross-sectional shapes are still as described above. Also, a user of the packaged polygonal crayons, as described above, may make use of most all available space inside the package and may stack the packages more efficiently and effectively. In this regard, it is recognized that various forms of the subject various multicolored or single color transverse cross-sectionally shaped crayons and the triangular or other polygonal packaging container, e.g., rectangular, associated with a triangularly or rectangularly transverse cross-sectional crayon could be utilized without departing from the spirit and scope of the present invention. Still further, triangularly or rectangularly shaped packaging containers pack nicely into bulk containers or boxes and, in the case of triangular containers, such containers themselves can interlock with each other and improve the packing volume efficiencies as explained above.
[0036] Thus, there has been shown and described several embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. The terms “having” and “including” and similar terms as used in the foregoing specification are used in the sense of “optional” or “may include” and not as “required”. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. | A crayon with a plurality of longitudinally extending color zones. The crayon has generally planar exterior side surfaces on the tip and shank forming vertices therebetween. A color zone bridges a vertex providing the same color of marking material on opposite sides of a respective vertex. | 2 |
TECHNICAL FIELD
The present invention relates to load suspension in wheeled vehicles, and more particularly to a vehicle load coupling apparatus that reduces the effort required to move the vehicle and its load.
BACKGROUND OF THE INVENTION
The conventional approach to movement of a load by a wheeled vehicle, whether by road or rail, is to place the full weight of the load (including the vehicle frame and engine, if any) directly on the wheel axles. Although suspension system components such as springs and dampers are often used to isolate the load from the axle, the load and the various components of the vehicle are moved in unison in the direction of travel. This means that the motive power source, whether in the form of an internal combustion engine, an electric or hydraulic motor, or even manual labor, must expend sufficient energy to initiate movement of the entire weight of the vehicle and load. Various efforts have been made in the transportation industry to improve energy conversion efficiency and reduce frictional losses such as rolling resistance, but the improvements continue to be incremental in nature, and the overall rates of fuel consumption and combustion emission production remain unacceptably high. Accordingly, what is needed is a way of moving wheeled vehicles and their loads with reduced effort, leading to corresponding reductions in fuel consumption and combustion emission production.
SUMMARY OF THE INVENTION
The present invention provides a new and improved load coupling apparatus for coupling loads to the wheels of a wheeled vehicle. Fundamentally, the invention involves the use of load linkage members for pivotally suspending the load weight below the axles or center-points of the wheels, allowing limited relative displacement of the wheels and the load in the direction of vehicle travel. The load is displaced by moving the vehicle wheels in the desired direction of travel, whereafter the suspended load follows the wheels in a swinging motion as the effects of gravity overcome the load inertia. The effort required to initiate movement of the load is significantly reduced due to the relative displacement of the wheels and the load, and the mechanical advantage afforded by the load linkage members. Once in motion, the load continues to track the wheels in the direction of travel, providing continued reduction in motive effort even when the load reaches a constant forward speed. Dampers can be employed to control forward shifting of the load when the wheels are decelerated during braking. The apparatus can be applied to any wheeled vehicle, including manually operated vehicles, self-propelled vehicles, and trailered vehicles.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIGS. 1A and 1B diagrammatically depict the axle of a trailered vehicle equipped with a load coupling apparatus according to a first embodiment of this invention. FIG. 1A presents an end or longitudinal view, while FIG. 1B presents a side or lateral view illustrating the operation of the load coupling apparatus of FIG. 1A .
FIGS. 2A and 2B diagrammatically depict the axle of a trailered vehicle equipped with a load coupling apparatus according to a second embodiment of this invention. FIG. 2A presents an end or longitudinal view, while FIG. 2B presents a side or lateral view illustrating the operation of the load coupling apparatus of FIG. 2A .
FIGS. 3A and 3B diagrammatically depict the axle of a trailered vehicle equipped with a load coupling apparatus according to a third embodiment of this invention. FIG. 3A presents an end or longitudinal view, while FIG. 3B presents a side or lateral view illustrating the operation of the load coupling apparatus of FIG. 3A .
FIG. 4 depicts a fifth-wheel coupling for connecting a towing vehicle to the trailered vehicles of FIGS. 1A–1B , 2 A– 2 B and 3 A– 3 B.
FIG. 5 illustrates an application of the present invention to a tractor of a tractor-trailer vehicle.
FIGS. 6A–6B diagrammatically depict the chassis and wheel of a vehicle equipped with a load coupling apparatus according to a fourth embodiment of this invention. FIG. 6A depicts the load coupling apparatus in a rest position, while FIG. 6B depicts the load coupling apparatus with the vehicle wheel displaced relative to the vehicle chassis.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is described herein primarily in the context of roadway vehicles, and particularly semi-tractor-trailers. However, it will be understood that the invention is also directly applicable to other roadway vehicles, as well as to railway vehicles, and off-road vehicles such as agricultural vehicles, bicycles, etc.
As indicated above, the present invention is fundamentally directed to a load coupling apparatus for pivotally suspending the load weight of a wheeled vehicle below the wheel axles or center-points so as to allow limited relative displacement of the wheels and the load in the direction of vehicle travel. In the case of a towed or trailered vehicle where there is no mechanism for driving the wheels, the wheel axles are displaced by a drawbar coupled to the towing vehicle. FIGS. 1A–1B , 2 A– 2 B and 3 A– 3 B depict three different possible mechanizations of a trailered vehicle load coupling apparatus, but it will be appreciated that other mechanizations are also possible. In general, FIGS. 1A–1B depict an embodiment of the load coupling apparatus in which the swinging linkage member pivots about the axle 16 , and the drawbar is coupled to the swinging linkage member itself, whereas FIGS. 2A–2B and 3 A– 3 B depict embodiments of the load coupling apparatus in which the swinging linkage member is hung from the axle 16 , and the drawbar 22 is coupled to the wheel or axle. The drawbar may be directly coupled to the towing vehicle, or through a fifth-wheel assembly as illustrated in FIG. 4 .
In each of the FIGS. 1A , 2 A and 3 A, the reference numeral 10 generally designates a wheel/axle assembly of a trailered vehicle. The tire sets 12 , 14 may each comprise one or more individual tires, and are supported on the axle 16 in the usual way. The load coupling apparatus ( 18 in FIGS. 1A–1B , 18 ′ in FIGS. 2A–2B , and 18 ″ in FIGS. 3A–3B ) is symmetrical about the longitudinal axis of the trailer 10 , and couples the trailer bed 20 to the axle 16 . One or more drawbars 22 are coupled between the towing vehicle (not shown) and the load coupling apparatus or the wheel/axle assembly to impart motion to the trailer 10 .
Referring particularly to the embodiment of FIGS. 1A–1B , each load coupling apparatus 18 includes two members: a load support member 24 and a swinging linkage member 26 . A set of bolts or pins 28 rigidly couple the upper end of load support member 24 to the trailer bed 20 , and a pin 30 rotatably couples the lower end of load support member 24 to the lower end of swinging linkage member 26 . The swinging linkage member 26 is rotatably supported on the respective end of axle 16 , and the drawbars 22 are coupled to the upper end of the swinging linkage member 26 . Finally, a cross-bar 32 interconnects the swinging linkage members 26 on the left and right sides of trailer bed 20 .
The side view of FIG. 1B illustrates the operation of the load coupling apparatus 18 when the drawbars 22 are initially pulled forward (i.e., to the right in FIG. 1B ) by the towing vehicle. The lever action of swinging linkage member 26 amplifies the force applied to pin 30 , but the force is predominantly applied to axle 16 due to the inertia of the trailer bed 20 and its load. The load coupling apparatus 18 allows movement of the axle 16 relative to the trailer bed 20 , and the forward movement of drawbar 22 rotates the swinging linkage member 26 about axle 16 (as indicated by the dashed member 26 a ). The rotation of swinging linkage member 26 produces initial forward displacement of the axle 16 and tire set 12 (as indicated by the dashed members 12 a , 16 a and 26 a ), and slightly elevates the trailer bed 20 (as indicated by the pin position 30 a and the dashed member 20 a ). The load support member 24 concentrates the weight of the trailer bed 20 and its load at the pin 30 , and the weight creates a restoring force for repositioning the pin 30 directly under the axle 16 . A forward component of this restoring force aids the force applied to drawbars 22 by the towing vehicle, and the trailer bed 20 begins to move forward as the forward force component overcomes the combined inertia of the trailer bed 20 and its load. While the initial rotation of the swinging linkage member 26 has been exaggerated in FIG. 1A for the sake of illustration, it is estimated that the forward component of the load weight will produce initial forward movement of the trailer bed 20 and its load upon forward rotation of the swinging linkage member 26 by 2–5 degrees. As the towing vehicle continues to pull the drawbars 22 forward, the trailer bed 20 and its load continue to track the axle 16 at a reduced displacement. Of course, an equivalent but opposite relative displacement of the axle and trailer bed 20 occurs when the towing vehicle pushes the drawbars 22 when operating in reverse. Although not depicted in FIGS. 1A–1B , a damper can be used to prevent or severely attenuate forward motion of the trailer bed 20 when the towing vehicle decelerates or brakes.
In the embodiment of FIGS. 2A–2B , the load coupling apparatus is designated by the reference numeral 18 ′, and includes a swinging linkage member 40 that is hung from a pin 42 positioned above the axle 16 . The pin 42 is supported on a stand-off member 44 that is either integral with the axle casting or rigidly secured thereto. Also, the drawbars 22 in this embodiment are coupled either directly to the axle 16 as shown, or to the stand-offs 44 . In other respects, the load coupling apparatus 18 ′ is similar to the load coupling apparatus 18 of FIGS. 1A–1B , and like reference numerals have been used to identify like elements.
In the illustration of FIG. 2A , the load coupling apparatus 18 ′ is repeated not only at each end of axle 16 , but also directly inboard of each tire set 12 , 14 . It will be noted that the pins 42 of each inboard load coupling apparatus 18 ′ are positioned rearward of the axle 16 to prevent interference between the axle 16 and the respective linkage members 24 and 40 in the rest position. If the pins 42 are positioned such that the inboard load support members 24 abut the axle 16 in the rest position, relative displacement of the axle 16 and trailer bed 20 will not be possible when the towing vehicle operates in reverse, and the trailer bed 20 will not be able to shift forward of the axle 16 during forward motion of the trailer when the towing vehicle decelerates or brakes. If the inboard load coupling apparatuses 18 ′ are omitted, relative displacement of the axle 16 and trailer bed 20 will occur during both forward and reverse operation of the towing vehicle, and a damper may be provided to prevent or severely attenuate over-center shifting of the trailer bed 20 when the towing vehicle decelerates or brakes.
The side view of FIG. 2B illustrates the operation of the load coupling apparatus 18 ′ when the drawbars 22 are initially pulled forward (i.e., to the right in FIG. 2B ) by the towing vehicle. The force applied to drawbars 22 produces forward motion of axle 16 and rotation of swinging linkage member 26 about pin 30 (as indicated by the dashed members 12 a , 16 a and 40 a ), slightly elevating the trailer bed 20 (as indicated by the pin position 30 a and the dashed element 20 a ). The load support member 24 concentrates the weight of the trailer bed 20 and its load at the pins 30 , and the weight creates a restoring force for repositioning the pins 30 directly under the respective pins 42 . A forward component of this restoring force aids the force applied to drawbars 22 by the towing vehicle, and the trailer bed 20 begins to move forward as the forward force component overcomes the combined inertia of the trailer bed 20 and its load. As the towing vehicle continues to pull the drawbars 20 forward, the trailer bed 20 and its load continue to track the axle 16 at a reduced displacement.
In the embodiment of FIGS. 3A–3B , the load coupling apparatus is designated by the reference numeral 18 ″, and includes a swinging linkage member 46 that is hung from the axle 16 or wheel 12 . The drawbars 22 are coupled to the hub 48 of a small sprocket 50 that pivots about a pin joint 52 on trailer bed 20 , and a chain 54 couples the sprocket 50 to a large sprocket 56 rigidly secured to the axle 16 . Alternatively, the sprockets 50 , 56 and chain 54 may be replaced with similarly sized pulleys and a belt. The small sprocket 50 is positioned near the upper periphery of the large sprocket 56 so that the force exerted on drawbar 22 by the towing vehicle is essentially applied to the top of the sprocket 56 , providing increased mechanical advantage compared to the embodiment of FIGS. 2A–2B , for example. In other respects, the load coupling apparatus 18 ″ is similar to the load coupling apparatus 18 of FIGS. 1A–1B , and like reference numerals have been used to identify like elements. FIG. 3B depicts the load coupling apparatus 18 ″ following an initial forward movement of the drawbar 22 and axle 16 .
While the drawbars 22 for the above-described embodiments of the load coupling apparatus may be attached directly to the towing vehicle, FIG. 4 illustrates a preferred implementation in which the drawbars 22 are connected to the towing vehicle via a modified fifth-wheel coupling. Referring to FIG. 4 , the reference numeral 58 designates a portion of a fifth-wheel coupling in which a hitch pin 60 is received in a slot 62 a of a skid plate 62 mounted on the towing-vehicle. The drawbar 22 is coupled to the skid plate 62 by the pin 64 near the open end of the slot 62 a , creating a lost-motion coupling between the hitch pin 60 and the skid plate 62 . The hitch pin 60 is initially in a forward position as shown in FIG. 4 , and forward movement of the towing vehicle produces a pulling force on the drawbar 22 without applying any forward force to the hitch pin 60 . The hitch pin 60 will move back and forth in the slot 62 a with the relative displacement of the load coupling apparatus 18 , 18 ′, 18 ″, and its steady-state position within the slot 62 a will be a function of road grade, air resistance, and so forth. A damper mechanism 66 such as a shock absorber or the like couples the hitch pin 60 to the chassis of the towing vehicle to prevent or severely attenuate forward shifting of the trailer bed and its load when the towing vehicle decelerates or brakes (in embodiments where such motion is possible).
FIG. 5 depicts an application of the load coupling apparatus of the present invention to a towing vehicle 68 , such as the tractor of a tractor-trailer vehicle. In such vehicles, an engine or motor 70 provides motive power by rotating one or more drive wheels of the vehicle, and there is no need for a drawbar such as used for trailered vehicles. In the embodiment of FIG. 5 , the towing vehicle 68 has a front wheel set 71 , and tandem rear axles 72 , 74 , with rear wheel sets 76 , 78 . The engine 70 drives the rear axles 72 , 74 through a conventional drivetrain including a jointed drive shaft 80 and a differential gearset (not shown). The vehicle chassis 82 is coupled to the front wheel set 71 in a conventional manner, and to each of the rear axles 72 , 74 using load coupling apparatuses 84 , 86 according to this invention. For example, the load coupling apparatuses 84 , 86 may be constructed as shown in FIGS. 2A–2B or 3 A– 3 B, but without the drawbars 22 . A fifth wheel assembly 88 such as depicted in FIG. 4 is attached to the chassis 82 for coupling to a trailer hitch pin. Finally, the engine 70 is pivotably suspended from the chassis 82 via the swing arms 89 a , 89 b , which of course are repeated on the opposite side of engine 70 . In operation, the application of motive power from the engine 70 to the rear axles 72 , 74 produces a forward movement of the axles 72 , 74 and engine 70 relative to the chassis 82 , after which the chassis 82 and load follow once the swinging linkage members of the load apparatuses 84 , 86 develop enough forward force to overcome the inertia of the suspended weight.
Finally, FIGS. 6A–6B depict an embodiment of the load coupling apparatus of the present invention that is well suited to both trailered vehicles (including manually towed vehicles) and manually powered vehicles such as wheelchairs and the like. Ordinarily, of course, the weight of the vehicle chassis 90 and load is mounted on the wheel axles. In the case of a wheelchair, the user grasps the top of the wheel 92 and pushes it forward or rearward to initiate movement. Although the wheel afford a mechanical advantage that multiplies the user's force, the applied force has to be sufficient to initiate movement of the entire weight of the vehicle and its occupant (load), just as in the case of any conventional vehicle.
Referring particularly to FIG. 6A , the wheel 92 is essentially a cylinder having an inner periphery 92 a on which ride three idler wheels: a follower wheel 94 and a pair of offset wheels 96 and 98 . Alternatively, the idler wheels 94 , 96 , 98 may be constructed as pulleys, and the inner wheel periphery 92 a notched to constrain lateral movement of the pulleys. The load coupling apparatus comprises load support members 100 , 102 , a swinging linkage member 104 , and an offset wheel arm 106 which may be integral with swinging linkage member 104 . The load support members 100 , 102 are rigidly fastened to the chassis 90 , and to a support plate 108 welded to the axle hub of follower wheel 94 . The swinging linkage member 104 is pivotably coupled to the plate 108 on pin joint 110 , and the offset wheel arm 106 supports the offset wheels 96 , 98 on the pins 114 , 116 at its opposing extremities, allowing the swinging linkage member 104 and offset arm 106 pivot as the wheel 92 is displaced with respect to the chassis 90 as shown in FIG. 6B . If the vehicle is a trailered vehicle, the swinging linkage member 104 can be extended upward as illustrated in phantom and designated by the reference numeral 112 ; in this case, a drawbar (not shown) pulls the top of swinging linkage member 104 forward, producing the relative displacement illustrated in FIG. 6B . Alternatively, a belt or chain drive arrangement of the type depicted in FIGS. 3A–3B could be utilized. If the vehicle is not a trailered vehicle, the upper extension of swinging linkage member 104 is omitted, and the swinging linkage member 104 pivots as shown in FIG. 6B when the wheel 92 is rotated forward. Rotation of the wheel 92 may be achieved either by hand, as in the case of a typical wheelchair, or by machine, in which case an electric (or hydraulic) motor is directly or indirectly coupled to the wheel 92 . In either case, the chassis 90 raises slightly as the follower wheel 94 tracks the inner periphery 92 a of wheel 92 . The combined weight of the chassis 90 and load are concentrated at the pin joint 110 , producing a force in the desired direction of travel, and when that force overcomes the inertia of the chassis 90 and load, the chassis 90 and load support members 100 , 102 will move forward in a swinging motion. As with the other vehicles depicted herein, the chassis 90 and load support members 100 , 102 will tend to lag the center of the wheel 92 so long as the wheel 92 is being pulled or pushed forward, and the return to the rest position depicted in FIG. 6A . Movement in the opposite direction is initiated in much the same way by pulling the swinging linkage member extension 112 , or pushing the wheel 92 , to the right as viewed in FIGS. 6A–6B .
It will be appreciated that the load coupling apparatus of this invention is also applicable to tracked vehicles such as tanks where a rubber or steel track encircles front and rear wheels of a vehicle. In such an application, the load coupling apparatus of FIGS. 6A–6B may be applied to both front and rear wheels of the vehicle. In a particularly advantageous configuration, only one of the front and rear wheels is motor-driven, and the swinging linkage members of the front and rear wheels are coupled by a mechanical or hydraulic link (a drawbar, for example) so that the motor effectively drives both front and rear wheels.
In summary, the present invention provides an improved load coupling apparatus that significantly reduces the effort required to initiate and maintain movement of a wheeled vehicle. As applied to a manually propelled vehicle such as a wheelchair, the user effort level is significantly reduced, making the wheelchair so equipped particularly beneficial to persons with limited upper body strength. As applied to trailered and towing vehicles, the peak motive power requirements are significantly reduced, contributing to substantial improvements in fuel economy and emissions, and lower initial powertrain expense. While the invention has been described in reference to the illustrated embodiments, it should be understood that various modifications in addition to those mentioned above will occur to persons skilled in the art. Accordingly, it will be understood that systems incorporating these and other modifications may fall within the scope of this invention, which is defined by the appended claims. | A load coupling apparatus for a wheeled vehicle includes load linkage members that pivotally suspend the vehicle and load weight below the axles of the vehicle, allowing limited relative displacement of the axles and the load in the direction of vehicle travel. The load is displaced by moving the axles in the desired direction of travel, whereafter the suspended load follows the axles in a swinging motion as the effects of gravity overcome the load inertia. The effort required to initiate movement of the load is significantly reduced due to the relative displacement of the axles and the load, and the mechanical advantage afforded by the load linkage members. Once in motion, the load continues to track the axles in the direction of travel, providing continued reduction in motive effort even when the load reaches a constant forward speed. | 1 |
CROSS REFERENCES TO RELATED APPLICATIONS
This application is related to an application in the names of James E. Smith and Carl T. Becht, Ser. No. 810,903 filed June 28, 1977, entitled "Electro-Mechanical Impact Device" , now U.S. Pat. No. 4,121,745, and an application in the name of James E. Smith and Carl T. Becht, Ser. No. 880,448 now U.S. Pat. No. 4,189,080, filed Feb. 23, 1978, entitled "Impact Device".
BRIEF SUMMARY OF THE INVENTION
U.S. Pat. No. 4,042,036 in the names of James E. Smith and James D. Cunningham discloses an electric impact tool wherein a ram or impact member is disposed between a pair of counter-rotating flywheels driven by electric motors. Means are provided to swing one of the flywheels on an arc toward the other flywheel which has a fixed axis, so as to pinch the impact member between the flywheels to propel the impact member in a working stroke.
In U.S. Pat. No. 4,121,745, the counter-rotating flywheels are driven by a single electric motor, and the movable flywheel is moved by cam action, produced by pressing the nose of the tool against a work piece, to a position in which it is spaced from the fixed flywheel by a distance less than the thickness of the ram or impact member. The movable flywheel is spring-biased in this position, and will move against the opposing spring force when the ram enters between the flywheels. The ram is introduced between the flywheels by actuation of the trigger of the tool.
In Ser. No. 880,448 there is one motor driven flywheel on a fixed axis, and a back-up support means which is movable to a position in which it is spaced from the flywheel a distance less than the thickness of the ram by substantially the same means as in U.S. Pat. No. 4,121,745. The ram is brought into engagement between the flywheel and support means by actuation of the trigger of the tool.
In said pending applications, the tip of the ram is beveled to facilitate entry of the ram between the flywheels, or between the flywheel and support means, but thereafter the ram is of uniform thickness.
According to the present invention, the ram or impact member is tapered, and as a result the coefficient of friction between the ram and the flywheel can be reduced from what is required with a constant thickness ram without creating a slipped condition. Engagement of the ram and flywheel can be facilitated by an increase of the normal force exerted by the spring and by inertia, and the taper can provide for increased force later in a drive stroke while at the same time maintaining engagement normal forces at a minimum, thereby minimizing energy losses during engagement. The configuration of the ram may be a linear taper, a stepped taper, or any of a number of curved configurations, and may be symmetrical or asymmetrical about its longitudinal axis, whereby it is possible to tailor the driving characteristics to the exigencies of any particular situation.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is a front cross sectional view of a tool according to U.S. Pat. No. 4,042,036.
FIG. 2 is a similar view of a tool according to either of said copending applications.
FIGS. 3 to 9 inclusive are fragmentary edge views of a ram showing several possible configurations.
DETAILED DESCRIPTION
U.S. Pat. No. 4,042,036 gives a very complete analysis of the parameters involved in order to make it possible to drive a 16 penny nail into medium hard wood. In that analysis, a peak force of 1,000 pounds (450 kg) is found to be required to accomplish the drive, and approximately 125 foot pounds (17.28 kg-m) of energy is required. It is disclosed that a 3 inch (7.6 cm) solid brass flywheel 1 inch thick, rotating at 7000 rpm. will satisfy these requirements.
The patent further teaches that the ram engaging force between the flywheels against the ram is about three times the work force needed in the ram. This ram engaging force is achieved by mounting the movable flywheel on an arm pivoted above a line normal to the ram and passing through the centers of the flywheels when in operative position. The movable flywheel is swung into operative position, and as it engages the ram and forces it against the fixed axis flywheel, its direction of rotation is such as to tend to roll it further in the engagement direction and thereby to increase the pressure it exerts on the ram.
This arrangement is diagrammatically shown in FIG. 1, wherein the flywheel rotating on a fixed axis is indicated at 10 and the movable flywheel is indicated at 11. The flywheel 11 is mounted on an arm 12 pivoted at 13. The flywheels 10 and 11 rotate in the direction indicated by the arrows, and drive the ram 14 which is pinched between them and which drives the nail 15. The patent teaches that, in order to prevent slippage between the flywheel and ram, the coefficient of friction between the flywheel 11 and ram 14 must be equal to, or greater than, tan θ, where θ is the acute angle at the intersection of a plane defined by the spin axis of the movable flywheel and its axis of pivotal movement, and a second plane perpendicular to the direction of movement of the ram.
A dynamic analysis of this system reveals that compensation for rapid changes in the required drive force require large angular accelerations of the pivoting flywheel assembly about the suspension axis. When it is borne in mind that drive strokes on the order of one millisecond and relatively large flywheel inertias are involved, it is found that the force required for angular acceleration of the flywheel assembly to provide the necessary friction force may easily be an order of magnitude greater than that required to drive a large nail. In other words the inertia of the flywheel about the suspension axis inhibits clutch regenerative action in the arrangement of FIG. 1.
The devices of the copending applications, Ser. Nos. 810,903 and 880,448, are illustrated in FIG. 2. As can be seen in that FIG. 2, the movable flywheel 11a is mounted in a clevis 16 which is moved toward and away from the flywheel 10a by the action of a cam 17 operating between the clevis 16 and a spring plate 18. Spring means 19 normally bias the flywheel 11a, in its clevis 16, away from the flyweel 10a. A comparison of the devices of FIGS. 1 and 2 illustrates the differences between the copending applications and U.S. Pat. No. 4,042,036. In the device of FIG. 1, representative of U.S. Pat. No. 4,042,036, the ram 14, in its starting position, is between the flywheels, which pinch it between them to initiate the working stroke. In the device of FIG. 2, representative of said copending applications, the ram 14a, is initially above the bite of the flywheels. The cam 17 moves the flywheel 11a toward the flywheel 10a to a position in which the space between the flywheels is less than the thickness of the ram. The ram is then introduced between the rotating and closely spaced flywheels, and spring plate 18 yields to permit ram entry between the flywheels. The inertia of the flywheels opposes their separation upon introduction of the ram, and therefore assists in the efficient engagement of the flywheels and ram.
It should be noted that the rams of U.S. Pat. No. 4,042,036 and the said copending applications are of constant thickness, although the copending applications disclose a beveled tip to facilitate the entry of the ram between the flywheels. The ram, beyond the tip, is of constant thickness.
According to the present invention, the ram is tapered as shown in FIG. 3. It should be observed that FIGS. 3 to 9 inclusive, being edge-on-views of a ram, are greatly enlarged, and their configurations are exaggerated. With the use of such a tapered ram in the system of U.S. Pat. No. 4,042,036, the flywheel inertia about its suspension axis 13 (FIG. 1) is helpful and augments the clutch operation. In this situation the flywheel must accelerate angularly in the opposite direction during the millisecond drive time. Now large normal forces are exerted on the ram by virtue of the angular acceleration of the flywheel suspension system, so that the coefficient of friction between the ram and the flywheel can be even less than tan θ without creating a slip situation. The normal force of the flywheel against the ram is increased during the drive. This increased force aids in the initial engagement, and can provide increased force at a later point in the drive, while keeping the engagement normal forces at a minimumm, so as to minimize energy losses during engagement.
Similarly in the devices of said copending applications (FIG. 2), the inertial force and the spring force, both of which work in favor of maintaining driving friction, are enhanced by the use of a tapered ram, as shown in FIG. 3.
As seen in FIGS. 4 through 6 and FIGS. 7 through 9, the ram taper may be varied. In FIG. 4 the taper is stepped. In FIG. 5 it is increased rather rapidly on a curve; and in FIG. 6 a more complex taper is shown, partly positive and partly negative. FIGS. 4, 5 and 6 illustrate asymmetrical ram tapers. The ram taper may be, of course, symmetrical about the longitudinal axis of the ram, as illustrated in FIGS. 7, 8 and 9.
By varying the taper as suggested in FIGS. 4 through 9, it is possible to tailor the normal force on the ram during ram travel for different purposes, or in other words, to tailor the normal force as a function of ram position.
It will be understood that numerous variations may be made without departing from the spirit of the invention. Therefore no limitation not expressly set forth in the claims is intended, and none should be implied. | An impact member for driven flywheel impact devices, such as nailers and staplers, is disclosed which may be configured to tailor the normal force as a function of ram position. A basic configuration is a constant taper, which, as soon as the impact member is actuated by a flywheel, assists in maintaining driving friction on the impact member. The taper may be linear, stepped or curved, and symmetric or asymmetric about the longitudinal axis of the ram, whereby to tailor the impact member speed for different purposes. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 09/887,772, filed Jun. 21, 2001, now pending, which application is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to floor structures, and more specifically to a floor assembly having removable access panels supported on a grid that is supported on a plurality of primary and secondary structural supports.
2. Description of the Related Art
The increase in the use of computers, communication devices, and other electronic hardware has placed new demands on building designers. Users desire a large number of outlets for access to electrical power and communication signals, and they need the ability to change the location of such outlets on a regular, sometimes frequent basis. Power and data outlets have been located in, or under, a floor, typically in removable floor sections elevated above the original floor by supports. Two typical types of elevated floors are the pedestal floor and the low-profile floor.
The pedestal access floor has pedestals that consist of metal rods with a base plate at one end and a supporting plate on the other that supports removable horizontal panels, thus forming a raised floor structure. The metal rods are height adjustable and rest on a conventional solid floor deck. The solid floor deck may be made of wood, concrete, or a combination of metal deck and a deck may be made of wood, concrete, or a combination of metal deck and a concrete topping slab. The rods are arranged in a grid, typically square. The rods and plates support removable floor sections. The height of the rods is typically about 12 to 18 inches and can be adjusted to a desired height prior to installing the floor sections. Electrical power and data cables are laid between the solid floor deck and the underside of the floor sections. The cables penetrate the floor sections at a desired location to suit the user's needs. The penetrations may consist only of openings for cables, or may be junction boxes, similar to common electrical wall outlets. The penetrations may accommodate power wires, or signal cables such as cable television, speaker wire, computer networks, etc. In some designs, the space between the floor deck and the elevated floor sections is configured to enable the distribution of conditioned air through grilles and/or registers located in selected floor sections. A flooring system of the type described above is disclosed in U.S. Pat. No. 3,396,501, issued to D. L. Tate on Aug. 13, 1968.
There is a labor premium involved in having to locate and install the foregoing pedestal system. The pedestals must be braced to meet seismic code, further increasing labor and cost. Moreover, the pedestals increase ceiling height requirements, and ultimately the height of the building, which increases the area of the exterior envelope, thereby increasing not only construction costs but also operating costs due to heat loss. If the pedestal access floor is only used in parts of a building, ramps or structural accommodations must be made for the changes in floor elevation. As users re-route electrical cables below the access floor, the pedestals may present an impediment in pulling cables to a new location. The access floor also represents another step in the construction schedule. The acoustical properties of this system are poor. The floor sections are usually relatively thin and rigid and transmit sound both horizontally and vertically.
A second type of elevated floor is a low-profile design, which may be roughly 2½ inches to 4 inches high. This design does not use pedestals to raise and support the floor sections, but rather relies on “feet” at the corners of the sections to create the space above the solid floor deck and below the underside of the panel. The panels, with low “feet,” rest directly on the floor deck. This low-profile design is less costly than the pedestal floor, but still impacts the cost of a traditionally designed floor in a building because it requires the use of a solid floor deck. The problem of elevation changes between the existing conventional floor and accessible floor also remains.
There are also disadvantages to the low-profile floor compared to the pedestal floor. The space below the low-profile sections is not deep enough to be used to supply air. The resulting floor is not as stable, in either the horizontal or vertical dimension, as the pedestal access floor described above. Since the sections are not fastened to the floor deck, they can move when cable is being pulled and re-routed. It also increases the floor-to-floor height of the building, and thus the construction and operating costs. In general, the smaller distance between the solid floor deck and the surface of the floor sections decreases the flexibility of the low-profile floor. Both types require an underlying solid floor deck for support and to provide structural stability to the exterior building.
In addition, the acoustical characteristics of both common types of elevated floors are typically very poor. They tend to transmit noise to a degree that makes them impractical for use in many environments.
Another type of accessible floor is disclosed in U.S. Pat. No. 3,583,121, issued to D. L. Tate on Jun. 8, 1971. This system includes two layers of bar joists laid one on top of the other at right angles thereto. Panels laid over the upper layer may be configured to be removable, to provide access to space underneath. One disadvantage of this system is the height of the two layers of joists and the added height this imparts to a building. Additionally, the joists must be laid at least as closely together as the width of the panels. The resulting weight and depth of the system is too great to be practical except where particularly heavy loads are imposed on the floor. Also, the joists have to be welded at each intersection greatly increasing field labor costs.
BRIEF SUMMARY OF THE INVENTION
In accordance with one embodiment of the invention, a floor assembly for a building is provided, the floor assembly having a plurality of primary structural building members, a plurality of spaced-apart secondary structural building members spanning the primary building members, a support grid on the top surfaces of the secondary building members, and a plurality of panels mounted on the support grid to form the floor, with each of the panels individually removable from the support grid to provide access to the space beneath.
According to an alternative embodiment of the invention, a floor assembly is provided that includes a plurality of longitudinal structural supports, a grid assembly, an attachment system attaching the grid assembly to the upper surface of each of the longitudinal structural supports and configured to enable adjustment in the position of the grid assembly relative to the longitudinal structural supports, and a plurality of panels, the bottom portion of the panels configured to be received into openings in the grid, and the top portion configured to bear against a top surface of the grid assembly.
According to another embodiment of the invention, a floor system is provided, that includes a prefabricated floor section. The floor section comprises a plurality of support rails positioned a selected distance apart, each having a pair of spaced apart angle members with spacers positioned between the angle members. The support rails are configured to extend between two secondary structural members of a building. The floor section also includes a plurality of cross rails, each spanning between adjacent pairs of support rails, the support rails and cross rails together defining, between adjacent pairs of support rails and adjacent pairs of cross rails, a plurality of apertures, with each aperture configured to receive a removable floor panel.
In accordance with another embodiment of the invention, a building is provided that includes a plurality of primary structural building members, a plurality of spaced-apart secondary structural building members spanning the primary building members, a support grid affixed to the top surfaces of the secondary building members and configured to receive panels, an attachment system attaching the support grid to the top surface of each of the secondary structural building members and configured to enable adjustment in the position of the support grid relative to the secondary structural building members, and a plurality of panels received in the support grid to form a floor, each of the panels individually detachable from the support grid to provide access to the space between the secondary structural building members.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
FIG. 1 shows an isometric view of a section of the floor system formed in accordance with one embodiment of the present invention;
FIG. 2 shows a detail of a structural support grid element of a floor system formed in accordance with another embodiment of the present invention;
FIG. 3 is a cross-sectional view taken along line III-III of a portion of the floor system of FIG. 1 ;
FIG. 4 is a cross-sectional illustration of an alternative embodiment of the floor system of FIG. 3 taken along line IV-IV;
FIG. 5 is a plan view of a floor system according to another embodiment of the invention;
FIG. 6 is a plan view of a floor system according to an alternative embodiment of the invention;
FIG. 7 is an isometric view of a further embodiment of a floor system of the present invention;
FIG. 8 is an isometric view of a floor system illustrating an alternative embodiment of the present invention;
FIG. 9 is a partially exploded view of a flooring system according to another embodiment of the invention;
FIG. 10 is a more detailed view of the system of the embodiment of FIG. 9 ;
FIG. 11 shows a detailed view of a feature of the embodiment of FIG. 9 ;
FIG. 12 is a cross sectional view of the portion of FIG. 10 indicated at lines XII-XII;
FIG. 13 is a partial cut-away plan view of the system of FIG. 9 ;
FIG. 14 is a cross sectional view of the portion of FIG. 9 indicated at lines XIV-XIV; and
FIG. 15 is a cross sectional view of the portion of FIG. 9 indicated at lines XV-XV.
DETAILED DESCRIPTION OF THE INVENTION
The structurally integrated accessible floor system, hereinafter referred to as the floor system, is designated generally as 100 , and is shown isometrically in FIG. 1 .
Primary framing members 102 are provided, which can be formed as integral parts of metal frame type buildings. Secondary framing members, such as joists 104 are connected to the primary framing members 102 . According to one embodiment of the invention, a structural support grid 106 is then formed bearing on the secondary framing members 104 . The grid 106 is configured to receive removable floor panels 108 in the openings 110 formed by the grid 106 .
The grid 106 is configured to span across the secondary framing members 104 such that a plurality of floor panels 108 are supported by the grid between each secondary framing member 104 , without the need for support by a secondary framing member for each floor panel 108 . For example, the grid 106 is shown in FIG. 1 spanning across a distance D between two secondary framing members 104 while supporting the width of three panels 108 in that same distance. This is in contrast to conventional removable flooring systems, in which each removable panel is generally supported by a grid having a leg, post, or pedestal at each corner of each panel.
The removable floor panels 108 are of a uniform size to allow interchangeability, and they may be provided with terminals or hookups 112 for electrical power and communication access, and with vents or registers 114 for ventilation.
For the sake of convenience and clarity, one type of power terminal 112 is shown in FIG. 1 . However, it will be obvious to those skilled in the art that a wide variety of terminals may be used, including standard 110 volt sockets, coaxial cable terminals, fiber optical connections, heavy duty power terminals, T2 connectors, etc. A user may further choose to provide an opening in the panel to enable the passage of cable without the use of a terminal. These and other options are considered to be within the scope of the invention.
By the same token, a wide variety of means to transmit air and gas may be used in place of the vent 114 , including compressed air hookups, vacuum lines, fans, directionally adjustable vents, filters, emergency gas evacuation systems, compressed oxygen, CO 2 , propane, nitrogen, etc.
FIG. 1 also shows optional panels 116 attached to metal channels 118 , which are in turn affixed to the underside of the secondary framing members. These panels 116 are ideally constructed of material that resists fire, thus forming a fire block. The panels 116 isolate one story of a building from the next, establishing fire protection, which may be required by many building codes. The panels 116 attached to the underside of the secondary framing members enclose the space between the secondary framing members. This enclosed space may be employed as a plenum for HVAC. This can result in a financial savings, because ductwork is reduced or eliminated. Partitions may be used within this space to permit discreet sections of the floor system to pressurize for use as a plenum.
Referring next to FIG. 2 , shown therein is a section of one embodiment of the structural support grid 106 . According to this embodiment, the structural support grid comprises L-shaped rail members 202 affixed in back-to-back relationship to T-shaped joint nodes 200 to form supports for the removable floor panels. The nodes and rail members are standardized to permit interchangeability.
It is to be understood that the rail members may have many different cross-sectional shapes and node configurations. For example, some alternative cross-sectional shapes include channel, “T”, and square.
FIG. 3 shows the floor system 100 in cross-section taken along lines III-III in FIG. 1 . The removable floor panel 108 has a plurality of layers, including a top layer 300 , which is configured according to the requirements of the particular application and may have a carpeted surface or a tile surface. Alternatively, the top surface 326 may be formed using chemically resistive materials for use in a lab or other caustic environments. The top layer 300 and a bottom layer 306 are designed to provide structural stiffness to the panel 108 and are configured according to the structural and weight bearing requirements of the particular application. Fire retardant layers 304 may also be structural and are composed of fire resistant materials such as gypsum, or other appropriate material, and serve to inhibit the passage of fire from one side of the panel 108 to the other. An insulation layer 302 provides thermal and acoustic insulation, and may be slightly oversized to provide a friction fit in the grid.
It will be understood that the composition of the removable floor panels will vary according to the requirements of a particular application and will in part be dictated by the anticipated environment, the required load carrying capacity, the desired appearance, the anticipated degree of noise control, local building and fire codes, and other factors.
Although the removable floor panels 108 bear against the structural support grid 106 , panel fasteners 310 may be used to positively attach the panels 108 to the structural support grid 106 . In the embodiment shown in FIG. 3 , the panel fasteners 310 comprise threaded fasteners that pass from a lower surface of the structural support grid 106 into an opening in a lower surface of the removable panel 108 via an opening 311 in the rail member 202 of the structural support grid 106 . The opening 311 is oversized in relation to the threaded fastener 310 to enable adjustment in the position of the removable panel 108 relative to the structural support grid 106 . The threads of the threaded fastener 310 engage the removable panel and a hexagonal head of the fastener 310 bears against the lower surface 324 of the support grid 106 , drawing the removable panel tight against the structural support grid 106 . Thus, in this embodiment access to the panel fasteners 310 is from beneath the structural support grid 106 .
A leveling unit 308 is provided to control a vertical distance 320 between the structural support grid 106 and the secondary framing members 104 . FIG. 3 shows one of a plurality of similar units that comprise the leveling system, which functions as described below.
As shown in FIG. 3 , the leveling unit 308 includes a threaded rod 312 attached to a support plate 314 that bears against an upper surface 322 of the secondary framing member 104 . The threaded rod 312 passes through a lift plate 316 via an opening in the lift plate 316 , with the lift plate 316 bearing upward against the lower surface 324 of the structural support grid 106 . The rod 312 is slideably received in an opening 307 formed in the grid 106 . A pair of jam nuts 318 on the threaded rod supports the lift plate 316 . The position of the jam nuts 318 on the threaded rod determines the distance 320 between the upper surface 322 of the secondary framing member 104 and the lower surface 324 of the structural support grid 106 .
By adjusting each of the plurality of units of the leveling system, the bearing surface 326 of the floor system 100 can be leveled, even if the upper surfaces 322 of the secondary framing members are not level.
In another embodiment of the invention, leveling devices that are functionally similar to the leveling unit 308 described above may be employed between an upper surface 120 (shown in FIG. 1 ) of the primary framing members 102 and the part 105 of the secondary framing members 104 that bears against the primary framing members. By adjusting the vertical distance between the primary and secondary framing members, the level of the structural support grid 106 can be controlled.
Other methods of controlling the vertical distance (not shown) between the primary and secondary framing members 102 , 104 , or between the structural support grid 106 and the secondary framing members 104 will be obvious to those skilled in the art. These methods include the use of wedges, shims, threaded devices that are accessed from above the floor system, automatic or remotely adjustable devices, etc., all of which are deemed to be within the scope of the invention.
FIG. 4 is a cross-sectional view of a floor system 100 , taken along line IV-IV, and shows an alternative embodiment of the removable panel 108 . In this embodiment, a flexible gasket 400 is affixed to the top edge 412 of each panel 108 , 109 . The gaskets 400 of adjoining panels 108 , 109 press against each other, providing a seal between the removable panels 108 , 109 . The seal may be employed to prevent spills from leaking through the floor system. In applications where spills of caustic or dangerous fluids might be anticipated, the composition of the gasket 400 is chosen to be resistant to the particular classes of substances in use. Multiple or interlocking gaskets may also be employed to provide a more secure seal. Alternatively, a single gasket may be wedged between the adjoining panels 108 , 109 after they are installed on the structural support grid 106 . The gasket 400 may also be used in applications where it is desirable to control the movement of air or other gasses from one side of the floor system to the other.
FIG. 4 also shows an alternative embodiment of the panel fasteners. Here, the panel fastener 410 is accessed with a tool (not shown) that is inserted from above the surface of the floor system into the center of the joint node 200 . The panel fastener 410 is rotated approximately 45°. Fastener blades 408 rotate from positions in slots (not shown) in the joint node 200 into slots in the corners of the removable panels 406 , locking them in place.
Other locking devices and systems will be evident to those skilled in the art and are considered to be within the scope of the invention. Such devices include those employing cam-type fasteners, devices that are accessible from the surface of the removable floor panels, devices that latch automatically when the removable floor panels are emplaced, etc.
Depending upon the height and local requirements, some buildings include devices or methods of construction that provide earthquake resistance. In conventional construction methods a solid floor deck functions as a diaphragm, which is resistant to dimensional stresses.
According to one embodiment of the invention, and as illustrated in FIG. 5 , the structural support grid 106 is attached orthogonally, relative to the primary 102 and secondary 104 framing members. Diagonal stays 501 are employed to brace and provide the requisite stability to the structure. The stays 500 are attached directly to the primary columns 502 of a building and pass underneath the floor structure 500 .
FIG. 6 shows floor structure 600 according to an alternative embodiment of the invention, in which the structural support grid 106 is oriented diagonally, relative to the primary 102 and secondary 104 framing members. In this embodiment, the structural support grid 106 itself forms the diagonal bracing that reinforces the building structure.
In a further embodiment of the invention, and as shown in FIG. 7 , repositionable walls 702 may be employed as part of the structurally integrated accessible floor system 700 . These repositionable walls may consist of floor to ceiling room dividers, which may be assembled on site, as shown in FIG. 7 , or prefabricated and installed as individual units, or alternatively they may be prefabricated cubicle dividers of the type common in office environments. The repositionable walls 702 are affixed directly to the structural support grid 104 . Partial floor panels 108 a may be cut to the necessary size at the site, using conventional methods, or may be manufactured in common dimensions. By affixing the walls 702 to the grid 106 and employing partial floor panels, acoustical isolation is enhanced and the structural stability of the walls 702 is improved.
Electrical components in the walls 702 , such as light switches, thermostats, power connections etc, may be wired directly through the bottom of the walls via harnesses (not shown) that can be connected to cables and connectors underneath the floor panels 108 . This is a significant advantage, especially in the case of cubicle dividers, over the methods currently in use, because conventional cubicle dividers must bring power into open areas and may involve complex interconnections between the dividers, and power drops from ceilings. Other methods include the use of wireless technology for switches and controls. Such technology has the advantage that it doesn't require any wiring connections in the walls.
FIG. 8 illustrates an alternative embodiment 800 of the invention in which structural support rails 802 are employed. The rails 802 span the secondary framing members 104 and support the removable floor panels 108 on two sides. The floor panels 108 of this embodiment are configured to span the structural support rails 802 .
Another embodiment of the invention is described with reference to FIGS. 9-15 . A floor system 900 is shown in FIG. 9 as part of a building structure. The system 900 includes a prefabricated floor section 902 having a first plurality of support rails 904 . Each of the support rails 904 includes a pair of spaced-apart angle members running the full length of the section 902 . Cross-support rails 906 are positioned at regular intervals between the support rails 904 , each adjacent pair of support rails 904 and cross-support rails 906 forming an opening configured to receive a removable floor panel 908 therein.
The prefabricated floor section 902 is configured to span secondary framing members 909 of the structure. Connectors 910 are affixed to an upper surface of the secondary framing members 909 in a regularly spaced relationship, corresponding to the spacing of the support rails 904 of the prefabricated section 902 . The connectors 910 may be affixed to the upper surface of the secondary framing member 909 by any appropriate method, including welding, bolting, etc. FIG. 10 shows each connector 910 as comprising a pair of angle sections in a spaced-apart relationship. It will be understood that the connector 910 may be formed from a single T-shaped member or some other structure that provides the necessary spacing and support for the support rail 904 . The spaced-apart angle members 905 of each support rail 904 engage the connector 910 to provide positive contact between the prefabricated section 902 and the secondary framing member 909 . The support rails 904 may be affixed to the connectors 910 by a known method such as welding or bolting. Alternatively, some of the support rails 904 of the prefabricated section 902 may be affixed to their respective fasteners 910 , while others of the support rails 904 may be allowed to rest directly on the connector 910 without being positively affixed thereto. The connectors 910 may be preaffixed to the secondary framing member 909 prior to erection of the structure. For example, the secondary support member 909 may have the connectors 910 affixed thereto at a fabricating plant prior to shipment to a construction site.
Spacers 922 are positioned and affixed between the spaced apart angle members 905 of each of the support rails 904 . The spacers 922 maintain the spaced apart relationship of the angle members 905 in the embodiment shown, the spacer is illustrated as a section of square rod positioned between the angle members 905 . FIGS. 10-12 show the spacers 922 having threaded holes passing therethrough, and positioned in locations corresponding to the positions of the crossrails 906 .
The prefabricated section 902 includes subfloor rails 912 affixed to the underside of the prefabricated section 902 at right angles to the support rails 904 . In the embodiment shown in FIGS. 9-15 , the subfloor rails 912 comprise spaced-apart angle members 917 similar to those of the support rails 904 , with square spacers 915 affixed between the angle members 917 . The subfloor rails 912 run the entire width of the prefabricated section 902 , and are positioned such, that the subfloor rails 912 of adjoining prefabricated sections 902 meet in an end-to-end configuration. Splice plates 914 affixed between subfloor rails 912 of adjoining sections 902 join the subfloor rails of adjoining sections 902 together. By aligning and joining subfloor rails 912 of adjacent sections 902 together, correct positioning and spacing of adjacent prefabricated sections 902 is assured. Secondary crossrails 916 are positioned in a spaced apart relationship between adjacent sections 902 in positions corresponding to the crossrails 906 of the prefabricated floor sections 902 to provide support for removable floor panels 908 to be placed between adjacent prefabricated panels 902 .
Gaskets 924 of resilient or semi-resilient material are positioned between the floor panels 908 . The gaskets 924 may be configured to improve the sound dampening characteristics of the floor system 900 . The gaskets 924 may also be configured to provide a seal between adjacent floor panels 908 , configured to prevent the passage of liquids or gasses therethrough. They may be formed from material that is heat or fire resistant, to provide improved fire protection. In FIG. 10 , the gasket 924 may be seen to have a modified T-shape in cross-section, with a lower portion sized and configured to fit snugly between the spaced apart angle members 905 of the support rails 904 , and the crossrails 906 . The gaskets further include flanges extending to the sides and configured to receive the upper portions 911 of the floor panels 908 thereon. An upwardly extending portion of the gasket 924 rises between two adjacent floor panels 908 to terminate at a height approximately flush with an upper surface of the floor panels.
As disclosed in previous embodiments of the invention, the removable floor panel 908 includes an upper portion 911 having dimensions that are greater than a lower portion 913 , such that, when a floor panel 908 is appropriately positioned between support rails 904 on two sides and crossrails 906 on two sides, the lower portion 913 of the panel 908 lies between the upright portions of the support rails 904 and crossrails 906 , while the upper portion 911 of the panel 908 extends over the support rails 904 and crossrails 906 . Typically, the floor panels 908 are configured to rest on the flanges of the gaskets 924 , with the upper surface of the support and cross rails 904 , 906 bearing the weight of the panels 908 and any load thereon. Such an arrangement ensures a good seal between the panel 908 and the flange 924 . The lower portion 913 of the panels may comprise insulation and fire retardant material. The lower portion 913 of the floor panels 908 may be sized and configured to have a very snug fit in the space between the rails 904 , 906 to provide maximum sound and temperature insulation and fire protection.
Other embodiments of the invention may include panels configured to bear against lower portions of the support and cross rails, or may even be configured to fit entirely between the support and cross rails, with no part of the panel extending over the rails.
As shown in FIGS. 10 through 12 , the floor panels 908 may be affixed in position by threaded fasteners 918 that engage threads in the opening 930 of the spacer 922 of the support rails 904 . The floor panel 908 includes a fastener recess 919 at each corner thereof. The fastener recess 919 defines a shoulder 928 , against which a head of the threaded fastener 918 bears to maintain the floor panel 908 in position. A fastener 918 is provided at each corner of the floor panel 908 , and each fastener 918 bears against the shoulders 928 of four adjoining removable panels 908 . A fastener recess cap 920 is configured to fit in the fastener recesses 919 of four adjoining floor panels 908 , and to cover the respective fastener 918 .
As is most easily visible in FIGS. 10 , 14 , and 15 , the floor system 900 includes deck support rails 934 , running generally parallel to the subfloor rails 912 , and the secondary framing member 909 . The deck support rails 934 include threaded spacers 938 , similar to the spacers 922 of the support rails 904 . Threaded rods 926 engage the threaded spacers 915 of the subfloor rails 912 at a first end and the threaded spacers 938 of the deck support rails 934 at a second end, supporting the deck support rails 934 a selected distance beneath the section 902 . Corrugated decking 932 , of a type commonly used in commercial construction to support concrete flooring, may be placed between deck support rails 934 . The corrugated decking 932 provides a barrier between floors, and it may be used as part of a plenum enclosure for HVAC.
Lighting fixtures, fire control sprinklers, and other utilities for the space beneath the floor system 900 of FIGS. 9-15 , such as a lower floor of the structure, may be affixed to the corrugated decking 932 or to the deck support rails 934 . Fire resistant paneling such as gypsum board may also be affixed to the underside of the corrugated decking 936 , or to the deck support rails 934 .
In manufacturing and assembling the floor system 900 , much of the system may be prefabricated and assembled prior to assembly in a structure. For example, the floor section 902 shown in FIG. 9 is an 8′×8′ prefabricated section, having 2′×2′ floor panels 908 installed therein. The prefabricated floor section 902 may include temporary removable panels 908 , which can be left in place until completion of construction at which time the temporary panels 908 are replaced with finished panels. Use of temporary floor panels 908 prevents damage to the finished panels during construction, and allows construction workers, painters, and finishers to work in floored spaces without the requirement of providing protection for finished flooring. When the temporary panels are removed, they may be reused in subsequent projects, thus providing additional savings to the manufacturer.
In assembling such a floor system, the secondary framing members 909 are provided with the connectors 910 pre-attached. Each section is lifted into place by a hoist or crane, and lowered onto the connectors 910 . Because of the configuration of the connectors 910 and the support rails 904 , the floor section 902 is provided with positive positioning in the X-axis. As may be seen in FIG. 9 , each connector 910 provides positioning for a support rail 904 from each of two adjoining panels 902 in an end-to-end configuration. By drawing the support rails 904 of a section 902 tightly against the ends of the support rails 904 of a previously installed section 902 , positive positioning in the Y-axis may be assured. After the section 902 is correctly positioned in the X- and Y-axes, the section is leveled through the use of shims or jacks, to bring the section into correct position in the Z-axis. When the section is correctly positioned in the Z-axis, the support rails 904 of the section 902 are affixed to the connectors 910 , to lock them permanently in position. This may be achieved by any of several known methods, including welding in place, the use of bolts passing through the support rails 904 and the connectors 910 , or any other acceptable method of attachment. Next, splice plates 914 are affixed in position between subfloor rails 912 of adjoining sections 902 , secondary crossrails 916 are then positioned and affixed to adjoining sections 902 , and removable floor panels 908 are placed in the spaces created thereby, between adjoining sections 902 . Threaded fasteners 918 and fastener recess caps 920 are installed as necessary to secure the removable floor panels 908 . From underneath the floor panels 902 , threaded rods 926 are affixed to the threaded spacers 915 of the subfloor rails 912 , and to the threaded spacers 938 of the deck support rails 934 . Corrugated decking 932 is then laid between the deck support rails 934 to enclose a space under the floor system 900 .
The total height H of the floor system 900 (see FIG. 14 ) above the surface of the secondary framing members is selected to be approximately equal to the height or thickness of a conventional steel and concrete floor of the type commonly used in hi-rise construction. In some cases a structure may include a combination of conventional flooring with the structurally-integrated flooring according to the principles of the invention. Because the heights are substantially equal, there is no requirement for ramps or height adjustment at transitions from one flooring to the other.
It will be understood that, while the embodiment of the invention described with reference to FIGS. 9-15 is shown having particular selected dimensions, the dimensions of the sections 902 , the spacing of the rails 904 , 906 , 912 , 916 , and 934 , the dimensions of the panels 908 , and other dimensions and parameters of the system are selectable according to the requirements of a given application, or preferences of the user.
In a conventional building, an elevated floor system of the type described in the background section of this document is installed on top of an existing floor. The elevated floor occupies a space above the floor, and is not part of the building structure. The accessible space provided by such an elevated floor is that space between the panels that form the surface of the elevated floor and the upper surface of the solid floor deck. In the structurally integrated accessible floor system of the embodiments of the invention described herein the solid floor deck is not needed. The removable panels provide access to the space beneath the grid and between the individual secondary framing members. In prior floor structures, this space is inaccessible and wasted. Because the structural support grid of the present invention spans the secondary framing members, the space beneath is unobstructed, providing simplified access for pulling cables, laying conduit, ducting, and pipe. The cost of the floor system disclosed herein is significantly mitigated by several factors. A conventional structural floor is not required, and the floor system is essentially the same height as a conventional structural floor, obviating the need for ramps in areas where conventional floors adjoin the floor system. Because the floor system does not add height per story to the final building structure, there will be a savings in building materials, and a savings in operating costs over those of a similar building using accessible floors according to the prior art. Also, because the space under the floor system is unencumbered by pedestals, feet, or other support devices, the floor system has improved flexibility and changeability. Pulling cable, laying conduit and pipe, and installing ducting are all simplified. The labor costs and down time costs are reduced during changeovers. This floor system would also allow the incorporation of, and relocation of, egress lighting in the floor system, as a part of the gasket systems, or the vertices of the panels, for example. The gaskets may also be configured to allow the passage of gas by incorporating perforations in the gaskets.
An additional cost savings over conventional construction methods is realized by the reduction in structural weight provided by the implementation of an embodiment of the invention. Flooring manufactured according to the principles of the invention has a per square foot weight of less than half that of conventional high-rise flooring. Such a weight savings can exceed 20 to 30 pounds per square foot, without reducing the weight bearing capacity of the floor. This savings translates to a reduction in the costs of bringing construction materials to a construction site, the costs of assembling a structure, the mass and cost of materials required to support a structure, and finally, affords the architect structural options that were heretofore unavailable due to the weight of the structure.
Advantages of the use of a sub floor space as a plenum for HVAC have been known previously. However, because of the inaccessibility of that space in conventionally constructed buildings, or the cost of conventional removable flooring systems, the associated effort and expense of employing sub floor spaces as plenums have outweighed the benefits, in most cases. With the implementation of the principles of the invention, the costs are much reduced. Sub floor spaces may be easily partitioned such that large areas of a floor may have pressurized, conditioned air, to be accessed as desired. Accordingly, ventilation may be inexpensively modified to suit varying needs and preferences, simply by exchanging floor panels with panels having the desired configuration. By the same token, return plenums having negative pressure may also be configured inexpensively. The need for expensive air ducting and channeling may be significantly reduced. All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, are incorporated herein by reference, in their entirety.
From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. | A floor system for a building that includes primary and secondary structural supports, a grid attached to the supports, and a plurality of panels removably mounted in the grid to provide access to the space below the panels and the grid. The floor system replaces conventional permanent structural floors, and provides ready access to the underlying space, which would otherwise be inaccessible in a conventional floor. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of copending U.S. application Ser. No. 791,778 filed Nov. 4, 1991, now U.S. Pat. No. 5,189,689, which, in tern, is a continuation of U.S. application Ser. No. 572,392, filed Aug. 27, 1990, now U.S. Pat. No. 5,077,778.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of medical radiography; and more particularly to means for positively identifying the exposure side or front side of an X ray film.
2. Description of the Prior Art
A medical radiograph is the X ray image of some part of the body produced by an X ray beam originating from an X ray tube. The X ray beam passes first through the body and then through an X ray film cassette which is a light-proof, flat box of rigid construction. It is typically comprised of a base with a central recess to receive the film, and a cover joined to the base by hinges and containing latches permitting it to be opened and securely closed when a film is loaded. In order to diminish the X ray dose required to obtain a proper exposure of the film the inside surfaces of the cassette are lined with "intensifying screens" which sandwich the film between them. The X ray beam passing through the intensifying screens causes them to fluoresce and give off visible light which in turn exposes the film from both sides. Since the X ray film is much more sensitive to the visible light than to the X ray beam, most of the film exposure actually results from the induced light. The presence of the screens therefore allows the optimal film exposure to be achieved at significantly lower radiation doses than would otherwise be needed. Once the film is exposed, it is brought to the dark room, removed from the cassette and developed, causing the latent image to become visible. The radiograph is then ready for viewing and interpretation.
Since the film must be identified with pertinent information such as patient's name, date, etc., the cassette is also provided with what is herein called a "blocker". This blocker is generally comprised of two opposing strips of lead mounted on the inside surfaces of the cassette which shield the area of film between them from becoming exposed by either the X ray beam or its induced light. When the technologist is ready to develop the film, a card bearing the appropriate patient data is placed into a device which light-flashes the card, thereby projecting the data onto the unexposed area shielded by the blocker. The position of the blocking rectangle within the cassette is not constant and may vary with the manufacturer, individual X ray department, and even from one cassette type to another within the same department.
Apparatus and methods, including modifications of the film cassette for marking exposed X ray film or radiographs with patient data are disclosed, for example by U.S. Pat. Nos. 3,628,864, 3,703,272, 4,465,364, 4,510,392, 4,806,959, 4,383,329, 4,520,497, and 4,768,114.
When rendering a diagnosis from a radiograph it is necessary for the film reader to know which side of the body is being viewed. Since the body is generally symmetrical, right-sided structures are similar in appearance to left-sided structures except that they are mirror-images or reversals of one another. For example, an X ray image of a left foot if viewed from the back /f the exposed film will look like a right foot. Since radiographs are typically transparent and can be viewed from either side, it is therefore possible for X ray images of one side of the body to become confused with the other. For this reason when a medical radiograph is performed of some part of the body it is customary for the technologist to affix and X ray opaque "R" or "L" marker on the cassette cover adjacent to the part being X-rayed to indicate which side of the body is represented on the film. Not infrequently however, the technologist places the wrong marker on the cassette or for one reason or another the marker is not visible on the film, being either obscured or omitted, so that the technologist is required to mark the film after it is developed, using an adhesive label, wax pencil, ink, or even scratch marks. The incidence of incorrect or absent right/left marking due to human error is quite substantial, reportedly as high as 30%. If a film is improperly marked and the physician interpreting the film recognizes the error he will often try to locate the technologist who performed the study to obtain clarification. When the question cannot be resolved in this manner, the patient may be recalled for a repeat examination which involves time, inconvenience, expense and additional radiation exposure. Furthermore, if the error should go undetected, inappropriate medical treatment may be the result.
Since the primary cause of this right/left confusion stems from the fact that the film is transparent and may be viewed from the front (exposure side) or the back, identifying the front side of the film for the viewer will prevent the inadvertent viewing of the film from the wrong side and thereby permit ready determination of which side of the body is represented thereon.
There is no means described in the prior art for permanently modifying the film cassette to expressly indicate the exposure side of the film, positively and regardless of the direction of exposure.
SUMMARY OF THE INVENTION
The present invention provides an X ray film cassette with a permanent marking means for identifying the side of the radiographic film that faced the X ray tube during exposure. Such identification does not require any action by the X ray technologist, eliminating the element of human error. In a preferred embodiment, the working means is comprised of chirally asymmetric X ray opaque and/or light-opaque letters or markings permanently mounted in the film cassette.
Generally stated, markers are permanently mounted in the film cassette, providing the cassette with means for marking the X ray film during exposure with an image indicating the side of the film which faced the X ray tube during exposure.
In one aspect, the invention provides a radiographic film cassette for exposing a sheet of film to X rays projected along an X ray path by an X ray tube. The cassette includes a cover having an inner surface defining a recess for receiving the film sheet. A base having an inner surface is adapted to close upon the cover, securing the film sheet. The cassette has a &irst intensifying screen immovably disposed within the recess between the film sheet and the inner surface of the cover. A first marker is permanently fixed to the first intensifying screen and adjacent to the film to intersect a first portion of the X ray path during exposure. The first marker is chirally asymmetric and light opaque. A second marker is permanently fixed to the second intensifying screen adjacent to the film for intersecting a second portion of the X ray path. The second marker is light opaque, has external dimensions greater than the first marker and is so situated within the X-ray path that the first portion is overlapped by the second portion. The film sheet, upon exposure, bears a composite image of both the first and second markers. Optionally, the first and second marker are formed by removing a part of their respective intensifying screens. Alternatively the second marker is chirally asymmetric and light opaque, and the first marker is light opaque and has external dimensions greater than the second marker.
In addition, the invention provides an apparatus for installing a plurality of light-opaque markers on active sides of a plurality of intensifying screens disposed in an X ray film cassette, comprising; first and second markers, each being light-opaque and at lest one being chirally asymmetric; first and second applique sheets carrying the first and second markers, respectively, each of the applique sheets having an adhesive surface in contact with an anti-stick protective sheet, adapted for removal to unmask adhesive thereon; and spacing means comprising a spacer sheet having first and second planar surfaces provided with adhesive adapted for temporary contact with the first and second applique sheets, respectively, to thereby form a marker installation assembly; whereby disposition of the marker installation assembly on an active side of one of the intensifying screens with the adhesive surfaces unmasked is operative, upon closing the cassette, to adhesively secure the applique sheets to the intensifying screens in an aligned condition.
In use, the invention provides information concerning identification of the X ray path leading to exposure of the film sheet, which positively identifies the exposure side or front of the film. The information is provided by means which are user friendly and virtually eliminate the element of human error. Positive identification of the side of the film sheet facing the X ray tube during exposure permits more accurate diagnosis and results in fewer repeat examinations, thereby reducing the attendant inconvenience, expense and total radiation exposure to the population at large and improving the quality of medical care. Additionally, the information is copied to reproductions of the film.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more fully understood and further advantages will become apparent when reference is made to the following detailed description of the preferred embodiment of the invention and the accompanying drawings, in which:
FIG. 1 is an exploded view of an X ray film cassette;
FIG. 2 is a view of the inside of an open cassette equipped with stand-alone light-opaque markers;
FIG. 3 is an exposure-side view of an X ray film;
FIG. 4 is a view from the back of an X ray film;
FIG. 5 is an exploded view of apparatus for installing light-opaque markers on intensifying screens; and
FIG. 6 is a side view of the apparatus shown in FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2 of the drawings, there is shown an X ray film cassette 2 having molded cover 4 of aluminum, plastic, or other suitable material which is transparent to X rays and which is of rigid construction. Cover 4 has a flat inner surface 6 and upstanding flanges 8 encompassing the periphery of surface 6 to provide a recess for receiving a sheet of film 9. One or more hinges 10 are mounted along one of the flanges for attaching a base 26. A first intensifying screen 14 having an active surface 14a comprising a fluorescent material is attached to the inner surface 6. The first intensifying screen 14 is provided with a rectangular cutout 16 along one edge to receive X ray opaque blocking rectangle 20. Typically, blocking rectangle 20 comprises lead sheet of approximately 1 inch by 3 inches. A molded base 26 is formed of aluminum, plastic or other suitable material which is of rigid construction. Base 26 has a flat inner surface 28 and upstanding flanges 30 encompassing the periphery of surface 28 to provide a recess for receiving film sheet 9. Flange 30 is connected along one side to hinges 10. A foam pad 32 attached to the inner surface 28 of base 26 carries a second intensifying screen 34 having an active surface 34a comprising a fluorescent material. The second intensifying screen 34 has a cutout 36 provided to receive a second blocking rectangle 40. Typically, blocking rectangle 40 comprises lead sheet of approximately 1 inch by 3 inches. A sheet of lead 31 may be interposed between pad 32 and inner surface 28. Typically, cutout 36 and blocking rectangle 40 are identical to their respective counterparts 16 and 20 in cover 4 and are arranged so that the blocking rectangles 20 and 40 are stacked one over the other when the cassette 2 is closed.
First marker 60 and second marker 58 are located on the inner surfaces of intensifying screens 14 and 34, and generally along the edge thereof. Markers 60 and 58 are comprised of light-opaque material, such as black ink, paint, printed decal or similar marking, or X ray opaque lead foil. Marker 60 is chirally asymmetric. Chiral asymmetry provides a marker with a mirror image that is different from itself. Preferably, marker 60 comprises a symbol that expressly indicates the front or exposure side of the film, such as "F", "FRONT", VIEWING SIDE, TUBE SIDE, EXPOSURE SIDE, etc., since film 9 is normally viewed from the exposure side. Letters such as B, C, D, etc., and almost any word or sequence of words or letters in which the mirror image is different are chirally asymmetric and can be utilized. On the other hand, isolated letters such as "A", "O", "I", "T" and words such as "XIX", by virtue of their chiral symmetry would not be suitable. Cutting away or removing a portion of the intensifying screen in the desired shape would have the same effect. The dimensions of marker 58 are greater than the dimensions of marker 60. Markers 58 and 60 are oriented such that they line up one over the other when cassette 2 is closed, and marker 60 reads properly if viewed through cover 4.
Alternatively the second marker 58 is chirally asymmetric and light opaque, and the first marker 60 is light opaque and has external dimensions greater than the second marker. As a further alternative, markers 60 and 58 are cut out from their respective intensifying screens 14 and 34.
A radiograph of a left foot exposed in the usual way, through the cover of the cassette, is shown in FIGS. 3 and 4. When viewed from the front or exposure side of film 48, as shown in FIG. 3, marker image 44 is readable and the anatomy of the foot is also displayed in the correct orientation. Conversely, when film 48 is viewed from the back side, as shown in FIG. 4, the orientation of the anatomy is reversed, making it appear like a right foot, but the marker image 44 is also reversed, warning that the view is from the back side of film 48. Blocking rectangle image 46 is also shown in the figures.
Shown in FIGS. 5 and 6 is an apparatus 90 to facilitate installation of light-opaque markers 58 and 60 in cassette 2, the apparatus being about 1/8 inch in thickness. Apparatus 90 comprises a marker installation assembly 91 and anti-stick protective sheets 122 and 124. Applique 116 comprises light-transparent or translucent sheet 102, light-opaque marker 60, and permanent, adhesive coating 110, such as a pressure sensitive adhesive. Similarly, applique 114 comprises light-transparent or translucent sheet 104, light-opaque marker 58, and permanent, adhesive coating 120. Preferably, the adhesive coatings 110 and 120 exhibit clarity and resistance to ultraviolet and X ray aging, such as but not limited to, polyvinyl ethyl ether, polyisobutylene, or acrylate copolymer based coatings. The sheets 102 and 104 are composed of a member selected from the group consisting of cellophane, polyvinyl chloride, polyester, polyethylene, polypropylene, cellulose acetate and similar films. The adhesive coating 110 and 120 are temporarily protected by the anti-stick protective sheets 122 and 124 respectively. The protective sheets 122 and 124 are comprised of paper or similar web material having anti-stick coatings, such as cured dimethyl silicone or wax. These anti-stick protective sheets 122 and 124 have significantly lower surface energy than the surface tension of the adhesive coatings 110 and 120, and will therefore separate easily from the adhesive coatings. Typically the surface energy of the anti-stick protective sheets 122 and 124 is less than about 80%, preferably less than about 50%, more preferably ranges up to 25% of the surface tension of the adhesive coatings. Spacer 106 is comprised of a disposable material such as paper, cardboard, or foam pad, and the spacer has both faces covered with adhesive coatings 112 and 118. The adhesive coatings 112 and 118 have surface tensions significantly greater than the surface energies of appliques 114 and 116 respectively, and are thereby adapted to temporarily hold the appliques. Typically the surface tension of the adhesive coatings 112 and 118 is greater than about 125%, preferably greater than about 200%, more preferably ranges above 400% of the surface energy of the appliques 114 and 116.
In use of the apparatus 90, protective sheets 122 and 124 are stripped from marker installation assembly 91 and the exposed adhesive surface 120 is pressed against and along the periphery of the active surface 34a of the screen 34 disposed in open cassette 2, until firmly secured. Fully closing and reopening cassette 2 causes applique 116 to permanently affix to the active surface 14a of the screen 14, and the spacer 106 to separate at one of its adhesive surfaces 112 or 118, permitting removal and disposal of the spacer 106. Appliques 114 and 116 are permanently transferred to their respective intensifying screens 34 and 14, and markers 58 and 60 are then lined up exactly one over the other. The above described apparatus represents the preferred manner of installing markers on intensifying screens. Optionally, a single light-opaque marker having an adhesive surface is manually attached to either intensifying screen.
The invention has been described in detail with particular reference to the preferred embodiments thereof, but it will be understood that additional variations and modifications may suggest themselves to one skilled in the art, all falling within the scope of the invention as defined by the subjoined claims. | The present invention provides an X ray film cassette with a permanent marking means for identifying the side of the radiographic film that faced the X ray tube during exposure. Such identification does not require any action by the X ray technologist, eliminating the element of human error. The marking means is comprised of chirally asymmetric X ray opaque and/or light-opaque letters or markings permanently mounted in the film cassette to intersect overlapping portions of an X ray path projected during exposure. | 0 |
TECHNICAL FIELD
The present invention relates to a backup acceleration signal generating apparatus, and more particularly to an apparatus for use in a vehicle having an automatic transmission system controlled in accordance with the amount of the operation of an accelerator pedal. Specifically a backup acceleration signal is generated showing the amount of operation of an accelerator pedal which is used instead of an actual acceleration signal showing the amount of operation of an accelerator pedal at each instant. This backup signal is used when the generator for producing the actual acceleration signal breaks down or malfunctions.
BACKGROUND OF THE INVENTION
In the case of a vehicle provided with an automatic transmission system controlled in response to the amount of operation of an accelerator pedal, the control of the vehicle during driving may become difficult when the actual acceleration signal representing the amount of operation of the accelerator pedal at each instant cannot be obtained correctly because of trouble with an acceleration sensor or the like. To eliminate this problem, there has been proposed a backup system in which a signal representing a predetermined fixed amount of operation of the accelerator pedal is used instead of the actual acceleration signal when trouble arises with the acceleration sensor (Japanese Patent Application Public Disclosure No. Sho 60-75735).
The backup signal of the proposed system is of fixed value and there is thus no problem in the case where the vehicle continues to run at a given speed. However, it becomes impossible to stop the vehicle, even when the brake pedal is depressed by the driver. The engine speed may become extremely high when the transmission is shifted to neutral. Furthermore, when, for example, the backup acceleration signal is used in place of the acceleration signal when the vehicle is stopped, a very dangerous condition may arise in which the vehicle will start independently of the driver's intention.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved backup acceleration signal generating apparatus for vehicles which eliminates the disadvantages of the prior art described above.
It is another object of the present invention to provide a backup acceleration signal generating apparatus which is capable of producing a backup acceleration signal matched to the driving condition of the vehicle.
It is a further object of the present invention to provide a backup acceleration signal generating apparatus which is capable of producing an appropriate backup acceleration signal matched to the operating condition of a brake system of the vehicle.
It is a still further object of the present invention to provide a backup acceleration signal generating apparatus for an automatic transmission system, which is capable of providing a backup acceleration signal in such a way that the vehicle can be prevented from starting independently of the driver's intention when using the backup acceleration signal.
According to the present invention, in an apparatus for generating a backup acceleration signal for a vehicle having an automatic transmission controlled in accordance with the amount of operation of an accelerating member, the amount of acceleration represented by the backup acceleration signal is determined in accordance with the operating condition of the vehicle and is sufficiently low that it cannot start the vehicle.
As a detector for detecting the operating condition of the vehicle, there is provided means for producing a brake signal showing the operating/inoperating state of the brake system of the vehicle. The apparatus further comprises a first signal generating means for providing a first signal representing an amount of acceleration by which the vehicle cannot be started in the case where the brake system is in an operating state. This signal makes it possible to prevent the vehicle from being started upon the application of the backup acceleration signal at the time the braking power is effected. When the vehicle is running, a second signal representing a prescribed amount of acceleration is produced, which is capable of maintaining the vehicle running. When it is detected from the brake signal that the brake system has changed from its operating state to its inoperative state, there is produced a third signal which indicates an acceleration magnitude that changes from a low amount not capable of starting the vehicle to a large amount capable of maintaining the vehicle running.
Thus, in the case where trouble arises with the acceleration sensor, if the brake system is in the operating state, the first signal is used for controlling the operation of the vehicle. If, for example, the braking power is released in this case, the vehicle can start under application of the third signal, enabling the vehicle to be started and accelerated. Thus, since the backup acceleration signal is determined in accordance with the operating condition of the braking system, it becomes possible to provide backup for smooth stopping and starting operation of the vehicle.
In another backup acceleration signal generating apparatus according to the present invention, the apparatus comprises determining means for discriminating whether or not the automatic transmission system is in a gear set state and the clutch is in a disengaged state, produces a backup acceleration signal representing a low acceleration magnitude which is not capable of starting the vehicle when the automatic transmission system is in a gear set state and the clutch is disengaged. In this apparatus, the low acceleration magnitude may be set to correspond to the release condition of the accelerator pedal. Therefore, even when the backup acceleration signal is employed in the condition stated above because of some trouble in the acceleration detection system, starting of the vehicle independently of the driver's intention can be prevented. Thus, a highly safe backup system can be provided since the vehicle will not start automatically even if the acceleration detection system malfunctions when the driver is not in the vehicle.
The invention will be better understood and other objects and advantages thereof will be more apparent from the following detailed description of preferred embodiments made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing an embodiment of an automatic transmission system for vehicles employing a backup acceleration signal generating apparatus according to the present invention;
FIG. 2 is a detailed block diagram of a first unit shown in FIG. 1;
FIG. 3 is a detailed block diagram of a control unit shown in FIG. 1;
FIGS. 4A to 4F are waveform diagrams of signals in FIG. 3;
FIG. 5 is a block diagram showing a modification of the backup acceleration signal generator shown in FIG. 1; and
FIGS. 6A and 6B are flowcharts showing a control program executed in the device shown in FIG. 5.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 shows a block diagram of one embodiment of a vehicle automatic transmission system equipped with a backup acceleration signal generating apparatus according to the present invention. The automatic transmission system has an automatic transmission mechanism 4 operated in accordance with data showing the amount of operation of an accelerator pedal 2 and data showing the position of a select lever 3a of a selector 3. The accelerator pedal 2 is connected with a potentiometer 5 by which the amount of operation of the accelerator pedal 2 is converted into a voltage signal. A detection voltage VD from the potentiometer 5 is applied to an acceleration signal generator 6 which produces an actual acceleration signal A showing the amount of operation of the accelerator pedal 2 at each instant. The actual acceleration signal A is supplied through a first switch 7 to the automatic transmission mechanism 4 having a gear transmission 4a and a clutch 4b.
The selector 3 is connected with a position sensor 8 for producing a position signal SL showing the position of the select lever 3a and the position signal SL is supplied to the automatic transmission mechanism 4, which is of wellknown design, and to a backup acceleration signal generator 100 according to the present invention.
The backup acceleration signal generator 100 is for generating a backup acceleration signal BA which is used instead of the actual acceleration signal A when the actual acceleration signal A cannot be obtained normally from the acceleration signal generator 6. The backup acceleration signal BA is supplied to the first switch 7 which is controlled by a switch control signal S 1 from a trouble detecting circuit 9. The trouble detecting circuit 9 is responsive to the actual acceleration signal A and discriminates whether or not the actual acceleration signal A is normally produced from the acceleration signal generator 6. The switch control signal S 1 is produced from the trouble detecting circuit 9 when an abnormal condition of the actual acceleration signal A is detected thereby, and the first switch 7 is switched over from the state shown by the solid line to the state shown by the broken line when an abnormal condition is detected.
More specifically, the actual acceleration signal A is selected by the first switch 7 and is supplied to the automatic transmission mechanism 4 when the actual acceleration signal A is produced normally. In contrast, the backup acceleration signal BA is selected by the first switch 7 and is supplied to the automatic transmission mechanism 4 when the actual acceleration signal A is not produced normally.
The automatic transmission mechanism 4 is responsive to the position signal SL and the signal selected by the first switch 7 and the required gear shift operation is carried out.
The backup acceleration signal generator 100 has a first unit 10 for producing a first backup acceleration signal BA 1 and a second unit 11 for producing a second backup acceleration signal BA 2 . The first and second backup acceleration signals BA 1 and BA 2 are applied to a second switch 12 and one or the other of the two signals BA 1 and BA 2 is selected as the backup accelerator signal BA by the second switch 12. The switching operation of the second switch 12 is controlled by a switch control signal S 2 , which is produced by a control unit 13 to which the switch control signal S 1 and the position signal SL are supplied.
An explanation of the first unit 10 will now be given in conjunction with FIG. 2. The first unit 10 has a first signal generating unit 21 for producing a first signal U 1 corresponding to the actual acceleration signal A for the case where the accelerator pedal 2 is released (e.g. the amount of the acceleration is zero), and a second signal generating unit 22 for producing a second signal U 2 showing a predetermined amount of acceleration necessary for maintaining the vehicle running.
In this embodiment, the second signal generating unit 22 is arranged in such a way that a signal representing the backup amount of acceleration predetermined in accordance with the position of the selector 3 is produced as the second signal U 2 in response to the position signal SL. That is, a fixed amount of acceleration determined in accordance with the position of the selector 3 is used for the backup operation using the second signal U 2 . As a result, it is possible to realize fine backup operation matched to the position of the selector 3.
The first and second signals U 1 and U 2 are forwarded to a switching element 23, whose switching operation is controlled by a brake signal BK produced by a brake sensor 17 shown in FIG. 1. The brake sensor 17 is connected with a brake system 16 and detects whether or not the brake system 16 is in the operating condition. The brake signal BK shows the result of this detection. The switching element 23 is switched over as shown by the broken line in FIG. 2 in response to the brake signal BK when the brake system 16 is providing braking power, and the first signal U 1 is selected by the switching element 23. On the other hand, the switching element 23 is switched over as shown by the solid line in FIG. 2 in response to the brake signal BK when the brake system 16 does not provide braking power, and the second signal U 2 is selected by the switching element 23. The selected signal from the switching element 23 is applied to a selecting unit 24.
A third signal generating unit 25 is responsive to the brake signal BK and produces a third signal U 3 indicating an amount of acceleration which changes with the passage of time after the braking power applied to the vehicle by the brake system is released from a small amount not capable of starting the vehicle to a predetermined larger amount. The small amount mentioned above may be the amount of acceleration indicated by the actual acceleration signal A in the case where the accelerator pedal 2 is released (not depressed).
The signal generator 25 generates an initial amount signal E 1 showing the small amount or the start amount mentioned above, and the initial amount signal E 1 may be an upper limit amount above which the acceleration is capable of making the vehicle start. The initial amount signal E 1 is applied to a switching element 26 to which the first backup acceleration signal BA 1 from the selecting unit 24 is applied, and the switching element 26 is also switched over in response to the brake signal BK. The switching element 26 is switched over to the state shown by the solid line to select the first backup acceleration signal BA 1 when the braking power is not provided to the vehicle by the brake system 16. On the other hand, the switching element 26 is switched over to the state shown by the broken line to select the initial amount signal E 1 when the braking power is effected to the vehicle by the brake system 16. The output from the switching element 26 is applied to a first terminal 27a of a calculating unit 27.
The calculating unit 27 functions to repeatedly carry out a calculation for adding an increment amount ΔA of acceleration shown by a signal applied to a second terminal 27b of the calculating unit 27 to the amount of acceleration shown by the signal applied to the first terminal 27a at predetermined time intervals. A step amount calculating unit 28 is responsive to the position signal SL and the signal showing the increment amount ΔA of acceleration is produced as a step amount signal ST, which is applied to the second terminal 27b. The increment amount ΔA shown by the stepaamount signal ST is determined in accordance with the position of the selector at each instant. The output from the calculating unit 27 is produced as the third signal U 3 , which is supplied to the selecting unit 24.
The selecting unit 24 compares the magnitudes of the signal from the switching element 23 and the third signal U 3 , and outputs the smaller of the two signals as the first backup acceleration signal BA 1 at that time.
The operation of the first unit 10 will now be explained.
Both of the switching elements 23 and 26 are switched over as shown by the solid lines when no braking power is effected on the vehicle by the brake system 16. Therefore, the second signal U 2 is selected by the switching element 23 and is supplied to the selecting unit 24. On the other hand, in the third signal generating unit 25, the calculating unit 27 receives through its second terminal 27b the step amount signal ST showing the increment amount ΔA of acceleration and the first backup acceleration signal BA 1 is applied through the switching element 26 to the first terminal 27a of the calculating unit 27.
Accordingly, when the result of adding the increment amount ΔA shown by the step amount signal ST to the amount of acceleration shown by the first backup acceleration signal BA 1 is smaller than that shown by the second signal U 2 , the third signal U 3 is selected by the selecting unit 24 and is output as the updated first backup acceleration signal BA 1 . Thus, the amount of acceleration shown by the third signal U 3 is stepwisely increased in the manner indicated above, and the second signal U 2 is derived as a first backup acceleration signal BA 1 when U 3 >U 2 . As will be understood from the above explanation, the magnitude of the third signal U 3 does not exceed the magnitude of the sum of the second signal U 2 and the step amount signal ST. That is, when the brake system 16 is in an inoperative state, the second signal U 2 is output as the first backup acceleration signal BA 1 in the stationary state of the first unit 10 and the vehicle running speed is maintained in accordance with the position of the selector 3.
On the other hand, both of the switching elements 23 and 26 are switched over as shown by the broken lines when the braking power is effected on the vehicle by the brake system 16. Thus, the first signal U 1 is selected by the switching element 23 and is applied to the selecting unit 24. In the third signal generating unit 25, the initial amount signal E 1 is selected by the switching element 26 instead of the first backup acceleration signal BA 1 and is applied to the first terminal 27a of the calculating unit 27. Therefore, the maximum magnitude of the third signal U 3 is equal to the result of the addition of the initial amount signal E 1 and the step amount signal ST. As a result, the first backup acceleration signal BA 1 becomes equal to the first signal U 1 , so that the vehicle cannot start, and the stopped state of the vehicle can be maintained by the brake system 16.
In the condition described above, when the braking power provided by the brake system 16 is released, the switching elements 23 and 26 are switched over as shown by the solid lines. The switching operation causes the third signal generating unit 25 to produce a third signal U 3 which is equal to the sum of the amount of acceleration of the step amount signal ST and that of the initial amount signal E 1 . Since U 3 <U 2 in this case, the third signal U 3 is selected as the first backup acceleration signal BA 1 by the selecting unit 24 and the first backup acceleration signal BA 1 from the selecting unit 24 is applied through the switching element 26 to the first terminal 27a of the calculating unit 27. As described above, the output from the calculating unit 27 is stepwisely increased with the passage of time and the third signal U 3 is output as the first backup acceleration signal BA 1 until the relationship of U 3 >U 2 is established. Consequently, the magnitude of the first backup acceleration signal BA 1 is stepwisely increased to the magnitude of the second signal U 2 , and the control for starting the vehicle is smoothly carried out after the braking power effected by the brake system 16 is removed.
As will be understood from the above description, when the value of ΔA is set at more than U 2 -U 3 at the time the braking power effected by the brake system 16 is removed, it is possible to obtain two kinds of backup acceleration signals: one for maintaining the vehicle running when the brake system 16 is in operative condition and another of a small level insufficient to make the vehicle start.
Referring to FIG. 1, the second unit 11 is for
producing the second backup acceleration signal BA 2 showing a small fixed amount of acceleration (e.g. corresponding to the released condition of the accelerator pedal 2) of a level incapable of causing the control operation for starting the vehicle in the automatic transmission mechanism 4. The second backup acceleration signal BA 2 is selected by the second switch 12 instead of the first backup acceleration signal BA 1 when the control unit 13 detects that the gear of the automatic transmission mechanism 4 is set and the clutch is disengaged.
An explanation of the control unit 13 will now be given in conjunction with FIG. 3. The control unit 13 has a vehicle speed sensor 31 for producing a vehicle speed signal V showing the speed of the vehicle, a gear position sensor 32 for producing a gear position signal GP representing the position to which the gear of the transmission 4a is shifted and a clutch sensor 33 for producing a clutch signal CL representing the engaged/disengaged state of the clutch 4b in the automatic transmission mechanism 4. The vehicle speed signal V, the gear position signal GP and the clutch signal CL are applied to a detecting unit 34 to which the switch control signal S 1 is applied. The detecting unit 34 is responsive to the switch control signal S 1 and discriminates whether or not the gear is set in the transmission, the clutch is disengaged and the vehicle speed is zero at the time the level of the switch control signal S 1 changes from low to high. The level of the output signal DS from the detecting unit 34 is latched at high level when the gear is set in the transmission, the clutch is disengaged and the vehicle speed is zero.
The control unit 13 further comprises a memory unit 35 which is responsive to the switch control signal S 1 and the position signal SL and stores the position of the select lever 3a at the time the level of the switch control signal S 1 changes from low to high. Output data MD showing the content of the memory unit 35 is applied to a discriminating unit 36 to which the position signal SL is also applied. The discriminating unit 36 discriminates whether or not the position of the select lever 3a at that time is the same as the position indicated by the output data MD, and the level of the output signal CO of the discriminating unit 36 become high when the two positions are identical.
The output signals DS and CO are applied to an AND gate 37 and the output signal O 1 of the AND gate 37 is input to one input terminal of another AND gate 38. The switch control signal S 1 is input to a delay unit 39 for delaying the switch control signal S 1 by a predetermined time Δt and the delayed switch control signal S 1 is derived as a delay switch control signal SD 1 . The level of the delay switch control signal SD 1 is inverted by means of an inverter 40 and the inverted signal SD 1 is applied to one input terminal of an OR gate 41 having another input terminal to which the output signal from the AND gate 38 is input. The output signal O 2 from the OR gate 41 is input to another input terminal of the AND gate 38 and the output signal of the AND gate 38 is derived as the switch control signal S 2 .
The operation of the control unit 13 will be described with reference to FIGS. 4A to 4F. Assuming that the actual acceleration signal A becomes abnormal at t=t 1 , the level of the switch control signal S 1 changes from low to high (FIG. 4A) and the predetermined detecting operation is carried out by the detecting unit 34 in response thereto. If the gear of the transmission mechanism 4 is set, the clutch is disengaged and the vehicle speed is zero at time t 1 , the level of the output signal DS becomes high at the time t 1 as shown in FIG. 4C.
At the same time, the position selected by the select lever 3a at that time is stored in the memory unit 35 and the content of the position signal SL is compared with that of the output data MD. In this example, since the position of the select lever 3a is not changed from t 1 to t 3 , the level of the output signal CO is maintained at high level during this period (FIG. 4D). Consequently, the level of the output signal O 1 of the AND gate 37 becomes high at the time t 1 , causing the level of the one terminal of the AND gate 38 to become high.
On the other hand, the switch control signal S 1 is delayed by the time Δt by means of the delay unit 39 and the delay switch control signal SD 1 is derived therefrom (FIG. 4B). The inverted signal SD 1 from the inverter 40 is applied to the OR gate 41. Accordingly, the high level condition of the output signal O 2 is maintained at least until time t 2 , so that the level of the output of the AND gate 38, i.e. the switch control signal S 2 , becomes high when the level of the output signal O 1 is changed to high (FIG. 4F). The high level state of the output signal of the AND gate 38 is returned through the OR gate 41 to the other input terminal of the AND gate 38. Thus, the high level state of the output of the AND gate 38 can be maintained as long as the level of the output signal O 1 is high.
When the select lever 3a is manipulated to change its position at time t 3 , the level of the output signal CO changes from high to low. Accordingly, the level of the output signal O 1 also changes similarly (FIG. 4D). As a result, the level of the switch control signal S 2 changes from high to low at time t 3 . Since the level of the inverted signal SD 1 has already become low at this time, the low level state of the switch control signal S 2 is not changed even if the select lever 3a is returned to the former position after that time, for example, at time t 4 and the level of the output signal CO is changed to high (FIGS. 4D and 4F).
That is, since the level of the switch control signal S 2 changes to high when the level of the output signal DS become high, the second switch 12 is switched over as shown by the broken line in FIG. 1, enabling the second backup acceleration signal BA 2 to be derived as the backup acceleration signal BA. As result, even if the actual acceleration signal A becomes abnormal at the time when the gear of the transmission is set and the clutch is disengaged, the vehicle is safe from carrying out the vehicle starting operation in response to the application of the backup acceleration signal since the backup acceleration signal BA produced at this time corresponds to the actual acceleration signal when the amount of operation of the accelerator pedal 2 is zero.
Furthermore, when the selector 3 is manipulated by the driver, the backup condition using the second backup acceleration signal BA 2 , which is the backup state for when the driver is absent, is canceled and the backup of the system is attained by the use of the first backup acceleration signal BA 1 . After this, the backup state does not return to the backup state using the second backup acceleration signal BA 2 unless the necessary condition is satisfied. Thus, it is possible to carry out the backup operations for starting, running and stopping of the vehicle by the use of the first backup acceleration signal BA 1 .
In this embodiment, the backup system uses the first and second backup acceleration signals BA 1 and BA 2 . However, if desired, it is, of course, possible to arrange a backup system employing either one of backup acceleration signals BA 1 and BA 2 .
Functions the same as those of the backup acceleration signal generator 100 shown in FIG. 1 can be realized by using a microcomputer in which a predetermined control program is executed. FIG. 5 is a block diagram showing a backup acceleration signal generator 100' constituted differently from, but having functions corresponding to, the backup acceleration signal generator 100. The backup acceleration signal generator 100' comprises an interface circuit 101 receiving the brake signal BK from the brake sensor 17, the switch control signal S 1 and the position signal SL. The interface circuit 101 is connected through a bus 102 to a central processing unit (CPU) 103, a random access memory (RAM) 104 and a randomly memory (ROM) 105 in which a control program for performing the same functions as those of the generator 100 is stored. The result of the computation is derived from the interface circuit 101 as the backup acceleration signal BA.
Flowcharts showing the control program stored in the ROM 105 are shown in FIGS. 6A and 6B.
After the start of execution of the program, initialization is carried out and the operation moves to step 51 in which data necessary for the computation is read into and stored in the RAM 104. In step 52, discrimination is made as to whether or not a flag F 1 is set. The determination in step 52 becomes NO in the case of the first execution of step 52 after the initialization since the flag F 1 is reset by the initialization, and the operation moves to step 53. Data SEN showing the position of the select lever 3a at that time is set as SE in step 53 and the flag F 1 is set in step 54.
After this, the operation moves to step 55 in which discrimination is made as to whether or not the transmission is in its neutral position and the operation moves to step 56 in which a flag F 2 is reset when the result of the discrimination of step 55 is YES. If the discrimination of step 55 is NO, the operation moves to step 57 in which discrimination is made as to whether or not the clutch is in its engaged or ON condition. The operation moves to step 56 when the discrimination in step 57 is YES, and the operation moves to step 58 when the discrimination in step 57 is NO. Discrimination is made in step 58 as to whether or not the vehicle speed V is zero and the operation moves to step 56 when the vehicle speed is not zero. When the vehicle speed is zero, the discrimination in step 58 becomes NO and the operation moves to step 59, wherein data ACC showing the amount of acceleration for backup is set at zero acceleration state (o [%]). After this, the operation returns to step 51.
In summary, when all of the discriminations in steps 55, 57 and 58 become NO, in other words, when the gear is in a position other than neutral, the clutch is disengaged and the vehicle speed is zero, the content of data ACC is set to correspond to the case where the accelerator pedal is released. Consequently, in this case, the control operation for starting the vehicle is not carried out when the content of data ACC is provided as backup acceleration signal BA to the automatic transmission mechanism 4 instead of the actual acceleration signal A, and the backup operation can be safely performed. As will be understood from the foregoing description, the content of data ACC to be set is not limited to data showing the acceleration amount in the case where the accelerator pedal is released, but may be data showing any acceleration amount insufficient for starting the control operation for starting the vehicle.
In the case where the step 52 is executed again, since the flag F 1 has already been set in step 54, the discrimination in step 52 becomes YES and the operation moves to step 60. Discrimination is made in step 60 as to whether or not the flag F 2 is set. The discrimination in step 60 becomes NO for the first execution of step 60 and the operation moves to step 61, wherein discrimination is made as to whether or not the present position SE N of the select lever 3a is coincident with the position shown by data SE. When SE=SE N , the operation moves to step 59.
When the discrimination in step 61 is NO due to, for example, a change in the position of the select lever 3a, the operation moves to step 63 after the execution of step 62 for setting the flag F 2 . When the discrimination in step 60 is YES or after step 56 is executed, the operation moves to step 63.
Discrimination is made in step 63 as to whether or not braking power is applied to the vehicle by the brake system 16, i.e. whether the brake system is ON. When the result of the discrimination in step 63 is YES, the operation moves to step 64, wherein data ACC is set to zero, which represents no operation of the accelerator pedal, and returns to step 51. This means that the amount of acceleration for backup operation is set to zero.
When the result of the discrimination in step 63 is NO, the operation moves to step 65 wherein discrimination is made as to whether or not the selector 3 is in neutral position. When the result of the discrimination in step 65 is YES, the operation moves to step 66 wherein data ACMAX showing the maximum amount of acceleration for backup operation is set at a fixed amount ACCN. When the result of the discrimination in step 65 is NO, the operation moves to step 67 wherein discrimination is made as to whether or not the selector 3 is in the reverse (R) position. When the discrimination in step 67 is YES, the operation moves to step 68 wherein data ACMAX is set at a fixed amount ACCR. When the result of the discrimination in step 67 is NO, the operation moves to step 69 wherein discrimination is made as to whether or not the selector 3 is in the second (2nd) position. When the discrimination in step 69 is YES, the operation moves to step 70 wherein data ACMAX is set at a fixed amount ACC2. When the selector 3 is in the drive (D) position, the result of the discrimination in step 69 is NO and data ACMAX is set at a fixed amount ACCD in step 71, wherein ACCD<ACC2<ACCR<ACCN<0.
As will be understood from the foregoing description, when the brake system 16 is OFF, the content of data ACMAX showing the maximum amount of acceleration for backup operation is determined in one of steps 66, 68, 70 or 71 in accordance with the position of the selector 3 and the operation moves to step 72 thereafter.
In step 72, data ACC showing the acceleration amount for backup operation at that time is compared with data ACMAX showing the maximum amount of acceleration determined as described above, and the operation moves to step 73 when ACC≧ACMAX. The content of the data ACMAX is set as the content of data ACC in step 73 and the operation returns to step 51.
When the result of the discrimination in step 72 is NO, the operation moves to step 74 wherein discrimination is made as to whether or not the selector 3 is in the neutral (N) position. When the result of the discrimination in step 74 is YES, the operation moves to step 75 wherein data ΔA showing an increment amount of acceleration for backup operation is set at a value STN. When the result of the discrimination in step 74 is NO, the operation moves to step 76 wherein discrimination is made as to whether or not the selector 3 is in the reverse (R) position. When the result of the discrimination in step 76 is YES, the operation moves to step 77 wherein data ΔA is set at a value STR.
When the result of the discrimination in step 76 is NO, the operation moves to step 78 wherein discrimination is made as to whether or not the selector 3 is in the second (2nd) position. When the result of the discrimination in step 78 is YES, the operation moves to step 79 wherein data ΔA is set at value ST2. When the selector 3 is in the drive (D) position, the result of the discrimination in step 78 becomes NO, and data ΔA is set at a fixed amount STD in step 80. Thus, data ΔA is determined in one of steps 75, 77, 79 and 80 in accordance with the position of the selector 3 and the operation moves to step 81 thereafter.
The sum of ACC and ΔA is set as data ACC in step 81. That is, data ACC is increased by ΔA in step 81 and the operation moves to step 82 wherein discrimination is made as to whether or not ACC≧ACMAX. The result of the discrimination in step 82 becomes NO when ACC≦ACMAX and the operation returns to step 51 to repeat the operations described above. Thus, data ACC is increased by ΔA every program cycle and the result of the discrimination in step 82 becomes YES when ACC≧ACMAX. Accordingly, the value of data ACC is replaced by the value of data ACMAX as data ACC in step 83 when ACC≧ACMAX and the operation returns to step 51.
In summary, when the brake system 16 is OFF, the amount of acceleration for backup operation is a fixed value determined in accordance with the position of the selector 3. When the brake system 16 operates so as to change from its ON state to its OFF state, the amount of acceleration for backup operation is changed so as to stepwisely increase from zero to the fixed value determined in accordance with the position selected by the selector 3. In this case, the increment amount shown by data ΔA is determied by the position of the selector 3. | A backup acceleration signal generator for vehicles having, for example, an automatic transmission operating in response to a signal indicating the amount of acceleration, has a signal generator for producing a backup operation. The backup signal is too small to start the control operation for starting the vehicle and is applied to the automatic transmission in accordance with the braking condition of the vehicle or the operating condition of the automatic transmission. The apparatus supplies the backup signal to the automatic transmission when braking power is applied to the vehicle or the vehicle is in the parked condition, so that the vehicle is prevented from starting automatically when the backup operation starts due to the occurrence of an abnormality of the acceleration signal. | 5 |
[0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 62/107,041 entitled POST REINFORCEMENT and filed on Jan. 23, 2015, the entire contents of which are hereby incorporated by reference.
[0002] The present invention is directed to a post reinforcement, and more particularly, to a post reinforcement which can at least partially surround and reinforcement a post.
BACKGROUND
[0003] Posts and poles can be used in a variety of manners such as porch supports, fence posts, telephone/utility poles, and the like. The posts are often located outdoors, and in some cases are installed and set in cement foundations, for example foundations up to around three to four feet deep. When the post is made of wood or other materials susceptible to degradation, wear or rot, the post may lose structural integrity due to repeated exposure to moisture and natural forces, thereby putting the post at risk for failure.
[0004] Posts are typically most vulnerable to rotting at or just below ground level. In particular, when such posts are set in concrete, rain water typically collects on top of the concrete, thereby increasing the post's exposure to moisture at or just below ground level. In many cases, aside from a weakened portion at or near ground level, the remainder of the length of the post is structurally sound. Accordingly, reinforcement of the post at ground level may increase the useful life of the post as a functional support and help to avoid or postpone the costs associated with replacing the entire post.
SUMMARY
[0005] In one embodiment, the invention is a post reinforcement including a panel having a body portion and a stake portion. The post reinforcement further includes a first barb coupled to and extending away from the panel, wherein the first barb is generally positioned on a first side of the panel. The post reinforcement also includes a second barb coupled to and extending away from the panel, wherein the second barb is generally positioned on a second side of the panel opposite the first side.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a front perspective view of one embodiment of a post reinforcement;
[0007] FIG. 2 is a left side view of the post reinforcement of FIG. 1 , but showing an inwardly-angled stake portion;
[0008] FIG. 3 is a rear (interior) view of the post reinforcement of FIG. 1 ;
[0009] FIG. 4 is right side view of the post reinforcement of FIG. 1 ; and
[0010] FIG. 5 illustrates the post reinforcement of FIG. 1 secured to an embedded post.
DETAILED DESCRIPTION
[0011] With reference to FIGS. 1-5 , an embodiment of a post reinforcement 10 includes a center or main panel 12 and two opposed side panels 14 positioned an opposite ends of the main panel 12 . Each of the panels 12 , 14 is shown as a generally flat, rectangular piece of sheet-like material with a generally rectangular body or body portion 13 . The center panel 12 and each side panel 14 are set at angles to each other to define a cavity or receptacle 16 therebetween that is sized and shaped to receive a post or pole 15 ( FIG. 5 ) therein, such a wooden post. In the depicted embodiment, the panels 12 , 14 are roughly equally shaped and sized, and positioned at about 90° relative to the adjacent panel(s) such that the receptacle 16 has a generally square or rectangular cross-section, for example to receive a 4″×4″ post 15 .
[0012] Though the post reinforcement 10 is depicted with three total panels 12 , 14 , it should be understood that the post reinforcement 10 may include more panels, up to and including an amount sufficient to completely enclose the post 15 , if desired. Alternatively, the post reinforcement 10 can include fewer panels than those shown to abut fewer sides of the post 15 (for example, one of the depicted panels 14 could be omitted). It should be further understood that the panels 12 , 14 may take any shape, size, and relative orientation as appropriate to closely receive and/or fit about a particular target post 15 , including posts with any of a variety of polygonal and/or curved cross sections. In one embodiment, the post reinforcement 10 may include only a single curved panel, or more than one panel, to define a receptacle 16 with a generally semicircular or generally circular cross-section, for example to receive a cylindrical pole.
[0013] One or more of the panels 12 , 14 can have a stake portion 18 or portions 18 extending from a bottom 20 of the body portion 13 of the respective panel 12 , 14 . The stake portion 18 may be integrally formed with the panel 12 , 14 , or alternatively formed of a separate piece of material. When the post reinforcement 10 is installed on a post 15 , the stake portion 18 is driven downward between the post 15 and the surrounding support structure, substrate or surface 17 (e.g., the cement foundation, soil, etc.) as shown in FIG. 5 . Each stake portion 18 may taper to a point 22 , which may facilitate installation of the post reinforcement 10 by providing a penetrating point.
[0014] The post reinforcement 10 may be able to be pounded into place from above with a hammer, mallet, or the like, by concentrating the force of the blows to a small surface area (via the points 22 in one case) and driving the post reinforcement 10 into/below the surrounding support structure 17 . In the depicted embodiment, each of the three panels 12 , 14 includes a stake portion 18 , and each stake portion 18 has about the same size and shape. Alternately, the post reinforcement 10 may include stake portions 18 on fewer than all of the panels 12 , 14 , and/or different panels 12 , 14 may include stake portions 18 with different shapes and/or dimensions (length and/or width). Further alternately the post reinforcement 10 can include multiple stake portions 18 per panel 12 , 14 , and/or stake portions 18 with shapes different from the triangular shape of the depicted embodiment, for example jagged/serrated, W-shaped, U-shaped, square-shaped, trapezoidal, or any of a variety of other polygonal or curved forms.
[0015] In one embodiment one or more, or all, of the stake portions 18 may be angled slightly inward toward the receptacle 16 , or the stake portions 18 may be otherwise inwardly-biased and/or spring-loaded. For example, in one case each stake portion 18 is angled inwardly relative to the body 13 of the associated panel 12 , 14 by up to about 20° or less, or up to about 10° or less. Only the stake portion 18 associated with the main panel 12 in FIG. 2 is shown angled in this manner for illustrative purposes, although it should be understood the other stake portions 18 may be similarly angled. Accordingly, in this embodiment, to install the post reinforcement 10 onto a post 15 , the stake portion(s) 18 may need to be splayed slightly outwardly from their normal position (for example, into planar alignment with the body 13 of the panels 12 , 14 ), to allow the reinforcement 10 to receive the post 15 in the receptacle 16 . Thus, when the reinforcement 10 is positioned on the post 15 , the stake portions 18 are biased into the sides of the post 15 in a gripping fashion, and the points 22 may at least slightly initially penetrate into the post 15 . When the post reinforcement 10 is driven into the support structure 17 from above, the points 22 may further penetrate into the post 15 for a more secure installation.
[0016] One or more of the stake portions 18 may further include inwardly-oriented barbs 24 that project into/toward the receptacle 16 and/or outwardly-oriented barbs 26 that project outwardly from the stake portions 18 away from the receptacle 16 and toward the surrounding support structure 17 . In the depicted embodiment, the inwardly-oriented barbs 24 are positioned above the outwardly-oriented barbs 26 (i.e. the inwardly-oriented barbs 24 are positioned between the outwardly-oriented barbs 26 and body 13 of the panels 12 , 14 ), and the inwardly-oriented barbs 24 are larger in size, but this need not be the case. In embodiments with multiple stake portions 18 , each stake portion 18 need not necessarily include the same number and/or configuration of barbs 24 , 26 . When the post reinforcement 10 is installed on a post 15 , the inwardly-oriented barbs 24 anchor into the body of the post 15 , for example by fully or partially penetrating into the post 15 below ground level, thereby improving stability of the system. If the stake portions 18 are angled inwardly, this helps to drive the barbs 24 into the post 15 . The outwardly-oriented barbs 26 anchor into the surrounding support structure 17 , providing resistance against uprooting of the post reinforcement 10 once installed.
[0017] The barbs 24 , 26 may be set at a slight angle, for example up to about 30° or less, or up to about 15° or less, relatively to a main portion/body portion of the associated stake portion 18 . In the depicted embodiment, the barbs 24 , 26 are generally triangular in shape, and are integrally formed with the stake portions 18 . However it should be appreciated that the barbs 24 , 26 may alternately be external components attached to the stake portions 18 , and that the barbs 24 , 26 may be formed in any of a variety of shapes, for example jagged/serrated, W-shaped, U-shaped, square-shaped, trapezoidal, or any of a variety of other polygonal or curved forms.
[0018] The post reinforcement 10 may include one or more strike surfaces 28 to facilitate installation thereof. In one embodiment, the strike surface 28 takes the form of a flange positioned at or proximate to the top 30 of the body 13 of one or more of the panel 12 , 14 . The strike surface 28 may be a flange or surface that extends generally perpendicularly from the body 13 of the panel 12 , 14 to which it is attached, as depicted. Alternately the strike surface(s) 28 may be positioned anywhere along one or more of the panels 12 , 14 suitable for providing an accessible surface to receive the head of a mallet, hammer, or other driving device to install the post reinforcement 10 by striking the strike surface 28 to drive the reinforcement 10 downwardly. The strike surface 28 may be integral with its respective panel 12 , 14 , or it may be a separate component attached thereto. Each panel 12 , 14 may have a strike surface 28 that extends along the majority of the top 30 of its respective body 13 . Alternately, one or more panels 12 , 14 may lack a strike surface 28 , and/or the strike surfaces 28 may extend along only a portion of the length of the top 30 of the body 13 of the panel 12 , 14 . Each or all of the strike surfaces 28 may have a surface area of at least about one square inch in one case, or at least about four square inches in another case, to provide a sufficient surface area for striking.
[0019] The post reinforcement 10 may include any of a variety of additional features to facilitate secure attachment to the target post 15 . In one embodiment, one or more of the panels 12 , 14 includes one or more openings 32 in the body 13 thereof. Each opening 32 may be sized and/or configured to receive a fastener 34 therein/therethrough, such as a wood screw, lag screw, etc. to directly secure the post reinforcement 10 to the target post 15 . In one embodiment, panels 12 , 14 positioned opposite to each other across the receptacle 16 (for example, the opposed side panels 14 in the depicted embodiment) may include aligned openings 36 to receive a bolt 38 or other fastener therethrough. To facilitate installation of the bolt 38 , a bore may need to be drilled through the target post 15 at the appropriate location of the post 15 to line up with the openings 36 . In one embodiment, the opening 36 on one side panel 14 may be slightly larger than the opening 36 on the opposite side panel 14 (for example, the opening 36 on one panel 14 can have a ⅜ inch diameter and the opening 36 on the other panel 14 can have a ½ inch diameter) to provide some flexibility in case the bore through the target post 15 is not perfectly aligned with the openings 36 . A nut 40 ( FIG. 1 ) may be used to secure the bolt 38 in place.
[0020] The bodies 13 of one or more of the panels 12 , 14 of the post reinforcement 10 may further include one or more teeth 42 extending inward into/toward the receptacle 16 to penetrate into and grip the target post 15 above ground level. In the depicted embodiment, only the panels 14 include teeth 42 , and the teeth 42 are at different vertical positions relative to each other on their respective panels 14 (see FIG. 3 ). The teeth 42 may be integral with the panels 14 to which they are attached, and they may be positioned/extend generally perpendicular to the body 13 of their respective panel 14 .
[0021] In one embodiment, the post reinforcement 10 includes both the openings 32 / 36 and the teeth 42 on the same ones of panels 12 , 14 . Thus, the tightening of the bolt 38 and/or fastener 34 can serve to drive the teeth 42 into the target post 15 . The teeth 42 may alternately be driven into the target post 15 by other means, including, for example via direct force applied to the panel 12 / 14 with a hammer, mallet, or the like. In the depicted embodiment, the teeth 42 are generally triangular in shape, but the teeth 42 may alternately be formed in any of a variety of shapes, for example jagged/serrated, W-shaped, U-shaped, square-shaped, trapezoidal, or any of a variety of other polygonal or curved forms.
[0022] The post reinforcement 10 may be constructed of any of a variety of materials, and the components thereof may be sized and proportioned according to the particular application, without departing from the scope of this disclosure. In one embodiment, the post reinforcement 10 is formed from a single unitary or integral, seamless sheet of material, for example in one case galvanized steel with a thickness of about ⅜ inch or greater. Accordingly, all of the components that form the basic body of the post reinforcement 10 , including the panels 12 , 14 , the stake portions 18 , the barbs 24 , 26 , the strike surfaces 28 , the teeth 42 , and the like may be shaped by cutting and bending the single sheet of material as appropriate. Alternately, the various components may be formed of a variety of materials including metals, polymers, composites, ceramics, plastics, acrylics, wood, and the like, or combinations thereof, and/or the various components may be separately formed and attached together by any of a variety of methods known in the art, such as welding, riveting, gluing, nailing, and the like, or combinations thereof.
[0023] One exemplary embodiment of the post reinforcement 10 suitable for reinforcing a 4″×4″ wooden post may have dimensions as follows, constructed, for example, from a single sheet of galvanized steel. The reinforcement 10 may have three panels 12 , 14 , each with a body about 6 inches tall and about 3.75 inches wide, set perpendicularly to each other to define the receptacle 16 such as that shown in FIG. 1 . Strike surfaces 28 may extend about ¼ inch outward from each panel 12 , 14 , in a direction perpendicular to the body 13 of the associated panel 12 , 14 and away from the receptacle 16 . Each panel 12 , 14 may include a generally triangular stake portion 18 extending about 6 inches from the bottom 20 thereof and tapering from a width of about 2 inches at the bottom 20 of the panel 12 , 14 to the point 22 . Each stake portion 18 may be centered along the width of its respective panel 12 , 14 . Each stake portion 18 may have its lower tip 22 positioned inward in the direction of the receptacle 16 by about ⅛″ to ¼″ relative to the body 13 of the associated panel 12 , 14 . Each stake portion 18 may include an inwardly-oriented barb 24 and an outwardly-oriented barb 26 , where each barb 24 , 26 is formed from a generally-triangular notch cut into the stake portion 18 and bent inwardly/outwardly (as appropriate) such that the tip of the barb 24 , 26 is positioned about ¼ of an inch from the main body of the respective stake portion 18 . The barbs 24 , 26 may up to between about 1 and 1.5 inches long.
[0024] Each panel 12 , 14 may include openings 32 about ¼ inch in diameter to receive screws therein, which in one embodiment may be about 2 inches long. The opposed panels 14 may also include aligned openings 36 that are sized at about ⅜ inch in diameter on one panel 14 and about ½ inch in diameter on the other panel 14 to receive the bolt 38 therethrough. The side panels 14 may further include teeth 42 that are formed from generally-triangular notches about ¼ inch in length, cut into the bodies 13 of the side panels 14 and bent inwardly such that the teeth 14 extend into the receptacle 16 at about a 90° angle. It should be appreciated that these dimensions are exemplary only, and that a suitable post reinforcement 10 for a 4″×4″ post, or other size post, may alternately take many of a variety of other specific dimensions.
[0025] The post reinforcement 10 may be used as follows, with reference to the non-limiting embodiment set forth above. The user locates a post 15 in need of reinforcement, for example a wooden, wood-based, composite or other type of post at risk of collapse due to rotting wood at or near ground level. The post reinforcement 10 is positioned about the outer perimeter of the target post 15 at ground level, with the points 22 of the stake portions 18 on the ground and the target post 15 received in the receptacle 16 . To position the reinforcement 10 about the target post 15 , it may be necessary to move the stake portions 18 outward against their bias to allow the post reinforcement 10 to fit about the post 15 . A three-sided embodiment of the post reinforcement 10 may enable ease of installation by attaching the reinforcement 10 from the side of the post 15 in an interference/press fit, but a one, two, or four-sided embodiment may alternately be used. In one embodiment, two separate two-sided reinforcements 10 could be used to surround the entire target post 15 without the installment complications inherent to a four-sided design. In this case, however, the barbs 24 , 26 and teeth 42 may need to be adjusted as desired.
[0026] Using a hammer, a mallet, or other appropriate tool, or in some cases stepping with a boot or the like, the user strikes the strike surfaces 28 to drive the reinforcement 10 into the support structure 17 . It may be necessary to use the strike surfaces 28 on more than one of the panels 12 , 14 to facilitate installation. The user continues to drive the reinforcement 10 into the support structure 17 until the stake portions 18 are entirely, or substantially entirely, embedded in the support structure 17 , as shown in FIG. 5 . The bottoms 20 of the panels 12 , 14 may or may be driven into the support structure 17 to some extent. Bottoms 20 also act as a stop surface so the user knows when to stop driving the post reinforcement 10 into the support structure 17 . Due at least in part to the bias of the stake portions 18 , the points 22 thereof may penetrate into the target post 15 at a location beneath the top/ground level of the support structure 17 . The barbs 24 , 26 will thus serve as anchors to resist subsequent removal of the reinforcement 10 by pulling from above.
[0027] With the post reinforcement 10 in position in the support structure 17 , wood screws 34 may be inserted through the openings 32 of the panels 12 , 14 and driven into the target post 15 to secure the reinforcement 10 to the target post 15 above ground level. Further, a hole may be bored through the target post 15 between the openings 36 of the side panels 14 , and a bolt 38 may be passed therethrough and secured with the nut 40 to provide further above-ground securement of the reinforcement 10 . Securing the bolt 38 and/or the wood screws 34 also causes or assists the teeth 42 to penetrate the target post 15 , providing still further support to keep the reinforcement 10 in place.
[0028] In one embodiment, the post reinforcement 10 may further be incorporated into a system including a chemical or substance that inhibits or prevents the rotting of wood. For example, a wood epoxy mixture may be spread on the base of the target post 15 before installation of the post reinforcement 10 . In one embodiment, the interior portions of the post reinforcement 10 may be coated with such a product to facilitate its application to difficult-to-access portions of the target post 15 , for example, to locations at or below ground level.
[0029] Accordingly, the disclosed post reinforcement 10 may extend the usable life of a post 15 that has been weakened at or near ground level, for example as a result of rotting wood, by strengthening the post 15 at the weakened location. Alternately, the post reinforcement 10 can be used at the time of installation of the post 15 and/or prior to showing signs of rot or weakness, as a protective measure.
[0030] Although the invention is shown and described with respect to certain embodiments, it should be clear that modifications will occur to those skilled in the art upon reading and understanding the specification, and the present invention includes all such modifications. | A post reinforcement including a panel having a body portion and a stake portion. The post reinforcement further includes a first barb coupled to and extending away from the panel, wherein the first barb is generally positioned on a first side of the panel. The post reinforcement also includes a second barb coupled to and extending away from the panel, wherein the second barb is generally positioned on a second side of the panel opposite the first side. | 4 |
BACKGROUND OF THE INVENTION
The invention relates to a dilatation catheter having a tube the operative end of which opens into an expandable balloon and a segment of flexible tubing traversing the balloon, sealingly connected to the distal end of the balloon, and capable of being threaded by a guide wire.
Such a dilatation catheter is described in The American Journal of Cardiology, Vol. 49, Apr. 1, 1982, pages 1216 to 1222, and is employed to enlarge constrictions in vessels and body cavities, in particular coronary arteries. At the tip of such a dilatation catheter, an inflatable balloon is disposed, capable of being filled or emptied by way of a lumen inside the catheter.
In the known dilatation catheter, a tube is provided that passes over into a balloon at its anterior end. Through the interior of the balloon and the tube, in the known dilatation catheter, a flexible tube extends, projecting beyond the anterior end of the balloon and sealingly connected to the anterior end of the balloon. Through the inside of the flexible tube, a guide wire is passed, capable of being displaced relative to the balloon during the operation, so that the dilatation catheter can be advanced or retracted along the guide wire. When replacing a dilatation catheter applied with the aid of a guide catheter, it is necessary that the guide wire protrude from the patient's body by a length greater than the length of the dilatation catheter with tube. For this reason, manipulation of the known dilatation catheter is difficult, especially since the forces of friction between the guide wire and the flexible tubing passing all the way through the balloon and the tube are great.
SUMMARY OF THE INVENTION
Departing from this prior art, the object of the invention is to create a dilatation catheter that can be passed easily along a guide wire and simply and easily replaced by another dilatation catheter.
This object is accomplished, according to the invention, in that the proximal end of the balloon is likewise sealingly attached to the length of flexible tubing, and in that the tube opens into the interior of the balloon laterally displaced from the segment of tubing.
Since the segment of tubing coming into contact with the surface of the guide wire is only about as long as the balloon and the tube no longer encloses the guide wire and the guide tubing enclosing it, manipulation of the dilatation catheter is facilitated. Control is improved because of the absence of frictional forces in a long segment of guide tubing. Furthermore, owing to the comparative shortness of the length of tubing, the guide wire need no longer protrude from the patient's body by about the same length as the length of the dilatation catheter.
Suitable embodiments and refinements of the invention are described elsewhere in the present application.
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be illustrated with reference to the embodiment represented in the drawing by way of example. In the drawing,
FIG. 1 shows the anterior portion of the dilatation catheter according to the invention, with tube opening into the balloon,
FIG. 2 shows a cross section of a dilatation catheter in the region of the tube, passing alongside the guide wire, and
FIG. 3 shows a cross section of the dilatation catheter in the region of a gold marker in the balloon.
In FIG. 1, the anterior portion of a dilatation catheter is represented, to be advanced with the aid of a guide catheter not shown in the drawing, having a diameter of some millimeters and a length of about one meter, for example from a patient's right groin throughout the length of the artery to the aorta and the coronary arteries. Through the guide catheter not shown in the drawing, first a guide wire 1 is advanced into the corresponding coronary. A segment of the guide wire 1, which is about 1 m in length, may be seen in FIG. 1. The guide wire 1 serves as instrumentation track to guide the dilatation catheter.
The dilatation catheter has a balloon tube and a tube 3, shown cut away in FIG. 1 and likewise on the order of 1 m in length.
FIG. 2 shows a section of the guide wire 1 and tube 3. The tube 3 serves firstly to transmit thrusts and tensions for pushing the balloon 2 to and fro and rotating it on the guide wire 1. For this reason, it is desirable for the tube 3 to be reinforced by a stabilizing wire 4 in the manner shown in FIGS. 1 to 3. Besides its function of transmitting forces, the tube 3 serves for injection of fluids into the interior 5 of the balloon 2 and for aspiration of fluids when the diameter of the balloon is to be decreased.
As may be seen in FIG. 1, the balloon consists of an envelope 6 and a length of flexible tubing 7, so that the balloon 2 has a passage 8 sealed off from the interior 5 of the balloon. The balloon passage 8 enables the balloon 2 to be thrust onto the guide wire 1 and thereby guided along the guide wire 1.
In FIG. 3, the substantially annular cross section of the balloon 2 is seen, together with the balloon passage 8 through which the guide wire 1 extends. For good transmission of the forces exerted upon the tube 3 to the balloon 2, the stabilizing wire 4 extends into the neighborhood of the distal end 9 of the balloon 2.
As is clearly seen in FIG. 1, at the distal end 9 of the balloon 2 the envelope 6 takes the form of a length of flexible tubing 10, tightly connected to the distal end of the segment of tubing 7. Similarly, the envelope 6 terminates at the proximal end in a segment of tubing 11, sealingly connected firstly to the proximal end of segment 7 and secondly to the tube 3.
The operative end 12 of tube 3, pointing to the right in FIG. 1, terminates in a taper 13 fixed to the tubing 7. Both in the taper 13 and elsewhere at the operative end 12, radial openings 14 are provided in the tube 3, whereby fluid injected into the tube 3 can pass from the tube 3 into the interior 5 of the balloon 2.
In FIGS. 1 and 3, gold stripes 15 and 16 are additionally represented, serving to mark the location of the dilatation catheter in X-ray views.
In FIG. 3, we see a cross section of the balloon 2 in the region of the gold strip 15. The tube 3 with its inner lumen 17 and the segment of tubing 7 with balloon passage 8 are made in one piece in the region shown in FIG. 3, so that the gold stripe 15 assumes a substantially oval form rather than that of a figure-eight.
The guide wire 1 may have a central lumen, not shown in the drawing, for pressure measurement or to contain a contrast medium. To minimize frictional resistance between the interior of the balloon passage 8 and the surface of the guide wire 1, the inside of the tubing segment 7, reinforced by the stabilizing wire 4, and/or the top of the guide wire 1 may be provided with a lubricant coating.
For dilatation of coronary vessels, first the guide wire 1 is introduced through the guide catheter into the proper coronary artery. The guide wire 1 lies freely in the guide catheter and so may be conveniently rotated and controlled. For anatomical orientation, adequate additional doses of contrast medium may be supplied. When the guide wire 1 has passed the constriction in the coronary artery, the tip of the guide wire 1 remains on the far side of the stenosis in the coronary vessel. At this point, and not until, the dilatation catheter according to the invention is thrust onto the guide wire 1 outside the body and advanced through the guide catheter along the track formed by the guide wire 1 into the coronary artery and under the constriction. If the balloon 2 is to be replaced during the operation by a balloon 2 of larger size, it is a simple matter to retract the dilatation catheter according to the invention, leaving the anterior end of the guide wire 1 in the coronary vessel and permitting secure advancement of the replacement balloon with no need to overcome much friction or to relocate the stenosis a second time. If deficient stability of the result of dilatation is suspected, the guide wire 1 may even be left in place for several hours, with a view to renewed dilatation at a later time. The distal end 9 of the dilatation catheter is flattened in the manner described above for better insertability into vascular constrictions.
The invention permits the provision of balloons of various lengths, widths and wall thicknesses to accommodate various pressures, and they may be interchanged with ease. Depending on medical requirements, the dilatation catheters are equipped with tubes 3 of varying weight and flexibility, admitting of differential advance. For larger dilatation catheters, an additional inner lumen, not shown in the drawing, is provided, its anterior end extending to the distal end 9 of the balloon 2 and communicating with the interior of the vessel inside the patient's body. In this way, pressure measurements and injections of contrast medium may be performed. The guide wires 1 of a complete instrumentarium are likewise of different weights and flexibilities. The guide wires 1 have soft, flexible tips, which may be shorter or longer, as well as straight or bowed. If no additional inner lumen is provided in the balloon, a central lumen as above mentioned may be provided in the guide wires for pressure measurements and injections of contrast medium. | A dilatation catheter, in particular for expanding constrictions in coronary vessels, includes a balloon (2) capable of being enlarged by injecting a fluid through a tube (3). The tube (3) is arranged laterally offset from a segment of flexible tubing (7) by which a passage (8) for a guide wire (1) is formed in the balloon (2). | 0 |
PRIORITY CLAIM
This application claims priority from French patent application no. 03/50276, filed Jun. 30, 2003, which is incorporated herein by reference.
BACKGROUND
1. Technical Field
The present invention generally relates to the manufacturing of integrated circuits. More specifically, the present invention relates to a method for oxidizing three-dimensional silicon patterns of very small dimensions.
2. Discussion of the Related Art
“Patterns of very small dimensions” is here used to designate elements in relief having at least one dimension—their width or their length—smaller than 100 nm. Insulated gates of MOS type transistors are considered hereafter as a non-limiting example of such three-dimensional patterns, the gate length being smaller than 100 nm.
FIGS. 1A to 1D illustrate, in simplified partial cross-section view, different steps of a known method for forming a MOS transistor in a P-type doped single-crystal silicon substrate 1 .
As illustrated in FIG. 1A , a thin insulating layer 2 is first formed, after which a polysilicon layer 3 is deposited. Layers 3 and 2 are then successively etched according to a same pattern, to define the insulated gate of the transistor. Gate 2 - 3 is defined to have a length GL of at most 100 nm.
At the next steps, illustrated in FIG. 1B , an insulating layer, generally a multilayer 4 comprising a silicon oxide (SiO 2 ) internal portion 5 and a silicon nitride (Si 3 N 4 ) external portion 6 , is formed. Internal portion 5 generally results from a thermal oxidation of the silicon forming gate electrode 3 , followed by the deposition of a silicon oxide layer. External portion 6 results from the deposition of a silicon nitride layer.
Then, as illustrated in FIG. 1C , multilayer 4 is anisotropically etched to only be left in place on the sides of gate 2 – 3 . First so-called offset spacers 7 are thus formed, which extend gate length GL by a value w. Spacers 7 are then used as a mask upon forming, in substrate 1 , of lightly-doped source/drain regions (LDD) 8 by implantation of N-type dopants. The constraints resulting from the forming of first spacers 7 and their function will be discussed hereafter.
At the next steps, illustrated in FIG. 1D , at least one insulating layer is deposited and anisotropically etched, so that second spacers 10 are formed on either side of gate 2 - 3 . Then, heavily-doped N-type source drain regions 13 (HDD) are formed in LDD regions 8 . In this implantation, spacers 10 are used as masks.
Such a method and the resulting structures have disadvantages linked to offset spacers 7 .
In technologies with a short gate length (GL<100 nm), the first spacers avoid for LDD regions 8 to join in the portion of substrate 1 underlying insulated gate 2 - 3 . This risk is significant due to the fact that the forming of LDD regions 8 of a junction depth of at most 20 nm is delicate.
The forming of first spacers 7 results from a compromise between various constraints. In particular, spacers 7 must have an accurately determined length w/2, smaller than 20 nm, preferably on the order of from 5 to 10 nm. If length w/2 is too short, there is an overlapping between the two LDD regions 8 and the transistor source and drain are short-circuited. Conversely, if length w/2 is too long, length CL of the channel is too long and the transistor exhibits inferior electric performance, especially with a high on-state resistance.
The desired accuracy cannot be obtained with the method of FIGS. 1A to 1C , especially since length w/2 depends on the anisotropic etch methods used ( FIGS. 1B–1C ) to define spacers 7 . These methods are poorly controlled and result in the forming of inhomogeneous spacers. Indeed, on the one hand, it is not known to remove the planar portions of multilayer 4 without etching or overetching its vertical portions intended to form spacers 7 . Such an overetching reduces length w/2 of spacers 7 with respect to the initial thickness of multilayer 4 . Such an overetching is not necessarily symmetrical for a given transistor and, further, when the density of formed transistors is significant, it is inhomogeneous for the different transistors.
The problem described hereabove for transistor gates is more generally encountered as soon as a thin oxide layer is desired to be formed on silicon patterns while the pattern density is very high.
SUMMARY
An aspect of the present invention aims at providing a silicon pattern oxidation method that enables accurate control of the oxide thicknesses formed on the different pattern portions.
An aspect of the present invention aims at providing such a method which enables control of the dimensions of the first spacers of MOS transistor gates of a length smaller than 100 nm.
According to an aspect of the present invention, the present invention provides a method for forming, by thermal oxidation, a silicon oxide layer on an integrated circuit comprising three-dimensional silicon patterns, comprising the steps of:
implanting a first element according to a first angle with respect to the horizontal direction, the first element being electrically neutral and having a first effect on the growth rate of a thermal oxide on silicon; implanting a second element according to a second angle with respect to the horizontal direction, the second element being electrically neutral and having a second effect complementary to the first effect on the growth rate of a thermal oxide on silicon, the second angle being distinct from the first angle, and one of the first and second angles being a right angle; and thermally oxidizing the silicon.
According to an embodiment of the present invention, the first effect is a slow-down effect, the second effect being an acceleration effect.
According to an embodiment of the present invention, the first element is nitrogen and the second element is argon.
According to an embodiment of the present invention, the implantation according to a right angle is performed by placing the integrated circuit in a plasma of the element to be implanted.
According to an embodiment of the present invention, the implantations of the first and second elements are performed by bombarding of the integrated circuit in an implanter.
According to an embodiment of the present invention, the implanted regions of the patterns and of the circuit comprise concentrations of the first and/or second elements smaller than 10 16 at/cm 3 .
According to an embodiment of the present invention, the concentrations of the first and/or second elements range between 5.10 14 and 3.10 15 at/cm 3 .
According to an embodiment of the present invention, the implanted regions of the patterns and of the circuit comprising the first and/or second elements have a depth of at most from 5 to 30 nm.
The present invention also provides a method for forming a MOS transistor in a silicon substrate of a first conductivity type, comprising the steps of:
defining an insulated polysilicon gate on the substrate; performing an oxidation according to any of the preceding embodiments to form a silicon oxide layer thicker on the gate sides than on the planar substrate and gate surfaces; implanting a dopant of the second conductivity type, to form on either side of the gate lightly-doped drain/source regions; forming spacers on the gate sides; and implanting a dopant of the second conductivity type, to form on either side of the gate heavily-doped drain/source regions.
The foregoing aspects, features, and advantages of the present invention will be discussed in detail in the following non-limiting description of specific embodiments in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A to 1D illustrate, in simplified partial cross-section views, different steps of a known MOS transistor manufacturing method; and
FIGS. 2A to 2F illustrate, in simplified partial cross-section views, different steps of a method for forming a MOS transistor according to an embodiment of the present invention.
DETAILED DESCRIPTION
The following discussion is presented to enable a person skilled in the art to make and use the invention. Various modifications to the embodiments will be readily apparent to those skilled in the art, and the generic principles herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
For clarity, same elements have been referred to with same reference numerals and further, as usual in the representation of integrated circuits, the various drawings are not to scale.
FIGS. 2A to 2F illustrate, in partial simplified cross-section views, different steps of a MOS transistor manufacturing method according to an embodiment of the present invention.
As illustrated in FIG. 2A , the method according to an embodiment of the present invention starts with the definition of the transistor's insulated gate comprising a thin insulator 2 and a polysilicon layer 3 on a doped silicon substrate 1 of a first conductivity type, for example, type P.
At the next steps, illustrated in FIG. 2B , an implantation of a first element, according to a first angle with respect to the horizontal direction, is performed.
The first angle is chosen to implant the first element in majority, if not exclusively, in certain given horizontal or vertical portions of the three-dimensional patterns. For example, the first angle is straight. Then, the first element is implanted perpendicularly, that is, only in the planar surfaces of substrate 1 and of gate 3 , with the vertical surfaces, such as the lateral walls of gate 2 - 3 , not being implanted. Regions 41 and 42 are thus formed at the surface of substrate 1 and of gate 2 - 3 , respectively.
The first element is chosen according to the two following criteria. First, it must be electrically neutral, that is, affect neither the insulating character, nor the conductive character, no more than the conductivity type of the material in which it is implanted. Thus, region 41 remains of conductivity type P of substrate 1 in which it is formed. Second, it must have a given effect upon the growth rate of a thermal oxide on a silicon region on which it has been implanted. For example, the first element is nitrogen which has a slow-down effect.
The implantation is carried out so that the nitrogen concentration in regions 41 and 42 is smaller than 10 16 atoms/cm 3 , preferably on the order of from 5.10 14 to 3.10 15 atoms/cm 3 . Further, regions 41 and 42 extend, from the respective upper surface of substrate 1 or of gate 3 , down to a depth of at most from 5 to 30 nm.
At the next steps illustrated in FIG. 2C , an implantation of a second element according to a second angle with respect to the horizontal direction is performed.
The second element is selected on the basis of the two following criteria. First, like the first element, the second element must be electrically neutral. Second, it must have an effect complementary to the effect of the first element in terms of oxide growth. For example, the second element has an effect accelerating the silicon oxide thermal growth. The second element will be xenon or, preferably, argon.
The second angle is selected to be different from the first angle, to implant the second element in majority—if not exclusively—in the portions of the three-dimensional patterns that do not comprise (or comprise it in minority) the first element. For example, the implantation is an oblique implantation intended to implant the argon in majority in the side of gate 2 - 3 . Thus, regions 46 comprising less than 10 16 atoms/cm 3 , preferably from 5.10 14 to 3.10 15 atoms/cm 3 of argon, are formed in the sides of gate 2 - 3 .
At the next step, illustrated in FIG. 2D , the structure of FIG. 2C is placed in an oxidizing and heated atmosphere capable of causing the growth of a silicon oxide layer 50 on the exposed silicon portions. Thus, the growth of the oxide layer is performed in differential and controlled fashion. The thickness of layer 50 varies according to the areas 41 , 42 , and 46 on which it grows in predetermined fashion due to the nitrogen and argon concentrations that they comprise. In the considered example, layer 50 reaches a first thickness T on the sides of gate 2 - 3 and a second thickness H on the planar portions of substrate 1 and of gate electrode 3 , first thickness T being greater than second thickness H. The values of thicknesses T and H are homogeneous for all the gates formed on the substrate. First spacers 55 are thus formed on the sides of gate 2 - 3 , the dimensions of which are controlled.
For clarity, the first and second elements being electrically neutral, regions 41 , 42 , and 46 containing them are no longer shown in FIGS. 2E and 2F .
At the next steps, illustrated in FIG. 2E , a dopant capable of forming, on either side of insulated gate 2 - 3 , lightly-doped drain-source regions LDD 60 , for example of type N, is implanted. As a non-limiting example, it is considered that the difference in the respective oxide growth rates on regions 41 , 42 , and on regions 46 is such that thickness H of the planar portions of layer 50 is sufficiently small, between 1 and 5 nm, for these planar portions to be able to be maintained in place upon the implantation intended for the forming of LDD regions 60 .
Then, as illustrated in FIG. 2F , similarly to what has been described in relation with FIG. 1D , the planar portions of layer 50 are removed. At least one insulating layer, for example, a silicon oxide layer, is deposited and etched to form second spacers 58 on either side of gate 2 - 3 . A dopant capable of forming in substrate 1 heavily-doped (HDD) drain/source regions 62 , for example, of type N, is then implanted.
The method according to this embodiment carries on with standard transistor and/or integrated circuit forming steps in a semiconductor substrate such that, for example, the forming of contacts, metallizations and passivation layers.
This embodiment of the present invention advantageously enables accurate definition of thickness T of first spacers 55 . This enables overcoming the above-described disadvantages.
In particular, this embodiment of the present invention enables accurate definition of thickness T even in the case where a great number of three-dimensional patterns are present at the integrated circuit surface.
Another advantage of this embodiment of the present invention is to enable suppression of the deposition and etch steps linked to the conventional forming of the first spacers.
Of course, embodiments of the present invention are likely to have various alterations, modifications, and improvements which will readily occur to those skilled in the art. In particular, the present invention has been described in the case of a differential oxidation of the sides of an insulated polysilicon gate with respect to a single-crystal silicon surface. However, the present invention applies to the differential oxidation of any three-dimensional silicon pattern. Thus, the pattern may be a trench formed in a single-crystal silicon area. The method according to the described embodiment of the present invention then enables differentiating silicon oxide thicknesses at the bottom and on the walls of the trench. The pattern may also be a polysilicon line, insulated or not, directly formed on a substrate or not.
Further, the embodiments of the present invention have been described in the case of the forming of a silicon oxide layer which is thicker on the lateral walls of patterns than on their planar surfaces. However, it should be dear to those skilled in the art that embodiments of the present invention also apply to cases in which a thicker silicon oxide layer is desired to be formed on the planar surface of patterns than on their lateral walls. An element capable of accelerating an oxide growth is then implanted in majority in the planar surfaces, and an element capable of slowing down the oxide growth is implanted in majority in the vertical walls.
It will also be within the abilities of those skilled in the art to modify the previously-described steps according to a considered technological line. Thus, the orthogonal implantation step of FIG. 2B may be carried out either by a bombarding in an implanter, or by placing substrate 1 in a plasma containing the neutral element in ionized form.
Similarly, it has been previously considered that the planar portions of layer 50 exhibit a thickness H which is sufficiently small to be maintained in place upon forming of LDD regions 60 . It should however be noted that, according to an alternative, these planar portions may be removed before implantation. Thickness H being determined in accurate and homogeneous fashion only by the concentrations of the first and second elements in regions 41 and 42 that do not depend on the density of formed transistors, the removal of the planar portions of layer 50 may be stopped more accurately than in the conventional step of removal of multilayer 4 ( FIG. 1C ), the thickness of which varies when the transistor density is high. Further, given the difference existing between thicknesses T and H, the etching of the planar portions of layer 50 stops before the overetching of thickness T is significant. Moreover, such a removal may then be followed by a new thermal oxidation to form a thin layer intended to protect the silicon surfaces in the subsequent dopant implantation bombarding of LDD regions 60 . According to another alternative, the planar portions of layer 50 are not removed before the forming of spacers 58 , but at a subsequent stage only.
Similarly, it will readily occur to those skilled in the art that the order of the implantations of the first and second elements of FIGS. 2C–D could be inverted. Thus, the vertical walls could be implanted ( FIG. 2C ) before implanting ( FIG. 2B ) the planar surfaces.
Further, the embodiments of the present invention have been described previously in the case of the forming of N-channel transistors. However, the present invention also applies to the forming of P-channel transistors. It is then particularly useful, since the boron diffusion generally used to form the P-type LDD regions diffuses more into an N-type silicon substrate than the phosphorus or arsenic generally used to form the N-type LDD regions 60 of an N-channel transistor. It is then particularly important to be able, according to an embodiment of the present invention, to form first spacers 55 which are sufficiently large to guarantee a non-zero channel length CL and sufficiently small to ensure good electric performances for the resulting transistor.
In the case of CMOS lines in which transistors with the two channel types are formed, the steps of implanting the first and second elements and of oxidizing may be simultaneous. According to an alternative, to take into account the faster diffusion of boron, only the oxidation and the orthogonal implantation, intended to slow down the oxide growth on the planar surfaces, may be performed simultaneously. However, the oblique implantation will be performed separately for the N-channel and P-channel transistors to implant greater doses of the element capable of accelerating the oxide growth in the sides of the P-channel transistor gates.
It should moreover be noted that “substrate” has been used to designate a uniformly-doped silicon wafer as well as epitaxial areas and/or areas specifically doped by implantation-diffusion formed on or in a solid substrate or a substrate-on-insulator (SOI).
Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and the scope of the present invention. Accordingly, the foregoing description is by way of example only and is not intended to be limiting. The present invention is limited only as defined in the following claims and the equivalents thereto.
Electronic components such as transistors that are formed according to the above described methods may be utilized in a variety of different types of integrated circuits, such as memory devices, which may be contained in a variety of different types of electronic systems, such as computer systems. | A method for forming, by thermal oxidation, a silicon oxide layer on an integrated circuit including three-dimensional silicon patterns, includes implanting a first element according to a first angle with respect to a horizontal direction. The first element is electrically neutral and has a first effect on the growth rate of a thermal oxide on silicon. A second element is implanted according to a second angle with respect to the horizontal direction. The second element is electrically neutral and has a second effect complementary to the first effect on the growth rate of a thermal oxide on silicon. The second angle is distinct from the first angle, and one of the first and second angles is a right angled. The silicon is thermally oxidized. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to certain new and useful improvements in fabric sheets used in structural applications and more particularly to an improved warp/knit or warp/stitch reinforced fabric sheet made from a desired number of plies with one or more 0° plies located anywhere in the stack of plies and with localized reinforcement, damage tolerance, and other improved characteristics not found in prior art structural fabric sheets.
2. Brief Description of Related Art
Many structural fabrics are currently made with the warp/knit fabric weaving process. Fabrics of this type are usually comprised of sheets of reinforcing fibers, such as carbon, nylon, glass, etc. and tows, which are later impregnated with a curable matrix, such as many polyesters, phenolics, epoxies, polyimides and the like. Sheets of this type are frequently employed in the manufacture of aircraft parts, as for example, skins of a fuselage and skins of wings. Also these fabrics find a variety of uses in other applications.
There are several inherent limitations in the presently available processes for producing warp/knit fabrics. Typically, the commercially available warp/knit processes are limited to two, three, or four plies and in some cases five plies. There have been certain proposed processes where multi-ply sheets have prepared up to a maximum of eight plies. However, the commercially available processes are typically designed only for two, three, or four plies with four plies being the standard.
In essentially all commercially available processes and apparatus and proposed processes and apparatus which are used for producing a warp/knit or warp/stitch sheet, the 0° ply layer is almost inevitably limited to the upper surface of the sheet. This is due to the fact that the various other plies are applied at stations along a traveling belt with locating pins and held in place under tension on the sides of the belt. The angulated plies such as, for example, a +45° ply, a -45° ply, or a 90° ply, or for that matter other angulated plies, e.g. a 60° ply, are typically held in place and where the fibers are temporarily held in a properly aligned position by means of wrapping fibers forming part of the plies about locating pins on each of the longitudinal sides of a traveling belt. However, in all of the prior art machines, there has not been any effective means for holding the fibers of a 0° ply in place, except on the upper surface thereof. The 0° ply is typically the last ply which is applied from a warp spool, particularly when using a Liba or a Malimo type warp/knit machine or other stitching machine to make the fabric. The space between the 0° ply and the stabilization thread by the warp/knit process is short such that the 0° ply does not have sufficient time to disorient.
Another one of the problems inherent with currently available warp/knit produced fabrics in the production of a quality product is the fact that the fabric is limited to a width capable of being produced by the available warp/knit machines.
The current LIBA warp/knit machines will produce useful fabric up to of 62 inch width. A prior art machine known as the Carl Mayer machine is limited to 60 inch width fabric production with only four layers. The Malimo machine uses a cross over of 90° and 45° plies and this results in somewhat lower strength.
There is no effective means for splicing together individual sheets without resultant thickness variation and lower strength. In the prior art, attempts have been made to splice individual sheet segments together in order to achieve a composite sheet of a selected width. However, it has been found in essentially all cases that there is either substantially reduced strength or increased weight and thickness in the overlap area of the splice.
In addition to the foregoing, there is little or no possibility of allowing for thickness or local damage tolerance in the prior art sheets. In essence, there is no provision on a conventional warp/knit machine to provide areas of increased thickness or local build-up.
The art of warp knitting a fabric is best exemplified by U.S. Pat. No. 4,550,045, dated Oct. 29, 1985 to Harold K. Hutson for Biased (45°) Multi-Layer Structural Fabric Composites Stitched In A Vertical Direction. In the Hutson patent, a warp/knit fabric machine is at least schematically illustrated and shows the application of 90° plies as well as -45° plies and +45° plies and which are vertically stitched together. However, the Hutson patent also exemplifies the limitations in the prior art apparatus and process in that in his preferred embodiment only four plies are provided, which include the +45° ply, the 90° ply, the -45° ply and an overlay of a 0° ply. However, in all cases the overlay is on the upper surface of the plurality of plies, although the Hutson patent also shows that a large number of plies can be applied in a structural fabric. The process of accomplishing this result, even if at all achievable, is inefficient, not practical on a commercial basis and can at least be described as "clumsy".
A stitched fabric with vertical stitching is also taught in German Patent No. 8194 dated Feb. 3, 1949 to Heinrich Mauersberger. This reference disclosed a textile fabric material which is produced by warp knitting. Moreover, in the Mauersberger patent, and also in the aforesaid Hutson patent, vertical stitching is used between the various layers of fibers.
There has also been a process in which a polyester knit thread was used to hold plural facewise disposed plies together. However, this knit thread does little, if anything at all, to improve damage tolerance. Its primary function is to stabilize the warp/knit fabric.
There has been a need for a structural fabric sheet and particularly for an apparatus and a process for producing a structural fabric sheet using a warp/knit machine or a warp/stitching machine in which more than eight plies can be obtained and moreover, there has been a need for a structural fabric sheet of this type in which one or more 0° plies can be located in essentially any desired location on the sheet. Further, there has also been a need for a structural fabric sheet as well as an associated apparatus and method for producing this sheet in which localized damage tolerance can be provided in selected areas and where reinforcement in the sheets can be provided in desired areas and further where doublers and the like can be incorporated in the sheets.
In addition there is a need for a fabric as well as a machine to make such a fabric that controls the modules of elasticity (stiffness) of the fabric in certain directions by use of a hybrid fiber combination, as for example Fiberglass and carbon fiber in specific orientation. Finally, there is need to make very wide fabric for manufacture of very large (wide) parts without splices.
OBJECTS OF THE INVENTION
It is, therefore, one of the primary objects of the present invention to provide a warp/knitted or stitched structural multi-ply fabric sheet which is non-crimped and non-woven and which is capable of being used in structural applications in a highly efficient manner and which can be tailored to meet desired specifications in such selected applications.
It is another object of the present invention to provide a warp/knitted or stitched structural multi-ply fabric sheet in which there are a plurality of plies including one or more 0° plies and where the 0° ply or plies may be located essentially anywhere in the arrangement of plies.
It is yet another object of the present invention to provide a warp/knitted or stitched structural multi-ply fabric sheet utilizing high strength knit thread and with dramatically increased damage tolerance.
It is a further object of the present invention to provide a warp/knitted structural multi-ply fabric sheet in which there may be three or more plies facewise disposed upon one another and made from stacks of plies knitted or stitched together and where some of the plies are angularly arranged with respect to other of the plies.
It is an additional object of the present invention to provide a warp/knitted or stitched structural multi-ply fabric sheet in which fibers of different weight or thicknesses or fibers of different modulus may be included within the sheet.
It is also an object of the present invention to provide a warp/knitted or stitched structural multi-ply fabric sheet which is non-woven and in which stiffener portions may be located in the sheet and which may also include doublers or localized reinforcement for particular applications.
It is another salient object of the present invention to provide a method of producing a thick multi-ply warp/knitted or stitched structural fabric sheet which is non-woven and which can be operated with conventional warp/knitting machines and with modified warp/knitting machines.
It is a salient object of the present invention to provide a process for producing a wide spliced warp/knitted or stitched structural fabric sheet in which several layers of plies are warp/knitted or stitched together in side by side relationship without any substantial loss of mechanical properties at a splice joint.
It is still another object of the present invention to provide both a structural warp/knitted or stitched fabric sheet as well as a method of making the same which is highly effective and which is capable of providing enhanced mechanical properties and freedom of location of local areas of reinforcement.
It is yet another object of the present invention to provide an improved apparatus for producing a warp/knit stitch reinforced structural fabric sheet.
It is still an additional object of the present invention to provide a non-woven, non-crimped fabric with a balanced fiber pattern which eliminates or minimizes warpage when cured.
With the above and other objects in view, our invention resides in the novel features of form, construction, arrangement and combination of parts and components presently described and pointed out in the claims.
SUMMARY OF THE INVENTION
The present invention relates in general terms to a unique warp/knit process as well as warp/knitted structural multi-ply fabric sheets with structural fiber and which fibers are non-woven and non-crimped. These sheets are capable of being used in desired structural applications and capable of being tailored to selected specifications including localized reinforced areas, desired thicknesses, a desired number of plies, desired weight, desired fiber orientation, desired stiffness or strength, and the like.
In one aspect, the warp/knitted or stitched structural multi-ply fabric sheet is comprised of a plurality of angularly arranged plies other than 0° plies, along with 0° plies and which are disposed upon one another in desired angular relationships and where the angular relationships of at least one of these plies may well be different than at least one of the other plies. In addition, a 0° ply is located on a surface of the fabric sheet in a position, if desired, other than on the upper surface.
The term warp/knitted or warp/knitting is used in a broad sense to include the concept of warp stitching since the two are really closely related. Although knitting involves the actual tying of the threads together, certain stitching processes also use two threads as for example, in lock stitching. Thus, as used in the present invention, warp stitching is encompassed by warp knitting and warp knitting is encompassed by the process of warp stitching.
In a more preferred embodiment of this aspect of the invention, the plies may include, for example, a +45° ply, a -45° ply and a 90° ply, as well as a 0° ply. In the prior art, the 0° ply was essentially limited to the upper surface of the stack of plies. However, in the case of the present invention, the 0° ply can be located on the lower surface of the fabric sheet or in between any of the other plies and is not specifically limited to a position on the upper surface of the plies.
In another aspect of the invention, there is a warp/knitted structural multi-ply fabric sheet which is non-woven and which is comprised of at least seven plies facewise disposed upon one another and where certain of the plies are angularly arranged with one another and the angular relationship of certain plies is different than that of certain other plies. There may also be at least one 0° ply in this arrangement of stacked and secured plies. In accordance with the present invention, it is possible to produce a warp/knit multi-axial fabric with no 0° plies, as for example, a +45°, -45°, 90°, -45°, +45° ply arrangement.
It is also possible to produce a balanced fiber pattern ply arrangement in order to eliminate or otherwise minimize warpage in a cured panel. The balanced pattern, when employed, uses parallel outer layers, as for example, where both of the outer layers are +45° plies. Moreover, each of the next groups of plies are parallel. As an example, in a seven ply fabric, the plies could have a pattern of +45°, -45°, 0°, 90°, 0°, -45°, +45°.
Thus, it can be seen that it is possible to apply essentially any number of plies to a stack in order to make a structural fabric sheet. The present invention is not limited to any particular number of plies and is capable of producing multi-ply sheets well in excess of nine ply sheets, which is greater than the maximum number of eight plies in any effectively produced prior art sheet. There have been proposals to make laminated sheets of more than nine plies in the prior art as for example, in the aforesaid Hutson patent. However, these proposals relied upon a single stitching of all sheets together. Thus, while the Hutson patent proposes a 54 ply sheet, it also proposes laying 54 plies upon one another and simultaneously stitching all such plies together in a single operation.
This type of stitching operation with 54 plies is not only impractical due to the difficulty in maintaining the plies in marginal registration, but it requires the capacity of a warp knit fabric machine which is not commercially available. In addition, it requires needle sizes and needle strokes which are capable of stitching 54 individual plies. Consequently, and while in theory, it would be desirable to achieve such a result, the means of achieving the result of a 54 ply sheet in the Hutson patent is not only impractical, it may not even be commercially possible. In accordance with the present invention, however, the number of plies incorporated in any sheet is not necessarily limited by the length of the knit needles.
In the present invention, individual stacks of fiber sheets as for example, seven plies in each individual stack are prepared. Thereafter, two or more of these stacks can be stitched together in individual arrangements. For example, two 7 ply stacks can be stitched together and two other 7 ply stacks can be stitched together to create two stacks each having 14 plies. Thereafter, the stacks of 14 plies can be stitched together. Not only is this a far more efficient operation, it does not necessarily require modification of existing warp knit fabric machines. The number of plies incorporated in any sheet is only limited by the length of the traveling belt, the number of fiber application stations, and the length of the knit needles as well as the lift of the needles sufficiently to clear the final fabric sheet.
In addition to the foregoing, the present invention provides both unique processes and unique apparatus for producing the aforesaid fabric sheets. The invention also provides several unique methods of achieving a 0° ply freedom. In this way, the various plies can be arranged relative to one another and the 0° ply included in any desired orientation within the various other plies and then introduced into a warp/knit machine for ultimate securement of the plies together in a stitching operation.
It is also possible, in accordance with the present invention, to provide areas of doublers or localized reinforcement. In this way, it is possible to provide reinforced sheets having reinforced areas to accommodate particular end use applications.
In addition to the foregoing, it is also possible to vary the thickness and the weight of a ply in order to control the desired percent of a particular fiber orientation. Thus, some plies may be formed of fibers which are thicker or have a denser weight than the fibers used in other of the plies. In addition, it is also possible to use fibers of differing weights and differing thicknesses in a particular individual ply. In this way, it is also possible to account for potential damage tolerance in a structural fabric sheet. A damage tolerance can be achieved by adding to a laminate made from a warp/knit fabric, specialized penetrating Z-axis thread for securing the various fabric plies together.
In each of the aforesaid embodiments, when the plies of the fabric sheets are disposed upon one another, they are then secured together by Z-axis fibers and in effect knitted into a desired multi-ply structural sheet. In this case, the sheet could also be constructed with differing properties such that the sheet may be made with e.g. glass fibers and also with carbon fibers where the carbon fibers provide a higher degree of stiffness reinforcement in certain areas than do the glass fibers.
The stiffness or modulus of elasticity of a fabric may be varied in separate directions with a hybrid mix, as for example all fibers of one type, e.g., fiberglass in one direction and different fibers, e.g. all carbon fibers, in another direction.
The fabric sheets may be ultimately impregnated with a suitable curable resin matrix in order to provide the desired laminate mechanical properties upon curing of the resin matrix. Any of a number of thermoplastic or thermosetting resin materials known in the art may be used for this purpose.
The present invention further provides a process for producing a spliced warp/knitted structural fabric sheet in which there is no significant loss of strength in the areas of splicing of individual sheet segments together. This allows for exceedingly wide sheets to be produced and in fact, allows for production of sheets which can have a width greater than a normal Liba multi-axial warp/knit fabric machine. High performance multi-axial warp/knit fabric made by the Liba equipment is limited to 62 inches, as aforesaid, as a maximum width. In the Malimo machine, maximum width up to 150 inches can be produced. However, fiber arrangements are usually at 88° to 92° with crossovers of 90° fibers, although 90° fibers can be used. This necessarily results in somewhat lower mechanical properties or otherwise quality of material.
One of the desired procedures for producing a very wide fabric is to use side by side conventional Liba warp/knit machines. These machines are constructed so as to provide zero degree plies along with plus and minus 45° plies overlapping the first set of plus and minus 45° plies. These plies are then tied together on the Malimo machine with 88° to 92° fibers which are knitted from side to side such that all plies are secured together in a fixed position, to thereby provide a wide fabric.
Based on the foregoing, it can be seen that a wide number of embodiments of warp/knitted structural multi-ply fabric sheets can be obtained in accordance with the present invention and that the present invention provides several processes capable of producing such multi-ply structural fabric sheets. In addition, apparatus for producing the desired warp/knit structural multi-ply fabric sheets is disclosed. However, only a limited number of the various versions of the multi-ply warp/knitted structural fabric sheet are shown and for that matter only a limited number of the processes and apparatus for producing the same are shown and described herein.
The present invention possesses many other advantages and has other purposes which may be made more clearly apparent from a consideration of the forms in which it may be embodied. As indicated, only a limited number of the embodiments of the structural fabric sheets and the associated apparatus and methods are shown. This limited number of sheets and the apparatus and methods are described in further detail in the following detailed description and illustrated in the accompanying drawings. However, it should be understood that this detailed description and the accompanying drawings are only for purposes of illustrating the general principles of the invention and are therefore not to be taken in a limiting sense.
BRIEF DESCRIPTION OF THE DRAWINGS
Having thus described the invention in general terms, reference will now be made to the accompanying drawings in which:
FIG. 1 is a fragmentary perspective view of a conventional prior art warp/knitting machine for producing a warp/knitted structural fabric;
FIG. 2 is a somewhat schematic plan view showing the arrangement of plies provided by a warp/knit fabric machine for producing one form of a structural fabric sheet in accordance with the present invention;
FIG. 3 is a series of three schematic views comprised of:
FIG. 3A which show a plurality of steps in one embodiment of the process of the present invention for producing a structural fabric sheet in which a pair of 0° plies are located at the outer surfaces of a stack of plies forming the sheets;
FIG. 3B which shows the production of a structural fabric sheet in which 0° plies are located in the middle of the stack of plies and +45° plies at the outer surfaces of the sheets;
FIG. 3C shows the production of a structural fabric sheet in which 0° plies are located next to but under the outer +45° plies of the stack;
FIG. 4 is a fragmentary perspective view showing one form of apparatus in accordance with the present invention for producing, for example, an eleven ply warp/knit fabric with 0° ply location freedom;
FIG. 5 is a somewhat schematic view showing, for example, an eleven ply multi-axial fabric sheet having five intermediate 0° ply layers;
FIG. 6 is also a somewhat schematic prospective view showing a slightly modified form of machine for producing a warp/knit fabric in accordance with the present invention;
FIG. 7 is a schematic view showing the steps involved in producing a fourteen ply fabric sheet in accordance with the present invention;
FIG. 8 is a schematic view showing the steps involved in a modified method of producing a fourteen ply fabric sheet in accordance with the present invention;
FIG. 9 is a perspective view partially broken away and showing doublers provided for local raised edge reinforcement in a multi-ply variable step thickness structural fabric preform in accordance with the present invention;
FIG. 10 is a schematic view showing the relationship of plies for purposes of splicing together warp/knit fabric sheets;
FIG. 11 is a schematic view showing the arrangement of the plies of FIG. 10 in a spliced warp/knit fabric sheet; and
FIG. 12 comprises a series of (three) views showing several methods used to produce a structural sheet with a varied amount of drapability that include:
FIG. 12A which shows a minimum drape in a sheet;
FIG. 12B which shows a somewhat greater but still slight drape in a fabric sheet; and
FIG. 12C which shows a much greater drape in a fabric sheet.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now in more detail and by reference characters to the drawings, a prior art warp/knitting machine P will now be described for purposes of understanding the prior art and its relationship to the present invention.
A. Prior Art Warp/Knitting Fabric Machine
The prior art warp/knitting fabric machine P included an endless belt 20 trained about rollers 22, and one of which was driven for moving the belt in a continuous and endless path. Upstanding pins 23 at the two side edges of the continuous belt 20 were provided for wrapping the structural fibers about these pins at the edges of the belt 20 and to hold structural fibers at a desired angle.
The upper surface of the belt was designed to receives tows of fiber from a first reciprocatively movable fiber feed member at a first station 24 for applying +45° parallel fibers, as a first ply, to the endless belt 20. A second station 26 was arranged to supply fibers, as a second ply, in a 90° parallel orientation by means of a reciprocatively shiftable feed member. Finally, a third station 28 was provided with a reciprocative feed member designed to apply parallel fibers at a -45° angle on top of the 90° angle fibers in order to form a third ply. Thus, a first ply of +45°, a second ply of 90° and a third ply of -45° was then provided.
In each of the aforesaid stations 24, 26 and 28, spools of fiber 30 were provided for feeding strands of the fiber to the reciprocative members which then applies the individual strands to the belt.
A warp beam 32 was also provided as part of the apparatus P for providing 0° tow fibers 34, as best shown in FIG. 1. In this case, the tow fibers were applied to the upper surface of the -45° fibers as shown in FIG. 1. Thereafter, a knitting station 36 was provided for knitting the four plies together in the form of a fabric sheet which was then rolled up about a take-up roller 38. As indicated previously, another prior art apparatus for producing warp/knit fabric is disclosed in the Hutson U.S. Pat. No. 4,550,045. In like manner, as also indicated previously, a method for producing chain stitched fabrics was shown in Germany Patent No. 8194 dated Feb. 3, 1949 by Heinrich Mauersberger.
As further indicated previously, the prior art apparatus was limited to essentially four plies. In a few cases, sheets of a greater number, of up to eight plies, were produced with this type of warp/knit machine, but in all cases had only one upper surface of 0° fibers. However, the machine had to be modified in order to produce a sheet of more than four plies. No one has previously effectively made a warp/knit structural fabric sheet with more than eight plies and no one has made an effective structural fabric sheet in which there was complete 0° ply freedom location. Furthermore, no one has incorporated high strength sewing or knitting threads to achieve damage tolerance in the end product.
B. Fabric Sheets Of The Invention With 0° Ply Location Freedom and Unlimited Number of Plies.
FIG. 2 is somewhat of a schematic illustration showing the arrangement of plies in a sheet which can be produced in accordance with the present invention. In this case, a sheet schematically designated as 40 is provided with a plurality of 90° fibers constituting a first ply 42, and which received a ply of +45° fibers 44 and followed by a third ply of -45° fibers 46, as shown. In addition, a fourth ply 48 of 0° fibers is also shown. However, it should be understood that these 0° fibers can be located anywhere in the arrangement of the plies, as hereinafter described. The 0° ply can also be supplied using a large number of individual spools of fiber tow in place of a warp beam. This type of fiber pattern arrangement was not readily possible in accordance with the prior art warp/knit machines.
In the prior art apparatus, the edge of the continuous belt 20 was provided with the pins 23. Thus, as the tows moved back and forth across the belt during continuous belt movement in order to make a ply, the fibers of the tow wrapped around the pins on each side of the belt and the tension on the fibers wrapping about the pins 23 at the longitudinal edges of the belt 20 held the fibers in an aligned position. The knit threads applied at the knitting station 36 typically had a spacing of five rows per inch of width and a stitch step usually from about 1/8 inch to about 1/4 inch. These knit threads formed chain-stitches or so-called "back and forth zig-zag stitches", known as "tricot" stitches. Thus a straight line chain-stitch or tricot zig-zag stitch or a combination of both of them could be used to combine the several layers in a knitting or sewing operation.
The sheet produced in accordance with this prior art apparatus using, for example, polyester 70d thread had a minimum effect on mechanical properties of the laminated fabric sheet and essentially had little or no damage tolerance properties and had similar properties to laminates made from unidirectional unstitched or unknit materials with the same thickness and fiber pattern.
In accordance with the present invention, it is now possible to make for example an eight ply fabric, a sixteen ply fabric, or a twenty four ply fabric sheet, etc. or sheets of intermediate number of plies. There is essentially no known upper limit to the number of plies which can be applied to a structural fabric sheet. In most cases, a desired fiber pattern, at least for four of the plies, is 0°, +45°, 90° and -45° although +30° to +60° plies in place of the 45° is sometimes preferred. Also, 0°, +60°, -60°, 0° is an example of a preferred fiber orientation pattern for certain structural application. In accordance with the present invention, the fiber plies are often arranged with respect to one another at acute angles in multiples of 15°. However, even here the plies are not limited to this precise arrangement and they could be applied at other acute angles with respect to one another. A few variations of the processes used for producing sheets with one or more 0° plies in locations other than on only the upper surface, are hereafter described.
Referring now to FIG. 3, there is schematically illustrated three different warp/knit arrangements to produce multi-ply/multi-axial structural sheets and include FIGS. 3A, FIG. 3B and FIG. 3C. In FIG. 3A, there is shown an arrangement in which there is a first group of four plies comprising 0°, +45°, 90° and -45°. A second group of four plies comprises 0°, -45°, 90° and +45°. The second stack is inverted so that the 0° ply becomes a lower ply. It should be recognized that when inverted the -45° ply becomes a +45° ply and the +45° ply becomes a -45° ply. These two stacks of four plies as show in FIG. 3A are then stitched together, as shown in Step 3 of FIG. 3A to form a sheet having a ply arrangement of 0°, +45°, 90°, -45°, -45°, 90°, +45° and 0°. In each case, it can be seen that the plies are facewise disposed upon each other in each of the individual stacks. Further, they are knitted together with a tricot knit polyester 70d thread or similar thread and with a 2.5 to about a 12 gauge pattern. This can be varied depending on the desired handling characteristics (drapability) and mechanical properties of the fabric.
FIG. 3B shows an arrangements in which there are the same two stacks of fiber plies and with the first stack being formed in a Step 1 having a 0°, +45°, 90° and a -45° plies. In Step 2 a four ply stack is formed with a fiber ply arrangement of 0°, -45°, 90° and +45°. The first stack produced in accordance with Step 1 is then turned over and the two stacks of Step 1 and Step 2 are then sewn together in order to form the product shown as +45°, 90°, -45°, 0°, 0°, -45°, 90° and +45°; in Step 3B.
FIG. 3C also illustrates a further embodiment of producing an eight ply sheet in which the -0° plies are located just under and just over the two +45° surface plies, such as +45°, 0°, -45°, 90°, 90°, -45°, 0°, +45° shown in FIG. 3C, Step 3.
In accordance with the above, it can be seen that the 0° plies can be essentially located in any desired location in the stack of plies. The few exemplary illustrations of an eight ply sheet construction in FIG. 3 show various arrangements in which the 0° plies can be located and secured using a 2.5-to a 12 gauge tricot knit on the outer surface. Moreover, the 0° plies are located immediately under the outer surfaces of the sheet as shown in the arrangement of FIG. 3. This group of figures also shows that the 0° plies could be located at the center of the sheet or otherwise at other locations in the sheet. In all cases, the various plies produced in the third step (Step 3 of FIG. 3) are also stitched together with a polyester or similar thread, as for example, a 70d light weight thread or the like as employed in FIG. 3A. A 12 gauge to a 2.5 gauge chain-knit or tricot knit is used to secure the two stacks of fabric sheets into a single unitary sheet and which is shown in the three steps in FIG. 3A, 3B and 3C. Increasing the knit gauge from 2.5/inches to a gauge of 5 or greater produces a more stable fabric and a stiffer handling dry fabric. It also reduces the drape of the fabric to be used in the manufacture of double contour parts.
It has been found in accordance with the present invention that it is possible to produce multi-ply fabric sheets including a large number of plies e.g., nine or more plies, due to the fact that the various plies can be at least temporarily secured to one another during the actual warp/knit process. Thus, in one approach, the various plies of fabric are contacted at selected locations with a slight amount of a curable resin. The amount of resin employed is quite small, usually 2% to 6% by weight of fiber, and is only sufficient to merely hold the individual fibers and plies in a parallel array. The quantity of resin in an epoxy composite finish is often sufficient for this task. It is important in the sheets of the present invention to assure a uniformity and parallelity of each of the fibers in an individual ply. Moreover, it is important to ensure that all of the plies are held in proper registration with respect to one another. This can be readily accomplished by using the small amount of resin contacted onto the individual plies and onto the individual fibers in a particular ply. If desired, the resin may be advanced to a B-stage but is not hardened at this point in time. The fabric may be placed through heater rolls to soften the resin and then through chill rolls to compact and set the resin to thereby hold the fibers in the desired arrangement.
Another approach used in connection with the holding of the 0° plies in a proper registration and the holding of the fibers in a particular ply in parallel arrangement is to use the knitting stitching approach, as for example, chain stitching or tricot stitching, as aforesaid. In either case, the fibers are held in parallel arrangement in a ply and the various plies are properly aligned relative to one another.
In the chain stitching, loops are formed under each of the fibers and in somewhat of a zig-zag arrangement. The stitches are locked together on their underside along with a bobbin thread that cause the individual vertical threads to be locked into place. In the tricot stitching arrangement, rows of side-by-side needles are used to form loops with a zig-zag arrangement with respect to the fibers. In this way, the various plies and particularly the 0° plies are pre-stabilized. Thus, before the 0° plies are even applied to the other plies, they are typically pre-stabilized by the knitting or the small amount of resin, as aforesaid.
In accordance with the present invention, it is also possible to produce a sixteen ply fabric by repeating Step 1 of the previous process in order to accomplish two stacks or four plies from Step 1. Step 2 would also be repeated in order to form two stacks of Step 2. Thereafter, the four stacks would be combined together in order to provide a sixteen ply warp knit fabric. Again, the various stacks could also be reoriented in any desired arrangement before securing together in the same manner as described in connection with an eight ply sheet. The same process can be used for producing a twenty four ply fabric sheet or a thirty two ply fabric sheet, etc. always holding the balanced plies in a desired overall pattern.
Some of the fibers which may be used in the formation of the sheets of the invention are those formed of "glass, Kevlar, graphite (carbon), polyester and Nylon". The threads which are used in the stitching are preferably natural threads or otherwise synthetic threads. Among the preferred threads are glass, Kevlar, graphite (carbon), polyester and Nylon and which are selected in accordance with the desired properties.
C. Warp/Knit Fabric Machine of the Present Invention
FIG. 4 illustrates one form of warp/knit machine in accordance with the present invention for producing a structural multi-axial, multi-ply fabric sheet in one continuous operation and which can include one or more 0° plies located in positions other than the upper surface or for that matter, only on the upper surface, as may be desired. In the embodiment of the invention as shown in FIG. 4, there is provided a continuous belt 52 which also has upstanding retaining pins 53 along the longitudinal edges of the belt.
The apparatus of the invention further comprises a first station 54 for applying a ply of +45° fibers. A second station 56 provides a second ply of 0° stabilizes fibers. A third station 58 provides 90° fibers. Again, the stations 54 and 58, as well as other subsequently described fiber application stations, except for the 0° ply stations, will each include a carriage which shifts back and forth across the belt as the belt is rotating and thereby applies the fibers in the desired angulated path. The carriages at each of these stations will similarly contain sources of fiber tow or threads for application to the continuous belt. Moreover, the carriages will move in the desired angulated relationship. Thus, for example, the carriage at the first station may move in approximately a +45° path with respect to the path of movement of the belt. The carriage at the third station which applies 90° fibers will move back and forth across the belt. The carriage at a fifth station, as hereinafter described, will move back and forth across the belt at a -45° angle with respect to the path of movement of the belt. Finally, it should be noted that the +45°, 90° and -45° carriages are not exactly at these angles as they apply fibers to pins on each side of a traveling belt. The exact angles of these carriages are adjusted to the speed of the belt so that the resulting parallel layers of fibers are at the required angle.
A fourth station 60 also provides an additional ply of stabilized 0° fibers over the 90° ply. A fifth station 62 a ply of -45° fibers followed by a sixth station 64, which is another 0° stabilized ply station, and which applies a sixth ply of 0° stabilized fibers. This is also followed by a seventh station 66 applying -45° fiber plies and an eight 0° stabilized station 68 applying an eighth ply of 0° stabilized fibers. A ninth station 70 applies a 9th ply of 90° fibers and a tenth station 72 applies a 10th ply of 0° stabilized fibers. Finally, in the embodiment as shown in FIG. 4, there is an eleventh station 74 which also provides an 11th ply of +45° fibers.
Thus, in accordance with the apparatus of FIG. 4, the stations apply plies to obtain a sheet schematically shown in FIG. 5, such that:
the 1st station applies a +45° ply;
the 2nd station applies a 0° ply;
the 3rd station applies a 90° ply;
the 4th station applies a 0° ply;
the 5th station applies a -45° ply;
the 6th station applies a 0° ply;
the 7th station applies a -45° ply;
the 8th station applies a 0° ply;
the 9th station applies a 90° ply;
the 10th station applies a 0° ply; and
the 11th station applies a +45° ply.
Each of the various eleven plies which will form the fabric sheet of FIG. 5 are then knitted together at a station 76 comprised of a plurality of aligned and vertically penetrating knitting or sewing needles and which tie the fiber plies together by knitting or stitches to stabilize and form the sheet. The sheet is then wound on a take-up roller 78, all as best shown in FIG. 4.
It should be understood that the embodiment as shown in FIG. 4 is only illustrative of numerous embodiments which could be provided. For example, only two or three, or for that matter, more 0° stations could be provided. In addition, the other stations could provide additional or other angular fiber arrangements. Nevertheless, this embodiment of the apparatus shows that it is possible to now provide a large number of plies on a warp/knit machine and with 0° plies located anywhere throughout the sheet as may be desired.
Due to the fact that there are a large number of individual spools of fiber used to produce the single 0° plies of material, it is often times more practical to use a 0° beam of parallel rows of 0° fibers or 0° tow which is prepared prior to the actual start of the warp/knit operation. Thus, in the embodiment as shown in FIG. 4, the five beams used at the stations 56, 60, 64, 68 and 72 all must be prepared so that the fibers are stabilized. This will ensure that all of the fibers remain in their desired 0° orientation in parallel arrangement with one another without forming gaps or overlaps as they pass along the traveling belt to the knitting station.
FIG. 6 shows an apparatus used for stabilizing the 0° fabric which is to be used in a multi-ply sheet produced in accordance with the present invention. In this case, the fiber is unwound from individual spools 80 which constitute a spool storage and displacement station. Moreover, at this station, tension control may be maintained on the individual fibers 82 as they are unwound from the spools 80. In addition, a roll arrangement 84 is provided to maintain individual tow tension control. The various fibers under tension are then passed through alignment pins 86. It can be seen in FIG. 6 that alignment pins are located on both the upper and lower surfaces of the individual tows.
Three tow-spread rolls 88 are also provided to ensure that the tows are evenly and individually spread in parallel arrangement. Thereafter, the tows may be knitted together with a tricot stitch at a knitting station 90 having a plurality of knitting needles, as shown, and which thereby produces a stabilized 0° ply of fabric 92. The fabric ply may be then rolled on a beam 94 to form a layer of 0° stabilized tow.
It is also possible to use 0° layers of carbon or other fiber tow directly from creels. Moreover, it is possible to mix the fibers forming part of the various plies so that one ply may contain e.g. glass fibers of 0° orientation of one inch width and the remainder of the ply may contain e.g. carbon fibers of the same 0° orientation. In this exchange, the various plies may contain alternate bands of differing widths, as for example, a band of glass fibers of 0° orientation with e.g. a one inch width and alternate two inch width bands of carbon fibers and of a 0° orientation. It is also possible to use alternate fiber tows of, for example, fiberglass and carbon, or any other mix, to make the ply for the fabric.
As indicated previously, it is possible to mix the various fibers in the individual plies. Thus, one ply may contain for example fiberglass and another ply may contain carbon fibers. Moreover, additional plies may contain still further fibers such as for example Kevlar fibers. Thus, a hybrid mix of fibers may be in a ply, or alternate ply layers of fiber may be in the fabric.
Each of the fibers in the 0° layers may be fixed by including a small number of 90° thermoplastic coated fine fiberglass threads across the fabric. A thermosetting coating could be, for example, an epoxy "sticky" coating and the thread could again be a fine fiberglass thread. The thread is preferably applied in a line transversely across the 0° fibers or otherwise in a continuous process along with the warp/knit processing using a technique of back and forth application. Thereafter, the thread would be impressed into the 0° fiber tows by compaction rollers for stabilization of the 0° fibers.
One stabilized process for achieving a 0° fiber ply in a desired location would be to warp/knit at least two or more individual subassemblies and then warp/knit the subassemblies together. The concept of producing individual stacks and then warp knitting the stacks together has been partially shown in FIG. 3. However, it is also possible to warp knit a large number of stacks together in order to form a wide warp knit fabric.
FIG. 7 shows one approach for a production of a thick warp/knit fabric. As an example, and in a first step, a stack containing a ply of 0°, +45° and -45° plies is produced. A second stack of 0°, -45° and +45° plies is produced in a second step. The stack produced in the second step is turned over and the stacks produced in steps 1 and 2 are thereupon knitted together with the addition of a 90° ply in a third step in order to form a seven ply stack with 0° plies on the outer layers. Thereafter, or otherwise, simultaneously, in a fourth step, a stack of 0°, +45° and -45° plies is produced. In addition, and in a fifth step, a stack of 0°, -45° and +45° plies is produced. This stack in accordance with step 5 is also turned over and the stacks of step 4 and step 5 are then knitted together, also with the addition of a 90° ply to make a seven ply product in a step 6.
As a final step in the production of the thick fabric containing fourteen plies, the two fabrics of steps 3 and 6 are then knitted together in order to form the thick fabric as shown in step 7.
FIG. 8 shows the production of another modified form of producing a thick fabric. In this case, in step 1, a four ply fabric is shown produced in a warp/knit process. In step 2, a three ply warp knit fabric is produced and then turned over. In third and fourth steps, a four ply stack and a three ply stack are respectively produced. The stacks of steps 2 and 4 are thereupon turned over and the four stacks are warp knitted together in order to produce a fourteen ply fabric. It can be seen in connection with the production of these fabrics, whether they are regular fabrics or thick fabrics, that there is a freedom of location of 0° plies. These 0° plies can be essentially located anywhere in the stack as desired.
In connection with the freedom of location of the 0° plies, it is possible to form a first ply in accordance with Step 1 and a second ply in accordance with Step 2 as shown in FIG. 8. Thereafter, the sub-sheet of Step 1 would then be turned over so that the 0° ply is adjacent to the 0° ply of the sub-sheet formed in Step 2. In this way, a sheet having a ply arrangement of: +45°, 90°, -45°, 0°, 0°, -45°, 90°, +45° would be formed. Further, other combinations could also be formed. In addition, it is not necessary to use four plies and three, four, five or more plies could also be used in order to locate the 0° plies in any desired position in the sheet.
It is to be noted in accordance with the present invention that when a sheet is to be prepared with a large number of plies, all such plies are not sewn directly together. Rather, individual stacks of plies are formed. Thus, two or three or more of stacks may be formed and which are subsequently stitched together. Furthermore, not all of the stacks are marginally registered and stitched together in one operation. As an example, two or more stacks may be stitched together and in a second operation two or more additional stacks may be stitched together and in a third operation two or more additional stacks may again be stitched together, etc. These individual stacks may then be stitched to one another in order to form the multi-layer fabric. This approach to making a sheet with a large number of plies has been found to be quite efficient and capable of being accomplished on commercially available warp knit machines.
D. Variation in Fiber Thicknesses and/or Weight
It is also possible to vary the thickness and for that matter, the weight, of each ply in order to control the fiber orientation percent and the resultant laminate structural properties. The few following examples are illustrative to show the various possibilities of controlling thickness and weight in a ply or among a plurality of plies.
If it were desired to obtain a (0°, +45°, 90°, -45°)n pattern with 25% 0°, 50% +/-45°, and 25% 90°, then fiber tows would be used in the following amounts:
______________________________________ 0° = 145 g/m+45° = 145 g/m 90° = 145 g/m-45° = 145 g/m 580 g/m.sup.2______________________________________
145 grams per square meter is a typical weight for a layer of 3K (3,000 filament tow) carbon fibers. However, it is possible to make a fabric with less weight per ply, although the resultant material will have lower mechanical properties or be far more expensive if made from a carbon fiber tow. It is also possible to spread lesser weight tows on the plies. It is further possible to provide plies with greater weight than the 145 grams per square meter per ply. For example, each ply of material could be 200 gm/m 2 with the 4 plies of material weighing 800 gm/m 2 . This pattern would cure to a thicker panel but would still have the same mechanical properties of the fibers in a 0°, +/-45° and 90° orientation.
If it were desired to obtain a (0°, +45°, 90°, -45°) pattern with the same overall weight but with a fiber pattern of 50% 0°, 25% +/-45° and 25% 90°, then fiber tows would be used in the following amounts:
______________________________________ 0° = 290 g/m.sup.2+45° = 73 g/m 90° = 145 g/m-45° = 73 g/m 580 g/m.sup.2______________________________________
If it were desired to obtain a (0°, +45°, 90°, -45°) pattern with the same overall weight but with a fiber weight percent pattern of a 40% 0° ply, 40% +/-45° ply and 20% 90° ply, then fiber tows would be used in the following amounts:
______________________________________ 0° = 232 g/m+45° = 115 g/m 90° = 116 g/m-45° = 116 g/m 580 g/m.sup.2______________________________________
In the three above-identified examples of varying the fiber ply weight, the percent of change of fiber orientation will alter the mechanical properties of the laminate substantially. Nevertheless, by varying the individual fiber areal weight of a ply, it is possible to maintain the same total fabric weight with the same number of plies and maintain a constant laminate thickness. Additional control over the fiber pattern and the resultant mechanical properties can also be obtained by increasing the number of plies in a stack forming a structural sheet or by varying the overall weight of the fibers in a stack.
E. Damage Tolerance
It is also possible to account for damage tolerance and to reinforce a warp/knit fabric by substituting different types of penetrating knit thread. For example, a Kevlar 29 thread of 1600 d or other similar strength thread could be used in place of a 70d polyester thread in the final knit assembly.
The following four examples show how a damage tolerance can be built into a warp/knit fabric sheet which is impregnated with resin and cured. Each of these two examples are set forth with respect to a flat panel sheet.
______________________________________Unstitched - (0°, +45°, 90°, -45°).sub.3S(Approximately 0.32")Compression - Un-notched 75,000 psiCompression After 23,000 psi70 Ft. lbs. Impact-1/2"diameter steel ballPeel - G.sub.1C <1 in. lb./in.Stitched - 1600 d Kevlar - 40 penetration/in..sup.2(0°, +45°, 90°, -45°).sub.3S (Approximately0.32)Compression - un-notched 65,000 psiCompression After 40,000 psi70 Ft. lbs. Impact-1/2"diameter steel ballPeel - G.sub.1C Flexural Failure at >36 in. lbs./in.Stitched - 1600 d Kevlar - 40 penetration/in..sup.2(0°, +45°, 90°, -45°).sub.S (Approximately0.11")Compression - Un-notched 80,000 psiCompression Open Hole 52,000 psiCompression After Impact- 42,000 psi1/2" diameter steelball (26 Ft. lbs.)Stitched - (400 d Kevlar - 40 penetration/in..sup.2(0°, +45°, 90°, -45°).sub.S (Approximately0.10")Compression - Un-notched 90,000 psiCompression Open Hole 58,000 psiCompression After Impact- 40,000 psi1/2" diameter steelball (26 Ft. lbs.)______________________________________
Mode of Failure
No Stitching-De-lamination
Stitched-No De-lamination
When considering the above four examples of stitched and unstitched flat panels, the unstitched flat panel will fail by de-lamination under compression or compression after impact loading. The stitched panel will fail by compression shear with no de-lamination. The unstitched panel has the highest strength undamaged, but has the lowest damage tolerance. The thick panel with the 1600 d Kevlar stitch thread had the lowest undamaged strength and among the best damage tolerance properties. The thin panel with Kevlar 29 1600 s stitch thread had lower undamaged strength and surprising maximum damage tolerant properties. The thin panel with Kevlar 29 stitch threat had high undamaged strength properties along with good damage tolerance properties. Thus the choice of a stitch thread affects mechanical properties.
It is also possible to provide localized reinforcement in a warp/knit fabric by producing a sheet which can vary in the number of plies over the length or width of the sheet. For example, FIG. 9 is a partial fragmentary perspective view of a sheet having a local reinforcement by a different number of plies over the area of the sheet. Thus, in FIG. 9 there is a sheet 100 comprised of an overall four ply stack or segment 102. A portion of the sheet is provided with another stack to make a five ply stack or segment 104 and another portion of the sheet is provided with two additional stacks to make a six ply stack or segment 106.
In addition utilizing a skin which can vary in the number of stacks, as for example, a four ply stack to a five ply stack to a six ply stack as shown in FIG. 9, it is possible to add doublers to these stacks. For example, a first doubler 108 formed of a two ply stack is added to and surrounds the periphery of the four ply stack as shown in FIG. 9. A second continuous doubler 110 is added to the five ply stack in the sheet 100 and surrounds the peripheral edge portion of this five ply stack, thereby forming a total of seven stacks on the edge periphery of the stack or segment 104. A third two stack doubler 112 is added to the periphery of the third stack containing six plies and thereby forms an eight stack outer periphery on the six ply stack 106.
In the aforesaid example of adding local reinforcement and doublers, the four ply sheet segment 102 may have a thickness of 0.216 inches, the five ply sheet segment 104 may have a thickness of 0.270 inches and the six sheet segment 106 may have a thickness of 0.324 inches. With the doublers added, the first sheet segment 102 with the doubler added would have a thickness of 0.324 inches and the second sheet segment 104 with the doubler 110 added would have a thickness of 0.378 inches and the third sheet segment 106 with the added doubler 112 would have a thickness of 0.421 inches. In the previously described sheet 100, it can be seen that this stack is a balanced seven ply warp/knit fabric sheet with a fiber pattern of repeat +45°, -45°, 0°, 90°, 0°, -45° and +45° stacks. The material is warp/knit with 70d polyester thread to form four individual multi-ply stacks. A leader and a tail are attached to the stacks in order to lead these stacks properly into the warp/knit machine. One sheet segment 104 and the second sheet segment 106 will be cut and placed over the full length four ply sheet segment 102. Thereafter, a two stack picture frame type doubler is cut and laid over and placed on the sub-sheets 102, 104 and 106. The doubler may be held in place by using a portable tuft gun or hand stapler or a heat set with pressure to lightly secure the stacks in their aligned positions, eventually with a slight amount of curable resin.
This assembly, as shown in FIG. 9, is then introduced into the warp/knit machine initially starting with the leader attached to the four ply sheet section 102. For this purpose, a Kevlar 29 knit thread of 1600 d may be used in place of the polyester knit fibers to increase damage tolerance. This assembly of plies is then passed through the warp/knit machine with, for example, a five gauge stitch thread (five rows per inch) with a 1/8 inch stitch or knit step to secure all of the sheets segments and the doublers together. This thereby forms a stable warp/knit pre-form which is then ready for stitching additional stiffness or is otherwise ready for final resin matrix impregnation or so-called "resin film infusion" (RFI) or "resin transfer molding (RTM) processing.
F. Wide Spliced Fabric Sheet
The present invention also provides a unique spliced wide fabric sheet and method for producing a spliced wide fabric sheet. In the prior art, attempts to splice two fabric sheets together in order to increase the overall width thereof typically and almost always resulted in weakness along the spliced joints or excess thickness and weight caused by the overlap area of the joint. As a result, there was always a reluctance to splice two or more sheets together because of the inherent loss of strength along the splice joints. In addition, there would always be an extra thickness of fabric at an overlap spliced joint that has a major effect on the tooling design and cost.
In accordance with the present invention, it is possible to splice two or more sheets together without any substantial loss of mechanical properties at the splice joint. In order to accomplish the splicing, two warp/knit fabric machines may be used. In the example attendant to FIGS. 10 and 11 of the drawings, a 50 inch warp/knit machine and a 141 inch warp/knit machine were used in order to produce a 139 inch useful width fabric sheet with seven plies. Moreover, the plies used in the fabric sheet had a fiber pattern of +45°, -45°, 0°, 90°, 0°, -45°, +45°. Furthermore, in the example attendant to FIGS. 10 and 11, the sheet had two splices in each of the +45° and -45° plies and no splices in the 0° or 90° plies.
Referring again to FIG. 10, it can be seen that there is a first sheet sub-panel P-1 comprised of three warp/knitted plies having a fiber pattern of +45°, -45° and 0°. Each of these plies are 50 inches wide using a five gauge tricot knit pattern and a 70d polyester thread. However, it is also possible to use a knit of 2.5 to 12 gauge in order to produce this first sub-panel P-1. As a second step, three additional plies were used to make a 50 inch wide sub-panel P-2 in FIG. 10 and this 50 inch wide sub-panel P-2 had a fiber pattern of -45°, +45° and 0°. Moreover, the same gauge of knitting was used as in the first sub-panel P-1 and the same polyester thread was also employed.
In addition, a second set of plies were added together in order to form a like sub-panel P-1 so that there were two sub-panels P-1. Further, a second sub-panel P-2 is also formed such that there are a pair of sub-panels P-2 as shown in FIG. 10. It can be seen that each of the sub-panels P-1 and P-2 have an overall width of 50 inches.
As a third step in the production of the spliced sheet, a third sub-panel P-1' and another third sub-panel P-2' are also formed. Again, a similar pattern for the sub-panel P-1' of +45°, -45° and 0° is employed. Initially, this sub-panel P-1, has a width of 50 inches with 45° plies and with only a 48 inch wide 0° ply, leaving a one inch band on each of the opposite edges of this sub-sheet which is the area used to make an overlap in the joint.
As a fourth step, the sub-panel P-2' is formed much in the same manner as a sub-panel P-1 with a fiber pattern of -45°, +45° and 0°. Here again, the sub-panel P-2', is 50 inches wide with 45° plies and a 48 inch 0° leaving a one inch band of 45° plies on each edge of the fabric which again constitutes the area of overlap in a splice joint.
It can be seen that in the first and second steps of producing the sub-panels P-1 and P-2, the panels thus produced are all 50 inches wide in all three plies. However, in Steps 3 and 4 one third of the fabric is warp/knit with 0° plies only 48 inches wide thereby leaving a one inch wide band of 45° fibers along each edge of the fabric.
As a fifth step in the production of the spliced fabric segments, two lengths of sub-panels P-1, as shown in FIG. 10, are combined with one length of the sub-panel P-1' as now shown in FIG. 10. Two lengths of the sub-panel P-2 are combined with one length of the sub-panel P-2' with only one ply (a 90° ply) centered between the sub-panels P-1 and P-2. These two panel segments along with a full width 90° center ply between the two segments are then knitted together using, for example, a 2.5 to a 12 gauge 70d polyester thread or similar thread. It is also important in this example to note that one of the 50 inch wide fabric panels is required to be slit to 42 inches of width so that the final product will fit into an existing warp/knit machine. (A 150 inch wide warp/knit machine if available would not require this extra step.)
In the splice zone, +45° and -45° plies overlap one another by one inch and there are no more than two overlapping plies in any area of the seven ply product sheet which is being produced. The P-1 and the P-2 sub-panels are fed into the warp/knit machine such that the splice zones created are offset by one inch. In this way, there are no more than two plies overlapping in any area of the seven ply sheet which is being produced. Thereafter, the completed warp/knit fabric may be trimmed to a width of 139 inches as shown in FIG. 10.
G. Hybrid Warp/Fail Fabric
It is also possible to make various hybrid fiber preforms, as for example, using differing fiber mixtures, as may be desired. For example, regular 33 million psi modulus carbon fibers at +45° and -45° and 90° orientations and high 42 million psi or higher modulus carbon fibers at 0° may be warp/knit to produce a fabric with higher stiffness in the 0° than in the +/-45° or 90° orientation. Fiberglass combinations can also be employed to control stiffness in one direction or to lower overall cost. It is also possible to make a sheet which is relatively soft and bendable with one material in a first direction and with a rigid material in an alternate direction. Thus, a sheet could be bendable in a 0° direction and rigid in a 90° direction. This can be accomplished by laying nylon or fiberglass tow in the 0° first or soft direction and carbon fibers in the 90° direction. Again, any variation thereof can also be achieved. A product using carbon fibers in all +45° and -45° orientations can be made to obtain increased torque or twist resistance strength and fiberglass in the 0° and 90° directions for lower modulus or for lower cost.
It is also possible to incorporate alternate widths of high strength fiber, such as carbon fibers e.g. 2 inches wide, and fiberglass tow e.g. 1/2 inch wide, to make a fabric sheet of lower cost but with strength almost equal to a sheet formed of all carbon fiber. This will also provide added damage tolerance strength under tensile loading from bands of fiberglass strips running lengthwise across the width of the panel.
H. Drapability
FIG. 12 schematically shows various ways in which to obtain a desired degree of drapability in a fabric sheet. A multi-axial warp/knit fabric can be manufactured by the processes as described herein and which is very stable. However, the sheets heretofore described are difficult to form into double contour shapes. There has been a need for a sheet material which can be doubled contoured in order to form a desired shape with good handling characteristics and yet also make high quality flat parts.
FIG. 12A shows a fabric warp/knit using a ten gauge straight chain knit thread that produces minimum drapability and maximum stability. It can be seen that needles 160 apply stitching to the fibers 162.
FIG. 12B shows a lighter gauge chain knit fabric produced with a 5 or a 2.5 gauge straight chain knit thread. In this case, because of the lighter tie thread count, drapability is improved. Further, less stitching is employed and this adds to the drapability of the fabric which is produced with the needles 160 and the stitching fibers 162.
FIG. 12C shows an all tricot knit fabric 164 with further increased drapability. In this case, the stitch gauge is reduced to 2.5 rows per inch and the stitch forward step is increased from one-eighth inch to one-fourth inch or even greater until the fabric becomes actually too fragile to handle. Fabric made with a one knit path through the warp knit machine and with minimum knit thread density produces materials with a maximum drapability.
The sheets of the present invention can be used to make warp/knit fabric which can be cut, stacked and stitched to make a dry fiber preforms with full freedom of fiber stacking alignment and individual ply fiber areal weight which can be used in structural aircraft and aerospace components, aqueous components and other environments where high strength and reduced weight are desired. Further, the invention allows the use of glass and other lower cost fibers in order to make multi-layered products for application in the sports industry, building trades, transportation industry, etc.
The present invention allows the formation of a complete dry fiber preform with built in damage tolerance directly from a warp/knit machine. Further, the invention has splicing methods to make a special wide fabric with no substantial loss of mechanical properties across the entire length of the splice. In addition, the invention allows for complete freedom of location of 0° fibers in a multi-ply sheet. Layers of different, but yet controllable, fiber plies may also be included in the same sheet. In addition, the fiber areal weight and thickness per ply can be varied as well as the overall fiber orientation. As indicated, damage tolerance properties can be added to the sheet and doublers and localized area build-ups can also be used direct at a warp/knit station.
Thus, there has been illustrated and described unique and novel multi-ply structural fabric sheets and unique methods and apparatus for producing the same and which achieve all of the objects and advantages which have been sought. It should be understood that many changes, modifications, variations and other uses and applications will become apparent to those skilled in the art after considering this specification and the accompanying drawings. Therefore, any and all such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention. | An improved warp/knit stitch reinforced multi-axial non-crimp layered fabric sheet used in structural applications, as for example, in aircraft and water applications, e.g. the skin of an airplane wing or fuselage structure, in water applications, e.g. skins of surfboards and boats, and in other areas where high strength and relatively light weight is required. The fabric is comprised of a plurality of plies facewise disposed upon one another and knitted or stitched to form a structural sheet. Each fabric ply is made of strands of aligned structural fibers which can be later impregnated and even pre-impregnated with a resin curable matrix. The improved sheet is formed by applying unidirectional non-crimp and non-woven plies of different angular relationship to one another, e.g. a +45°, a 90° and a -45° ply and locating 0° plies in essentially any position in the ply arrangement such that the 0° ply can be on the bottom of the sheet, on top of the sheet, or interposed between plural ply layers of the sheet. The sheets are then knitted or stitched together to make a stack of multi-axial fabric layers. The fiber weight and thickness can also be varied throughout the sheets by using plies of different thicknesses or differing weights of fibers. Moreover, the percentage of a certain type of fiber in a particular ply can be varied. In addition, damage tolerance can be built into the cured laminate. Further, doublers and local area reinforcements can also be included in the sheet. In addition, a warp/knit, or warp/stitched fabric may be made to a desired width without otherwise affecting the structural properties of the sheet. An apparatus and a method for producing the fabric sheets is also disclosed. | 8 |
TECHNICAL FIELD
The present invention relates generally to wearing apparel, and relates more specifically to apparel, such as exercise clothing and the like, which can be locked to a stationary object to secure the clothing against theft.
BACKGROUND OF THE INVENTION
Runners and other exercisers often encounter a problem when they wear a warm-up suit during the initial phases of exercise, in that once the wearer begins to exert himself or the ambient temperature warms up, the warm-up suit is no longer needed. The exerciser is now faced with the problem of what to do with the warm-up suit while he continues his workout, since many exercise areas, especially running tracks, lack proper facilities for locking up personal belongings. Yet leaving the warm-up suit unattended and unsecured is an invitation to theft. This problem is especially aggravating in the case of a runner, for example, whose continued exercise will take him to geographically remote locations. Since sportswear and exercise apparel can sometimes cost several hundreds of dollars, there is a need to provide a means for safely and temporarily storing the exercise apparel at a workout site when it is not needed.
Department stores and the like have long used cable locking devices to secure expensive clothing to their respective fixtures. These devices are typically passed through a sleeve or other area of the garment and locked to a rack. While such arrangements are satisfactory in retail surroundings where store clerks are present, these prior art locking devices do not provide total security in an unattended environment. Given sufficient time, a would-be thief could rip the seam of the garment, remove the garment from the fixture, and make off with a serviceable garment.
Thus, there is a need for an improved arrangement for locking a garment to a stationary object to secure the garment against theft.
There is a further need for a garment which can be secured to a stationary object so completely that removal of the garment from the stationary fixture would necessitate its virtual destruction, thereby rendering the garment unserviceable and removing the incentive for theft.
There is yet another need for a locking arrangement for securing a garment to a fixture such that the garment cannot be removed from the locking device by simply slitting the seams of the garment.
There is still another need for an improved arrangement for locking a garment to a stationary object which does not require extraneous locking devices.
SUMMARY OF THE INVENTION
As will be seen, the present advantage overcomes these and other disadvantages associated with prior art garment locking arrangements. Stated generally, the present invention comprises an improved arrangement for locking a garment, such as a warm-up suit or the like, to a stationary object to secure the garment against theft. The arrangement fastens the garment to a fixture so securely that unauthorized removal of the garment from the fixture would require the virtual destruction of the garment, thereby rendering the garment unserviceable and removing the incentive for theft. The arrangement of the present invention secures the locking device in such a way that the garment cannot be removed from the locking device by merely slitting the seams of the garment. In one aspect, the present invention comprises a locking arrangement which is integral with the garment so as not to require a separate locking device.
Stated somewhat more specifically, a first embodiment of the present invention comprises a garment having an eyelet operatively associated with a major portion of the garment. An elongated locking device is passed through the eyelet and secured to a stationary object. In the disclosed embodiment, the eyelet is located in a major portion of the garment removed from the seams, such that the garment cannot be removed from the locking device by slitting the seams.
A second aspect of the present invention comprises a garment and a length of cable attached to a major portion of the garment along a substantial portion of the length of cable. In the disclosed embodiment, the cable is fastened into the seams of the garment. Two free ends of the cable are normally disposed within a pocket, for example. The free cable ends are locked to a stationary object to secure the garment against theft.
Thus, it is an object of the present invention to provide an improved arrangement for locking a garment to secure the garment against theft.
It is a further object of the present invention to provide a garment which can be secured to a stationary object so completely that removal of the garment from the stationary object would necessitate its virtual destruction, thereby rendering the garment unserviceable and removing the incentive for theft.
It is yet a further object of the present invention to provide a locking arrangement for securing a garment to a fixture wherein the locking device is secured in such a manner that the garment cannot be removed from the locking device by slitting the seams of the garment.
It is still another object of the present invention to provide an improved arrangement for locking a garment to a stationary object which is fully self-contained and does not require extraneous locking devices.
Other objects, features, and advantages of the present invention will become apparent upon reading the following specifications, when taken in conjunction with the drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of an upper body garment having eyelets according to the present invention.
FIG. 2 is a rear view of the upper body garment of FIG. 1.
FIG. 3 is a front view of the upper body garment of FIG. 1 being folded a first time.
FIG. 4 is a front view of the upper body garment of FIG. 3 folded a second time.
FIG. 5 is a front view of the garment of FIG. 1 folded and locked to a fixed object.
FIG. 6 is a front view of a lower body garment according to the present invention.
FIG. 7 is a front view of an upper body garment according to a second embodiment of the present invention.
FIG. 8 is a front view of a lower body garment according to a second embodiment of the present invention.
FIG. 9 is a detailed view of a first end of a cable locking device which forms a part of the garment of FIG. 8.
FIG. 10 is a detailed view of a second end of the cable locking device of FIG. 9.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, in which like numerals indicate like elements throughout the several views, FIG. 1 discloses an upper body garment 10 according to the present invention. The upper body garment 10 comprises a main body 11, a collar 12, a waistband 13, sleeves 14 and 15 extending from the garment body, and cuffs 16 and 17. A zipper 18 runs down the front center of the garment 10 and divides the front portion of the garment into left and right panels 19 and 20, respectively. The rear portion of the garment main body 11 is comprised of a single panel 21, as shown in FIG. 2.
Eight eyelets 22-29 are located on the upper body garment 10. The eyelet 22 is located in the front right panel 20 of the garment and the eyelet 23 is located on the corresponding front left panel 19. The eyelets 24 and 25 are located in the center area of the rear panel 21; the eyelet 24 is located on the left side of the rear panel and the eyelet 25 on the right side. There are two eyelets on each sleeve 14, 15. The right sleeve 14 has the eyelet 26 located on the front portion and the eyelet 27 on the rear portion. The eyelets 28 and 29 on the left sleeve 15 are located similarly.
The eyelets are preferably made of a flexible, high strength plastic material that will not irritate the skin. The eyelets may optionally be covered with a flap of material when not in use.
A cable locking device 40 is shown in FIG. 4. The device 40 is made up of a length of cable 41 and locking ends 42 and 43. The cable 41 and at least one of the locking ends 42, 43 are dimensioned to be received through the eyelets 22-29. The cable described in the present invention may be comprised of plastic, metal, or any other material having the requisite strength and toughness properties that would make it difficult to cut. The plastic exterior of the cable helps the cable to run smoothly along the garment fabric and also helps prevent the cable from rusting.
To lock the upper body garment 10, the garment is placed flat with the front panels 19 and 20 lying on top the rear panel 21 as shown in FIG. 1. In this position all front eyelets 22, 23, 26, and 28 align with all the rear eyelets 24, 25, 27, and 29. Next, the garment is folded in half so as to superimpose the left sleeve 15 onto the right sleeve 14 as depicted by the arrow 44 shown in FIG. 3. Again the eyelets on the right half of the garment align with those on the left. The garment is then folded a second time along an axis located halfway between the sleeve eyelets and the eyelets located on the main body 11 of the garment 10, as shown by the arrow 45 in FIG. 4.
With the garment completely folded and all of the eyelets thus aligned, one end 42 of the cable 41 is passed through all of the eyelets. The cable 41 is then passed around a fixed object 46 as shown in FIG. 5. The garment 10 is secured to the fixed object 46 by locking the cable ends 42 and 43 together.
While the use of the garment 10 has been described with respect to a cable 41 which is passed through the various eyelets, it will be appreciated that other elongated locking devices such as chain and lock, or a padlock within elongated hasp may be used in lieu of the cable 41.
In the first embodiment of the present invention, each eyelet 22-29 is attached to the garment 10 at a location removed from any fabric edges or seams. In addition each eyelet 22-29 is located at a position on the garment so that all eyelets will align when the garment 10 is folded. For example, the right front eyelet 22 is located a distance halfway between the right side edge 30 and the zipper 18. The left front eyelet 23 is similarly positioned. Moreover, the eyelets 24-25 located on the rear panel are located one-quarter of the width of the garment 10 in from the respective side edges. The eyelets located on the sleeves are positioned an equal distance from the eyelets on the main body 11 of the garment 10. In this manner, when the garment has been folded in the manner hereinbefore described, all of the eyelets will be aligned, thereby facilitating the passing of the cable through the various eyelets.
Turning now to FIG. 6, the lower body garment 50 has eyelets located in the hip and ankle areas. Furthermore, the upper front left and right hip eyelets 51 and 52, respectively, are positioned one-fourth of the width from the left and right side seams 55 and 56, respectively.
The lower body garment 50 is folded and locked in the same manner as described above for the upper body garment 10. First, the lower body garment 50 is placed flat so that the front eyelets 51-54 align with the eyelets located on the rear portion of the lower body garment (not shown). The lower body garment 50 is then folded in half along a vertical line, which causes the left eyelets to align with the right eyelets. Finally, the lower body garment is folded in half again along a horizontal line, joining the eyelets located in the hip area with those located in the lower leg area. With all of the eyelets thus aligned, the lower body garment 50 is ready to be locked in the same manner as that previously discussed for the upper body garment 10.
While the present invention has been disclosed with respect to garments having a plurality of eyelets which align when the garment is folded in a particular manner, it will be understood that a greater or lesser number of eyelets may be used, and that eyelets may be located so as to align when the garment is folded in a manner different from the manner described hereinabove.
Turning now to a second embodiment of the present invention, FIG. 7 shows an upper body garment 60 having a length of cable 61 sewn onto the inner face of the garment. Within the upper body garment 60, the cable 61 begins at a first pocket 63 and travels along one side 64 of the garment up to the shoulder 65 and neck 66 areas of the garment, around to the other side 67 of the garment and back down into the opposite pocket 68. A substantial length of the cable 61 is sewn on the garment 60 and attached along its length. The length of cable 61 has lockable mating elements 69 and 70 secured to its ends. The lockable mating elements 69 and 70 are normally located in opposite pockets 63 and 68, respectively.
FIG. 8 shows a pair of trousers or other similar lower body garment 75 having a length of cable 77 sewn into the lining of the garment. The cable 77 is sewn along the seam 79 of the outer part of a first leg, up across the hip area 80 and down the seam 81 of a second leg. To incorporate a locking mechanism at intermediate points along the length of the cable 77, junctions 82 and 83 are provided near a first and second pocket 84 and 85 respectively. Lockable elements 86 and 87 are attached to junctions 82 and 83 normally located in the first and second pockets 84 and 85, respectively. The assembly of the cable 77, junctions 82 and 83, and lockable mating elements 86 and 87 is shown in more detail in FIGS. 9 and 10.
The garments 60, 75 are secured to a stationary object by extracting the free ends of the cables 61, 77 from their normal storage positions inside their respective pockets. The free ends are then passed around a stationary object and locked together to secure the garments against theft.
The cables 61, 77 are preferably made of a flexible material so that it can be easily sewn into the garment and easily move with the garment. Moreover, it is preferable that the cables be flexible so that they cannot be easily ripped away or cut from the garment. The cables 61, 77 are also preferably flat in cross section so as to eliminate unsightly bulges in the lines of the garment and not cause discomfort to the wearer. The cables 61, 77 of the disclosed embodiment are comprised of high strength plastic or a metal coated with plastic. The plastic inhibits rust formation and splintering of the metal cable which may cause damage to the surrounding fabric.
The cables 61, 77 must be properly secured to the garment. This can be accomplished by providing a strip of plastic extending laterally from the cable. The strip of plastic would be sewn into the seam of the garment. Alternatively, a flat cable having apertures along the length of the cable may also be used. Apertures may be provided along the length of the cable 61 or 77 through which a needle may pass to stitch the cable into the seam of the garment.
The length of cable required for the second embodiment of the invention may vary with the size and design of the garment. The upper body garment 60 of FIG. 7 would require approximately 70 inches of continuous cable for a men's large size. The lower body garment 75 of FIG. 8 would approximately require approximately nine feet of continuous cable for a men's extra-large size.
The lengths of cable 61, 77 described in garments 60 and 75 may be comprised of one cable having two free ends or two separate cables, one end of each cable being lockable to a corresponding end of the other cable. In addition, while the length of cable described in both aspects of the present invention has lockable mating elements attached to the free ends of the cable, it is anticipated that equally effective results may be obtained if eyelets were attached to the free ends of the cables and a separate locking device were passed through the eyelets and locked to secure the cable ends together.
Finally, it will be understood that the foregoing embodiments of lockable clothing have been disclosed by way of example, and that other modifications may occur to those skilled in the art without departing form the scope of the appended claims. | The present invention relates to an improved locking arrangement for clothing. In one aspect of the invention, a garment includes an eyelet operatively associated with a major portion of the garment. An elongated locking device, such as a lockable cable, is passed through the eyelet to secure the garment to a stationary object. In a second embodiment of the invention, a garment includes a length of cable attached to a major portion of the garment along a substantial length of the cable. The cable has a free end operatively associated with a device for locking the cable to a stationary object to secure the garment against theft. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation application of U.S. patent application Ser. No. 11/247,791, filed Oct. 11, 2005, now U.S. Pat. No. 7,516,941 entitled VALVE WITH ACTUATION SUB-ASSEMBLY, by Applicant Eric Nathaniel Combs, which is herein incorporated by reference in its entirety.
TECHNICAL FIELD AND BACKGROUND OF THE INVENTION
The present invention generally relates to a valve and, more particularly, to a ball valve for use in the fire fighting industry.
Valves, specifically ball valves, within the fire fighting industry have gone through relatively little change over the years except with regard to actuation method. Initially, valves were manually operated through push/pull rods attached to the valve handle in order to open and close the valve. However, over time, handwheel gear drive actuation, electric actuation, rack and sector actuation and slow close actuation have been developed to provide flexibility and expanded capability of the valve applications. Because the actuation device for each method is significantly different, revised valve bodies were developed to accommodate attachment of the different actuation devices to the valve. While a small portion of the exterior of the valve was changed, the basic water way of the valve was not altered. The result is a single valve requirement, 2.5″ ball valve for instance, will have as many as four different body configurations to provide the user with the opportunity to select from the five different actuation methods.
Consequently, a valve manufacturer is required to have a large inventory of valves to accommodate the various different body configurations. Furthermore, a different mold is required for each valve, which increases the cost to produce the different style valves. In addition, once the valve is installed because the valve bodies are not interchangeable, the valve actuation methods cannot be changed after installation. Furthermore, repair parts for the respective valves tend to be more expensive due to the lack of commonality of the valve bodies.
Accordingly, there is a need for an improved valve that can accommodate different actuation devices without the need for different valve bodies.
SUMMARY OF THE INVENTION
According to the present invention, a valve body is provided that can be used in combination with any one of a plurality of actuation sub-assemblies that allow the user to fully open, fully close, or partially open the valve, including, for example, a mechanical actuation sub-assembly, a gear actuation sub-assembly, including an electric gear actuation sub-assembly or a handwheel gear actuation sub-assembly, a slow-close actuation assembly, a rack and sector actuation sub-assembly, or the like, or provide for only a fully open valve or fully closed valve, such as a pneumatic or hydraulic actuation sub-assembly.
Consequently, the present invention has reduced the inventory requirements of a valve manufacturer and, further, provides a valve that can be retrofit with another actuation sub-assembly even when installed.
In one form of the invention, a valve assembly includes a valve body, with an inlet, an outlet, and a chamber extending between the inlet and the outlet, a valve ball, an actuator, and an actuation sub-assembly. The valve ball includes a ball body and a transverse passage extending through the ball body. The valve ball is positioned in the chamber and is positionable between a valve open position wherein the transverse passage of the valve ball provides fluid communication between the inlet and the outlet and a valve closed position wherein the ball body blocks the fluid communication between the inlet and the outlet. The valve ball also includes an engagement surface for engagement by the actuator. In addition, the valve body includes a valve body wall with a planar portion. The planar portion includes a mounting surface for mounting the actuation sub-assembly to the valve body, with the actuator extending through the planar portion of the valve body wall for engagement with the engagement surface of the valve ball and for engagement by the actuation sub-assembly.
In one aspect, actuation sub-assembly comprises a manual actuation sub-assembly, a twist-lock actuation sub-assembly, a gear actuation sub-assembly, such as an electric gear actuation sub-assembly or a handwheel gear actuation sub-assembly, a rack and sector actuation sub-assembly, a slow close actuation sub-assembly, or a pneumatic or hydraulic actuation sub-assembly. Further, the actuation sub-assembly may include the actuator.
In other aspects, the valve body wall includes a cylindrical portion, the cylindrical portion having terminal edges termination at opposed sides of the planar portion. In addition, the valve body further includes a pair of valve seats, with the cylindrical portion extending between the pair of valve seats and the planar portion extending between the valve seats and spanning between the terminal edges of the cylindrical portion.
According to another form of the invention, a valve body includes a valve body wall having a cylindrical portion and a planar portion and first and second valve seats, with the generally cylindrical portion extending between the first and second valve seats. A valve ball is positioned between the valve seats in the chamber formed by the valve body wall. The valve ball has a ball body and a transverse passage extending through the ball body and is positionable between a valve open position wherein the transverse passage provides fluid communication between the inlet and the outlet and a valve closed position wherein the ball body blocks fluid communication between the inlet and the outlet. In addition, the valve ball includes an engagement surface for engagement by an actuator. The planar portion of the valve body wall defines a mounting surface and has a transverse passageway extending therethrough for receiving the actuator cooperative with one of each of a manual actuation sub-assembly, a gear actuation sub-assembly, such as an electric gear actuation sub-assembly or a handwheel gear actuation sub-assembly, a twist-lock actuation sub-assembly, a rack and sector actuation sub-assembly, and a slow close actuation sub-assembly.
In one aspect, the planar portion extends between the first and second valve seats.
In other aspects, the valve body wall includes second and third planar portions interconnecting the first planar portion and the cylindrical portion. The second and third planar portions also extend and span between the valve seats.
Accordingly, the present invention provides a valve body that can be used in a number of valve configurations, including a mechanically actuated valve configuration, an electrically actuated valve configuration, a handwheel actuated valve configuration, a slow-close valve configuration, a rack and sector actuated valve configuration, or a pneumatically or hydraulically actuated configuration, or the like.
These and other objects, advantages, purposes, and features of the invention will become more apparent from the study of the following description taken in conjunction with the drawings.
DETAILED DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic drawing of a valve body of the present invention with examples of different actuator sub-assemblies that may be mounted to the valve body;
FIG. 1A is an exploded perspective view of the valve body of FIG. 1 ;
FIG. 2 is a perspective view of a valve body with a manual actuation sub-assembly;
FIG. 3 is an elevation view of the valve body and actuation sub-assembly of FIG. 2 ;
FIG. 4 is a cross-section view taken along line IV-IV of FIG. 3 ;
FIG. 5 is an elevation view of the manual actuation sub-assembly;
FIG. 5A is an exploded perspective view of the sub-assembly of FIG. 5 ;
FIG. 6 is a cross-section view taken along line FIG. VI-VI of FIG. 5 ;
FIG. 7 is a perspective view of the valve body of the present invention with a slow-close actuation sub-assembly;
FIG. 8 is an elevation view of the valve assembly of FIG. 7 ;
FIG. 9 is cross-section view taken along line IX-IX of FIG. 8 ;
FIG. 10 is a cross-section view taken along line X-X of FIG. 8 ;
FIG. 11 is a side elevation view of the slow-close actuation device of the slow-close actuation assembly;
FIG. 12 is a top plan view of the slow-close device of FIG. 11 ;
FIG. 13 is a bottom plan view of the slow-close device of FIG. 11 ;
FIG. 14A is a cross-section view taken along line XIVA-XIVA of FIG. 11 ;
FIG. 14B is a cross-section view taken along line XIVB-XIVB of FIG. 12 ;
FIG. 15 is a perspective view of the valve body of the present invention with a gear actuator sub-assembly;
FIG. 16 is an elevation view of the valve assembly of FIG. 15 ;
FIG. 17 is a cross-section view taken along XVII-XVII of FIG. 16 ;
FIG. 18 is a cross-section view taken along line XVIII-XVIII of FIG. 16 ;
FIG. 19 is a side view of the gear actuator sub-assembly;
FIG. 19A is an exploded perspective view of the gear actuator sub-assembly of FIG. 19 ;
FIG. 20 is a cross-section view taken along line XX-XX of FIG. 19 ;
FIG. 21 is a cross-section view taken along line XXI-XXI of FIG. 19 ;
FIG. 22 is a side elevation view of the valve body of the present invention incorporating a twist lock actuator sub-assembly;
FIG. 23 is a cross-section view taken along line XXIII-XXIII of FIG. 22 ;
FIG. 24 is a side elevation view of the twist lock actuator sub-assembly of FIG. 22 ;
FIG. 25 is a cross-section view taken along line XXV-XXV of FIG. 24 ;
FIG. 26 is an exploded perspective view of the twist lock actuator of FIG. 24 ;
FIG. 27 is an enlarged side elevation view of a rack and sector actuator sub-assembly;
FIG. 28 is a perspective view of the rack and sector actuator sub-assembly;
FIG. 29 is a top plan view of the rack and sector actuator sub-assembly of FIG. 27 ;
FIG. 30 is a cross-section view taken along line XXX-XXX of FIG. 27 ; and
FIG. 31 is an exploded perspective view of the rack and sector actuator sub-assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 , the numeral 10 generally designates a valve body of the present invention. As will be more fully described below, valve body 10 is configured to receive one of several actuation sub-assemblies for opening and closing the valve. For example, valve body 10 is configured to receive an actuator of a manual actuation sub-assembly, a gear actuation sub-assembly (which can be either electrically driven or driven by a handwheel), a twist lock actuation sub-assembly, a rack and sector actuation sub-assembly, or a slow-close actuation sub-assembly. Alternately, valve body 10 may incorporate the actuator, with the actuation sub-assemblies adapted to cooperate with the actuator and the valve body. Though for ease of description, the actuation sub-assemblies described herein incorporate the actuator. Further, though illustrated and described in reference to a ball valve, it should be understood that the concepts of the present invention may be used with other types of valves, such as gate valves or butterfly valves or the like.
Referring to FIG. 1A , valve body 10 includes a housing 12 and a valve ball 14 . Housing 12 includes a housing wall 16 and a pair of mounting flanges 18 and 20 for mounting the valve body between a respective pair of flanges in a piping system, for example. Valve ball 14 is located in passageway 22 of housing 12 and, further, captured therein by a pair of valve seats 24 and 26 , which form a pair of opposed valve seat sealing surfaces 24 a , 26 a ( FIG. 4 ) for valve body 10 . As would be understood by those skilled in the art, valve ball 14 includes a transverse passageway 28 , which when aligned along the longitudinal axis 12 a of housing 12 is in fluid communication with the inlet 30 and outlet 32 of valve seats 24 and 26 . To close the valve, valve ball 14 is pivoted or swiveled about its vertical axis 14 a on a pivot bolt 34 by an actuator, which will be more fully described below, so that its valve ball wall 36 is seated in the valve seats 24 and 26 to thereby close the fluid communication between the inlet and outlet of the valve.
Referring again to FIG. 1A , as noted above, housing 12 includes a housing wall 16 . To accommodate the various actuators, housing wall 16 includes a generally cylindrical portion 16 a and a generally planar portion 16 b , which is offset from the circumference of cylindrical portion 16 a by an offset portion 40 and forms an adapter plate 38 . Offset portion 40 is generally planar and perpendicular to planar portion 16 b and, further, like planar portion 16 b , extends between flanges 18 and 20 . Plate 38 provides a generally planar 42 mounting surface for the respective actuation assemblies described herein and includes a transverse opening 44 through which the actuator of the respective actuation assembly extends for engagement with valve ball 14 .
In each of the respective actuation assemblies described herein, the actuators that engage the valve ball are substantially identical so that each of the various actuation assemblies may be substituted for another actuation assembly even after the valve has been installed. Further, a single valve body may be used as a manually actuated valve, a twist lock actuated valve, a gear drive actuated valve, a rack and sector actuated valve, and a slow-close actuated valve. This modular aspect provides several advantages. For example, common tooling may be used in the manufacturing of the valve bodies and, further, in some of the actuator assembly parts. As would be understood, common tooling reduces the amount of inventories that are needed to provide the full range of valve types.
Referring to FIG. 2 , the numeral 60 generally designates a manually actuated valve assembly of the present invention. Valve assembly 60 includes valve body 10 and a manual actuation sub-assembly 62 . Manual actuation sub-assembly 62 , as previously noted, includes an actuator 64 , in the form of a stem, for opening and closing the valve and an adapter 66 , which is configured to mount sub-assembly 62 to valve body 10 on plate 38 at mounting surface 42 . As best seen in FIG. 4 , actuator 64 extends through adapter 66 for engagement with the engagement surface of the valve ball to pivot the ball valve about pivot bolt 34 to thereby open or close the valve. Adapter 66 includes an upwardly extending collar 68 with a pair of stops 70 and 72 , which provide the open and close valve positions for the actuator, described more fully below.
Referring to FIGS. 4-6 and 5 A, upper portion 64 a of actuator 64 includes a handle H 1 , H 2 , H 3 , H 4 shown in FIG. 1 , which is rotatably coupled to actuator 64 and mounted thereto a bolt 74 which is threaded into upper end 64 a of actuator 64 and, further, mounted thereon over a washer 76 to thereby lock the handle to the actuator. Similar to stop plate 78 described below, the handle has a non-circular opening for mounting the handle on the non-circular portion ( 64 a ) of actuator 64 . Thus, rotation of the handle about axis 60 a induces rotation of actuator 64 . Also mounted to upper end 64 a of actuator 64 is a stop plate 78 . Stop plate 78 is rotatably coupled to actuator 64 by virtue of the non-circular cross-section of actuator 64 at its upper end 64 a and the non-circular opening 78 a provided in stop plate 78 that mounts stop plate 78 about upper end 64 a of actuator 64 . Stop plate 78 rests on a shoulder 64 b of actuator 64 and, as noted, is rotatably coupled to actuator 64 such that rotation of the handle about vertical axis 60 a causes stop plate 78 to rotate about axis 60 a along with actuator 64 . Stop plate 78 includes an outwardly projecting tab 80 for engagement with stops 70 and 72 of adapter 66 , which limit the rotation of actuator 64 between a first position where tab 80 engages stop 70 and a second position in which tab 80 engages stop 72 , which represent the opened and closed positions of the valve.
Actuator 64 further includes a flange 64 c at a lower end of its medial portion 64 d , which has a larger diameter than the opening 44 of adapter plate 38 , which acts as a stop to limit downward movement of actuator 64 into the valve body and valve ball 14 . In addition, mounted over flange 64 c is a washer 65 so that when adapter 66 is mounted to adapter plate 38 with fasteners 66 a ( FIG. 2 ), flange 64 c is captured between adapter 66 and adapter plate 38 to thereby fix the vertical position of adapter 64 with respect to valve ball 14 . To seal actuator 64 in housing 12 , actuator 64 includes mounted about its lower portion 64 e a seal 64 f , such as an o-ring seal.
To reduce friction, positioned between adapter 66 and the intermediate portion 64 d of actuator 64 is a bushing 82 with an annular lip 84 , which rests on shoulder 86 of adapter 66 . In addition, to assure rotation occurs between the stop plate and adapter 66 , a bearing brake 88 is mounted about the upper end of intermediate portion 64 d , which provides a stationery bearing surface for the stop plate. Referring to FIG. 5A , bearing brake 88 comprises an annular member with a pair of tabs 90 and 92 that are located in recesses 94 and 96 of collar 68 of adapter 66 to rotationally lock brake 88 with respect to adapter 66 . Positioned between bearing brake 88 and adapter 66 is a spring 98 . In the illustrated embodiment, spring 98 comprises a wave washer, which urges brake 88 upward toward the underside of stop plate 78 to maintain friction between stop plate 78 and brake 88 and as a result creates a tight connection between the various parts.
As best seen in FIGS. 4 , 5 A, and 6 , lower end 64 e of actuator 64 includes a cylindrical pin 64 g and an enlarged generally cylindrical body 64 h . Referring to FIG. 4 , cylindrical pin 64 g and body 64 h extend into a slotted recess 14 b in wall of valve ball 14 . As best seen in FIG. 4 , slotted recess 14 b includes a central opening 14 c into which pin 64 g extends and further aligns with pivot bolt 34 . Body 64 h is sized and shaped such that body 64 h can be inserted into recess 14 b and includes a pair of opposed generally planar engagement surfaces 64 i , which are generally parallel and, further, are spaced apart approximately the width of recess 14 b . In this manner, when actuator 64 is rotated about axis 60 a , surfaces 64 i of actuator 64 will bear against the sides of recess 14 b and rotate valve ball 14 about vertical axis 14 a about pin 64 g and bolt 34 to thereby move the valve ball between its opened and closed positions to thereby open or close the valve.
Referring to FIG. 7 , the numeral 160 refers to a slow-close actuated valve assembly. Slow-close actuated valve assembly 160 is of similar construction to manually actuated valve assembly 60 and includes valve body 10 and a slow-close actuation sub-assembly 162 . Slow close actuation sub-assembly 162 is of similar construction to manual actuation sub-assembly 62 but includes additional components to provide a “slow-close” function for the valve assembly.
As best seen in FIGS. 9 and 10 , sub-assembly 162 includes an actuator 164 , an adapter 166 , and a stop plate 178 , similar to the previous embodiment. Further, actuator 164 includes an enlarged flange 164 c , which is captured between adapter 166 and adapter plate 38 of valve body 10 . In the slow-close actuation assembly, mounted to upper end 164 a of actuator 164 is a slow-close device 200 , which includes a plurality of nested annular members 201 , 202 , and 204 , which are mounted to upper end 164 a of coupler 164 on a shaft 206 by an elongated bolt 174 and washer 176 . Shaft 206 is generally cylindrical in shape and includes a non-circular cross-section at its lower end 206 a that inserts into a non-circular opening in member 201 to thereby rotatably couple member 201 and shaft 206 . Further shaft 206 includes an annular flange 206 b that extends between annular members 202 and 204 and is sized to form annular spaces 207 a and 207 b between flange 206 b and member 202 and between flange 206 b and member 204 . These spaces form orifices for a hydraulic fluid, more fully described below. In addition, flange 206 b includes two extended flange portions 206 c ( FIG. 14 ) which have terminal ends to form a pair of chambers 207 c , 207 d , which are in fluid communication with each other through orifices 207 a , 207 b . Further, member 204 includes a fill opening 204 a ( FIG. 12 ) that is in fluid communication with one of the chambers and which allows hydraulic fluid to be introduced into the chambers. After filling, fill opening 204 a is then closed by a set screw. In addition, seals S are provided between each of the members 201 , 202 , and 204 and the shaft to seal the chambers. Consequently, when shaft 206 is rotated in member 202 , the hydraulic fluid creates a resistance to provide the slow-close function, as will be further explained below.
To actuate the slow-close device, slow-close device 200 includes a handle 212 . Annular member 201 includes a slotted opening 208 in its downwardly depending annular wall 210 to receive handle 212 . Handle 212 includes a non-circular transverse opening 212 a for mounting handle 212 about upper portion 164 a of actuator 164 , which similarly has a non-circular cross-section to thereby rotationally couple handle 212 , and in turn annular member 201 , to actuator 164 . In addition, when handle 212 is rotated, shaft 206 , which is rotatably coupled to member 201 also will rotate. In contrast, annular member 202 is fixed relative to adapter 166 by a pin 209 , which extends between respective bores provided in adapter 166 and annular member 202 . As would be understood by those skilled in the art, when handle 212 is rotated, actuator 164 will pivot valve ball 14 about pivot bolt 34 and actuator 164 , with the rotation of handle 212 being resisted by the hydraulic fluid as it passes between the two chambers of the slow-close device through the respective orifices. Again, tabs 180 of the stop plate 178 will limit the angular rotation of actuator 164 between the two stops ( 170 and 172 ) on adapter 166 which correspond to the open and closed positions of the valve.
In this manner, slow close device 200 is an add-on feature that can be mounted on a manual actuation assembly to control the opening and closing of the valve.
Referring to FIGS. 15-17 , the numeral 360 generally refers to a gear actuated valve assembly. Gear actuated valve assembly 160 includes valve body 10 and a gear actuation sub-assembly 362 . Gear actuation sub-assembly 362 similarly mounts to adapter plate 38 at mounting surface 42 of valve body 10 and includes an actuator 364 and a housing 366 , which is adapted to mount sub-assembly 362 to valve body 10 on plate 38 at mounting surface 42 . Actuator 364 is of similar construction to actuators 64 and 164 and includes an upper portion 364 a , an intermediate portion 364 d , and a lower portion 364 e , which engages and pivots valve ball 14 in a similar manner described in reference to the first embodiment.
Referring to FIG. 17 , housing 366 is mounted to adapter plate 38 of valve body 10 by a plurality of fasteners 366 a that extend through lower or base wall 366 b of housing 366 . In a similar manner to actuators 64 and 164 , actuator 364 includes a washer 365 which is mounted about intermediate portion 364 d of actuator 364 and which rests on enlarged flange 364 c of actuator 364 wherein flange 364 c is captured between adapter plate 38 and lower wall 366 b of housing 366 when housing 366 is mounted to plate 38 .
As best seen in FIGS. 17 and 18 , positioned and mounted in housing 366 is a gear sector 378 and a worm gear 380 . Gear sector 378 is mounted to upper end 364 a of actuator 364 by a bolt 374 and washer 376 . Referring to FIG. 19 , sector 378 includes a non-circular opening 378 a so that sector 378 is rotatably coupled to actuator 364 so that when sector 378 is rotated about axis 362 a , actuator 364 will rotate to open or close the valve.
Worm gear 380 is mounted adjacent gear section 378 about a shaft 382 that is rotatably supported in housing 366 to rotatably support worm gear 380 in housing 366 . Worm gear 380 engages sector 378 so that rotational movement of the shaft 382 , which drives worm gear 380 , will drive sector 378 and in turn actuator 364 between open and closed positions, which correspond to the gear stops that limit the rotation of the actuator, for example, to 90°. Optionally and preferably, housing 366 includes a cover 266 c to enclose the actuator drive mechanism. As would be understood by those skilled in the art, an electronic motor or handle or handwheel may be coupled to shaft 382 and mounted externally and, in some cases, remotely from housing 366 . In this manner, sub-assembly 362 may be used as an electric actuation sub-assembly or a handwheel actuation sub-assembly.
Referring to FIGS. 22 and 23 , the numeral 460 generally designates another embodiment of a valve assembly of the present invention. Valve assembly 460 is configured as a twist-lock actuated valve assembly and includes valve body 10 and a twist-lock sub-assembly 462 . Similar to the previous embodiments, twist-lock sub-assembly 462 includes an actuator 464 , which is of similar construction to actuators 364 , 164 , and 64 . Also similar to the previous embodiments, twist-lock sub-assembly 462 is adapted to mount to adapter plate 38 at mounting surface 42 of valve body 10 so that actuator 464 can be extended through adapter plate 38 to selectively rotate valve ball 14 about pivot bolt 34 and actuator 364 . For further details of how actuator pivots valve ball 14 , reference is made to the previous embodiments.
As best seen in FIG. 23 , twist-lock sub-assembly 462 includes an adapter 466 , which fastens to adapter plate 38 by a plurality of fasteners 466 a . Actuator 464 extends through adapter 466 with its lower end 464 e extended through adapter plate 38 for engagement with valve ball 14 and its upper end 464 a extending through a stop plate 478 . Stop plate 478 is mounted in adapter 466 and includes a pair of tabs 480 and 480 b for engagement with stops 470 and 472 provided or formed in adapter 466 in a similar manner to the first and second embodiments. In addition, similar to the previous embodiments, stop plate 478 includes a non-circular opening 478 a which cooperates with a non-circular cross-section of upper portion 464 a of actuator 464 to rotatably couple stop plate 478 to actuator 464 . Also, mounted to upper end 464 a is a lock wedge 480 , a lock elevator 482 , and a cover 484 . Cover 484 supports a rod 486 with a knob 488 and is secured to upper end 464 a of actuator 464 by a bolt 474 and washer 476 . In this manner, when rod 486 is rotated about axis 460 a , valve ball 14 will be moved between its open and closed position.
As best seen in FIGS. 23 and 25 , the distal end of rod 486 a includes an annular groove 486 b for engagement by an upwardly projecting flange 482 a of lock elevator 482 . In this manner, when rod 486 is pushed into cover 484 with a threading action, rod 486 will push elevator 482 inwardly, which has a ramped surface that contacts the ramped surface of wedge 480 so that elevator 482 causes wedge 480 to rise or lift, which causes the actuator to lift or pull up. This upward force includes increased friction between the actuator 464 and adapter 466 , which resists rotation and which locks the valve position.
Referring to FIGS. 27-31 , the numeral 562 represents a rack and sector actuation sub-assembly that is suitable for use with valve body 10 described in reference to the previous embodiments. Similar to the previous embodiments, rack and sector actuation sub-assembly 562 includes an actuator 564 , which is of similar construction to actuators 164 , 364 , and 464 , and an adapter 566 . Therefore, for further details of actuator 564 reference is made to the previous embodiments.
Referring to FIGS. 28 and 29 , adapter 566 includes an upper adapter member 566 a and a lower adapter member 566 b , each with a plurality of mounting holes for receiving fasteners (not shown) for securing adapter 566 to plate 38 at mounting surface 42 of body 10 . Actuator 564 extends through adapter 566 for engagement with valve ball 14 and similarly includes an enlarged mounting flange 564 c and, further, a washer 565 , which are captured between adapter 566 and mounting surface 42 of plate 38 of valve 10 when sub-assembly 562 is mounted to valve 10 .
Lower adapter member 566 b includes an upwardly extending collar 566 c which extends through upper adapter member 566 a , which provides a bearing surface for a gear sector 578 , which is rotatably coupled to upper portion 564 a and is secured thereto by a bolt 574 and washer 576 . Gear sector 578 and upper portion 564 a of actuator 564 have a similar non-circular interface to provide a rotational coupling between the two components. As best seen in FIGS. 28 and 29 , gear sector 578 is driven by a rack 582 , which is rotatably mounted in upper adapter member 566 a by a pair of bushings 582 a and 582 b . Bushings 582 a and 582 b are supported in upwardly extending tabs or flanges 566 d of upper adapter member 566 a . Optionally and preferably, sub-assembly 562 includes an angle bracket 586 , which secures to the lower adapter member 566 b , which by a pair of fasteners 586 a and includes an upwardly projecting flange 588 , which is located and mounted adjacent the teeth of the rack ( 582 ) ( FIG. 29 ).
Accordingly, the present invention provides a valve body that is adapted to accept several actuation sub-assemblies, which provides several advantages as noted above. This single valve body that can be used in several applications provides a great improvement over the prior art and, further, provides a basis on which further actuation assemblies can be modeled.
While several forms of the invention have been shown and described, other forms will now be apparent to those skilled in the art. For example, other types of actuator sub-assemblies may be used, such as pneumatic or hydraulic actuator sub-assemblies. Therefore, it will be understood that the embodiments shown in the drawings and described above are merely for illustrative purposes, and are not intended to limit the scope of the invention which is defined by the claims which follow as interpreted under the principles of patent law including the doctrine of equivalents. | A valve assembly includes a valve body with an inlet, an outlet, and a chamber extending between the inlet and the outlet and an actuation sub-assembly. Positioned in the chamber is a flow restrictor, which is positionable between a valve open position wherein the fluid communication between the inlet and outlet is open and a valve closed position wherein the fluid communication between the inlet and the outlet is closed. The actuation sub-assembly includes a stem for engaging the flow restrictor. When the actuation sub-assembly is mounted to the valve body, the stem extends through the valve body wall for engagement with an engagement surface of the flow restrictor but is removable from engagement with the engagement surface of the flow restrictor without requiring disassembly of the valve body. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an RGB encoder such as is used in a so-called video-CD player or a digital video disc (DVD) player.
2. Description of the Prior Art
An RGB encoder converts R, G and B digital signals into digital luminance, composite and chrominance signals.
In addition, the RGB encoder converts those luminance, composite and chrominance signals into analog values, and outputs the analog luminance, composite and chrominance signals.
A conventional RGB encoder is so constructed as to activate all the three D/A converters for converting digital luminance, composite and chrominance signals into analog values.
Such conventional RGB encoder will not cause a problem in appliances such as a video-CD player or a DVD player of a stay-at-home type, because such appliances are supplied with power from a commercial power line. In portable type appliances, however, since they are supplied with power of a battery, a conventional RGB encoder is defective because no consideration is given to reduction of power consumption.
More specifically, a monitor such as a television set or a liquid crystal display unit works either using only a composite signal or using a luminance signal together with a chrominance signal. In other words, the monitor does not need all of composite, luminance and chrominance signals simultaneously. Therefore, constant output of all these three signals is a waste, leading the encoder to consume more power than necessary.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an RGB encoder which can save power by adapting its power consumption to a condition under which the encoder is used, and to provide an electronic appliance incorporating such an RGB encoder.
To achieve the above object, an encoder of the present invention is provided with RGB input terminals; a circuit for forming digital composite, luminance and chrominance signals based on R, G and B digital signals input through the RGB input terminals; first, second and third D/A converters for converting the digital composite, luminance and chrominance signals into corresponding analog signals; first, second and third output terminals for outputting analog-converted composite, luminance and chrominance signals, respectively; a mode terminal for inputting a mode signal; a selecting circuit for activating required ones of the three D/A converters and deactivating others according to said mode signal.
According to the construction described above, since only selected ones of the three D/A converters are turned on while the other D/A converters are turned off according to the mode signal, the D/A converters that are turned off do not consume power. This leads to reduction of power consumption in the encoder as a whole, and consequently, contributes to saving of battery power, when the encoder is employed in a portable type appliance.
BRIEF DESCRIPTION OF THE DRAWINGS
This and other objects and features of this invention will become clear from the following description, taken in conjunction with the preferred embodiments with reference to the accompanied drawings in which:
FIG. 1 is a block diagram showing an RGB encoder embodying the present invention;
FIG. 2 is a diagram showing the outline of the D/A converter of the present invention;
FIG. 3 is a circuit diagram showing details of cells in the D/A converter of the present invention;
FIG. 4 is a circuit diagram showing the construction of the D/A converter selecting portion of another embodiment;
FIG. 5 is a diagram showing a manner of use of an RGB encoder of the present invention;
FIG. 6 is a perspective view of a television monitor;
FIG. 7 is a diagram showing relationship between the video terminals of the television monitor and the connectors;
FIG. 8 is a diagram showing another manner of use of an RGB encoder of the present invention; and
FIG. 9 is a block diagram for explaining the manner of use of an RGB encoder of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an RGB encoder 1 formed as a one-chip IC. Reference numerals 2, 3 and 4 represent input terminals for inputting R, G and B digital signals. These terminals are connected to an MPEG core chip 30 to receive digital R, G and B signals as shown in FIG. 9, for example. Reference numerals 5a, 5b and 5c represent latch circuits, for latching and outputting the input R, G and B signals R D , G D and B D .
Reference numeral 6 is a circuit for processing the input R, G and B digital signals R D , G D and B D and outputting television signals other than R, G and B signals. This circuit 6 outputs a digital composite signal (S D ) to a signal path 7, a digital luminance signal (Y D ) to a signal path 8, and a digital chrominance signal (C D ) to a signal path 9.
Reference numeral 10 represents a luminance signal forming circuit for forming a digital luminance signal (Y D ) based on the digital R, G and B signals R D , G D and B D . Reference numeral 11 represents a color-difference signal forming circuit for forming digital color-difference signals B-Y and R-Y based on the digital R, G and B signals R D , G D and B D . In a modulation circuit 12, outputs from the color-difference signal forming circuit 11 modulates a carrier supplied by a color carrier generating circuit 13. In an adder circuit 14, a color carrier is inserted as color burst signals at color burst positions of the modulated signal obtained from the modulation circuit 12.
Reference numeral 15 is an adder circuit for adding the luminance signal (Y D ) and the chrominance signal (C D ), and for outputting a resultant signal as a composite signal (S D ). Reference numerals 16, 17 and 18 represent a first, a second and a third D/A converters for converting the input digital composite signal (S D ), luminance signal (Y D ) and chrominance signal (C D ) into analog composite signal (S A ), luminance signal (Y A ) and chrominance signal (C A ), and for outputting thus converted signals.
Reference numerals 19, 20 and 21 are output terminals for outputting outputs from the D/A converters 16, 17 and 18. These terminals are connected to a television monitor 33, if necessary, as shown in FIG. 9. Reference numeral 22 represents a switch for switching on and off a power supply +B. The switch 22 is switched between a terminal (a) position and a terminal (b) position depending on a mode signal fed from a mode terminal 23. The switch 22 is formed as a semiconductor switch.
FIG. 2 shows an example of the D/A converter 16 as representing said D/A converters 16, 17 and 18. In the figure, reference numeral 24 is a signal processing circuit, reference numeral 25 represents a horizontal drive circuit, reference numeral 26 represents a vertical drive circuit. Reference numeral 27 represents cells arranged in a matrix.
FIG. 3 shows details of five cells extracted from the cells 27. Here T 11 , T 12 , T 13 , T 21 and T 22 represent transistors that form cells. Reference numerals 41, 42 and 43 are terminals for receiving drive signals from the horizontal drive circuit 25. Reference numerals 51, 52 and 53 are terminals for receiving drive signals from the vertical drive circuit 26.
A 11 , A 12 , A 13 , A 21 and A 22 represent AND gates. Reference numeral 44 represents a power line. The power line 44 is deactivated when it is not supplied with +B from the switch 22, and it is activated when it is supplied with +B from the switch 22.
Assume now that the terminal 41 is given a high level and the terminal 51 is given a high level. In this case, the AND gate A 11 outputs "1", turning on the transistor T 11 . As a result, a current flows from the power line 44 to an output line 45. Levels ("1" and "0") at the terminals 41, 42, 43, 51, 52 and 53 are determined depending on how large the input signal is, and each transistor is turned on or off according to the levels at those terminals. As more transistors are turned on, the output current increases. A current in the output line is converted into a voltage as necessary.
In a situation where the outputs of the encoder 1 of this embodiment are connected to a stay-at-home type television monitor 60 as shown in FIG. 5, the encoder 1 will most probably be incorporated in a stay-at-home type video-CD player or DVD player, being fed with power from a commercial power line. In a case like this, the mode terminal 23 is given a high level, and the switch 22 is switched to the terminal (b) position. Thus, all the D/A converters 16, 17 and 18 are activated, and accordingly, all of the composite signal (S A ), the luminance signal (Y A ) and the chrominance signal (C A ) are supplied to the television monitor 60. In such a case, the television monitor 60 should be so constructed, for example, as to preferably use the composite signal (S A ), neglecting the luminance signal (Y A ) and the chrominance signal (C A ).
FIG. 6 is a perspective view of a television monitor 60, which has on its side a terminal 62 for the composite signal and a terminal 63 for the luminance signal and the chrominance signal. FIG. 7 shows these terminals 62 and 63, and connectors 64 and 65 connected thereto. The connectors 64 and 65 are attached to the ends of cables or the like, of which the other ends are connected to the encoder 1 or an appliance which includes such an encoder.
In contrast, in a situation where the encoder 1 is incorporated in a portable type appliance (video-CD player or DVD player) 80 as shown in FIG. 8, the appliance may be connected to a liquid crystal display monitor 81. In this case, the liquid crystal display monitor 81 has only a terminal 82 for the composite signal.
Accordingly, as to the D/A converters in the encoder 1, only the D/A converter 16 needs to be activated, while the D/A converters 17 and 18 are left deactivated. To achieve this, the mode terminal 23 is given a low level, and the switch 22 is switched to the terminal (a) position. Thus, it is possible to save power consumed in the encoder 1. Incidentally, each of the D/A converters 16, 17 and 18 requires a current of approximately 30 mA, and the other portions of the encoder require a current of approximately 30 mA in total.
Therefore, since a D/A converter consumes considerable power, it is meaningful to deactivate D/A converters which are not in use, especially in a portable type appliance. It is to be noted that, in FIG. 8, the liquid crystal display 81 is incorporated into the appliance 80.
Selection of the D/A converters 16, 17 and 18 by the switch 22 may also be performed as shown in FIG. 4. There, the terminal (a) of the switch 22 is connected to the first D/A converter 16, and the terminal (b) is connected to the second and the third D/A converters 17 and 18. Such connection provides two modes: a mode in which the composite signal (S A ) is output, and a mode in which the luminance signal (Y A ) and the chrominance signal (C A ) are output. Although the description above of this embodiment assumes use of current-matrix type D/A converters, typical D/A converters of other types can be used instead.
As described above, according to the present invention, it is possible to save power, because the power consumed by an encoder can be adapted to a condition under which the encoder is used, and this is effective especially when the encoder is used in a portable type appliance. | An encoder converts digital RGB signals into analog television signals. This encoder forms digital composite, luminance and chrominance signals based on digital signals input through an RGB input terminal. The encoder has a first, a second and a third D/A converters for converting digital composite, luminance and chrominance signals into corresponding analog signals. The encoder is provided with a switch for activating required ones of the three D/A converters and deactivating others of the D/A converters. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates to certain isoflavonoid compounds, compositions containing the same, and therapeutic uses of those compounds.
BACKGROUND OF THE INVENTION
[0002] In recent years there has been increasing attention on phytoestrogens particularly isoflavonoids. Isoflavonoids or isoflavones (as they are also known) are a class of phytoestrogens which are found in plants and which are based on a diphenolic ring structure. Due to their structure, it has been documented that they are able to bind to oestrogen receptors on animals including humans. A small subgroup of isoflavones are known to display oestrogenic activity, as well as anti-carcinogenic, antifungal, antiproliferative properties and anti-oxidative effects. These oestrogenic isoflavones (genistein, biochanin, daidzein, glycitein and formononetin) are predominantly found in plants which are members of the Leguminosae family.
[0003] Most legumes have been found to contain at least one or more of these oestrogenic isoflavones, with the richest sources being soya beans, lentils, clover, chick peas, alfalfa and other beans. Most human diets contain low to moderate levels of oestrogenic isoflavones. In typical diets in developed Western countries, the dietary intake of the oestrogenic isoflavones is low and often negligible, as legumes are not relied upon strongly as a source of protein, being instead replaced by animal products.
[0004] However, the dietary intake of oestrogenic isoflavones from traditional diets of Eastern and developing countries such as India, China and South America is moderate to high, given the fairly high dietary intake of beans including soya beans, kidney beans, lima beans, broad beans, butler beans, chick peas and lentils. The presence of such dietary levels of oestrogenic isoflavones is confirmed by detection of the amounts of the isoflavones daidzein, genistein, glycitein, formononetin and biochanin and their metabolites in human urine. People with high legume intake in their diets excrete substantially higher amounts of isoflavone metabolites in their urine than people with largely omnivorous or low-legume diets.
[0005] After ingestion, isoflavones undergo varying degrees of metabolism within the digestive system. The naturally occurring, water soluble glycosidic form of isoflavone undergoes hydrolysis to the aglycone form in the gut, while biochanin and formononetin are demethylated by bacterial fermentation to genistein and daidzein respectively. It appears that the majority of the aglycone isoflavones then undergo fermentation by intestinal bacteria to produce end products including equol, dehydroequol, O-desmethylangolensin (ODMA), dihydrodaidzein, tetra-hydrodaidzein and dihydrogenistein. The isoflavones, their metabolites and derivatives circulate around the body and are mainly excreted in the urine, in which they can then be detected.
[0006] As stated above, given the presence of high levels of isoflavones in legumes, particularly soya beans, and the knowledge that the isoflavones are fermented or metabolised by intestinal or bowel bacteria to produce isoflavone metabolites, research has been conducted into microbial fermentations of soybeans and has demonstrated production of metabolites including 6,7,4′-trihydroxyisoflavone (hereinafter called Factor 2) and other polyhydroxylated isoflavonoids.
[0007] Traditional Asian food products such as tempeh, tofu, miso etc are foods produced from soybeans by fermentation mainly by fungi of the genus Rhizopux. It has been shown that several bacteria species may also be involved in tempeh production. For traditional tempeh fermentation, the soybeans are cooked, dehulled and soaked overnight. A spontaneous bacterial acidification occurs during this phase. In industrial tempeh fermentation processes, the cooked soybeans are acidified with lactic acid. After the soaking process, the soybeans are cooked again and incubated with microbial inocula for 2 days.
[0008] In unfermented soybeans, the isoflavones genistein, daidzein and glycitein predominantly occur as isoflavone glucosides and acylglucosides. It has been shown that during tempeh fermentation, the isoflavone aglycones are liberated from the conjugates and accumulate in the tempeh product. Further findings have shown that during fermentation the isoflavone 6,7,4′-trihydroxyisoflavone (termed “Factor 2” by Gyorgy et al. in Nature (1964) 203, 870-872), also accumulates.
[0009] It was previously thought that the fungi of the genus Rhizopus were responsible for the formation of Factor 2 from either daidzein or glycitein. However, subsequent studies on the metabolism of daidzein and glycitein by Klus et al., 1993 showed that isolates of Brevibacterium epidermidis and Micrococcus luteus, which were isolated from Indonesian tempeh samples, readily transform glycitein, forming Factor 2. A third tempeh-derived bacterium. Microbacterium arborescens, metabolized daidzein, producing both Factor 2 and glycitein. More recently, Klus, K. and Barz, W. Arch. Microbiol. 164:428-434, (1995) investigated five other bacterial isolates, which were isolated from tempeh samples containing Factor 2 and were classified as Micrococcus or Arthrobacter strains, for their ability to metabolize daidzein and glycitein by hydroxylation or O-demethylation reactions. Their results show that a number of polyhydroxylated isoflavones were formed, hydroxylated at three or four of positions 6,7,8,3′ and 4′. Of these Factor 2 was the major product produced by most of the microbial strains. The bacterial strains only hydroxylated but did not degrade the substrates namely daidzein or glycitein. The compounds of the present invention were not identified by Klus and Barz, however,
[0010] Various polyhydroxylated isoflavones known in the prior art are known to exhibit anti-inflammatory and anti-allergenic activity and to express anticarcinogenic properties due to inhibition of protein tyrosine kinases, which play a key role in cellular pathways in tumour cell growth. In in vitro tests, these isoflavones also inhibit the growth of human leukemia (Makishima et al., 1991) and human breast cancer cells (Hirano et al, 1989; Peterson and Barnes, 1991). In essence, the polyhydroxylated isoflavones occurring as dietary factors in fermented soybean products are putative causes of the lower incidence of cancer-related diseases in Asian populations, and have been used in the treatment of a variety of cancers including breast cancer, ovarian cancer, large bowel cancer; and prostatic cancer.
[0011] Other therapeutic uses of the oestrogenic isoflavones which have been disclosed include their use as therapeutics for menopausal symptoms and osteoporosis (WO 98/50026, European patent application 0135172, U.S. Pat. No. 5,498,631 in the name of Gorbach el al); pre-menstrual symptoms; Reynauds Syndrome; rheumatic diseases; Buergers Disease; coronary artery spasm; migraine headaches; benign prostatic hypertrophy and hypertension.
[0012] As stated above, isoflavonoids are natural plant compounds which possess antitumorigenic properties. Of all oestrogenic isoflavones of which daidzein, genistein, formononetin and biochanin-A are the most well known, it has been shown that individually, genistein is the most potent inhibitor (IC50=25-33 μM) of the proliferation of MCF-7 cells induced by a number of environmental chemicals such as 1-(o-chlorophenyl)-1-(p-chlorophenyl)-2,2,2-trichloroethane, 5-octylphenol and 4-nonylphenol as demonstrated recently by Verma S P and Goldin B R ( Nutrition & Cancer 30(3):232-9,1998).
[0013] The same authors also noted that a mixture of isoflavones was the most potent inhibitor against the induced proliferation. However, as in the case of other research workers they found that genistein, biochanin A, equol and to some extent daidzein at <10 μM can enhance the growth of MCF-7 cells.
[0014] There is therefore a need for novel isoflavonoids which can inhibit the proliferation of cancer cells but which do not enhance their growth at low concentrations, and which exhibit other therapeutic properties.
OBJECTS OF THE INVENTION
[0015] It is therefore an object of the present invention to provide novel isoflavonoid compounds.
[0016] It is another object of the present invention to provide compositions including food and drink compositions containing novel isoflavonoid compounds.
[0017] It is a further object of the present invention to utilise novel isoflavonoid compounds in treating hormone dependent conditions and other diseases and disorders.
SUMMARY OF THE INVENTION
[0018] Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising” or the term “includes” or variations thereof, will be understood to imply the inclusion of a staled element or integer or group of elements or integers but not the exclusion of any other element or integer or group of elements or integers.
[0019] According to a first aspect of the present invention there is provided a compound of formula I or formula II
[0000]
[0000] in which
A is selected from the group consisting of
[0020]
[0000] one of R 1 and R 2 is selected from H, OH and OCH 3 , and the other of R 1 and R 2 is selected From OH and OCH 3 ;
one of R 3 and R 4 is selected from H, OH and OCH 3 , and the other of R 3 and R 4 is selected from OH and OCH 3 ;
provided that at least one of the pairs R 1 , R 2 and R 3 , R 4 are both OH;
R 5 is selected from OH and OCH 3 ; and
[0021]
denotes a single or double bond,
or a pharmaceutically acceptable salt or prodrug thereof.
[0022] In one form, the invention relates to compounds of formula (I) or (II) as defined hereinabove, wherein
[0000] one of R 1 and R 2 is selected from H and OH, and the other of R 1 and R 2 is OH;
one of R 3 and R 4 is selected from H and OH, and the other of R 3 and R 4 is OH;
provided that at least one of the pairs R 1 , R 2 and R 3 , R 4 are both OH;
R 5 is OH; and
[0023]
denotes a single or double bond.
[0024] In another form, the invention relates to compounds of the formula (IA) or (IIA)
[0000]
[0000] wherein A is as defined hereinabove
R 2 is H, and R 1 is selected from OH and OCH 3 ;
R 3 and R 4 are each OH;
R 5 is selected from OH and OCH 3 ; and
[0025]
denotes a single or double bond.
[0026] In a further form, the invention relates to compounds of the formula (IB) or (IIB)
[0000]
[0000] wherein A is as defined hereinabove
R 1 and R 2 are each OH;
R 4 is H, and R 3 is selected from OH and OCH 3 ;
R 5 is selected from OH and OCH 3 ; and
[0027]
denotes a single or double bond.
[0028] Examples of preferred compounds of the invention are:
[0029] (i) 4′,6,7-trihydroxydihydroisoflavone having the structure (III):
[0000]
[0000] (hereinafter referred to as Compound B);
[0030] 5-hydroxy-O-demethylangolesin (5-hydroxy-O-Dma) [1-(2,4,5-trihydroxyphenyl)-2-(4-hydroxyphenyl)-propan-1-one] having the structure (IV):
[0000]
[0000] (hereinafter referred to as Compound A);
[0031] 3′-hydroxy-O-demethylangolesin (3′-hydroxy-O-Dma) [1-(2,4,dihydroxyphenyl)-2-(3,4-dihydroxyphenyl)-propan-1-one] having the structure (V):
[0000]
[0032] 3′-hydroxy-O-demethyldehydroangolesin (3-hydroxydehydro-O-Dma) [1-(2,4-dihydroxyphenyl)-2-(3,4-dihydroxyphenyl)-prop-2-en-1-one] having the structure (VI):
[0000]
[0033] 3′-hydroxy-dihydrodaidzein having the structure (VII):
[0000]
[0034] 5-hydroxy-2-dehydro-O-Dma [1-(2,4,5-trihydroxyphenyl)-2-(4-hydroxyphenyl)-prop-2-en-1-one] having the structure (VIII):
[0000]
[0035] or pharmaceutically acceptable salts or prodrugs thereof.
[0036] A third aspect of the present invention provides a composition comprising one or more compounds of the formulae I or II as previously defined, in association with one or more pharmaceutically acceptable carriers, adjuvants, diluents and/or excipients.
[0037] Typically, one or more of the compounds of structures (III) to (VIII) may be used in a composition of the third aspect of the present invention.
[0038] A fourth aspect of the present invention is a food or drink composition, which contains one or more compounds of the formulae I or II.
[0039] Typically, the food or drink composition contains one or more of the compounds of structures (III) to (VIII).
[0040] According to a fifth aspect of the present invention there is provided a method for the treatment, prophylaxis, amelioration, defence against, and/or prevention of menopausal syndrome including depression, anxiety, hot flushes, night sweats, mood swings, and headache; osteoporosis; rheumatic diseases; atherosclerosis; premenstrual syndrome, including fluid retention, cyclical mastalgia, and dysmenorrhoea; coronary artery spasm; vascular diseases including Reynauds Syndrome; Buergers Disease; migraine headaches; hypertension; benign prostatic hypertrophy; all forms of cancer including breast cancer, endometrial cancer, prostatic cancer, uterine cancer, ovarian cancer, testicular cancer, large bowel cancer; Alzheimers disease; inflammatory diseases including Crohns disease, inflammatory bowel disease, ulcerative colitis; baldness including male pattern baldness; psoriasis; acne; and diseases associated with oxidant stress including myocardial infarction, sunlight induced skin damage, arthritis, or cataracts, which method comprises administering to a subject a therapeutically effective amount of one or more compounds of the formulae I or II as previously defined, either alone or in association with one or more pharmaceutically acceptable carriers, diluents, adjuvants and/or excipients.
[0041] According to a related sixth aspect of the present invention there is provided a method for the treatment, prophylaxis, amelioration, defence against, and/or prevention of hormone-dependent conditions including hormone dependent cancers such as breast cancer, hormone dependent cardiovascular disorder and hormone dependent menopausal disorders comprising administering to a subject a therapeutically effective amount of one or more compounds of the formulae I or II as previously defined, either alone or in association with one or more pharmaceutically acceptable carriers, diluents, adjuvants and/or excipients.
[0042] Typically, one or more of the compounds of structures (III) to (VIII) may be used in the method of treatment, prophylaxis, amelioration, defence against, and/or prevention of any one or more of the diseases of the fifth or sixth aspects of the invention.
[0043] A seventh aspect of the present invention is the use of one or more compounds of the formulae I or II for the manufacture of a medicament for the treatment, amelioration, defence against, prophylaxis and/or prevention of one or more of the diseases set out in the fifth or sixth aspects of the invention above.
[0044] It is typical that one or more of the compounds of structures (III) to (VIII) are employed in the seventh aspect of the present invention.
[0045] A related eighth aspect of the present invention is use of one or more compounds of the formulae I or II in the treatment, amelioration, defence against, prophylaxis and/or prevention of one or more of the diseases set out in the fifth or sixth aspects of the invention above.
[0046] Typically, one or more of the compounds of structures (III) to (VIII) are used in the eighth aspect of the invention.
[0047] A ninth aspect of the present invention is a microbial culture or a food or drink composition containing at least one microbial strain which microbial strain is capable of producing one or more compounds of the formulae I or II from daidzein and/or glycitein.
[0048] Typically, said microbial strain produces one or both of compounds A and B.
[0049] Typically, the microbial strain is in the form of a purified culture, which may optionally be admixed and/or administered with one or more other cultures which produce any one or more compounds of the formulae I or II, more typically one or more of the compounds of structures (III) to (VIII).
[0050] A tenth aspect of the present invention provides a process for producing a compound of any one of formulae I or II by microbial fermentation of daidzein or glycitein with one or more microbial organisms selected from the group consisting of Lactobacilli; Clostridium perfingens; Bacteroids including B. vulgatus, B. thetaiotaomicron, B. distasonis; Candida albicans and other yeast; Anaerobic cocci including Ruminococcus, Eubacterium, Peptostreptococcus (such as P. productus found in stools), Clostridium, Bifidobacteria (such as B. adolascentis, B. infantis, and B. longum ), Peptococcus, Veillonella, Acidaminococcus, and Streptococcus; Anaerobic streptococci; Gram-negative facultative bacteria; Aeromonas such as A. hydrophila; Alcaligenes sp; Citrobacter sp; Enterobacter sp including E. liquefaciens and E. aerogenes; Escherichia sp, E. coli; Hafnia sp; Klebsiella sp; Morganella sp such as M. morganii; Proteus sp; Pseudomonas sp; Providencia sp; Aerococcus viridans; Bacillus sp; Corynebacterium sp; Micrococcus sp such, as M. luteus; Nocardia sp; Pediococcus sp; Staphylococcus sp including S. aureus and S. epidermidis; Fusobacterium including F. gonidiaformans, F. mortiferum, F. necrogenes, F. necroforum and F. russii; Butyrivibrio such as B. fibrisolvens; Actinomyces; Arachnia-Propionibacterium; Arthrobacter sp such as A. agilis, A. aurescens, A. pascens, A. oxydans, A. nicotinae and A. cummins; Brevibacterium sp such as B. epidermidis; and Microbacterium sp such as M. arborescens.
[0051] An eleventh aspect of the present invention provides a method for the treatment, prophylaxis, amelioration, defence against, and/or prevention of menopausal syndrome including depression, anxiety, hot flushes, night sweats, mood swings, and headache; osteoporosis; rheumatic diseases; atherosclerosis; premenstrual syndrome, including fluid retention, cyclical mastalgia, and dysmenorrhoea; coronary artery spasm; vascular diseases including Reynauds Syndrome; Buergers Disease; migraine headaches; hypertension; benign prostatic hypertrophy; all forms of cancer including breast cancer, endometrial cancer, prostatic cancer, uterine cancer, ovarian cancer, testicular cancer, large bowel cancer; Alzheimers disease; inflammatory diseases including Crohns disease, inflammatory bowel disease, ulcerative colitis; baldness including male pattern baldness; psoriasis; acne; and diseases associated with oxidant stress including myocardial infarction, sunlight induced skin damage, arthritis, or cataracts, which method comprises administering to a subject a therapeutically effective amount of Factor 2 as previously defined, either alone or in association with one or more pharmaceutically acceptable carriers, diluents, adjuvants and/or excipients.
[0052] According to a related twelfth aspect of the present invention there is provided a method for the treatment, prophylaxis, amelioration, defence against, and/or prevention of hormone-dependent conditions including hormone dependent cancers such as breast cancer, hormone dependent cardiovascular disorder and hormone dependent menopausal disorders comprising administering to a subject a therapeutically effective amount of Factor 2 as previously defined, either alone or in association with one or more pharmaceutically acceptable carriers, diluents, adjuvants and/or excipients.
[0053] The invention also provides in a thirteenth aspect the use of Factor 2 for the manufacture of a medicament for the treatment, prophylaxis, amelioration, defence against, and/or prevention of menopausal syndrome including depression, anxiety, hot flushes, night sweats, mood swings, and headache; osteoporosis; rheumatic diseases; atherosclerosis; premenstrual syndrome, including fluid retention, cyclical mastalgia, and dysmenorrhoea; coronary artery spasm; vascular diseases including Reynauds Syndrome; Buergers Disease; migraine headaches; hypertension; benign prostatic hypertrophy; all forms of cancer including breast cancer, endometrial cancer, prostatic cancer, uterine cancer, ovarian cancer, testicular cancer, large bowel cancer; Alzheimers disease; inflammatory diseases including Crohns disease, inflammatory bowel disease, ulcerative colitis; baldness including male pattern baldness; psoriasis; acne; and diseases associated with oxidant stress including myocardial infarction, sunlight induced skin damage, arthritis, or cataracts.
[0054] A fourteenth aspect of the invention further provides the use of Factor 2 for the manufacture of a medicament for the treatment, prophylaxis, amelioration, defence against, and/or prevention of hormone-dependent conditions including hormone dependent cancers such as breast cancer, hormone dependent cardiovascular disorder and hormone dependent menopausal disorders.
[0055] A fifteenth aspect of the present invention provides a process for the manufacture of Compound A, said process including:
i) reacting 2-(p-methoxyphenyl)propionic acid with 1,3,4-trimethoxy benzene to obtain 2,4,5,4′-tetramethoxy-α-methyldesoxybenzoin; and ii) demethylating said 2,4,5,4′-tetramethoxy-α-methyldesoxybenzoin to form 2,4,5,4′-tetrahydroxy-α-methyldesoxybenzoin.
[0058] A sixteenth aspect of the present invention provides a compound when produced by the process of the fifteenth aspect of the invention outlined above.
[0059] The present invention is based upon the identification of novel oestrogenic isoflavone metabolite compounds, exemplified by the isoflavonoid phytoestrogens of structures (III), (IV) and (V). These compounds have been identified in the urine of the human adult consuming a diet rich in phytoestrogen content. While not wishing to be bound by theory, it is postulated by the present inventor that the identification of the compounds of structures (III), (IV) and (V) provides evidence for the existence of a previously undiscovered pathway in the mode of metabolism of daidzein and/or glycitein.
[0060] The identification of the compounds of structures (III), (IV) and (V) observed for the first time in the urine of adult humans who ingested soya cake containing daidzein, genistein and glycitein provides evidence to suggest that the compounds of structures (III), (IV) and (V) are products of microbial transformations of daidzein or glycitein. In view of the fact that one of these metabolites, namely compound A, was found in large amounts commensurate to the amount of daidzein ingested compared with glycitein appears that compounds A and B may also be metabolites of daidzein after hydroxylation of ring A. The results of Klus and Barz (1995) referred to above support this hypothesis since these authors demonstrated that a number of microbial species ( Micrococcus, Arthrobacter, Brevibacterium ) are capable of converting daidzein and glycitein to give Factor 2, the most probable precursor of compounds A and B.
[0061] The compounds of Formulae I and II of the present invention, all of which include a vicinal diol substitution, show significant therapeutic activity. In particular, it has been shown that compounds of the invention inhibit the proliferation of MCF-7 and other ceils without significant enhancement of their growth at low concentrations. The vicinal diol substitution is provided by at least one of the following: 6,7-dihydroxy substitution in the benzopyran moiety of structure (I); 3′,4′-dihydroxy substitution in the 3-phenyl substituent in structure (I); or 3,4-dihydroxy substitution and/or 3′,4′-dihydroxy substitution in structure (II). It is speculated that it is the presence of this vicinal diol substitution in the compounds of the invention which confers on them their surprisingly high biological activity.
DETAILED DESCRIPTION OF THE INVENTION
[0062] Compounds of the invention may be obtained by microbial fermentation of suitable naturally-occurring oestrogenic isoflavones, or by chemical synthesis.
[0063] For microbial fermentation, a plant source of naturally-occurring oestrogenic isoflavones is typically used.
[0064] Typically, plant sources for oestrogen isoflavone precursors of the compounds of the invention are any leguminous plant including various species of Acacia, ground nut, alfalfa, lentil and ground pea. Also typically, such plant sources include:
[0000] Trefolium species including parnassi, repens, pallescens, nigrescens, physodes, resupinatum, campestre, arvense, stellatum, cherleri, pignantii, alpestre, pratense, angustifolium, subterraneum and glomeratum, Medicago species including lupulina, falcata, orbicularis, polymorpha, disciformis, minima, and sativa, Cassia species including occidentalis and floribunda, Lupinus species including angustifolium and albus, Vivia species including sativa and monantha and Galega species including officinalis, or mutant strains of any one the foregoing. Beans such as jumping bean, sword bean, broad bean, yam bean, kidney bean, soya bean and butter bean are also a favourable source of for oestrogen isoflavone precursors of the compounds of the invention. The oestrogenic isoflavones are mainly found in the leaves and fruit of the plant, and also in the roots.
[0065] Typically, the compounds of interest which are secreted by microbial cultures or organisms are detected by GC-MS (gas chromatography-mass spectrometry).
[0066] These organisms are used in microbial fermentation to produce compounds of formulae I-II given above. Typically, the organisms are selected from one of the following classes:
[0000] Lactobacilli; Clostridium perfingens; Bacteroids including B. vulgatus, B. thetaiotaomicron, B. distasonis; Candida albicans and other yeast; Anaerobic cocci including Ruminococcus, Eubacterium, Peptostreptococcus (such as P. productus found in stools), Clostridium, Bifidobacteria (such as B. adolescentis, B. infantis, and B. longum ). Peptococcus, Veillonella, Acidaminococcus, and Streptococcus; Anaerobic streptococci; Gram-negative facultative bacteria: Aeromonas such as A. hydrophila; Alcaligenes sp; Citrobacter sp; Enterobacter sp including E. liquefaciens and E. aerogenes; Escherichia sp. E. coli; Hafnia sp; Klebsiella sp; Morganella sp such as M. morganii; Proteus sp; Pseudomonas sp; Providencia sp; Aerococcus viridans; Bacillus sp; Corynebacterium sp; Micrococcus sp such as M. luteus; Nocardia sp; Pediococcus sp; Staphylococcus sp including S. aureus and S. epidermidis; Fusobacterium including F. gonidiaformans, F. mortiferum, F. necrogenes, F. necroforum and F. russii; Butyrivibrio such as B. fibrisolvens; Actinomyces, Arachnia-Propionibacterium; Arthurobacter sp such as A. agilis, A. aurescens, A. pascens, A. oxydans, A. nicotinae and A. cummins; Brevibacterium sp such as B. epidermidis; and Microbacterium sp such as M. arborescens.
[0067] Typically, non-pathogenic organisms selected from the above organisms such as Micrococcus sp and Arthrobacter sp may be used directly in food and/or drink compositions such as dairy formulations so as to provide compounds of the formulae of the invention. The drink/food compositions also need to contain a phytoestrogen source such as soya.
[0068] Microbial conversion of Daidzein and Glycitein to Factor-2 can be effected using the following microbial organisms: Arthrobacter including agilis, aurescens, pascens, oxydans, nicotinae, and cumminsii; Brevibacterium epidermidis (converts glycitein to Factor 2); Micrococcus luteus (converts glycitein to Factor 2), Microbacterium arborescens (converts daidzein lo Factor 2 & glycitein), Streptomyces sp roseolus (converts daidzein/glycitein to 8,3′-dihydroxy-6,7,4-trimethoxyisoflavone or daidzein/glycitein to 7,8,4′ & 7,3′,4′-trihydroxyisoflavones, depending on culture medium). The various microbial conversions are disclosed in detail in Klaus, K. and Barz, W.: Arch. Microbiol. 164 (1995) 428-434; Klaus. K., Borger-Papendorf, G. and Barz, W.: Biochemistry 34(4) (1993) 979-981; Mackenbrock, K and Barz. W.: Naturforsch. 38c (1983) 708; Chimura, H. et al; J. Antibiot. 28 (1975) 619-626; Funayama, S. et al: J. Antibiot. 42 (1989) 1350-1355 and Komiyama, K. et al: J. Antibiot. 42 (1989) 1344-1349, the contents of all of which are incorporated herein by reference.
[0069] Without wishing to be bound by theory, the present inventor hypothesises that the metabolic pathways of catabolism of factor 2 obtained from glycitein or daidzein are as shown in Scheme 1 below. Methylene unit (MU) values of the metabolites under the gas chromatographic conditions described in Example 1 are shown.
[0000]
[0070] An alternative source of compounds of the present invention is chemical synthesis. Conveniently, Factor 2 or a naturally-occurring isoflavone such as glycitein may be utilised as starting material. Schemes 2A and 2B demonstrate possible synthesis pathways of compounds of the invention utilising glycitein as the starting material. In Scheme 2A, compounds 2 and 4 may be obtained from glycitein by reduction with lithium aluminium hydride as described in Example 1. A mixture of compounds 3, 5 and 7 identified Scheme 2A may be obtained from compound 8 as shown in Scheme 2B.
[0000]
[0000]
[0071] Compounds of the equol or dehydroequol series may also be prepared from the corresponding dihydroisoflavone (exemplified by compound 2 in Scheme 2a) by reduction of the carbonyl and dehydration of the resulting alcohol to give a compound of the dehydroequol series, and optionally catalytically hydrogenating the double bond in the pyran ring to yield the corresponding compound of the equol series.
[0072] Unlike the isoflavonoid metabolites of the daidzein and genistein series, those of glycitein have the synthetic advantage that the vicinal hydroxyl groups in the A-ring allow a number of protective functional groups such as the ketals and boronates to be formed easily. In the scheme (Scheme 3) below, the synthesis of compounds of Formula II is demonstrated using a 1,2,4-benzenetriol substrate which, has been protected as an n-butyl boronate derivative formed using commercially available n-butylboronic acid according to methods adopted in similar protective reactions [Joannou, G. E. and Reeder, A. Y., Steroids 61 11-17. (1996)]. Other alkyl boronates can be used.
[0073] Synthesis of 4′ Methoxy-5-Hydroxy-O-Dma and Similar Molecules
[0000]
[0074] In Scheme 3, one of R 1 and R 2 is H, OH or OCH 3 and the other is OH or OCH 3 . For the synthesis of compounds of Formula II in which is OCH 3 , the free hydroxyl group in the boronate intermediate shown above may be methylated, for example by reaction with methyl iodide or methyl sulfate. It will be appreciated that when R 1 or R 2 is OH, it may require protection. When R 1 and R 2 are both OH, they may be protected as a cyclic boronate, ketal or carbonate.
[0075] Instead of using n-butylboronic acid, formation of protective functional groups may alternatively be achieved using cyclic carbonates, cyclic acetals or ketals as shown in Scheme 4A below. Partial methylation can also be used as shown in Scheme 4B below. Other protective groups for catechols are described in Chapter 3 of Greene, T. W. and Wuts, P. G. M.: Protective Groups in Organic Synthesis (2 nd Edition) (1991) John Wiley & Sons, Inc. USA; the disclosure of which is incorporated herein by reference. Compounds of the invention in which R 1 is H and R 2 is OH or OCH 3 or in which R 1 and R 2 are both OH or OCH 3 may be synthesised by analogous procedures to that shown in Scheme 4A but starting with 2-(3-methoxyphenyl)propanoic acid or 2-(3,4-dimethoxyphenyl)propanoic acid instead of the corresponding 4-methoxyphenyl derivative. Similarly, compounds of formula (II) in accordance with this invention, in which one of R 3 and R 4 is H, may be prepared by an analogous procedure beginning with reaction of resorcinol or hydroquinone, suitably protected, with poly phosphoric acid.
[0000]
[0000]
[0076] Furthermore formation of cyclic protective groups such as those described above will allow the synthesis of a number of the isoflavonoid compounds proposed which are normally difficult to obtain synthetically as in the case of the tetrahydro, dehydro and equol analogues of glycitein or its demethylated analogues. A schematic representation (Scheme 5) is given below using 4′,6,7-trihydroxyglycitein as an example.
[0000]
[0077] When necessary, hydroxyl groups in the compounds shown in Schemes 1-5 above, may be methylated and/or protected and deprotected, to give other compounds of formula I or II. Suitable protecting groups are described in the work of Greene and Wills referenced above.
[0078] Compound A may be prepared by the following synthetic scheme 6:
[0000]
[0079] Compound B and related compounds of formula (I) or (II) may be prepared as shown in Scheme 7, in which R is CH 3 , R′ is C 2 H 5 , R 1 -R 4 are each H, OH or OCH 3 , and R′ 1 -R′ 4 are each H or OH, subject to the proviso that in the final product of formula (I) or (II) R′ 1 and R′ 2 are both OH and/or R′ 3 and R′ 4 are both OH.
[0000]
[0080] In the above Scheme 7, the base is typically an organic amine, such as dimethylamine, or an alkali metal hydroxide, carbonate or bicarbonate.
[0081] In the synthesis of 4′,6,7-trihydroxyisoflavone (5-deoxydihydroglycitein) shown in Scheme 7 above, the two intermediates obtained in the penultimate step prior to the demethylation with BBr 3 arc not easily separated. However, it was found that a simple recrystallization procedure using methanol/water provided a quick method of separation and purification of the two intermediates. A similar procedure may be applied to the isolation of the methylated precursors of daidzein and genistein, namely formononetin and biochanin A which are present in clover and soya. Complete methylation of formononetin and biochanin A may further enhance the process of recrystallization of these two isoflavonoid precursors. Isolated formononetin or its fully methylated analogue can be used as a substrate for the chemical or microbial transformations to give Factor 2 or any of the compounds of Formula I or II defined above.
[0082] As an example, formononetin or its methylated analogue may be isolated from a rich source such as clover or soya for subsequent microbial transformation to Factor 2 or a compound of formula I or II. Alternatively, isolates of clover extracts containing is formononetin and daidzein may be fermented to produce Factor 2 or its methylated analogue for extraction with water and/or an organic solvent. As a further possibility, Factor 2 and compounds of formula I or II, may be obtained by chemical transformation of formononetin, daidzein, glycitein or other naturally-occurring isoflavones as described in more detail above.
[0083] The compounds of the formulae I or II, or Factor 2, may be administered in a manner as is generally known in the art. The dosage utilised will depend upon a number of factors including the specific application, the condition being treated, the mode of administration, the state of the subject, the route of administration and the nature of the particular compound used.
[0084] Typically, a daily dose amount of a compound of the invention, such as any of the compounds of structures (III) to (VIII) which is required in a therapeutic treatment according to the invention, is in the range of 0.1 mg to 2 g; more typically from 0.5 mg to 1 g: even more typically from 50 mg to 500 mg; most typically from 50 to 250 mg.
[0085] In the production of a pharmaceutical composition of the present invention any one or more of the compounds of formulae I or II, or Factor 2, is/are typically admixed with one or more pharmaceutically acceptable carriers, adjuvants, diluents and/or excipients as are well known in the art.
[0086] The carrier must, of course, be acceptable in the sense of being compatible with any other ingredients in the composition and must not be deleterious to the subject. The carrier or excipient may be a solid or a liquid, or both, and is preferably formulated with the compound as a unit-dose, for example, a tablet, which may contain from 0.5% to up to 100% by weight of the active compound.
[0087] Typically, one or more of the compounds of structures (III) to (VIII) may be incorporated in the compositions of the invention, which may be prepared by any of the well known techniques of pharmacy consisting essentially of admixing the components, optionally including one or more accessory ingredients.
[0088] The compositions of the invention are typically formulated to include those suitable for rectal, optical, oral, buccal, parenteral (for example, subcutaneous, intramuscular, intradermal, or intravenous) and transdermal administration, although the most suitable route in any given case will depend on the nature and severity of the condition being treated and on the nature of the particular active compound which is being used.
[0089] For parenteral administration, the compound(s) of the invention may be prepared in sterile aqueous or oleaginous solution or suspension. Suitable non-toxic parenterally acceptable diluents or solvents include water, Ringer's solution, isotonic salt solution, 1,3-butanediol, ethanol, propylene glycol or polyethylene glycols in mixtures with water. Aqueous solutions or suspensions may further comprise one or more buffering agents. Suitable buffering agents include sodium acetate, sodium citrate, sodium borate or sodium tartrate, for example.
[0090] Compositions of the invention may be prepared by means known in the art for the preparation of compositions (such as in the art of preparing veterinary and pharmaceutical compositions) including blending, grinding, homogenising, suspending, dissolving, emulsifying, dispersing and where appropriate, combining or mixing of the compound(s) of any of Formulae I or II, or Factor 2 together with the selected excipient(s), carrier(s), adjuvant(s) and/or diluent(s).
[0091] Compositions formulated as suitable for oral administration may be presented in discrete units, such as capsules, cachets, lozenges, or tablets, each containing a predetermined amount of the preferred active compound; as a solution or a suspension in an aqueous or non-aqueous liquid; as a powder or granules; or as an oil-in-water or water-in-oil emulsion. For example, compressed tablets may be prepared by compressing any one or more compounds of formulae I or II, or Factor 2, in a free-flowing form, such as a powder or granules, optionally mixed with a binder, lubricant inert diluent, and/or surface active/dispersing agent(s). Moulded tablets may be made by moulding, in a suitable machine, a powdered compound of any one of formulae I or II, or Factor 2, moistened with an inert liquid binder.
[0092] Solid forms for oral administration may contain pharmaceutically or veterinarily acceptable binders, sweeteners, disintegrating agents, diluents, flavourings, coating agents, preservatives, lubricants and/or time delay agents. Suitable binders include gum acacia, gelatin, corn starch, gum tragacanth, sodium alginate, carboxymethylcellulose or polyethylene glycol. Suitable sweeteners include sucrose, lactose, glucose, aspartame or saccharine. Suitable disintegrating agents include corn starch, methylcellulose, polyvinylpyrrolidone, xanthan gum, bentonite, alginic acid or agar. Suitable diluents include lactose, sorbitol, mannitol, dextrose, kaolin, cellulose, calcium carbonate, calcium silicate or dicalcium phosphate. Suitable flavouring agents include peppermint oil, oil of wintergreen, cherry, orange or raspberry flavouring. Suitable coating agents, include polymers or copolymers of acrylic acid and/or methacrylic acid and/or their esters, waxes, fatty alcohols, zein, shellac or gluten. Suitable preservatives include sodium benzoate, vitamin E. alpha-tocopherol, ascorbic acid, methyl paraben, propyl paraben or sodium bisulfite. Suitable lubricants include magnesium stearate, stearic acid, sodium oleate, sodium chloride or talc. Suitable time delay agents include glyceryl monostearate or glyceryl distearate.
[0093] Liquid forms for oral administration may contain, in addition to the above agents, a liquid carrier. Suitable liquid carriers include water, oils such as olive oil, peanut oil, sesame oil, sunflower oil, safflower oil, arachis oil, coconut oil, liquid paraffin, ethylene glycol, propylene glycol, polyethylene glycol, ethanol, propanol, isopropanol, glycerol, fatty alcohols, triglycerides or mixtures thereof.
[0094] Suspensions for oral administration may further comprise dispersing agents and/or suspending agents. Suitable suspending agents include sodium carboxy-methylcellulose, methylcellulose, hydroxypropylmethyl-cellulose, polyvinyl-pyrrolidone, sodium alginate or cetyl alcohol. Suitable dispersing agents include lecithin, polyoxyethylene esters of fatty acids such as stearic acid, polyoxyethylene sorbitol mono- or di-oleate, -stearate or -laurate, polyoxyethylene sorbitan mono- or di-oleate, -stearate or -laurate and the like.
[0095] The emulsions for oral administration may further comprise one or more emulsifying agents. Suitable emulsifying agents include dispersing agents as exemplified above or natural gums such as gum acacia or gum tragacanth.
[0096] For parenteral administration, the active compound(s) of Formulae I or II or Factor 2 may be prepared in sterile aqueous or oleaginous solution or suspension. Suitable non-toxic parenterally acceptable diluents or solvents include water. Ringer's solution, isotonic salt solution, 5% dextrose in water, buffered sodium or ammonium acetate solution, 1,3-butanediol, ethanol, propylene glycol or polyethylene glycols in mixtures with water. Aqueous solutions or suspensions may further comprise one or more buffering agents. Suitable buffering agents include sodium acetate, sodium citrate, sodium borate or sodium tartrate, for example. These preparations suitable for parenteral administration, are preferably administered intravenously, although administration may also be effected by means of subcutaneous, intramuscular, or intradermal injection. Aqueous solutions for parenteral administration are also suitable for administration orally or by inhalation.
[0097] Typical parenterally administered preparations may conveniently be prepared by admixing one or more of the compounds of structures (III) to (VIII) with water or a glycine buffer and rendering the resulting solution sterile and isotonic with the blood. Injectable formulations according to the invention generally contain from 0.1% to 70% w/v of active compound and are typically administered at a rate of 0.1 ml/minute/kg.
[0098] For rectal administration, the compound(s) of Formulae I or II or Factor 2 is suitably administered in the form of an enema or unit dose suppository. A suitable suppository may be prepared by mixing the active substance with a non-irritating excipient which is solid at ordinary temperatures but which will melt in the rectum. Suitable such materials are cocoa butter, waxes, fats, glycerol, gelatin and polyethylene glycols. Suitable enemas may comprise agents as exemplified above with reference to forms for topical administration.
[0099] Suitably, an inhalation spray comprising a compound(s) of Formulae I or II or Factor 2 will be in the form of a solution, suspension or emulsion as exemplified above. The inhalation spray composition may further comprise an inhalable propellant of low toxicity. Suitable propellants include carbon dioxide or nitrous oxide.
[0100] The pharmaceutical composition may contain pharmaceutically acceptable binders, diluents, disintegrating agents, preservatives, lubricants, dispersing agents, suspending agents and/or emulsifying agents as exemplified above. The veterinary composition may contain veterinarily acceptable binders, diluents, disintegrating agents, preservatives, lubricants, dispersing agents, suspending agents and/or emulsifying agents as exemplified above.
[0101] The invention includes compositions which are used for topical application which may be a cream, ointment, paste, solution, emulsion, lotion, milk, jelly, gel, spray, aerosol, oil, stick, roll-on or smooth-on, wherein the active compound comprises up to about 90%, more typically 10%, by weight of the composition, even more typically from about 0.1% to about 5% by weight, for example 3.5% by weight, even more typically from 0.5% to 2% w/w, and the compositions include topically suitable carriers, diluents, excipients, adjuvants and other additives.
[0102] Illustrative of pharmaceutically or cosmetically topically acceptable carriers or diluents are demineralized or distilled water; saline solution; vegetable based oils such as peanut oil, safflower oil, olive oil, cottonseed oil, maize oil, sesame oil, arachis oil or coconut oil; silicone oils, including polysiloxanes, such as methyl polysiloxane, phenyl polysiloxane and methylphenyl polysiloxane; volatile silicones; mineral oils such as liquid paraffin, soft paraffin or squalane; cellulose derivatives such as methyl cellulose, ethyl cellulose, carboxymethylcellulose, sodium carboxymethylcellulose or hydroxypropyl-methylcellulose; lower alkanols, for example ethanol or iso-propanol; lower aralkanols; lower polyalkylene glycols or lower alkylene glycols, for example polyethylene glycol, polypropylene glycol, ethylene glycol, propylene glycol, 1,3-butylene glycol or glycerin; fatty acid esters such as isopropyl palmitate, isopropyl myristate or ethyl oleate; polyvinylpyrrolidone; agar; carrageenan; gum tragacanth or gum acacia, and petroleum jelly. Typically, the carrier or carriers will form from 10% to 99.9% by weight of the composition.
[0103] Adjuvants typically include emollients, emulsifiers, thickening agents, preservatives, bacteriocides and buffering agents.
[0104] Emollients suitable for inclusion In a topical composition of the invention include fatty esters such as isopropyl myristate, cetyl acetate, diisopropyl adipate or C 12 -C 15 alcohol benzoates: fatty alcohols such as lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol or cerostearyl alcohol; mineral and vegetable oils such as, aloe vera and jojoba oil; lecithin: Vitamin E; lanolin; sorbitol and glycerin. Typically, the emollient or emollients will form from 10% to 99.9% by weight of the composition.
[0105] Suitable thickening agents include sodium stearate, calcium stearate, magnesium stearate, calcium palmitate and magnesium palmitate, dextran, dextrins, starch and starch products, gelatin, cellulose derivatives as exemplified above, collagen, water soluble polymers such as carboxyvinyl polymer, polyvinyl alcohol or polyvinyl acetate, pectin, xanthan gums, bentonite, hyaluronic acid, fumed silica and the like. Typically, the thickening agent or agents will form from 0.1% to 20% by weight of the composition.
[0106] Typical preservatives include ascorbic acid and its salts, erythorbic acid and its salts, ethyl and iso-propyl p-hydroxybenzoates, benzalkonium chloride, benzyl alcohol, phenyl ethanol and glydant chlorobutanol. Typically, the preservative or preservatives will form from 0.1% to 12% by weight of the composition.
[0107] Suitable buffering agents are salts of boric, acetic, phosphoric, citric, malic, silicic acids and the like, for example sodium citrate, sodium bicarbonate, sodium acetate and sodium phosphate. Additionally or alternatively, the free acids may be used, together with an alkali such as sodium hydroxide, sodium carbonate, sodium bicarbonate, potassium hydroxide, potassium carbonate or potassium bicarbonate. Typically, the buffering agent or agents will form from 0.1% to 20% by weight of the composition.
[0108] Emulsifiers may also be included in a topical composition of the invention. Illustrative nonionic emulsifiers include fatty acids such as oleic acid, stearic acid and palmitic acid: esters of lactic acid, tartaric acid, ascorbic acid or citric acid; polyalkylene glycol esters such as polyoxyethylene glycol monostearates, polyoxyethylene glycol monolaurates; polyoxyethylene glycol distearates or polyoxyethylene glycol dilaurates; polyalkylene glycol ether derivatives of aliphatic or cycloaliphatic alcohols such as polyoxyethylene nonylphenol ether, polyoxyethylene cetyl ether or polyoxyethylene stearyl ether: hexitan esters, for example sorbitan monolaurate, sorbitan monooleate, sorbitan distearate, sorbitan tristearate, sorbitan dilaurate or sorbitan trilaurate; fatty esters such as glyceryl monostearate, ethylene glycol monostearate, propylene glycol monostearate or butylene glycol monostearate; sorbitol and ethoxylated sorbitol esters of fatty acids such as polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan distearate, polyoxyethylene sorbitan dilaurate, polyoxyethylene sorbitan dioleate, polyoxyethylene sorbitan tristearate, polyoxyethylene sorbitan trilaurate or polyoxyethylene sorbitan trioleate; long-chain alcohols such as lauryl, myristyl, stearyl, oleyl, cetyl or cerostearyl alcohol; polysaccharides such as starch and starch derivative, cellulose derivatives as exemplified above, agar, tragacanth, acacia and alginic acid; and steroidal derivatives such as lanolin alcohols or ethoxylated lanolin alcohols, and beeswax. Illustrative ionic surfactants include triethanolamine and amine soaps such as triethanolamine stearate; anionic soaps such as calcium or magnesium salts of stearic acid or palmitic acid; fatty alcohol sulfates, for example sodium lauryl sulfate; alkyl or aralkyl sulfanates such as sodium sulfosuccinates or sodium dodecylbenzenesulfonate; quaternary ammonium salts containing at least one long-chain alkyl group as N-substituent, for example stearyl trimethylammonium chloride, and phosphate esters of polyalkylene glycols. Typically, the emulsifier or emulsifiers will form from 0.1% to 99% by weight of the composition.
[0109] The topical compositions of the invention may further include a sunscreen. Suitable sunscreens include opacifiers such as titanium dioxide or zinc oxide; p-aminobenzoic acid, isobutyl p-aminobenzoate, glyceryl p-aminobenzoate, or N-substituted derivatives of p-aminobenzoic acid such as isoamyl p-dimethylaminobenzoate, pentyl p-dimethylaminobenzoate, octyl p-dimethylaminobenzoate or ethyl 4-[bis(2-hydroxypropyl)amino]benzoate; 2-hydroxy-1,4-naphthoquinone; octocrylene; octyl p-methoxycinnamate or 2-ethoxyethyl p-methoxycinnamate: salicylate esters such as octyl salicylate, homomenthyl salicylate or 2-[bis(2-hydroxyethyl)-amino]ethyl salicylate; oxybenzone and methyl anthranilate. Typically, the sunscreen or sunscreens will form from 0.1% to 10% by weight of the composition.
[0110] Additionally, it will be understood that the topical compositions of the invention may include suitable colouring agents and/or perfumes well known in the art. Typical examples of suitable perfuming agents are provided in S. Arctander, “Perfume and Flavor Chemicals”, Montclair, N.J., 1969.
[0111] Formulations suitable for transdermal administration are typically presented as discrete patches adapted to remain in intimate contact with the epidermis of the recipient for a prolonged period of time. Such patches suitably contain at least one compound of formulae I or II, or Factor 2, preferably one or both of compounds A and B. as an optionally buffered aqueous solution of, for example, 0.1 M to 0.5 M concentration with respect to the said active compound. More typically, one or both of compounds A and B are present in a concentration of 0.1-0.3 M concentration.
[0112] The active compounds of formulae I or II may be provided in the form of food and/or drink compositions, such as being added to, admixed into, coated or combined with a food or drink product.
[0113] Typically, food and drink compositions of the present invention are dairy based. More typically, one or more of compounds of structures (III) to (VIII) are combined or otherwise formulated into a dairy based food or drink product such as a milk drink or supplement, and a chilled or frozen dairy product such as a dairy based dessert.
[0114] Therapeutic methods, uses and compositions may be for administration to humans or animals, including domestic animals, birds (including chickens, turkeys, ducks), livestock animals (such as cattle, sheep, pigs and goats) and the like.
[0115] It will be appreciated that the examples referred to above are illustrative only and other suitable carriers, diluents, excipients and adjuvants known to the art may be employed without departing from the spirit of the invention.
[0116] Embodiments of the invention will now be described with reference to the following non-limiting Examples.
EXAMPLE 1
[0117] 5-hydroxy-O-demethylangolensin (Compound A) [1-(2,4,5-trihydroxyphenyl)-2-(4′-hydroxyphenyl)-propan-1-one]
1. As Product of Lithium Aluminium Hydride Reduction Reaction from Glycitein
[0118] Glycitein (20.16 mg, 0.75×10 −7 mol) was weighed out and dried under vacuum. The dried glycitein was dissolved in anhydrous THF (˜3.0 ml) and to this solution 10 eq of LiAlH 4 (1.0 M in ether) was added dropwise at room temperature. The reaction was allowed to stir at room temperature overnight, then refluxed for 5 hr. After workup the solution was filtered through celite using methanol. The filtrate was concentrated and analysed by GC and HPLC (MeOH/H 2 O 40:60). Among the products separated by GC those at MU 25.69 and 28.65 were the major ones. After isolation of the two major products by preparative HPLC, these were analysed by GC-MS characterising them as derivatives of Compounds A and B respectively. Demethylation of these products was achieved by boron tribromide in dichloromethane at room temperature for three days according to Bannwart C et al., ( Finn. Chem. Lett. 1984, Vol 11, p 120). In performing the GC-MS, a 30 metre SE30 capillary column was used with temperature program of 200-230° C. at increments of 2° C./min, and 230-280° C. at increments of 10° C./min. The carrier gas was helium.
2. As a Product of Acylation Reaction
[0119] Step 1: Formation of 2,4,5,4′-tetramethoxy-α-methyldesoxybenzoin. To a mixture of 2-(p-methoxyphenyl)propionic acid (0.20 g, 1.11 mmol) and polyphosphoric acid (5 gm), 1,3,4-trimethoxy benzene (0.186 g, 1.11 mmol, 0.166 ml) was added. The mixture was allowed to heat to 75° C. while stirring for 6 hours. TLC (30% EtOAc:Hexane) and gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) analyses confirmed the presence of two major products with MU values of 24.68 and 25.01 (ratio 1:4), Chromatography on silica column (30% EtOAc:Hexane) allowed the isolation of the two products. Product MU 24.92 was isolated as a crystalline low melting solid. NMR data and GC-MS data confirmed the above structure. A 42% and 11% yield was obtained for products MU 25.01 and MU 24.68 respectively.
[0120] Step 2: Formation of 2,4,5,4′-tetrahydroxy-α-methyldesoxybenzoin. The product 2,4,5,4′-tetramethoxy-α-methyldesoxybenzoin (MU 25.01; 0.063 g) obtained from Step 1 above was dissolved in anhydrous dichloromethane (30.0 mL) and boron tribromide (0.271 g, 1.08 mmol) was added to the solution. The mixture was allowed to stir at room temperature for 24 hours under nitrogen. TLC (30% EtOAc:hexane) established the presence of a single product which on GC analysis as the trimethylsilyl ether gave a single peak at MU 26.01. After workup with ice/water the product was extracted with diethyl ether, washed with water, dried and concentrated to give a crude yellow oil, which by NMR and GC-MS data was confirmed to be 2,4,5,4′-tetrahydroxy-α-methyldesoxybenzoin.
[0121] Mass Spectra Data (EIMS: electron ionisation; CIMS; Chemical ionisation; High resolution; HR)
[0122] HR: 274.084267, theoretical 274.084267.
[0123] EIMS: m/z (% rel int) 274 [M]+ (14), 153(100); 121(29), 77(8).
[0124] EIMS as the tetra-trimethylsilyl derivative: 562(1.6): 547(4.7); 457(1.6): 369(100); 281(6.7); 193(5.4); 147(2.7).
[0125] CIMS as the tetra-trimethylsilyl derivative: M+b 1 = 563 (75); 547(59): 491(15); 370(31); 369(100); 193(22).
[0126] NMR Data
[0127] 1 H n.m.r.
[0128] (Acetone-d6, 2.05 ppm) δ 1.39 (3H, d, J=7.2 Hz, CH 3 ), 4.62 (1H, q, J=7.2 Hz, CH), 6.29 (1H, s, ArH-3), 6.75 (2H, d, J=9.2 Hz, ArH-3′,5′), 7.17 (2H, d, J=9.2 Hz, ArH-2′,6′), 7.33 (1H, s, Ar-6) 8.73
[0129] 13 C n.m.r.
[0130] (Acetone-d6, ppm) 1873, 45.59, 103.05, 110.845, 115.38, 115.58, 128.51, 132.96, 137.60, 153.86, 156.25, 159.85, 204.77.
[0131] UV: λ max =283 nm
EXAMPLE 2
[0132]
[0133] 5 -deoxydihydroglycitein (Compound B)
[0134] Compound B was obtained in a series of reactions as illustrated in Scheme 7, involving an acylation reaction, formation of an α-alkenyl ketone and cyclisation/demethylation. In brief, 2,4,5-trimethoxyphenyl-4′-methoxybenzyl ketone was obtained as an intermediate in an acylation reaction using 1,2,4-trimethoxybenzene (5.9 mmol), 4-methoxyphenylacetic acid (5.9 mmol) and polyphosphoric acid (17 gm) after beating at 70° C. for one hour with mechanical stirring. Potassium carbonate was then added to the reaction for another one and half hours. The crude product was purified by recrystallization from ethyl acetate and light petroleum to give light yellow crystals (75% yield). The α-alkenyl ketone was subsequently obtained by a modification of Gandhidasan's method (Gandhidasan R et al., Synthesis, 1982, 1110). In brief, to a suspension of 2,4,5-trimethoxyphenyl-4′-methoxybenzyl ketone in ethanol, paraformaldehyde and N,N-dimethylamine was added and the mixture was allowed to reflux while heated for one hour. When the reaction was complete, the precipitate was filtered and the filtrate was concentrated in vacuo, after which the residue was dissolved in ethyl acetate and washed with water. The organic layer was dried with magnesium sulphate and filtered, and the solvent was removed to give the crude product. On purification by flash chromatography two compounds were obtained in 57% yield. Fractional recrystallization of the mixture gave 1-(4-methoxyphenyl)-1-(2,4,5-trimethoxybenzoyl)ethylene as the major product (˜41%) and α-ethoxymethyl-2,4,5-trimethoxyphenyl-4′-methoxybenzyl ketone as the minor product (˜17%). The method provided the best yields when 1% potassium bicarbonate is used instead of the dimethylamine in the methylation step.
[0135] When sodium hydroxide was used instead the percentage yield was lower namely 38% and 14% respectively for these two products. The desired dihydro product Compound B (6,7,4′-trihydroxyisoflavone) was finally obtained by demethylation of 1-(4-methoxyphenyl)-1-(2,4,5-trimethoxybenzoyl)ethylene using boron tribromide in dichloromethane at room temperature for three days according to Bannwart C et al., Finn. Chem. Lett. 11 120 (1984) followed by cyclisation of the resulting brominated intermediate by sodium acetate in methanol.
[0136] In the formation of the α-alkenyl ketone in the absence of a base the reaction will not proceed and the starting material will remain unchanged. The good yield of this method provides a good chemical method for the synthesis of a number of the dihydro derivatives of daidzein, genistein or glycitein.
[0137] Mass Spectra Data (EIMS electron ionisation; CIMS Chemical ionization; High resolution HR)
[0138] Compound B: HR: 272.0673 theoretical 272.0673
[0139] EIMS: m/z (% rel. int) 272 [M]+ (31), 244(9); 168(7); 153(100); 120(40); 107(27); 91(11).
[0140] CIMS: 301 M+29(14); 273 M+1(52); 257(37); 137(23); 97(17); 83(45); 71(100).
[0141] EIMS as the tri-trimethylsilyl derivative: MU 28.48, MW 488; 488(14); 473(7); 369(30); 296(100); 281(9); 192(27); 177(24); 147(9).
[0142] NMR Data
[0143] 1 H n.m.r. (Acetone-d6) δ 2.05 ppm (1H, dd, J 3.2eq =5.0 Hz, J 3.2ax =9.5 Hz, H-3), 4.14 (1H, dd, J 2ax,2eq =9.7 Hz, J J 2ax,3 =9.6 Hz, H 2ax ), 4.99 (1H, dd, J 2eq,2ax =9.8 Hz, J 2eq,3=4.9 Hz, H 2eq ), 6.38 (1H, s, ArH-8), 6.82 (2H, d, J=8.6 Hz, ArH-3′,5′), 7.27 (2H, d, J=8.6 Hz, ArH-2′,6′), 7.46 (1H, s, ArH-5).
[0144] 13 C n.m.r. (Acetone-d6, 29.8 ppm) δ 33.5, 54.6, 103.9, 111.9, 116.6, 128.4, 129.3, 138.78, 155.2, 158.0, 160.4, 201.8.
[0145] UV: λ max =284 nm
EXAMPLE 3
[0146] 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-2-propene (3′-hydroxy-O-demethyldehydroangolesin); Structure (VI)
1. 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-ethane
[0147] A mixture of 1,3-dimethoxybenzene (2.00 g, 14.47 mmol) and 3,4-diemethoxyphenylacetic acid (2.84 g, 14.47 mmol) in polyphosphoric acid was heated at 80° C. for 2 hours. After cooling, the mixture was poured onto ice water and the water was extracted with ethyl acetate (50 mL). The combined organic phases were washed with water, sodium bicarbonate solution and water and dried over anhydrous magnesium sulfate. Evaporation of the solvent gave light yellow crystals of 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-ethane which were purified by recrystallisation.
[0000] 2. 1-(2,4-dimethoxyphenyl)-2-(3′,4′-dimethoxyphenyl)-1-oxo-2-propene and 1-(2,4-dimethoxyphenyl)-2-(3′,4′-dimethoxyphenyl)-1-oxo-3-ethoxy-propane
[0148] A mixture of the product of step 1 (3.504 g, 11.08 mmol), 95% paraformaldehyde (1.275 g, 46.66 mmol) and N,N-dimethylamine (5.6 mL, 46.66 mmol) in ethanol (58 mL) was heated under reflux for one hour. Then potassium carbonate (1.612 g, 11.67 mmol) was added to the mixture and heating under reflux was continued for a further three hours after which the precipitate was removed by filtration and the solvent was removed under reduced pressure. The residue was dissolve in ethyl acetate and the solution was washed with water. 0.2 M HCl and water, dried over magnesium sulfate and concentrated to give a yellow oil. 1-(2,4-dimethoxyphenyl)-2-(3′,4′-dimethoxyphenyl)-1-oxo-2-propene was separated from 1-(2,4-dimethoxyphenyl)-2-(3′,4′-dimethoxyphenyl)-1-oxo-3-ethoxy-propane by column chromatography with a mobile phase of 40% ethyl acetate in hexane.
[0000] 3. 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-2-propene
[0149] 0.406 g (1.08 mmol) of 1-(2,4-dimethoxyphenyl)-2-(3′,4′-dimethoxyphenyl)-1-oxo-3-ethoxy-propane were reacted with boron tribromide (10.84 mmol) in 22 mL dichloromethane for three days by the method of Bannwart C. et al., Finn. Chem. Lett. 11 120 (1984). Workup and chromatography of the reaction product afforded 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-2-propene as the minor product and 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-3-bromo-propane as the major product.
[0150] Mass spectral data (electron impact) for 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-2-propene as tetra-TMS derivative: m/z (% relative intensity) at 209(10), 267(4.5), 281(100), 545(20), 560(23).
EXAMPLE 4
[0151] 7-hydroxy-(3′,4′-dihydroxyphenyl)-2,3-dihydroisoflavone (3′-hydroxy-dihydro-daidzein); Structure (VII)
[0152] 0.157 g of 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-3-bromo-propane, the major product of step 3 in Example 3, and about 2 molar equivalents of sodium acetate ware mixed with 88 mL of methanol and heated at about 60° C. for 4 hours. After cooling, the mixture was acidified to pH 5 and the methanol was removed under reduced pressure. The residue was dissolved in ethyl acetate (50 mL) and the solution was washed with water and concentrated. The crude product was separated by column chromatography to yield approximately equal amounts of 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-2-propene and 7-hydroxy-(3′,4′-dihydroxyphenyl)-2,3-dihydroisoflavone.
[0153] Mass spectral data (electron impact) for 7-hydroxy-(3′,4′-dihydroxyphenyl)-2,3-dihydroisoflavone as tri-TMS derivative: m/z (% relative intensity) at 192(7.2), 281(100), 473(6.6), 488(17).
EXAMPLE 5
[0154] 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxopropane; Structure (V)
[0155] The title compound was obtained by catalytic hydrogenation of 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-2-propene obtained as in Example 3 or Example 4. To a solution of 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxo-2-propene in methanol was added palladium on carbon, and hydrogen gas was bubbled vigorously through the solution for ten minutes. Removal of the catalyst and evaporation of the solvent afforded the title compound.
[0156] Mass spectral data (electron impact) for 1-(2,4-dihydroxyphenyl)-2-(3′,4′-dihydroxyphenyl)-1-oxopropane as tetra-TMS derivative: m/z (% relative intensity) at 209(5.8), 281(100), 369(2.4), 457(1.2), 459(1.3), 547(4.0), 562(1.2).
EXAMPLE 6
[0157] 1-(2,4,5-trihydroxyphenyl)-2-(4-hydroxyphenyl)-1-oxo-2-propene (5-hydroxy-2-dehydro-O-Dma); Structure (VIII)
[0158] This compound was prepared as shown in Scheme 7 utilising methodology analogous to dial described in Example 3.
[0159] Mass spectral data (electron impact) for 1-(2,4,5-trihydroxyphenyl)-2-(4-hydroxyphenyl)-1-oxo-2-propene as tetra-TMS derivative: m/z (% relative intensity) at 147(40), 281(28), 369(63), 370(20), 545(94), 546(46), 560(100), 561(50), 562(27).
EXAMPLE 7
Bacterial sp and Culture Conditions:
[0160] The standard incubation assays of bacteria (100 mg wet wt) with isoflavone substrates (5×10 −5 M), the composition of the mineral salt medium and the isolation of the transformation products from the medium were essentially as described according to Klus,
[0161] 25 K. et al., Arch. Microbiol. 164 428-434 (1995). The mineral medium and micronutrients were used according to Pfennig and Lippert (1966). In summary Bacterial sp were cultivated on Merck Standard I nutrient agar and for incubation experiments for 15 hr in 100 ml Merck Standard I nutrient broth. Prior to incubation the bacteria were washed twice with 200 ml Kpi buffer (0.05 M, pH 7.5). After centrifugation (10,000 g, 15 min) 100 mg bacteria (fr. Wt) were inoculated in 5 ml mineral medium and 50 μl substrate solution (DMSO-MeOH, 1:10) was applied to the bacterial culture. Substrate concentration was 5×10 −5 . The cultures were incubated in culture tubes (200×16 mm) in an orbital shaker at 200 rpm. 30° C.
EXAMPLE 8
Effects of Isoflavonoid Phytoestrogens on the Induced Growth of MCF-7 Cells and Other Cells.
[0162] Compound A was compared with genistein to test the cell viability of MCF-7 cells. Genistein was known, prior to this invention, to be the most potent individual inhibitor of cancer ceils in in vitro experiments. The cell viability was tested using the MTS in vitro cytotoxicity assay. This is considered the most convenient assay because of its ease of use, accuracy and rapid indication of toxicity (Malich G et al., Toxicology 124(3): 179-92 (1997).
[0163] The results obtained show that at high concentrations (40 micrograms/ml) of each. genistein showed an inhibition at 1, 2, 3 and 6 days of incubation with an IC50 of 32, 22, 15 and 18 micrograms/ml, compared with IC50 values of 6, 6.5 and 7 for Compound A for the same periods respectively. More importantly, Compound A inhibited the growth of MCF-7 cells even at low concentrations, namely 2.5 micrograms/ml and as early as within 8 hours of incubation and at days 1 and 2. By contrast, other isoflavonoids including genistein at concentrations (<10 μM) enhance rather than inhibit the growth of MCF-7 cancer cells.
[0164] IC50 values observed for other compounds of the invention against MCF-7 cells were as follows:
[0000]
Compound of structure:
IC50 (μg/mL)
(IV)
6-10
(V)
10-20
(VI)
3.2
(VII)
about 28
(VIII)
<8
[0165] The compound of structure (VI) was also tested against PC3 and LNCap cells and the IC50 values observed were 6.2 and 7.0 μg/mL respectively.
EXAMPLE 9
Comparative Inhibitory and Proliferative Effects of Daidzein and Genistein, Their Methylated Analogues and Metabolites with 5-hydroxy-O-Dma (Compound A) on MCF7 Cells
[0166] In vitro cell tissue culture experiments with MCF7 breast cancer cells when incubated with 5-hydroxy-O-Dma (Compound A) showed significant inhibition as compared with genistein, daidzein or their methylated precursors, namely formononetin and biochanin A or their metabolites for concentrations of 15-40 μg/ml. This variation was more significant when cells were incubated for 8 hours where it was demonstrated that 5-hydroxy-O-Dma had an IC50 of 6 μg/ml as compared with that of genistein which had an IC50 of >40 μg/ml for the same period of incubation. Subsequent incubations at 24 hours, 48 hours, 72hours and 144 hours revealed that the IC50 value of 5-hydroxy-O-Dma remained basically unchanged: ie remained in the range of 4-7 μg/ml. This is in contrast to the IC50 values obtained for genistein after incubations for 48 hours (IC50=38) and 144 hours(IC50-15 μg/ml).
[0167] For concentrations of less than or equal to 10 μM of 5-hydroxy-O-Dma and genistein, no significant inhibition was observed. However, in the case of genistein, some proliferative activity of cancer cells was demonstrated at concentrations of less than or equal to 10 μM, whereas 5-hydroxy-O-Dma showed no proliferative activity of cancer cells.
[0168] When daidzein, formononetin, biochanin A and other metabolites of daidzein and genistein such as dihydrodaidzein, tetrahydrodaidzein (transisomer). O-Dma, 6-hydroxy-O-Dma and equol were tested for their inhibitory effect on MCF7 cells, it was found that with the exception of biochanin A and 6-hydroxy-O-Dma which showed some inhibition with an IC50 of 18-23 μg/ml at 72 and 144 hours incubation, all other metabolites had no significant effect, with their IC50 values at about 36->50 μg/ml.
[0169] These results suggest that compound A is a potent inhibitor of breast cancer cells but more importantly, compound A showed no proliferative activity of cancer cells at low concentrations as genistein docs. The 6,7-dihydroxy groups in compounds of the invention appear to be critical for this difference of biological activity of compounds of the invention when compared with analogues such as O-Dma and 6-hydroxy-O-Dma.
EXAMPLE 10
Comparative Inhibitory Effects of Daidzein and Genistein, Their Methylated Analogues and Metabolites with 5-hydroxy-O-Dma (Compound A) on Breast Cancer Cells
[0170] 5-Hydroxy-O-Dma when tested with MDA-MB-468 (estrogen negative) cancer cells showed significant inhibition at day 6 (IC50=6.8 μg/ml) as compared with 8.8 μg/ml for genistein and 3-7 times more inhibitive when compared with analogues of daidzein and genistein namely O-Dma (20 μg/ml) and 6-hydroxy-O-Dma (43 μg/ml) respectively. The IC50 of 5-hydroxy-O-Dma using MCF-7 estrogen positive breast cancer cells on day 6 of incubation was 2.1 μg/ml for 5-hydroxy-O-Dma as compared with the analogues of daidzein and genistein namely O-Dma (38 μg/ml) and 6-hydroxy-O-Dma (33 μg/ml) respectively.
[0171] These results suggest that inhibition of 5-hydroxy-O-Dma like that of genistein, was more severe for the estrogen negative (−ve) cancer than that of the estrogen positive (+ve) cancer cells which suggests that in both these cases the mechanism of action is not related to the estrogen receptors.
EXAMPLE 11
Inhibitory Effects of Factor-2 on Breast Cancer Cells
[0172] Factor 2 was obtained by complete demethylation of glycitein after 4 days of incubation with BBr 3 . Incomplete demethylation gave a mixture of glycitein and Factor 2. Alternatively, following fermentation of daidzein and glycitein from clover to give Factor-2, selective extraction and/or precipitation of Factor 2 from the fermentation medium can be easily achieved.
[0173] Factor-2 when tested with MCF 7 estrogen positive breast cancer cells and MDA-MB-468 (estrogen negative) breast cancer cells showed significant inhibition of both types of cancer cells. Inhibition of MCF-7 cells using Factor 2 gave IC50 values (at day 6 of incubation) of 12 μg/ml and for MDA-MB-468 cells, the IC50 value was 8 10 μg/ml.
[0174] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications which fall within its spirit and scope. The invention also includes all of the steps, features. compositions and compounds referred to or indicated in this specification, individually or collectively, and any and all combinations of any two or more of said steps or features. | There are disclosed compounds of formulae (I) or (II) in which A is selected from the group consisting of (1), (2), (3) and (4); OH, and one of R 1 and R 2 is selected from H, OH and OCH 3 , and the other of R 1 and R 2 is selected from OH and OCH 3 ; one of R3 and R4 is selected from H, OH and OCH3, and the other of R3 and R4 is selected from OH and OCH3; provided that at least one of the pairs R 1 , R 2 and R 3 , R 4 are both OH; R 5 is selected from OH and OCH 3 ; and
denotes a single or double bond; and pharmaceutically acceptable salts and prodrugs thereof. The compounds of the invention are useful for the treatment of hormone-dependent conditions and cancers. | 0 |
TECHNICAL FIELD
[0001] The invention relates to a needle that delivers electrical current and more particularly to a needle that delivers high frequency electrical current in the vicinity of a neural structure.
BACKGROUND OF THE ART
[0002] A minimally invasive technique of delivering high frequency electrical current has shown to relieve localized pain in many patients. The high frequency electrical current is typically delivered from a generator via connected electrodes that are placed in a patient's body. The needles include an insulated shaft with an exposed electrically conductive tip. Tissue resistance to the high frequency electrical current at the tip causes heating of adjacent tissue. When temperature increases sufficiently tissue coagulates. The temperature that is sufficient to coagulate unmyelinated nerve structures is 45° C., at which point a lesion is formed and pain signals are blocked. This results in relief from pain.
[0003] Needles with varying geometries are used in such applications. For example, the exposed tip of the needle can be pointed, blunt and rounded or open, varying in shape in accordance with the needs of different procedures. Pointed tips are self-penetrating while rounded tips are useful in soft tissue areas such as the brain where it is critical not to damage nerves. However, blunt needles can do more tissue damage than small diameter sharp needles. Open tips can be used to deliver a therapeutic agent during electrical treatment. U.S. Pat. No. 6,146,380 to Racz et al. describes electrical needles with curved tips used in high frequency lesioning.
[0004] This technique of relieving back pain has also been used with needles penetrating the intervertebral disk. U.S. Pat. Nos. 5,433,739 and 5,571,147 to Sluijter et al. and WIPO publication WO 01/45579 to Finch et al. describe needles that are used in the intervertebral disk to relieve back pain caused by herniated disks.
[0005] For treatment, the needle having a hollow shaft and a removable stylet therein is inserted into the patient's body and positioned. Once the needle is positioned, the stylet is withdrawn and a distal end of a high frequency probe is inserted until the distal end of the probe is at least flush with the distal end of the shaft, (i.e. the exposed tip). The probe is connected to an external signal generator that generates high frequency electrical current.
[0006] These needles are often used to denervate certain portions of a spine of the patient. Accurate placement of the needle in a complicated structure like the spine requires great technical skill by a treating clinician. In these procedures, the needle is viewed via X-ray or a fluoroscope to assist placement and is guided into the body. One limitation of the technique used currently is that the insulated shaft is not distinguishable from the exposed tip of the needle under X-ray or fluoroscopy. Therefore, accurate visualization of the exposed tip is not possible.
[0007] Prior art devices for accurate placement have not been used in conjunction with radio frequency needles. Radiopaque marking has been used to accomplish precise placement of catheters and stents. U.S. Pat. No. 5,429,597 to Demello et al. discloses a balloon catheter having a radiopaque distal tip composed of a polymer mixed with a radiopaque powder such as tungsten. U.S. Pat. No. 6,315,790 to Gerberding et al. describes a catheter constructed with radiopaque polymer hubs where the hubs provided the dual function of stent crimping and marker bands.
[0008] An example of a catheter utilizing an external marker band is described in U.S. Pat. No. 5,759,174 to Fischell et al. The catheter has a single external metal marker band to identify the central portion of the stenosis once the delivery catheter is removed.
[0009] In spite of the improved illumination of the aforementioned devices when marked, there are some limitations to their application. Upon attachment conventional radiopaque markers may project from the surface of the catheter or stent, thereby causing a departure from its ideal profile. Some markers add rigidity to the stent and catheter in areas that had been designated for deformation. A needle for delivering radio frequency that overcomes some or all of the limitations of the prior art is desired.
SUMMARY OF THE INVENTION
[0010] The present invention provides for improved placement of a needle delivering high frequency energy by incorporating radiopaque markers to distinguish the exposed tip from the shaft under fluoroscopic visualization.
[0011] To facilitate precise placement of the exposed tip, the tip is distinguishable from the rest of the needle when viewed under X-rays and fluoroscopy. When a needle with radiopaque marking, according to the present invention, is inserted in the patient's body, the location of a lesion made or to be made by the needle can be easily determined, as the tip of the needle can be distinguished from the electrically insulated shaft.
[0012] The present invention provides a needle for insertion into a patient's body comprising an electrically insulated shaft having an electrically conductive tip portion and a radiopaque marker associated with at least one of the shaft and the tip portion.
[0013] The tip portion of the needle is the exposed tip and can be of varying dimensions. The radiopaque marker distinguishes the electrically insulated portion of the needle from the tip portion. This effectively identifies the position of the needle when in the body. The marker may be adapted to needles having various geometric shapes. The insulated portion of the needle may include an insulating coating. The coating may cover the radiopaque marker on the needle preventing a departure from the needle's true profile.
[0014] The radiopaque marker can comprise bands or radiopaque coatings of metals/polymers, or radiopaque materials deposited on the surface of the needle by techniques such as ion implantation or vapor deposition. These features and others will be apparent in the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order that the invention may be readily understood, embodiments of the invention are illustrated by way of examples in the accompanying drawings, in which:
[0016] [0016]FIG. 1 is a schematic illustration of a needle connected to a high frequency generator, in accordance with the present invention;
[0017] [0017]FIG. 2 is a side elevation view of an embodiment of the needle of the present invention, including a stylet;
[0018] FIGS. 3 to 7 illustrate side elevation views of different embodiments of the needle in accordance with the present invention, with radiopaque marking; and
[0019] [0019]FIG. 8 illustrates a stylet according to the present invention including radiopaque marking.
DETAILED DESCRIPTION OF THE INVENTION
[0020] In accordance with an aspect of the invention a medical apparatus is provided for delivering high frequency electrical current to neural structures. As illustrated in FIG. 1, the medical apparatus comprises a generator 100 for producing high frequency electrical current, a needle 102 with an electrical probe 110 connected to the generator 100 that is placed in the needle 102 for delivering the high frequency electrical current and a reference electrode 101 that completes the circuit. The needle 102 with the probe 110 is placed in a portion of a patient's body indicated generally at 106 .
[0021] As can be seen more clearly in FIG. 2, the hollow shaft of the needle 102 is covered with an insulating coating 103 leaving a portion of the tip 104 uncoated, exposed and electrically conductive. The tip 104 may have a sharpened end that will assist with penetration of the tip 104 into the tissue of the body 106 during percutaneous entry. The exposed tip 104 represents the active electrode area. The reference electrode 101 typically has a much larger area than the exposed tip 104 so that there is no heating at the surface of the body 106 where the reference electrode 101 is attached. The passage of high frequency electrical current through the needle 102 produces a lesion 105 in the region of the exposed tip 104 . The lesion 105 causes coagulation of the neural structures in that region and is responsible for pain relief. It is therefore important to know the position of the exposed tip 104 to gauge the relative position and region that will be affected by the high frequency electrical current.
[0022] As stated above, FIG. 2 depicts the needle 102 having a hollow shaft typically of one or more metals and a hub 201 . Preferably the hub 201 is a Luer lock type molded to the shaft; however, other methods of attachment may be used as will be understood by a person skilled in the art. Insulated in needle 102 through the hollow shaft is an elongate stylet 205 shown in dotted outline. The stylet 205 is adapted to assist in piercing the skin and tissue for entry to a treatment area. The stylet 205 comprises a cap 200 cooperating with Luer lock hub 201 . The hub 201 is also operable to accommodate an electrical probe 110 that is inserted into the shaft of the needle 102 when the stylet 205 is removed. A portion of the shaft is covered with an electrically insulating coating 103 leaving the tip 104 exposed. The end-point of the insulating coating 103 on the needle 102 is indicated at numeral 204 . In use, the needle 102 with the stylet 205 is inserted into the body 106 . Once a correct position has been attained the stylet 205 is removed and the electrical probe 110 that delivers the high frequency electrical current is inserted through the needle 102 .
[0023] The needle 102 with the stylet 205 is inserted into the patient's body 106 under X-ray/fluoroscopic guidance. One common method for inserting the needle 102 is to locate an X-ray source along one or more desired axes. An image detector on the opposite side of the body portion 106 where the needle 102 is inserted receives the X-rays, thereby permitting verification of the proper location and orientation of the tip 104 . Radiopaque marking on the needle 102 or stylet 205 will enable its better visualization in this process. A radiopaque marker could be applied on selected portions of the needle 102 by, for example, use of masks. Advantageously selected patterns of radiopacity will allow the precise orientation to be discerned by inspection of the fluoroscopic image. FIGS. 3 to 8 illustrate different exemplary embodiments of patterns of radiopacity that can be adopted in this invention. It will be understood by persons skilled in the art that other shapes and patterns may be adopted.
[0024] In the embodiment illustrated in FIG. 3 a radiopaque band 300 is located at the edge 204 of the coating and thereby aids in distinguishing between the coated region 103 and uncoated region 104 . The radiopaque band 300 may be located before the coating end-point 204 or just after the coating end point 204 . It may run 360° around the shaft or be applied through a certain distance of the circumference, for example through 180° or 90°. FIG. 3 illustrates one embodiment that includes a radiopaque band 300 through 180° of the shaft, on the side of the beveled tip, just before the coating end-point 204 . This provides a clear demarcation between the coated 103 and exposed regions 104 of the needle 102 .
[0025] The band 300 can be applied in a number of ways including techniques such as, but not limited to, vapor deposition, ion implantation, dip coating, metal plating and electro plating. Bands of radiopaque materials such as platinum iridium bands can also be fused onto the needle 102 .
[0026] An alternate embodiment of the invention is depicted in FIG. 4. A radiopaque marker 400 may be placed on the needle 102 to distinguish between the coated metal shaft 103 and the exposed metal tip 104 and may be a variety of shapes and sizes. The shape of the marker 400 may also be used to indicate the direction of the beveled tip.
[0027] [0027]FIG. 5 illustrates another embodiment of the invention. The entire exposed part 104 of the needle 102 , is radiopaque indicated at numeral 500 and can be discerned better when viewed under a fluoroscope. The coated region of the needle 103 can be masked and the exposed tip 104 coated with a radiopaque material. Techniques such as vapor deposition and ion bombardment can be used to achieve such coating.
[0028] An alternate embodiment of this invention can be obtained by imparting radiopacity to the insulating coating 600 as illustrated in FIG. 6. The insulating coating on the needle can be made radiopaque in a number of ways such as vapor deposition, ion-bombardment and ion-implantation. This renders the entire insulated portion of the needle radiopaque.
[0029] [0029]FIG. 7 illustrates the needle 102 with two radiopaque bands 700 at the coating end-point 204 and the edge of the exposed tip 104 . This defines the region of the exposed tip 104 where delivery of high frequency electrical current to the tissue 106 occurs.
[0030] [0030]FIG. 8 illustrates the stylet 205 with radiopaque marking 800 , which may include any of the embodiments described in FIGS. 3-7 above. The stylet 205 and needle 102 are inserted into the patient's body 106 to ensure correct placement. The radiopacity on the stylet 205 will serve to identify the exposed tip 104 on the needle 102 .
[0031] An example of suitable material that may be used to impart the desired radiopacity is radiopaque ink with tungsten that is pad printed. The material is selected based on its radiopacity. Other suitable materials include, but are not limited to, high-density metals such as platinum, iridium, gold, silver, tantalum or their alloys, or radiopaque polymeric compounds. Such materials are highly visible under fluoroscopic illumination and are therefore visible even at minimal thickness.
[0032] The embodiments of the invention described above are intended to be exemplary only. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims. | A method and apparatus are disclosed for improving accuracy of placement of needles during delivery of high frequency signals near a neural structure to form lesions. The apparatus includes a needle that can deliver electrical current where a portion of the needle is electrically insulated and a portion of the needle is exposed and electrically active, thereby causing lesions. The needle includes radiopaque marking to differentiate the electrically insulated region from the exposed region, allowing it to be better discerned in the body under fluoroscopy. | 0 |
The present invention relates to apparatus for locking a nut assembly on an externally threaded spindle of a vehicle axle.
BACKGROUND OF THE INVENTION
It is common practice to stress an externally threaded shank portion of a bolt member by applying torque to the nut to advance the threaded portion of the nut along the threaded shank portion so that the shank portion of the bolt is placed under a desired or predetermined stress. The stress imparted to the shank portion of the bolt can be determined by using a torque reading wrench to measure the torque applied to the nut or by using other means to measure the applied force by a spanner wrench. Obviously, the torque may be applied to a nut or the head portion of a bolt in a usual nut/bolt fastener arrangement. In order to secure wheels to associated axle spindles, it is known to use a double nut arrangement wherein one nut is tightened against the other nut to be locked. In such locking arrangements, the locking nut must be tightened forcefully against the main nut. Thus, it is difficult to determine the exact position of the main nut on the threaded axle spindle. Therefore, it is difficult to be certain that the main nut is tightened within predetermined torque range.
Also, it is known to employ a plurality of jack bolts threadably engaged within openings in a flange on a fastener to stress a shank part of the fastener. The flange may be a collar retained on a shaft by a retainer, a nut on a threaded end of a bolt, or the head portion of a bolt. The jack bolts can be arranged in the flange on an end of a shaft. When the flange is in the form of a ring, for example, a retainer such as a split ring, a snap ring, or interlocking fastener may be used to secure the flange to the shank. The magnitude of the compressive force on each jack bolt is only a fraction of the stress imparted to the shank portion of the fastener. A nut member or head portion of a standard nut and bolt assembly, provides sufficient space for threaded engagement of bolt to stress the shank part of the bolt to a magnitude that will at least equal the strength of the bolt shank.
These designs have a complex construction and are complicated and expensive to manufacture.
SUMMARY OF THE INVENTION
It is an object of present inventions to produce a lock nut assembly which is relatively simple in design, can be economically manufactured, and will produce to necessary locking function desired.
According to one embodiment of the invention, the above as well as other objectives and advantages may be achieved, there is provided a lock nut assembly adapted to be locked on an externally threaded shank having a longitudinal axis comprising at least a pair of coaxially oriented annular nut members having threads formed on the inner peripheral surfaces complimenting and cooperating with the externally threaded shank; spaced apart boss means extending from at least one of the facing surfaces of the nut members toward the facing surface of the other nut member; threaded shank means extending from the facing surface of at least one of the nut members, the shank means extending in a direction parallel to the longitudinal axis of the externally threaded shaft; aperture means in the other of the nut members for receiving the threaded shank means; and nut means receivable on the threaded shank means for tightening the nut members to effect a jamming action between the threads formed on the inner peripheral surfaces of the nut members and the externally threaded shank to restrict relative rotational movement there between.
BRIEF DESCRIPTION OF THE DRAWINGS
The above as well as other objects and advantages of the invention will become readily apparent to one skilled in the art by reading the following detailed description of the preferred embodiments of the invention, when considered in the light of the accompanying drawings, in which:
FIG. 1 is an exploded view of a locking nut assembly in accordance with the present invention;
FIG. 2 is an enlarged sectional view of the assembly illustrated in FIG. 1 in a operative position; and
FIG. 3 is a view similar to FIG. 2 illustrating an alternative embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, there is illustrated in FIG. 1 and 2 a lock nut assembly embodying the features of the present invention. An annular nut member 10 is illustrated. The nut member 10 is provided with threads 12 formed on the inner peripheral surface. The threads 12 are formed to compliment and cooperate with the externally threaded shank 14 illustrated in dotted lines in FIG. 2.
A boss 16 is formed by staking the material used to form the nut member 10. The boss 16 extends outwardly from a surface of the body of the nut member 10. Since the boss 16 is formed by a staking operation, a cavity 18 is formed on the opposing surface of the nut member 10.
A pair of diametrically opposed externally threaded shanks 20, 22 are formed integral with and are adopted to extend outwardly from the same surface of the nut member 10 as the boss 16. The shanks 20, 22 extend in parallel relation to one another and to the longitudinal axis of the externally threaded shaft 14 to which the nut member 10 is to be fitted.
A second nut member 24 is provided with threads 26 formed on the inner peripheral surface. The threads 26 are formed to compliment and cooperate with the externally threaded shank 14 illustrated in dotted lines in FIG. 2.
A boss 28 is formed by staking the material used to form the nut member 24. The boss 28 extends outwardly from a surface of the body of the nut member 24. The surface from which the boss 28 extends is in facing relation to the surface of the nut member 10 from which the boss 16 is adapted to extend. Since the boss 28 is formed by a staking operation, a cavity 30 is formed to extend inwardly from the opposing surface of the nut member 24.
A pair of diametrically opposed apertures 32, 34 are formed in the nut member 24. The apertures 32, 34 are provided to readily receive the externally threaded shanks 20, 22, respectively.
In the assembled form, the locking nut assembly is maintained in an assembled unitary condition by nuts 36, 38 and cooperating respective lock washers 40, 42. When the nuts 36, 38 are tightened, the bosses 16, 28 are caused to physically contact the opposing facing surface of the opposing nut member 24, 10, respectively. The threads 26 are formed such that they will satisfactorily engage with the threads engaged by the threads 12 of the nut member 10.
The application of the lock nut assembly of the invention is accomplished by initially causing the annular nut member 10 to be received on the externally threaded shaft 14 and rotated onto the threads of the shaft 14. As the nut member 10 is rotated and moved axially of the shaft 14, the threads 26 of the second nut member 24 become threadably engaged on the threads of the shaft It will be understood that engagement of the threads 26 of the second nut member 24 is facilitated due to the floatable relation between the nut members 10 and 24. The nut member 10 is then tightened, preferably by a torque wrench until the desired torque is reached. Next, the nuts 36, 38 are tightened sufficiently to, in effect apply axial stress between the threads 12, 26 of the nut members 10, 24, respectively, and the associated threads of the externally threaded shaft 14. This relation is maintained since the lock washers 40, 42 will prevent the associated nuts 36, 38 from backing off their respective threaded shanks 20, 22.
An alternative embodiment of the invention is illustrated in FIG. 3. The illustrated embodiment differs from the embodiment illustrated in FIGS. 1 and 2 in the structure of the spacing boss members. More specifically, the boss members 16 and 28 of the embodiment of FIGS. 1 and 2 are formed from the material of the with the threads engaged by the threads 12 of the nut member 10.
The application of the lock nut assembly of the invention is accomplished by initially causing the annular nut member 10 to be received on the externally threaded shaft 14 and rotated onto the threads of the shaft 14. As the nut member 10 is rotated and moved axially of the shaft 14, the threads 26 of the second nut member 24 become threadably engaged on the threads of the shaft 14. It will be understood that engagement of the threads 26 of the second nut member 24 is facilitated due to the floatable relation between the nut members 10 and 24. The nut member 10 is then tightened, preferably by a torque wrench until the desired torque is reached. Next, the nuts 36, 38 are tightened sufficiently to, in effect apply axial stress between the threads 12, 26 of the nut members 10, 24, respectively, and the associated threads of the externally threaded shaft 14. This relation is maintained since the lock washers 40, 42 will prevent the associated nuts 36, 38 from backing off their respective threaded shanks 20, 22.
An alternative embodiment of the invention is illustrated in FIG. 3. The illustrated embodiment differs from the embodiment illustrated in FIGS. 1 and 2 in the structure of the spacing boss members. More specifically, the boss members 16 and 28 of the embodiment of FIG. 1 and 2 are formed from the material of the respective nut members 10 and 24, while in the alternative embodiment of FIG. 3 the corresponding boss members are formed by separate elements which are brazed or otherwise affixed to one or the other or both of the nut members. More specifically, in describing the embodiment of FIG. 3, like or similar elements with those of the embodiment of FIGS. 1 and 2 will be indicated by prime reference numerals and a detailed description will not be made. Accordingly, it will be noted that the annular nut member 10' is provided with a pair of diametrically spaced boss members 50, 52 which are brazed to the surface of the nut 10' which is in facing relative to the second nut member 24'. In other respects, the assembly of FIG. 3 functions in the same manner as that illustrated as described in respect of FIGS. 1 and 2.
In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiments. However, it should be understood that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope. | A lock nut assembly for vehicle axles includes a pair of cooperative annular nut members hang threads formed on the inner peripheral surfaces compliment--and cooperating with the externally threaded shank of axle spindle. The nut members are coupled together threaded fastener means and spaced axially from one another. The threaded fasteners are to be tightened when the nut members are tightened on the threaded axle spindle to form a high stressed clamping force between the threads of the nut members and the threads of the axle spindle. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a portable radiation image taking apparatus which is constructed such that a grid and a photo timer are attachable to the outside of a case.
[0003] 2. Related Background Art
[0004] Up to now, in general, an apparatus that emits a radiation to an object and detects an intensity distribution of the radiation transmitted through the object to obtain a radiation image of the object has been widely used in an industrial nondestructive testing and a field of medical diagnosis. As a general method for the above image taking, there is an X-ray film/screen method. This is a method of conducting image taking using a combination of a photosensitive film and a phosphor sensitive to an X-ray. A sheet-shaped rare earth phosphor that emits light when it is irradiated with the X-ray is held in contact with both surfaces of the photosensitive film. The X-ray transmitted through the object is converted into visible light by the phosphor and the visible light is captured in the photosensitive film. A latent image formed on the photosensitive film can be visualized by development using chemical treatment.
[0005] On the other hand, along With a recent progress in digital techniques, a method of converting a radiation image into an electrical signal, image-processing the electrical signal, and then reproducing the image-processed electrical signal as a visible image on a CRT or the like to obtain a high quality radiation image is required. With respect to such a method of converting the radiation image into the electrical signal, there has been proposed a radiation image recording and reproducing system as described in JP 55-012429 A, JP 56-011395 A, or the like, in which a radiation transmission image is temporarily stored as a latent image in the phosphor and the phosphor is irradiated with excitation light such as laser light later to photoelectrically read out the latent image and output it as a visible image.
[0006] Also, along with a recent progress in semiconductor process techniques, an apparatus that similarly takes a radiation image using a semiconductor sensor has been developed. Because such a system has a much wider dynamic range than that in the conventional radiation photography system using a photosensitive film, there is an economic advantage that a radiation image which is not influenced by a variation in radiation exposure amount can be obtained. Simultaneously, as compared with the conventional photosensitive film method, there is an advantage that chemical treatment is unnecessary and an output image can be immediately obtained.
[0007] [0007]FIG. 7 shows a conventional example of such a radiation image taking apparatus. An image taking unit 103 of an X-ray image taking apparatus includes an X-ray detection sensor 104 . An object 102 is irradiated with an X-ray generated by an X-ray generating apparatus 101 . The X-ray transmitted through the object 102 is detected by photoelectric conversion elements which are arranged in two-dimensional grid in the X-ray detection sensor 104 . An image signal outputted from the X-ray detection sensor 104 is processed into a digital image by an image processing unit 107 and an X-ray image of the object is displayed on a monitor 108 .
[0008] A scattered X-ray removing grid (hereinafter referred to as a grid) 105 is provided in the inner portion of the image taking unit 103 . The grid 105 is used for removing a scattered X-ray produced in the inner portion of the object (for example, a human body) by the X-ray irradiation to improve a contrast of the X-ray image. In the case where image taking is conducted, the grid 105 is located between an X-ray tube and a detector such as a photosensitive film.
[0009] [0009]FIG. 8 is a schematic sectional view of the grid. The X-ray is emitted from the A-direction on the left side in FIG. 8. In the grid 105 , foils 201 made of a material having a large X-ray absorbency index and intermediate materials 202 having a small X-ray absorbency index are alternately laminated. In general, lead is used for the foils 201 having the large X-ray absorbency index. In addition, aluminum, paper, wood, a synthetic resin, a carbon fiber reinforced resin, or the like is used as the intermediate material 202 having the small X-ray absorbency index. The periphery of the laminate is covered with a cover made of aluminum, a carbon fiber reinforced resin, or the like, which is indicated by reference numeral 200 .
[0010] In many cases, the grid 105 is a convergent grid. That is, a central foil which is represented by reference symbol 201 a and located immediately under an X-ray source (the X-ray generating apparatus 101 ) is perpendicular to the cover 200 . Foils represented by foils 201 b are slanted at larger angles toward the X-ray source as their positions are closer to the end of the grid. In the case of the convergent grid, it is necessary to conduct image taking while adjusting a distance between the grid and the X-ray source and aligning the center of the grid and the center of the X-ray source with each other. On the other hand, there is a grid in which the foils are not slanted. This is called a linear grid.
[0011] Also, a photo timer for X-ray dose measurement (hereinafter referred to as a photo timer) 106 is provided in the inner portion of the image taking unit 103 . The purpose of using the photo timer 106 is to measure a dose of an X-ray which actually reaches the detector (the X-ray detection sensor 104 ) in order to obtain a preferable image by adjusting it to a desirable X-ray dose. In addition, the purpose of using the photo timer 106 is to prevent a person to be examined from being exposed to a large dosage of X-rays. The photo timer 106 is used for terminating the generation of the X-ray in the X-ray generating apparatus 101 when the measured X-ray dose reaches a predetermined value. Therefore, the photo timer 106 is located between the grid 105 and the detector (X-ray detection sensor 104 ).
[0012] Up to now, such a kind of image pickup apparatus has been placed in a radiation room and used therein. However, in recent years, in order to enable image taking at a high speed and on a wide range section, a potable type image taking apparatus (which is also called an electronic cassette) is desired.
[0013] It is required that such an electronic cassette is thin and light in weight and has a high mechanical strength. In the image taking using the cassette, there is the case where the person to be examined mounts the cassette. In addition, there is a fear that an impact such as a drop or a collision is applied to the cassette due to its portability. Therefore, it is necessary to greatly improve a mechanical strength as compared with a conventional stationary image taking unit.
[0014] A schematic structure of the electronic cassette will be described with reference to a side cross section shown in FIG. 9. With respect to the electronic cassette used for the above-mentioned X-ray image taking, an X-ray detection panel 111 is two-dimensionally fixed onto a base 112 made of a metal in order to improve a strength with respect to a static pressure and bending. Further, an outer covering unit 114 is constructed so as to store the X-ray detection panel 111 , the base 112 , a circuit board 113 that processes electrical signals, and the like. In order to obtain a mechanical strength, a metal is used also for the outer covering unit 114 . Note that, because a reduction in weight is also required, a light metal such as aluminum or magnesium is employed. In addition, a cover 115 made of a material such as a CFRP having preferable X-ray permeability is provided on an X-ray incident surface side.
[0015] A scattered radiation amount depends on the structure of the object. For example, in the case of a human body, the scattered radiation amount is large in the chest and the abdomen and is relatively small in the arms and legs. Here, because the grid reduces an X-ray transmitting therethrough, the image taking without using the grid can be conducted at a dose smaller than in the case where the image taking is conducted using the grid. Therefore, in many cases, the grid is used for conducting the image taking on a section in which the scattered radiation amount is large because an image quality is given a high priority, and the image taking without the grid is conducted on a section in which the scattered radiation amount is relatively small in order to reduce a dose. In addition, an optimum grid specification is changed according to a section.
[0016] It is considered that the cassette is used for various sections. Accordingly, it is desirable that the grid is constructed so as to be easily detachably attachable according to a section on which the image taking is conducted. In the case of the conventional stationary type, a detachably attachable mechanism for the grid can be constructed in the image taking unit without causing a problem. However, in the case of the electronic cassette, it is disadvantageous that an opening portion for grid attachment and detachment is provided in a portion of the outer covering unit in view of a strength.
[0017] On the other hand, in the case of the chest and the abdomen, a dose of the X-ray which reaches the X-ray detection panel 111 is generally changed depending on the body shape (fat content) of the person to be examined. Therefore, the photo timer is used in many cases. However, in the case of the image taking of the arms and legs and the like or the cassette image taking in doctor's rounds or the like, the frequency in use of the photo timer is low. Thus, it is desirable that the photo timer for the electronic cassette is detachably attachable. In addition, if the photo timer is attached, the thickness of the entire cassette increases by the thickness of the photo timer. Thus, in the case where the cassette is placed below the person to be examined, it is not desirable to attach the photo timer to the cassette.
[0018] In the conventional techniques as described above, it is desirable to provide a radiation image taking apparatus which is constructed such that a grid and a photo timer are selectively detachably attachable to an image taking unit and includes the image taking unit which is thin and light in weight, and has a high mechanical strength with respect to a static pressure, bending, an impact, and the like.
SUMMARY OF THE INVENTION
[0019] According to one aspect of the present invention, there is provided a radiation image taking apparatus comprising:
[0020] a radiation detecting unit that has a detection surface in which a photoelectric conversion element is arranged, and converts a radiation into an electrical signal;
[0021] a case that contains the radiation detecting unit;
[0022] a grid unit which includes a grid that removes a scattered radiation and a grid frame; and
[0023] a photo timer unit which includes a photo timer that measures a dose of the radiation and a photo timer frame, wherein:
[0024] the grid unit is detachably attachable to the case through the grid frame, and the photo timer unit is detachably attachable to the case through the photo timer frame; and
[0025] one of a first mode in which the grid unit is attached to the case, a second mode in which the photo timer unit is attached to the case, and a third mode in which the grid unit is attached in the second mode can be used.
[0026] Other features and advantages of the present invention will be apparent from the following descriptions taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the descriptions, serve to explain the principle of the invention.
[0028] [0028]FIG. 1 is a structural view of a first embodiment;
[0029] [0029]FIG. 2 is a side cross sectional view of a first mode in which a grid module is attached to an image taking unit according to the first embodiment;
[0030] [0030]FIG. 3 is a side cross sectional view of a second mode in which a photo timer module is attached to the image taking unit according to the first embodiment;
[0031] [0031]FIG. 4 is a side cross sectional view of a third mode in which the grid module is attached to the image taking unit according to the second mode of the first embodiment;
[0032] [0032]FIG. 5 is a structural view of a second embodiment;
[0033] [0033]FIG. 6 is a side cross sectional view of a grid module according to the second embodiment;
[0034] [0034]FIG. 7 is a structural view of a conventional example;
[0035] [0035]FIG. 8 is a cross sectional view of a grid; and
[0036] [0036]FIG. 9 is a side cross sectional view of an image taking unit of the conventional example.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] A preferred embodiment of the present invention will be described in detail in accordance with the accompanying drawings.
[0038] The present invention will be described in detail with reference to embodiments shown in FIGS. 1 to 6 .
[0039] FIGS. 1 to 4 show an X-ray image taking apparatus according to a first embodiment of the present invention. FIG. 1 is a structural view of this embodiment. FIG. 2 is a side cross sectional view of a first mode in which a grid module is attached to an image taking unit. FIG. 3 is a side cross sectional view of a second mode in which a photo timer module is attached to the image taking unit. FIG. 4 is a side cross sectional view of a third mode in which the grid module is attached to the image taking unit according to the second mode.
[0040] In FIG. 1, the X-ray image taking apparatus includes an image taking unit 1 , a grid module 2 for scattered radiation removal, and a photo timer module 3 for radiation dose measurement. In this embodiment, it is possible to obtain the first mode in which the image taking unit 1 and the grid module 2 are combined, the second mode in which the image taking unit 1 and the photo timer module 3 are combined, and the third mode in which the second mode and the grid module 2 are combined.
[0041] First, the first mode will be described with reference to FIG. 2. FIG. 2 is a cross sectional view taken along the line B shown in FIG. 1.
[0042] An X-ray detection panel 11 is composed of a fluorescent screen 11 a, photoelectric conversion elements 11 b, and a substrate 11 c. A glass substrate is used as the substrate 11 c in many cases. This is because it is required that no chemical action with a semiconductor element is produced, there is a resistance to a temperature of a semiconductor process, and a size is stabilized. The photoelectric conversion elements 11 b are formed in two-dimensional arrangement on the above-mentioned glass substrate by a semiconductor process. A resin plate to which a phosphor of a metallic compound is applied is used as the fluorescent screen 11 a and integrally formed with the substrate 11 c by bonding.
[0043] The X-ray detection panel 11 having such a structure is fixed onto a base 12 made of a metal. A circuit board 13 that processes photoelectrically converted electrical signals is connected with the photoelectric conversion elements 11 b through a plurality of flexible print circuit boards 14 .
[0044] In the flexible print circuit boards 14 , signal lines and control lines which are used for reading electrical signals from the photoelectric conversion elements 11 b are wired. The flexible print circuit boards 14 are arranged in the outer region of the substrate 11 c. Each of the flexible print circuit boards 14 is led to the circuit board 13 located on the rear surface of the base 12 through the side of the base 12 . Thus, an X-ray image detection unit is completed.
[0045] The X-ray image detection unit is contained in the inner portion of a case main body 15 and fixed to the case main body 15 through a support portion of the base 12 . The X-ray image detection unit is hermetically sealed by a case cover 16 having X-ray permeability. Thus, the image taking unit 1 is constructed.
[0046] The grid module 2 is composed of a grid main body 21 and a frame 22 made of a metal. As described above, because the grid main body 21 has a layer structure in which an X-ray shield and an intermediate material with a low X-ray absorption are formed, the mechanical strength of the grid main body 21 is low. Therefore, the frame 22 made of the metal in which an opening portion 22 a for X-ray transmission is formed is mounted as a reinforcing frame to the grid main body 21 . Both sides of the frame 22 in the cross section are bent so as to be a substantially U-shape. Bending ends 22 b guide the image taking unit 1 so as to attach the grid module 2 to the image taking unit 1 in the C-direction shown in FIG. 1 while the bending part ends 22 b fit with step portions 15 a or groove portions 15 b which are provided in the image taking unit 1 . Here, because the grid module 2 is directly attached to the image taking unit 1 , the bending part ends 22 b are engaged with the step portions 15 a. When the grid module 2 is attached to the image taking unit 1 , the grid module 2 is engaged therewith by a biasing member (not shown) in which a resistance acts in the through direction.
[0047] A detector 17 in the inner portion of the image taking unit 1 and a detection member 23 inside the frame 22 of the grid module 2 are located to oppose to each other at the engaging position. When the detection member 23 is detected by the detector 17 , the completion of the attachment of the grid module 2 is recognized. In terms of specific configurations thereof, there are cited a magnet as the detection member 23 and a reed switch turned on/off by a magnetic force as the detector 17 . Accordingly, information indicating whether or not the grid module 2 is attached is simply obtained. In addition, a bar code index can be used as the detection member 23 and a line sensor can be used as the detector 17 . In this case, information related to a specification, such as a grid type can be also obtained. The information obtained by the detector 17 is sent as an image taking condition to a control unit side. Or it is possible to have a function of a control unit to the image taking unit 1 and to also make information record in the inner portion of the image taking unit 1 . Such information can be automatically recorded together with image information so that the convenience of an operator can be improved.
[0048] Next, the second mode will be described with reference to FIG. 3. FIG. 3 is a cross sectional view taken along the line A shown in FIG. 1.
[0049] A photo timer is composed of a detection unit 31 and an amplifying unit 32 that amplifies signals, and mounted onto a frame 33 made of a metal in which an opening portion 33 a for X-ray transmission is formed. The amplifying unit 32 is connected with a cable 34 for the photo timer, thereby connecting with an X-ray generating apparatus. The X-ray generating apparatus conducts a sequence in which X-ray irradiation is stopped when a predetermined radiation dose threshold value is detected.
[0050] As in the case of the frame 22 of the grid module 2 , both upper and lower ends of the frame 33 of the photo timer module 3 within the cross section are bent so as to be a substantially U-shape, and inserted to groove portions 15 c provided in the case main body 15 of the image taking unit 1 . The photo timer module 3 is guided along the groove portions 15 c in the D-direction shown in FIG. 1 by ends 33 b of the frame 33 and attached to the image taking unit 1 . In the attachment state, a detector 18 and a detection member 35 are located to oppose to each other. Therefore, as in the case of the grid module 2 , the completion of the attachment thereof or specification information can be recognized.
[0051] Further, the third mode will be described with reference to FIG. 4. FIG. 4 is a cross sectional view taken along the line B shown in FIG. 1.
[0052] As described in the conventional example, the third mode corresponds to the case where both the grid module and the photo timer module are used. With respect to the structure, the photo timer module 3 is formed above the image taking unit 1 and the grid module 2 is formed above the photo timer module 3 . In other words, the grid module 2 is attached to the second mode described above.
[0053] The grid module 2 is constructed so as to engage with one set of two opposite sides with respect to the square radiation incident surface of the image taking unit 1 . In addition, the photo timer module 3 is constructed so as to engage with the other set of two opposite sides with respect to the square radiation incident surface of the image taking unit 1 . Therefore, in the second mode in which the photo timer module 2 is attached, the opposite sides of the image taking unit 1 which are engaged with the grid module 2 are exposed to the outside. Here, in contrast to the first mode, the bending part ends 22 b of the frame 22 of the grid module 2 are inserted to the grove portions 15 b to attach the grid module 2 to the image taking unit 1 . The groove portions 15 b are formed at positions corresponding to a height at which the photo timer module 3 is attached to the image taking unit 1 . Therefore, the image taking unit 1 , the grid module 2 , and the photo timer module 3 are combined to obtain the layer structure as shown in FIG. 4. Because an additional detection member 24 is located at a position opposite to the detector 17 , the attachment states of both the photo timer module 3 and the grid module 2 can be recognized in this case.
[0054] Next, a second embodiment will be described with reference to FIGS. 5 and 6. FIG. 5 is a structural view of the second embodiment and FIG. 6 is a side cross sectional view of a grid module according to the second embodiment.
[0055] In the first embodiment, it is constructed such that the grid module and the photo timer module are attached to or detached from the image taking unit in the side direction of the image taking unit. In the case where the radiation image taking apparatus is attached to the base with a standing position or a recumbent position for use, there is the case where the grid module and/or the photo timer module cannot be attached or detached because of no side space. Therefore, in the second embodiment, it is constructed such that a grid module and a photo timer module are detachably attachable to the image taking unit in the X-ray incident direction.
[0056] First, the grid module 5 will be described by way of example. FIG. 6 is a cross sectional view taken along the line B shown in FIG. 5. A grid 51 is two-dimensionally fixed onto a frame 52 which is made of a metal and has an opening portion 52 a. In FIG. 6, two protruding portions 52 b which are bent so as to be a substantially U-shape are provided in the left end. On the other hand, two engaging members 53 are provided in the right end to a bending portion of the frame 52 which is bent in the vertical direction. Each of the engaging members 53 is composed of an elastic portion 53 a which vertically extends and a convex portion 53 b formed in the end of the bending portion.
[0057] Recesses 4 a and 4 b which are engaged with the grid module 5 are formed in the side of an image taking unit 4 . Although only one side is shown in FIG. 5, the identical recesses are formed on the opposite side. In the case of the attachment, first, the protruding portions 52 b are inserted into the recesses. After that, the grid module 5 is overlapped on the image taking unit 4 while the grid module 5 is rotated about the protruding portions 52 b. At this time, the engaging members 53 are warped by the elastic property of the elastic portion 53 a, so that the convex portion 53 b is inserted into the recesses.
[0058] Similarly, the photo timer module 6 can be also attached to the image taking unit 4 through recesses 4 c. In addition, the selection of the recesses 4 a and 4 b which are required for attaching the grid module 5 can be conducted according to whether or not the photo timer module 6 is attached.
[0059] Therefore, as in the first embodiment, the grid module 5 is constructed so as to engage with one set of two opposite sides with respect to the square radiation incident surface of the image taking unit 4 . In addition, the photo timer module 6 is constructed so as to engage with the other set of two opposite sides with respect to the square radiation incident surface of the image taking unit 4 . Thus, combinations of the first mode to the third mode can be realized.
[0060] As described above, according to the present invention, the radiation image taking apparatus is constructed such that the grid module and the photo timer module are selectively detachably attachable from the outside to the image taking unit. Therefore, it is unnecessary to provide the image taking unit with an opening portion for grid module attachment and detachment and an opening portion for photo timer module attachment and detachment. In addition, the image taking unit which is thin and light in weight and has a high mechanical strength can be realized. Thus, the radiation image taking apparatus can be applied to various image taking modes. In addition, a relatively low cost system can be provided, in which image taking using the stationary type, image taking in doctor's rounds, and the like are covered with a single image taking unit.
Other Embodiment
[0061] Note that the present invention may be applied to either a system constituted by a plurality of apparatuses (e.g., an image processing apparatuses, interfaces, radiographic apparatuses, X-ray generation apparatuses, and the like) or an arrangement that integrates an image processing apparatus and a radiographic apparatus, or the like.
[0062] The present invention is not limited to the above embodiments and various changes and modifications can be made within the spirit and scope of the present invention. Therefore to apprise the public of the scope of the present invention, the following claims are made. | A radiation image taking apparatus includes a case that contains a radiation detecting unit that has a detection surface in which a photoelectric conversion element that detects a radiation transmitted through an object is located, a grid unit which is detachably attachable to an outside of the case and removes a scattered radiation, and a photo timer unit which is detachably attachable to the outside of the case and measures a dose of the radiation. One of a first mode in which the grid unit is attached to the case, a second mode in which the photo timer unit is attached to the case, and a third mode in which the grid unit is attached to the second mode can be freely used in configuration. | 6 |
BACKGROUND OF THE INVENTION
The invention relates to a device for preventing uncontrolled acceleration of an elevator car of an elevator installation both in the upward direction and in the downward direction.
In elevator installations an elevator car is usually connected to a counterweight by a rope over a traction sheave which transmits driving action to the car. To ensure that in the case of a functional fault such as, for example, failure of the driving device, the elevator car is not accelerated in uncontrolled manner by the difference in weight between the elevator car and the counterweight, a corresponding safety device is prescribed. Because the counterweight is usually designed so that when the elevator car is carrying half the permitted rated load there is a state of equilibrium, uncontrolled acceleration can occur in both the downward direction and in the upward direction depending on whether the elevator car is carrying more or less than half the permitted rated load. The safety device must therefore respond both when there is uncontrolled acceleration in the downward direction and in the upward direction.
A device for preventing uncontrolled acceleration of an elevator car in an elevator installation is known, for example, from EP 0 440 839 A1. The safety device according to that printed publication responds both in the case of an uncontrolled acceleration in downward direction and an uncontrolled acceleration in upward direction. To detect the uncontrolled acceleration of the elevator car, a governor rope is provided which is independent of the traction rope and which runs endlessly over an upper return pulley and a lower return pulley. Provided on the lower return pulley is a weight to keep the governor rope constantly taut. Located on the upper return pulley is an overspeed governor. The elevator car is connected to the governor rope via an actuating lever which serves as a tripper and which, when the elevator car is running undisturbed, is constantly transported with the latter so that the speed of rotation of the upper return pulley is proportional to the speed of the elevator car. The overspeed governor detects the speed of rotation of the upper return pulley and is so designed that, when a limit speed of rotation of the upper return pulley is exceeded, the overspeed governor blocks the latter so that the upper return pulley is brought to rest. Because the governor rope is still transported by the elevator car, the governor rope slips over a groove provided in the upper return pulley and thereby experiences a frictional resistance which causes a tripping force to be transmitted via the governor rope to the tripping mechanism of the braking device. Thereupon, the braking device responds and presses brake shoes against a guiderail of the elevator installation so that the elevator car is braked and held. Different brake shoes are provided for braking/holding the elevator car in the downward direction and the upward direction respectively.
As shown in detail below by means of FIGS. 10 and 11, the force which acts on the fall of the governor rope connected to the tripper depends to a substantial extent on whether the elevator car is moving in a downward or an upward direction. Stated simply, if the elevator car is moving upward, the fall of the governor rope connected to the tripper pulls on the weight of the lower return pulley directly. On the other hand, if the elevator car is moving downward, the fall of the governor rope connected to the tripper pulls on the weight of the lower return pulley via the stationary upper return pulley so that in this case the force acting on the rope fall connected to the tripper is substantially increased by friction.
The dimensions of the safety device, particularly of the weight connected to the lower return pulley and of the geometry of the slot provided on the upper return pulley, over which the governor rope is pulled when the upper return pulley is stationary, must therefore be based on the braking operation of the elevator car moving in the upward direction because the tripping force for this case is lower. On the other hand, this also means that the tripping force when the elevator car is moving in a downward direction becomes so large that considerable problems arise with the dimensioning of the governor rope and of the tripper of the braking device, because the governor rope and the tripper must withstand this very high tripping force in the downward direction.
In EP 0 440 839 A1 the suggestion is made of arranging a compensation spring in the governor rope above the tripper. However, this compensation spring increases even further the tripping force in the downward direction, which is already too high anyway, and is therefore disadvantageous.
SUMMARY OF THE INVENTION
The objective of the invention is to create a device for preventing uncontrolled acceleration of an elevator car of an elevator installation in which the tripping force transmitted to the tripper of the braking device is limited.
According to the invention, it is proposed to connect the tripper of the braking device with the governor rope via a slipping connection so that the governor rope slips on the slipping connection if a force is transmitted from the governor rope to the tripper of the braking device which is substantially greater than the tripping force required to trip the braking device. By means of the proposed solution according to the invention, the maximum tripping force which is transmitted is limited, and the tripper of the braking device and the governor rope are thereby protected against overloading. In this manner, the components of the device can be so designed that on the one hand a tripping force is generated sufficient to trip the tripper of the braking device with certainty and thereby arrest an acceleration of the elevator car in the upward direction, but so that on the other hand the tripping force when arresting the elevator car in the downward direction is limited, which prevents overloading the tripper and governor rope.
The slipping connection can be so adjusted that the governor rope only slips on the slipping connection when the elevator car is braked in the downward direction. When the elevator car is braked in the upward direction, the governor rope then slips as hitherto over the stationary upper return pulley without activating the slipping connection according to the invention. Because a much larger force acts on the governor rope when braking the elevator car in the downward direction than when braking in the upward direction, it is sufficient for the slipping connection to slip in the downward direction. The slipping connection can be set with some margin of safety above the tripping force required to trip the braking device.
The slipping connection can be arranged immediately below the rope connector that connects the free ends of the governor rope to each other.
The slipping connection consists preferably of a base plate and a pressure plate which presses against the base plate with a specified compressive force, the governor rope being gripped between the base plate and the pressure plate. To generate the compressive force there is at least one tension screw which passes through and beyond a drilled hole of the pressure plate and can be screwed into a thread of the base plate. The depth to which the screw can be screwed into the thread, and therefore the compressive force, is limited by a tightening stop.
The compressive force can be generated by a compression spring compressed between the base plate and a projection of the tension screw, the compression spring consisting preferably of several cup springs arranged in a stack. The tightening stop can take the form of a sleeve surrounding the tension screw.
The governor rope is preferably guided in a groove in a surface of the base plate and/or the pressure plate which has a preferably triangular cross section. At the ends of the base plate and of the pressure plate the groove opens out into an area which preferably opens out both in the direction of the surface and perpendicular to the surface of the base plate and pressure plate respectively. The tripper of the braking device is fastened to either the pressure plate or the base plate.
BRIEF DESCRIPTION OF THE DRAWINGS
An exemplary embodiment of the invention is described below by reference to the drawings.
The drawings show:
FIG. 1 is an overall view of an exemplary embodiment of the device according to the invention;
FIG. 2 is an exploded view of the governor rope, the rope connector, and the slipping connection;
FIG. 3 shows the governor rope, the rope connector, and the slipping connection in the assembled state;
FIG. 4 is a plan view of the slipping connection;
FIG. 5 is a cross section on line A—A in FIG. 4;
FIG. 6 is a cross section on line B—B in FIG. 4;
FIG. 7 is a plan view of the base plate of the slipping connection;
FIG. 8 is a side view of the base plate of the slipping connection;
FIG. 9 is a cross section on line A—A in FIG. 8; and
FIGS. 10 and 11 are force diagrams.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an overall view of the device according to the invention for preventing uncontrolled acceleration of an elevator car of an elevator installation.
Only the car frame 2 of an elevator car 1 is shown. The car frame 2 of the elevator car 1 is guided in a vertical path by an upper guide 3 and a lower guide 4 along a guiderail 5 indicated only by the broken line. The elevator car 1 is suspended on a traction rope not shown in the drawing which is reversed over a traction sheave at the upper end of the elevator hoistway and connected to a counterweight. Driving action is applied to the elevator car by the traction sheave. As a rule, the counterweight is so dimensioned that the counterweight is in equilibrium with the elevator car 1 when the elevator car 1 is loaded with approximately half its maximum rated load. Occurrence of an operational fault, especially failure of the drive device, can cause uncontrolled acceleration of the elevator car 1 due to the difference in weight between the elevator car 1 and the counterweight. If the elevator car 1 is loaded with less than half its rated load, this acceleration takes place in the upward direction. On the other hand, if the elevator car 1 is loaded with more than half its rated load, this uncontrolled acceleration takes place in the downward direction. To prevent this uncontrolled acceleration, a braking device 6 is provided which prevents uncontrolled acceleration in both the upward and the downward direction and which can be tripped by a tripper 7 . A braking device 6 of a similar type is known, for example, from DE 296 19 729 U1 and EP 0 825 145 A1, and is described in outline only below.
The tripper 7 consists of a lever 9 articulated on a suspension 8 and of a rod 10 connected to the lever 9 which engages in a cam plate 12 supported in a bearing 11 . When the lever 9 in FIG. 1 tilts upward, the rod 10 is pushed upward and turns the cam 12 so that a first brake element 13 is pressed into contact with the guiderail 5 (shown only as a broken line) so that the guiderail 5 is gripped between a brake shoe 14 and the first brake element 13 . The gripping force is provided by two cup spring assemblies 15 and 16 acting on the brake shoe 14 . Deceleration of the elevator car 1 then takes place by removal of metal from the guiderail 5 (shown only as a broken line). The braking process described above relates to braking the elevator car 1 in the case of uncontrolled acceleration in the downward direction.
To decelerate or arrest the elevator car 1 in the case of uncontrolled accelerating movement in the upward direction, the lever 9 in FIG. 1 is tilted downward and the rod 10 pushed downward. As a result, a second brake element 17 is brought into engagement with the guiderail 5 so that the guiderail 5 is gripped between the brake shoe 14 and the second brake element 17 .
Tripping of the tripper 7 of the braking device 6 takes place via a governor rope 18 , with which the elevator car 1 is connected by the tripper 7 of the braking device 6 . In the exemplary embodiment, the governor rope 18 takes the form of an endless rope running over an upper return pulley 19 and a lower return pulley 20 . By means of a weight 21 acting on the lower return pulley 20 via a rod 22 which is articulated in a bearing 23 , the governor rope 18 is held taut between the upper return pulley 19 and the lower return pulley 20 . The free ends 24 and 25 of the governor rope 18 are joined to each other by a rope connector 26 .
On the upper return pulley 19 there is an overspeed governor 27 which, on exceeding a specified speed of rotation, brings the upper return pulley 19 to rest, i.e. blocks it. Overspeed governors 27 of this type are known, constructed in various ways.
During normal operation of the elevator installation, the governor rope 18 is transported congruently with the elevator car 1 , and the upper return pulley 19 is in its unblocked state. Because the speed of the governor rope 18 is the same as the speed of the elevator car 1 , the rotational speed of the upper return pulley 19 is proportional to the speed of the elevator car 1 . If the rotational speed of the upper return pulley 19 exceeds a specified limit value, the overspeed governor 27 blocks the upper return pulley 19 so that the governor rope 18 is in slipping contact with the stationary upper return pulley 19 . As a result, a force component is exerted on the governor rope 18 which the latter transmits to the tripper 7 of the braking device 6 , which in turn causes the braking device 6 to be tripped.
Problematical with such a device for preventing uncontrolled acceleration of the elevator car 1 is that when the elevator car 1 moves in the downward direction, a much greater braking force acts on the governor rope 18 than when the elevator car 1 moves in the upward direction. This situation is explained in greater detail below by reference to FIGS. 10 and 11.
FIG. 10 illustrates the situation regarding forces on the governor rope 18 , on the upper return pulley 19 , and on the lower return pulley 20 when braking the elevator car 1 in the downward direction. After the upper return pulley 19 has been brought to rest, the left-hand fall 18 a of the governor rope 18 in FIGS. 1 and 10 is at first transported downward. On both the left-hand fall 18 a of the governor rope 18 and on the right-hand fall 18 b of the governor rope 18 a force G/2 equivalent to half of the weight 21 acts via the corresponding lever on the rod 22 . Acting against this force in both the left-hand fall 18 a and in the right-hand fall 18 b of the governor rope 18 is a vectorially opposite counterforce G/2. Also acting on both the left-hand fall 18 a and on the right-hand fall 18 b of the governor rope 18 is a force G S attributable to the weight of the respective fall of the rope. In this case, the governor rope is pulled to the left over the upper return pulley 19 . The right-hand force on the stationary upper return pulley 19 is given by the resultant force S 1 , which is made up of the rope-weight force G S and the force G/2. Acting on the left-hand fall 18 a of the governor rope is a correspondingly greater force S 2 , which is correspondingly increased by the friction on the groove of the upper return pulley 19 . To trip the braking device 6 , a tripping force can be used consisting of a force F 1 acting vectorially downward which results from the difference between the force S 2 acting in the opposite direction, the rope weight force G S plus the force G/2.
FIG. 11 illustrates the situation when braking the elevator car 1 in downward direction. In this case the governor rope 18 is pulled to the right over the stationary upper return pulley 19 . The right-hand force S 1 on the upper return pulley 19 is accordingly greater than the left-hand force S 2 . The result is therefore a vectorially upward directed force F 2 on the left-hand fall 18 a of the governor rope 18 , which can be used as tripping force for the braking device 6 .
The weight force G acting on the lower return pulley 20 , and the geometry of the groove of the upper return pulley 19 which determines the relationship between the forces S 1 and S 2 , must be so dimensioned that when the elevator car 1 is braked in the upward direction, the available tripping force F 2 is still sufficient to trip the braking device 6 with certainty. Inevitably, when the elevator car 1 is braked in the downward direction, the resulting tripping force F 1 is much greater, as FIG. 10 shows.
The same result is obtained if the tripping force F for braking the elevator car either downward or upward is determined by calculation. For the case of braking the elevator car 1 downward, the following equations apply:
S 2 =G S +{fraction (G/2)}+F 1 (1)
S 2 =S 1 +·e f (μ)·α (2)
S 1 =G S +{fraction (G/2)} (3)
For the case of braking the elevator car 1 in the upward direction, the following equations apply:
S 2 =G S +{fraction (G/2)}−F 2 (4)
S 1 =S 2 ·e f (μ)·α (5)
S 1 =G S +G S +{fraction (G/2)} (6)
In this system of equations the symbols have the following meanings:
S 1 tension on the right of the upper return pulley 19
S 2 tension on the left of the return pulley 19
G S half the weight of the governor rope 18
G tension acting on the lower return pulley 20 caused by the weight 21
F ½ force acting on the tripper 7
α angle of wrap on the upper return pulley 19 (α=180°)
f(μ) coefficient of friction depending on the shape of the groove of the upper return pulley 19
Taking the above equations (4), (5), and (6), and assuming a normal geometry for the groove on the upper return pulley 19 , to calculate first the weight force G of the weight 21 acting on the lower return pulley 20 to obtain a specified tripping force in the upward direction F 2 , and if the required weight force G determined in this manner is inserted in the equations (1), (2), and (3), the effective tripping force acting downward F 1 is obtained, which depends on the effective tripping force acting upward F 2 . For example, if certain tripping of the braking device 6 requires a tripping force of 400N, and if the weight 21 is so dimensioned that these 400N are attained in the upward direction, a force of approximately 1550N is obtained for the tripping force in the downward direction F 1 , in other words a force almost four times as large as the upwardly acting tripping force F 2 . This means that both the governor rope 18 and the tripper 7 , as well as the associated braking device 6 must be able to withstand this very high tripping force in the downward direction, which requires special design measures and thereby increases the manufacturing costs for the braking device 6 and the tripper 7 . Furthermore, a standardized braking device 6 with associated tripper 7 which has official type approval for braking the elevator car in the downward direction, cannot necessarily be used in the upward direction because of the excessive tripping force.
To solve this problem, the present invention proposes to limit the force transmitted to the tripper 7 by connecting the tripper 7 of the braking device 6 to the governor rope 18 by means of a slipping connection 30 . The governor rope 18 slips on the slipping connection 30 if a force is transmitted from the governor rope 18 onto the tripper 7 which is significantly greater than the tripping force needed to trip the braking device 6 . If the tripping force required is, for example, 400N, the slipping connection 30 can be set so that the latter slips at, for example, 800N. This represents an adequate safety margin relative to the required tripping force of 400N and limits the tripping force of 1550N in the downward direction, which would otherwise occur, to the stated 800N.
An exemplary design embodiment of this slipping connection 30 is illustrated in FIGS. 2 to 9 . FIG. 2 shows the individual parts and their positions for assembly, while FIG. 3 shows the fully assembled slipping connection 30 , which is preferably mounted below the rope connector 26 on the governor rope 18 . Mounting in a position directly under the rope connector 26 has the advantage that when the slipping connection 30 slips on the governor rope 18 there is an unlimited length available for slipping downward.
In the illustrated exemplary embodiment, the slipping connection 30 comprises a base plate 31 , two tension screws 33 , two compression springs 34 , two tightening stops 35 in the form of sleeves, and assembly screws 36 . Between the tension screws 33 and the compression springs 34 first washers 37 are laid, while between the installation screws 36 and the lever 9 of the tripper 7 second washers 38 are laid. On the base plate 31 there is a groove 40 to guide the governor rope 18 . It is self-evident that as an alternative, the groove 40 can also be formed on the pressure plate 32 , or on both the pressure plate 32 and the base plate 31 .
The exemplary embodiment of the slipping connection 30 illustrated in FIGS. 2 and 3 is described in detail below by reference to FIGS. 4 and 6. FIG. 4 shows a plan view of the slipping connection 30 , FIG. 5 a section along the line A—A in FIG. 4, and FIG. 6 a section along the line B—B in FIG. 4 . Elements which have already been described are given the same reference numbers to facilitate identification.
As can be seen from FIG. 5, the governor rope 18 is gripped between the base plate 31 and the pressure plate 32 . A threaded shaft 50 of each tension screw 33 is screwed into a thread 51 of the base plate 31 . By tightening the tension screws 33 , an associated compression spring 34 , which in the exemplary embodiment illustrated consists of several cup springs 53 arranged in a stack, is gripped between a screw head 52 of the associated tension screw 33 , or more precisely the washer 37 , and the pressure plate 32 . The compressive force exerted by the compression spring 34 depends on the pretension, and therefore on the depth to which the threaded shaft 50 is screwed into the baseplate 31 . The depth to which the tension screw 33 is screwed into the base plate 31 is limited by the tightening stop 35 . In the illustrated exemplary embodiment, each tightening stop 35 takes the form of a sleeve which surrounds the threaded shaft 50 of the respective tension screw 33 . Provided in the pressure plate 32 for each tension screw 33 and each tightening stop 35 is a drilled hole 54 through which both the threaded shaft 50 of the tension screw 33 and the sleeve-shape tightening stop 35 pass and project. The sleeve-shaped tightening stop 35 is gripped between the screw head 52 , or more precisely between the washer 37 , and the surface 55 of the base plate 31 .
In the illustrated exemplary embodiment, two tension screws 33 are provided. It is self-evident that within the scope of the invention only one single tension screw 33 , or three or more tension screws 33 , can be used.
As can be seen from FIG. 6, in the exemplary embodiment the pressure plate 32 has threaded holes 56 into which the assembly screws 36 can be screwed, so that the lever 9 of the tripper 7 is connected to the pressure plate 32 . As an alternative, it is self-evidently also possible to connect the lever 9 of the tripper 7 to the base plate 31 .
Due to the pretension of the compression springs 37 being defined, the force with which the governor rope 18 is gripped between the tension plate 32 and the base plate 31 is defined. By correspondingly dimensioning the length of the sleeve-shaped tightening stop 35 , the pretension of the compression springs 37 can be exactly and reproducibly determined. This permits an exact and reproducible determination of that force between the governor rope 18 and the tripper 7 at whose being exceeded the governor rope 18 slips on the slipping connection 30 .
The geometry of the groove 40 formed in the base plate 31 is described in greater detail below by reference to FIGS. 7, 8 , and 9 . FIG. 7 shows a plan view of the base plate 31 , FIG. 8 shows a side view of the base plate 31 illustrated in FIG. 7, and FIG. 9 shows a section along the line A—A in FIG. 8 . Elements which have already been described are given the same reference numbers to facilitate identification.
Visible in FIG. 7 is the groove 40 which runs longitudinally in the surface 55 of the base plate 31 , and which widens at each end 60 and 61 of the base plate 31 into an opening area 62 and 63 which will be described in more detail. Visible in FIG. 8, which shows a side view of the base plate 31 looking onto one of the two ends 60 , is the preferred triangular cross section of the groove 40 . Also visible is that in the opening area 62 , the groove 40 opens both in the direction of the surface 55 and also perpendicular to the surface 55 of the base plate 31 .
Visible in FIG. 9 is the section along the line A—A in FIG. 8 in which the preferred opening angle of 15° can be seen. The angle formed by the two flanks of the triangular groove 40 is preferably approximately 90°.
By means of the opening areas 62 and 63 , an abrupt kinking of the governor rope 18 is avoided, should the longitudinal axis 64 of the groove 40 not run exactly parallel to the direction of tension of the governor rope 18 .
As already mentioned, it is self-evident that the groove 40 can also be alternatively or additionally provided on the pressure plate 32 .
Within the scope of the invention it is also conceivable that not only the upper return pulley 19 or the lower return pulley 20 is brought to rest by the response of the overspeed governor 27 , but the governor rope 18 itself. For this purpose, the pulleys 19 and 20 can take the form of, for example, synchronized tangential pulleys instead of return pulleys. By means of the flexible slipping connection 30 , created according to the invention between the tripper 7 and the governor rope 18 instead of the rigid connection used hitherto, the slipping connection 30 which is connected via the tripper 7 and the braking device 6 to the elevator car 1 can slip both in the upward and in the downward direction after the tripping force required to trip the braking device 6 is exceeded. This increases the flexibility of the construction of the safety device.
Thus, while there have been shown and described and pointed out fundamental novel features of the present invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the present invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Substitutions of elements from one described embodiment to another are also fully intended and contemplated. It is also to be understood that the drawings are not necessarily drawn to scale but that they are merely conceptual in nature. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto. | A device for preventing uncontrolled acceleration of an elevator car installed in an elevator installation. The device has a limiting cable guided over rollers in a direction of movement of the elevator car. A braking device which is joined to the elevator car is connected to the limiting cable by a release and brakes the elevator car in both a downward and upward direction when the limiting cable transmits a predetermined release force to the release. A speed limiter is connected to one of the rollers and stops the roller when the traveling speed of the elevator car exceeds a predetermined limiting speed either in a downward or upward direction. The release of the braking device is connected by a slide connection to the limiting cable for limiting the force transmitted to the release so that the limiting cable slides through on the side connection when a force is significantly larger than the release force required for releasing the braking device is transmitted from the limiting cable to the release of the braking device. | 1 |
FIELD OF THE INVENTION
[0001] The invention relates generally to the field of image processing, and in particular to an image processing method for removing streaks in multi-band digital images (images consisting of three or more spectral bands). The invention is particularly useful in removing streaking in multi-band digital images that are acquired by a linear image sensing array, but may also be used to remove streaks in conventional color film that are caused by the camera or processing equipment.
BACKGROUND OF THE INVENTION
[0002] Multi-band imaging sensors typically are designed such that each band of the imaging system is sensitive to a pass-band of electromagnetic radiation. For example, a standard color imaging system consists of three bands (or arrays of detectors) sensitive to red, green, and blue light, respectively. Imaging systems such as multi-spectral or hyper-spectral systems contain many detector bands. These systems may contain spectral bands sensitive to non-visible parts of the electromagnetic spectrum such as to NIR (near-infrared), SWIR (short-wave infrared) or MWIR (mid-wave infrared) in addition to bands sensitive to red, green, and blue light. Color composite imagery is commonly formed from multi-spectral imagery and hyper-spectral imagery by mapping three selected bands to the red, green, and blue bands of an output display device such as a video monitor, or a digital color printer.
[0003] Every detector of a given spectral band in an electronic image sensor, such as a CCD image sensor, may have a different response function that relates the input intensity of light (or other electromagnetic radiation) to a pixel value in the digital image. This response function can change with time or operating temperature. Image sensors are calibrated such that each detector in a given spectral band, has the same response for the same input intensity (illumination radiance). The calibration is generally performed by illuminating each detector of the spectral band with a given radiance from a calibration lamp and then recording the signal from each detector to estimate the response function of the detector. The response function for each detector is used to equalize the output of all of the detectors such that a uniform illumination across all of the detectors will produce a uniform output. This calibration is typically performed separately for each band of a multi-band imaging system.
[0004] [0004]FIG. 1 shows a schematic of an image acquired by a linear image sensing arrays. In such an image, if errors in estimating the response curve of a detector are different from the errors in the response curve of an adjacent detector, the detector responses will not be equalized and streaking 2 will appear in the image along the scan direction indicated by arrow A. Since these calibration errors can occur within each band of a spectral imaging system, and several bands of a spectral imaging system are often combined together to form a color composite image, the streaking 2 may appear in various colors. Often to achieve a very long array, several image sensor chips are joined together to form a single linear image sensor. Slight differences in response between chips (due to variations in sensor chip manufacturing, or sensor electronics processing) can lead to large calibration errors between chips. When calibration errors occur between chips, the streaking is generally referred to as banding, as illustrated at reference numeral 4 .
[0005] Even when the detectors are calibrated to minimize the streaking in the image, some errors from the calibration process are unavoidable. Typically, a spectral filter is placed on a given detector, or sensor chip to create an imaging band sensitive to a specific region in the electromagnetic spectrum. Depending on the architecture of the sensor array, it may be necessary to have several spectral filters of the same bandpass to cover the entire array. Often, due to the variations in the spectral filter manufacturing process, the filters that are placed over the detectors in a given band may be slightly different in spectral bandpass and spectral shape. In addition, material variations, and the angle of incidence of light on a spectral filter, causes additional spectral variations depending on the position of the spectral filter on the sensor array. As a result, each detector within a spectral band is sensitive to a slightly different spectrum of light, but they are all calibrated using the same calibration lamp with a broad, non-uniform spectrum. Since the scene spectrum is unknown, the calibration process assumes that the spectrum of the calibration lamp and scene are identical. The spectrum of the calibration lamp will usually be somewhat different than the spectrum of the scene being imaged, hence calibration errors will occur. This calibration error is also referred to as spectral banding. Calibration errors also occur because the calibration process includes an incomplete model of the complete optical process and because the response function for each detector changes over time and operating temperature.
[0006] Streaking can be seen in uniform areas of an image acquired by a linear detector and become very apparent when the contrast of the image is enhanced. Calibration differences between the red, green, and blue detectors of color imaging systems (or any of the bands in a multi-spectral or hyper-spectral imaging system) produce streaks of varying colors in the composite color image. These streaks not only reduce the aesthetic quality of digital images but can impact the interpretability of features in the images. Streaking also severely degrades the performance of pattern recognition, feature extraction algorithms, image classification algorithms and automated or semi-automated target recognition algorithms.
[0007] Streaks can be attenuated by reducing the contrast of each image band or by blurring each image band in a direction perpendicular to the streaking, but these methods degrade the quality of the overall image. Previously developed algorithms designed to remove streaks from digital imagery while preserving the sharpness and contrast of the image were designed to remove streaks on single band imagery; not on multi-band imagery. These algorithms only take into account spatial information present in the image to remove streaks. No attempt is made to examine additional color information or spectral correlation available in multi-spectral or hyper-spectral imagery to remove streaks. As a result, when applying these techniques to multi-band imagery, these algorithms do not completely remove all of the color streaks present in the original image and may introduce objectionable color streaks or bands as artifacts. These algorithms do not preserve and/or restore the overall color fidelity of the image. In addition, applying algorithms designed to remove streaks from single band imagery on color or multi-spectral imagery, is a non-optimal method for streak removal for color imagery or multi-spectral imagery, as these algorithms do not use all of the available information that is present in multi-band imagery during the streak removal process.
[0008] U.S. Pat. No. 5,065,444, issued Nov. 12, 1991, to Garber discloses a method of removing streaks from single band digital images by assuming that pixels in a predetermined region are strongly correlated, examining the pixels in the region, computing the difference between the pixels in the region, thresholding the pixel differences lower than a predetermined value, computing a gain and offset value from the distribution of differences, and using the gain and offset value to remove the streaking. Methods that assume a strong correlation between pixels that are near each other, such as the one disclosed by Garber will interpret scene variations as streaks and produce additional streaking artifacts in the image as a result of attempting to remove existing streaks. FIG. 2 a shows an image having streaks 2 and linear features 6 that are in the same direction as the streaks. As shown in FIG. 2 b, the correction of the streaks 2 using the method taught by Garber removes the streaks 2 , but results in additional streaking artifacts 8 . Applying the method by Garber to each spectral band of multi-band images will result in objectionable color streaks and color banding artifacts.
[0009] U.S. Pat. No. 5,881,182, issued Mar. 9, 1999, to Fiete et al., which is incorporated herein by reference, discloses a method of removing streaks by comparing the means between a local window region of two columns of data in the imagery to determine if a streak was present, and presenting statistical methods to calculate a gain and offset to remove the streaks. To apply this method on spectral or color imagery (imagery that consists of more than one spectral band), this method would be applied independently to each band of the spectral imagery, and then the bands of the spectral imagery are recombined to form a color composite image. The method of Fiete et al. looks only at the spatial and luminance information within each band independently; hence calibration differences between each of the bands may not be corrected. As a result, when applied independently to each band of a multi-band image, and then combining these spectral bands together to form a color composite image, all of the color streaks may not be completely removed from the imagery. Yet, when the three spectral bands from a multi-band spectral image, each containing some unremoved streaks and slight banding artifacts, are combined to form a composite three band color image, these artifacts manifest to form objectionable color streaks and color banding in the color composite imagery. The method of Fiete et al. does not adequately remove color streaks from multi-band imagery.
[0010] There is a need therefore for an improved digital image processing method for removing streaks in color or multi-band images. The method presented here is an improvement of the method of Fiete et. al. to better remove color streaks and bands from multi-band imagery.
SUMMARY OF THE INVENTION
[0011] The object of the present invention is achieved in a method of removing columnar streaks from a multi-band digital image of the type in which the spectral bands are transformed to an advantageous spectral space, the streak removal operation is performed in the advantageous spectral space, and then the bands are transformed back into the original space. The method of removing columnar streaks is a method of the type in which it is assumed that pixels in a predetermined region near a given pixel within each transformed band are strongly related to each other and employing gain and offset values to compute streak removal information, by testing for a strong relation between the pixels in a predetermined region near a given pixel and computing streak removal information only if such a strong relationship exists, whereby image content that does not extend the full length of the image in the columnar direction will not be interpreted as a streak.
[0012] The method of the present invention adaptively removes streaking, as well as banding, in multi-band digital images without reducing the sharpness, contrast, or color fidelity of the image. Streaking occurs in multi-band image output from linear scanners and is generally caused by differences in the responsivity of detectors or amplifiers or non-uniform spectral response of filters. The method disclosed detects pixel locations in the image where pixel-to-pixel differences (both within bands and between bands) caused by streaking can be distinguished from normal variations in the scene data. A linear regression is performed between each spatially and spectrally adjacent pixel in a direction perpendicular to the streaking at the detected locations. A statistical outlier analysis is performed on the predicted values to remove the pixels that are not from the streaking. A second linear regression is performed to calculate the slope and offset values. The slope is set to unity if it is not statistically different from unity, and the offset is set to zero if it is not statistically different from zero. The slope and offset values are then used to remove the streaking from the corresponding line of image data.
ADVANTAGEOUS EFFECT OF THE INVENTION
[0013] This invention adaptively removes streaking in multi-band digital image by using both spatial and spectral information within the image. By using spectral information present in multi-band imagery, better determinations can be made of streaks than by using just spatial information present in just one band of the imagery.
[0014] The streak removal operation consists of transforming the multi-band data to an advantageous spectral space, testing for a strong correlation between the pixels in a predetermined region and computing streak removal information only if such a strong relationship exists, and the transforming back into the original spectral space. This process will remove the residual streaks that appear even after a calibration is performed on the imaging sensor. This method does not reduce the contrast, sharpness, and preserves and/or improves the color fidelity of the image.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 illustrates the streaking artifact in an image;
[0016] FIGS. 2 ( a )- 2 ( b ) illustrates the artifacts produced by methods that assume that pixels in a predetermined region near a given pixel are strongly related to each other;
[0017] [0017]FIG. 3 is a diagram showing an image processing chain using the present invention;
[0018] [0018]FIG. 4 illustrates the individual spectral bands that make up a multi-band image;
[0019] [0019]FIG. 5, made up of FIG. 5( a ) and FIG. 5( b ), is a flow chart of the entire multi-band streak removal process according to the present invention
[0020] [0020]FIG. 6 illustrates a digital mask that is used to test for pixels that are strongly related to each other in a predetermined region; and
[0021] [0021]FIG. 7 is a graph illustrating the linear regression with the two adjacent columns of image data, useful in describing the method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The streak removal process of the present invention can be employed in a typical image processing chain, such as the one shown in FIG. 3. A digital sensor 10 , e.g. a linear scanner used in a camera system or a photographic scanner, outputs a multi-band digital image 12 . If the detectors have gone through a calibration process, then each band of the multi-band digital image 12 may go through a detector equalization process 14 to produce an equalized multi-band image 16 . Both the digital image 12 and the equalized image 16 will contain streaks 2 as shown in FIG. 1. The digital multi-band image 12 or the equalized digital multi-band image 16 is processed through the multi-band streak removal process 18 to produce a corrected digital multi-band image 20 that has the streaks removed. This corrected digital image 20 is then processed through the nominal image processing chain and enhancements 22 to produce the final processed image 24 . Without the streak removal process 18 , the image processing and enhancements 22 may actually reduce the quality of the final processed image 24 , especially if the digital image 12 is low in contrast or if the image processing and enhancements 22 includes a feature extraction algorithm, or an automated computer information extraction algorithm.
[0023] If the original image was a photographic color image having streaks or scratches, for example the scratches seen in old movie film, the images may be scanned in a high quality scanner and the streaks or scratches removed by the method of the present invention.
[0024] The preferred embodiment of the multi-band streak removal process described below is presented in the context of removing streaks from a multi-band sensor system. A single-band sensor system collects a single image that represents a single spectral band of the scene. A multi-band sensor system collects a total of N band multiple images, each acquired at different spectral bands denoted (λ 1 , λ 2 , λ 3 , . . . , λ Nband ), as shown in FIG. 4. If the multi-band sensor systems contain more than three spectral bands, then at the completion of the spectral band removal operation, any three of the spectral bands may be selected to create a color composite image for output display. (i.e. mapped to the red, green, and blue channels of an output device) or a subset of the N band images may be selected for input into an automated information extraction algorithm.
[0025] Presented below is the single-band streak removal operation 18 . For the discussion of this invention it will be assumed that the streaks occur in columnar direction of each band of the multi-band digital image 12 . The pixel at column coordinate x and row coordinate y and band location z has a digital count value i(x,y,z). If d x is the detector for column x, then the response curve for detector d x in the digital sensor 10 can be modeled as a linear function of the input illumination radiance, thus
i ( x,y,z )= a x I ( x,y,z )+ b x , (1)
[0026] where I(x,y,z) is the intensity of the illumination radiance at location (x,y,z) in the image, a x is the gain for detector d x , and b x is the bias for detector d x .
[0027] Streaks occur in the digital image 12 because adjacent detectors in the digital sensor 10 have different response curves. The difference Δ(x,y,z) between adjacent pixels within band z is given by
Δ( x,y,z )= i ( x,y,z )− i ( x+ 1 ,y,z )= a x I ( x,y,z )+ b x −a x+1 I ) x+ 1 ,y,z )− b x+1 , (2)
[0028] and is dependent on the detector response as well as the difference between the illumination radiance incident on the adjacent pixels. If the detectors d x and d x+1 have the same response curves, i.e. if a x =a x+1 and b x =b x+1 , then
Δ( x,y,z )= i ( x,y,z )− i ( x+ 1 ,y,z )= a x [I ( x,y,z )− I ( x+ 1, y,z )], (3)
[0029] and the difference between i(x,y,z) and i(x+1,y,z) is proportional to the difference between the illumination radiance incident on the adjacent pixels, which is desired, and no streaks due to sensor calibration errors will be present.
[0030] If I(x,y,z)=I(x+1,y,z) in Eq. (2) then
Δ( x,y,z )= i ( x,y,z )− i ( x+ 1 ,y,z )=[ a x −a x+1 ]I ( x,y,z )+[ b x −b x+1 ], (4)
[0031] and the difference between i(x,y,z) and i(x+1,y,z) is entirely from the different response curves between detectors d x and d x+1 .
[0032] If I(x+1,y,z) is substituted for I(x,y,z) using Eq. (3) then
i ( x , y , z ) = a x i ( x + 1 , y , z ) - b x + 1 a x + 1 + b x = a x a x + 1 i ( x + 1 , y , z ) + [ b x - a x a x + 1 b x + 1 ] . ( 5 )
If Δ a x ≡ a x a x + 1 and Δ b x ≡ b x - a x a x + 1 b x + 1
[0033] then
i ( x,y )=Δ a x i ( x+ 1, y,z )+Δ b x (6)
[0034] and i(x,y,z) is just a linear transformation of i(x+1y,z) with a slope Δa x and offset Δb x . By determining Δa x and Δb x , the streaking between columns x and x+1 can be removed if the pixel count values i(x+1,y,z) are replaced with i(x+1,y,z)where
i ( x+ 1, y,z )≡Δ a x i ( x+ 1 ,y,z )+Δ b x . (7)
[0035] The difference between adjacent pixels is now
Δ( x,y,z )= i ( x,y,z )− î ( x+ 1 ,y,z )= a x I ( x,y,z )+ b x −{Δa x [a x+1 I ( x+ 1 ,y,z )+ b x+1 ]+Δb x } = a x I ( x , y , z ) + b x - { a x a x + 1 [ a x + 1 I ( x + 1 , y , z ) + b x + 1 ] + b x - a x a x + 1 b x - 1 }
= a x [I ( x,y,z )− I ( x+ 1 ,y,z )], ( 8 )
[0036] which is the desired result from Eq. (3), hence no streaks due to sensor calibration error will be present.
[0037] Methods that determine Δa x and Δb x by assuming that the illumination radiance is always approximately equal in a predetermined region near pixel i(x,y,z), e.g. I(x,y,z)≈I(x+1,y,z), such as the one disclosed in U.S. Pat. No. 5,065,444, will generate poor estimates of Δa x and Δb x where I(x,y,z)≠I(x+1,y,z) and artifacts will occur. Methods that determine Δa x and Δb x by testing for strong relationships in spatial features within a single band and computing Δa x and Δb x only from pixels where I(x,y,z)≈I(x+1,y,z), such as the one disclosed in U.S. Pat. No. 5,881,122 do not use any available information present in the other bands. Spectral streaking will not be removed using these methods.
[0038] According to the present invention, spectral streaks will be removed if a spectral transformation is first performed on each imaging band as a pre-processing step to transform the data into a spectrally advantageous space. In general, the spectral transformation will take the form:
i ′( x,y,z ′)=∂[ i ( x,y,z )], (9)
[0039] where ∂ is a transformation operator, operating on each of the spectral bands of the input image, i(x,y,z). In the preferred embodiment, this transformation is a linear combination of the original bands, given by
i ′ ( x , y , z ′ ) = ∑ z = 1 N band α z ′ , z i ( x , y , z ) ( 10 )
[0040] where α z′,z are the linear transformnation coefficients. In matrix notation this transform is given by
ĩ ′( x,y,z ′)= Ãĩ ( x,y,z ) (11)
[0041] where à is the N band ×N band transformation matrix. The transformation combines the radiometric and spectral information from each band into new bands, such that when streaks are removed from the transformed data, the spectral information is included. The optimal transformation to use will be dependent on the number of bands of data, the spectral bandpass of each of the imaging bands, and other imaging band dependent sensor characteristics.
[0042] If the multi-band image contains three bands, or three pre-selected bands from the multi-band image are desired to form a color composite output, then the following transformation is used on the data in the preferred embodiment to minimize color streaking artifacts:
i ′( x,y, 1)=0.2999 i ( x,y, 1)+0.587 i ( x,y, 2)+0.114 i ( x,y, 3) (12)
i ′( x,y, 2)=−0.1687 i ( x,y, 1)−0.3313 i ( x,y, 2)+0.500 i ( x,y, 3) (13)
i ′( x,y, 3)=0.500 i ( x,y, 1)−0.4187 i ( x,y, 2)−0.0813 i ( x,y, 3). (14)
[0043] Once the spectral transformation is performed, a streak removal operation is performed on each of the spectrally transformed bands of i′(x,y,z′) one band at a time using information from the all other spectral bands in the streak removal process. Let i′(x,y,z ref ) refer to the band currently undergoing the streak removal operation, where Z ref is referred to as the reference band. Let i′(x,y,z tests1 ) refer to all other bands in the image, excluding the reference bands (z ref ). These bands shall be referred to as the test bands. In the streak removal operation performed on an individual band, a test is performed for a strong relationship in spatial features between spectrally and spatially correlated pixels and Δa x and Δb x are computed only from those pixels where i′(x,y,z ref )≈i′(x+1y,z ref ) and i′(x,y,z test1d )≈i(x+1,y,z ref ) thus preventing artifacts due to the processing to remove streaking from occurring and allowing spatial information from other bands that are highly correlated to the current band to be used in the streak removal process. A schematic of the streak removal process 18 disclosed in this invention is shown in FIG. 5. First two adjacent columns of image data are selected 30 from band z ref . Next, a column of pixel value pairs representing the pixel values of the adjacent pixels of the two columns is formed 32 . Next a pair of columns of local mean values representing the mean values of pixels in an N pixel window for each of the adjacent columns of image data is formed 34 . The local means μ ref (x,y,z ref ) and μ ref (x+1,y,z ref ) are calculated using
μ ref ( x , y , z ref ) = 1 N ∑ n = - ( N - 1 ) 2 ( N - 1 ) 2 i ′ ( x , y + n , z ref ) ( 15 ) μ ref ( x + 1 , y , z ref ) = 1 N ∑ n = - ( N - 1 ) 2 ( N - 1 ) 2 i ′ ( x + 1 , y + n , z ref ) ( 16 ) μ test i ( x , y , z test i ) = 1 N ∑ n = - ( N - 1 ) 2 ( N - 1 ) 2 i ′ ( x , y + n , z test i ) ( 17 )
[0044] where N is the window length. To determine if i′(x,y,z ref )≈i′(x+1,y,z ref ), a mask, such as the mask 35 shown in FIG. 6, is centered at pixel i′(x,y,z ref ) and convolved with the image. Pixels in the first and last (N−1)/2 rows of the image will not be used to determine Δa x and Δb x .
[0045] Next, a test for similarity between bands in the local pixel regions is also performed. First a bias, B 1 , is added to the pixel values in each of the local windows in the bands z test1 used to calculate the mean in Eq. (17) such that μ ref =μ test1 . Next, a correlation is calculated 36 over the local window region (x,y+n) between each test band z testi and the reference band z ref, given by
Corr i = ∑ n [ i ′ ( x , y + n , z ref ) - μ ref ] * [ i ′ ( x , y + n , z testi ) - μ testi ] ∑ n [ i ′ ( x , y + n , z ref ) - μ ref ] 2 ∑ n [ i ′ ( x , y + n , z testi ) - μ testi ] ( 18 )
[0046] Next, a local difference metric M ref (x,y,z ref )is calculated that measures the similarity between local pixel regions. A difference metric based on the difference between the mean reduced values is given by
M ref ( x , y , z ref ) = 1 N ∑ n = - ( N - 1 ) 2 ( N - 1 ) 2 { [ i ′ ( x , y + n , z ref ) - μ ( x , y , z ref ) ] - [ i ′ ( x + 1 , y + n , z ref ) - μ ( x + 1 , y , z ref ) ] } 2 ( 19 )
[0047] If the calculated correlation, Corr i >T c , where T c is the correlation threshold, for a given test band (Z testi ), then an additional difference metric M testi (x,y,z testi ) is calculated:
M testi ( x,y,z testi )= M testi ( x , y , z testi ) = 1 N ∑ n = - ( N - 1 ) 2 ( N - 1 ) 2 { [ i bias ′ ( x , y + n , z testi ) - μ testi ( x , y , z testi ) ] - [ i ′ ( x + 1 , y + n , z ref ) - μ testi ( x + 1 , y , z ref ) ] } 2 ( 20 )
( 20 )
[0048] where i bias (x,y+n,z testi ) represents the bias adjusted pixels over the local window region. Next, the average local difference metric 37 is calculated:
M ( x , y , z ) = M ref ( x , y , z ref ) + ∑ test i M test i ( x , y , z test i ) N bandsC + 1 ( 21 )
[0049] where N bandsC are the number of test bands in which Corr i >T c .
[0050] The local pixel regions are similar if M(x,y,z)<T M , where T M is the difference metric threshold. The optimal value for T M will depend on the characteristics of the digital sensor 10 . A maximum difference threshold, T 66 , is defined by determining the largest magnitude difference of Δ(x,y,z) that is possible from calibration differences alone.
[0051] To determined the values of Δa x and Δb x in Eq. (7), two columns of pixel values i x,z (n) and pixel values i x+1 (n), where n is a counting index, are generated 38 for each row x, where only the k values of i(x,y,z ref ) and i(x+1,y,z ref ) that satisfy the conditions M(x,y,z ref )<T M and |Δ(x,y,z ref )|<T Δ are used.
[0052] Initial estimates of the slope and offset are determined by performing a linear regression between i x (n) and i x+1 (n) to determine the regression line 39 in FIG. 7. The initial estimate of the slope, Δa′ x , is calculated 40 by
Δ a x ′ = k ∑ n = 1 k i x + 1 ( n ) i x ( n ) - ∑ n = 1 k i x + 1 ( n ) ∑ n = 1 k i x ( n ) ) k ∑ n = 1 k i x + 1 2 ( n ) - ( ∑ n = 1 k i x + 1 ( n ) ) 2 ( 22 )
[0053] where k is the total number of elements in i x (n). The initial estimate of the offset, Δb′ x , is calculated 42 by
Δ b x ′ = ∑ n = 1 k i x ( n ) - Δ a x ∑ n = 1 k i x + 1 ( n ) k . ( 23 )
[0054] The slope Δa x and offset Δb x for Eq. (7) are determined by performing a second linear regression between i x (n) and i x+1 (n) after the statistical outliers 43 in FIG. 7 have been removed from the estimates of Δa′ x and Δb′ x . The standard error s e of the linear regression is calculated 44 . The statistical outliers 43 will be defined as points lying outside a boundary 45 that is dependent on the standard error of estimate S e , given by
s e = ∑ n = 1 k [ i x ( n ) - i ^ x ( n ) ] 2 k - 2 , ( 24 )
[0055] where
î x ( n )=Δ a x i x+1 ( n )+ Δb x . (25)
[0056] Values of i(x,y,z ref ) that satisfy the condition |i x (n)−î x (n)|>T s are determined 56 , these values are not statistical outliers. The outlier threshold T s is proportional to s e and is typically set equal to 3s e . Two new columns of pixel values, i x (n) and its adjacent pixel i x+1 (n) are generated 48 for each row x, where only the j≦k. The slope Δa x and offset Δb x for Eq. (7) are now determined 60 by
Δ a x = j ∑ n = 1 j i x + 1 ( n ) i x ( n ) - ∑ n = 1 j i x + 1 ( n ) ∑ n = 1 j i x ( n ) ) j ∑ n = 1 j i x + 1 2 ( n ) - ( ∑ n = 1 j i x + 1 ( n ) ) 2 ( 26 ) Δ b x = ∑ n = 1 j i x ( n ) - Δ a x ∑ n = 1 j i x + 1 ( n ) j . ( 27 )
[0057] The final statistical tests performed 52 are to determine if the slope Δa x is statistically different from unity and the offset Δb x is statistically different from zero. These tests are performed to ensure that the difference in the response curves estimated for detectors d x and d x+1 are statistically different. If they are not statistically different, then using the estimates for Δa x ≠1 and Δb x ≠0 may add streaking to the image rather than remove it, hence degrading the quality of the image rather than improving it.
[0058] A statistical hypothesis test is used to determine if the slope Δa x is statistically different from unity. The t statistic is given by
t Δa x = Δ a x - 1 s s i ( 28 )
[0059] where
s = { ∑ n = 1 j i x 2 ( n ) - [ ∑ n = 1 j i x ( n ) ] 2 j } - Δ a x { ∑ n = 1 j i x + 1 ( n ) i x ( n ) - ∑ n = 1 j i x + 1 ( n ) ∑ n = 1 j i x ( n ) j } ( 29 ) s i = ∑ n = 1 j i x + 1 2 ( n ) - [ ∑ n = 1 j i x + 1 ( n ) ] 2 j . ( 30 )
[0060] The t statistic is compared to the t distribution value t α/2 to determine if Δa x is statistically different from unity. If t Δa x <t α/2 then Δa x is not statistically different from unity hence a value of 1 is used 54 for Δa x in Eq. (7). The value used for t α/2 depends on the number of sample points j as well as the confidence level desired for the statistical test, which is given by 100(1−α)%. For a 95% confidence and
j > 50 , t α 2 = 1.96 .
[0061] To determine if the offset Δb x is statistically different from zero, the t statistic is given by
t Δb x = Δ b x s ∑ n = 1 j i x + 1 2 ( n ) j s i . ( 31 )
[0062] If t Δb x <t α/2 then Δb x is not statistically different from zero hence a value of 0 is used 56 for Δb x in Eq. (7).
[0063] Finally, the pixels i(x+1,y,z ref ) in column x are modified by Eq. (7) to remove the streaks 58 . The procedure outlined above is repeated for the next column of image data. This process is continued until all columns of the image data have been processed in the reference band. This process is then repeated for each band of the spectrally transformed image. Once each band of the spectrally transformed image is streak-removed, the inverse spectral transformation 60 is applied
ĩ ( x,y,z )= Ã −1 ĩ ′( x,y,z ′) (32)
[0064] where à −1 is the N band ×N band inverse transformation matrix, and the corrected digital image 24 is output. In the preferred embodiment for a three-band color image, the inverse spectral transform is:
i ( x,y, 1)= i ′( x,y, 1)+1.402 i ′( x,y, 3) (33)
i ( x,y, 2)= i ′( x,y, 1)−0.34414 i ′( x,y, 2)−0.71414 i ′( x,y, 3) (34)
i ( x,y, 3)= i ′( x,y, 1)+1.772 i ′( x,y, 2). (35)
[0065] The invention has been described with reference to a preferred embodiment. However, it will be appreciated that variations and modifications can be effected by a person of ordinary skill in the art without departing from the scope of the invention.
PARTS LIST
[0066] [0066] 2 streaks
[0067] [0067] 4 banding
[0068] [0068] 6 scene variation
[0069] [0069] 8 image artifact
[0070] [0070] 10 digital sensor
[0071] [0071] 12 digital image
[0072] [0072] 14 detector equalization
[0073] [0073] 16 equalized image
[0074] [0074] 18 streak removal operation
[0075] [0075] 20 corrected digital image
[0076] [0076] 22 image processing and enhancements
[0077] [0077] 24 final processed image
[0078] [0078] 28 transform multi-band data to spectrally advantageous space step
[0079] [0079] 30 selecting two adjacent columns of pixels step
[0080] [0080] 32 create two columns of adjacent pixel values step
[0081] [0081] 34 calculate local means step
[0082] [0082] 35 mask used for testing pixel relationship
[0083] [0083] 36 Calculate correlation between bands step
[0084] [0084] 37 calculate local difference metric step
[0085] [0085] 38 remove pixel values from columns of pixel values that exceed thresholds step
[0086] [0086] 39 line from linear regression
[0087] [0087] 40 determine initial estimate of slope step
[0088] [0088] 42 determine initial estimate of offset step
[0089] [0089] 43 statistical outliers
[0090] [0090] 44 calculate standard error of linear regression step
[0091] [0091] 45 statistical outlier boundary
[0092] [0092] 46 determine statistical outliers step
[0093] [0093] 48 remove statistical outliers from columns of pixel values step
[0094] [0094] 50 determine new estimate of slope and offset step
[0095] [0095] 52 determine t statistics for slope and offset step
[0096] [0096] 54 set slope to unity if not statistically different from unity step
[0097] [0097] 56 set offset to zero if not statistically different from zero step
[0098] [0098] 58 remove streaking using slope and offset values step | A method of removing streaks from multi-band digital images is presented in which a multi-band image is transformed to an advantageous spectral space, in which a streak removal operation is applied to the image in the advantageous spectral space. The streak removal operation is a method of removing columnar streaks from a multi-band digital image of the type in which it is assumed that pixels in a predetermined spatial and spectral region near a given pixel are strongly related to each other and employing gain and offset values to compute streak removal information, a test is performed for a strong relation between the pixels in a predetermined region spatially and spectrally near a given pixel and streak removal information is computed only if such a strong relationship exists, whereby image content that does not extend the full length of the image in the column direction will not be interpreted as a streak. | 6 |
RELATED APPLICATIONS
[0001] The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/093,916 filed on Sep. 3, 2008 and titled Modular Pulsed Pressure Device for the Transport of Liquid Cryogen to a Cryoprobe, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the medical technology field and, in particular, to a medical device for use in a cryogenic system.
BACKGROUND OF THE INVENTION
[0003] Over a recent number of years, there has been a strong movement within the surgical community toward minimally invasive therapies. The main goals of the minimally invasive therapies include: 1) eradication of targeted tissue, 2) decreased hospitalization time, 3) limited postoperative morbidities, 4) shortened return interval to daily functions and work, and 5) reduced overall treatment cost. Cryotherapy is a minimally invasive method of treating a disease state through tissue freezing with thousands of patients now receiving the procedure annually. Currently, cryotherapy is used to treat numerous disease states including organ confined tumors such as prostate, kidney, liver, as well as cardiovascular disease, retinal detachment, pain management, and other illness/disease states.
[0004] Cryotherapy is an effective yet minimally invasive alternative to radical surgery and radiation therapy. The procedure is done under either general or epidural anesthesia. Since it is minimally invasive, it offers patients a quicker recovery and reduced severity of potential side effects. Without the expense associated with major surgery or an extended hospital stay, cryotherapy is a cost-effective treatment option.
[0005] The approaches utilized to date have focused on the delivery of liquid cryogen through the use of moderate to high pressure on the entire system or piston/bellows compression to drive fluid movement. At present, current systems utilizing liquid nitrogen operate at pressures between 14-480 psi; the systems in use cannot operate or withstand pressures greater that 500 psi. Further, the use of heat exchangers have been limited to coils placed into a bath of cryogen to allow for time consuming, inefficient passive subcooling of the cryogen in which activation of these devices circulate a cryogen (such as liquid nitrogen) to a probe to create a heat sink, thus resulting in tissue freezing.
[0006] There exists a need for improvements in cryotherapy, and medical devices or components associated with the treatment, to better circulate liquid cryogen to a cryoprobe, to provide for rapid delivery through small tubes, and to facilitate improved measures for treatment and cost. The medical device of the present invention will allow for the circulation (cooling, delivery, and return) of liquid cryogen to a cryoprobe for the freezing of targeted tissue. The invention will facilitate the eradication of tissue, decrease hospitalization time, limit postoperative morbidities, shorten return to daily functions and work, and further reduce the overall treatment cost. Desirably, these improvements to device design and application will also increase its utilization for the treatment of multiple disease states.
SUMMARY OF THE INVENTION
[0007] The following invention is a cryogenic medical device designed to deliver subcooled liquid cryogen to various configurations of cryoprobes for the treatment of damaged, diseased, cancerous or other unwanted tissues. The device is a closed or semi-closed system in which the liquid cryogen is contained in both the supply and return stages.
[0008] By converting liquid nitrogen to supercritical nitrogen (SCN) in a cylinder/cartridge cooled by atmospheric liquid nitrogen (−196° C.), the SCN can be subcooled and tuned to the liquid phase, attaining an excess temperature. When the SCN is injected into one or more flexible cryoprobes, the SCN flows with minimal friction to the tip of the probe. In the tip, SCN pressure drops due to an increased volume and outflow restriction, heat is absorbed (nucleate boiling) along the inner surface of the tip, micro bubbles of nitrogen gas condense back into a liquid, and the warmed SCN reverts to pressurized liquid nitrogen as it exits the return tube and resupplies the dewar containing atmospheric liquid nitrogen. This flow dynamic occurs within a few seconds, typically in the order of 1 to 10 seconds depending on the probe or attachment configuration, and is regulated by a high pressure solenoid valve. Further, the cryosurgical procedure once instruments are in place can be performed with freeze times in ranges of about 15 seconds to 5 minutes (or ranges thereof), a drastic improvement over current known methods. (Therefore, consecutive freeze times over the course of the entire procedure significantly reduces time within the medical care setting, reducing overall health costs.) Upon emptying of the first cartridge subassembly, the process can be repeated with the second cartridge subassembly or any number of cartridges operated individually or in combination. Furthermore, embodiments of the present invention can be incorporated in any supercooling system or in delivering liquid cryogen to the desired instrument.
[0009] In one embodiment, the closed or semi-closed system has multiple pressurized cylinders filling and firing in sequence, and pressurized through a heating coil in one or more of the contained pressurized cylinders. The device is vented to the surrounding atmosphere through an adjustable pressure vent to prevent excess pressure buildup while in operation. The device comprises a number of parts including a vacuum insulated outer dewar, submersible cryogen pump, a series of self-pressurizing pulsatile delivery chambers, baffled linear heat exchanger, return chamber, and a series of valves to control the flow of the liquid cryogen. The outer dewar comprises a cryogenic apparatus having pressurizing pulsatile delivery chambers which drive liquid cryogen through the baffled linear heat exchanger. The linear heat exchanger comprises a tube-within-a-tube (i.e. chamber within a chamber configuration) whereby a vacuum is applied to the outer chamber to subcool an isolated reservoir of liquid cryogen. The inner chamber comprises a series of baffles and a central spiral to increase the flow path of the liquid cryogen while providing for increased contact-based surface area with the outer chamber to allow for more effective heat transfer and subcooling of the cryogen being delivered to the probe. Following circulation to the cryoprobe, cryogen (liquid and gas) is returned to the device into a return chamber which surrounds the supply chamber, thereby providing for a staged secondary subcooling chamber for the cryogen in the supply tube. The return chamber is open to the main dewar tank thereby allowing for exchange of liquid and gas between the supply and return chambers. Device operation is controlled and monitored by a series of pressure and vacuum valves designed to control the flow, cooling, and pressurization of the liquid cryogen. This control is achieved through various configurations of manual and computer controlled systems.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The invention is best understood from the following detailed description when read with the accompanying drawing figures. It is emphasized that the various features are not necessarily drawn to scale. In fact, the dimensions may be arbitrarily increased or decreased for clarity of discussion.
[0011] FIG. 1 is a side view of an illustrative embodiment of the device of the present invention.
[0012] FIG. 2A is a side view of one embodiment of a heat exchanger of the present invention.
[0013] FIG. 2B is a cross-sectional view of FIG. 2A , a front view of one embodiment of a device of the present invention.
[0014] FIG. 3A illustrates a side view of one embodiment of a heat exchanger of the present invention.
[0015] FIG. 3B is a cross-sectional view of FIG. 3A , one aspect of fluid flow through one embodiment of a heat exchanger of the device.
[0016] FIG. 4 is a top view of one embodiment of a device of the invention.
[0017] FIG. 5 is a depiction of a front view of the system.
DETAILED DESCRIPTION
[0018] In the following detailed description, for purposes of explanation and not limitation, exemplary embodiments disclosing specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one having ordinary skill in the art that the present invention may be practiced in other embodiments that depart from the specific details disclosed herein. In other instances, detailed descriptions of well-known devices and methods may be omitted so as not to obscure the description of the present invention.
[0019] An external view of a device and system in accordance with one embodiment of the present invention is shown in FIG. 1 . The cryogenic system or device 30 has sidewalls 17 which form a container 6 that encloses an internal cavity, or lumen 15 . In an embodiment of FIG. 1 , the container 6 takes the form of a vacuum insulated dewar 6 . The dewar 6 stores liquid cryogen and interconnects a supply line II and return line 12 to a probe or catheter (not shown) to form a closed system 30 . The dewar 6 may be made of material such as stainless steel or any other material known for providing a vacuum insulated vessel. The dewar 6 is filled with liquid nitrogen or other liquefied gas (here, discussing as cryogen) to a maximum level 13 . In one aspect, liquid nitrogen may be preferred. In another aspect, any fluidic cryogen may be utilized (e.g. argon, oxygen, helium, hydrogen).
[0020] Within the internal cavity 15 of the dewar 6 is a submersible pump 1 which delivers the liquid cryogen to a sealed pressurization apparatus 40 . In one embodiment, a valve 2 controls the pressure fill into internal open chamber 42 of the pressurization apparatus 40 . Once the cryogen enters the pressurization apparatus 40 , an immersion heater 44 housed in the internal open chamber 42 heats the cryogen to create a desired pressure. The liquid nitrogen within the pressurized chamber starts at a temperature of about −196° C. When the heater is activated, it boils the nitrogen within the immediate area. Temperature within internal cavity 42 therefore stays within about −196° C. to −150° C., more typically in the range of about −196° C. to −160° C., or rather between about −170° C. to −161° C. Pressurized cryogen is then released through a valve 32 into the baffled linear heat exchanger 4 . In one aspect, liquid nitrogen is converted to supercritical nitrogen (SCN) within the pressurization apparatus. The SCN is then directed to the heat exchanger for subcooling and tuned to the liquid phase to attain an excess temperature. Thereafter, the SCN can be injected into one or more flexible cryoprobes such that the SCN flows with minimal friction to the tip of the probe.
[0021] The baffled linear heat exchanger 4 in one embodiment is surrounded by a subcooling chamber 3 which subcools the pressurized cryogen for delivery to external cryoprobes. The subcooling chamber 3 in connection with the heat exchanger 4 at an entrance 23 and an exit opening 36 form an integral unit 51 for supplying subcooled liquid cryogen. From the heat exchanger 4 , the subcooled cryogen passes into a supply line 11 and continues out through an exit port 35 and through a control valve 14 where various configurations of cryoprobes are attached. The subcooling chamber may attach a vent line to any of the vents 8 , to a supply connecting line 19 controlled through a valve 27 , or to a vacuum line 16 through a control valve 7 which is connected to a vacuum pump 18 .
[0022] The cryogen is returned (as demonstrated by the arrows in FIG. 1 ) from the cryoprobe via a return tube 12 into a return chamber/cylinder 5 of the dewar 6 . The return tube 12 connects into the return cylinder 5 which also surrounds the supply tube 11 that exits the heat exchanger 4 . One or more exit ports 35 may be included in a side wall 17 of the dewar 6 or may be a separate unit 14 to incorporate various control valves.
[0023] In operation, the device 30 is filled through a supply port 29 and then sealed to form a closed system, thereby allowing for the supply, return, collection, and re-utilization of liquid cryogen during its utilization in the medical/surgical field. The entire system 30 may or may not be pressurized during operation. The system may also be vented to the surrounding environment to prevent excess pressure buildup during operation. In one aspect, the returning cryogen empties into the return cylinder or chamber 5 . In another aspect, the returning cryogen may empty as bulk fluid into the internal lumen 15 within the dewar 6 .
[0024] In one embodiment of the present invention, the linear heat exchanger 4 subcools the liquid cryogen prior to delivery to tissue. In the embodiment of FIG. 1 , the linear heat exchanger 4 is an inner chamber 4 which passes through subcooling chamber 3 and is connected via the entrance 23 and exit opening 36 . Liquid cryogen passing through the inner chamber 4 is reduced in temperature to a subcooling degree by the outer subcooling chamber 3 . The chamber within a chamber configuration includes a subcooling vacuum chamber 3 filled with liquid cryogen upon which a vacuum 18 is drawn through valve-controlled port 9 to reduce the atmospheric pressure on the cryogen. The temperature of the cryogen within the subcooling chamber 3 can then be reduced even further. The subcooling chamber 3 also comprises valve controlled ports 8 external to the maximum liquid cryogen level for monitoring and electronically controlling temperatures, pressures, and flow rates of liquid cryogen passing through the subcooling unit. In one aspect, a vacuum 18 can be drawn on vacuum line 16 at a controlled internal valve 7 or external valve 9 . In another aspect, valve controlled ports 8 may be accessible for delivery of liquid cryogen to the subcooling chamber 3 by way of a supply line 19 or as a vent 8 for any excessive gas coming from the subcooling chamber 3 . As depicted in FIG. 1 , the vacuum 18 also is attached to the cryoprobe(s) by way of vacuum line 39 .
[0025] Aspects of the linear heat exchanger 4 are illustrated in FIGS. 2A , 2 B and FIGS. 3A , 3 B. FIG. 2A and FIG. 3A illustrate side views of different aspects of a linear baffled heat exchanger 4 and subcooling unit 3 as an integral unit 51 . FIG. 2B depicts a cross-section of FIG. 2A ; FIG. 2B is a front view of the linear baffled heat exchanger 4 when looking into the inner chamber 4 . An interior central component or spiral 20 within the interior lumen of the chamber 4 operates like a corkscrew to increase the flow path 25 of the liquid cryogen. An outer wall 22 of the inner chamber 4 also comprises baffles 24 which increase the surface area in the heat exchanger for quicker and reduced cooling of the liquid cryogen. As illustrated, a series of baffles 24 emanate into the flow path 25 (as illustrated by arrows) of the cryogen in the inner lumen, thereby increasing the surface area in the heat exchanger 4 . The spiral component, however, may be any size and shape as to efficiently increase the flow of liquid cryogen. Planar structures, as described below, or any additional features included to increase surface area may be incorporated or substituted.
[0026] FIG. 3A illustrates another embodiment of a linear heat exchanger 4 such that the internal structure 20 has a planar configuration and also operates in a circular motion to increase the flow 25 of the liquid cryogen. FIG. 3B depicts a cross-section of FIG. 3A such that the inner tubular unit 21 assists the internal structure 20 in circulating the flow of liquid cryogen through the interior lumen of the chamber 4 .
[0027] One embodiment of the medical device comprises a return chamber 5 which is illustrated as a return cylinder 5 in FIG. 1 such that the return chamber 5 surrounds the supply line 11 coming from the heat exchanger 4 . The return chamber 5 and the surrounded supply line may then provide a secondary heat exchanger for the system/medical device 30 . Cryogen return is vented into the return chamber 5 . In one aspect, the return chamber 5 comprises a series of vent holes 26 near the top of the return chamber 5 to allow for the venting of gas and/or liquid overflow into the main dewar 6 . Vent holes 26 allow for the reutilization of cryogen and thus extend the operation time for the medical device 30 .
[0028] In another aspect, the return tube 12 is vented into the main dewar 6 either directly or by first passing through a linear heat exchanger (similar to the combination of heat exchanger 4 and subcooling chamber 3 ) to subcool the return cryogen prior to venting into the main dewar 6 . Return of the cryogen to the main dewar 6 allows the cryogen to return through a heat exchanger such that the cryogen is reutilized and extends the operation time even longer.
[0029] In another embodiment, the medical device 30 may provide a system which is controlled through a series of computer controlled valves including any heaters, sensors, motors, or gauges. The sensors control and monitor pressure, temperature, and fluid level in the dewar, and can measure any metric as may be desired. In one aspect, the sensors monitor pressure levels within defined safety ranges. In another aspect, the sensors may control the pressurization of one or more components internal to the dewar. Any of the valves 2 , 7 , 8 , 9 , 27 or 32 including exit portal valve 14 , may be automated to enable a controlled and consistent operation of the cryogenic system (e.g. computer controlled operation through the electronically controlled valves).
[0030] An embodiment of a system 50 is shown in FIG. 4 . As illustrated in a top view of the system 50 , a series of six pulsatile pressurization chambers 40 are sealed chambers/cylinders 40 within dewar 6 of the closed system 50 . From the pump, liquid cryogen in pumped to the pulsatile pressurization chambers 40 which then delivers liquid cryogen in a continuous series of bursts to the heat exchanger 4 . The baffled linear heat exchanger 4 provides an enhanced subcooling of the pressurized liquid cryogen while also incorporating an integral subcooling unit 3 . The chambers 40 , each comprising an individual immersion heater 44 , can then sequentially deliver liquid cryogen at consistent rates, or as specifically determined rates, to the heat exchanger 4 .
[0031] From the heat exchanger, the subcooled cryogen passes into a supply line 11 and continues out through an exit port 35 where a control valve 14 is positioned and various configurations of cryoprobes are attached. The cryogen is returned (as demonstrated by the arrows in FIG. 4 ) via a return tube 12 from the cryoprobe to the dewar 6 into a return cylinder 5 . The return tube 12 connects into the return cylinder which surrounds the supply tube 11 that exits the heat exchanger 4 . The entire system 50 may or may not be pressurized during operation. The device is also vented through vent ports 8 to the surrounding environment to prevent excess pressure buildup during operation.
[0032] During the operation of the system 50 , as illustrated in the embodiment of FIG. 4 , a cryogenic system 50 has been filled and detached from its cryogenic fill tank. In one embodiment, the system 50 is a separate mobile unit protected and contained entirely within an enclosed console for easy access and mobility. Once the system has been sealed, the cryogenic supply can be maintained for several procedures. The reutilization of the liquid cryogen provides a time savings and cost-efficient model for cryotherapeutic and cryosurgical procedures. The system 50 can be further utilized for any process requiring rapid cooling.
[0033] As depicted, the system 50 comprises a submersible liquid nitrogen pump 1 connected to a supply line 11 which directs the liquid nitrogen into a supply manifold 33 . The supply manifold 33 routes the liquid nitrogen into at least one pulsatile pressurization chamber 40 where the liquid cryogen is heated. The pressurized liquid cryogen, here, liquid nitrogen, then starts filling the next pressurization cylinder/chamber 40 in the series such that when one chamber 40 is filling, another can be simultaneously pressurized and prepared for use. This permits a wave of activity through the cylinders so that it can cycle through each step of system operation. As the pressurized cryogen is delivered to the heat exchanger 4 , and passes the subcooled pressurized cryogen out through the supply line 11 through the exit port 35 and into the attached cryoprobes, another pressurization chamber is filled and pressurized. The simultaneous use and pressurization of the liquid cryogen provides for the sequential delivery of liquid cryogen in a continuous series of pulsations to a cryogenic instrument or probe.
[0034] In one embodiment, liquid nitrogen is used; however, any cryogenic fluid may be utilized, including nitrogen, argon, helium, hydrogen, and other such desired fluids. Each pressurization apparatus 40 comprises a pressure valve controlled inlet 52 , valve controlled outlet 54 , and vent ports as may be desired, as well as an immersion heater 44 . In one aspect, the filling of the pressurization apparati 40 is controlled through a series of pressure valves 52 on the supply manifold 33 . Liquid cryogen is heated within each pressurized apparatus. Pressurized liquid cryogen is then released through the control valve 54 to an outlet port/opening 46 of an outlet manifold 34 to the supply line 11 , and delivered to a baffled linear heat exchanger 4 . In the illustrated embodiment, a subcooling unit 3 surrounds the heat exchanger 4 for more rapid cooling.
[0035] In one embodiment, the cryogenic device 50 comprises six pressurized apparati 40 linked together. Other embodiments, however, may comprise any number of pressurized apparati 40 individually or linked together in combination. The apparati can then be controlled individually or in sequence to deliver pressurized liquid cryogen to the heat exchanger 4 . In another aspect, one or more pressurization apparati 40 may be arranged to supply one or more cryoprobes. Further, the series of pressurized apparati 40 may be interconnected with another series of apparati 40 .
[0036] In one embodiment of FIG. 4 , six pulsatile pressurization chambers 40 are housed within a support network of a console. In one example, three of the cylinders within one-half of the dewar simultaneously fill while three cylinders within the other half of the dewar deliver cryogen out through the outlet manifold. (Any number of cylinders, however, may be operated individually or in desirable combinations.) Liquid cryogen is heated in the sealed pressurization chambers 40 . Pressure is increased to a specified level in the sealed pressurization chambers 40 , and then the pressurized cryogen is controllably released into a heat exchanger 4 to subcool the cryogen. In one aspect, a subcooling vacuum chamber 3 surrounds the heat exchanger 4 , facilitating the delivery of subcooled cryogen to an attached cryoprobe (also referred to as probe or catheter). As the pressurized cryogen is utilized, a sensor within the heat exchanger monitors the temperature and pressure of the subcooled cryogen passing into supply line II as it continues out through an exit port 35 where various configurations of cryoprobes are attached.
[0037] Although the system may fill or discharge each cylinder 40 individually, any simultaneous fill or discharge, or rate of fill or discharge, may be incorporated into the system. The closed system keeps a constant supply of liquid nitrogen available for delivery to the cryoprobe and provides a more immediate and rapid rate of cooling for cryotherapeutic procedures. It is therefore possible to close the supply port 29 where supply tanks fill the dewar (See FIG. 1 and FIG. 4 ) and move the system to any locale or setting. Furthermore, as depicted in FIG. 1 , the supply valve 2 may be closed and the release valve 14 opened to create a flow of liquid cryogen to the cryoprobe. Various arrangements of valves and sensors may therefore provide for similar flow.
[0038] In one embodiment, the pressurized chambers 40 are filled and the dewar sealed. A single drive pump 1 perpetuates directional flow of the cryogen into the pressurization chambers. In one embodiment, all chambers can be filled through various configurations of single direction pumping. In another embodiment, a reversible pump and fill method allows one pressurized chamber 40 to fill and then the pump 1 flips or reverses functionality to fill another pressurized chamber. This process can be repeated to fill any number of chambers.
[0039] In one embodiment, pressurized chambers 40 are enclosed completely within the dewar 6 . However, any arrangement of the pressurized cylinders is possible so long as the closed system provides for the pulsatile delivery of cryogen to the cryoprobe. As such, any single or multiple configurations of cryoprobes or catheters may be used. Such instruments may also include cryoguns or cryodevices for rapid cryo-delivery processes or cryotherapies.
[0040] As illustrated in FIG. 5 , a cryogenic system 60 (also known as cryoengine 60 ) has a two cylinder configuration, the system of which is divided into two subassemblies: (I) those components above the cover 61 and (H) those components below the cover. All of the components below the cover are contained in a liquid nitrogen dewar and immersed in liquid nitrogen at atmospheric pressure (BP=−196° C.) during operation. To understand the operational features of the cryoengine and method of production and transport of supercritical nitrogen (SCN), a brief description of cryogen flow follows.
[0041] Upon filling the dewar (not pictured) with liquid nitrogen from an external source, an immersible liquid cryogen pump 1 is activated to fill each cryogen supply cylinder 2 a & 2 b , or cartridge, sequentially. Initially, one cartridge 2 a is filled along with its linked cryogen pressurization cartridge 3 a . Cryogenic solenoid valves 4 provide venting of the gas within the cartridge assembly to support filling. Upon completion of the filling process, the cryogen pressurization cartridge 3 a is heated to generate a pressure of about 1000 psi (68 bar). Liquid nitrogen becomes critical at about 493 psi (34 bar) (BP=−147° C.). Pressurization beyond the critical point results in the formation of SCN, a dense fluid without surface tension and capable of frictionless flow, and has properties that may be tuned to either a gas or liquid.
[0042] By converting liquid nitrogen to SCN in a cartridge cooled by atmospheric liquid nitrogen (−196° C.), the SCN is subcooled and tuned to the liquid phase, attaining an excess temperature (i.e. the ability to absorb heat without boiling) of approximately 50° C. When the SCN is injected into the flexible cryoprobe, the SCN flows with minimal friction to the tip of the probe (boiling chamber). In the tip, SCN pressure drops due to an increased volume and outflow restriction, heat is absorbed (nucleate boiling) along the inner surface of the TIP, micro bubbles of nitrogen gas condense back into a liquid, and the warmed SCN reverts to pressurized liquid nitrogen as it exits the return tube and resupplies the dewar containing atmospheric liquid nitrogen. This flow dynamic occurs within a few seconds and is regulated by a high pressure solenoid valve 4 . Upon emptying of the first cartridge subassembly ( 2 a & 3 a ), the process is repeated with the second cartridge subassembly ( 2 b & 3 b ).
[0043] As demonstrated by FIG. 5 , the limitations of liquid nitrogen have been overcome by developing a novel device to convert atmospheric liquid nitrogen to supercritical nitrogen. Where liquid nitrogen was previously delivered through large tubes and did not provide for rapid delivery, the current system herein described allows for rapid delivery of liquid cryogens through very small tubing. The SCN can be injected or drawn through two plus meters of hypodermic tubing without boiling, thereby resulting in near instantaneous ice formation at the tip to target site specific ablation of tissue as well as the creation of transmural lesions without the formation of a thrombus or aneurysm. Supercritical nitrogen is a dense fluid with properties of both gas and liquid that can be tuned toward one phase or the other. In the liquid phase, SCN lacks surface tension and transports without friction. The above-described technology generates SCN in a pressurized cartridge immersed in atmospheric liquid nitrogen. This cryoengine, which operates as a cryogen generator, produces SCN in the liquid phase with a boiling point of about −149° C. which is subcooled by the surrounding atmospheric liquid nitrogen to about −196° C. When the SCN is expelled from the device to the probe tip, the SCN passes instantly through the system without the phase transition to a gas due to both the frictionless flow and the subcooling which compensates for parasitic heat gain along the path. As such, the embodiment of FIG. 5 may be utilized in any supercooling system or in directing flow of liquid cryogen through to a cryo-instrument. The supercritical point will be determined by the chemistry of the specified liquid or gas used. Therefore, the system can be adjusted to accommodate for differences in chemistry.
[0044] In utilizing the medical device of the present invention, various methods in the industry may be employed in accordance with accepted cryogenic applications. As discussed, the embodiments of the present invention are for exemplary purposes only and not limitation. Advantageously, this device represents an important step in targeted thermal therapies. Various cryosurgical devices and procedures to apply freezing temperatures to a target tissue may be employed for use with the medical device of the present invention. The medical device of the present invention has been developed to enable and improve some of the approaches used to target or ablate tissue. Furthermore, the medical device can couple controlled pumping of a liquid cryogen through a baffled linear heat exchanger to decrease the overall temperature of the cryogen providing a greater heat capacity of the fluid and thereby resulting in an increased cooling potential in a cryoprobe.
[0045] Thus, the invention facilitates other improvements in cryotherapy, and medical devices or components associated with the treatment. The medical device of the invention allows for the circulation (cooling, delivery, and return) of liquid cryogen to a cryoprobe for the freezing of targeted tissue. The invention facilitates the eradication of tissue and can thereby decrease hospitalization time; and further limit postoperative morbidities, shorten return to daily functions and work, and further reduce the overall treatment cost. These improvements to device design and application can also increase utilization of the device for the treatment of multiple disease states.
[0046] The current device represents an improved development of cryosurgical devices by allowing for controlled linear flow of a cryogen without the need for high pressure or compression based bellows or piston systems. Further, the device contains a novel baffled linear heat exchanger designed for cryogen flow through a specialized subcooling chamber.
[0047] The embodiments of the present invention may be modified to take the shape of any device, container, apparatus, or vessel currently used in industry. Specifically, cylindrical or alternative vessels may provide containers for the cryogenic system for improved cryogenic supply and delivery. Further, any compartmental arrangement in combination with the components of the above system may take many forms and be of any size, shape, or passageway. Any number of vents may also be utilized to facilitate operation of the system. The system may also be a partially closed or completely closed system.
[0048] In one embodiment of the system, the device is contained within a console, a shell or enclosure that allows the system to be easily transported. The enclosure may then include any mobile feature such as wheels, handles, and fixtures (or allow placement onto a cart having these features) so that the system can be transported to and from the location of treatment. Such mobility allows the system to be easily moved to and from an operating room or site of therapeutic treatment. It is also noted that the system is readily separable from the cryogen fill tanks and fill lines that initially supply the system with the liquid nitrogen or other such cryogenic fluid at the supply port 29 (As shown in FIG. 1 ). This improved feature eliminates the bulkiness of standard cryogenic medical devices.
[0049] As presented, the multiple embodiments of the present invention offer several improvements over standard medical devices currently used in cryogenic industry. The improved cryogenic medical devices remarkably enhance its utilization for the cooling, delivery and return of a liquid cryogen to a cryoprobe for the freezing of targeted tissue. The present invention provides cost savings and significantly reduced treatment times which further reduce expenditures in the healthcare setting. The previously unforeseen benefits have been realized and conveniently offer advantages for the treatment of multiple disease states. In addition, the improvements enable construction of the device as designed to enable easy handling, storage, and accessibility. Further uses of the system outside of the healthcare setting are foreseeable. Potential uses in the space industry, defense systems or any industry requiring rapid cooling may incorporate the cryogenic system as thus described.
[0050] As exemplified, the device may include any unitary structure, vessel, device or flask with the capacity to integrally incorporate any combination of such structures. The invention being thus described, it would be obvious that the same may be varied in many ways by one of ordinary skill in the art having had the benefit of the present disclosure. Such variations are not regarded as a departure from the spirit and scope of the invention, and such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims and their legal equivalents. | A cryogenic medical device for delivery of subcooled liquid cryogen to various configurations of cryoprobes is designed for the treatment of damaged, diseased, cancerous or other unwanted tissues. The device is a closed or semi-closed system in which the liquid cryogen is contained in both the supply and return stages. The device is capable of generating cryogen to a supercritical state and may be utilized in any rapid cooling systems. As designed, the device comprises a number of parts including a vacuum insulated outer dewar, submersible cryogen pump, baffled linear heat exchanger, multiple pressurization cartridges, a return chamber, and a series of valves to control the flow of the liquid cryogen. The cryogenic medical device promotes the subcooling to any external cryogenic instrument. | 5 |
This application claims the priority benefit of provisional application Ser. No. 60/029,346 filed Oct. 31, 1996.
BACKGROUND OF THE INVENTION
During the development of a commercially viable asymmetric synthesis of potent CA 1 A 2 X analogs which inhibit farnesyl-protein transferase and are useful in the treatment of cancer, a highly stereoselective synthesis of a key intermediate, a substituted proline derivative, needed to be developed. A variety of methods of general applicability have been worked out by Chung, J. Y. L., et al. J. Org. Chem 1990, 55, 270-27. We have found that the previously disclosed process requires resolution of enantiomers, costly starting materials and does not provide adequate control over the pyrrolidine ring relative stereochemistry. Accordingly, an alternative processes to obviate the difficulties is desired.
SUMMARY OF THE INVENTION
This invention encompasses a method for the stereoselective synthesis of alkyl prolines of the general Formula I, intermediates of the farnesyl-protein transferase inhibiting CA1A2X motif of the protein Ras, via the intermediacy of novel hydroxy-amides of the general Formula Ia. ##STR1## The instant process employs an efficient diastereoselective 2,3!-Wittig rearrangement of enolates derived from α-allyloxy amides of the general formula 1, wherein R c denotes a nitrogen containing chiral auxiliary and R 1 and R 2 are independently selected from the group consisting of H, C 1-6 alkyl and aryl. The products of the rearrangement (i.e., compounds of Ia) are then subjected to an intramolecular hydroboration/cycloalkylation reaction as disclosed by Evans, D. A. et al. J. Am. Chem. Soc. 1987, 109, 7151-7158 which allows for retention of the pre-existing acyclic stereochemistry of the alkyl proline products. The instant process eliminates the need to resolve enantiomers, provides more precise control over the pyrrolidine ring relative stereochemistry and more cost-effectively utilizes starting materials. This invention also relates to the novel compounds of formula Ia ##STR2## which are products of the 2,3!-Wittig rearrangement.
DETAILED DESCRIPTION OF THE INVENTION
The instant process is generally depicted in Scheme 1 below. ##STR3## wherein X is a salt.
One aspect of the instant invention relates to a method of preparing a compound of formula I ##STR4## or its pharmaceutically acceptable salt, wherein: R 1 and R 2 are independently selected from the group consisting of H, C 1-6 alkyl, and aryl, and R 3 is selected from the group consisting of H, C 1-6 alkyl, aryl and allyl,
which comprises:
rearranging a compound of formula 1: ##STR5## through reaction with a strong base at an initial temperature of about -100° C. to about -50° C., preferably about -85° C. to about -70° C., followed by aging at this temperature for about 30 minutes to about 6 hours; after this initial period, the mixture is heated to a secondary temperature of about -50° C. to about 0° C., preferably about -45° C. to about -20° C. and aged for a at least thirty minutes to provide a compound of formula Ia, ##STR6## wherein: R 2 and R 3 are described above, R c is a chiral auxiliary and* designates a stereogenic center;
esterifcation of Ia with an acidic alcohol for about 30 minutes to about 3 hours to give a compound of formula 3; ##STR7## functionalization of the hydroxy group of 3 using a tertiary amine to provide a compound of formula 4, ##STR8## wherein OR 4 is a leaving group such as Omesylate, Otosylate, Otriflate and the like;
displacing the OR 4 group of formula 4 with sodium azide in the presence of a polar aprotic solvent at a temperature of about 40° C. to about 140° C., preferably, 50° C. to 80° C. to produce a compound of formula 5; ##STR9## and, hydroboration and cycloalkylation of formula 5 with a dialkylborane reagent followed by treatment with an acid to give a compound of formula I or its pharmaceutically acceptable salt ##STR10##
Another aspect of the invention is a method of making a compound of formula II ##STR11## wherein: R 1 and R 2 are independently selected from the group consisting of H, C 1-6 alkyl, and aryl, R 3 is selected from the group consisting of H, C 1-6 alkyl, aryl and allyl, and X is a nitrogen protecting group.
which comprises rearranging a compound of formula 1:
rearranging a compound of formula 1: ##STR12## through reaction with a strong base at an initial temperature of about -100° C. to about -50° C., preferably about -85° C. to about -70° C., followed by aging at this temperature for about 30 minutes to about 6 hours; after this initial period, the mixture is heated to a secondary temperature of about -50° C. to about 0° C., preferably about -45° C. to about -20° C. and aged for a at least thirty minutes to provide a compound of formula Ia, ##STR13## wherein: R 2 and R 3 are described above, R c is a chiral auxiliary and* designates a stereogenic center;
esterifcation of Ia with an acidic alcohol for about 30 minutes to about 3 hours to give a compound of formula 3; ##STR14## functionalization of the hydroxy group of 3 using a tertiary amine to provide a compound of formula 4, ##STR15## wherein OR 4 is a leaving group such as Omesylate, Otosylate, Otriflate and the like;
displacing formula 4 with sodium azide in the presence of a polar aprotic solvent at a temperature of about 40° C. to about 140° C., preferably, 50° C. to 80° C. to produce a compound of formula 5; ##STR16## reducing compound 5 with a reducing agent in the presence of an aqueous acid, followed by treatment with a nitrogen protecting group belonging to the group consisting of Boc, Bn, Alloc, FMOC, acetate, and BOM to give a compound of formula II ##STR17##
Yet another aspect of this invention is a compound of formula Ia ##STR18## wherein: wherein R 1 and R 2 are independently selected from the group consisting of H, C 1-6 alkyl and aryl and R c selected from the group consisting of ##STR19##
The rearrangement step can be carried out in organic solvents such tetrahydrofuran (THF), toluene, xylenes, dimethylforamide, Et 2 O, DME and the like, preferably THF and Et 2 O and requires the use of about 0.5 to about 3.0 equivalents, preferably about 1.0 to about 2.5 equivalents of a strong base such as LDA, NaH, KH, LHMDS, n-BuLi, NaHMDS, KHMDS and the like, preferably LHMDS or LDA. Additives (about 0.5 equivalents to about 30 equivalents, preferably about 1.0 to about 18 equivalents, more preferably about 1.0 to about 7 equivalents) such as CP 2 ZrCl 2 , HMPA, TMEDA, DMPU and the like, preferably HMPA are useful in this rearrangement step and therefore may optionally be added. The concentration of formula 1 can range from about 0.05 to about 0.3M. The preferred initial temperature range for the rearrangement step is -85° C. to about -70° C. which is maintained for about 30 minutes to about 6 hours, at which point the mixture is heated to a preferably temperature of about -15° C. to about -5° C.
The esterification step can be carried out using refluxing acidic aqueous alcohol, wherein the acidic alcohol is about a 3 to 1 ratio of alcohol to acid, wherein the alcohol is selected from a group consisting of methanol, ethanol, propanol, butanol, benzyl and isopropanol and the acid can be selected from a group consisting of anhydrous HCl, HCl, TsOH, MsOH, sulfuric acid and the like. The esterification step can optionally be accomplished in two steps via known acid alkylation with an alkylating agent such as diazomethane and the like.
The functionalization step can be carried out by functionalizing the hydroxy group of formula 3 as its mesylate or tosylate using for example a tertiary amine base such as triethylamine, diisopropylethylamine, dimethylethylamine, and dimethylpentylamine and the like followed by displacement with sodium azide in the presence of a polar aprotic solvent such as DMSO, DMF and the like at a temperature of about 40° C. to about 140° C., preferably, about 50° C. to about 80° C. to produce a compound of formula 5.
The hydroboration/cycloalkylation steps are known and can be carried out, for example, by using a dialkylborane reagent such as dicyclohexylborane, 9-BBN and the like, preferably dicyclohexylborane in the presence of an organic solvent such as THF, toluene, xylenes, dimethylforamide, Et 2 O, DME and the like, preferably THF, followed by treatment with an aqueous acid such as 1N to 12N HCl or 1N to 18N H 2 SO 4 .
The reduction and protection steps are also known and can be carried out, for example, using a reducing agent such as triphenylphosphine (PPh3) and an aqueous acid such as 1N to 12N HCl or 1N to 18N H 2 SO 4 in the presence of an organic solvent such as THF, or alternatively by known catalytic hydrogenation methods, followed by treatment with a nitrogen protecting reagent to incorporate a nitrogen protecting group.
The sequence and conditions of the reaction steps is dependant on the structure and functional groups present. The protecting groups that are necessary and may be chosen with reference to "Protecting Groups in Organic Synthesis, Greene T. W., Wiley-Inerscience, New York, 1981". The blocking groups are readily removable, i.e., they can be removed, if desired, by procedures which will not cause cleavage or other disruption of the remaining portions of the molecule. Such procedures include chemical and enzymatic hydrolysis, treatment with chemical reducing or oxidizing agents under mild conditions, treatment with fluoride ion, treatment with a transition metal catalyst and a nucleophile, and catalytic hydrogenation.
Examples of suitable nitrogen protecting groups are: carbobenzyloxy, t-butylmethoxyphenylsilyl, t-butoxydiphenylsilyl, trimethylsilyl, triethylsilyl, o-nitrobenzyloxycarbonyl, p-nitrobenzyloxycarbonyl, benzyloxycarbonyl, t-butyloxycarbonyl and the like.
A chiral auxilary is defined as an easily removable chiral group of known absolute stereochemistry which is attached at a position near the site of reation and is capable of influencing the stereochemical outcome of the reaction of interest. Some of the chiral auxiliaries useful in this method are: ##STR20##
A preferred chiral auxiliary useful in this invention is wherein R c is (1S,2R)-1-amino-indan-2-ol: ##STR21##
As used herein, "alkyl" is intended to include branched, cyclic and straight-chain saturated aliphatic hydrocarbon groups having the specified number of carbon atoms. Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like.
As used herein, "aryl" is intended to include aryls and heteroaryls, both substituted and unsubstituted, which are defined as carbazolyl, furyl, thienyl, pyrrolyl, isothiazolyl, imidazolyl, isoxazolyl, thiazolyl, oxazolyl, pyrazolyl, pyrazinyl, pyridyl, pyrimidyl, purinyl or quinolinyl as well as aromatic rings e.g., phenyl, substituted phenyl and like groups as well as rings which are fused, e.g., naphthyl and the like. Substitution can be 1 to 3 groups of C 1-6 alkyl, hydroxy, halogen, carbonyl, CO 2 , NO 2 , OC 1-6 alkyl; SC 1-6 alkyl, N(C 1-6 alkyl) 2 and the like.
The pharmaceutically acceptable salts of the compounds of this invention include the conventional non-toxic salts of the compounds of this invention as formed, e.g., from non-toxic inorganic or organic acids. For example, such conventional non-toxic salts include those derived from inorganic acids such as hydrochloric, hydrobromic, sulfuric, sulfamic, phosphoric, nitric and the like: and the salts prepared from organic acids such as acetic, propionic, succinic, glycolic, stearic, lactic, malic, tartaric, citric, ascorbic, pamoic, maleic, hydroxymaleic, phenyl-acetic, glutamic, benzoic, salicylic, sulfanilic, 2-acetoxy-benzoic, fumaric, toluenesulfonic, methanesulfonic, ethane disulfonic, oxalic, isothionic, trifluoroacetic and the like.
It is understood that substituents and substitution patterns on the compounds of the instant invention can be selected by one of ordinary skill in the art to provide compounds that are chemically stable and that can be readily synthesized by techniques known in the art as well as those methods set forth below.
Abbreviations used in the description of the chemistry and in the Examples that follow are:
Ac 2 O Acetic anhydride;
Boc t-Butoxycarbonyl;
n-BuLi n-butyl lithium;
Cp cyclopropyl;
DBU 1,8-diazabicyclo 5.4.0!undec-7-ene;
DMAP 4-Dimethylaminopyridine;
DME 1,2-Dimethoxyethane;
DMF Dimethylformamide;
DMPU 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone
EDC 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide-hydrochloride;
HMPA Hexamethylphosphoramide
HOBT 1-Hydroxybenzotriazole hydrate;
Et 3 N Triethylamine;
EtOAc Ethyl acetate;
FAB Fast atom bombardment;
HOOBT 3-Hydroxy-1,2,2-benzotriazin-4(3H)-one;
HPLC High-performance liquid chromatography;
KHMDS Potassium bis(trimethylsilyl)amide;
LHMDS Lithium bis(trimethylsilyl)amide;
MCPBA m-Chloroperoxybenzoic acid;
MsCl Methanesulfonyl chloride;
NaHMDS Sodium bis(trimethylsilyl)amide;
Py Pyridine;
TFA Trifluoroacetic acid;
THF Tetrahydrofuran;
TMEDA Tetramethylethylene diamine
TMS Trimethylsilane.
EXAMPLES
Examples provided are intended to assist in a further understanding of the invention. Particular materials employed, species and conditions are intended to be further illustrative of the invention and not limitative of the reasonable scope thereof.
Example 1
The amide-acetonide 3 chiral auxiliary wherein R c is (1S, 2R)-1-amino-indan-2-ol can be made on 0.5 mole scale as described in scheme 2 ##STR22##
A THF suspension of NaH (60% in mineral oil) at 0° C., was sequentially treated with THF solutions of trans-2-penten-1-ol and bromoacetic acid over a 1 hour period. Upon completion of the additions the resultant thick reaction mixture was heated to reflux for 8 hours. After aqueous quench, acid/base extration and distillation, an 80% yield of 1a was obtained. Activation of 1a was achieved in iPAc using Vilsmeier conditions (POCl 3 , DMF). The resultant iPAc solution was used directly under Schotten Baumann conditions (2.5 NaOH) to acylate (1S,2R)-1-amino-indan-2-ol. Hydoxy-amide 2 was isolated after concentration of the iPAc layer and trituration of the crude solids with cold pentane (73% yield from 1a). Treatment of 2 with methoxypropene and catalytic MeSO 3 H, in iPAc, gave a 94% yield of amide 3aa b.p.=223°-230° C., 9 torr; α! 23 D=+144° (c2.0, CHCl 3 )!. (1S,2R)-1-amino-indan-2-ol and the process thereof are known and can be found in U.S. Pat. No. 5,413,999 granted to Vacca et al.
Example 2
The generality of the reaction was assessed by the use of a variety of enolate counter ions, reaction solvents and additives for the rearrangement of 3aa below. (Table 1). ##STR23##
TABLE 1______________________________________ AssayEn- Additive %4E %4T Yield oftry.sup.aBase Solvent (equiv.) (2R,3S) (2R,3R) 4E + 4T______________________________________1 LHMDS THF none 79 21 95%.sup.c2 LHMDS Et.sub.2 O none 78 22 93%.sup.c3 KHMDS THF none 66 34 91%.sup.c4 NaHMDS THF none 73 27 80%5 n-BuLi THF none 76 24 94%.sup.c6.sup.bn-BuLi THF Cp.sub.2 ZrCl.sub.2 (1.2) 94 7 73%7 LHMDS THF HMPA(3.0) 86 14 95%.sup.c8 LHMDS THF HMPA(5.0) 87 13 96%.sup.c9 LHMDS THF HMPA(10.0) 88 12 95%.sup.c10 LHMDS THF HMPA(15.0) 89 11 97%.sup.c11 LHMDS THF TMEDA(10.0) 80 20 90%.sup.c12 LHMDS THF DMPU(16.0) 85 15 92%.sup.c______________________________________ .sup.a Except when noted, all reactions were run at a concentration of 0.1M, with 1.5 equivalents of base, at an initial reaction temperature of -78° C. The reaction mixture was subsequently aged for 2 hours at this temperature,. warmed to -10° C. over the course of approximately 2 hours and assayed by GC. .sup.b 1.2 equivalents of base were used. .sup.c For entries 1-3, 5 and 7-12 the remaining materials consisted of one diasteromer of 2,3! rearrangement as determined by .sup.1 H and .sup.13 C NMR. On a preparative scale this minor product was cleanly separated by silica gel chromatography.
2,3! rearrangement of the lithium enolate of amide-acetonide 3aa provided a greater than 98% assay yield of products resulting from 2,3! sigmatropic rearrangement (Table 1, entry 1). See Nakai et al., Organic Reactions, vol. 46, John Wiley & Sons, Inc.; New York, N.Y.; 1994; pp 105-210 for a review of the 2,3!-Wittig rearrangement. The diastereoselectivity for the rearrangement of the enolate of 3aa was observed to be a function of enolate counter ion, with erythro selectivity increasing from K<Na<Li<Zr (Table 1). Although selectivity favoring 4E was highest using Katsuki's zirconium enolate protocol, there was a reduction in the conversion of 3aa. Modification of this protocol (increasing n-BuLi to 2.0 equivalent) lead to consumption of 3aa, however a low assay yield of 4E, and 4T was still observed.
Using LHMDS as a base and employing HMPA as an additive, resulted in higher levels of erythro selectivity than in the absence of HMPA (Table 1, entry 1 vs. entries 7 through 10). Unlike the. zirconium enolate case, the enhanced levels of diastereoselectivity observed in the presence of HMPA did not come at the expense of assay yield. Optimal selectivity on a 1 mmol scale was obtained using 15 equivalents of HMPA (Table 1, entry 10), a level of HMPA deemed unacceptable on large scale.
Reducing the HMPA charge to 5 equivalents on a 0.2 mol scale resulted in an acceptable compromise between diastereoselectivity and level of HMPA (91% assay yield of 2,3! products containing the 2R configuration: 86% 4E: 14% 4T). The reaction was quenched with 0.1N sodium phosphate buffer (pH=6.8) and the aqueous layer extracted with iPAc. The organic layer was washed three times with H 2 O to remove the residual HMPA and concentrated to give a yellow-orange oil. Filtration through a short deactivated silica gel column (8 X weight of crude oil, 1% Et 3 N in 10% EtOAc in hexane) gave 80% yield of a 85:15 4E:4T mixture as an oily solid. Further enrichment in 4E was achieved by trituration with pentane (4° C.) to give an overall 67% yield (94:6 4E:4T) from 3aa as a white powder. Both amide 3aa and hydroxy-amide 4E exist at room temperature, in CDCl 3 , as a 97:3 mixture of rotomers as determined by magnetization transfer upon irridation of the H1' proton of the amino-indanol auxiliary.
The stereochemistry of 4E was determined by a X-ray diffraction study as (2R,3S). An analytically pure sample of 4E white crystalline, m.p.=97.5°-98° C., α!23D=+133° (c1.0, CHCL 3 )! was available by normal phase, preparative HPLC on a YMC-pak CN column. The (2R,3R) stereochemistry of 4T was deduced by removing the C.3 stereocenter via olefin hydrogenation of a 9:1 4E:4T mixture (10% Pd/C, EtOH). The resultant product was determined to be diastereomerically pure by 1 H, and 13 C NMR.
The diastereomeric ratios of 4E:4T were routinely assayed on a HP 6890 GC with FID, using a splitless injection of a heptane solution onto a 5m HP-1/30 DB-23 joined column.
Example 3
The following amide-acetonides 13-17 were also made available following the previously described method, and their respective 2,3!-Wittig rearrangements carried out under identical conditions (Table 2). ##STR24##
TABLE 2______________________________________ Crude Isolated Assay Major Minor YieldEntry R.sup.3 R.sup.2 Yield (Config.) (Config.) (4Ea:4Ta)______________________________________13 H Me 97% 90% 10% 67% (2R,3S) (2R,3R) (94:6)14 H Et 96% 87% 13% 67% (2R,3S) (2R,3R) (94:6)15 Et H 93% 32% 68% not (2R,3S) (2R,3R) attemped16 H H 95% >98% NA 88% (NA) (2R)17 H Ph 87% 91% 9% 68% (2R,3R) (2R,35) (93:7)______________________________________
Generally, the entries possessing the trans-disubstituted geometry (entries 13, 14 and 17) afforded excellent selectivity for 2R,3S configuration (erythro). The rearrangement of the lithium enolate of amide 15, containing a cis-disubstituted olefin geometry, ed in lower 2R,3R selectivity (ca. 2:1 threo:erythro). Amide 16, possessing a terminal olefin, afforded greater than 98% 2R selectivity. The absolute stereochemistry of the 2,3!-Wittig rearranged products of amides 13 and 16 were determined after conversion to L-isoleucine and L-norvaline, respectively, followed by GC comparison of their trifluoracetamide methyl esters to authentic samples on a Alltech Chirasil-Val column (25m) as per: Abe et al., S. J. High Res. Chromo. Comm. 1981, 549.
Example 4
The utility of the 2,3!-Wittig products can be demonstrated, for example, by converting 4E to functionalized amino acids 11 and 12 as depicted in Scheme 5. ##STR25## Reagents and conditions: a. MeOH: 12N HCl (3:1), 1 hour (74%); b. i) MsCl, Et 3 N, CH 2 Cl 2 (92%), ii) NaN 3 , DMSO (76%); c. i) PPh 3 , 1N HCl, THF, ii) Boc 2 O, SN NaOH, THF (80%); d. Cx 2 BH, THF, then 1N HCl, (78%).
Auxiliary solvolysis was routinely carried out on a 94:6 ratio of 4E:4T or better, and was achieved in refluxing aqueous methanol (3:1 v/v MeOH: 12N HCL) to afford a 74% distilled yield of hydroxy-methyl ester 9 with a 90% HPLC assay recovery of amino-indanol. Conversion of 9 to azide 10 occurred in two steps under standard conditions (overall 70% yield). Reduction of 10 under Staudinger conditions and Boc protection of the crude amine gave 11 in 80% yield after purification. Alternatively, treatment of 10 with dicyclohexylborane afforded (2S,3S)-3-ethyl proline HCL 12 in 78% yield after acidic hydrolysis of the intermediate aminoborane with aqueous HCL (Azide 10 (92% de) underwent hydroboration-cycloalkylation to afford 12 as a 88:12 (76% de) mixture of trans:cis proline ring isomers, as determined by 1 H NMR). | The invention encompasses a method for the stereoselective synthesis of alkyl proline and other amino acid derivatives which are intermediates of the farnesyl-protein transferase inhibiting CA 1 A 2 X motif of the protein Ras. The instant process employs an efficient diastereoselective 2,3!-Wittig rearrangement of α-allyloxy amide enolates mediated by a chiral auxiliary to provide acyclic and cyclic precursors. | 2 |
CROSS REFERENCE OF RELATED APPLICATION
[0001] This is a Continuation-In-Part application of a non-provisional application having an application Ser. No. 11/415,714 and a filing date of May 1, 2006.
BACKGROUND OF THE PRESENT INVENTION
[0002] 1. Field of Invention
[0003] This invention generally relates to a multiple layering means of dust protection split boot cover, specifically relates to a protective laminated multiple-layered split boot layer assembly system for a jointed coupling and device to-be-protected on axle ( 20 ). Its use is in applications such as a constant velocity joint, tie-rod, a guiding, controlling, steering, and push-pull piston-cylinder assembly. In other words, this present invention and method can be applied to any “threading through an axle” installation of protective dust covering split boot layer without the troublesome dismantling and consequent re-assembly of related parts and components, resulting in easy installation. The jointed coupling or device to-be-protected on axle ( 20 ) needs to be protected from harmful elements but good, helpful lubricants and grease need to be retained inside the present invention of protective laminated multiple-layered split boot layer assembly, easy installation achieved with a substantially high degree of reliability and integrity.
[0004] 2. Description of Related Arts
[0005] Usually non-split boots (as used in constant velocity joints, rack and pinion steering control bar or column, piston-cylinder assemblies, like hydraulic, air, pneumatic, etc) can be installed quite easily at initial machine assembly, since all parts and components are assembled together anyway. However, when such a non-split boot has a cut, a tear, a crack, a leak, or simply grown worn out, it may lose valuable grease or lubricant inside and allow external elements such as water, dust, dirt, or sand to enter causing faster deterioration and eventual destruction of the joint. In that case, replacement of the traditional non-split boot with yet another traditional non-split boot would require annoying disassembly-and-re-assembly of the joint and related components because of the need to thread the jointed coupling or device to-be-protected on axle ( 20 ) shaft through the boot. This disassembly and re-assembly requirement can mean very involved and labor-intensive tasks requiring many tough, grueling hours of labor, requiring a lot of patience and involving certain substantial risks as well, as will be discussed later.
[0006] Many automobiles today, like some rear-wheel drive and four-wheel drive as well as almost all front-wheel drive automobiles are equipped with constant velocity joints. Drive trains for front-wheel drive automobiles usually are made up of two half-shafts. Half-shafts comprise of an axle connected together by the use of constant velocity joints. Each half-shaft typically contains two constant velocity joints. The constant velocity joint nearest to the centerline of the automobile is commonly called the “inboard” joint, while the constant velocity joint or generally a jointed coupling axle shaft closest to the wheel assembly is commonly referred to as the “outboard” joint. The constant velocity joints allow one axle's rotating motion to be transferred to another axle, which eventually leads to the wheel rotation. Additionally, constant velocity joints allow the axles to accommodate the up and down motion of the joints. These joints have to be kept lubricated, and protected from dust, dirt, and debris by covering with a flexible cover or “boot”.
[0007] Many methods, means, inventions and contraptions have been thought out and many of them do achieve some goals of avoiding the need of dismantling, consequently re-assembly, even re-calibration of related parts and components. However, they miss out or fail to address the other equally important, if not more important goal of achieving a certain acceptable level of substantial dust, dirt, and lubricant tightness. Due to this only partial achievement of the aforementioned main goals, many people has no choice but still has to continue buying the good old-fashioned and traditional non-split integral dust boot assembly replacement over solution products as split boot replacements currently on the market.
[0008] For example, Belter in U.S. Pat. No. 4,813,913 shows a Protective boot assembly which describes a zipper and the use of a flexible sealant material in order to more effectively seal the zipper or similarly employed fastener mechanism.
[0009] Another one-piece split boot U.S. Pat. No. 4,676,513 by Tiegs, et al has screw type formed from a unitary, flexible body shaped to be helically wrapped around a universal joint forming a generally hollow truncated conical configuration with, as mentioned—a corrugated, helical shape.
[0010] U.S. Pat. No. 5,182,956 by Woodall, et al also had a protective boot split along a longitudinal seam closed by a zipper, a hook and loop type fastening strip, or other suitable attachment devices.
[0011] Also, Ron O. Biekx in U.S. Pat. No. 6,139,027 describes a CV (constant velocity) joint boot with sealing sleeves being longitudinally split boot with somewhat elaborate system of multiple parts and components making it tighter around protected part and is quite different from my invention.
[0012] Still other current art devices are U.S. Pat. No. 5,845,911 of Gimino and U.S. Pat. No. 5,222,746 of Van Steenbrugge from Belgium, with U.S. Pat. No. 5,845,911 using a replacement split boot assembly with elaborate arrangement of holes and rivets to hold the assembly together during operation. While U.S. Pat. No. 5,222,746 of Van Steenbrugge uses boot bellow halves made from a flexible material, comprising jointing snap-lockable closure means. Such closure means of lateral U-shaped interlock housing with a seam having an interlocking tongue on one side of the seam and a U-shaped groove on the other, fastened together by adhesive.
[0013] However, as stated before, all these devices and inventions do not really solve the issues associated with a protective split boot. With the protective boot split (to avoid threading in the axle), the split boot can open up to enclose around the jointed coupling or device to-be-protected on axle ( 20 ). It can also open up for all kind of adverse environments and foreign elements like dust, dirt, water, abrasives and sand, etc. Thus the seemingly elusive solution lies in effectively sealing out the bad harmful contaminants from entering the split boot and yet still prevent lubricant from leaving the area where it is supposed to stay to protect and lubricate.
[0014] Additionally, many of these prior arts, may even suffer from a major functional flaw in that, at times split boot can split open up prematurely, unpredictably, or even worse still intermittently, adding an element of surprise. Leaving us with a false sense of security of its proper functioning while it occasionally splits open during operation. This allows in and accumulate a lot of harmful dirt, sand grains, debris inside the split boot, and the part-to-be-protected ( 20 ) is constantly worn out by those harmful debris, abrasives, sand and dirt, etc. Imagine when it happens during crucial demanding high-speed freeway operation. Once again, all these risk possibilities are what make current solution products poor substitutes for the good old, regular traditional, non-split boot.
[0015] A jointed coupling or device to-be-protected on axle ( 20 ) or drive as in a constant velocity joint or a tie rod joint needs a boot assembly that can withstand continuous twisting, turning movement. Similarly, a protective piston-cylinder boot or a rack and pinion push-pull rod assembly must have sufficient strength to withstand numerous compressions and extensions of the actuating column rod. That is the reason why simple as it may look, in actuality getting these boot assemblies to perform on the same performance level as the good old, traditional, integral, non-split boot is no easy task. The need to improve is there and many solution products make it to the market, yet none is really quite successful.
[0016] All prior inventions and patents mentioned, taken either singularly or in combination, concerning protective split boots, are not seen to describe the present invention as claimed, do not completely solve the aforementioned problems and can be called quite unacceptable. Thus an effective and viable solution solving the aforementioned problems is definitely needed and desired.
SUMMARY OF THE PRESENT INVENTION
[0017] The present invention provides a quick and easy installation of protective split boot layer without the usual tough and often messy job of dismantling and re-assembling back together a substantial portion of related parts and components. These are accomplished without compromising on the overall split boot performance and integrity, offering substantially the same quality level as the old-style, regular, integral, or whatever one wants to call the traditional non-split boot.
[0018] For example, in the case of the jointed coupling or device to-be-protected on axle ( 20 ) in a typical automobile protective boot replacement of CV (constant velocity) joint, the rack-and-pinion unit, and tie-rod joint unit, substantial dismantling of wheel, control arms, etc. is a must. Later, followed up by the equally tough if not tougher job of re-assembly them back together, plus possible re-calibrations and readjustments. All these dismantling and re-assembly are done with the hope of not upsetting the then recent correct working settings, or status quo before the boot replacement. With the laminated multiple layered split boot assembly system, not only that the troublesome mandatory disassembly and re-assembly procedures are eliminated, thus allowing for quick and easy installation. Its one major advantage of substantially higher level of protective split boot integrity and sealing protection of vital part is also finally attainable and achieved.
[0019] The problems that come with the so very unnecessary and senseless disassembly followed by re-assembly of related parts and components as stated above, can be quite many. Such as misplacement or even loss of parts, incorrect disassembly and wrongful re-assembly, bad re-calibrations or re-adjustments (if calibrations or adjustments are ever needed, as in some cases).
[0020] Think of all the hassles and possible disastrous damage, frustrations and spent time and effort. Worse still, if some kind of strong brute force is somehow applied, say in disassembly-assembly, leading to damage or even severe permanent damage requiring further repair or replacement of other additional parts and components and re-calibration or re-alignment (such as wheel alignment) which as everyone knows, can be very expensive. These are the visible, discernible and known damage we can see and hear, what about invisible, hidden, serious, careless damage such as not properly tightened bolts and nuts, hidden damaged screw thread that can lead to serious accidents with possible loss of limbs and life. As the saying goes, “If it ain't broken, do not do anything about it!” In our case, unnecessary dismantling is unwise and should be cut down or avoided at all cost if possible and this is where the present invention can help avoid all these other unacceptable side effects and should I say, serious collateral damages.
[0021] To provide a truly acceptable level of reliability with protective split boot dust sealing integrity, in term of preventing harmful elements from getting inside the moving parts as well as retaining the good stuff like grease and lubricants from leaving, so it can do its good job of lubricating.
[0022] As it is common knowledge, what lack of grease or lubricant can mean, it is the dreaded, damaging metal to metal contact. So this present invention is meant not just to achieve rapid boot installation especially rapid boot replacement, avoidance of redundant disassembly and re-assembly procedure. It also attempts to raise the current state of the art or of integrity and reliability in protective split boot assembly to an even higher level, especially in terms of sealability and durability, approximately on the same level as the good old, traditional non-split boot. Basically the prior arts do not use multiple layering means of multiple split boot layer sealing like this present invention does. It is out to achieve what others failed so far.
Advantages
[0000]
1) The present invention can make the installation much easier than the regular, good old, traditional non-split boot installation. It accomplishes this by splitting a boot layer in at least three ways of cutting, categorized by type ‘A’, ‘B’ and ‘C’ cuts, as will be further described later. It should be quite obvious that the possible number of cutting ways will not be limited to just three. When needed, more than 3 ways is still always possible, for example—random and arbitrary cuts can provide many additional ways. In other words, the three ways (namely, ‘A’, ‘B’ and ‘C’) of cutting are shown only as three of many possible examples here and discussed later in split boot layer cut type reference table. It is a revolutionary solution to some problems associated with many kinds of split boots, and is different from other products currently on the market, providing better advantages as can be seen further below.
2) The present invention utilizes not just one but at least two split boot layers, in other words, multiple split boot layers assembly providing better, advantageous sealing capability so far unavailable with virtually all products currently on the market.
3) It uses glue, sealant adhesive to laminate and reinforce the split boot layers assembly integrity. The material used in the present invention of split boot layer then has to be compatible and receptive of sealant glue or else has to be coated with primer glue coating.
4) Some other products may also use sealant glue adhesive, however one marked difference in this respect, is with other split boots, glue is applied only to very limited small glue coverage surface area and thus making only weak bonding. The present invention is different, the sealant glue adhesive application coverage area involved is substantially the entire or at least very large mating surface area of each abutting split boot layer (or even involving both abutting split boot layers). Because entire mating abutting surface area are coated with glue sealant adhesive, it provides extremely strong bonding power between two whole abutting mating glued and laminated surface areas of split boot layers, not seen or available in other products. Depending on what other prior arts are compared, the present invention uses substantially several, maybe tens, or even hundreds if not thousands times more gluing surface area than some other products used in a similar condition, providing unquestionably superior bonding strength. Huge or larger gluing surface area translates into super strong and substantial increase in sealing bond. Please also note: dual glue sealant adhesive coatings ( 140 ) can make glue bond even stronger, maybe doubly stronger.
5) Additionally, with using the entire or halves of split boot layers, comes the advantage of using the whole or half of split boot layers like some kind of glue reservoir holding glue sealant, consequently much reduced chance of dripping, dropping glue leading to unnecessary, unsightly, contaminating, gluey mess. This also is unavailable with other products either. Additionally, this reservoir effect helps with glue application over the entire inside surface area ( 80 ) of the split boot layer.
6) With this multiple layered split boot layers assembly, clamping, claming, clasping, embracing, enclosing, wrapping around effect and clumping together effect of a formed shape is put to good use. It provides strong powerful and effective clamping of each upper-layer split boot layer upon the previous lower-layer ( 145 ) bring out a lot of added strength to firm up the final integrated, glued, laminated and sealed split boot layer's integrity.
7) There is also another unique important advantage with laminated multiple layered split boot layers assembly, the number of split boot layers can be increased as much as needed, limited only by the available physical space around the split boot layers assembly installation area. This is made all the more possible when all subsequent, successive, additional upper-layer split boot layers (except the very first split boot layer, which needs to be thicker) can be made substantially thin and skinny, so numerous multiple split boot layers can be layered upon each other. With the exception of aforementioned physical space limitation and the other possible limit of whether there is really the need for that many split boot layers, there actually is no set limit as to how many split boot layers can be assembled this way. Needless to say, more layers mean thicker, stronger and thus more overall split boot's sealing performance and durability.
8) The present invention thus makes possible not just the easy boot installation or replacement but also for split boot integrity and reliability (which is virtually non-existent before), thus finally offering a true substitute and alternative. Any protective boot device that needs to thread a jointed coupling or device to-be-protected on axle ( 20 ) through that boot can benefit from it. With this kind of boot integrity level achieved with my multiple layered laminated split boot system, it will be a real challenge and competition to the current dominant traditional non-split boot market share (especially in the area of replacement boot maintenance). It will immensely benefit the customers waiting for this kind of easy installation split boot performance and capability to finally show up on the market.
[0031] In other words, replacement of boot assembly will then be a snap without compromising on the required substantially high level of performance, rivaling the regular, traditional non-split boot assembly.
9) The present invention is not just limited to flexible, soft or softer shell split boot layer (as in the examples of CV joint boot, rack-and-pinion column boot, and tie-rod). It is applicable to the substantially hard, or more rigid shell split boot layer, which can surely enjoy using my laminated and integrated multiple-layered protective split boot layer assembly system. 10) The present potential crowd-pleaser invention is set to please and benefit not only regular, off-the-street customers but also the professional mechanics. (a) It is set to empower the DIY's (do-it-yourselfers), weekend home mechanics warriors, rewarding them with good, easy, highly reliable, performance new or replacement split boot system that had failed and eluded them all these times. (b) Another sure thing is with the easy installation comes with split boot sealability performance in the present invention of a multiple-layered laminated split boot layer assembly system ( 90 ), the joy and better installation job quality due to personal involvement will sure make a car owner installer very proud and save some money as well. 11) More variations are also possible with more split boot layers as seen fit in creating further different combinations and thus embodiments of laminated multiple-layered split boot layers, affording and empowering the user of multiple-layered laminated split boot layer assembly system ( 90 ), the flexibility of many different combinations and configurations for different application requirements. 12) A big bonus benefit is here. Now that with easy installation plus reliability finally available and within easy reach, there will be more prompt and more frequent split boot layers assembly replacements, which in turn, will lead with positive results to: (a) Safer roads and streets just mainly due to improved, easier, reliable and more frequent maintenance; (b) the present invention of laminated multiple layered split boot is set to truly help protect the main process of motion that drives most of the automobiles today, namely the constant velocity boots by way of: (c) less unnecessary mechanical breakdown; (i) leading to longer life for expensive, resource-extensive equipments like automobiles, countless heavy equipments like bulldozers, earth movers, crane, trolleys, forklifts, etc.; (ii) helping to conserve world and global resources, think about unnecessary, premature wear and tear leading to replacements of more expensive related, peripheral parts and components such as CV joint, axle, or entire rack and pinion column unit, tie-rod joint, or even the entire hardware equipments, etc., plus the accompanying labor cost; (d) eliminating the senseless disassembly and re-assembly process means: (i) Less unnecessary misplaced or lost parts and components (during disassembly and re-assembly process); (ii) Less status quo upsetting dismantling and its accompanying so very redundant re-calibration, re-adjustment or worse still damage due to undue brute force possibly used in the process ending with maybe expensive replacement;
Overall:
[0000]
(e) less regretful mishaps, events, frustrations, and better working, living environments for everyone;
(f) Less unsightly, dirty-looking, or torn dust boots spreading grease contaminants wherever they go;
(g) Helps provide and promote safer, quality working and living environments for all, when hardware are maintained properly through the use of my multiple layered split boot system;
(h) Last but definitely not of the least importance, again it helps create much safer transportation for all.
[0050] Further objects and advantages will become apparent from a consideration of the ensuing descriptions and drawings.
[0051] In accordance with the invention, integrated, sealant glue adhesive reinforced, laminated, multiple-layered, protective split boot layer system in the present invention set out to achieve two major goals. First off a quick easy installation without all the so very unnecessary, senseless, and redundant dismantling and its ensuing re-assembly jobs. Secondly, to provide good, reliable, satisfactory, protective shield means for the device to-be-protected on axle ( 20 ) and yet retain good elements like grease or lubricant. The result is a laminated, integrated, multiple layered, protective means using a laminated multiple-layered split boot layer assembly system ( 90 ), installed with properly positioned slit or split line where necessary for split boot layer system's sealing performance using sealant glue adhesive reinforcement.
[0052] These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] FIG. 1A shows first embodiment (as in a constant velocity joint boot) split boot layer assembly, in an exploded view. The first split boot layer is of pivoted or type ‘B’ cut. The subsequent second and third split boot layers are both of halved or type ‘C’ cut.
[0054] FIG. 1B shows first embodiment (as in a rack and pinion unit's boot) split boot layer assembly, in exploded view. The first split boot layer is of pivoted or type ‘B’ cut, while subsequent second and third split boot layers are both of halved or type ‘C’ cut.
[0055] FIG. 1C shows first embodiment (as in a tie-rod boot) split boot layer assembly, in exploded view. The first split boot layer is of pivoted or type ‘B’ cut, while successive second and third split boot layers are both of halved or type ‘C’ cut.
[0056] FIG. 2A shows second embodiment (as in a constant velocity joint boot) split boot layer assembly, in exploded view. The first, second and third split boot layers are all of halved or type ‘C’ cut.
[0057] FIG. 2B shows second embodiment (as in a rack and pinion unit's boot) split boot layer assembly, in exploded view. The first, second and third split boot layers are all of halved or type ‘C’ cut.
[0058] FIG. 2C shows second embodiment (as in a tie-rod boot) split boot layer assembly, in exploded view. The first, second and third split boot layers are all of halved or type ‘C’ cut.
[0059] FIGS. ( 3 A through 17 C) show third through seventeenth embodiment split boot layer assembly (as used in a constant velocity joint boot, in a rack-and-pinion unit's boot, and in a tie-rod boot, respectively). Unlike FIG. ( 1 A through 2 C), it is not shown as centrally exploded view, instead is serially sequenced view of first, second and third split boot layers starting from left to right on each row. On each row, starting from leftmost split boot layer and following the block arrow going to the right, and progressively taking on each upper-layer split boot layer. First split boot layer enclosed the device to-be-protected on axle ( 20 ), next subsequent successive split boot layer then snapped, layered onto the previous, or lower-layer split boot layer ( 145 ). The first, second and third split boot layers ( 5 C, 5 R, 5 T), ( 10 C, 10 R, 10 T), ( 15 C, 15 R, 15 T) can be of all different combinations or mix of type ‘A’, ‘B’ and ‘C’ cuts. The orientation of the cut ( 53 ) or slit of each upper-layer split boot layer in relationship to its preceding lower-layer split boot layer ( 145 ) underneath is instrumental to the split boot layer sealing effectiveness, further discussions will follow.
[0060] FIG. ( 3 A, 3 B, 3 C) show third embodiment using first, second and third split boot layers ( 5 C, 5 R, 5 T), ( 10 C, 10 R, 10 T), and ( 15 C, 15 R, 15 T), all of regular or type ‘A’ cut ( 40 C, 40 R, 40 T) for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0061] FIG. ( 4 A, 4 B, 4 C) show fourth embodiment using first, second and third split boot layers lo ( 5 C, 5 R, 5 T), ( 10 C, 10 R, 10 T), and ( 15 C, 15 R, 15 T), all of pivoted or type ‘B’ cut ( 45 C, 45 R, 45 T) for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0062] FIG. ( 5 A, 5 B, 5 C) show fifth embodiment using first split boot layer ( 5 C, 5 R, 5 T) with pivoted or type ‘B’ cut, second split boot layer ( 10 C, 10 R, 10 T) and third split boot layer ( 15 C, 15 R, 15 T). Both second and third split boot layers with regular or type ‘A’ cut for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0063] FIG. ( 6 A, 6 B, 6 C) show sixth embodiment using first split boot layer ( 5 C, 5 R, 5 T) with regular or type ‘A’ cut, second split boot layer ( 10 C, 10 R, 10 T) and third split boot layer ( 15 C, 15 R, 15 T). Both second and third split boot layers with pivoted or type ‘B’ cut for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0064] FIG. ( 7 A, 7 B, 7 C) show seventh embodiment using first split boot layer ( 5 C, 5 R, 5 T) of halved or type ‘C’ cut, second split boot layer ( 10 C, 10 R, 10 T) and third split boot layer ( 15 C, 15 R, 15 T). Both second and third split boot layers with pivoted or type ‘B’ cut for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0065] FIG. ( 8 A, 8 B, 8 C) show eighth embodiment using first split boot layer ( 5 C, 5 R, 5 T) with pivoted or type ‘B’ cut, second split boot layer ( 10 C, 10 R, 10 T) and third split boot layer ( 15 C, 15 R, 15 T). Both second and third split boot layers with halved or type ‘C’ cut for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0066] FIG. ( 9 A, 9 B, 9 C) show ninth embodiment using first split boot layer ( 5 C, 5 R, 5 T) and second split boot layer ( 10 C, 10 R, 10 T) both with pivoted or type ‘B’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with regular or type ‘A’ cut. They are for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0067] FIG. ( 10 A, 10 B, 10 C) show tenth embodiment using first split boot layer ( 5 C, 5 R, 5 T) and second split boot layer ( 10 C, 10 R, 10 T) both with regular or type ‘A’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with pivoted or type ‘B’ cut. They are for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0068] FIG. ( 11 A, 11 B, 11 C) show eleventh embodiment using first split boot layer ( 5 C, 5 R, 5 T) and second split boot layer ( 10 C, 10 R, 10 T) both with halved or type ‘C’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with pivoted or type ‘B’ cut. They are for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0069] FIG. ( 12 A, 12 B, 12 C) show twelfth embodiment using first split boot layer ( 5 C, 5 R, 5 T) and second split boot layer ( 10 C, 10 R, 10 T) both with pivoted or type ‘B’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with halved or type ‘C’ cut. They are for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0070] FIG. ( 13 A, 13 B, 13 C) show thirteenth embodiment using first split boot layer ( 5 C, 5 R, 5 T) with regular or type ‘A’ cut, second split boot layer ( 10 C, 10 R, 10 T) with pivoted or type ‘B’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with regular or type ‘A’ cut. They are for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0071] FIG. ( 14 A, 14 B, 14 C) show fourteenth embodiment using first split boot layer ( 5 C, 5 R, 5 T) with pivoted or type ‘B’ cut, second split boot layer ( 10 C, 10 R, 10 T) with regular or type ‘A’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with pivoted or type ‘B’ cut. They are for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0072] FIG. ( 15 A, 15 B, 15 C) show fifteenth embodiment using first split boot layer ( 5 C, 5 R, 5 T) with pivoted or type ‘B’ cut, second split boot layer ( 10 C, 10 R, 10 T) with halved or type ‘C’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with pivoted or type ‘B’ cut. They are for constant velocity joint, rack and pinion steering column and tie-rod joint, respectively.
[0073] FIG. ( 16 A, 16 B, 16 C) show sixteenth embodiment using first split boot layer ( 5 C, 5 R, 5 T) with halved or type ‘C’ cut, second split boot layer ( 10 C, 10 R, 10 T) with pivoted or type ‘B’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with regular or type ‘A’ cut. They are for constant velocity joint, rack and pinion steering column, and tie-rod joint, respectively.
[0074] FIG. ( 17 A, 17 B, 17 C) show seventeenth embodiment using first split boot layer ( 5 C, 5 R, 5 T) with regular or type ‘A’ cut, second split boot layer ( 10 C, 10 R, 10 T) with pivoted or type ‘B’ cut, and third split boot layer ( 15 C, 15 R, 15 T) with halved or type ‘C’ cut. They are for constant velocity joint, rack and pinion steering column, and tie-rod joint, respectively.
[0075] FIGS. 18A , 18 B, and 18 C all recap and exemplify the previously mentioned embodiments in their respective diagrams in summarized compact combination diagrams matrix formats as used in a constant velocity joint boot, in a rack-and-pinion unit's boot, and in a tie-rod boot, respectively.
[0076] FIG. 18A shows all possible split boot layer assembly embodiments (for a constant velocity joint boot), that can be derived, using split boot layer cut types selected from the specified three cut types.
[0077] FIG. 18B shows all possible split boot layer assembly embodiments (for a rack-and-pinion boot), that can be derived from the given three cut types.
[0078] FIG. 18C shows all possible split boot layer assembly embodiments (for a tie-rod joint boot), that can be derived from the given three cut types.
[0079] The way to read or assemble together a multiple layered laminated split boot layer system from diagrams in FIGS. 18A , 18 B, and 18 C (the summarized compact combination diagrams matrix formats) is to start from the leftmost split boot layer. From there, laterally, horizontally, or diagonally follow each block arrow to select each split boot layer from left to right. In order to arrive at only 3-split boot layer system of my reinforced, laminated, multiple-layered, protective split boot system, select only a total of 2 block arrows (either horizontal or diagonal). This way it will end only with 3 split boot layers, glue laminated together with glue sealant adhesive sandwiched in-between those split boot layers.
[0080] FIG. 19A shows the eighteenth embodiment split boot layer with spiral wrap around flap structure creating a multiple layered, sealant glue adhesive reinforced, laminated, integrated split boot layer assembly as used in a constant velocity joint boot.
[0081] FIG. 19B shows eighteenth embodiment split boot layer with spiral wrap around flap structure creating a multiple layered, sealant glue adhesive reinforced, laminated, integrated split boot layer assembly used in a rack and pinion boot.
[0082] FIG. 19C shows eighteenth embodiment split boot layer with spiral wrap around flap structure creating a multiple layered, sealant glue adhesive reinforced, laminated, integrated split boot layer assembly used in a tie-rod joint boot.
[0083] FIG. 20A shows a multiple-layered laminated split boot layer assembly system ( 90 ) as used in a constant velocity joint with lightly or loosely installed encircling reinforcing ring ( 120 ).
[0084] FIG. 20B shows a multiple-layered laminated split boot layer assembly system ( 90 ) as used in a rack and pinion steering split boot layer assembly with lightly or loosely installed encircling reinforcing ring ( 120 ).
[0085] FIG. 20C shows an eighteenth embodiment of a multiple-layered split boot layer assembly system ( 90 ) with overlapping spiral wrap around flap structure ( 95 ) as used in a constant velocity joint boot with lightly or loosely installed encircling reinforcing ring ( 120 ).
[0086] FIG. 20D shows an eighteenth embodiment of a multiple-layered split boot layer assembly system ( 90 ) with overlapping spiral wrap around flap structure ( 95 ) as used in a rack and pinion steering boot layer assembly with lightly or loosely installed encircling reinforcing ring ( 120 ).
[0087] FIG. 21A shows a section of a multiple-layered split boot layer assembly system ( 90 ) with single sealant adhesive coating ( 135 ).
[0088] FIG. 21B shows a section of a multiple-layered laminated split boot layer assembly system ( 90 ) with dual glue sealant adhesive coatings ( 140 ).
[0089] Various modifications and variations to the embodiments herein chosen for the purpose of illustration will readily occur to those skilled in the art.
[0090] FIG. 22A is a close-up or magnified view of the sealing sleeve ( 35 ) showing 3 split boot layers of substantially equal thickness of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 22B .
[0091] FIG. 22B shows a multiple-layered laminated split boot layer assembly system as in a constant velocity joint boot, assembled with glue sealant adhesive.
[0092] FIG. 23A is a close-up or magnified view of the sealing sleeve ( 35 ) showing 3 split boot layers of substantially equal thickness of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 23B .
[0093] FIG. 23B shows a multiple-layered laminated split boot layer assembly system as in a rack and pinion unit boot, assembled with glue sealant adhesive.
[0094] FIG. 24A is a close-up or magnified view of the sealing sleeve ( 35 ) showing 3 split boot layers of substantially equal thickness of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 24B .
[0095] FIG. 24B shows a multiple-layered laminated split boot layer assembly system as in a tie rod joint boot, assembled with glue sealant adhesive.
[0096] FIG. 25A is a close-up or magnified view of the sealing sleeve ( 35 ) showing thicker first or lowest layer topped off with 2 split boot layers of substantially equal thickness of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 25B .
[0097] FIG. 25B shows a multiple-layered laminated split boot layer assembly system as in a constant velocity joint boot, assembled with glue sealant adhesive.
[0098] FIG. 26A is a close-up or magnified view of the sealing sleeve ( 35 ) showing thicker first or lowest layer topped off with 2 split boot layers of substantially equal thickness of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 26B .
[0099] FIG. 26B shows a multiple-layered laminated split boot layer assembly system as in a rack and pinion unit boot, assembled with glue sealant adhesive.
[0100] FIG. 27A is a close-up or magnified view of the sealing sleeve ( 35 ) showing thicker first or lowest layer topped off with 2 split boot layers of substantially equal thickness of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 27B .
[0101] FIG. 27B shows a multiple-layered laminated split boot layer assembly system as in a tie rod joint boot, assembled with glue sealant adhesive.
[0102] FIG. 28A is a close-up or magnified view of the sealing sleeve ( 35 ) showing 3 split boot layers of substantially equal thickness formed with overlapping spiral wrap around flap structure ( 95 ) of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 28B .
[0103] FIG. 28B shows a multiple-layered laminated split boot layer assembly system with overlapping spiral wrap around flap structure ( 95 ) as in a constant velocity joint boot, assembled with glue sealant adhesive.
[0104] FIG. 29A is a close-up or magnified view of the sealing sleeve ( 35 ) showing 3 split boot layers of substantially equal thickness formed with overlapping spiral wrap around flap structure ( 95 ) of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 29B .
[0105] FIG. 29B shows a multiple-layered laminated split boot layer assembly system with overlapping spiral wrap around flap structure ( 95 ) as in a rack and pinion unit boot, assembled with glue sealant adhesive.
[0106] FIG. 30A is a close-up or magnified view of the sealing sleeve ( 35 ) showing 3 split boot layers of substantially equal thickness formed with overlapping spiral wrap around flap structure ( 95 ) of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 30B .
[0107] FIG. 30B shows a multiple-layered laminated split boot layer assembly system with overlapping spiral wrap around flap structure ( 95 ) as in a tie rod joint boot, assembled with glue sealant adhesive.
[0108] FIG. 31A is a close-up or magnified view of the sealing sleeve ( 35 ) showing thicker first lowest layer, topped off with 2 split boot layers of substantially equal thickness. All three split boot layers formed with overlapping spiral wrap around flap structure ( 95 ) of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 31B .
[0109] FIG. 31B shows a multiple-layered laminated split boot layer assembly system with overlapping spiral wrap around flap structure ( 95 ) as in a constant velocity joint boot, assembled with glue sealant adhesive.
[0110] FIG. 32A is a close-up or magnified view of the sealing sleeve ( 35 ) showing thicker first lowest layer, topped off with 2 split boot layers of substantially equal thickness. All three split boot layers formed with overlapping spiral wrap around flap structure ( 95 ) of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 32B .
[0111] FIG. 32B shows a multiple-layered laminated split boot layer assembly system with overlapping spiral wrap around flap structure ( 95 ) as in a rack and pinion unit boot, assembled with glue sealant adhesive.
[0112] FIG. 33A is a close-up or magnified view of the sealing sleeve ( 35 ) showing thicker first lowest layer, topped off with 2 split boot layers of substantially equal thickness. All three split boot layers formed with overlapping spiral wrap around flap structure ( 95 ) of a multiple-layered laminated split boot layer assembly system ( 90 ) shown in FIG. 33B .
[0113] FIG. 33B shows a multiple-layered laminated split boot layer assembly system with overlapping spiral wrap around flap structure ( 95 ) as in a tie rod joint boot, assembled with glue sealant adhesive.
DRAWINGS—REFERENCE NUMERALS
[0114] 5 C first split boot layer (for constant velocity joint boot)
[0115] 5 R first split boot layer (for rack and pinion unit boot)
[0116] 5 T first split boot layer (for tie rod joint boot)
[0117] 10 C second split boot layer (for constant velocity joint boot)
[0118] 10 R second split boot layer (for rack and pinion unit boot)
[0119] 10 T Second split boot layer (for tie rod joint boot)
[0120] 15 C third split boot layer (for constant velocity joint boot)
[0121] 15 R third split boot layer (for rack and pinion unit boot)
[0122] 15 T third split boot layer (for tie rod joint boot)
[0123] 18 split boot layers
[0124] 20 device to-be-protected on axle
[0125] 25 crest
[0126] 30 trough
[0127] 35 sealing sleeve
[0128] 40 C regular or type ‘A’ cut (for constant velocity joint boot)
[0129] 40 R regular or type ‘A’ cut (for rack and pinion unit boot)
[0130] 40 T regular or type ‘A’ cut (for tie rod joint boot)
[0131] 45 C pivoted or type ‘B’ cut (for constant velocity joint boot)
[0132] 45 R pivoted or type ‘B’ cut (for rack and pinion unit boot)
[0133] 45 T pivoted or type ‘B’ cut (for tie rod joint boot)
[0134] 50 C halved or type ‘C’ cut (for constant velocity joint boot)
[0135] 50 R halved or type ‘C’ cut (for rack and pinion unit boot)
[0136] 50 T halved or type ‘C’ cut (for tie rod joint boot)
[0137] 53 cut
[0138] 55 complete cut
[0139] 60 alignment guiding mark
[0140] 65 pivot line of crests
[0141] 70 incomplete cut
[0142] 75 two split boot layer halves
[0143] 80 inside surface area
[0144] 85 outside surface area
[0145] 90 laminated multiple-layered split boot layer assembly system
[0146] 95 overlapping spiral wrap around flap structure
[0147] 100 beginning flap
[0148] 105 ending flap
[0149] 108 regular thickness layer {as other layer(s)}
[0150] 110 thicker layer (than upper-layer)
[0151] 115 split boot layer's opening
[0152] 120 encircling reinforcing ring
[0153] 130 glue sealant adhesive coating
[0154] 135 single glue sealant adhesive coating
[0155] 140 dual glue sealant adhesive coatings
[0156] 145 lower-layer split boot layer
[0157] 150 upper-layer split boot layer
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0158] According to the preferred embodiment, the present invention provides a laminated multiple-layered split boot for a device to-be-protected on axle 20 or the like. The laminated multiple-layered split boot comprises a plurality of individual boot layers 18 , wherein each of the boot layers 18 is manufactured to form a separated piece.
[0159] Each of the boot layers 18 has a longitudinal slit and defining an opening thereat, wherein each of the boot layers is arranged for discretely enclosing the device to-be-protected on axle 20 through the opening, in such a manner that a boot layer configuration for enclosing the device to-be-protected on axle 20 is selectively accomplished by a predetermined number of the boot layers 18 for simplifying an installation of the split boot and for optimizing a protection of the device to-be-protected on axle 20 .
[0160] According to the preferred embodiment, one of the boot layers 18 forms a first boot layer ( 5 C, 5 R, 5 T) for enclosing the device to-be-protected on axle 20 through the opening, wherein after the first boot layer ( 5 C, 5 R, 5 T) is retained, another boot layer 18 as a second boot layer ( 10 C, 10 R, 10 T) successively wraps around the first boot layer ( 5 C, 5 R, 5 T) at a position that the longitudinal slit of the first boot layer ( 5 C, 5 R, 5 T) is off-set from the longitudinal slit of the second boot layer ( 10 C, 10 R, 10 T).
[0161] The longitudinal slit of the first boot layer ( 5 C, 5 R, 5 T) at an outside surface area 85 thereof is sealed with an inside surface area 80 of the second boot layer ( 10 C, 10 R, 10 T) to seal the opening of the first boot layer ( 5 C, 5 R, 5 T) for enclosing the device to-be-protected on axle within the first boot layer ( 5 C, 5 R, 5 T) and second boot layer ( 10 C, 10 R, 10 T). In particularly, the inside surface area 80 of the second boot layer ( 10 C, 10 R, 10 T) holdingly contacts with the outside surface area 85 of the first boot layer ( 5 C, 5 R, 5 T) to seal the opening of the first boot layer ( 5 C, 5 R, 5 T). In other words, when the second boot layer ( 10 C, 10 R, 10 T) wraps around the first boot layer ( 5 C, 5 R, 5 T), the inside surface area 80 of the second boot layer ( 10 C, 10 R, 10 T) contacts with the longitudinal slit of the first boot layer ( 5 C, 5 R, 5 T) and holds the opening of the first boot layer ( 5 C, 5 R, 5 T) at the closed position. Preferably, the inside surface area 80 of the second boot layer ( 10 C, 10 R, 10 T) adhering with the outside surface area 85 of the first boot layer ( 5 C, 5 R, 5 T) to seal the opening of the first boot layer ( 5 C, 5 R, 5 T), while the first boot layer ( 5 C, 5 R, 5 T) is entirely enclosed within the second boot layer ( 10 C, 10 R, 10 T).
[0162] The very first split boot layer ( 5 C, 5 R, 5 T) is of substantially same thickness or sturdiness as all the subsequent, successive split boot layers ( 10 C, 10 R, 10 T), and ( 15 C, 15 R, 15 T). That very first split boot layer ( 5 C, 5 R, 5 T) can also be substantially thicker or sturdier than the subsequent, successive split boot layers ( 10 C, 10 R, 10 T), and ( 15 C, 15 R, 15 T). This sturdiness allows it to act as a firmer base foundation for the subsequent additional upper-layer split boot layers ( 10 C, 10 R, 10 T), and ( 15 C, 15 R, 15 T) that follow, to build upon with glue sealant bonding sandwiched in-between corresponding adjacent abutting split boot layers. The base foundation can also be a temporary, thicker foam CV boot. The protective seal and strength is the result with durability, whereby forming a “multiple-layered” protective split boot layer assembly system.
[0163] Technically, each split boot layer can be formed by cutting angularly, helically, longitudinally or even randomly or simply arbitrarily cut in anyway as the need arises.
Split Boot Layer Cut Type Reference Table.
[0164] Split boot layer can be categorized into the following three basic types depending on the way it is split or cut:
1.Regular or type ‘A’ cut ( 40 C, 40 R, 40 T): this type cuts a boot layer axially to have one complete axial cut from one sealing sleeve ( 35 ) end to another sleeve ( 35 ) end, whereby forming a horizontal axial slit or one complete cut ( 55 ) split line. It is worth mentioning that the boot layer 18 has a C-shaped cross section to define the opening for receiving the device to-be-protected on axle 20 . 2. Pivoted or type ‘B’ cut ( 45 C, 45 R, 45 T): this cut type is same as the regular or type ‘A’ cut ( 40 C, 40 R, 40 T) but additionally there is a second partial or incomplete axial cut at substantially diametrically opposite position right across the first complete cut ( 55 ). By incomplete cut, it means almost cut through the split boot layer but leaving the tiptop level of the crests ( 25 ), creating a pivot line of crests ( 65 ), thus earning its name pivoted or type ‘B’ cut. The two cuts, one complete cut ( 55 ) split line and another incomplete cut ( 70 ) split line will then be substantially right across each other.
[0167] Therefore, the boot layer 18 forms two boot layer halves pivotally linked along the second incomplete axial cut 70 so as to allow the boot layer 18 being pivotally opened along the first complete axial cut 55 .
3. Halved or type ‘C’ cut ( 50 C, 50 R, 50 T): this cut type is similar to pivoted or type ‘B’ cut ( 45 C, 45 R, 45 T) but the second cut is a complete axial cut splitting the split boot layer into two physically separate split boot layer halves ( 75 ) of substantially equal size.
[0169] Even though three split boot layers do not always necessarily be used, however for simplicity without compromising effectiveness, only 3-split boot layer multiple-layered laminated split boot layer assembly system ( 90 ) examples will be used throughout this patent application for my revolutionary, laminated multiple-layered, split boot layer assembly system.
[0170] The first split boot layers ( 5 C, 5 R, 5 T) can be of the regular thickness layer ( 108 ) as the rest of the split boot layers. However, to help with split boot layer installation, the first split boot layer can be substantially more rigid and consequently sturdier. Two ways to make it more rigid is either by using sturdier material or by thicker layer ( 110 ) to be form-keeping, whereby functioning as a base foundation for all the subsequent additional upper-layer split boot layers ( 10 C, 10 R, 10 T), and ( 15 C, 15 R, 15 T) to build upon. The base foundation can also be a temporary, thicker foam CV boot. All split boot layers will then be fit glove-like, sock-like, socked, stacked and layered snuggly, dovetail like, each upper-layer split boot layer on top of the lower-layer split boot layer ( 145 ). In all our examples, we will use only thicker layer for sturdier effect, without ruling out the other possibility of use of sturdier material, instead.
[0171] Since three split boot layers will be snuggly layered one over another to be socked, gloved, dove tailed over, integrated, laminated and glued together, the upper-layer split boot layer ( 150 ) should be slightly substantially proportionally larger than lower-layer split boot layer ( 145 ). That explains why the drawings show substantially different sizes of split boot layers. Either the lower-layer split boot layer ( 145 ) is appropriately sized smaller than that of upper-layer split boot layer ( 150 ) or the size of all split boot layers are substantially the same. In the latter case, all those split boot layers will be flexible, stretchable, expandable enough to allow each upper-layer split boot layer to wrap snuggly around over its lower-layer split boot layer.
[0172] The present invention featuring a glue sealant-reinforced, multiple-layered laminated, split boot layer assembly system ( 90 ) is directed to many applications. Such hardware applications as guiding, steering, control, transmission or driving means as in CV (constant velocity) joint, universal joints or more generally transmission, guiding, control, push and pull mechanisms such as in hydraulic, or pneumatic actuator equipments, or rack & pinion unit, a tie rod and a piston-cylinder boots, etc. In fact, anything that may require full or partial dismantling of related parts in order to thread the part to be protected (be it a jointed coupling or axle ( 20 )) through a protective boot can benefit from the present invention. Additionally, it can still enjoy higher level of split boot integrity than other split boot products currently available on the market.
[0173] FIGS. 1A , 1 B and 1 C all show first embodiment (as in a constant velocity joint boot, a rack and pinion unit boot, and tie rod joint boot) of my glue-fastener integrated laminated and glue-reinforced multiple-layered split boot layers system ( 90 ).
[0174] The first split boot layer ( 5 C, 5 R, 5 T) encloses around the jointed coupling or device to-be-protected on axle ( 20 ). The vertical top and bottom split boot layer halves of second split boot layer ( 10 C, 10 R, 10 T), with both halves ( 75 ) next enclosing around the first split boot layer ( 5 C, 5 R, 5 T). Glue sealant adhesive coating is sandwiched in-between the first ( 5 C, 5 R, 5 T) and second ( 10 C, 10 R, 10 T) split boot layers. The third split boot layer ( 15 C, 15 R, 15 T) will be on the outside of the second split boot layer ( 10 C, 10 R, 10 T). Similar gluing together will be done with the final or the third split boot layer ( 15 C, 15 R, 15 T) enclosing around onto the second split boot layer ( 10 C, 10 R, 10 T). Utilizing the strength from reinforcing glue sealant adhesive sandwiched in-between each two split boot layers, the layers were all pressed laminated into my multiple-layered split boot layer assembly system ( 90 ).
[0175] Concerning the glue sealant adhesive coating, single glue sealant adhesive coating ( 135 ) is in-between layer glue coating on only one abutting surface areas of the two adjacent, involved split boot layers. Dual glue sealant adhesive coatings ( 140 ) is in-between layer glue coatings on both abutting surface areas of the two adjacent, involved split boot layers. Selection of either single ( 135 ) or dual glue sealant adhesive coatings ( 140 ) will depend on the need and preference of a user. Understandably, dual glue sealant adhesive coatings ( 140 ) should provide stronger bond.
[0176] Please note: in a multiple-layered laminated split boot layer assembly system ( 90 ) with flap structure ( 95 ), each split boot layer comes from the same, single physical flap structure ( 95 ). Also the adhesive sealant coating can be either pre-coated at manufacture or coated on site, meaning only at split boot layer installation. Coating can be done in many different ways of today's glue sealant adhesive application technology such as painting, spraying, or dipping, etc., just to name a few. So when the split boot layer systems are installed the single ( 135 ) or dual glue sealant adhesive coatings ( 140 ) will be sandwiched in-between those split boot layers.
[0177] The positioning of second split boot layer ( 10 C, 10 R, 10 T) is critical to achieving maximized sealing performance of an integrated, laminated split boot layer system. The rationale behind the facing or orientation of the cut ( 53 ) of current (upper-layer) split boot layer ( 150 ) with respect to that of preceding (lower-layer) split boot layer ( 145 ) is to keep those cuts as far apart as possible from each other with the help of alignment guiding mark ( 60 ), the sealing effect can then be maximized.
OPERATION—PREFERRED EMBODIMENT
[0178] As with many split boot installations, installation of my laminated multiple layered split boot system, is quite easy. Just open up along the cut ( 53 ) split line of the first split boot layer ( 5 C, 5 R, 5 T) and then enclosing around the jointed coupling or device to-be-protected on axle ( 20 ) via the split boot layer's opening ( 115 ).
[0179] If split boot layers are not already glue sealant adhesive coated from boot manufacture time (in other words, if not pre-coated), apply the glue sealant adhesive onto the surface area of one of the two split boot layers that will come into contact, pressed against and thus abutting each other. This kind of glue coating is only a single glue sealant adhesive coating ( 135 ). If preferred having dual glue sealant adhesive coatings ( 140 ), apply the glue sealant adhesive on both the inside surface area ( 80 ) of upper split boot layer ( 150 ) as well as the outside surface area ( 85 ) of lower split boot layer ( 145 ).
[0180] Avoid applying glue sealant adhesive only where it will be directly exposed to the jointed coupling or device to-be-protected on axle ( 20 ). Also avoid applying where it will eventually form the outside surface area ( 85 ), resulting in a sticky, dirt, dust collecting outer surface of the split boot layer assembly system ( 90 ).
[0181] If preferred, optionally use some temporary holding aid (like plastic coated soft metallic wire (twist tie), or a small nylon tie) tightened around the sealing sleeve ( 35 ) to temporarily hold still and more stable, the lower-layer split boot layer ( 145 ).
[0182] As stated, the positioning of second split boot layer ( 10 C, 10 R, 10 T) (as well as later the successive third split boot layer) is important to achieving maximized sealing performance of the integrated, laminated split boot layer system. We can use alignment guiding mark ( 60 ) to have the cut ( 53 ) face as far away as possible from that cut ( 53 ) of preceding split boot layer.
[0183] Enclose, embrace, sock, stack, and layer the second split boot layer ( 10 C, 10 R, 10 T) around over the first split boot layer ( 5 C, 5 R, 5 T), with attention given to the orientation of the cut ( 53 ) using the alignment guiding mark ( 60 ). In this preferred or first embodiment case, the cut ( 53 ) of the second split boot layer ( 10 C, 10 R, 10 T) is 90 angular degrees away from that of the first split boot layer.
[0184] When the first and second split boot layers are installed surrounding the axle ( 20 ), the glue sealant adhesive will be sandwiched between the multiple layers. Next, do similarly with the final or third split boot layer ( 15 C, 15 R, 15 T) to enclose and embrace around second split boot layer ( 10 C, 10 R, 10 T). The cut ( 53 ) of the third split boot layer ( 10 C, 10 R, 10 T) is also 90 angular degrees away from that of the second split boot layer.
[0185] With all three split boot layers now integrated, sealant adhesive sandwiched in-between, the present invention of multiple layered split boot layer assembly system is formed, laminated glued fastened together. At this stage, if some temporary holding aid (like plastic coated soft metallic wire (twist tie), or a small nylon tie) is used to tighten around the sealing sleeve ( 35 ) to help hold the first or preceding split boot layer still, that temporary stabilizing holding aid can now be removed. Finally, as in any boot installation, go on to install encircling clamps tightened properly at sealing sleeve ( 35 ). After sealant adhesive glue has appropriately cured and dried, the present invention of sealant adhesive glue fastener-reinforced, laminated, integrated, multiple-layered split boot layer assembly ( 90 ) is ready for use.
[0186] It is worth mentioning that at least two boot layers 18 are required to enclose the device to-be-protected on axle 20 or the like, because the opening of the first boot layer ( 5 C, 5 R, 5 T) must be sealed by the second boot layer ( 10 C, 10 R, 10 T). The third boot layer ( 15 C, 15 R, 15 T) is an option to wrap around the second boot layer ( 10 C, 10 R, 10 T) for enhancing the strength of the boot protection. In addition, the user is able to carry the individual boot layer 18 in case of the damage of the split boot. For example, the split boot is broken during off-road motor-sports, the user is able to immediately wrap the third boot layer ( 15 C, 15 R, 15 T) around the broken second boot layer ( 10 C, 10 R, 10 T) for initial boot protection. Likewise, the user is able to replace the broken split boot by discretely wrapping the boot layers 18 around the device to-be-protected on axle 20 .
[0187] Optionally, or maybe more appropriately—optimally install the lightly or loosely installed encircling reinforcing ring ( 120 ) on each trough ( 30 ). Only if there are at least 2 troughs, can the reinforcing ring ( 120 ) be meaningfully usable. In other words, most likely the tie rod application then can not use this optional feature.
[0188] It is worth mentioning that at least one of the reinforcing rings 120 can be used for encircling around each trough of the innermost boot layer, the outermost boot layer, or each boot layer to retain the boot layer in position.
DESCRIPTION—ALTERNATIVE EMBODIMENTS
[0189] There are various possibilities with regard to many different combinations and arrangements. FIGS. 2A through 17A , 2 B through 17 B and 2 C through 17 C show all the alternative embodiments, second through seventeenth embodiments (as in applications of constant velocity joint, rack and pinion unit and tie-rod control unit, respectively). The alternative embodiments are substantially similar to the first or preferred embodiment, except for different combination groupings in different orders of split boot layers with type ‘A’, ‘B’ and ‘C’ cuts and use of overlapping spiral wrap around flap structure ( 95 ).
[0190] They are very much similar to the preferred embodiment, in term of material, thickness, structure, the facing of the cut ( 53 ) to be as far as possible from that of the preceding split boot layers. Similarly, to help with split boot layer installation, the first split boot layer can be substantially more rigid and sturdier {one way is to have it sturdier is to make it thicker layer ( 110 )} to be form-keeping. With this more rigidity functioning as a base foundation lower-layer split boot layers ( 5 C, 5 R, 5 T) for all the subsequent successive additional upper-layer split boot layers ( 10 C, 10 R, 10 T), and ( 15 C, 15 R, 15 T) to build up upon. The base foundation can also be a temporary, thicker foam CV boot. Each split boot layer will fit substantially glove-like, socked, stacked and layered snuggly each upper-layer split boot layer on top of its lower-layer split boot layer.
[0191] As mentioned above, due consideration has to be taken concerning the orientation of cut ( 53 ) split line with respect to its counterpart cut ( 53 ) split line of preceding or lower-layer split boot layer ( 145 ). As stated, the upper-layer split boot layer ( 150 ) has to be positioned with cut ( 53 ) split line lined up as far away as from that of the lower-layer split boot layer underneath to achieve maximum possible sealing performance.
[0192] Depending on the need and preference, the glue coating can be either single glue sealant adhesive coating ( 135 ) or dual glue sealant adhesive coatings ( 140 ) as stated. In a laminated multiple-layered split boot layer assembly system ( 90 ) with overlapping spiral wrap around flap structure ( 95 ), the upper-layer or lower-layer split boot layers are what spiral around the axle ( 20 ) coming from the same, single physical flap structure ( 95 ).
[0193] FIGS. 19A through 19C , all show a laminated multiple layered split boot layer system ( 90 ) with spiral wrap around flap structure ( 95 ) in eighteenth embodiment of the present invention (as used in applications such as a constant velocity joint, rack and pinion unit and tie-rod control unit, respectively).
[0194] Imaginably, with more combination more embodiments are possible with different combination selections of cut types.
OPERATION—ALTERNATIVE EMBODIMENTS
[0195] Installing and operation of alternative embodiments (namely, second through seventeenth embodiments) of the present invention is basically similar to the first embodiment, with the exception of the eighteenth embodiment.
[0196] Installation of the last alternative eighteenth embodiment laminated multiple-layered split boot layer assembly system with overlapping spiral wrap around flap structure ( 95 ) additionally involves spiral wrapping because of overlapping spiral wrap around flap structure ( 95 ). The laminated multiple-layered split boot layer assembly system ( 90 ) with flap structure ( 95 ) having beginning flap ( 100 ) comprising regular thickness layer ( 108 ) for its entire length. The flap structure ( 95 ) can also be thicker layer ( 110 ) for a sectional length of substantially full 360 spiral angular degrees, then followed by or transitioning to thinner layer, that is regular thickness layer ( 108 ). The entire flap structure ( 95 ) eventually spiral wrap around the device to-be-protected on axle ( 20 ), terminating in ending flap ( 105 ).
[0197] The flap structure ( 95 ) can be manufactured in either clockwise or counter-clockwise spiral. It is recommended and suggested but not required to have flap structure ( 95 ) spiral wrap coiled either clockwise or anti-clockwise with respect to the rotational direction of the axle ( 20 ). This is to help prevent penetration of harmful elements (like road debris, dirt, water, etc) into the laminated multiple layered split boot layer system when the axle ( 20 ) is rotating especially in forward driving usually in high speed. The ending flap's ( 105 ) opening (glued) gap will then avoid facing the airflow generated from the rotational direction of the axle ( 20 ).
[0198] The ending flap ( 105 ) forms the outside surface area ( 85 ) of the split boot layer system, while beginning flap ( 100 ) forms the inside surface area ( 80 ). Additionally, the glue sealant adhesive coating ( 130 ) will then be sandwiched in-between the laminated multiple split boot layers, which will then be reinforced and laminated into a multiple-layered laminated split boot layer assembly system ( 90 ).
[0199] Where the overlapping spiral wrap around flap structure ( 95 ) transitions in firmness or sturdiness, say from thicker layer ( 110 ) to become regular thickness layer ( 108 ), can be used as a guiding means for the overlapping spiral wrap around flap structure ( 95 ) to spiral wrap around. Starting with the beginning flap ( 100 ) being the thicker layer ( 110 ) of substantially full 360 spiral angular degrees makes a firm, sturdier base first split boot layer. The first split boot layer ( 5 C, 5 R, 5 T) can now be a base for further spiral wrapping tight around the axle ( 20 ) of the remaining thinner portion of the flap structure ( 95 ) as shown in FIGS. ( 31 A, 31 B, 31 C) ending with the ending flap ( 105 ).
[0200] As with the first or preferred embodiment of my invention, for all alternative embodiments, the decision to use single glue sealant adhesive coating ( 135 ) or dual glue sealant adhesive coatings ( 140 ) is up to the user.
[0201] Accordingly, the reader will see that, with my invention, I have provided an easy installation dust protection boot enclosure mean without compromising the required and crucial high-sealing reliability, substantially as good as the regular and good old traditional non-split dust protection boot as in the examples of a constant velocity joint boot, a rack and pinion column boot, tie-rod joint boot, and other similar devices, etc., like for example hydraulic push and pull piston-cylinder assembly. Whereas the overlapping spiral wrap around flap structure ( 95 ) transition from thicker layer ( 110 ) to become regular thickness layer ( 108 ) in one step, instead it can also be a gradual thickness transition tapering from thicker layer starting at beginning flap ( 100 ) to thinner layer at ending flap ( 105 ) for the overlapping spiral wrap around flap structure ( 95 ) to spiral wrap around.
[0202] While the above description contains many specificities, these should not be construed as limitations on the scope of the invention, but as exemplifications of the presently preferred embodiments thereof. Many other ramifications and variations are possible within the teachings of the invention. For example, instead of the current examples of using just three split boot layer for the laminated multiple-layered split boot layer assembly system ( 90 ), it can be less or more than three layered split boot layer assembly. With more split boot layers, it will mean more combinations are possible than what are shown herein. Also instead of just glue sealant adhesive as reinforcement, mechanical fasteners such as screws, bolts, rivets or nails, etc. can also be used, as newer technology substitute reinforcements become available.
[0203] One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.
[0204] It will thus be seen that the objects of the present invention have been fully and effectively accomplished. The embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims. | A laminated multiple-layered split boot layer assembly, providing both very important qualities of easy installation and reliable boot sealing performance. Easy installation is easy to achieve but the reliable boot sealing performance of substantially high degree of reliable boot sealing performance is very much needed but has eluded many inventors until now. Many different solutions and approaches are used, such as multiple layering, reinforcement with fastener such as glue sealant adhesive, reinforcement encircling rings, and appropriately positioning each split boot layer's cut ( 53 ) split line, in relationship to the cut ( 53 ) of preceding and adjacent split boot layer for maximized sealing performance. | 5 |
FIELD OF THE INVENTION
The present invention relates generally to high-speed printing systems and more particularly to a system and method for controlling distortion in a high-speed printing system.
BACKGROUND OF THE INVENTION
In high-speed inkjet systems with high-tension webs, the substrate may experience significant stretching and distortion as a result of the absorption of the ink while the web is under tension. For example, when the web is paper, the distortion and stretching causes noticeable image distortion errors between the color planes of a multi-component system. With some inkjet systems, the resulting image distortion has caused significant customer satisfaction problems, and (along with other significant factors) has led some customers to reserve the printer for one-component printing. Furthermore, drying of the ink during processing causes the paper to shrink, and subsequent component printing causes the paper to stretch again. Stretching may be different in the “scan” direction (i.e., perpendicular to the direction of travel of the web) than in the “process” direction (i.e., the direction of travel of the web) because of the tension in the web. Since the ink content of the components can differ greatly, the degree of stretching or distortion may differ between printing stations.
Conventional inkjet systems have had significant problems with web distortion, which have been addressed mechanically with custom unwinders. The custom unwinder is costly, but its primary shortcoming is that it is not part of a closed-loop system. Specifically, the unwinder does not measure local stretching of the web and adjust its work appropriately.
Furthermore, the unwinder works at only the entry point of the system, so that non-uniform distortion along the process direction cannot be addressed.
Accordingly, what is needed is a system and method for overcoming the above-identified problems. The present invention addresses such a need.
SUMMARY OF THE INVENTION
A method and system for a printing device is disclosed. The method and system comprise printing a test pattern on a print medium and generating a digital image of the printed test pattern by an imaging device. The method and system include analyzing an interference pattern to measure for distortion of the print medium and calibrating the printing device based upon the measured distortion.
In a preferred embodiment, the present invention utilizes the reticle patterns, which are printed in the margins of the paper, which are measured real-time during printing. The interference or Moiré patterns created by superimposed reticles may be used to measure image distortion, process direction misalignment, and misregistration caused by web distortion. The advantage of this invention is that image distortion compensation, RIP (Raster Image Processor) parameters, timing, or other printer characteristics may be adjusted on-the-fly in a closed feedback system, for high-speed textile or paper color printing, utilizing on-the-fly distortion or stretch measurement for accurate color and/or duplex images registration. In a duplex printer, automatic image alignment front-to-back is obtained by combining optically or logically the two images for the evaluation of interference patterns and amount of distortion in the process and scan direction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a block diagram of a printing environment in which certain described aspects of the invention are implemented;
FIG. 2 illustrates a block diagram of software elements, hardware elements, and data structures in which certain described aspects of the invention are implemented;
FIG. 3 illustrates logic implemented in an application to configure a print system in accordance with certain described implementations of the invention;
FIG. 4 illustrates logic implemented in an application for color image distortion compensation of a printer in accordance with certain described implementations of the invention; and
FIG. 5 illustrates logic implemented in an application to indicate how color image distortion compensation of a printer is performed while printing a print job in accordance with certain described implementations of the invention.
DETAILED DESCRIPTION
The present invention relates generally to high-speed printing systems and more particularly to a system and method for controlling distortion in a high-speed printing system. The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the preferred embodiment and the generic principles and features described herein will be readily apparent to those skilled in the art. Thus, the present invention is not intended to be limited to the embodiment shown but is to be accorded the widest scope consistent with the principles and features described herein.
FIG. 1 illustrates a block diagram of a printing environment in which certain described aspects of the invention are implemented. A printer 100 includes one or more printing stations 102 . The printing stations 102 may include a cyan printing station 102 a , a magenta printing station 102 b , a yellow printing station 102 c , and a black printing station 102 d , capable of printing with cyan, magenta, yellow, and black inks or toners respectively.
The printer 100 may be any multi-component printer known in the art including an electrostatic printer, an inkjet printer, a laser printer, a plotter, a network printer, a stand-alone printer etc. Alternative implements may use other devices that function in a manner analogous to printers such as digital duplicating machines, photocopiers, fax machines etc. While the current implementation describes a four-component printer, in alternative implementations printer 100 could be a two- or three-component printer.
Printer 100 could also be a single component printer, if each of at least two single component printers prints one color component. Also, printer 100 could be a single component printer where the reticle-based method is used for ink jet alignment within the print head.
While FIG. 1 shows four printing stations 102 a , 102 b , 102 c , and 102 d , there may be fewer or more printing stations in alternative implementations. In some implementations, the black printing station 102 d may be omitted. The printing stations 102 a , 102 b , 102 c , 102 d may also print with inks or toners different from cyan, magenta, yellow and black. While the printing stations 102 a , 102 b , 102 c , 102 d are indicated within separate blocks in FIG. 1 the printing stations 102 a , 102 b , 102 c , 102 d may be constructed as a single hardware unit or as multiple hardware units. If the printing stations are constructed as a single hardware unit, the single hardware unit may at different times print with a different colored ink or toner.
Printer 100 may also include a controller 104 coupled to a computational unit 106 . The computational unit 106 may be any computational unit known in the art, including a processor 106 a and memory 106 b . The computational unit 106 may be inside or outside the printer 100 . The memory 106 b may include volatile memory 107 a such as RAM or non-volatile memory 107 b such as disk storage. The controller 104 may be implemented in several ways including software, hardware or a combination of software and hardware. The controller 104 may lie within or outside the computational unit 106 . In one implementation the controller 104 works cooperatively with the computational unit 106 . In some implementations, software or hardware present with or within the printer 100 may absorb the functions of the controller 104 .
The controller 104 may be able to calibrate the printing stations 102 , a print media supply 108 and a print media cutter 110 , and other components of the printer 100 not shown in FIG. 1 . The controller 104 may adjust the timing of the firing of the printing stations 102 , to compensate for distortion in a printed color plane. The controller 104 may also perform pixel shifts as part of rasterization, i.e. the controller 104 may shift a color plane an integral and/or fractional number of pixels in memory before printing the color plane.
The print media supply 108 may include a collection of any type of print medium 108 a known in the art on which the printer 100 is capable of printing, including paper, transparencies, fabric, glass, plastic, labels, metal, cardboard, etc. The print medium 108 a may also be a container made up of a variety of material, including plastic, cardboard, metal etc. In one implementation the print medium 108 a is a roll of paper. The print medium 108 a passes through the cyan, magenta, yellow, and black printing stations 102 a , 102 b , 102 c , 102 d . Subsequently, the print media cutter 110 may crop parts of the print medium 108 a.
A scanning device 112 is coupled to the printing stations 102 and the computational unit 106 . The scanning device 112 may include any scanning device known in the art, including a charge coupled device (CCD) camera, a scanner, or any other imaging device capable of digitizing images printed on the print medium 108 a . The scanning device 112 can image the print medium 108 a as the print medium 108 a moves through the printing stations 102 . While FIG. 1 shows only one scanning device, in alternative implementations multiple scanning devices may be positioned to scan the outputs of the cyan, magenta, yellow, and black printing stations 102 a , 102 b , 102 c , 102 d . In the current implementation, the scanning device 112 scans the print medium 108 a after the four printing stations 102 a , 102 b , 102 c , 102 d have printed on the print medium, i.e. a page is scanned after the printer 100 has overlaid all color planes on the page.
An application 114 coupled to the printer 100 may implement aspects of the invention. While the application 114 has been shown in a separate block outside the printer 100 , part or all of the functions of the application 114 may be integrated into the computational unit 106 , into the controller 104 or into any other unit not illustrated in FIG. 1 such as a printer driver resident on a computational device outside the printer 100 .
FIG. 2 illustrates a block diagram of software elements, hardware elements, and data structures in which certain described aspects of the invention are implemented. Referring to FIGS. 1 and 2 together, a reticle pattern 200 is a predetermined marking pattern that is capable of being printed at an appropriate location on the print medium 108 a by the printing stations 102 . Further details of reticle patterns are described in the publication “Reticles in Electro-Optical Devices” (copyright 1966 by Lucien M. Biberman), which publication is herein incorporated by reference.
The scanning device 112 is capable of digitizing the reticle pattern 200 printed on the print medium 108 a and can produce a digital image of the reticle pattern 202 . When the printer 100 prints the reticle pattern 200 onto the print medium 108 a , if there is color image distortion or reticle image distortion on the printer 100 , the printed reticle pattern 200 may have interference patterns, such as Moiré patterns. The test patterns are patterns of light and dark lines, and the interference patterns appear when two repetitive patterns of lines, circles, or arrays of dots overlap with imperfect alignment. Interference patterns magnify differences between two repetitive patterns. If two patterns are exactly lined up, then no interference pattern appears. The misalignment of two patterns will create an easily visible interference pattern. As the misalignment increases, the lines of the interference pattern appear thinner and closer together. Interference patterns are well known in the art and some applications of interference patterns in imaging are described in the doctoral dissertation “Analysis and reduction of Moiré patterns in scanned halftone pictures” (May 1996, Virginia Polytechnic Institute and State University). In the implementation, interference patterns may arise because the printer 100 prints the same reticle pattern 200 by overlaying ink or toner from at least two of the cyan, magenta, yellow, and black printing stations 102 a , 102 b , 102 c , and 102 d respectively. Interference patterns may appear prominently when reticle patterns have comparable intensity values in the different color planes.
FIG. 2 also illustrates a digital image analyzer unit 204 , where the digital image analyzer unit 204 is capable of processing the digital image of the reticle pattern 202 and extracting a digital image of interference pattern 206 corresponding to the digital image of the reticle pattern 202 . The digital image analyzer unit 204 may include an edge detector 204 a that determines edges by applying prior art edge detectors such as the Sobel operator, Canney edge operator or other image gradient-based operators to the digital image of the reticle pattern 202 . The digital image analyzer unit 204 and the edge detector 204 a may be implemented in hardware or software, or via a combination of hardware and software.
A distortion error analyzer 208 is capable of processing the digital image of interference pattern 206 and producing distortion adjustment control instructions 210 . Analysis of patterns obtained from reticle patterns is well known in the art and described in the publication “Reticles in Electro-Optical Devices” (copyright 1966 by Lucien M. Biberman). The distortion adjustment control instructions 210 are instructions for adjusting the components of the printer 100 , such as the printing stations 102 and the print media supply 108 , that reduces the distortion.
The controller 104 may be capable of processing the distortion adjustment control instruction 210 , and may produce printing station adjustment instructions 214 to adjust the printing stations 102 . The newly adjusted printing stations 102 may print the reticle pattern 200 on the print medium 108 a.
FIG. 3 illustrates logic, implemented in an application 114 of FIG. 1 , coupled to the printer 100 to configure the printer 100 in accordance with an implementation of the invention. As stated earlier, the application 114 may reside within the printer 100 or may reside in an external computational device outside of the printer 100 and from the external computational device control the printer 100 . Referring to FIGS. 1 , 2 , and 3 together, at block 302 , the application 114 enables an entity (such as an operator, a programmer, a computer program, a predetermined data file etc.) to enter predetermined reticle patterns 200 , where each of the reticle patterns 200 may optionally be associated with one or more printing stations 102 . The application 114 stores (at block 304 ) the reticle patterns 200 in the non-volatile memory 107 b . The application 114 may then enable the entity to enter (at block 306 ) a predetermined periodicity of printing of each reticle pattern 200 . The periodicity of printing of each reticle pattern 200 may depend on how frequently printer 100 has to adjust for distortion. At block 308 , the application 114 stores the periodicity of printing of the reticle patterns 200 in the non-volatile memory 107 b.
The application 114 may then enable the entity to enter (at block 310 ) the predetermined positions on print medium 108 a for printing each reticle pattern 200 . Control proceeds to block 312 , where the printer 100 stores the positions in non-volatile memory 107 b . Control proceeds to block 314 where the print system configuration ends.
In alternative implementations, the entire logic of FIG. 3 may be preprogrammed such that no entity has to provide any input or predetermine any values. The entire system may come pre-programmed with default reticle patterns, values for periodicity of printing, and positions on print medium for printing each reticle pattern.
FIG. 4 illustrates logic implemented in the application 114 of FIG. 1 for minimizing image distortion from the printer 100 in accordance with implementations of the invention, referring to FIG. 1–4 together. The application 114 starts at block 400 , and the application 114 prints (at block 402 ) a reticle pattern 200 on one part of the print medium 108 a via the printing stations 102 . The application 114 may print user requested data on the other parts of the print medium 108 a . The scanning device 112 scans the digital image and generates (at block 404 ) a digital image of the reticle pattern 202 . At the conclusion of block 404 , control passes in parallel to blocks 408 and 406 . At block 408 , the printer 100 ejects the page. The reticle pattern may be removed by post-processing equipment such as the print media cutter 110 . The post processing equipment may process a job much later than the original printing. For example, the printed medium may be re-rolled after printing, stored somewhere, and postprocessed later. In alternate implementations, the reticle pattern may also be removed from the print medium 108 a without using the print media cutter 110 , such as for example by overprinting the reticle pattern with the same color on the print medium, or in any other manner known in the art.
Parallel to the execution of block 408 , control proceeds to block 406 from block 404 . At block 406 , the digital image analyzer unit 204 processes the digital image of the reticle pattern 202 and isolates a digital image of an interference pattern 206 . Control proceeds to block 410 , where the distortion error analyzer 208 compares the digital image of the interference pattern 206 with the reticle pattern 200 . The distortion error analyzer 208 determines (at block 412 ) if the printer 100 needs to make adjustments to minimize distortion. If no distortion adjustments are needed, control proceeds to block 414 and the process comes to a stop.
If at block 412 , the distortion error analyzer 208 determines that distortion adjustments are needed, control proceeds to block 416 where the distortion error analyzer 208 generates distortion adjustment control instructions 210 .
Control proceeds to block 418 , where the application 114 adjusts the printing stations 102 . While the printing stations 102 may be adjusted in several ways, in one implementation the distortion error analyzer 208 sends the distortion adjustment control instructions to the controller 104 and the controller 104 adjusts the printing stations 102 by generating printing station adjustment instructions 214 .
Control proceeds to block 402 , and a control loop formed by blocks 404 , 406 b , 410 , 412 , 416 , 418 may be repeated. Within the control loop the application 114 repeatedly adjusts the printer 100 until no further distortion adjustments are needed. The application 114 may periodically execute the logic of FIG. 4 depending on how often distortion adjustment is required for the printer 100 .
The printer does not have to stop printing during distortion adjustments. For example, with reference to FIG. 4 , while the printing station 102 is being adjusted at block 418 , the reticle patterns 200 may be ejected (at block 408 ) from the printer 100 . Alternatively, the reticle patterns 200 may be printed in area of the media that may not be visible, may be cropped later or may be part of the desired print area. Additionally, printed media may be rejected until distortion is minimized.
FIG. 5 illustrates logic implemented in an application to indicate how distortion adjustment of a printer is performed while printing a print job in accordance with certain implementations of the invention, referring to FIGS. 1 and 5 together. At block 500 , the application 114 starts processing a print job. After the application 114 processes (at block 502 ) part of the print job, the application 114 performs (at block 504 a ) distortion adjustment of the printer and optionally concurrently processes (at block 504 b ) part of the print job. Control proceeds to block 506 , at the conclusion of either of blocks 504 a or 504 b , where the application 114 determines if the print job is complete. If so, the application 114 stops (at block 508 ) the processing of the print job. If at block 506 , the application 114 determines that the print job is incomplete, control passes to block 502 , and the logic of blocks 502 , 504 a , 504 b , and 506 are repeated.
The method, system, and article of manufacture can perform distortion adjustment on a printer on-the-fly. In this way, the printer is adjusted while printing the print job, such that the distortion measured on a printed page is used to adjust the printer when printing subsequent pages of the print job. Additionally, the periodicity of printing of reticle patterns may be adjusted depending on how frequently printing stations need to be adjusted for distortion. By performing periodic adjustments of the printing station while printing, a printer may print very long print jobs continuously without the intervention of a human operator. The interference patterns provide enough details to adjust the printer to minimize distortion.
ADDITIONAL IMPLEMENTATION DETAILS
The described techniques for distortion adjustment may be implemented as a method, apparatus or article of manufacture using standard programming and/or engineering techniques to produce software, firmware, hardware, or any combination thereof. The term “article of manufacture” as used herein refers to code or logic implemented in hardware logic (e.g., an integrated circuit chip, Programmable Gate Array (PGA), Application Specific Integrated Circuit (ASIC), etc.) or a computer readable medium (e.g., magnetic storage medium, such as hard disk drives, floppy disks, tape), optical storage (e.g., CD-ROMs, optical disks, etc.), volatile and non-volatile memory devices (e.g., EEPROMs, ROMs, PROMs, RAMs, DRAMs, SRAMs, firmware, programmable logic, etc.). Code in the computer readable medium is accessed and executed by a processor. The code in which implementations are made may further be accessible through a transmission media or from a file server over a network. In such cases, the article of manufacture in which the code is implemented may comprise a transmission media, such as a network transmission line, wireless transmission media, signals propagating through space, radio waves, infrared signals, etc. Of course, those skilled in the art will recognize that many modifications may be made to this configuration without departing from the scope of the implementations, and that the article of manufacture may comprise any information bearing medium known in the art.
While the implementations have been described with respect to analysis of interference patterns, such as Moiré patterns, analysis of other patterns similar to interference patterns, or patterns caused via phenomenon or principles similar to interference may also be used. Furthermore, the implementations analyze the interference patterns after all the printing stations have laid down the color planes. In alternative implementations, the scanning device may scan the printed reticle patterns in between printing stations, and secure additional clues for minimizing distortion of the printer. The reticle pattern may also be printed on media to be used for distortion adjustment at a later time and even at a different location.
The implementations of FIGS. 3 and 4 describe specific operations occurring in a particular order. Further, the steps may be performed in parallel as well as sequentially. In alternative embodiments, certain of the logic operations may be performed in a different order, modified or removed and still implement preferred embodiments of the present invention. Morever, steps may be added to the above described logic and still conform to the preferred embodiments.
Variations of the implementations may be constructed for various types of printing devices. For example, in an ink-jet printer the implementation may include reticle patterns that generate interference patterns only if the ink spots printed by an ink-jet printer are small enough not to bleed into each other. In such a case the implementation would attempt to secure interference patterns rather than eliminate interference patterns in the digital image of the reticle pattern. Manual or automatic adjustments may be made to the ink-jet printer, if the spots are judged to be bleeding too much.
Alternatively, the presence of the interference patterns may be used as a security feature on printed materials such as legal documents or currency, where the presence of a correct interference pattern is used to validate the legitimacy of the printed matter. Because only the superimposed reticles, with resulting interference pattern, will be present on the final printed matter, additional security is maintained, since counterfeiters will not have easy access to the original reticle patterns used to create the interference patterns.
In variations of the implementation the calibration may be performed at a later time or at a location different from the printing device. In some printers, a color head on a printing station may comprise of a multiple head array, where each head of the multiple head array may have alignment errors. In one implementation, reticle patterns that cover most of a page may be used to provide diagnostics on each head of the multiple head array. The scanning device may be movable such that the scanning device can be moved over the reticle patterns to return diagnostics as to which heads in the multiple head array are providing the distortion, and to suggest a direction for correction.
The implementation can have a test pattern of interference patterns that cover most of the page to give diagnostics on each of the head arrays. The implementation can have the CCD or scanner that reads the interference patterns be moveable.
The implementation could also include a test pattern of interference patterns, either whole page or across the scan width, so that scan direction distortion of the paper can be measured and adjusted for on a component-by-component basis. The whole pages are used for calibration, where the single-line or-column interference patterns are used for on-the-fly adjustment. Furthermore, rather than a whole “scan line” of interference patterns, one interference pattern can be used at each side (and potentially between pages for n-up configurations) to do coarse measurement of the scan direction distortion, based on the assumption that the distortion is uniform. Since scan direction distortion is going to be less than process direction distortion (because the web is under higher tension in the process direction), the assumption of uniformity is probably sufficient for measurement of scan direction.
A whole scan line of interference patterns can be used to measure and compensate for local changes in distortion; i.e., where distortion is not uniform across the entire scan width, but varies within a print job.
The implementation could allow ink jet printers to have an interference pattern for the test pattern that can indicate if a single jet is out. Interference patterns can be printed in areas where they do not need to be removed, e.g., where they will be hidden by binding or other processing.
In another embodiment, the interference patterns could be used to build a model to assist with on-the-fly or preRIP adjustment. Measured information could be used to develop a model for a closed-loop feedback system for predicting the stretch for this particular paper based on the component coverage (e.g., by pel counting). This can be used to reduce the amount of on-the-fly calculation required.
This model can also be used in preRIP if the paper is known to be the same as the paper used in the model-building run, and if the job coverage/content is known to be comparable to that of the model-building run. This is particularly useful where a job does not need careful image distortion compensation, and where the run performance of the printer is more critical. If content/coverage/paper/environment may have changed “somewhat” from the measurement run, this information in preRIP can be used to bring the print “closer to feedback loop lock” for the on-the-fly adjustment. Model information can be part of the forms definition, for example.
Interference patterns can be used in calibration pages to precalibrate for the paper. Then one may use the prebuilt model to preRIP the data. These interference patterns can be laid out or chosen in such a way to emulate the range of coverage of jobs; e.g., light-to-heavy coverage. They can also be chosen and placed to emulate the actual layout of the non-variable parts of the actual job.
A checksums on overlay projects could be stored, tied to distortion models and form definitions. When the checksum recurs, the distortion model can be pulled up. These stored checksums can be expired out of the database over time if not referenced again, or not stored at all unless the overlay occurs some threshold number of times. For paper with preprinted marks or pinholes, the measured information can be combined with this information to produce a more accurate model. This is also applicable to other printing technology that has not dealt with distortion of the paper, e.g., due to fusing of wet papers on EP technologies.
The present invention could be utilized for applications such as statements, books, or digital newspaper where the image must be registered, but the image distortion of the (usually single-component) text is not important. Thus, only the image is adjusted on-the-fly or pre-adjusted in preRIP, based on the measured or model information.
Although the present invention has been described in accordance with the embodiments shown, one of ordinary skill in the art will readily recognize that there could be variations to the embodiments and those variations would be within the spirit and scope of the present invention. Accordingly, many modifications may be made by one of ordinary skill in the art without departing from the spirit and scope of the appended claims. | A method and system for a printing device is disclosed. The method and system comprise printing a test pattern on a print medium and generating a digital image of the printed test pattern by an imaging device. The method and system include analyzing an interference pattern to measure for distortion of the print medium and calibrating the printing device based upon the measured distortion.
In a preferred embodiment, the present invention utilizes the reticle patterns, which are printed in the margins of the paper, which are measured real-time during printing. The interference or Moiré patterns created by superimposed reticles may be used to measure image distortion, process direction misalignment, and misregistration caused by web distortion. The advantage of this invention is that image distortion compensation, RIP (Raster Image Processor) parameters, timing, or other printer characteristics may be adjusted on-the-fly in a closed feedback system, for high-speed textile or paper color printing, utilizing on-the-fly distortion or stretch measurement for accurate color and/or duplex images registration. In a duplex printer, automatic images alignment front-to-back is obtained by combining optically or logically the two images for the evaluation of interference patterns and amount of distortion in the process and scan direction. | 1 |
BACKGROUND OF THE INVENTION
This is a continuation division of application Ser. No. 07/792,435, filed Nov. 15, 1991, abandoned, which is a continuation-in-part of application No. 07/525,162 filed May 16, 1990, now abandoned, which in turn is a continuation-in-part of application No. 07/363,496 filed Jun. 8, 1989, now abandoned.
FIELD OF THE INVENTION
This invention relates to a method for making heat exchangers, and in particular, to automotive oil coolers which are located inside other heat exchangers, such as automotive radiators.
In motor vehicles, it is common to provide heat exchangers for cooling engine oil or transmission fluid. Due to the heat transfer characteristics of oil, liquid cooled heat exchangers are normally used as opposed to air cooled exchangers. The most convenient way to do this is to mount the oil cooler or heat exchanger inside the cooling system of the motor vehicle, and in particular, inside the radiator.
In the past, the oil coolers of the type in question which have been mounted inside automotive radiators have consisted of concentric tubes closed at both ends to form an internal passage for the oil. The engine coolant flows around the outside tube and through the inside tube. A difficulty with this type of oil cooler, however, is that it is relatively ineffective per volume of radiator occupied.
SUMMARY OF THE INVENTION
The present invention is a plate type heat exchanger which is more effective per volume of radiator occupied, and yet is strong enough to withstand the high oil pressures that are frequently encountered in such engine oil or transmission fluid cooling systems.
According to the invention, there is provided a heat exchanger comprising a plurality of stacked plates arranged in face-to-face pairs, each of the face-to-face pairs including first and second plates. The first plate has a planar central portion, a raised peripheral co-planar edge portion extending above the central portion, and opposed co-planar end bosses extending below the central portion. The second plate of each face-to-face plate pair has a peripheral edge portion joined to the first plate peripheral edge portion, a central portion spaced from the first plate central portion, and opposed coplanar end bosses extending above the second plate central portion. The first and second plate central portions have opposed cladding layers formed thereon. A planar turbulizer is located between the first and second plate central portions of each face-to-face plate pair, the thickness of the turbulizing is being greater than the distance between the opposed cladding layers of the first and second plate central portions. The first and second plate central portions have a plurality of spaced-apart outwardly disposed dimples formed therein, the dimples extending equidistant with the end bosses. The first plate of one plate pair is located back-to-back with the second plate of an adjacent plate pair, the respective dimples and end bosses being joined together. Also, each plate pair defines inlet and outlet openings for the flow of fluid through the plate pair past the turbulizer.
According to yet another aspect of the invention, there is provided a method of making a heat exchanger comprising the steps of providing a plurality of plates each having a planar central portion, a raised peripheral edge portion, a brazing cladding layer formed on the plates and inlet and outlet openings formed therein. The plates are arranged face-to-face into pairs having a hollow space therebetween. A turbulizer is inserted into the hollow space, the turbulizer being in contact with the planar central portions of each plate of a plate pair and of a thickness generally equal to the distance between the planar central portions without the cladding layers formed thereon. A plurality of said face-to-face plate pairs is stacked so that the inlet and outlet openings are in registration and the raised peripheral edges are separated. Also, the stacked plate pairs are heated to melt the cladding layers causing the turbulizer to be embedded in the cladding layers and the peripheral edges to be joined to form a fluid tight assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of a preferred embodiment of an in tank oil cooler according to the present invention;
FIG. 2 is an exploded perspective view of a subassembly of the oil cooler of FIG. 1;
FIG. 3 is a partial sectional view taken along lines 3--3 of FIG. 1 and showing an alternate embodiment;
FIG. 4 is a sectional view taken along lines 4--4 of FIG. 1;
FIG. 5 is an enlarged sectional view taken along lines 5--5 of FIG. 2;
FIG. 6 is an enlarged plan view taken along lines 6--6 of FIG. 2;
FIG. 7 is a partial sectional view taken along lines 7--7 of FIG. 6 but showing a plurality of stacked plate pairs prior to brazing;
FIG. 8 is partial sectional view similar to FIG. 7 but showing the stacked plate pairs after brazing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, a preferred embodiment of an oil cooler or heat exchanger is generally represented by reference numeral 10 in FIG. 1. Heat exchanger 10 is formed of a plurality of face-to-face plate pairs 12 as described in detail below with reference to FIG. 2. A top plate pair 14 has a smooth top plate 16 and a bottom plate pair 18 has a smooth bottom plate 20, although top and bottom plates 16, 20 could be dimpled as shown in FIG. 2 if desired. Heat exchanger 10 also has threaded nipples 22 swaged in place in suitable circular openings in top plate 16. One nipple 22 serves as an inlet and the other nipple 22 serves as an outlet for the flow of oil, such as engine oil or transmission fluid through heat exchanger 10.
Referring in particular to FIG. 2, a typical face-to-face plate pair 12 is shown in an exploded perspective view. Plate pair 12 includes a first or bottom plate 24 and a second or top plate 26. First plate 24 has a planar central portion 28, and a raised peripheral, co-planar edge portion 30 which extends above or is located in a plane above central portion 28. First plate 24 also includes opposed, co-planar end bosses 32 extending below or located at a lower level than central portion 28. For the purposes of this disclosure, the term "co-planar" is intended to mean being in a plane parallel to the plane of central portion 28.
In the preferred embodiment, the first and second plates 24, 26 are identical, so the terms "below" and "above" with reference to the central portion 28 of first plate 24 would, of course, be reversed with reference to the central portion 28 of second plate 26 as seen in FIG. 2.
The ends of plates 16, 20, 24 and 26 are rounded and end bosses 32 of plates 24, 26 are formed with "D"-shaped openings 34, although any shaped opening could be used if desired. The "D"-shaped openings 34 have an opening edge portion 35 located around "D"-shaped openings 34. As mentioned above, smooth top plate 16 has circular openings to accommodate nipples 22. The smooth bottom plate 20 has no openings formed therein.
First and second plates 24, 26 are formed with a plurality of spaced-apart dimples 36 formed therein. With reference to first plate 24, dimples 36 extend below the central portion 28 equidistant or to the same planar level as end bosses 32, so that when two of the plates 24, 26 are located back-to-back as seen best in FIG. 3, the respective dimples 36 and end bosses 32 are joined together along a common plane.
A turbulizer 38 is located inside each face-to-face plate pair 12, including top and bottom plate pairs 14, 18. Turbulizer 38 is a strip of expanded metal. The preferred configuration is parallel rows shaped in a sinusoidal, staggered configuration, although other configurations could be used as desired. The length of turbulizer 38 corresponds with the length of the plate central portions 28, and the width of turbulizer 38 corresponds with the distance between peripheral edge portions 30. The thickness of turbulizer 38 is such that after the plate pairs are assembled and heat exchanger 10 is joined together, such as by brazing, the plate central portions 28 are joined to and in good thermal contact with turbulizer 38, as discussed further below.
Dimples 36 are spaced uniformly over the plate central portions 28. One of the primary functions of dimples 36 is to support the plate central portions 28 and prevent these central portions from sagging when the plates are heated to brazing temperatures. Central portions 28 must be kept flat and in full contact with turbulizer 38 during the brazing process in order to obtain good thermal contact between the turbulizer and the plates. Another function of the dimples is to cause some turbulence in the coolant thereby increasing the heat transfer capabilities of the heat exchanger. When the plates are in back-to-back arrangement dimples 36 maintain the back-to-back plates in spaced apart relation so that the coolant would have an effective path between the back-to-back plates. The height of dimples 36 should be optimized in that the dimples should be tall enough to allow the coolant to flow between the back-to-back plates but not too tall because of the overall size of heat exchanger 10 should be minimized where possible.
Dimples 36 preferably are large enough to result in flat top surfaces to give a good joint between mating dimples 36. As seen best in FIGS. 3 and 4, the radius of the shoulders in the dimples should be such that sharp corners should be avoided or the dimples could break out as a result of high pressures in heat exchanger 10.
Dimples 36 should also not be too large in diameter, because the surface area of central portion 28 occupied by dimples 36 is area that is not in contact with turbulizer 38 and this detracts from the heat transfer efficiency of heat exchanger 10. It will be apparent to those skilled in the art that the number and size of the dimples 36 should be chosen so that sufficient strength and structural support for the plate central portions is provided during the brazing process, and so that the gain in heat transfer efficiency through turbulence in the coolant is balanced against loss of heat transfer efficiency by making the dimples too numerous or too large. It has been found that for plates with central portions 28 of approximately four centimetres in width, dimples that are 0.5 centimetres in diameter and spaced-apart longitudinally about 2.5 to 3.0 centimetres and transversely about 2 to 3 centimetres provides a preferred balance where aluminum of 0.07 to 0.08 centimetres thickness is used for the plates.
Referring to FIG. 2, plates 24, 26 may be formed with inner tabs 42 extending transversely from opening edge portion 35. Inner tabs 42 are located at only one end of each plate so that upon assembly, inner tabs 42 on one plate such as first plate 24 are crimped over the opening edge portion 35 of the mating plate 26, when the plates are in a back-to-back arrangement to form a back-to-back plate pair 44. This prevents the plates of each back-to-back plate pair 44 from moving longitudinally or transversely relative to each other. Inner tabs 42 are not necessary, however, and may be eliminated if alignment of the plate pairs is not a problem.
Referring again to FIG. 2, plates 24, 26 are formed with peripheral tabs 40 at opposed ends. Peripheral tabs 40 are located at respective diametrically opposed "corners" of each plate, so that upon assembly, the peripheral tabs 40 on one plate, such as first plate 24, are crimped over the peripheral edge portion 30 of the mating plate, such as second plate 26, when the plates are in face-to-face arrangement to form face-to-face plate pair 12 as seen best in FIG. 1. This prevents the plates of each face-to-face plate pair 12 from moving longitudinally or transversely relative to each other. Again, peripheral tabs 40 are not necessary and may be eliminated if alignment of the plates is not a problem.
In an alternate embodiment shown in the left hand portion of FIG. 3, the inner tabs 42 can be used to maintain the first and second plates, of the back-to-back plate pairs in alignment, without crimping over the inner tabs 42. Similarly the peripheral tabs 40 can be used to maintain the first and second plates of the face-to-face plate pair in alignment without crimping over the peripheral tabs 40. It will be apparent to those skilled in the art that the peripheral tabs 40 and the inner tabs 42 may be used to align the stacked plates or to mechanically attach the plates as desired. The heat exchanger can be further modified by eliminating the peripheral tabs 40 and inner tabs 42 and stacking plates in the pattern described above and shown in FIG. 3.
In the preferred embodiment, aluminum is used for all of the components of heat exchanger 10. Nipples 22 and turbulizer 38 are formed of aluminum alloys, and plates 16, 20, 24 and 26 are formed of brazing clad aluminum, which is aluminum that has a lower melting point cladding or aluminum brazing alloy layer 50 on the outer surfaces, as seen best in FIGS. 5, 7 and 8 the cladding layers 50 are each about 8 to 10 per cent of the thickness of the plate.
As seen best in FIGS. 7 and 8 the thickness of turbulizer 38 is generally equal to the distance between the first and second plate central portions 28 without cladding layers 50. In other words, the thickness of turbulizer 38 is greater than the distance between the opposed cladding layers 50 of the first and second plate central portions 28 after final assembly. The reason for this is that as these cladding layers 50 melt during the brazing process, all of the high areas of turbulizer 38 are embedded in the cladding layers 50 and turbulizer 38 is brazed to the plate central portions 28 with good thermal heat transfer and minimum drag or pressure drop as the oil flows through or past turbulizer 38, as will be described further below.
The assembly of heat exchanger 10 starts by arranging the plates 24, 26 face-to-face or back-to-back as desired, as seen best in FIG. 2, so that the "D"-shaped openings 34 and the respective peripheral edge portions 30 are in registration. If inner tabs 42 are used, these tabs may be first crimped over to form back-to-back plate pairs 44. A turbulizer 38 is then inserted into the hollow space between the central portions 28 of each face-to-face plate pair 12. If peripheral tabs 40 are used, these may then be crimped over the peripheral edge portions 30 of the respective mating plate. Alternatively several of the assembled plate pairs 12 may be formed with turbulizers in them and then stacked together, in which case tabs 42 would not be crimped over or used at all. The particular method or sequence of stacking plates 24, 26 together does not matter, the result is a plurality of stacked plate pairs as illustrated in FIGS. 2 and 7.
The top plate pair 14 is then formed by swaging nipples 22 onto smooth top plate 16 and stacking this on top of one of the plates as shown in FIGS. 1 and 3. Bottom plate pair 18 is then formed using a smooth bottom plate 20 located below the bottom plate 26 as shown in FIGS. 3 and 4.
As seen best in FIG. 6, turbulizer 38 typically is not longitudinally straight, but has a slight transverse camber in it because the metal from which it is formed usually comes in rolled form. This causes the corners 52 and the central portions 54 to overlap or ride into the radius between central portion 28 and peripheral edge 30. However, cladding layers 50 and these radii themselves accommodate this overlap in the brazing process as described next below.
Once the entire heat exchanger is assembled, it is then placed into a brazing furnace using a suitable fixture to maintain the orientation of the assembly, to braze together simultaneously all mating surfaces prior to entering the brazing furnace, the stacked plates appear as shown in FIG. 7, with about a 0.3 m.m. gap between the peripheral edge portions 30 due to the thickness of turbulizer 38 as discussed above. The stacked plates are squeezed together and as the cladding layers 50 melt, peripheral edges 30 come together accommodating any misalignment and dimensional intolerances giving upon cooling a fluid tight assembly.
Having described preferred embodiments of the invention, it will be appreciated that various modifications may be made to the structures described. In certain instances it may be desirable to vary the location of the nipples 22 serving as inlets and outlets for the oil. For example, one nipple 22 could be positioned in the top plate 16 and the other nipple 22 in the bottom plate 20. In the case where the nipples 22 are located at the same end of respective top and bottom plates 16, 20 a central plate with no opening at that end could be positioned in the middle portion of heat exchanger 10.
Heat exchanger 10 can be made from other materials than aluminum, such as stainless steel or brass. In the case of stainless steel, either a brazing cladding layer of copper or thin copper sheets or shims could be used. For the purposes of this disclosure the term "cladding layer" is intended to include any type material to join respective components, such as a coating or metal deposit, a discreet or separate layer of brazing material, solder or even a suitable adhesive. Obviously, any number of plate pairs could be used. Soft soldering may also be used instead of brazing, however in general, this produces a weaker connection and therefore may not meet the strength requirements. The length of the plates can be varied simply by repeating longitudinally the dimple diameter and spacing described above. If both the length and the width of the heat exchanger is to be varied, the diameter and spacing of the dimples may have to be varied slightly in keeping with the parameters discussed above.
From the above, it will be appreciated that the oil cooler of the present invention is a relatively high efficiency heat exchanger which is structurally strong with relatively low pressure drop. | A heat exchanger and method of making same is disclosed. The heat exchanger is particularly useful for cooling automotive engine oil or transmission fluid, the exchanger being located inside the radiator or other part of the engine cooling system. The heat exchanger is made from a plurality of stacked plates formed of cladded metal, the plates being assembled into face-to-face pairs, each pair having a turbulizer located therein. The plates also have outwardly disposed dimples which are in contact when the plates are arranged back-to-back. The turbulizer is thicker than the spacing between the assembled plates prior to brazing the assembly. The dimples maintain good contact between all heat transfer surfaces while the assembly is completed by brazing. | 5 |
RELATED APPLICATIONS
Priority is claimed to International Application No. PCT/US2004/010882 filed on Apr. 7, 2004, and to U.S. Provisional Patent Application No. 60/461,212, Apr. 7, 2003, both of which are hereby incorporated by reference.
GOVERNMENT LICENSE RIGHTS
The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Contract No. N00014-01-1-0928 by the Office of Naval Research.
FIELD OF THE INVENTION
This invention relates to the use of carbonized charcoal as an electrode in a fuel cell, battery or electrolyzer.
BACKGROUND OF THE INVENTION
Carbon batteries played an important role in the history of fuel cell research. In 1855 Becquerel attempted to build a fuel cell that generated electricity by the electrochemical combustion of coal. 1, 2 However, the electrolyte contained a nitrate that attacked the carbon without producing a current. By the end of the 19 th century the increasing demand for electric power in Europe began to consume considerable amounts of coal because the conversion efficiency was very low. 3 Contemplating this problem, in 1894 Ostwald 3 called for development of a fuel cell that would react coal with oxygen to produce electricity more efficiently than thermo-mechanical equipment. Jacques 3 demonstrated a 1.5 kW battery that employed a consumable carbon anode, an iron cathode, and an air-bubbled alkali hydroxide electrolyte to generate 0.9 V at 400-500° C. Operating intermittently, this battery delivered power with an overall efficiency of 32% during a six-month period. The experiment failed because carbonates accumulated in the electrolyte that halted the electrochemistry. 3 In 1937 Baur and Preis 2 tested a fuel cell that used a coke anode and an electrolyte composed of zirconia stabilized with magnesia or yttria at >1000° C. Summarizing the status of carbon fuel cell research as of 1969, Bockris and Srinivasen 2 concluded that carbon fuel cells are impractical because (i) coal is not an electrical conductor, and (ii) graphite is too scarce and expensive to be used as a fuel.
Interest in carbon fuel cells resurfaced during the 1970's, when the Stanford Research Institute (SRI) attempted to develop a coal based fuel cell that employed molten lead at temperatures of 500 to 900° C. 4, 5 Gur and Huggins 6 demonstrated a high temperature (725 to 955° C.) fuel cell that employed stabilized zirconia as a solid electrolyte and a graphite anode.
Other consumable anodes in carbon fuel cells are disclosed by Pesavento 7 and Tao 8 .
Charcoal is mentioned as an anode material, however raw charcoal is not a conductor of electricity. Charcoal is the carbonaceous residue of biomass pyrolysis (thermal decomposition in the absence of oxygen) or starved-air combustion (combustion with insufficient oxygen to permit complete combustion). A good quality charcoal has a fixed-carbon content as measured by ASTM D 1762-84 in excess of about 70%. Fixed-carbon contents above 70% may be realized by heating the charcoal to temperatures of about 400° to 500° C. A representative chemical formula for charcoal is CH 0.60 O 0.13 . 8a When higher carbon content is desired, charcoal is carbonized by heat treatment in the absence of oxygen at temperatures above 500° C. Carbonized charcoals can have carbon contents in excess of 94 wt. %. Some carbonized charcoals are purer forms of carbon than natural graphites.
It is known that carbonized charcoal can possess very high electrical conductivities. In 1810 carbonized-charcoal electrodes were used in an arc lamp, and in 1830 carbonized charcoal was used as an electrode for primary batteries. These electrodes were made from powdered charcoal or coke bonded with sugar syrup or coal tar, pressed and carbonized at high temperatures. 9 Others 10-12 have reported extensive studies of biocarbon electrodes manufactured from charcoal particles bonded together by wood tar and subsequently carbonized. However, the high costs associated with molding, bonding, and carbonizing powdered charcoal makes this approach commercially impractical.
Accordingly, an object of the present invention is to provide an apparatus to enable carbonized-charcoal powder without bonding or molding to be used as an electrode in a fuel cell, battery or electrolyzer.
It is a further object of the present invention to provide carbonized-charcoal powder as the consumable anode of a biocarbon fuel cell.
It is a further object of the present invention to provide carbonized-charcoal powder as an electrode of a hydrogen fuel cell, battery or electrolyzer.
These and other objects and advantages to the present invention will be readily apparent upon reference to the drawing and the following description.
SUMMARY OF THE INVENTION
The present invention provides a method and apparatus for using carbonized charcoal powder as an electrode, wherein the method comprises the steps of (i) loading carbonized-charcoal powder which is carbonized at a temperature above about 900° C. into an apparatus having at least one electrical contact with the powder for providing flow of electricity to or from the carbonized powder wherein the apparatus is adapted for communication of an electrolyte with the carbonized powder; and (ii) applying a compressive force to the carbonized-charcoal powder in the apparatus sufficient to form a compressed bed wherein the bed is characterized by a resistivity of less than about 1 ohm-cm.
The apparatus is used to compress the carbonized charcoal powder and is then useful as an electrode, the apparatus comprising a housing containing a bed of carbonized charcoal powder having a proximal, distal and at least one side surface; a moveable piston in contact with the proximal surface for applying compressive force to compress the bed sufficiently to reduce the resistivity to less than about 1 ohm-cm; at least one electrical contact with the bed to conduct electric current flow into or out of the bed; a device for applying a force to the piston sufficient to cause surface pressure against the bed of at least about 1 MPa; and a porous wall in contact with the bed to conduct liquid or gaseous electrolyte to and from the bed.
The apparatus may also comprise a resistance-measuring device to determine the resistivity of the compressed electrode.
The pressure applied to compress the powder will generally be from about 1 to 10 MPa applied to one surface of the packed powder. In any case, sufficiency of the compressive force may be readily determined by measurement of the electrical resistivity of the compressed electrode. More than one compression application may be required, but typically the desired resistivity is attainable in one compression application. After sufficient resistivity has been attained, the pressure may be released, although it is preferable to keep the pressure applying device in contact with the electrode to ensure the mechanical integrity of the electrode and to provide another electrical conduit to the electrode.
The charcoal will be provided in particulate form, so it must be ground to an average particle size of less than about 10 mm, typically 1 mm or less. The particles will be carbonized by heating to a temperature of at least about 900° C. for several minutes. This carbonized powder will then be loaded into the apparatus serving as both the compressor to form the electrode and as the electrode device itself applicable for use in a fuel cell, battery or electrolyzer.
The source of charcoal may be any biomass that may be pyrolyzed to a fixed-carbon content in excess of about 70%.
After compression the electrode must have a measured resistivity of less than about 1 ohm-cm as measured across opposing faces of the electrode mass where each face serves as the entire electrical contact surface. Typical useful resistivities are about 0.5 ohm-cm or less.
The electrode may be used in known applications utilizing carbon electrodes, such as in a fuel cell, battery or electrolyzer. Therefore the apparatus must have a conduit in electrical communication with the electrode so that it may be connected to an electrical source or appliance, depending upon the particular application. Also, some or all of the walls adjacent to and in contact with the electrode may be made of a porous material to bring a liquid or gaseous electrolyte into contact with the electrode from the exterior of the apparatus. Electrolytes useful in fuel cells, batteries and electrolyzers in conjunction with carbon electrodes are known in the art.
DESCRIPTION OF THE DRAWINGS
The accompanying FIG. 1 is a cross-section elevational view of a preferred electrode according to the invention which also serves as an apparatus for performing the method of the invention.
FIG. 2 is a graph of resistivity vs. compressive pressure of the carbonized charcoals described in Example 1.
FIG. 3 is a graph of resistivity vs. compressive pressure and bed length vs. compressive pressure of carbonized charcoal described in Example 2.
FIG. 4 is a graph of resistivity vs. compressive pressure and bed length vs. compressive pressure of carbonized charcoal described in Example 3.
FIG. 5 a is a graph of resistivity vs. compressive pressure of carbonized charcoal described in Example 4.
FIG. 5 b is a graph of resistivity vs. density of carbonized charcoal described in Example 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
To ensure that the charcoal has a high electrical conductivity, it must be heated (“carbonized”) at a temperature of at least about 900° C. or more for at least a few minutes prior to its use as an electrode. Usually the charcoal carbonization step is accomplished in an oxygen-free environment, but some oxygen (i.e. air) can be present. The charcoal may be ground either before or after carbonization to a fine particle size, preferably so that a substantial portion (greater than about 80% of the particles) are of a size <1 mm. If the charcoal is not ground prior to carbonization, the carbonization time must be sufficient to permit the center of the largest charcoal lumps to reach the desired carbonization temperature and remain at that temperature for a few minutes.
Referring to FIG. 1 , an apparatus 1 according to the invention comprises a vertical, cylindrical tube 16 that retains the carbonized-charcoal bed 11 , a piston 10 within the tube 16 that delivers a compressive force to the carbonized-charcoal bed 11 , and a base 12 within the tube 16 that retains the carbonized-charcoal bed against the compressive force of the piston. The piston 10 , the base 12 , or the tube 16 must be fabricated from an electrically conductive material to enable electricity to flow to or from the carbonized-charcoal bed. If sufficient electrical connection is made with piston 10 and base 12 , tube 16 may be made of a porous insulator, such as alumina, to provide for a liquid or gaseous electrolyte a way to contact the bed 11 . The electrolyte may be provided in the annular space 20 and may communicate with another electrode (not shown) through appropriate interelectrode connection (not shown). An electrically conductive wire 13 leads to a source or sink for electrons (not shown). Force may be applied to the piston by a pneumatic or hydraulic cylinder 6 that can be held conveniently by framework 2 that also supports the tube 16 and the base 12 . Alternatively, instead of base 12 , another piston and cylinder arrangement similar to 4 through 10 may be used. In that case, bed 11 will be compressed between two moveable pistons.
A pressure transducer 4 may be used to monitor and control the force delivered to the piston 10 . When the carbonized-charcoal electrode is used in a battery or fuel cell, the tube 16 may be made of a porous material to permit a liquid or gaseous electrolyte to contact the carbonized-charcoal bed 11 . In some cases it may be desirable to electrically isolate the carbonized-charcoal bed 11 from the support framework 2 and end walls 3 . In this case electrical insulators 14 (e.g. Teflon) may be employed.
Air or hydraulic fluid may be applied through conduit 5 to drive the cylinder 6 . The reach to piston 8 can be adjusted with screw jack 7 . The piston 10 is attached to plunger rod 9 and receiving piston 8 . To provide another electrical connection to the bed 11 , the pistons 8 and 10 and rod 9 are all electrically conductive and electrically connected to wire 18 . Tube 16 and rod 9 are supported and electrically insulated from framework 2 by insulating disk 15 (such as Teflon).
If desired, tube 16 may be fabricated of an electrically conductive material and electrically insulated from either piston 10 or base 12 . Wire 18 or 13 will then be connected to tube 16 instead of piston 8 or base 12 . If tube 16 is electrically conductive, then contact of bed 11 with the electrolyte will be through piston 10 or base 12 , either of which may be fabricated of a porous material.
The resistivity of the bed 11 may be measured by ohm-meter 17 by opening switch 19 b and closing switch 19 a . When the apparatus 1 is used as electrode in a fuel cell, battery or electrolyzer, switch 19 a is open and switch 19 b is closed.
The following examples are provided for the purpose of illustration and are not intended to limit the invention in any way.
EXAMPLE 1
Samples (0.5 g) of 20/40 mesh macadamia nutshell charcoal which had been carbonized for 10 min at temperatures of 650, 750, 850, 950, and 1050° C., were loaded into the apparatus shown in FIG. 1 and the electrical resistivity of the packed-bed, carbonized-charcoal electrode was measured as a function of applied pressure. Referring to FIG. 2 , the electrical resistivity of the carbonized-charcoal packed bed decreased by more than five orders of magnitude as the carbonization temperature increased from 650 to 1050° C. Similarly, in FIG. 2 the electrical resistivity of the packed bed of carbonized-charcoal powder decreased by about a factor of 10 as the applied pressure delivered by the piston 10 (see FIG. 1 ) increased from 0 to about 8 MPa. For comparison, graphite powder was loaded into the apparatus and the resistivity of the graphite powder electrode was measured as a function of increasing pressure. As shown in FIG. 2 an electrode composed of a packed bed of macadamia nutshell charcoal carbonized at 1050° C. manifested an electrical resistivity (0.059 Ω-cm) that was about double that of a graphite powder electrode.
Raw charcoal is typically exposed to temperatures below 600° C. when it is produced from biomass in a kiln or retort. As shown in FIG. 2 charcoal powder manifests a good electrical conductivity (comparable to graphite powder) only after it is carbonized at temperatures of 900° C. or more. Consequently, raw charcoal or charcoal exposed to temperatures below about 900° C. are not suitable for use as electrode material. Likewise, FIG. 2 shows that a carbonized-charcoal, packed-bed electrode manifests a good electrical conductivity (comparable to graphite powder) when the applied pressure to the packed bed exceeds about 1 MPa. Charcoal powder contained in a basket or charcoal powder under pressure of a typical spring will not conduct electricity sufficiently well to be used as an electrode.
EXAMPLE 2
A sample (0.49 g) of 20/40 mesh coconut husk charcoal, which was carbonized at 950° C., was loaded into the apparatus and the electrical resistivity of the packed-bed, coconut husk carbonized-charcoal electrode was measured as a function of applied pressure for two pressurization/depressurization cycles. As shown in FIG. 3 , the electrical resistivity of the coconut husk carbonized-charcoal electrode decreased to a value of 0.18 Ω-cm as the pressure applied to the electrode by the piston increased to about 6 MPa. FIG. 3 also displays the length of the carbonized-charcoal packed bed as a function of pressure. Prior to the first compression the bed was loosely packed and manifested a low electrical conductivity, but following the first compression the compacted bed was relatively dense (0.46 g/cm 3 ) and virtually incompressible.
EXAMPLE 3
A sample (0.5 g) of 20/40 mesh kukui nutshell charcoal, which was carbonized at 950° C., was loaded into the apparatus and the electrical resistivity of the packed-bed, kukui carbonized-charcoal electrode was measured as a function of applied pressure for two pressurization/depressurization cycles. As shown in FIG. 4 , the electrical resistivity of the kukui nutshell carbonized-charcoal electrode decreased to a value of 0.18 Ω-cm as the pressure applied to the electrode by the piston increased to above 6 MPa. FIG. 4 also displays the length of the carbonized-charcoal packed bed as a function of pressure. Prior to the first compression the bed was loosely packed, but following the first compression the compacted bed was quite dense (0.82 g/cm 3 ) and virtually incompressible.
EXAMPLE 4
A sample (0.5 g) of 20/40 mesh Leucaena wood charcoal, which was carbonized at 950° C. was loaded into the apparatus and the electrical resistivity of the packed-bed, Leucaena carbonized-charcoal electrode was measured as a function of applied pressure for two pressurization/depressurization cycles. As shown in FIG. 5 a , the electrical resistivity of the Leucaena carbonized-charcoal electrode decreased to a value of 0.16 Ω-cm as the pressure applied to the electrode by the piston increased to about 6 MPa. For comparison a 0.5 g sample of very fine Leucaena wood charcoal powder, also carbonized at 950° C. was loaded into the apparatus and the electrical resistivity of the Leucaena carbonized-charcoal powder electrode was measured. FIG. 5 a shows that the electrical resistivity of this powder electrode was even lower than the 2/40 mesh carbonized-charcoal with a value of about 0.11 Ω-cm at the highest pressure. FIG. 5 b shows the electrical resistivity of the two electrodes as a function of the carbonized-charcoal density. Following an initial compression the 20/40 mesh carbonized-charcoal bed was virtually incompressible; whereas the fine powder evidenced some compressibility at a much higher density.
Taken together the results of Examples 3 and 4 show that the density (i.e. porosity) of the carbonized-charcoal, packed-bed electrode does not significantly influence its electrical resistivity.
Examples 1-4 show that carbonized charcoal powders derived from a wide variety of different biomass materials are well suited for use as electrode materials according to the invention.
While the invention has been described with reference to particular embodiments thereof, those of skill in the art will be able to make various modifications to the described embodiments without departing from the spirit and scope on the invention. It is intended that the foregoing embodiments are presented only by way of example and that, within the scope of the appended claims and equivalents thereto, the invention may be practiced otherwise than as specifically described.
REFERENCES CITED
(1) Williams, K. R., Ed., An Introduction to Fuel Cells ., Elsevier Publishing Co.: Amsterdam, 1966.
(2) Bockris, J. O. M.; Srinivasan, S. Fuel Cells: Their Electrochemistry .; McGraw-Hill Book Co.: New York, 1969.
(3) Vielstich, W. Fuel Cells .; Wiley-Interscience: London, 1965.
(4) Anbar, M.; McMillen, D. F.; Weaver, R. D.; Jorgensen, P. J. Method and Apparatus for Electrochemical Generation of Power from Carbonaceous Fuels. U.S. Pat. No. 3,970,474, 1976.
(5) Anbar, M. Methods and Apparatus for the Pollution-Free Generation of Electrochemical Energy. U.S. Pat. No. 3,741,809, 1973.
(6) Gur, T. M.; Huggins, R. A. Direct Electrochemical Conversion of Carbon to Electrical Energy in a High Temperature Fuel Cell. J. Electrochem. Soc. 1992, 139, L95.
(7) Pesavento, P. Carbon-Air Fuel Cell. U.S. Pat. No. 6,200,697 B1, 2001.
(8) Tao, T. T. Carbon-Oxygen Fuel Cell. U.S. Patent US 2002/0015877 A1, 2002.
(8a) Antal, M. J.; Gronli, M. G. The Art, Science, and Technology of Charcoal Production. Ind. Eng. Chem. Res. 2003, 42, 1919.
(9) Ford, A. R.; Greenhalgh, E. Industrial Applications of Carbon and Graphite. In Modern Aspects of Graphite Technology ; L. C. F. Blackman, Eds.; Academic Press: London, 1970; p 258.
(10) Coutinho, A. R.; Luerigo, C. A. Preparing and Characterizing Electrode Grade Carbons from Eucalyptus Pyrolysis Products. In Advances in Thermochemical Biomass Conversion ; A. V. Bridgwater, Eds.; Blackie Academic & Professional: London, 1993; p 1230.
(11) Coutinho, A. R.; Luengo, C. A. Mass Balance of Biocarbon Electrodes Obtained by Experimental Bench Production. In Developments in Thermochemical Biomass Conversion ; A. V. Bridgwater and D. G. B. Boocock, Eds.; Blackie Academic & Professional: London, 1997; p 305.
(12) Coutinho, A. R.; Rocha, J. D.; Luengo, C. A. Preparing and characterizing biocarbon electrodes. Fuel Processing Technology 2000, 67, 93. | An apparatus ( 1 ) for use of carbonized charcoal powder as an electrode is provided. Charcoal is provided as a powder, carbonized, and placed in a container ( 16 ) by which compressive pressure is applied to the carbonized-charcoal powder via one or more sides of the container ( 16 ). As a result of the compressive pressure the packed-bed ( 11 ) of carbonized-charcoal powder manifests a resistivity of less than about 1 ohm-cm and is suitable for use as an electrode in a fuel cell, battery or electrolyzer. The apparatus is adapted with electrical contacts ( 8, 9, 10 ) to conduct electric flow to or from the electrode and adapted for communication of an electrolyte with the electrode. | 8 |
FIELD OF THE INVENTION
The present invention relates to a paper-coating composition that enhances optical brightness of coated paper. More specifically, this invention relates to a paper coating composition that has an improved carrier for the optical brightening agents that makes the system more efficient.
BACKGROUND OF THE INVENTION
Prior to the present invention, it was often desirable by coated paper producers to achieve high brightness in the final coated paper product in order to enhance the visual appearance of the paper. Thus, it has become established practice for paper producers to utilize high brightness pigments, such as calcium carbonate and titanium dioxide, and to incorporate fluorescent agents as components of paper coating formulations in order to increase the brightness of paper. These fluorescent agents (more commonly referred to as "optical brightener agents") act by absorbing light radiation waves in the ultraviolet wavelength of the spectrum and re-emitting these light waves in the visible spectrum.
The drawback to the use of these optical brightener agents (OBA) is that their efficiency, when used without other activity-enhancing adjuncts, is relatively poor. OBAs have no inherent affinity for pigments and synthetic lattices, and so in modern paper coatings they are relatively ineffective unless employed with some other component of the coating which has an affinity for the OBA. Thus, it has become an established practice in the paper industry to use OBAs in conjunction with other additives, known as "OBA carriers" that have been empirically established to enhance the OBA effectiveness in paper coatings.
Generally, OBA carriers that are presently being used commercially include polyvinyl alcohol and sodium carboxymethylcellulose. Other materials, noted in the literature that can enhance OBA activity, are: hydroxyethylcellulose, starch, casein, melamine formaldehyde resins, urea formaldehyde resins, and polyglycols. Many of these materials are co-binders commonly used in coatings, and some are cross-linking agents. Hence, these materials are useful tools to enable the paper industry to make efficient use of the OBAs.
It is desired simply that the combined use of OBAs with a selected carrier would provide a higher brightness value of coated paper than that otherwise obtained from the use of prior art OBA and carrier.
U.S. Pat. No. 5, 622,749 discloses the use of PVA or CMC as dispersing agent or auxiliaries with fluorescent whitening agents. Japanese publication JP 90023639 B discloses the use of PVA or its derivatives as a whitening aid with stibene type OBAs in order to prevent discoloration or yellowing by light or heat.
Japanese publication JP 61014979 (86) A discloses the use of water-soluble cellulose derivatives, such as hydroxyethylcellulose, as a carrier for an anionic florescent agent. German publication DE 20 17276-A discloses improving a composition containing a pigment, a binder, an anionic dispersion agent, optionally an OBA, and usual additives dispersed in water by the addition of polyvinylpyrrolidone for enhancing the effect of the OBA.
U.S. Pat. No. 3,892,675 discloses the use of sparingly water-soluble OBAs in coating compositions containing white pigment extenders such as clay and polyvinyl acetate latex as sole binding agent; cellulose ethers, such as CMC, are disclosed as thickeners for the formulation. Publication by J. D. Barnard entitled "The Role of OBAs and Crosslinking Agents" in Paper Technology, 33, No. 9, on pages 24 to 30 (1992) describes the role of OBAs and crosslinking agents in determining the brightness and water resistance of paper. The publication on page 25 lists all of the above noted carriers for OBAs.
SUMMARY OF THE INVENTION
The present invention is an additive system for paper coatings of low viscosity nonionic water-soluble polysaccharide derivatives that are used as carriers for optical brightener fluorescing agents in pigmented paper coatings. Paper coated with these compositions has a significantly brighter surface than a paper coated with the same OBA without the use of these polysaccharide derivatives.
The present invention, also, can be used in a size press application of a starch coating applied to paper. In this instance, no pigment would be present but only the starch, the OBA, and carrier as the primary ingredients.
The present invention is directed to a paper coating composition comprising an optical brightening agent (OBA) and a low viscosity, non-ionic, water-soluble polysaccharide derivative, that exhibits a solution Brookfield viscosity of less than about 1500 centipoise when dissolved in water at a polymer concentration of 5% by weight at ambient temperature (25° C.) wherein the paper coating provides improved optical brightness as compared to the same formulation without said non-ionic, water soluble, polysaccharide derivative.
The present invention, also, relates to a method of brightening paper comprising coating the paper with the above-mentioned composition.
The present invention also comprehends a paper coated with the above-mentioned composition.
The present invention, also, is directed to a method of making the above mentioned paper coating composition comprising combining an optical brightening agent and a water-soluble, non-ionic, polysaccharide derivative that exhibits a solution Brookfield viscosity of less than about or equal to 1500 centipoise when dissolved in water at a polymer concentration of 5% by weight at 25° C.
DETAILED DESCRIPTION OF THE INVENTION
It has been surprisingly found that low molecular weight forms of nonionic, water-soluble, polysaccharide derivatives, when used in conjunction with certain other additives, known as fluorescing agents, as components of a paper coating formulation, significantly increase the brightness of coated paper or offer other advantages as compared to prior art additive systems.
In accordance with the present invention, preferred polysaccharide derivatives are nonionic, water-soluble cellulose ethers. Examples of the cellulose ethers are hydroxyethylcellulose (HEC), hydroxypropylcellulose (HPC), methylcellulose (MC), methylhydroxyethylcellulose (MHEC), methylhydroxypropylcellulose (MHPC), ethylhydroxyethylcellulose (EHEC), hydroxyethylmethylcellulose (HEMC), hydroxyethylguar, hydroxypropylguar, hydroxyethylstarch, and hydroxypropylstarch. The polysaccharide derivatives of this invention also can be hydrophobically modified with C4-28 alkyl or aryl, or arylalkyl groups. The preferred cellulose ether is a low molecular weight HEC.
The present invention is, in essence, the concerted use of two ingredients in a pigmented paper coating: 1) a low viscosity water-soluble nonionic water-soluble polysaccharide derivative, and 2) a fluorescing agent. These two ingredients when employed as additives in a standard pigmented paper coating formulation, that also contains pigment and binder, impart higher brightness to coated paper than either the OBA or the water-soluble polymer when used alone would impart to such paper.
In a typical paper coating, the coating formulation is prepared by dispersing pigments, such as kaolin clay and calcium carbonate into water, then adding in binder, such as polystyrene butadiene copolymer and/or an aqueous solution of cooked starch. Other paper coating ingredients, such as rheological modifiers, biocides, lubricants, antifoaming compounds, crosslinkers, and pH adjusting additives may also be present in small amounts in the coating.
Examples of pigments that can be used in coating formulations are kaolin, calcium carbonate (chalk), China clay, amorphous silica, silicates, barium sulfate, satin white, aluminum trihydrate, talcum, titanium dioxide and mixtures thereof. Examples of binders are starch, casein, soy protein, polyvinylacetate, styrene butadiene latex, acrylate latex, vinylacrylic latex, and mixtures thereof. Other ingredients that may be present in the paper coating are, for example, dispersants such as polyacrylates, lubricants such as stearic acid salts, preservatives, antifoam agents that can be either oil based, such as dispersed silica in hydrocarbon oil, or water-based such as hexalene glycol, pH adjusting agents such as sodium hydroxide, rheology modifiers such as sodium alginates, carboxymethylcellulose, starch, protein, high viscosity hydroxyethylcellulose, and alkali-soluble lattices.
According to the present invention, a quantity of water-soluble polysaccharide derivative is added to the coating formulation at a dosage amount having an upper limit of about 3.0 parts active ratio based upon the pigment component. The preferred upper limit is about 2.0 parts and more preferably about 1.0 part. The lower limit of the polysaccharide derivative is about 0.1 part, preferably about 0.2 part, and more preferably about 0.3 part.
The solution viscosity range of the low viscosity, water-soluble polysaccharide derivatives of the present invention, when dissolved in a ratio of 5 parts by weight of polymer in 95 parts of water exhibits less than 1500 cps viscosity as measured by a standard Brookfield instrument at ambient temperature. Preferably, the viscosity should be less than 1000 cps and more preferably less than 500 cps.
The use of such water-soluble polymers is advantageous as compared to prior art use of higher viscosity, water-soluble polysaccharides in that such low viscosity additives can be incorporated at relatively high dosages into paper coatings without causing excess thickening of the coating that would limit its ease of metering onto a paper web.
To improve ease of incorporation into paper coating formulations polysaccharide derivatives can be prepared in concentrated aqueous suspension form (see U.S. Pat. Nos. 4,883,536 and 5,028,263). For example, concentrated suspensions of polysaccharide derivatives can be prepared by dissolving specific inorganic dispersants and stabilizers in water by a proprietary process and then adding 25% by weight of the polysaccharide derivative to this solution. Thus, based on this patented technology the commercial products (i.e., ADMIRAL® 3089FS Fluidized Polymer Suspension, ADMIRAL® 2089FS Fluidized Polymer Suspension and ADMIRAL® 1089FS Fluidized Polymer Suspension) have been developed by Hercules Incorporated. ADMIRAL® 3089FS Fluidized Polymer Suspension comprises an HEC polymer that produces an aqueous viscosity of greater than about 2000 cps when added to water in a ratio such that the HEC concentration is 5% by weight. By comparison both ADMIRAL® 2089FS Fluidized Polymer Suspension and ADMIRAL® 1089FS Fluidized Polymer Suspension comprise low viscosity HEC water-soluble polymers that each produces an aqueous viscosity of less than about 500 cps when added to water in a ratio such that the HEC concentration is 5%.
In addition to the normal amount of the polysaccharide derivative carrier present in the coating, the OBA ingredient should be present in an amount having an upper limit of about 4.0 parts active based on pigment. The preferred upper limit of the OBA is about 2.0 parts, more preferably about 1.0 part. The lower limit of the amount of the OBA is about 0.1 part, preferably 0.2 part, and more preferably about 0.3 part.
In accordance with the present invention, the paper coating is applied by various means to the surface of paper or paperboard to achieve a given coat weight and then dried to form the final paper product. Many conventional methods are known in the prior art for applying the coating to the surface of the paper. Three of the most common types of coaters are blade, rod, and air knife. Blade coaters use a metal or ceramic blade at a certain angle and pressure to meter a several micrometer thick coating onto a sheet. The blade coater is the most common type of coater.
The fluorescing agents or OBAs found to be useful in combination with the nonionic water-soluble cellulose derivatives of this invention include 4,4'-bis(triazinyl) amino-stilbene-2,2'-disulfonic acid (tetra sulfonated) and 4,4'-bis 2-sulfostyryl-biphenyl (distyrylbiphenyl). This first type of OBA (tetra sulfonated) is traditionally used in the paper industry within paper coatings. Distyrylbiphenyl (DSBP) is a new class of OBAs recently offered for paper coatings. Other OBA additives such as disulfonated, and hexasulfonated substituted fluorescing agents would also be expected to be operative with this invention.
In accordance with the present invention, the paper coated with an OBA and the low viscosity, non-ionic, water-soluble polysaccharide derivative of this invention exhibits both whiteness and brightness values of greater than 70, preferably greater than 80 and more preferably greater than 90 units as measured on an X-Rite® 968 Spectrophotometer for whiteness and a Diano ® 5-4 Brightness Tester and Colorimeter for brightness. Also, this paper exhibits an improved supercalender gloss as compared to prior art OBA carriers.
This invention has advantages over the prior art use of polyvinyl alcohol in that the polysaccharide derivative of this invention does not require extensive cooking and preparation as does polyvinyl alcohol (PVA). Thus, this invention represents a significant enhancement in ease of use over prior art. Also, the present invention produces less adverse effect on glossing ability of the coated paper as compared to the PVA prior art OBA carrier.
The following examples are merely set forth for illustrative purposes, but it is to be understood that other modifications of the present invention within the skill of artisans in the industry can be made without departing from the spirit and scope of the invention.
EXAMPLES
Standard Process
Two different coating formulation master batches were prepared. As a first step, the pigment (either all kaolin clay or a 50:50 blend of kaolin/calcium carbonate) was made into an aqueous slurry at 75% total solids. Dispex ® N 40 product (sodium polyacrylate) was used at 0.15 active parts based on pigment as a dispersion aid. After 1 hour of high shear mixing, 10 parts of styrene butadiene latex were added to the pigment slip using low speed agitation. Diluent water as then added to reach approximately 63% solids and pH was adjusted with 30% ammonium hydroxide to 8.5. The final solids reduction to 61.5% was performed in each separate aliquot used for the individual sample coatings.
These formulations differed in the selection of pigment types with one formulation using 100% kaolin clay as the coating pigment, while the other formulation using a mixture of 50% kaolin clay and 50% calcium carbonate (See Table 1 and 2, infra). A standard binder of styrene butadiene latex was used in all tests at 10 parts based on 100 parts of pigment.
Each paper coating type, whether it was based upon 100% kaolin clay pigment or a mixture of kaolin with calcium carbonate, was divided into several aliquots and to each of the aliquots was added various water-soluble polymer additives and OBAs. In the paper-coating tests that used polyvinyl alcohol as the OBA carrier, it was necessary to cook the PVA at 200° F. for at least 40 minutes in order to hydrate completely. In the tests that used HEC as the OBA carrier, it was not necessary to cook the HEC in order to hydrate. This latter polymer was instead added directly to the coating either in solution or in Fluidized Polymer Suspension form and allowed to hydrate with stirring in-situ which required only about 15 minutes. Two different OBAs were used in the study: 4,4'-bis(triazinyl)amino-stilbene-2,2'-disulfonic acid (TETRA), and 4,4'-bis2-sulfostyryl-biphenyl (DSBP).
For runnability purposes, either sodium carboxymethylcellulose or sodium alginate was added to each paper coating to produce a Brookfield viscosity of approximately 1500 cps as measured with an RVT viscometer #4 spindle at 100 RPM. The prepared formulations were then coated onto rolls of commercial 62# paper using a laboratory Dow® coater (Serial #079, Type 89B-SS) at various speeds to give a range of coat weights. The finished-coated paper was recovered and paper samples were selected from each of the tests that corresponded to the equivalent coating weight pick-up of approximately 5 pounds per 3,000 square feet of paper.
These coated paper samples were then measured for whiteness using an X-Rite® 968 Spectrophotometer and for brightness using a Diano® S-4 Brightness Tester and Colorimeter. The standard methods for these instruments were used for each of these measurements.
Example 1
(100% Kaolin Clay Coatings)
In this Example, 100% kaolin clay was used as the paper coating pigment ingredient. The coating formulation tested is shown in Table 1. Descriptions of each water-soluble polymer OBA carrier used in the separate coatings tests are set forth infra in Table 2.
The final paper properties observed for paper that was treated with these various formulations are shown in Tables 4 and 5.
It was found in these tests that ADMIRAL® 1089 FS Fluidized Polymer Suspension, i.e. low viscosity nonionic hydroxyethylcellulose, at 0.5 part active polymer based on pigment with 1.0 part distyrylbiphenyl OBA, produced the highest brightness and second highest whiteness of all OBA carriers tested at this addition level. These results are shown in Table 3. An experimental ultra low viscosity solution of hydroxyethylcellulose gave the highest whiteness results. However, by comparison ADMIRAL® 3089 FS Fluidized Polymer Suspension (the higher viscosity analogue of ADMIRAL® 1089 FS Fluidized Polymer Suspension) produced lower brightness and whiteness results. This result essentially established the unexpected finding of the present invention; low viscosity hydroxyethylcellulose is more effective as an OBA carrier for coated paper than HEC that exhibits an aqueous viscosity of greater than 1500 cps at 5% aqueous concentration.
Distyrylbiphenyl OBA gave an average of 0.6 points of brightness gain or 4.4 points of whiteness versus the 4,4'-bis(triazinyl)amino-stilbene-2,2'-disulfonic acid (TETRA) (See Table 4).
TABLE 1______________________________________100% Kaolin Clay RecipeHuber ® Hydrasperse (#2 kaolin clay) 100 partsDow ® 620 SBR (styrene butadiene latex) 10 partsDispex N-40 (dispersion aid) 0.1 partsWater addition to 61% solidsOBA Carrier 0.0, 0.50, or 1 partsOBAs:4,4'-bis(2-sulfostyryl) biphenyl) (DSBP) 0, or 1 parts4,4'-bis(substituted triazinyl) maino-stilbene-2,2'-disulfonic acid(TETRA)CMC 7LCT or 9M31CF (for viscosity control) Added to thicken coating to Target of 1500 cps______________________________________
TABLE 2______________________________________OBA CarriersName Description______________________________________ADMIRAL ® 1089FS Fluidized 25% active Fluidized PolymersPolymer Suspension Suspension of Natrosol ® 250LR Hydroxyethylcellulose, 5% active polymer aqueous viscosity <500 cps.ADMIRAL ® 2089FS Fluidized 25% active Fluidized PolymersPolymer Suspension Suspension of Natrosol ® 250JR Hydroxyethylcellulose, 5% active polymer aqueous viscosity < 500 cps.ADMIRAL ® 3089FS Fluidized 25% active Fluidized PolymersPolymer Suspension Suspension of Natrosol ® 250GR Hyrdroxyethylcellulose, 5% active polymer aqueous viscosity ≧2000 cps.Experimental Ultra Peroxide-degraded solution oflow viscosity HEC hydroxyethylcellulose, 10% active polymer solution viscosity <100 cps (See U.S Pat. No. 5,480,984)Klucel ® Hydroxypropyl- Low molecular weightcellulose Type 99-L hydroxypropylcellulose 5% active polymer aqueous viscosity <500 cpsCulminal ® MHPC 25 Low molecular weightMethylhydroxy- methylhydroxypropylcellulosepropylcellulose 5% active polymer aqueous viscosity <500 cpsCulminal MC25S Low molecular weightMethylcellulose methylcellulose 5% active polymer aqueous viscosity <500 cpsAirvol 203S Polyvinyl Alcohol 88% hydrolyzed polyvinyl alcohol(Air Products)______________________________________
TABLE 3______________________________________Various OBA Carriers at 0.5 Parts Dosage with1 Part DSBP OBA added in 100% Kaolin Clay Coatings Coated Coated Paper PaperOBA Carrier @ 0.5 Parts Brightness Whiteness______________________________________ADMIRAL ® 1089FS 87.0 87.7Fluidized Polymer SuspensionAirvol ® 203S Polyvinyl Alcohol 86.3 82.6ADMIRAL ® 3089FS 86.4 82.1Fluidized Polymer SuspensionExperimental Ultra Low viscosity HEC 85.9 88.3Klucel ® Hydroxypropylcellulose Type 99-L 86.0 87.3Culminal ® MHPC 25 85.7 87.1MethylhydroxypropylcellulloseCulminal ® MC25S Methylcellulose 85.5 86.4______________________________________
TABLE 4______________________________________Various OBA Carriers, at 0.5 Parts Dosage, with1 Part of Two OBA Types in 100% Kaolin Clay Coatings Coated Coated Paper Paper Brightness Whiteness______________________________________OBA Type: TETRA DSBP TETRA DSBPOBA CarrierADMIRAL ® 1089FS Fluidized 85.7 87.0 81.5 87.7Polymer SuspensionAirvol ® 203S Polyvinyl Alcohol 85.3 86.3 81.5 82.6ADMIRAL ® 3089FS Fluidized 85.5 86.4 81.3 82.1Polymer SuspensionExperimental Ultra Low 85.7 85.9 81.5 88.3viscosity HECKlucel ® Hydroxypropyl- 85.7 86.0 81.9 87.3cellulose Type 99-LCulminal ® MHPC 25 85.2 85.7 81.1 87.1MethylhydroxypropylcelluloseCulminal ® MC25S 85.4 85.5 81.4 86.4Methylcellulose______________________________________
Example 2
(50% Kaolin Clay:50% Calcium Carbonate Coatings)
In this series of tests, 50% kaolin clay along with 50% calcium carbonate were used as the coating pigment ingredients. The paper coating formulations tested are shown in Table 5. The descriptions of each water-soluble polymer/OBA carrier are shown above in Table 2. The final paper properties observed for paper that was treated with these various formulations are shown in Tables 6 through 9. All of these coatings were thickened to a target coating viscosity range by adding various quantities of Kelgin® LV sodium alginate.
Since coated paper is normally glossed with a supercalender, brightness and gloss results were taken on supercalendered samples. Supercalender conditions were 2 passes, 100° F., 16.5 feet per minute, and 1,600 pounds per linear inch.
It was found that the coated papers that included DSBP, an OBA, and a low viscosity hydroxyethylcellulose, at 0.5 to 1.0 part based on pigment in the paper coating formulation, exhibited the highest brightness of all OBA carriers evaluated (See Table 6 and 8). By comparison the paper coating that incorporated ADMIRAL® 3089 FS Fluidized Polymer Suspension (the higher viscosity analogue of ADMIRAL® 1089 FS Fluidized Polymer Suspension) or PVA exhibited lower brightness results.
The selection of the OBA type was also found to influence the coated paper brightness. Distyrylbiphenyl OBA gave an average of 1.1 points of brightness gain at the 0.5 part dosage of OBA carrier when compared to 4,4'-bis(triazinyl)amino-stilbene-2,2'-disulfonic acid (TETRA). At the 1.0 part dosage of OBA carrier, distyrylbiphenyl OBA gave 1.5 points of brightness gain compared to 4,4'bis(triazinyl)amino-stilbene-2,2'-disulfonic acid (TETRA) (See Table 7).
Gloss measurements of the various coated paper samples showed that the paper coating that incorporated 0.5 parts of low viscosity hydroxyethylcellulose exhibited the highest gloss values independent of OBA type (See Table 9).
TABLE 5______________________________________50% Kaolin Clay: 50% Calcium Carbonate Paper CoatingHuber Hydrasperse (#2 kaolin clay) 50 partsHuber Hydracarb 90 (calcium carbonate) 50 partsDow 620 SBR (styrene butadiene latex) 10 partsDispex N-40 (dispersion aid) 0.1 partsWater addition to 61% solidsOBA Carrier 0.0, 0.25, 0.50, 0.75, or 1 partsOBAs: 0, or 1 parts4,4'-bis(2-sulfostyryl) biphenyl) (DSBP)4,4'-bis(substituted triazinyl) maino-stilbene-2,2'-disulfonic acid (TETRA)Kelgin LV Sodium Alginate (for viscosity control) Added to thicken coating to Target of 1500 cps______________________________________
TABLE 6______________________________________Hydroxyethylcellulose and Polyvinyl Alcoholat Two Dosages with 50% Kaolin Clay: 50% CalciumCarbonate Paper Coating Recipe, 1 Part DSBP OBA Added Supercalendered Supercalendered Brightness of Brightness of Coated Paper Coated Paper with 0.5 Parts with 1.0 Part of OBA Carrier of OBA Carrier______________________________________OBA CarrierADMIRAL 1089 FS 87.7 87.9Fluidized Polymer SuspensionAirvol 203S Polyvinyl Alcohol 86.8 87.7ADMIRAL 3089 FS 87.1 87.6Fluidized Polymer Suspension______________________________________
TABLE 7______________________________________Hydroxyethylcellulose and Polyvinyl Alcoholwith Two OBA Types, 50% Kaolin Clay: 50% CalciumCarbonate Paper Coating Recipe Supercalendered SupercalenderedOBA Carrier Brightness Brightness______________________________________ 0.5 Parts of OBA Carrier 1.0 Part of OBA CarrierType of OBA: TETRA, 1 DSBP, 1 TETRA, 1 DSBP, 1 Part Part Part PartADMIRAL 1089FS 86.3 87.7 86.2 87.9Fluidized PolymerSuspensionAirvol 203S 85.7 86.8 86.3 87.7Polyvinyl AlcoholADMIRAL 3089 FS 86.4 87.1 86.3 87.6Fluidized PolymerSuspension______________________________________
TABLE 8______________________________________Various Low Viscosity HydroxyethylcelluloseTypes, 50% Kaolin Clay: 50% Calcium Carbonate PaperCoating Recipe With 1 Part DSBP OBA Unsupercalendered SupercalenderedOBA Carrier Brightness Brightness______________________________________ 0.5 Parts of OBA Carrier 0.5 Parts of OBA CarrierControl (No 87.1 85.7OBA Carrier)ADMIRAL 1089 FS 89.6 88.6Fluidized PolymerSuspensionADMIRAL 2089 FS 89.6 88.6Fluidized PolymerSuspensionAirvol 203S 89.6 88.1Polyvinyl Alcohol______________________________________
TABLE 9______________________________________Gloss Results for Supercalendared PaperTreated with 100% Kaolin Clay Coatings andVarious OBA Carriers and OBA Types @ 1 Part TETRA OBA DSBP OBA Coated Paper Coated PaperOBA Carrier Gloss Results Gloss Results______________________________________0.50 Parts ADMIRAL 1089 56.1 58.5FS FluidizedPolymer Suspension0.50 Parts Airvol 203S 55.3 55.9Polyvinyl Alcohol0.50 Parts ADMIRAL 54.6 57.23089 FS FluidizedPolymer Suspension______________________________________ | A paper coating composition has therein an optical brightening agent (OBA) and a water-soluble non-ionic polysaccharide derivative, exhibiting a solution viscosity in water of less than 1500 cps when dissolved at 5% polymer concentration, wherein the paper coating provides improved optical brightness as compared to the same formulation without said non-ionic, polysaccharide derivative. A paper coated with this composition has an optical brightness value of greater than 70. | 3 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
The invention described herein may be manufactured and used by or for the government of the United States of America for governmental purposes without the payment of any royalties thereon or therefore.
BACKGROUND OF THE INVENTION
Generally, an arena test consists of the detonation of a warhead to propel fragments that then become embedded in the arena walls, accompanied by a gathering of the data associated with those embedded fragments.
The rough estimation of warhead fragmentation performance has been accomplished through the application of the basic theories of Taylor, Mott, Gurney, and Shapiro. More specifically, in the past, a legacy warhead evaluation process (“legacy process”) has been used to roughly predict warhead performance. The Taylor, Mott, Gurney, and Shapiro theories were applied using warhead physical characteristics and dimensions. The first applied theory was that of Taylor, which is used to determine a Taylor angle. A Taylor angle describes the fragmentation ejection angle for a limiting deflection of a plane detonation wave using a warhead model that approximates a long right cylinder model. The next applied theory was that of Mott. Mott uses a weight scaling equation to determine an average fragment weight. The next theory was that of Gurney. The Gurney equation predicts a fragment velocity. The next applied theory was that of Shapiro. Shapiro was used to determine a Shapiro angle, which provides a generalized fragment ejection angle based on a non-plane detonation wave for a general cylinder model. The theories are then applied to each of the discrete warhead model case segments as defined for a warhead model. The warhead model is defined geometrically and then divided into theoretical slices, where each slice is a discrete warhead model case segment.
For each discrete warhead model case segment the “legacy” theories applied above produced an average fragment weight, an average fragment velocity, an average fragment direction, and a fragment count. Thus, three numbers characterized the fragmentation for each warhead model case segment. The results for each discrete warhead model case segment were then averaged, and an average performance model for a warhead was produced. The “legacy” process does not model the true nature of the warhead detonation because the true nature of a warhead fragmentation distribution is continuous in weight, velocity, and direction, and not discrete. Further, the “legacy” process, and other prior processes, did not include means for modeling end fragments. The “legacy” process also did not include a Monte-Carlo model round-to-round variability because the legacy process did not include the effects of continuous distributions nor did it include randomness.
SUMMARY
One embodiment of the invention is directed to a warhead performance modeling computer program product in a computer readable medium having computer readable program code recorded thereon, wherein the computer readable program code include sets of instructions.
One exemplary embodiment of the invention includes loading computer instructions for causing a computer to read and store a parameters file and a warhead file; the warhead file provides information indicating the number of warhead model case segments in a warhead. The exemplary embodiment also includes warhead model setup instruction(s) for causing a computer to set up a warhead model. The warhead model includes an average fragment weight per warhead model case segment, an average fragment velocity per warhead model case segment, and an average fragment ejection angle per warhead model case segment. The embodiment also includes a plurality of sets of computer instructions for executing a segment loop; a maximum number of iterations of the segment loop is equal to the number of warhead model case segments in the warhead (indicated by information provided in the warhead file). The exemplary embodiment includes warhead model retrieval and fragment count instructions programmed to operate within the segment loop for causing a computer to retrieve/recall data included in the warhead model. The exemplary embodiment also includes distribution setup computer instructions programmed to operate within the segment loop for causing a computer to set up a fragment weight distribution, a fragment velocity distribution, and a fragment ejection angle distribution. The exemplary embodiment also includes a plurality of sets of computer instructions for executing a fragment loop programmed to operate within the segment loop; a maximum number of iterations of the fragment loop is equal to the number of fragments in the warhead model case segment. The exemplary embodiment also includes setup distributions retrieval instructions programmed to operate within the fragment loop for causing the computer to retrieve the setup distributions. The exemplary embodiment also includes a working value generating instruction(s) programmed to operate within the fragment loop and controlling a plurality of parameterized random number generators, the working value generating instruction(s) including instructions for causing a computer to:
use each of the retrieved setup distributions to parameterize one of the random number generators based at least in part by one of the retrieved setup distributions such that each of the random number generators is parameterized at least in part by one of the retrieved setup distributions, initialize at least one of the parameterized random number generators to produce an output, generate a fragment performance profile using the outputs, the fragment performance profile including a working value fragment weight, a working value fragment velocity, and a fragment working value ejection angle, and store the fragment performance profile in a fragment performance data structure.
The exemplary embodiment also includes a correlation instruction(s) for causing a computer to execute a correlation loop programmed to operate within the fragment loop. The correlation loop iterates through the setup distribution(s) retrieval instructions and the working value generating instruction(s) for generating a fragment performance profile using the outputs until a correlation between a plurality of the working values has been established.
The exemplary embodiment also includes end fragment generating instruction(s) programmed to execute within the fragment loop for causing a computer to generate end fragments. The end fragment instructions use as input a polar working value fragment ejection angle, . The end fragment generating instruction(s) having computer readable code for causing a computer to generate a first random number D and a second random number X, and comparing X to D. The end fragment generating instruction(s) include instructions for causing the computer to exit the end fragment generating instruction(s) when X is less than or equal to D. The end fragment generating instruction(s) include instructions for causing the computer to do the following when X is greater than D:
1) generate Theta1 (θ 1 ), a random value greater than or equal to zero (0) and less than or equal to one hundred and eighty (180), compare Theta1 (θ 1 ) to , and:
when Theta1 (θ 1 ) is greater than or equal to ,
generate a random angle Theta2a (θ 2a ), update and store the value of to be equal to Theta2a (θ 2a );
when Theta1 (θ 1 ) is less than ,
generate a random angle Theta2b (θ 2b ), update and store the value of to be equal to Theta2b (θ 2b );
2) generate a random number Y, compare Y to the Random Velocity Cutoff, and:
when Y is greater than the Random Velocity Cutoff, generate a multiplier m 1a such that the multiplier is equal to the sin( ), multiply the working value fragment velocity, (W frag velocity ), for the fragment as determined in the working value generating computer instructions by m 1a and store the product as the working value fragment velocity, (W frag velocity ), in the fragment performance profile in the fragment performance data structure; when Y is not greater than the Random Velocity Cutoff, generate a random number Z, generate a multiplier such that the multiplier (m 1b ) is equal to Z*sin( ), multiply the working value fragment velocity, (W frag velocity ), for the fragment as determined in the working value generating computer instructions by m 1b , store the product as the working value fragment velocity, (W frag velocity ) in the fragment performance profile in the fragment performance data structure.
When multiple Monte Carlo iterations are to be performed, the exemplary embodiment also includes instructions for causing the computer to determine whether a Monte Carlo iteration remains to be performed. When another Monte Carlo iteration remains to be performed, the exemplary embodiment includes instructions for causing the computer to save the data from the current Monte Carlo iteration in computer memory such that the computer can distinguish data from previous Monte Carlo iterations, re-seed the random number generators, and analyze the warhead again. The exemplary embodiment also includes a user-defined format generating instruction(s) for causing a computer to process the field performance data structure. The processing results in a statistically based warhead performance model wherein the statistically based warhead performance model can be used to predict a warhead performance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-C are a high level flow diagram according to an embodiment of the invention.
FIGS. 2A and 2B depict a more detailed flow diagram of blocks 110 and 115 in FIG. 1 .
FIG. 3 is a data flow diagram of the segment loop according to an embodiment of the invention.
FIG. 4 is an expansion of one step in the data flow diagram of FIG. 3 , depicting the fragment loop according to an embodiment of the invention.
FIG. 5A depicts a partially segmented warhead with angular references relating to a fragment ejection angle.
FIG. 5B illustrates one embodiment of a cylindrically cross-sectional view of a warhead with angular references to the roll angle.
FIG. 6A illustrates the geometry used to determine the fragment ejection angle.
FIG. 6B is a flow diagram illustrating how to convert a fragment ejection angle to a field polar angle according to an embodiment of the invention.
FIGS. 7A and 7B comprise a flow diagram illustrating the end fragment process according to an embodiment of the invention.
FIGS. 8A-8F each show a partial visual depiction of the output of one embodiment of the invention, presented as fragmentation performance polar plots from runs for a 2.75 inch rocket warhead.
FIGS. 9A-B provide a flowchart of a Monte Carlo loop according to an embodiment of the invention.
FIG. 10 is a screen shot of one embodiment of the invention; the screen shot includes most of FIGS. 8A-F .
DETAILED DESCRIPTION OF THE EMBODIMENTS
Although embodiments of the invention are described in considerable detail, including references to certain versions thereof, other versions are possible. Examples of other versions include performing the steps in an alternate sequence, reconstructing the loops to populate data structures in a different order, or hosting the program on a different platform. Therefore, the spirit and scope of the appended claims should not be limited to the description of versions contained herein.
Embodiments of the invention may take the form of a computer program product on a computer-usable storage medium having computer-usable/readable program code embodied in the medium. Any suitable computer readable medium may be utilized including either computer readable storage mediums, such as, for example, hard disks, CD-ROMs, optical storage devices or magnetic storage devices, or a transmission media, such as, for example, those supporting the internet or an intranet.
Computer-usable/readable program code for carrying out operations of embodiments of the invention may be written in an object oriented programming language such as, for example, Python, Visual Basic, or C++. However, computer-usable/readable program code for carrying out operations of embodiments of the invention may also be written in conventional procedural programming languages, such as, for example, the “C” programming language. The computer-usable/readable program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer. In the latter scenario, the remote computer may be connected to the user's computer through a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider or any other method known in the art).
Embodiments of the invention are described in part below with reference to flow chart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each block of the flow chart illustrations and/or block diagrams, and combinations of blocks in the flow chart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flow chart and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function/act specified in the flow chart and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts specified in the flow chart and/or block diagram block or blocks.
A general overview of one embodiment of the invention is depicted in FIGS. 1A , 1 B, and 1 C. The user/operator may choose to process the warhead more than once, i.e., perform multiple runs (or Monte Carlo iterations), in which case, the user will input, using an interface, the number of Monte Carlo iterations to be performed. The default number of Monte Carlo iterations is one (1).
A computer program product in accordance with embodiments of the invention includes instructions (or a set of instructions) for causing a computer to accept as input (read and store; load) what are referred to in this specification, including the claims, as a warhead file (step 110 ) and a parameters file (step 110 ) (referred to in this specification, including the claims, as “loading instructions”). The parameters file specifies the correlation parameters, (C w , C v ), field filters, the model (or Monte Carlo) seed, and rules (for example whether a distribution will be a beta distribution, normal distribution, or some other type of distribution) for continuous model distributions (set up using a set of instructions described infra., as represented in block 140 in FIG. 1 ) comprising a fragment ejection angle distribution, a fragment velocity distribution, and a fragment weight distribution. The model (or Monte Carlo) seed is the seed for a given Monte Carlo iteration that is used to initiate, or seed, all random number generators in a Monte Carlo iteration. A user can select/input a model seed value using an interface. When no model (or Monte Carlo iteration) seed is selected/input, the model seed is generated from the computer's system clock. The warhead file includes a set of user defined warhead parameters. The user defined warhead parameters contained within the warhead file include the warhead description data, including the explosive type and characteristics, including the explosive detonation velocity (v d ), warhead case data (including warhead case dimension, case thickness, and weight), and warhead model case segments description; the parameters contained within the warhead file define the polar zones, and include fragmentation and field data, including the fragment weight parameter, and the warhead field configuration. The warhead model case segment lengths included in the warhead model case segments description in the warhead data file are ideally selected such that each warhead model case segment, 515 in FIG. 5A , is as long as possible, consistent with matching the actual warhead case profile 510 . In one embodiment, an ideal fragment weight distribution results were obtained by using a warhead model that is cylindrically symmetric about the z-axis (z-axis illustrated in FIG. 5A ).
An analysis using a plurality of warhead model case segments (a segmented warhead model) raises the question of how long to make each warhead model case segment, 515 in FIG. 5A . At this time, no guidance on warhead model case segment length has been found in the literature and the choice of warhead model case segment length is rather arbitrary. Large warhead model case segment lengths provide more justification for the non-interacting warhead case segment assumptions, at the expense of losing fragmentation fine structure along the warhead or device length. Very small warhead model case segment lengths probably violate the non-interaction assumption. Small warhead model case segment lengths appeared to violate the long-cylinder assumptions made by the pioneers in warhead modeling until it was realized that the long-cylinder assumption is just another way of saying that the detonation wave is planar as it propagates along the warhead to be modeled. To a first approximation, a detonation wave tends to become planar as it propagates from one end to the opposite end of the model cylinder. Thus, the warhead segments that are far from the end of explosive initiation will experience a plane wave no matter what length the warhead model segments are.
A computer program product in accordance with embodiments of the invention has instructions (or a set of instructions) for causing a computer to set up a warhead model (referred to in this specification, including the claims, as “warhead model setup instructions”) (generally shown as block 115 in FIG. 1A ; generally represented by block 115 in FIG. 2A and more particularly represented by blocks 250 , 260 , 270 , 280 , 290 , 300 , and 310 in FIG. 28 ).
The warhead model setup instructions used to set up a warhead model include instructions for causing a computer to compute the metal physical characteristics for each warhead model case segment (block 250 ) by any known method using information contained in the warhead file (block 110 in FIGS. 1A and 2A ). The metal physical characteristics include, for each warhead model case segment, 515 in FIG. 5A , a metal volume, an interior volume (the volume the warhead model case segment encloses), and inside and outside surface normal angles. The warhead model setup instructions include instructions for causing a computer to compute the explosive physical characteristics for each warhead model case segment 515 (block 260 in FIG. 2B ) by any known method using information contained in the warhead file (block 110 in FIGS. 1 and 2A ). The explosive physical characteristics include, for each warhead model case segment, 515 in FIG. 5A , a volume and weight for the explosive in the warhead model case segment 515 , and a charge to metal ratio for the warhead model case segment 515 . The warhead model setup instructions include instructions for causing a computer to compute, for each warhead model case segment 515 , warhead model case segment parameters associated with determining a warhead model case segment fragment ejection polar angle (average fragment ejection angle for the warhead model case segment) (φ s , FIG. 6A ) (block 270 in FIG. 28 ) for the warhead model case segment using information from the warhead file (block 110 in FIGS. 1 and 2A ). The warhead model case segment parameters associated with determining a warhead model case segment fragment ejection polar angle (average fragment ejection angle for the warhead model case segment) (φ s , FIG. 6A ) for the warhead model case segment, 515 in FIG. 5A , include an inside case surface normal vector for the warhead model case segment ({circumflex over (η)}, FIG. 6A ), which is perpendicular to the inside case surface cross line ( 808 , FIG. 6A ), (which is a straight line that intersects the intersections 810 and 812 of the warhead model case segment boundaries ( 802 , 804 , FIG. 6A ) and the inside case surface ( 816 , FIG. 6 A)), and its corresponding inside case surface normal angle, (φ 1 , FIG. 6A). 806 marks the longitudinal (along the x-axis in FIG. 6A and the z-axis in FIG. 5A ) center of the warhead. 814 in FIG. 6A points to the illustrated portion of an exemplary warhead case. The warhead model setup instructions include instructions for causing a computer to save in computer memory the computed warhead model case segment parameters associated with determining a fragment ejection polar angle (average fragment ejection angle for the warhead model case segment) (φ s , FIG. 6A ) (block 270 in FIG. 2B ) for the warhead model case segment, 515 in FIG. 5A . The warhead model setup instructions include instructions for causing a computer to compute, for each warhead model case segment 515 , warhead model case segment fragment velocity parameters (block 280 ) using information from the warhead file (block 110 in FIGS. 1 and 2A ); the warhead model case segment fragment velocity parameters for the warhead model case segment, 515 in FIG. 5A , include a Gurney fragment velocity for the warhead model case segment v ƒ using Gurney's equation for cored cylinders (Equation 1) and a Taylor angle using Taylor's theory (Equation 2). The Taylor angle is measured from the inside case surface normal vector ({circumflex over (η)}, FIG. 6A ) and, for many devices/warheads, is rarely much larger than about 8.5 degrees. The Taylor angle is a function of the detonation velocity and the Gurney fragment velocity. The Taylor angle is the limiting value of the Shapiro angle (Equation 3), meaning that the absolute value of the Shapiro angle cannot be larger than the absolute value of the Taylor angle.
v
f
=
G
C
(
M
C
+
a
+
3
6
(
a
+
1
)
)
-
1
2
(
1
)
where:
v ƒ =Gurney average fragment velocity
G C =Gurney Constant for the explosive in the warhead
M=case weight
C=explosive weight
a
=
r
c
r
i
=
core
radius
case
inside
radius
r c =core radius=radius of a cylindrical hollow of a warhead model case segment, usually for placement of a fuze
r i =case inside radius of a warhead model case segment
sin
(
γ
i
)
=
(
v
f
2
v
d
)
(
2
)
where:
γ t =Taylor angle
v f =Gurney fragment velocity
v d =explosive detonation velocity
The warhead model setup instructions include instructions for causing a computer to save in computer memory the computed warhead model case segment velocity parameters for each warhead model case segment for use with fragment velocity calculations—including setting up the fragment velocity distribution, which occurs using a set of instructions described infra., as represented in block 140 in FIG. 1 . The warhead model setup instructions include instructions for causing a computer to compute a warhead model case segment fragment ejection polar angle (average fragment ejection angle for the warhead model case segment) (φ s , FIG. 6A ) for the warhead model case segment (for use with ejection angle distributions) for all warhead model case segments using Shapiro's theory (Equation 3), limited where applicable by Taylor's theory, and Equation 4 (block 290 in FIG. 2B ).
tan
(
γ
s
)
=
(
v
f
2
v
d
)
cos
(
ϕ
2
)
(
3
)
where:
γ s =Shapiro deflection angle
φ 2 =angle of the warhead model case segment cross section center measured from the case nose.
Note that γ s is taken to be positive when the angle of the warhead model case segment fragment velocity vector, ( ν 0 , FIG. 6A ), with respect to the z-axis, measured from the nose, is greater than the angle of the normal unit vector, ({circumflex over (ƒ)}, FIG. 6A ), with respect to the z-axis, measured from the nose; γ s is taken to be negative when the angle of the warhead model case segment fragment velocity vector, ( v 0 , FIG. 6A ), with respect to the z-axis, measured from the nose, is less than the angle of the normal unit vector, ({circumflex over (η)}, FIG. 6A ), with respect to the z-axis, measured from the nose. Knowing the Shapiro deflection angle, γ s , the warhead model case segment fragment ejection angle (average fragment ejection angle for the warhead model case segment) (φ s , FIG. 6A ) is computed using Equation 4.
φ s =φ 1 +γ s (4)
where, φ 1 =inside case surface normal angle γ s =Shapiro deflection angle as computed using Equation 3
The warhead model setup instructions include instructions for causing a computer to save in computer memory the Shapiro deflection angle, γ s , and the warhead model case segment fragment ejection angle (average fragment ejection angle for the warhead model case segment) (φ s , FIG. 6 A)—for use with setting up the fragment ejection angle distributions (fragment ejection angle distributions are set up using a set of instructions described infra., as represented in block 140 in FIG. 1 ). The warhead model setup instructions include instructions for causing a computer to compute a warhead model case segment fragment weight ( m finaliteration ) for each warhead model case segment, ( m finaliteration ), by applying an iterative correction (Equation 6) (iterated until successive values of m n+1 differ by <0.1 grain) to the uncorrected warhead model case segment fragment weight, m 0 , (Equation 5) (block 300 ), using information in the warhead file (block 110 in FIGS. 1 and 2A ).
m
_
0
=
2
B
2
t
5
3
d
i
2
3
(
1
+
t
d
i
)
2
(
5
)
where:
m 0 =uncorrected warhead model case segment fragment weight
B=Mott factor
t=warhead model case segment thickness
d i =case inside diameter of a warhead model case segment=2r i
m
_
n
+
1
=
m
_
0
2
[
2
-
m
_
n
W
seg
(
ln
2
(
W
seg
m
_
n
)
+
2
ln
(
W
seg
m
_
n
)
+
2
)
]
(
6
)
where:
m 0 =uncorrected warhead model case segment fragment weight,
m n =n th iteration of corrected average fragment weight; m n = m 0 during a first Monte Carlo iteration,
m m+1 =(n+1) th iteration of corrected average fragment weight,
W seg =warhead model case segment weight
For each warhead model case segment, the final iteration of the correction to the Mott result (using Equation 6), m finaliteration , is taken to be the warhead model case segment fragment weight (average fragment weight for the warhead model case segment). For each warhead model case segment, the warhead model setup instructions include instructions for causing a computer to save in computer memory the uncorrected warhead model case segment fragment weight, m 0 , and warhead model case segment fragment weight, m finaliteration , for use with fragment weight calculations, including setting up the fragment weight modified-Mott distribution, which occurs using a set of instructions described infra., as represented in block 140 in FIG. 1 .
FIG. 3 is a flowchart of a “segment loop” according to one embodiment of the invention; a “segment loop” is also marked in FIG. 1 with arrow line 102 . For each Monte Carlo iteration, each warhead model case segment, 515 in FIG. 5A , is processed individually in a segment loop until each warhead model case segment 515 in the warhead 510 is processed. Within the segment loop, for each warhead model case segment 515 , embodiments of the invention include instructions for causing a computer to recall the warhead model (found in blocks 250 , 260 , 270 , 280 , 290 , 300 , 310 in FIG. 2B ) and compute a “fragment count” (blocks 130 in FIGS. 1 and 3 ) using the computed warhead model case segment fragment weight m finaliteration and warhead model case segment weight W seg (referred to in this specification, including the claims, as “warhead model retrieval and fragment count instructions”). The invention includes instructions that, for each warhead model case segment, use the warhead model case segment fragment ejection angle (average fragment ejection angle for the warhead model case segment), (φ S , FIG. 6A ), warhead model case segment fragment weight, m finaliteration and Gurney fragment velocity, v f , to set up a distribution for each characteristic (fragment weight, fragment velocity, and fragment ejection angle). For each characteristic, a random number generator is used to generate a random number from a random variable distributed according to one of the setup distributions. Embodiments of the invention include instructions for causing a computer to cause an electronic uniform random number generator to generate a random number based on a distribution generated to approximate the statistical distribution of each characteristic. Described infra is one implementation of a method for causing an electronic random number generator to generate a random number based on a distribution generated to approximate the statistical distribution of each characteristic; however, other approaches for causing an electronic random number generator to generate a random number based on a distribution, including but not limited to the inverse transform method, designed to approximate the statistical distribution of each characteristic should be known to a person having skill in the art.
Within the segment loop, for each warhead model case segment 515 in FIG. 5A , embodiments of the invention include instructions for causing a computer to set up distributions for each characteristic (fragment weight, fragment velocity, and fragment ejection angle) for the warhead model case segment 515 (blocks 140 in FIGS. 1 and 3 ) using a number of constants (calculated in steps 250 , 260 , 270 , 280 , 290 , 300 , 310 or contained within the parameters file (block 110 in FIG. 2 )) as input setup parameters (referred to in this specification, including the claims, as “distribution setup instructions”). Fragment size, that is, dimensions, is estimated from the fragment weight for different materials using empirical rules derived from field data. Fragment location in the warhead model case segment is determined using independent, uniform random number generators that specify each fragment's position along the warhead model case segment length and in roll angle about the warhead model case segment axis. The distribution setup instructions include instructions for causing a computer to store in computer memory the setup fragment weight distribution, fragment velocity distribution, and fragment ejection angle distribution for the current warhead model case segment 515 .
The distribution setup instructions include instructions for causing a computer to setup/create a fragment weight distribution for the current warhead model case segment 515 using the modified Mott distribution function in Equation 7. The range of the fragment weight distribution is from 0 to m max .
N
(
m
)
=
N
0
(
ⅇ
2
m
m
_
finaliteration
-
-
ⅇ
2
m
max
m
_
finaliteration
-
)
(
7
)
where:
N 0 =total number of fragments from warhead model case segment
m=single fragment mass
N(m)=number of fragments of mass m from warhead model case segment
m finaliteration =warhead model case segment fragment weight
m
max
=
1
2
(
ln
(
N
0
)
)
2
=
maximum
fragment
mass
for
warhead
model
case
segment
The desired distribution for modeling fragment velocities and fragment ejection angles is the beta distribution. The beta distribution is flexible and also has the desirable characteristic of having a finite domain. In this regard it is realized that most other commonly used analytic distributions have either an infinite domain, such as, for example, the normal distribution, or a semi-infinite domain, such as, for example, the exponential. The beta distribution has a domain of [0,1], i.e., defined on the interval [0,1], (the [0,1] domain is referred to as “unscaled”), that can be scaled as needed. The beta distribution domain can be made to correspond to the finite range of physical processes such as, for example, velocity and ejection angle.
The density function for the standard beta distribution can be written as:
b
(
x
,
r
,
s
)
=
x
(
r
-
1
)
(
1
-
x
)
(
s
-
1
)
Beta
(
r
,
s
)
(
8
)
where:
Beta(r,s) is the beta function and appears as a normalization constant to ensure that the total probability integrates to unity,
r is a distribution shape factor,
s is a distribution shape factor,
x is a random variable.
The integral of the density function of Equation 9 over some range of x corresponds to the Microsoft Excel function: BETADIST(x,Alpha,Beta). The desired approach, described in this specification, sets up fragment velocity, and fragment ejection angle, distributions that are scaled, non-normalized versions of a standard beta distribution (Equation 8). The distribution shape factors of the fragment velocity distribution (r v and s v ) and the fragment ejection angle distribution (r e and s e ) selected for use in a method in accordance with the invention are greater than 1.0, and thus the density functions describing the fragment velocity distribution and fragment ejection angle distribution are humped density functions. Setting up these distributions is a process of controlling the position and shape of the hump.
The fragment velocity distribution for each warhead model case segment 515 is set up by scaling a non-normalized version of the standard beta distribution in Equation 9 from 0 to √{square root over (2)}G C , (G C is provided in the warhead file, block 110 in FIGS. 1 and 2A ), producing a non-normalized scaled beta distribution that is parameterized by the velocity shape factors (r v and s v ), as described by the density function in Equation 10. The non-normalized, scaled (from 0 to √{square root over (2)}G C ) beta distribution described by the density function in Equation 9 is referred to in this specification including the claims as the “fragment velocity distribution”. It is noted that Equation 10 does not present a density function that describes a standard beta distribution because a standard beta distribution is defined on the interval [0,1] and is normalized.
v ( x v ,r v ,s v )= x v (r v −1) (1− x v ) (s v −1) (9)
where: v=fragment velocity probability density function x v =fragment velocity K v =r v +s v =fragment velocity shape parameter, which serves as a constraint r v =λ v (K v −2)+1=fragment velocity distribution shape factor s v =(K v −r v )=fragment velocity distribution shape factor
λ v = v f 2 G C = distribution normalized peak position
distribution normalized peak position
ν ƒ =Gurney fragment velocity G C =Gurney constant
In one embodiment, the finite domain of the fragment velocity distribution is selected to be (0 to √{square root over (2)}G C ); in other words, the fragment velocity distribution is defined on the interval [0, √{square root over (2)}G C ].
The significance of the Gurney fragment velocity, ν ƒ , can vary as follows: 1) ν ƒ can be considered the most probable velocity; or 2) ν ƒ can be considered the average velocity. The interpretation of ν ƒ being the most probable velocity is a desired default interpretation.
In one embodiment where ν ƒ is selected to be the most probable velocity, the distribution setup instructions include instructions for causing a computer to set up the fragment velocity distribution for the current warhead model case segment using Equation 9, with the fragment velocity distribution shape factors (r v and s v ) computed as follows:
r v =λ v ( K v −2)+1; and (10)
s v =K v −r v (11)
A primary effect of changing
C M
is to move the distribution peak, i.e. the most probable velocity, around. For a given value of G C , very high or very low values of
C M
tend to have sharper peaks for a given value of K v than mid-range values of
C M .
This is the effect of “squeezing” the peaks against the limits of the domain. Generally, the total kinetic energy of all of the fragments increases as K v becomes larger because the resulting narrow velocity distribution produces more higher velocity fragments.
In one embodiment where v f is selected to be the average velocity, the distribution setup instructions include instructions for causing a computer to set up the fragment velocity distribution for the current warhead model case segment using Equation 9, with the fragment velocity distribution shape factors (r v and s v ) computed using Equations 12 and 13.
s v =K v (1−λ v ), and (12)
r v =K v −s v (13)
In another embodiment, sometimes referred to as a “flexi-beta method”, where v f is selected to be the average velocity, the distribution setup instructions include instructions for causing a computer to set up the fragment velocity distribution for the current warhead model case segment 515 using Equation 10, with the fragment velocity distribution shape factors (r v and s v ) computed as follows:
1) compute a temporary r v using Equation 13; 2) compare the temporary R v with
λ
v
1
-
λ
v
,
a) when the temporary r v as calculated in Equation 13
< λ v 1 - λ v ,
then
set the shape factor r v to,
r v = λ v 1 - λ v , and ( 14 )
and (14) set s v =1;
b) when the temporary r v as calculated in Equation 13
≥ λ v 1 - λ v ,
then
set the distribution shape factor r v to r v =K v (as set in parameters file) (block 110 in FIG. 2A ), and set
s
v
=
1
-
λ
v
λ
v
.
(
15
)
The distribution setup instructions include instructions for causing a computer to set up the fragment ejection angle distributions for each warhead model case segment 515 by scaling a non-normalized version of the beta distribution in Equation 8 from −2(γ t ) to 2(γ t ) for a total range of four times the Taylor angle (γ t ) (computed in the warhead model setup instructions using Equation 2), producing a non-normalized scaled beta distribution that is parameterized by the fragment ejection angle shape factors (r e , s e ) as described by the density function in Equation 16. The non-normalized scaled, (from −2(γ t ) to 2(γ t )), beta distribution described by the density function in Equation 16 is referred to in this specification including the claims as the “fragment ejection angle distribution”. The domain of the fragment ejection angle distribution (−2(γ t ) to 2(γ t )) therefore covers angles less than and greater than 0 degrees measured from the inside surface case normal vector ({circumflex over (η)} in FIG. 6A ). It is noted that Equation 16 does not present a density function that describes a standard beta distribution because a standard beta distribution is defined on the interval [0,1] and is normalized.
a ( x e ,r e ,s e )= x e (r e −1) (1− x e ) (s e −1 ) (16)
where: a=fragment ejection angle probability density function x e =warhead case segment fragment ejection angle=φ s K e =r e +s e =fragment ejection angle distribution shape parameter, which serves as a constraint r e =λ e (K e −2)+1=fragment ejection angle distribution shape factor S e =(K e −r e )=fragment ejection angle distribution shape factor
λ
e
=
γ
t
-
γ
s
2
γ
t
=
fragment
ejection
angle
distribution
normalized
peak
position
γ t =Taylor's angle
γ s =Shapiro's angle
φ s as calculated using Equation 4 is taken to be the warhead case segment fragment ejection angle and corresponds to the peak of the density function that describes the fragment ejection angle distribution. The fragment ejection angle distribution shape parameter, K e , contained in the parameters file (block 110 in FIG. 2A ) is used to parameterize the fragment ejection angle distribution. The fragment ejection angle distribution gets peakier as K e gets larger. The effect of adjusting the fragment ejection angle shape parameter, K e , is subtler than adjusting the fragment velocity shape parameter, K v , and no simple rules for determining behavior apply. This is especially true since the ejection angles are correlated with the fragment velocities via the Velocity Correlation Parameter in a complex way. Experience so-far indicates that an Ejection Angle Shape Parameter value of 10 may be used as a starting point.
Within the segment loop is a “fragment loop”. FIG. 4 is a flowchart of a “fragment loop” according to one embodiment of the invention; a “fragment loop” according to an embodiment of the invention is also marked in FIG. 1 with arrow line 102 . The term “fragment loop” describes a loop comprised of instructions (or sets of instructions) that evaluate each fragment in the current warhead model case segment 515 one at a time. The fragment loop (marked in FIG. 1 with arrow line 101 , and shown particularly in FIG. 4 ) iterates until all of the fragments within a warhead model case segment have been evaluated, i.e., the fragment loop iterates, for each warhead model case segment, the warhead model case segment's 515 “fragment count” number of times.
With reference to the fragment loop of FIG. 4 , and the fragment loop indicated by line 101 in FIG. 1 , for each fragment in the current warhead model case segment 515 , embodiments of the invention include instructions for causing a computer to retrieve/recall from computer memory the setup distributions stored in computer memory and the basic fragment performance data (found in blocks 250 , 260 , 270 , 280 , 290 , 300 , and 310 in FIG. 2B ) (block 161 in FIG. 4 ) (referred to in this specification, including the claims as “setup distributions retrieval instructions”).
For each fragment in the current warhead model case segment 515 in FIG. 5A , and for each setup distribution, a random number generator generates a value that represents (or is used to compute a value that represents) the characteristic the distribution is used to determine (for example, the fragment weight distribution is used to determine a fragment's weight, the fragment velocity distribution is used to determine a fragment's velocity, and the fragment ejection angle distribution is used to determine a fragment's ejection angle) based on the setup distribution. Embodiments of the invention include instructions for causing a computer to generate a weight, a velocity, and an ejection angle for each fragment in the current warhead model case segment 515 (referred to in this specification, including the claims as “working value generating instructions”), by: 1) initializing (causing to run) a random number generator paramaterized on a version of the setup weight distribution (block 409 in FIG. 4 ) to generate a value that represents (or is used to compute) the fragment's assigned weight (block 410 ); 2) initializing a random number generator parameterized on a version of the setup velocity distribution (block 411 ) to generate a value that represents (or is used to compute) the fragment's assigned velocity (block 415 ); and 3) initializing a random number generator parameterized on a version of the setup ejection angle distribution (block 413 ) to generate a value that represents (or is used to determine) the fragment's assigned ejection angle ( 420 ).
In one embodiment, the setup distributions stored in computer memory and the basic fragment performance data are used to map, using any known method, a uniformly distributed random number r having range 0≦r≦1 into a variable t having range 0≦t≦1 where occurrences of t are distributed based on the density function ƒ(β), where ƒ(β) represents the density function describing the setup fragment weight distribution, fragment velocity distribution, and fragment ejection angle distribution.
For each setup distribution, given the discrete density function z=ƒ(β), for β 0 ≦β i ≦β n having breakpoints B 0 , B 1 , B 2 . . . B p in the β direction,
where
β 0 is the minimum of the domain (for fragment velocity, 0; for fragment weight, 0; for fragment ejection angle, −2(γ t )),
β n is the maximum of the domain (for fragment velocity, √{square root over (2)}G C ; for fragment weight, m max ; for fragment ejection angle, 2(γ t )),
The working value generating instructions include instructions for causing a computer to transform the density function z into a normalized and unscaled, i.e., scaled from [0,1], density function (z′=ƒ(t)), and implement a random number generator having the characteristics of the normalized and unscaled density function (z′). The mapping variable, t, is a normalized unscaled, i.e., scaled from [0,1], version of β. Note that the β i are taken to be equally spaced at distance Δβ.
The function t=h(r) is a monotonically increasing mapping function made up of line segments having a slope given by the method described below that maps the variable r to the variable t. If r is chosen using a uniform random number generator then the mapping variable t will be a random number distributed according to the normalized and unscaled, i.e., scaled from [0,1], density function. That is, the uniform density function will be mapped into the normalized and unscaled, i.e., domain range [0,1], density function, z′=ƒ(t).
In all cases, the value of a variable β over the interval β k-1 <β≦β k is β k-1 as a left-hand limit.
In one embodiment, for each setup distribution, the working value generating instructions include instructions for causing a computer to scale the setup distribution by translating the interval/range of β i to [0,1]. This is done by mapping β→t, (β 0 ≦β i ≦β n →t 0 ≦t i ≦t n ), using the scaling relation:
t i = ( β i - β 0 ) ( β n - β 0 ) where 0 ≤ i ≤ n , t 0 = 0.0 , t n = 1.0 ( 17 ) where 0≦i≦n, t 0 =0.0, t n =1.0 (17)
The scaled breakpoints in the t domain are:
T k = ( B k - B 0 ) ( B p - B 0 ) where 0 ≤ k ≤ p , T 0 = 0.0 , T p = 1.0 ( 18 ) where 0≦k≦p, t 0 =0.0, T p =1.0 (18)
For each density function describing a desired distribution (the fragment weight distribution, fragment velocity distribution, and fragment ejection angle distribution), the area contained by the density function is:
A = ∑ i = 1 n z i ( β i - β i - 1 ) = ∑ k = 1 p Z k ( B k - B k - 1 ) , with z 0 = z 1 and Z 0 = Z 1 ( 19 ) with z 0 =z 1 and Z 0 =Z 1 (19)
where: z i is the value of z over the interval z i-1 <z≦z i , Z k is the value of z over the interval Z k-1 <z≦Z k consistant with the definition of the breakpoints Z k as the left-hand limit described above.
From Equation 19, the working value generating instructions include instructions for causing a computer to compute the area contained by the unscaled density function:
A ~ = ∑ i = 1 n z i ( t i - t i - 1 ) = ∑ k = 1 p Z k ( T k - T k - 1 ) , with z 0 = z 1 and Z 0 = Z 1 ( 20 ) with z 0 =z 1 and Z 0 =Z 1 (20)
where t 0 =T 0 =0 and t n =T p =1 and T k is the value of t over the interval T k-1 <t≦T k as a left-hand limit.
The working value generating instructions include instructions for causing a computer to normalize the density function z=ƒ(β) to produce a distribution that is described by a density function having an under curve area of 1. The instructions cause the computer to normalize the density function using Equation 21.
A
_
=
1
=
A
~
A
~
=
1
A
~
∑
i
=
1
n
z
i
(
t
i
-
t
i
-
1
)
=
∑
i
=
1
n
(
z
i
A
~
)
(
t
i
-
t
i
-
1
)
=
∑
i
=
1
n
z
i
~
(
t
i
-
t
i
-
1
)
(
21
)
letting {tilde over (z)} 0 ={tilde over (z)} 1
or in terms of the breakpoints
A _ = ∑ k = 1 p ( Z k A ~ ) ( T k - T k - 1 ) = ∑ k = 1 p Z ~ k ( T k - T k - 1 ) , where ( 22 ) where (22)
Z
~
k
=
Z
k
A
~
,
1≦k≦p,
Z 0 =Z 1 ,
{tilde over (Z)} 0 ={tilde over (Z)} 1 , and
{tilde over (z)} i is the scaled z value.
The resulting function in t and {tilde over (z)} i (Equation 21) is (a discrete version of) the density function used to parameterize the random number generator. The scaled variable {tilde over (z)} i is also the slope of the mapping line segments in t|r space, so r 0 =t 0 =0.0 and r n =t n =1.0 must map all of the space. The values of the breakpoints in r space are (R 0 , R 1 , . . . , R p ). The working value generating instructions cause the computer to determine the breakpoints in r space using Equation 24.
R k ={tilde over (Z)} k ( T k −T k-1 )+ R k-1 where R 0 =0.0 and 1≦ k≦p (23)
Each line segment of h(r) spans adjacent breakpoints in the collection (R 0 , R 1 , . . . , R p )|(T 0 , T 1 , . . . , T p ) each having the form:
t=m k r+b k-1 over the range R k-1 <r≦R k which maps into T k-1 <t≦T k for 1≦ k≦p (24)
So:
m k = 1 Z ~ k = A ~ Z k = ( T k - T k - 1 ) ( R k - R k - 1 ) , ( 25 ) and: b k =( T k −m k R k )=( T k-1 −m k R k-1 ) (26)
where b 1 =0
and:
t = m k ( r - R k ) + T k = ( A ~ Z k ) ( r - R k ) + T k for R k - 1 < r ≤ R k ( 27 ) for R k-1 <r≦R k (27)
and:
t=m k ( r−R k-1 )+ T k-1 (28)
In other words, for each density function describing a desired distribution (the fragment weight distribution, fragment velocity distribution, and fragment ejection angle distribution), given the vectors Z and B corresponding to the input density function ƒ(β), the working value generating instructions include instructions for causing a computer to:
1. Set T 0 =0.0, R 0 =0.0, Z 0 =Z 1 ;
2. Compute the vector T from the vector B using Equation 18;
3. Compute the scalar à from the vectors Z and T using Equation 19;
4. Compute the vector {tilde over (Z)} from the vector Z and the scalar à using Equation 22;
5. Set {tilde over (Z)} 0 ={tilde over (Z)} 1 ;
6. Compute the vector R from the vectors {tilde over (Z)}, and T using Equation 23;
7. Compute the vector m from the vector {tilde over (Z)} using Equation 24;
8. Set m 0 =m 1 ;
9. Set up an index array to hash into the distribution array corresponding to the vector R;
10. Construct the transform t out =ψ[r,ƒ(β)] that maps a random number r having range 0≦r≦1 into a variable t (the distribution of t being described by a density function with an under area curve of 1 and a range of 0≦t≦1), where occurrences of t are distributed based on the density function z=ƒ(β).
The instructions cause the computer to implement the transformation by mapping the domain defined by r into a range divided into p segments. Each segment in the range corresponds to a linear mapping function defined by Equation 27 or Equation 28. Given the value r from the uniformly distributed random number generator, in one embodiment, the working value generating instructions include instructions for causing a computer to implement steps 9 and 10 on pages 45 and 46 of this specification using the following procedure:
a) Setup an array that indexes into the distribution array R(k) by intervals of 0.1:
int indexArray[11]; indexArray[0]=0; for(d=0.1, k=−1, i=1; i<11; i++) { while(k<p&&R[k]<=d) k++; indexArray[i]=k; d+=0.1; }
b) Hash to the index into the distribution array:
for(k=indexArray[(int)(10.0*r)];r>R[k];k++);
c) Compute the transformed value of random variable r.
tout=m[k]*(r−R[k])+T[k];.
This works for the unevenly spaced intervals defined by the R k so given k, then:
t out =m k ( r−R k )+ T k (29)
for R k-1 <r≦R k , and 1≦k≦p.
The working value generating instructions include instructions for causing a computer to transform the output variable, t out , back into the original domain (for weight: 0 to m max ; for velocity: 0 to √{square root over (2)}G C ; for ejection angle: −2(γ t ) to 2(γ t )), producing a “working value”, W frag , for each characteristic of the current fragment (the working value fragment weight, W frag weight , working value fragment velocity, W frag velocity , and working value fragment ejection angle, W frag ejection ) using:
W frag =(β n −β 0 ) t out +β 0 (30)
Within the fragment loop, for each fragment, embodiments of the invention include “correlation instructions” used to execute a “correlation loop” programmed to operate within the fragment loop; the “correlation instructions” include instructions for causing a computer to analyze at least two of the working values (W frag ) and to loop/iterate through the correlation loop ( 409 , 411 , 413 , 410 , 415 , and 420 in FIG. 4 ) until it is established that a pre-determined correlation (step 105 ) between at least two of the working values (W frag ) exists, i.e., until exit conditions are met. A fragment's working values W frag that have been determined to be correlated comprise the “fragment performance profile”. Note that a fragment's “fragment performance profile” may be updated/changed if end fragments are generated.
In one embodiment, a pre-determined correlation between at least two of the working values (W frag ) can be:
1) a correlation between fragment velocity and fragment ejection angle, or 2) a correlation between fragment weight and fragment ejection angle.
In this embodiment, the pre-determined correlations between fragment velocity and fragment ejection angle, and fragment weight and fragment ejection angle are based on the following principles:
1) fragments traveling at a higher velocity correlate with higher fragment ejection angles; 2) lighter fragments tend to be ejected away from the calculated ejection angle.
In this embodiment, a pre-determined correlation between at least two of the working values (W frag ) exists (exit conditions are met) when the ejection angle random deviate is greater than the velocity random deviate taken to the C v power and/or the ejection angle is less than the fragment weight random deviate taken to the C w power. In this embodiment, the correlation instructions include instructions for causing a computer to (note that 1 and 2 immediately following can be performed in either order):
1) retrieve/recall the ejection angle random deviate and the velocity random deviate, compute the velocity random deviate taken to the C v power, compare the ejection angle random deviate to the velocity random deviate taken to the C v power; and
a) when the ejection angle random deviate is greater than the velocity random deviate taken to the C v power (thereby meeting exit conditions), exit the correlation loop into step 430 ; b) when the ejection angle random deviate is not greater than the velocity random deviate taken to the C v power, and
i) when it has been determined that the ejection angle random deviate is not less than the fragment weight random deviate taken to the C w power, instruct the computer to perform an additional iteration of the fragment loop; ii) when it has not been determined that the ejection angle random deviate is not less than the fragment weight random deviate taken to the C w power, instruct the computer to proceed to 2;
2) retrieve/recall the ejection angle random deviate and the velocity random deviate, compute the fragment weight random deviate taken to the C w power, compare the ejection angle random deviate and the fragment weight random deviate taken to the C w power, and
a) when the ejection angle random deviate is less than the fragment weight random deviate taken to the C w power (thereby meeting exit conditions), exit the correlation loop into step 430 ; b) when the ejection angle random deviate is not less than the fragment weight random deviate taken to the C w power, and
i) when it has been determined that the ejection angle random deviate is not greater than the fragment velocity random deviate taken to the C v power, instruct the computer to perform an additional iteration of the fragment loop; ii) when it has not been determined that the ejection angle random deviate is not greater than the fragment weight random deviate taken to the C v power, instruct the computer to proceed to 1.
The variables C v and C w are the correlation parameters and are read from the parameters file. When the current iteration's working values (W frag ) meet the correlation parameters, exit conditions are met, and the loop is exited into step 430 .
Embodiments of the invention include “roll angle generating instructions” for causing a computer to generate a roll angle ( FIG. 5B ) for the current fragment as a uniformly distributed random value between 0 and 360 degrees (step 430 ).
With reference to FIGS. 6A and 68 (and generally represented by block 166 in FIG. 4 ), working value fragment ejection angle converting instructions include instructions for causing a computer to convert the working value fragment ejection angle (W frag ejection ) to external coordinates 166 in FIG. 6B and FIG. 1B , thereby generating what is referred to in this specification including the claims as a “polar working value fragment ejection angle” ( ) ( 813 in FIG. 6A ). The instructions cause a computer to generate by causing a computer to:
1) compute the case polar angle, α, from the known fragment case coordinates using Equation 32 (step 605 in FIG. 6B ):
tan(α)= y c /x c , where (31)
x c =fragment case ejection x position relative to the field origin, and y c =fragment case ejection y position relative to the field origin;
2) compute the internal case polar radius from the fragment case coordinates using Equation 32 (step 610 ):
r =( x c 2 +y c 2 ) 1/2 , where (32)
x c =fragment case ejection x position relative to the field origin, and y c =fragment case ejection y position relative to the field origin;
3) compute the distance from the fragment case coordinates to the fragment field coordinates using Equation 33 (step 615 ):
s =( R 2 −r 2 *sin 2 (α− W frag ejection )) 1/2 −r ×cos(α− W frag ejection ) (33)
where R is the fragment field radius, r is the internal case polar radius and was calculated in step 610 , α is the fragment case polar angle and was calculated in step 605 , and W frag ejection is the working value fragment ejection angle, calculated as in step 420 in FIG. 4 .
4) compute the fragment field coordinates relative to the field origin using Equations 34 and 35 (step 620 in FIG. 6B ):
x f =x c −s *cos( W frag ejection ), where (34)
x c =fragment case ejection x position relative to the field origin, s is the distance from the fragment case coordinates to the fragment field coordinates and was computed in step 615 , and W frag ejection is the working value fragment ejection angle, calculated as in step 420 in FIG. 4
y f =y c −s *sin( W frag ejection ), where (35)
y c =fragment case ejection y position relative to the field origin, s is the distance from the fragment case coordinates to the fragment field coordinates and was computed in step 615 in FIG. 6B , and W frag ejection is the working value fragment ejection angle, calculated as in step 420 in FIG. 4 ;
5) compute the polar working value fragment ejection angle, , using Equation 36 (step 625 in FIG. 6B ):
tan( )= y f /x f , where (36)
y f and x f are the fragment field coordinates relative to the field origin and were computed in step 620 .
One embodiment of the invention includes end fragment generating instructions for causing a computer to generate end fragments (end fragments are fragments outside the main beamspray, where the beamspray is defined to be fragments generated between polar angles 45 to 135 degrees from the nose, directed toward the nose and the tail of the warhead) (referred to in this specification, including the claims, as “end fragment generating instructions”). In embodiments where end fragments are to be generated, the “fragment loop” includes step 167 in FIGS. 1B and 4 . Beginning with step 167 , FIGS. 7A and 7B illustrate a flow chart of end fragment generating instructions according to an embodiment of the invention. In one embodiment where end fragments are to be generated, the end fragment generating instructions are activated from the command line and use user controlled parameters as well as default parameters. The end fragment generating instructions, in effect, cause a computer to randomly move selected fragments from the beamspray region to outside the main beamspray region.
For example, in one embodiment, end fragment generating instructions include instructions for accepting as input a user assigned/selected value of a variable/parameter referred to as an “End Fragment Factor”, which is a random number between 0 and 1.0. One possible default value that can be assigned to the End Fragment Factor is 0.90. In this embodiment, the end fragment generating instructions also include instructions for accepting as input a user assigned/selected variable/parameter referred to as a “Random Velocity Cutoff”, which is a random number between 0 and 1.0. In this embodiment, one possible default value that may be assigned to the Random Velocity Cutoff is 0.98. In this embodiment, a subroutine is performed that uses as input a generated polar working value fragment ejection angle (note that although is referred to as the generated polar working value fragment ejection angle, may be changed/updated if a random number between 0 and 1.0 (X) is greater than a generated random number greater than or equal to the End Fragment Factor and less than or equal to 1.0 (D), as can be seen in FIG. 7B , steps 735 ( a , b)). The subroutine includes instructions for causing a computer to generate a random number greater than or equal to the End Fragment Factor and less than or equal to 1.0 (D) (step 700 in FIG. 7A ) and a random number between 0 and 1.0 (X) (step 705 ). The subroutine includes instructions for causing a computer to compare X to D (step 710 ). When X is less than or equal to D, then the fragment is not considered to be an end fragment. The subroutine includes instructions for causing a computer to exit (step 715 ) the subroutine to step 445 in FIG. 4 when the fragment is not considered to be an end fragment. When the generated random number between 0 and 1.0 (X) is greater than the generated random number greater than or equal to the End Fragment Factor and less than or equal to 1.0 (D), the fragment is considered an end fragment.
The subroutine includes instructions for causing a computer to do the following when the fragment is considered to be an end fragment:
1) generate a random angle greater than or equal to 0 and less than or equal to 180 (step 720 ) Theta1 (θ 1 ); 2) compare Theta1 (θ 1 ) to (step 725 in FIG. 7B ) and, depending upon the comparison, generate and update the value of as follows:
a) When Theta1 (θ 1 ) is greater than or equal to ,
i) generate a random angle Theta2a (θ 2a ) such that Theta2a (θ 2a ) is greater than or equal to 0 and less than or equal to (step 730 a ); ii) update the value of (although there is a small chance the value of will not be changed from its originally determined value as described in FIG. 7 ) to be = to Theta2a (θ 2a ) (step 735 a ), making the end fragment a forward moving end fragment.
b) When Theta1 (θ 1 ) is less than ,
i) generate a random angle Theta2b (θ 2b ) such that Theta2b (θ 2b ) is greater than or equal to and less than or equal to 180 (step 730 b ). ii) update the value of (there is a small chance the value of will not be changed from its originally determined value) to be = to Theta2b (θ 2b ) (step 735 b ), making the end fragment a backward moving end fragment.
3) generate a random number that is greater than or equal to 0 and less than or equal to 1 (Y) (step 740 ); 4) compare Y to the Random Velocity Cutoff (step 745 ) and, based on the comparison, generate a multiplier and update the working value fragment velocity W frag velocity (generated in step 415 in FIG. 4 ) as follows:
a) when Y is greater than the Random Velocity Cutoff,
i) generate a multiplier, m 1a , that is equal to the sin( ) (step 750 a in FIG. 7B ); ii) multiply m 1a and the working value fragment velocity W frag velocity as determined in step 415 in FIG. 4 ; iii) update W frag velocity such that W frag velocity is equal to m 1a multiplied by the working value fragment velocity W frag velocity as determined in step 415 (step 755 a in FIG. 7B ), yielding an updated W frag velocity ;
b) when Y is not greater than the Random Velocity Cutoff,
i) generate a random number Z such that Z is greater than or equal to 0 and less than or equal to 1 (step 749 ); ii) generate a multiplier, m 1b , such that m 1b , is equal to Z*sin( ) (step 750 b ); iii) multiply m 1b and the working value fragment velocity W frag velocity as determined in step 415 in FIG. 4 ; iv) update W frag velocity such that W frag velocity is equal to m 1b multiplied by the working value fragment velocity W frag velocity as determined in step 415 (step 755 b in FIG. 7B ), yielding an updated W frag velocity ;
5) exit (step 760 ) into step 445 in FIG. 4 .
When end fragments are to be generated, the resulting/yielded updated/changed working values W frag comprise the fragment's “fragment performance profile”.
A plurality of fragment performance data structures is configured to store fragment performance data (including the fragment performance profile) for each of the fragments in the current warhead model case segment 515 in FIG. 5 (step 445 in FIG. 4 ). Block 445 represents instructions for causing a computer to store, in the plurality of fragment performance data structures, the fragment's fragment performance profile, i.e., the fragment weight generated in step 410 , the fragment velocity generated in step 415 (and, if applicable, the fragment velocity calculated in step 755 a or b in FIG. 7B ), and the fragment ejection angle generated in step 420 in FIG. 4 (and, if applicable, the fragment velocity calculated in step 755 a or b in FIG. 7B ).
Some embodiments include “field filters instructions” which include instructions for causing a computer to apply a set of field parameters/filters to the data elements that comprise the fragment performance data structures (block 169 in FIG. 1B ). The field parameters/filters are derived from empirical data collected from tests performed for similar types of warheads. The parameters file includes “field” filters, which are used to tailor models to test conditions in the field, and model distribution parameters, which characterize the three fragment distributions and two correlations. The set of field filters is comprised of empirical data obtained from arena warhead tests that have been performed for similar warheads. The results of applying the field parameters/filters to the data elements within the fragment performance data structures are stored as a field performance record (block 350 in FIG. 3 ).
Warhead performance can be tabulated (or visually depicted) as average fragmentation characteristics calculated over designated angular bins (having a pre-determined angular coverage, for example, 5 degree increments) called polar zones. Some embodiments of the invention include instructions for causing a computer to assign fragmentation characteristics to a polar zone (block 345 ) (referred to in this specification, including the claims, as “polar zone accumulating instructions”), i.e., accumulate fragment performance per polar zone by assigning fragment data contained within the fragment performance data structures to a polar zone. The accumulated fragment performance per polar zone data is stored in the fragment performance data structures.
Embodiments of the invention include instructions for causing a computer to decrement the fragment count (block 355 ) for the current warhead model case segment, 515 in FIG. 5A , after each fragment in the current warhead model case segment 515 is processed. Embodiments of the invention include instructions for causing a computer to determine whether all fragments in the current warhead model case segment 515 have been processed (step 360 ), (the decremented fragment count (block 355 )=0). Embodiments of the invention include instructions for instructing the computer to process then next fragment in the current warhead model case segment, 515 in FIG. 5A , when the decremented fragment count (block 355 )>0 (meaning that all fragments in the current warhead model case segment have not been processed). Embodiments of the invention include instructions for causing a computer to decrement the segment count (block 336 ) each time the decremented fragment count (block 355 )=0 (meaning that all fragments in a current warhead model case segment, 515 in FIG. 5A , have been processed).
Embodiments of the invention include instructions for causing the computer to determine whether all warhead model case segments 515 in the warhead have been processed (as determined in step 319 ); all warhead model case segments, 515 in FIG. 5A , in the warhead 510 have been processed when the decremented segment count (step 336 )=0. Embodiments of the invention include instructions for instructing the computer to process the next warhead model case segment, 515 in FIG. 5A , in the warhead 510 when the decremented warhead model case segment>0 (meaning that all warhead model case segments 515 in the warhead 510 have not been processed) (as shown in step 319 in FIG. 3 in FIG. 3 ).
Embodiments of the invention include instructions for causing the computer to determine whether all Monte Carlo iterations have been run (steps 180 in FIGS. 1C and 9A and 179 in FIG. 1C ).
When only one iteration is to be performed, i.e., the initial Monte Carlo iteration run count is not >1 (step 179 ), and all warhead model case segments, 515 in FIG. 5A , have been processed, i.e., the decremented segment count (step 336 in FIG. 3 )=0 as determined in step 319 in FIG. 3 , instructions included in the embodiment cause the computer to generate information/data files based on information/data of the “final run” in the fragment performance data structures. (Note that if only one Monte Carlo iteration is to be performed, the “final run” (referred to in block 184 in FIGS. 1C and 9B ) is the single Monte Carlo iteration.))
When multiple Monte Carlo iterations are to be performed (as input in step 205 in FIG. 2A ) (determined in step 179 in FIG. 9A ), and another Monte Carlo iteration remains to be performed (step 180 in FIGS. 1C and 9A ), embodiments include instructions for causing the computer to save the data from the current Monte Carlo iteration data in computer memory (fragment performance data structures) using any known device and/or manner that will allow the computer to later distinguish between data from different Monte Carlo iterations (block 930 in FIG. 9A ), re-seed the random numbers generators (as shown in 104 in FIG. 1 ), and analyze the warhead again, i.e., the segment loop ( FIG. 3 , and indicated by line 102 in FIG. 1 ), fragment loop ( FIG. 4 , and indicated by line 101 in FIG. 1 ), and correlation loop (indicated by line 105 in FIG. 1 ), are run with re-seeded random number generators. When all Monte Carlo iterations have been executed (as determined in step 180 in FIG. 1C ), embodiments include “iteration averaging instructions” for causing a computer to average the Monte Carlo iterations and store the average in computer memory (step 952 in FIG. 9B ). Some embodiments of the invention include “best fit” instructions for causing a computer to retrieve the average and individual Monte Carl runs, compare the individual Monte Carlo runs to the average, and identify the Monte Carlo iteration that best fits the average performance (block 954 ). Embodiments of the invention include “final run designating” instructions for causing a computer to designate the “best fit” Monte Carlo iteration as the “final run” (block 956 ).
Some embodiments of the invention include instructions for causing a computer to analyze the “final run” (block 184 ) (again, when only a single run/iteration was to be performed, the “final run” is the single iteration) (“analyzing instructions”). Embodiments of the invention include “analyzing instructions” for causing a computer to generate post process information files from the data in the “final run” (step 958 ). The information files include a detailed warhead model case segment data file ( 958 a ), a summary warhead model case segment performance data file ( 958 b ), and a summary warhead model case segment performance by polar zone data file ( 958 c ). The summary warhead model case segment performance by polar zone data file is generated using information in the fragment performance data structures. Embodiments of the invention include instructions for causing a computer to retrieve/recall information in the fragment performance data structures and calculate average fragment characteristics, including, but not limited to, W frag velocity and W frag weight (computed in steps 410 and 415 in FIG. 4 —or where applicable, i.e., when updated using the end fragment generating instructions, in steps 755 a,b in FIG. 7B ) per a pre-determined polar zone based on .
Some embodiments of the invention include instructions for generating text and/or graphics files using the information/data files generated in 958 a - c in FIG. 9B (“user defined format generating instructions”). In another, a user defined format is a standard Joint Munitions Effectiveness Manuals (JMEM) document format file. In another embodiment, a user defined format is a standard JMEM ZDATA format file. Some embodiments include instructions for causing the computer to generate a visual/graphical depiction of the warhead performance on an electronic display. FIGS. 8A , 8 C, and 8 E illustrate one embodiment of a visual depiction of warhead performance taken from a screen shot ( FIG. 10 ) (modified to comply with USPTO figure requirements) of an electronic display of one embodiment of the invention as implemented to analyze one possible 2.75 inch rocket warhead. Note that the nose of the warhead is on the left of the plot (0 degrees polar angle) while the tail is on the right of the plot (180 degrees polar angle). FIG. 8A shows a partial visual depiction a result of one embodiment of the invention, presented as fragmentation performance polar plot from a run for a 2.75 inch rocket warhead. The plot shows fragment count per polar zone (e.g. 90-95 degrees polar angle, 95-100 degrees polar angle etc. in 5 degree increments). FIG. 8C shows a partial visual depiction of the result of one embodiment of the invention presented as fragmentation performance polar plots from a run for a 2.75 inch rocket warhead. This plot shows the average fragment weight per polar zone. The plot shows the results from the current run, (or Monte Carlo iteration). FIG. 8E shows a partial visual depiction of the result of one embodiment of the invention presented as fragmentation performance polar plots from a run for a 2.75 inch rocket warhead. The plot shows the average fragment velocity per polar zone. The plot shows the result from the current run (or Monte Carlo iteration). FIG. 10 is a screen shot of one embodiment of the invention; the screen shot includes most of FIGS. 8A-F . | A method and a computer program product for estimating and predicting the performance of fragmentation devices such as, for example, warheads that are often incorporated as part of a weapon system. | 6 |
BACKGROUND OF THE INVENTION
Related Applications
1. "Address Development Technique Utilizing a Content Addressable Memory", invented by James L. Brown and Richard P. Wilder, Jr., filed on Aug. 24, 1972, having Ser. No. 283,617 and assigned to the same assignee as the instant invention.
2. "Segment Address Development", invented by Bienvenu and filed on May 16, 1974, having Ser. No. 470,496 and assigned to the same assignee as the instant invention.
3. "Data Processing System Incorporating a Logical Move Instruction", invented by Charles W. Bachman, filed on Dec. 13, 1973, having Ser. No. 424,381 and assigned to the same assignee as the instant invention.
4. "Data Processing System Incorporating a Logical Compare-Instruction", invented by Charles W. Bachman, filed on Dec. 13, 1973, having Ser. No. 424,406 and assigned to the same assignee as the instant invention.
5. "Data Processing System Utilizing a Hash Instruction for Record Identification", invented by Charles W. Bachman, filed on Dec. 13, 1973, having Ser. No. 424,391 and assigned to the same assignee as the instant invention.
Field of the Invention
This invention relates generally to data processing system and more particularly to an apparatus and utilizing a data field description.
Description of the Prior Art
Because of the advances in data base systems, it is possible for a broad class of programs to process files of the same data base. In general, these programs have been developed over a period of months and years and represent a large investment in both human and computer resources to bring them to a point of useful productivity.
Under conventional practice, these programs must recognize the exact representations of the data as stored in the data base file or must have the data reformatted. For the latter situation, before the program can operate on the data files, the data is reformatted to a compatible form each time the data is accessed from the data file, i.e., the data is transformed from the format as stored in the data file to the format which the program recognizes. This reformatting is accomplished by subroutines and hence is slow and expensive.
When the records and files used in the data base are defined, they are done so in a form which depends primarily upon the then existing need. Since the art of data handling is not static, additional needs or requirements surface with the problem that the data files may not be in a form which is particularly suited for the new purpose. For example, it is often highly desirous to add new fields to a record, or to change the size or recording mode of some fields. Since the format of the data determines the design of the subroutines, the more versatility desired in the handling of the different kinds of data, the more complicated the subroutine becomes. The main result of these developments is to effectively freeze the original format of the data base files and the programs for extended periods of time. As a consequence, the evolution of data base structures that would normally occur is inhibited. This evolution is highly desirable to permit the data base files to better support the information system activities of the enterprise which they represent.
Historically, instructions have been defined for specific data types. By this is meant that under conventional practice, the attributes of the data field, i.e., the location of the data field, its length, encoding, etc. are determined and at compile time the description of the data is used to create the special instruction. In addition, it may be necessary during the execution of a program to select a combination of instructions for processing data whose characteristics cannot be given beforehand, but are given as a result of some preceding instruction. Thus, it is apparent that such instructions were created to include information based not only on specific data types but also for the data processor which would implement each instruction. If any of the attributes of the data field are required or desired to be changed, or if a different data processor is to be used, the instruction provided is rendered obsolete since the instruction is not capable of handling the new data. As a result, the binding of an instruction by a particular data type has also not allowed evolution of data base structures. What is desired is a system capable of incorporating developments without the attendant problems shown above.
OBJECTS OF THE INVENTION
It is a primary object of this invention to provide a data processing system which overcomes the above recited limitations.
It is a further object of this invention to provide an improved data processing system which is able to operate with a variety of data types from a plurality of sources.
It is another object of this invention to provide a data processing system which can quickly and efficiently utilize data fields in data base files.
It is yet a further object of this invention to provide data independence for data fields utilized in a data processing system by insuring independence of the program being used and independence of the data base file containing the record.
It is yet a further object of this invention to provide a data processing system which allows the separate changing of data files and/or programs with no modification of alteration of the other being required.
SUMMARY OF THE INVENTION
The foregoing objects are achieved according to one embodiment of the invention and according to one mode of operation thereof by providing in a data processing system an instruction format which incorporates data field descriptors describing the attributes and location of the data fields to be processed. In accordance with the instruction, the individual features of the data field descriptor are analyzed and compared by an arithmetic control unit in combination with a control store unit and a control interface adapter. Based on the determination made thereon, the arithmetic control unit carries out the operation specified by the instruction in accordance with the information provided by the data field descriptor. The same instruction may be used for a plurality of different data fields by incorporating different data field descriptors.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features which are characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation together with further objects and advantages thereof may be best understood by reference to the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a didactic view of a data base file;
FIG. 2 is a diagram of various hardware structures utilized in the present invention;
FIG. 3 is a general block diagram of a data processing system utilizing the present invention;
FIG. 4 illustrates a flow diagram of the use of the data field descriptor in accordance with the present invention; and,
FIG. 5 is a block diagram of an embodiment of the invention utilized in the data processing system of FIG. 3 in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
To allow a data processing system to change the form of data in its data base files and still accommodate the programs written for the data base files, a generalized approach to the utilization of data files has been provided. This generalized approach includes the use of purely logical instructions which are function oriented and represent the primative operations on data fields related to data access and control. Since these instructions are not dependent upon particular data types, they allow the possibility of walking, i.e., changing on a periodic basis, a system through a period of time without resorting to radical changes.
In accomplishing the generalized approach, the concept of data independence is used since it makes possible procedures independent of the detailed organization of the data base. As implemented in the current state of the art, data independence requires a concept of two forms of data field representations: (1) the form of the data field as supplied to the program in the processor, and (2) the form of the data field as stored on secondary storage. By utilizing data independence, programs which have been tested at considerable expense are able to be isolated from changes in the recording form, length, or location of data items which would otherwise obsolete them, In addition, data independence permits programs to be compiled with operations on data items for which the form, length, or location is not recognizable at compilation time. Moreover, data independence permits the effective encoding and decoding of data such as to assist in the security of the data itself.
To realize data independence, a data field descriptor is used. By providing a data field descriptor having the description of the data field contents and by permitting the data field descriptor to be integrated into the data processing system, data independence is achieved since the data field descriptor is carried separately from the program. Moreover, the use of a data field descriptor permits format independent instructions (move, compare, add, etc.) to be used since the data field descriptor defines the data field on a day to day basis. Thus, the data field descriptors may be easily altered to incorporate the changes into the data field. As a result, the logical instruction is only concerned with the information as it presently exists and is not limited by the specific data type. The instruction merely has to ascertain the location of the data field descriptor, which, in turn, accounts for the data field variations which were previously required to be included in the instruction itself. The data field descriptor, in combination with the instruction addresses and manipulates the data field at the time that the function of the instruction is being executed, thus, obviating the need for special instructions of conventional practice.
The data field descriptors enable data independence by specifying detailed item attributes. By this is meant, at least, the data fields involved, the type of data used, the length of data and the recording mode. Moreover, the data field descriptor enables the program to treat all data types alike since at execution time it accounts for the variations in the data structure. Thus, the information of the data field descriptor in combination with the instruction automatically determines the operation to be performed. Moreover, the same instruction may operate on different data and/or the same data with different data field descriptors thus providing increased flexibility. This provision of the same instruction used for numerous data types is a significant operation feature.
Since the data field descriptor is provided in a high speed hardware register, specialized subroutines previously required to analyze each field of the record and based upon the determination made therein, to carry out a particular transformation or operation of data are eliminated. Moreover, the subroutine concept which required repeated accesses to main memory by the operating program resulting in excessive memory instructions with a concomitant higher operating time are also eliminated since numerous memory fetches are not required in decoding the data field descriptor by the data processor. As a result, fewer steps and a significantly shorter access time is provided.
Before analyzing the apparatus which utilizes data base files, an examination of the fundamental theory of data management is provided such that a complete understanding of the invention's environment is understood. Three basic concepts of information are conceived by data management. The first type of information is an entity, i.e., a term used to describe a particular type of thing in the real world. An entity may be, for example, a person, a place, etc. With regard to each entity, there is a substructure of information. This information is called attributes of an entity and is the second type of information. Attributes have values peculiar to and describing a particular entity. For example, if describing a person, attributes about the person would be his name, weight, age, etc. The third concept of information is the relationship between entities. For example, a person has a relationship to other people he works with, to people in his family, and many other considerations.
The equivalent information systems concepts for the material world concepts of entities, attributes and relationships, are records, fields and sets. Using the analogy of a person, an entity may be presented by one or more records. A record is an assembly of zero or more fields, i.e., attributes, pertinent to a single entity. A field is the smallest piece of data distinguishable by the system. The records, e.g. the indicia about the person, are assembled into sets which recreate the relationships of the real world. Each of these information system models thus finds a basis in the storage system of a data processor.
When a user defines records and fields, he desires to utilize data in quantities which depend upon the problem. For example, for the employee, to determine his sex, only one or two bits of information may be required. To describe the same employee's education or weight, would take a longer information quantity. In order to store the equivalent data it is important to have units of different size to conveniently discuss and manipulate data. In contrast to this, the data processing system handles the data in a size which is particularly suited for manipulation by itself. While it would be ideal if the data processor would handle information having the same size as required by the user, this is not usually possible. As a result, it is often necessary to transform the description of data in the data files into a description which the program recognizes. Experience has shown this to be a very time consuming process from two aspects. First, there may be a particularized subroutine to convert the data type of a given user into the desired format, and second, there must be numerous accesses by the computer in order to utilize the subroutine.
In addition to optimizing data for particular purposes, a user may express information in a variety of different data types. By data type is meant that different forms may be utilized to express the same information. For example, to express the decimal number 10, in a base of 8 it would be encoded as 12 and in the radix 2, it would be encoded as 1010. Similarly, in computer language it is possible to encode data in a number of different data types. These include alphanumeric strings, bit strings, short logical binary data, long logical binary data, short fixed point data, long fixed point data, packed decimal data, unpacked decimal data, short floating point numbers, long floating point numbers, and extended floating point numbers. In addition, these data types may be encoded in several different codes, e.g. ASCII, EBCDIC, and BCD (binary coded decimal).
With this background, the problem of utilizing data base files is apparent. However, by incorporating a data field descriptor in the addressing scheme of a data processor, the utilization of the data base files is expedited as will be seen by an examination of the following figures.
In FIG. 1, a data structure diagram of data descriptors and data elements is shown. A data processing system 110 has many files, each of which contains a number of pages 100, only one being shown. As used herein, a file is a unit of logical storage which serves as a container for records. A file is subdivided into one or more pages 100. A page, in turn, is a unit of logical storage which is capable of holding one or more logical records.
Associated with the files in the data processing system are file descriptors 101. A file descriptor identifies the file number and page number of the logical file containing the unique information of a user required to run his business. Also included in the system are record descriptors associated with logical records and field descriptors associated with logical fields each being a subset of the former in the hierarchical scheme. Each descriptor provides information concerning the attributes of the logical structure.
In FIG. 1, block number 102 is a page header which denotes information concerning a page of the data file. This information includes the page number, any integrity mechanism and the physical mapping parameters, i.e., the location of the records contained therein. Block number 102 is shown as referencing a plurality of records 103 to 106, record 106 being shown in greater detail.
At the start of record 106 is a blocked out area called a record heading which locates a record descriptor. The record descriptor indicates the record name, record type code, record length, record access rights, etc. of a record. A record 106 is composed of one or more data fields indicated in the drawings as name, department number, pay number, sex. Each field in record 106 is associated with a field descriptor 108. The field descriptor 108 is composed of a number of data field descriptors 108a-x which identify among other things, the field name, field recording mode, field offset within the record, field length, field dimensionality, field access rights, etc. of the record occurrence.
Since the data field descriptors 108a-x describe the data fields, i.e., data about data, they may be incorporated into the page structure thus providing a formatted file. Alternatively, the descriptors 108 may be used on an operating system level basis being individually addressable. Each of these methods is envisioned in the application of the instant invention. Moreover, by maintaining the data field descriptors in the above manners, there is permitted the definition of each file structure with a minimum of interference with other file structures.
When disclosing data, the form of the data disclosed is usually implicitly defined. As an example, in COBOL when a data field is declared, the form of its use is also made known. This may be illustrated as follows. If the first field of the record 106 is a description of a person's sex, the the C field 108 may declare the field to be a bit string having a one bit length. If the second field is a department number of the person, then the X field may declare this as a character string of a certain length. Thus, the array of descriptors illustrated by block 108 provides data field descriptors which identify the attributes of the field.
In view of the fact that many records are similar, the descriptor 108 elucidating features of the data can be used for multiple occurrences. For instance, in a large company, where many thousands of employees are processed by a data processor, the record type code will point to one descriptor 108 which describes a particular format used to record information about each one of these employees. Thus, if there are 10,000 employees, only one descriptor 108 pointed to by the record descriptor is needed to describe the data fields concerning that employee. Moreover, by use of the data field descriptors, to be explained infra, the coordination required to identify the fields is automatically recognized. This coordination may be accomplished in integrated access and descriptor access products which support access to description controlled files, i.e., files where the description of the contents and structure of the data is carried separately from the program thus insuring data independence between the program and the data.
Since a particular program in a data processor 110 may not be anticipating the fields as defined in the user's data base files, it is necessary that the-program provides for its own record and data field descriptors for the same information. As a result, data independence is achieved since the data base provides for the data in one form, but the program may be utilizing the data in a completely different form. This is accomplished through descriptor 112 which defines the attributes of the data. These descriptors are stored such that they are uniquely addressable. In fact, in the system utilized herein, all data field descriptors are provided in a shared address space such that the descriptors can access and manipulate the descriptors of another process that is controlling a mutually shared record. The data fields in descriptor 112 are particularized to an individual application program. These descriptors indicate where in the work area 114 of the data processor to find the field, determine how long this field is, determine its recording mode, and other indicia which will be further explained. The data field descriptors in the data base correspond to those of the work area so that the data field content can be moved back and forth between the work area and the data base with the required reformatting.
Inherent in the above description is the basis that the data field descriptors 108 defined in the data base are format dependent upon the type of information defined by the data base administrator. Similarly the work area descriptors 112 are format dependent upon the types of information anticipated by the application program. In the discussion which follows, attention is centered about the descriptor fields describing the attributes of the data fields and purely logical instruments which in conjunction with the data field descriptors, handle the fields in the transferral from the data base files to the application program.
Referring now to FIG. 2, a logical instruction 200 which uses the data field descriptor 108 is shown. For didactic purposes, the instruction 200 is shown as referencing two fields, however, instruction 200 can reference one, two or more fields. Thus, one field would be referenced for a hash type instruction, two fields for a move, compare, etc. type instruction; and three fields for an add, subtract, etc. type instruction.
The instruction 200 can be used with any encoding scheme since the necessary features of the encoding scheme are provided to the instruction by the data field descriptors. Thus instruction 200, which can specify different types of operations to be performed on data (i.e., move, add, compare, etc.) provides for obtaining data field descriptors as part of the operation of fetching operands. Each data field descriptor 108 obtaind by the instuction 200 describes the format of a corresponding field of data 106 on which the instruction is to operate. Thus, formats of data files need not be described in the programs themselves. Moreover, the instructions of the program can remain the same even though the data field 106 itself may change with time.
FIGS. 2a and 2b show an instruction format 200. More specifically, FIG. 2a shows a 32 bit format with the first 8 bits as an operation code, i.e., OP code. The OP code is the high order byte of an instruction and is used to identify a particular type of instruction. In this instance, the OP code may indicate a move, add, subtract, multiply, divide, compare, or hash type instruction. The next 4 bits, i.e., bits 8 to 11 are shown as MBZ which indicates that these bits must be zero. Bits 12-31 identify the first address syllable AS1 which is a logical representation of the address of the operand in memory.
For the particular type of operation utilized herein, the address syllable has its first bit, i.e., bit 12, set to a binary ONE. This bit is utilized to specify the indirect addressing mode. The data field descriptor is developed via this indirect addressing mode. While there are many alternative methods for indirect address development, (see, for example, U.S. Pat. No. 3,412,382 issued to Couleur et al, dated Nov. 19, 1968) the preferred embodiment would be as follows. In the address syllable would be a field which identifies a base register containing a segment number and an offset. The segment number references a table which provides a segment descriptor locating the segment containing a data descriptor. This data descriptor is identified by adding the offset in the base register to a displacement field in the address syllable. Thus, the location within the segment identified via the tables is provided. This data descriptor may include up to 3 words, the first word identifies the actual operand desired and the second and third work, if necessary, describes the attributes of the operand.
More specifically, the first word identifies a base register which again contains a segment number and an offset. After the segment number is referenced to tables to provide a segment descriptor locating the segment containing the operand, the offset in the base register is added to a displacement in the first word thus identifying the exact location of the operand within the segment.
FIG. 2b shows the second word of instruction 200, the second word having bits 32-63. Bits 32-35 designate a general register of the data processor 110 into which the first word developed by the address syllable is placed. Bits 36-39 indicate a second general register into which the first word developed by the second address syllable AS2 is placed. The second address syllable is shown by bits 44-63. As was the situation for the first address syllables, the second address syllable has its first bit (i.e., bit 44) set to a binary ONE to indicate indirection.
While variations of this instruction are provided and are discussed infra, in the particular instruction specified, two address syllables are utilized. For purposes of clarity, the first address syllable will be described as referencing the source field in memory and the second address syllable will be described as referencing the destination field in memory.
Each address syllable AS1 and AS2 references a data field descriptor. The first part of the data field descriptor includes only one data descriptor from those shown in FIGS. 2c to 2e as 202, 204, 206 respectively. Each of the first part of the data descriptors referenced has a tag portion in the first two bit locations. This tag portion has a code 01 which indicates that the second part of a data field descriptor, i.e., an extended data descriptor, has been specified. Moreover, the 01 tag allows factoring of the attributes of the data field. The reason for this is based on the desirability of showing the data field descriptors having certain attributes across a set of data item descriptors. Thus for example, 1000 employees can be factored for one data field descriptor. In addition, the use of the 01 tag allows the data field descriptor to be integrated into the balance of the control structure of the data processor 110. The remaining parts of the data descriptor in FIGS. 2c-2e identify the location of the operand to be processed. Thus, the STN and STE identify the segment and tables which are utilized in conjunction with the displacement to define the operand's location. For this feature, the above cited indirect addressing mode should be noted.
The extended data descriptor, i.e., the second part of the data field descriptor, contains at least one more word 208 as shown in FIG. 2f. This second word 208 contains information concerning the attributes of the data field in the data base file or the data field of the data processor.
In extended data descriptor 208, bits 32 to 34 define the field origin of a bit field used for the situation of bit addressing. Bits 36 and 38 of extended data descriptors 208 define array control on the data field. The format of the array control bits is as follows: Bit 36 is the IX bit or array index control bit; Bit 37 is a UB bit or upper bound control bit and bit 38 is the MPY or multiply control bit. If bit 36 contains a binary ZERO, then the extended data descriptor is describing an elementary data field. If it contains a binary ONE, the descriptor points to data in an array of data field and an index register specified in the address syllable, at bits 17 and 19, pointing to the descriptor is used for address development. If bit 37 is a binary ZERO, no upper bound check is performed. By an upperbound check is meant that the number of array elements must be within a certain size. If bit 37 is a binary ONE, the adjusted index must be less than or equal to the value of the limit field as defined in the second word of the extended data descriptor. If the value specified by the index register exceeds the limit, than an exception condition arises. If bit 38 is a binary ZERO, the adjusted index is used unmodified as a byte offset. If bit 38 is a binary ONE, the adjusted index is multiplied by the value of size field (in bytes) as defined in the second word of the extended data descriptor.
Bit 39 of extended data descriptor 208 provides for an alterability indicator bit. If it is a binary ZERO, a write operation may be performed on the data field described by the data field descriptor. If it is a binary ONE, the data field is not able to be written.
Bits 40-63 of extended data descriptor 208 define the attributes of the data field in the data base file. More specifically, bits 40-47 define the field data type. The data type is shown by an eight bit field indicating the type of data encoding. For illustrative purposes, a typical encoding may be as follows. For a binary code of 0000 0000, an alphanumeric string is indicated, for 0000 0001 an unpacked decimal (8 bits per decimal character) is indicated; for 0000 0010, a packed decimal (4 bits per decimal character) is indicated; for 0000 0011, a character string (8 bits per character) is indicated; for 0000 0100, unsigned short binary data (16 bit binary integer) is indicated; for 0000 0101, a signed short binary data (15 bit signed binary integer) is indicated; for 0000 0110, an unsigned long binary data (32 bit binary integer) is indicated; for 0000 0111 a signed long binary data (31 bit signed binary integer) is indicated; for 0000 1000, a short logical binary data (16 bits) is indicated; and, for 0000 1001, a long logical binary data 32 bits is indicated. The field data type codes from 0000 1010 to 1000 0000 may indicate a type code reserved for future expansion and may be currently illegal to use. For encoding of 1000 0000 to 1111 1111 there may be indicated data types available for software use. Each data type encoded may be used such that if valid and compatible a transformation may be performed by the data processor's apparatus. Data type validation consists of matching the type specified in the data descriptor with the type specified in the instruction for which address development is being performed.
Bits 48-55 define the key field attribute of the data structure. The key field is a description of certain features for a particular data type structure. Thus, the key field provides a secondary imposition of requirements upon the data type. The key field may contain information concerning different types of codes, e.g. ASCII, EBCIDIC or BCD or scaling factors, e.g. dollars versus dollars and cents or dimensional analysis, e.g. pounds, kilograms, etc. In operation, if the scaling factor of the data field presented to the application program from the data base file contained a millions category and if the data processor were using a normal scaling factor, there would be a difference in the scaling factors such that operation on the decimal number was not possible without conversion even though the two data types were similar. With respect to dimensionality, different encoding schemes are recognized. For example, the color teal blue may be encoded by its name, by a given number of Angstroms, or alternatively, it may be optimized on encoding by a particular user. Since each form of encoding is describing the same thing, the key field would indicate this relationship. Conversely, the dimensionality factor would not permit a field scaled as metric tons to be moved to a field scaled in units of time, distance, or any unit other than weight.
Bits 56-63 of word 208 are an eight bit length description of the data structure. The length description identifies the length of the operand. For data field operability, the operand's length may meet the following conditions: first, for a byte string, the length must be less than or equal to 256 bytes, second, for a decimal string, the length must be less than 32 digits. If the length exceeded these limits, an illegal data exception would result.
FIG. 2g shows the second word 208 of the extended data descriptor. This word is present and fetched only if the bits 37 and/or 38 of the first extended data descriptor word are a binary ONE. More specifically, the limit field, i.e., bits 64-79, exist if the upper bounds, i.e., bit 37, is equal to a binary ONE. The limit field specifies a 16 bit positive integer which is equal to the maximum number of items in the array. A lower bound of one is assumed for the array for convenience. The contents of the index register specified in the address syllable must never be less than 1. Bits 80-95 of the second word of the extended data descriptor are a 16 bit positive integer which specify in bytes the size of an item in the array. This size indication exists if bit 38 is a binary ONE. The size field indicates that the positive integer is to be multiplied by the adjusted index. When so indicated, the previously described field are checked and used in computing and calculating the computed index, T, in the following manner:
TABLE I
a. (IXR) is the contents of the index register specified in the Address Syllable. (See patent on Segment Address Development cited earlier.) (Treated as 32 bit 2's complement integer.) (IXR specifies a number of items.)
b. (IXR) > 0 (This check is always made.)
c. I ← (XIR) - 1 (Creates adjusted index I.)
d. I < LIMIT (Extended to 32 bits; performed only when UB = 1.)
e. T ← I * SIZE (Performed only when MPY = 1; If MPY = O, T ← I.) I * SIZE is the computed index and is always in bytes.
f. Segment relative address ← Displacement (word O) + T (+ OFFSET of base register if extended descriptor is ITBB.) (See patent on Segmented Address Development cited earlier.) This computed index T identifies the byte which is under consideration.
As will be subsequently seen when describing the apparatus which utilizes the data field descriptor, there are three categories into which the development of the data field descriptor may reside. First, the data field descriptor may be completely hardware supported such that all processing of the data field descriptor is handled by the apparatus shown in FIG. 3 and 5. This occurs for the vast majority of situations. Second, the data field descriptor may be hardware supported but software intervention is required in order to complete the operation. This situation would occur where legal data types are recognized but different key fields are provided. In the example above, re the scaling factor, the software would be required to change the scaling factors such that they were equal. Then the hardware operation could proceed normally. Software intervention is indicated by a condition code of three which will be subsequently explained. Third, the data field descriptor in one of the significant fields is illegal, this situation causes an exception condition which the software handles. Further examples of specific instances wherein this situation arises are shown in FIG. 4.
The explanation of the operation of the instruction 200 and the data field descriptors it accesses will be better understood when viewing the block diagram of FIG. 3 which shows a data processing hardware system which utilizes the invention.
Referring to FIG. 3, a main memory 301 of data processor 110 is comprised of four modules of metal-oxide semiconductor (MOS) memory. The four memory modules 0-3 are interfaced to the central processor unit CPU 300 via the main store sequencer 302. The four main memory modules 0-3 are also interfaced to the peripheral subsystem such as magnetic tape units and disk drive units (not shown) via the main store sequencer 302 and the input/output controller, i.e., IOC 320. The main store sequencer gives the capability of providing access to and control of all four memory modules. Because the main storage sequencer 302 can overlap memory cycle requests, more than one memory module 0-3 may be cycling at any given time. The CPU 300 and the buffer store memory 304 and the IOC 320 can each access a double word (8 bytes) of data in each memory reference. However, in a CPU memory access, either the four high-order bytes or the four low-order bytes are selected and only four bytes of information are received in the CPU 300.
Operations of the CPU are controlled by a read only memory ROM, herein called the control store unit 310. (Control store units for implementing the invention are found in a book entitled Microprogramming: Principles and Practices by Samir S. Husson and published in 1970 by Prentice Hall Inc. Other typical control store units are described in U.S. patent to Leonard L. Kreidermacher, having U.S. Pat. No. 3,634,883 issued Jan. 11, 1972 and assigned to Honeywell Inc). Each location in the control store memory 310 can be interpreted as controlling one CPU cycle. As each location of control store is read, its contents are decoded by micro-op decode functions. Each micro-op decode function causes a specific operation within the CPU to take place. For example, control store data bits 1, 2, and 3 (not shown) being decoded as 010 could bring high a micro-op decode function that causes an A register (not shown) to a B register (not shown) transfer. Because each control store memory location may contain 30 - 80 bits, many micro-op decode functions can be brought high for each control store cycle.
By grouping locations, control store sequences are obtained that can perform a specific CPU operation or instruction. As each instruction is initiated by the CPU 300, certain bits within the op-code are used to determine the control store starting sequence. Testing of certain flops (not shown) which are set or reset by instruction decode function allows the control store memory to branch to a more specific sequence when necessary.
The control store interface adaptor 309 communicates with the control store unit 310, the data management unit 306, the address control unit 307 and the arithmetic logic unit 312 for directing the operation of the control store memory. The control store interface adapter 309 includes logic for control store address modification, testing, error checking, and hardware address generation. Hardware address generation is utilized generally for developing the starting address of error sequence or for the initialization sequence.
The buffer store memory 304 is utilized to store the most frequently used or most recently used information that is being processed by the CPU 300. The buffer store memory is a relatively small, very high speed memory which contains 128 columns and 2 rows, referred to as the upper row and the lower row. It is logically divided into preset blocks which are uniquely addressable. These blocks are called pages and each page of memory contains 32 bytes of information. A particular page may be addressed by the most significant 16 bits of the main memory address, the least significant five bits being used to address a particular byte of information within the page. Pages may be transferred from main memory to buffer store memory with a column assignment maintained --i.e., a page from column one in main memory is always transferred into column one in the buffer store memory. However, whether the information is placed on the upper or lower row of the column depends on availability. Therefore, for each column of main memory pages (for instance for a system having 256K to 2 megabytes in main memory 301 there would be 64 to 512 pages), there are two pages in buffer store. For example, column 37 in buffer store memory 304 may contain any two pages of information from column 37 in main memory. The two pages of information contained in the buffer store column at any given time depend on which pages have been most recently accessed by the CPU --i.e., the two most recently accessed pages typically reside in the buffer store memory 304.
Whether a given page of information is contained in buffer store 304 can be determined only by examining the contents of the buffer store directly 305. The buffer store directly is logically divided in the same manner as buffer store, however, instead of pages of information, each column in the buffer store directory 305 contains the main memory row address of the corresponding information in the buffer store 304. For example, if column 0 of buffer store 304 contains page 20 in the lower row and page 0 in the upper row, the buffer store directory contains 10100 and 00000 in the lower and upper row respectively. Thus, by accessing the buffer store directory 305 with the column number and comparing the requested row number with the row number contained in the buffer directory location, the CPU can determine whether a given page is contained in buffer store memory 304.
The data management unit 306 provides the data interface between the CPU 300 and main memory 301 and/or buffer store memory 304. During a memory read operation, information may be retrieved from main memory or buffer store memory. It is the responsibility of the data management unit 306 to strobe the information into the CPU registers at the proper time. The data management unit also performs the masking partial write operations.
The instruction fetch unit 308 which interfaces with the data management unit 306, the address control unit 307, the arithmetic and logic unit 312 and the control store unit 310 is responsible for keeping the CPU 300 supplied with instructions. The unit attempts to have the next instruction available in its registers before the completion of the present instraction. To provide this capability, the instruction fetch unit 308 contains a 12-word instruction register (not shown) that normally contains more than one instruction. In addition, the instruction fetch unit, under control of the control store 310, requests instructions from main memory 310 before the instruction is actually needed, thus keeping its 12-word instruction register constantly updated. Instructions are thus prefetched by means of normally unused memory cycles. The instruction fetch unit also decodes each instruction and informs the other units of the instruction's length and format.
The address control unit 307 communicates with the instruction fetch unit 308, the buffer store directory 305, the main store sequencer 302, the arithmetic logic unit 312, the data management unit 306, and the control store unit 310 via the control store interface adapter 309. The address control unit 307 is responsible for all address development in the CPU. All operations of the address control unit, including transfers to, from, and within the unit, are directed by control store micro-ops and logic in the unit. The normal cycling of the address control unit depends on the types of addresses in the instruction rather than on the type of the instruction. Depending on the address types, the address control unit may perform different operations for each address in an instruction.
The address control unit 307 also contains an associative memory that typically stores the base address of the eight most recently used memory segments, along with their segment numbers. Each time a memory request is made, the segment number is checked against the associative memory contents to determine if the base address of the segment has already been developed and stored. If the base address is contained in the associative memory, this address is used in the absolute address development, and a considerable amount of time is saved. If the base address is not contained in the associative memory, it is developed by accessing the main memory tables. However, after the base address of the segment is developed, it is stored in the associative memory, along with the segment number, for future reference.
Interfacing with the address control unit 307, the instruction fetch unit 308 and the control store unit 310 is the arithmetic logic unit 312 which is the primary work area of the CPU 300. The arithmetic logic unit's primary function is to perform the arithmetic operations and data manipulations required of the CPU. The operations of the arithmetic logic unit are completely dependent on control store micro-ops from the control store unit 310.
Associated with the arithmetic logic unit 312 and the control store unit 310 is the local store unit 311 which may be comprised of a 256 location (32 bits per location) solid state memory and the selection and read/write logic for the memory. The local store memory 311 is used to store CPU control and maintainability information. In addition, the local store memory 311 contains working locations which are primarily used for temporary storage of operands and partial results during data manipulation.
The central processing unit 300 typically contains eight base registers located in arithmetic logic unit 312 which are used in the process of address computation to define a segment number, an offset, and a ring number. The offset is a pointer within the segment and the ring number is used in the address validity calculation to determine access rights for a particular reference to a segment.
The IOC 320 is the portion of the data processing system that completes a data path from a number of peripheral subsystems to main memory. It provides the path through which peripheral commands are initiated, and it controls the resulting data transfers. The IOC can handle a maximum of 16 channel control units, and each channel control unit can accommodate one peripheral control unit. It is these peripheral control units which provide to the central processing subsystem one set of the data base files.
Referring now to FIG. 4 there is shown a flow diagram illustrating the steps which are used in processing the data field descriptors. The operations illustrated by FIG. 4 when read in conjunction with FIGS. 3 and 5 explain the overall timing and function of the system. FIG. 5 is a schematic diagram which shows the mechanisms for the transfers and manipulations of the data field descriptor at the system level. When FIGS. 3 and 5 are read in conjunction with the FIG. 4 flow chart, the operation and procedure of the system incorporating the data field descriptors will be understood.
Since the present invention pertains to data processing systems, the description thereof can become very complex. To prevent undue burdening of the description with matter within the knowledge of those skilled in the art, a block diagram approach has been followed, with a functional description of each block and specific identification of circuitry it represents. The individual engineer is free to select elements and components such as flip-flop circuits, shift registers, etc. from his own background as from available standard references such as "Arithmetic Operations in Digital Computers" by R. K. Richards, (Van Nostrand Publishing Company), Computer Design Fundamentals by Chu (McGraw-Hill Book Company, Inc.) and Pulse, Digital and Switching Waveforms by Millman and Taub (McGraw-Hill Book Company, Inc.). Moreover, most of the details that are relatively well known in the art will be omitted from this description. For example the transfer of information from one register to another under the operation of a control store microprogram unit is well known and is only generally indicated herein. Illustrations of single lines which may, in fact, represent plural lines for parallel transfers is well understood by those of skill in the art. Even though details are eliminated, the basic description of the entire system given in FIG. 3 will enable one skilled in the art to understand the environment in which the present invention is placed. Moreover, the same reference numerals have been used to designate corresponding elements throughout the respective use of the drawings thereby facilitating a ready understanding of the relationship therebetween.
Referring now to FIG. 4, numeral 400 indicates the beginning of the operation to utilize the data field descriptor. At this time the instruction 200 shown in FIGS. 2a and 2b is stored in the instruction register 500 of instruction fetch unit 308 shown in FIGS. 3 and 5. The operation code is detected by the control store interface adapter 309 which in turn enables control store unit 310 to provide for a series of tests to be performed upon selected bit fields of the instruction. These tests are conducted by microinstructions generated from the control store unit 310. The results of these tests are detected by control store interface adapter 309 which, depending on the tested results, may modify the next microinstruction fetch such that a related microinstruction incorporating the detected condition is generated. As is evident, a microbranch technique is provided wherein the conditioned signals received by the control store interface adapter are translated into a direct address in the control store unit 310. The operation resulting establishes a direct path for subsequent data transfers taking into account the previously detected condition. The above sequence of events occurs for each diamond illustration in FIG. 4 and is not hereafter described in complete detail. The microinstructions enable the steps shown to be quickly accomplished. These microinstruction features are further elaborated in U.S. Pat. No. 3,634,883 issued to Kreidermacher, Jan. 11, 1972 and U.S. Pat. No. 3,560,993 issued to Schwartz on Feb. 2, 1971, both assigned to the same assignee of this invention.
In step 402, bit fields 8-11, 35 and 39-44 are tested for binary ZEROS. These tests are sensed by hardware circuitry within the control store interface adapter 309 with the results controlling the operation of the control store unit 310. If the tests are successful, i.e., if the fields have binary ZEROS, then step 404 requires the testing of bit fields 12 and 44 which are the first bits of each of the address syllables. These fields are tested for binary ONES and indicate whether indirection is required. In the present situation, indirection is required since the address syllable has a 01 tag which identifies a data descriptor which is obtained by indirection.
In practice, steps 402 and 404 are executed simultaneously. If any of these fields are not present, then an illegal format field exception as shown in Step 406 is enabled which causes the control store unit 310 in combination with the control interface adapter 309 to provide for a hardware exception routine. This would be accomplished by a branch in the control store unit which would send a message to a routine such that the routine would know what kind of exception has occurred and unique information concerning the exception condition.
Bits 35 and 39 of Step 402 are set to binary ZEROS since two general registers are required for each of the address syllables. By being set to a binary ZERO the next general register is able to be used. Two general registers are required since one register stores the effective address as developed from the address syllable and the second register stores the first word of the extended data descriptor. Thus, four general registers will be utilized for the development of the instruction address syllables in FIGS. 2a and 2b.
Once it has been ascertained that an extended data descriptor is to be developed, step 408 of the flow chart is performed.
Step 408 indicates that address development is to be performed on each address syllable presented, i.e., bits 12 to 31 and bits 44 to 63 of instruction 200. In the present situation, the address syllable is used to reference a data descriptor including a first word from the group of words shown in FIGS. 2c and 2e called an effective address.
The first word has a tag field of 01 indicating that in addition to pointing to the operand, the data descriptor has a length greater than one word. These additional words, i.e., extended data descriptors shown as 208 describe the attributes of the operand being accessed by the first word. Thus, for this particular effective address development, the descriptor indicated by the indirection bit obtains a data field descriptor.
The first word of the data descriptor also contains information pointing to the location of the segment containing the operand and a relative displacement to indicate where in the segment the operand is located. By address development in the arithmetic and logic unit, the absolute address of the operand is computed and then used to access main memory. For the situation wherein 1000 employees are represented, the same data descriptor would be referenced, but this further address development would locate the operand of each of the 1000 employees by changing the contents of the base register to locate all of the 1000 operands. The effective address, i.e., the first word, will hereinafter be referred to as X1 and should be distinguished from the address syllable and the operand since each is stored in a different unit in the central processing subsystem.
In step 410, the first word which contains the effective address as shown in one of the FIGS. 2c-2e is stored in register 504 of the address control unit 307. The control store unit 310 in conjunction with the control store interface adapter 309 then tests as shown in step 410 whether the tag of the data descriptor has as its first two bits 01. These tab bits identify a data field descriptor. If the tag is correct, the first word of the extended data descriptor is read from memory. This word is read either from the main memory 301 or from the buffer store memory 304 as explained earlier. Once this word is read, it is brought into the data management unit via the DN register 502. This is a 32 bit word 208 shown in FIG. 2f. This word is then transferred from the data management unit 306 to the local store unit 311 and is stored in a working register in scratch pad memory 506. The next microinstruction transfers this first word of the extended data descriptor to a register AC 508 where a test is then performed upon the 3 bit array field, i.e. bits 36-38, to determine whether or not a second word of the extended data descriptor should be fetched. This second word is present and is fetched only if bits 37 and/or 38 of word 1 are equal to a binary ONE. This word would then be read from main memory 301 and/or the buffer store memory 304 and transferred to the data management unit 306 in the DN register 502 from which it is subsequently transferred to another working register in the scratch pad memory 506 contained in the local store unit 311. The word contained in the working location of scratch pad memory 506 is then held there until it is needed to determine the particular information about the data field of the data base file.
The same operations as described above are then performed for the second address syllable, the sole difference being the effective address from the address syllable is called X2 and second extended data descriptor is stored in AE register 510. For ease of explanation, it is assumed that only the first word of the extended data descriptor is required.
If the test on the tag of the final descriptors were unequal to 01, then the control store unit 310 would branch to an exception condition which would specify an illegal data descriptor exception and perform much in the same manner as the illegal format field exception except that different unique information would be provided to the system.
With respect to the AC register 508 and the AD register 510, it is possible to select any byte from either of these units to perform tests thereon. This can be accomplished by any well known selector mechanism 518 accessing any byte in the AC or AD registers or by shifting the contents of the AC and AD registers and then transferring the bytes. The selector mechanism is not shown in detail since not only is it well known in the art, but also to describe it would unduly burden the description.
In step 414, the above feature is utilized such that the key field from the first extended data descriptor word resident in the AC register and the key field from the second extended data descriptor word resident in the AD register are transferred to an AA register 512 and an AB register 514, respectively. The AA and AB registers are part of a byte calculator 516 which performs simple parallel addition and subtraction in accordance with the micro-operations provided by control store unit 310. Byte calculator 516 can be any parallel adder or subtraction unit well known in the art. As stated earlier, the key fields are bits 48-55 of the first word of each extended data descriptor.
Under the control of the control unit 310, the contents of the AA and AB registers are transferred to adder 522 which performs a subtraction on the key field of the two words. If the value of the two key fields are not equal, this result is fed to the control store interface adapter 309 which enables the control store unit to branch to a termination routine as shown at step 416. This would be accomplished by setting a condition code into a status register 517 in the arithmetic and logic unit to a binary value of 3. A condition code of 3 indicates that intervention is required in order to complete the operation. This value would then be interpreted by the control store unit 310 such that the word X1 and the first word of the extended data descriptor associated with the first address syllable, and word X2 and the first word of the extended data descriptor associated with the second address syllable, are transferred to the general registers in address control unit 307 as shown in step 416. However, with unlike key fields, it is possible, for example, for a routine to correct the unfavorable conditions by transforming the scaling point factor or the particular code information into a common format, and enable the remaining steps to be completed.
If a binary ZERO is generated from the byte adder 510 to the control store interface adapter 309, then it is known that the key fields match. In response to this, the control store unit 310 provides for a test of the alterability of the second operand as shown in step 418. This test may be accomplished by shifting the contents of AD register 510 such that bit 39 is in the first position of the register. The test is then performed under control of the control store unit and the results indicate whether or not the location specified is able to be written into. For example, if a code was used which was inimical to the data processing system, the A1 or alterability bit would be set to a binary ONE indicating that the data field may not be written into the second operand. If this condition existed, an illegal data type exception as shown in step 420 would be developed by the control store unit.
Subsequent to performing the alterability test, the control store unit 310 performs a test operation on the data types, i.e., bit positions 40-47 of the first word of each extended data descriptor. In step 422, the data type associated with the first address syllable is read from AC register 508 into register AA 512 via the selector mechanism 518 of the arithmetic and logic unit. Concurrently, with this a constant would be loaded into the AG register 520. The constant is within the ranges of the illegal data types. A subtraction operation is then performed between the AA register and the AG register by adder 522. The result of the subtraction determines whether or not the first operand has a legal data type.
For step 424, a similar operation for the second operand is performed with the bits 40-47 of the second extended data descriptor selected from register 510 and placed into AB register 514. If the subtraction from the constant in the AG register 520 indicates an illegal data type, then the data processing system is notified via an illegal data type exception as shown in step 420. This exception corresponds to the operation in step 406 and step 412.
If both data types are legal, then step 426 of FIG. 4 is executed. This step is accomplished by control store unit 310 generating a new constant into AG register 520 with registers 514 retaining the same information. A subtraction operation is performed by logic 522 between AA registers 512 and AG register 520. If the value is zero or greater than zero, the termination procedure of step 416 is performed. If the value is less than zero, a legal data type able to be executed by the hardware is recognized.
The same operation for the second extended data descriptor is then performed in step 428 with the unaffected contents of AB register 514 subtracted from the same constant in AG register 520. If the result provided by logic 522 is less than zero, then step 430 is sequenced. If the result is zero or greater than zero, then the condition code would be set to three in status register 517 and the general registers explained in step 416 would be loaded. It is noted that in this condition, the second word of the extended data descriptor for each address syllable is lost since the routine would not be concerned with the length and size description which the second word in the extended data descriptor provides.
At step 430, it is known that the data types are legal, and that the hardware may contain the requisite features to deal with the data types. Step 430 determines whether the data types are compatible. At this point in time, the control store unit 310 determines the data type of the first and second operands. It does this by first loading a constant into the AG register 520 and subtracting the constant from the data type loaded in the AA register 512. When a zero is tested by the control store interface adapter 309, the control store unit 310 branches to a microinstruction to test what the second data type is. The control store unit now recognizes the first data type. The same operation occurs for the testing of the second data type which is stored in AB register 514. Upon determining what the second data type is, the control store unit is now cognizant of each data type. According to this information, the control store unit does a branch operation which enables the reformatting, if necessary, of the data type to be made. This reformatting may be accomplished by sending the data to a translation device which provides a compatible data type. In addition, the reformatting feature may be different for each data processing system. For example, conversion from a packed decimal 0000 0010 to an unpacked decimal 0000 0001 may be available in all the data processing system. However, a conversion from a signed short binary data 0000 0101 to a signed long binary data 0000 0111 may be provided in only a few data processors. The compatibility types are flexible enough to be provided for a wide range of usage. This results since the logical instruction is not fixed, i.e., bound, until execution time and at that time incorporates the data field descriptors which account for the encoding differences.
Once the control store unit has determined that the data types are compatible and that a transformation may occur, step 432 of the flow chart is executed. Step 432 is a general purpose purely logical instruction which may be an add, subtract, multiply, divide, move, compare and/or hash operation. This logical instruction is performed on the total information identified by the instruction, i.e., each field has a descriptor and there may be one to three fields depending on the type of instruction. When the instruction is executed, the data field descriptors automatically account for the variations in the data fields. Previously, this function had to be performed by a specialized subroutine written for each individual data type.
Upon completion of the instruction in step 432, the next instruction in the instruction fetch unit 308 is sequenced. This completes operation on the specific operand of the data base file.
The automatic accounting feature utilized by the logical instruction includes a translation to compatible formats of the data fields. This is easily accomplished through programmable read only memories (PROMS). In addition, these PROMS are able to be utilized such that the results are returned to the original representations. For particularized examples of the transformations of the data fields in accordance with the data field descriptors, reference should be made to the co-pending applications of Charles W. Bachman previously cited.
For ease of description, the above instruction has been shown to be utilized for a data base file and an application program. However, there are at least five applications which presently may utilize data field descriptors. The source field and/or destination field may be a data file from a communication facility, a data base of a user or the internal storage of the data processor itself. Thus, the five applications provided are (1) from a communication facility to the data processor, (2) from a data base to the data processor, (3) from the data processor to the data processor, (4) from the data processor to the communications facility and (5) from the data processor to the data base.
Although a data field descriptor finalizes the information that the instruction operates on, the actual instruction has great versatility. Thus, the instruction operates differently on the same data fields if another or different data field descriptor is accessed. In essence, this would be accomplished by changing the address syllable and offset in the instruction itself thus referencing a different data descriptor which through its displacement may reference the same or different data fields. In addition, the instruction can operate on different data fields with the same data field descriptors. This would be accomplished by other instructions (not shown) determining that more records are to be processed. The reference to the new operands would be made by changing the displacement in the base register. The next absolute address development would then provide the new data since it provides a different address. As a result, the same instruction would operate on a different data field. This flexibility of the instruction allowing different forms to be utilized is a primary feature in the invention since the same functionality provided by the instruction is able to be used with a great variety of differently encoded data fields thus obviating the limitations described earlier. Moreover, by using data field descriptors not only may the same instruction be constantly used, but the data field descriptor may be changed to a currently more desirable form, thus enabling the evolution of the data base structure. This results since the data field descriptor which addresses and manipulates the data field is part of the control mechanism of the data processor and may be rewritten at any time to describe the new form of the data fields.
Moreover, the instruction can also be used in a hybrid situation wherein only one portion of the logical instruction uses the data field descriptor. As was explained earlier, the prior art in preparing the instruction required information concerning the attributes of the data fields. With this information, the instruction which could carry out the intended operation was then provided. Thus, in creating the instruction, the features of the data field were provided. A logical instruction utilizing a data field descriptor may be provided in combination with an instruction of this type. For example, the source data field and its attributes may be provided in the instruction whereas the destination field may be the logical portion of the instruction previously described and incorporating the data field descriptor. In similar manner, the source field may be the logical portion of the instruction and the destination field may have its features provided by the instruction. The third situation is the one described previously wherein both the source and destination fields are described by a logical instruction incorporating the data field descriptors. Thus, the limitation of preparing instructions based on the form of the data is effectively removed. Even if the form of the data field changes, the logical instruction and hence application program is not obsoleted since the instruction functions regardless of the data type or encoding given. This results since the data field descriptor is changed for the new data and the instruction does not operate on the data field descriptor until execution time. Thus, the nature of the data itself is, in every case, revealed only at execution time allowing the changes of the data fields through time to be made without having to reflect in the program the changes made in the data files. Economy is thus provided in not having to rewrite or retest the program. In the hybrid situation just described, the versatility is limited since the above changes would have to be made for the part of the instruction not dealing with the data field descriptor.
Moreover, the versatility of the instruction is enhanced by the ability to successively access data fields and perform its intended operation. For example, if it is required to move ten data fields, the same move instruction may be accessed for each field. Thus, by other means (not shown) the offset of the address syllable would be changed. However, the logical move instruction would account for the different encoding schemes at execution time via the data field descriptors accessed. Thus the ability to change the encoding schemes from execution to execution is another primary feature recognized by this invention. The well known loop used for moving data fields in the prior art would be applicable for moving successive fields but instead of requiring different move instructions based on each data field only one move instruction is necessary. | A data field descriptor extends the flexibility of operand accesses by defining the attributes of a data field with regard to length, location and form of data representation at execution time. This delay of binding the operand accesses until execution time supports both data independence and security by permitting programs to be compiled without any restrictions imposed by the attributes of data fields. At execution time the necessary information is provided through a register so that the data field information may be correctly processed. With this feature a program is permitted to survive the change in formats of its input and output files without repeatedly undergoing the expensive operation of compilation. Also permitted is processing of files containing data field values which are not uniformly formatted throughout the file but which are self-defining through a data field descriptor. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to improvements in microwave power amplifiers.
Modulations presently in use in radio links, essentially Quadrature Amplitude Modulation (QAM), impose very stringent linearity requirements for the radio frequency power amplifier of the transmitter on which depends not a little the degradation of the modulated signal.
The power output from the final amplifier devices must be considerably lower than their saturation power so that the nonlinear distortions thereof introduced satisfy the specifications of the transmitter. These distortions are due to compression of gain at high power found in the trend of the Amplitude Modulation (AM/AM) distortion curve at high power and the amplitude modulation/phase modulation (AM/PM) conversion curve, again at high power.
Obviating these distortions usually involves oversizing these final amplifiers and hence high cost of the power amplifying section.
As known in itself, use of a linearizing network in the transmitting section permits use of power devices with lower saturation for a given distortion produced with a resulting increase of efficiency, e.g. for application in the transmitters of on-board repeaters in satellite communication systems or, for a given saturation power of final devices, such use also allows higher linearity of the amplifier, e.g. for applications in transmitters for earth stations in such satellite communication systems.
A linearization technique presently well known is termed "feed forward error control", and includes all the linearizers which use an auxiliary microwave amplifier which amplifies an error signal obtained by determining the difference between the input signal and the distorted one appropriately attenuated at the output from the main amplifier. The error signal is proportional to the distortions generated by the main amplifier so that, again added with appropriate phase and amplitude at the output of the main amplifier, this error signal reduces the distortions affecting the output signal.
It is clear that the merit figure or degree of quality of this linearization system depends almost exclusively on the balancing of the final adder or coupler which subtracts the error signal from the output signal of the amplifier. A balancing regulation circuitry (in amplitude and phase) of this coupler is therefore necessary and is quite complex. In addition, it is a true amplifier-linearizer complex in itself, not an addition to improve a known amplifier.
Another present linearization technique calls for the use of RF (radio frequency) predistorters, i.e. nonlinear networks inserted upstream of the final microwave amplifier, which distort the input signal by means of networks embodied with components which work in a nonlinear state in order to compensate for the AM/AM distortion curve and the amplitude/phase conversion curve AM/PM of the final power amplifier, and which guarantee better linearity of the transmitting section. The main drawback of these known predistorters consists, however, of the excessive complexity of said networks, and thus of their still excessive cost.
An example of a predistortion linearizer for microwave power amplifiers is described in Italian patent application No. 19497-A/87 filed by the same applicant Feb. 26, 1987, and incorporated herein.
In this previous Italian patent application there is described a predistortion linearizer applicable upstream of the power amplifier and which has a main network including a phase modulator and an amplitude modulator arranged in cascade. A secondary network with a base band frequency is provided. It includes means for amplitude detecting and filtering part of the input signal so as to produce a detected signal which is a function of the instantaneous input power. A pair of adjustable gain amplifiers are supplied with the detected signal and act on the modulators in such a manner as to give them nonlinear response curves, such as to compensate independently for both amplitude and phase nonlinearity of the power amplifier.
Such a linearizer, although it has all the advantages compared with the known art listed in the application, is still a costly and cumbersome embodiment, principally because of the presence therein of derived branches.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to overcome the above drawbacks and to provide a predistortion linearizer for microwave power amplifiers which is extremely simplified in its circuit structure. Indeed it comprises essentially a single transistor which carries out the functions both of the gain expander amplifier for recovery of the amplitude distortion of the power amplifier and as a generator of a command signal for a phase shift element for recovery of the phase distortion of the power amplifier. In a first form of the embodiment, this single transistor is placed upstream of the final power amplifier and is followed by the phase shift element. In a second form of the embodiment, its function is fulfilled by the same final power amplifier.
According to the invention, a first subpolarized transistor means provides gain expansion with increase in power of a signal at its input. A phase shifter means controlled by a continuous component of voltage present at an output of the first transistor means introduces a phase distortion for offsetting the phase distortion of the final power amplifier.
Further objects and advantages of the present invention will be made clear by the following detailed description of an embodiment thereof and the annexed drawings given for purely nonlimiting explanatory purposes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a circuit diagram of a first example of a realization of the linearizer which is an object of the present invention;
FIG. 1A shows a bipolar transistor which can replace the FET FT1 shown in FIG. 1;
FIGS. 2, 3, 4, and 5 show the trends of some characteristic parameters of the linearizer and final power amplifier as a function of the power Pi of the input signal;
FIG. 6 shows a first embodiment variation of the phase shift element D1 of FIG. 1;
FIG. 7 shows a second embodiment variation of the phase shift element, and
FIG. 7A shows a bipolar transistor which can replace the FET FT1 shown in FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a circuit embodiment of the linearizer which is an object of the invention and is applied upstream of a power amplifier for the purpose of compensating for the amplitude and phase distortions. Indeed, the amplitude and phase response curves of a microwave power amplifier are typically as shown in FIG. 2 wherein is shown the qualitative shape of the output power Pu (AM/AM distortion curve) and the input-output phase variation VF (AM/PM conversion curve) as a function of input power Pi. The linearizer thus has a dual purpose. First, it expands its own gain at the Pi values so that in FIG. 2 the knee of the curve Pu occurs to compensate for said knee and continue the linear shape of pu even in the immediate proximity of saturation. This latter zone is indicated by a horizontal shape which, however, cannot be offset. The second purpose is to vary its own input-output phase in a manner opposite to the shape of VF in FIG. 2.
In FIG. 1, RFin, RFout indicate the input and output connectors respectively of a radiofrequency signal.
C1, C2 . . . C5 indicate capacitances and L1, L2 inductances of a known type.
FT1 indicates a GaAsFET transistor (with gallium arsenide field effect) equipped as known with three connectors, namely a source S, drain D, and gate G1, used in a common source configuration.
R1 indicates a polarization resistance of FT1.
D1 indicates a varactor diode.
RA1, RA2, RA3 indicate common impedance matching networks for input, interstage, and output, respectively, and embodied, for example, in a microstrip.
VG, VP indicate the supply voltages of the gate of FT1 and of the anode of D1, and V+ indicates a fixed positive.
C1 and C2 are used as blocking capacitances of the continuous component at the input RFin and the output RFout, respectively. C4 and the networks C3-L2, C5-L1 form low-pass decoupling filters between the signal and the supplies VG, VP, and V+. C3, C4, and C5 have a grounded end.
The input signal is applied to the gate of FT1 through C1 and RA1. The voltage Vg is also applied to the gate of FT1 through the filter C3-L2. The source of FT1 is connected to ground, while the voltage V+ is brought to the drain through the filter C5-L1 and the resistance R1. The cathode of the diode D1 is also connected continuously to the drain of FT1 through the network RA2, and to the output RFout through the network RA3 and C2.
The transistor FT1 amplifies the RF signal applied at the input RFin. The values of fixed supply voltage V+, resistance R1, and voltage VG are chosen in such a manner as to keep FT1 in underpolarization conditions, i.e. with the working point near the pinch-off region (low values of drain-source current Ids and gate-source voltage Vgs).
In this manner an increase in the power of the Rf input signal is capable of changing the working point of the device, i.e. increasing the continuous component of the current Ids. Since the gain of FT1 depends on the continuous component of Ids, the increase of the latter causes an increase in gain and supplies the desired expansion effect.
FIG. 3 shows the qualitative shape of the gain curve Gi obtained as a function of the power Pi of the signal RF at the input RFin. By varying the parameters of the polarization network of FT1, i.e. VG, R1 and V+, it is possible to obtain a shape of Gi optimized from the point of view of compensation of the AM/AM distortion curve. The figures also show as a function of Pi the corresponding qualitative shape of the continuous component of Ids.
Due to the presence of the resistance R1, as the continuous component of Ids increases, the continuous component of the drain-source voltage Vds of FT1 decreases, and hence that of the polarization voltage VL of the varactor diode D1 (indeed D1 is connected continuously to the drain of FT1).
Thus, a detected voltage of the modulating signal proportional to the continuous component of Ids is localized and is used as a control signal of the phase variation introduced by the downstream device which, in the nonlimiting example described, is the varactor diode D1.
The effect obtained is thus a modulation of the voltage VL which, as is known, influences the internal capacitance value of the varactor and hence the phase shift introduced therefrom onto the RF signal. This effect can be used with advantage to offset the conversion curve AM/PM.
FIG. 4 shows the qualitative shape of the phase variation FL as a function of the power Pi of the input signal. The shape of FL can be made specular in relation to that of VF (shown with broken line in FIG. 4) by appropriate sizing of the parameters which influence it, i.e. R1 and VP.
To sum up, the transistor FT1 fulfills a dual function: that of gain expander to offset the AM/AM distortion curve and that of detector of a modulation voltage which directly pilots a phase shifter to offset the AM/PM conversion curve.
More specifically, the gain expansion characteristic is adjusted by varying VG, and the phase characteristic is adjusted by varying VP.
The device of FIG. 1 follows very rapidly the dynamics of the input signal RF, i.e. its response as a gain expander and phase shifter is a wide band for the modulating signal because it consists of a signal RF branch. This is in effect very important because it makes the device usable even when the multicarrier modulating signal is wide band, e.g. in transponders for satellites.
In addition, there is an undoubted advantage in terms of size and cost reduction of the components of the linearizer which can be embodied with microstrip or Microwave Integrated Circuit (MIC) technology using both discrete packaged components and chip-and-wire or integrated in Monolithic MIC (MMIC) technology.
Numerous variations on the embodiment described as an example in FIG. 1 are possible, without going beyond the scope of the innovative principles contained in the invention concepts herein.
The linearization function can be performed by the final power stage comprised, for example, of a transistor of the FT1 type of FIG. 1, brought to a similar working condition.
This may be explained by a digital example also with reference to FIG. 5 which shows the shapes of the output power Pu of the final power stage in two working conditions, normal (Ids=2A) and modified in accordance with the invention (Ids-0.7A), respectively, and which also shows the shape of the continuous component Ids of the drain current of the transistor of the final stage, as a function of the input power Pi.
Assume a final power stage comprised of a GaAsFET transistor which in linear conditions has a gain of 10 dB with a working point of Fds=10 V, Ids=2A, and an output saturation power Pusat=40 dBm at modulated signal frequencies of approximately 6-7 GHz. Under these conditions, the shape of output power Pu as a function of input power Pi is as indicated in FIG. 5 by parameter Ids=2A, with the knee zone to be linearized.
If we now decrease the gate-source voltage Vgs of the transistor to obtain Ids=0.7A, the gain of the linear zone decreases to approximately 7 dB. Under these conditions when the input power Pi increases, Ids also tends to increase to a nominal value of 2A in conformity with the shape of Ids shown in the figure. The increase of Ids causes an increase in the gain Gi of the transistor just in the zone where the curve Pu(Ids=2A) had the knee, introducing in this case a self-linearization effect: the amplitude in the knee zone of the curve Pu(Ids=0.7A) decreases greatly, offsetting the distortion curve AM/AM.
As concerns offsetting the conversion curve AM/PM, the phase variations can be offset by a circuit of known type upstream and which is piloted by the voltage Vds of the final transistor as described with reference to FIG. 1.
The variation now described can be used to advantage in QAM multi-level modulation systems where the RF output power is not constant, but varies considerably in relation to the average value depending on the point of the constellation of symbols to be transmitted. For example, in the 64QAM system there is a difference of approximately 8 dB between average and maximum RF output power. There is a considerable current savings; for the low levels of the constellation for which the output power Pu is low, the current Ids stays around 0.7A and reaches 2A only for the higher levels for which Pu is high. Since the points of the constellation are all equally probable, the average Ids current will be approximately 1.1-1.2A, and not 2A, with a clear consumption savings. A decrease of gain in the linear zone from 10 to 7 dB does not involve problems because the 3 dB difference is necessary only at the power peaks.
A second variation calls for the embodiment of the phase shifter as in FIG. 6, wherein the same symbols as in FIG. 1 indicate the same components interconnected in the same manner.
In FIG. 6 there has been added a second varicap diode D2 equal and antiparallel to D1 for the signals. The anode of D2 is connected to the cathode of D1, while the cathode of D2 is polarized by the direct voltage VP2 and is connected to ground for the signals through the filter capacitance C6.
The embodiment of FIG. 6 serves, in case it is desired, to offset a phase variation which may be either leading or delaying. One diode offsets the delaying phase variations and the other the leading ones. By appropriately sizing the voltages VP and VP2, it is possible to make one of the two diodes work while excluding the other, thus obtaining a leading phase shift with D2 inserted, or delaying with D1 inserted.
A third variation calls for an embodiment of the phase shifter as in FIG. 7 wherein the same symbols as in FIG. 1 indicate the same components interconnected in the same manner and performing the same functions.
In FIG. 7 the phase shifter is embodied by a GaAsFET transistor indicated by FT2, and is polarized in such a manner as to function as a normal amplifier in a common source configuration with the continuous component of the drain-source current Ids2=1/2Idss. The latter is the maximum value of the drain current for Vgs=0.
R2 indicates the load resistance of FT2.
C7, C8, and C9 indicate capacitances and L3, L4 indicate inductances of known type. C9 and the networks C7-L3, C8-L4 form low-pass decoupling filters between signals and supplies for output RFout, gate FT2, and drain FT2; C7, C8 and C9 have one end grounded.
RA4 indicates an output matching network with the same function as RA1, RA2, and RA3.
By varying the continuous component of the gate-source voltage of FT2, there is obtained a variation of the continuous component of the drain current Ids. This does not cause an appreciable variation in the gain of FT2, since FT2 is in a linear operation condition, but does vary the value of gate-source capacitance Cgs of FT2. The effect obtained is equivalent to that supplied by the varactor diode D1 of FIG. 1, i.e. variation of the phase FL of the output signal RFout which offsets the AM/PM conversion curve (see FIG. 4).
In this case also the voltage detected in the modulation of the modulating signal (which is proportional to the continuous component of Ids of FT1 located at the ends of R1) is used as the control signal of the phase variation introduced by FT2. To bring this control signal to FT2, it is necessary to continuously pair the two transistors FT1 and FT2, bringing to the input of FT2 the voltage taken from R1 either in phase or in phase inverted fashion, depending on whether the phase variation desired is leading or delaying, respectively.
To introduce a phase delay there can be used the component indicated by AMP in FIG. 7, which is a continuous inverting amplifier with variable gain and a pass band having a width at least double that of the modulating input signal band. AMP receives and amplifies the continuous component of the drain voltage of FT1 at one end of R1, and supplies it with a changed sign to the gate of FT2 through the filter C7-L3 to obtain a modulation effect of the continuous component of the gate voltage of FT2. This effect is translated into a variation of the capacitance Cgs of FT2.
AMP can be embodied by a reversing stage of any known type. If embodied by a GaAsFET transistor, the entire circuit of FIG. 7 can be integrated in MMIC technology in a simple and economical embodiment.
If FT2 is not to lead but is to delay in phase, the amplifier AMP will have the same characteristics as above, except that it will not be reversing.
As another variation, the transistors called for in the various forms of embodiment described can also be of another type, e.g. bipolar.
This is shown in FIGS. 1A and 7A, wherein the bipolar transistors replace the FET FT1.
Although various minor changes and modifications might be proposed by those skilled in the art, it will be understood that we wish to include within the claims of the patent warranted hereon all such changes and modifications as reasonably come within our contribution to the art. | A predistortion linearizer for microwave power amplifiers wherein a single transistor, e.g. of the GaAsFET type, is subpolarized near the pinch-off condition, and carries out the functions both of a gain expander amplifier for recovery of amplitude distortion of the power amplifier and as a command signal generator for a dephaser element for recovery of the phase distortion of the power amplifier. | 7 |
BACKGROUND OF THE INVENTION
The invention is based on an apparatus having a control motor for intervention into a transmission device between an operating element and a control device that determines the output of a driving engine.
Various regulating operations for driving engines require an intervention into the transmission device between the operating element, such as a gas pedal, and the control device, such as a throttle valve in an Otto engine or an adjusting lever in a Diesel engine or the like. The regulation may be effected by regulating devices known per se, for instance to avoid slip between vehicle wheels driven by the engine and a road surface.
In a known apparatus of this type, the operating element is operatively connected to a first lever, for instance via a cable, and the control device is operatively connected to a second lever, for instance via a further cable. A restoring spring tends to urge the control device into a terminal position. A tension spring acts on the one hand on the first lever and on the other on the second lever, tending to press a stop of the first lever against a stop of the second lever. The effect of the tension spring is greater than the effect of the restoring spring. A control motor may also act upon the second lever, such that the second lever is rotated relative to the first lever, counter to the tension spring, and can thus move the two stops away from one another. On the rotation of the second lever relative to the first lever, the position of the control device can be varied relative to the position of the operating element. The control motor acts upon the second lever in the direction of the restoring spring, counter to the tension spring.
A distinction can be made between two operating states of the transmission device: an unregulated operating state, and a regulated state.
In the unregulated operating state, the control motor is not triggered. A particular position of the control device is associated with a particular position of the operating element. The control device follows the operating element in accordance with a predetermined transmission ratio.
In the regulated operating state, the transmission ratio is varied by the control motor. First, the operating element specifies a position. This position would be equivalent to a particular position of the control device in the unregulated operating state. In the regulated operating state, however, the control motor is triggered, which has the effect that the control device assumes a position different from the position in the unregulated operating state.
In the unregulated operating state, that is, when the control motor is not triggered, a rotor of the control motor must be jointly actuated when the operating element is actuated, in order to change the position of the control device. This requires greater actuating forces upon actuation of the control device. To avoid having to design a restoring spring with an overly great force, a proposal has been made that a free-wheel be installed between the control motor and the second lever. However, the free-wheel can lower the actuating forces in only one actuation direction.
OBJECT AND SUMMARY OF THE INVENTION
The apparatus according to the invention has an advantage over the prior art that by introducing a third rotary element between the second rotary element and the rotor of the control motor, no increased actuating forces are brought about in the unregulated operating state upon actuation of the operating element by the apparatus. Because of the third rotary element, it is possible upon actuation of the operating element to adjust the control device without having to move the rotor of the control motor along with it.
Modifications of and improvements to the apparatus are defined herein. In particular, at least the following advantages are attained:
Disposing all three rotary elements coaxially on one shaft results in a particularly simple, compact construction.
The apparatus may be embodied such that via the third rotary element, the second rotary element is rotatable by the control motor in a direction of reduced and/or in the direction of increased output of the driving engine.
The rotation by the control motor in the direction of increased output can be limited to a maximum allowable angle of rotation beta (β), and the rotation in the direction of lesser output of the driving engine can likewise be limited to a maximum allowable angle of rotation gamma (γ).
By providing the second rotary element with an eccentrically disposed knob protruding axially from it and by providing the third rotary element with a recess that can be engaged by the knob, with the length of the recess in the circumferential direction being greater than the length of the knob, again in the circumferential direction, the second rotary element can be rotated freely relative to the third rotary element by the amount by which the circumferential length of the recess exceeds that of the knob.
When the control motor is not being triggered, a reverse torsion spring means can move the third rotary element into a position of repose. The position of repose of the third rotary element may be selected such that given sufficient play between the knob and the recess in the third rotary element, the control device can be adjusted from a position of minimal output of the driving engine to a position of maximum output of the driving engine, without having to move the third rotary element and hence the rotor of the control motor along as well.
A gear can advantageously be disposed between the third rotary element and the control motor. The reverse torsion spring means may comprise a spring one end of which can act directly upon the third rotary element. This requires a spring with only relatively short spring travel. On the other hand, it is also possible for the reverse torsion spring means to comprise at least one spring that acts indirectly upon the third rotary element via the gear. In conventional control motors, the gear typically must be embodied such that a high rotor rpm corresponds to a low rpm of the third rotary element. Stepping down from high rpm to low rpm, however, simultaneously means a step up from a low torque to a high torque. It is therefore also possible to use an indirectly acting spring of only relatively low force or low torque.
Embodying the reverse torsion spring as a spring subjected to bending or a flat band spring subjected to bending results in a particularly favorable construction. The spring may be wound approximately in a circular arc, or may have the form of a spiral spring. This allows the reverse torsion spring to be disposed particularly favorably and space-savingly, coaxially with the third rotary element or coaxially with a drive wheel of the gear.
The control motor, the gear and the shaft for the rotary elements may be disposed on a common base plate. A particularly favorable construction is obtained if the control motor is joined to the base plate such that a drive wheel connected to the rotor protrudes variably far into a recess in the base plate or through to the other side of the base plate, where it can drive the drive wheels of a gear. The shaft for the rotary elements is likewise joined to the base plate, on the side remote from the control motor.
Usually, the transmission device between the operating element and the control device substantially comprises a Bowden cable. For introducing the apparatus according to the invention, the Bowden cable can be severed at virtually any arbitrary point. The operating element can then be operatively connected to the first rotary element via a first Bowden cable and the second rotary element can be operatively connected to the control device via a second Bowden cable. The fixation points for a Bowden cable sheath can also be secured to the base plate.
One or more fastening holes can be provided in the base plate, and as a result the entire apparatus can be secured to a chassis, e.g. to the body in the case of a motor vehicle. The selection of where to install the apparatus is relatively flexible. It is then possible to attach the apparatus where there is little vibration; in that case a relatively simple, inexpensive electric motor can be used as the control motor.
The entire apparatus can be protectively encased in a housing having only a few recesses. The connection between the operating element and the first rotary element is effected through one of the recesses; the connection betweeen the second rotary element and the control device is effected through another; and the lines for triggering the control motor are ducted through a third recess. The apparatus is fastened to the chassis through a further recess or recesses. However, the housing may also be in two parts. One part of the housing, for instance, may cover the control motor on one side of the base plate, and another part of the housing may cover the rotary elements and the gear.
The tension spring that acts on both the first rotary element and the second rotary element is advantageously embodied as a spring subjected to bending. It is particularly favorable for the tension spring to be embodied as a flat-band spring subjected to bending and to be wound in the form of a spiral spring. This makes it possible to dispose the tension spring approximately coaxially with and between the first and second rotary elements.
Particularly advantageous regulation is attained if the position of the control device can be detected with the aid of a travel measuring system.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of preferred embodiments taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 show a first exemplary embodiment of the invention in an exploded view from two different angles;
FIG. 3 shows a detail of the spring connection of the first exemplary embodiment; and
FIGS. 4 and 5 show a second exemplary embodiment, again in an exploded view.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The structure and mode of operation of an apparatus embodied in accordance with the invention, having a control motor for intervention into a motion transmission device 1, 66 between an operating element 3 and a control device 6 (FIG. 2) that determines the output of a driving engine will now be described in detail in terms of two exemplary embodiments, referring to FIGS. 1-5.
FIGS. 1 and 2 show the first exemplary embodiment, and FIGS. 4 and 5 show the second exemplary embodiment, in each case from different angles. For the sake of easier comprehension of the drawings, the distances between individual components of the apparatus have been exaggerated; the parts have been shown in spaced relationship. FIGS. 1, 2, 4 and 5 are so-called exploded views. In all the drawing figures, identical or identically functioning parts have been identified by the same reference numerals. To make the association of the various components with one another clearer, existing axes and shafts have been shown extended with dashed lines.
From the operating element 3 (FIGS. 2 and 5), embodied for instance as a gas pedal, a first part 1 of the transmission device leads to a first rotary element 2. In both exemplary embodiments shown, the first part 1 of the transmission device comprises a Bowden cable, with a Bowden cable sheath 4 and a Bowden cable core 5. Of the sheath 4, only a portion adjoining the apparatus has been shown. The portion of the sheath 4 adjoining the apparatus is fixed to a first retaining means 7. The first rotary element 2 substantially comprises a disk 9 having an outer circumference 10; with a radial groove 11 cut into the outer circumference 10; a central through bore 12, an eccentric bore 15 intersecting the groove 11 in the vicinity of the outer circumference 10; a cylindrical, axially protruding spring guide element 16 having a face end 17 remote from the disk 9; a protrusion 18 having a stop 19 protuding axially from the disk 9 on the same side as the spring guide element 16 and located in the vicinity of the outer circumference 10; and an axial recess 21 in the disk 9 that is likewise provided on the same side as that of the spring guide element. A plurality of radial slits 23 are provided in the spring guide element 16. The Bowden cable sheath 4 of the first part 1 of the transmission device ends in the vicinity of the first retaining means 7. The Bowden cable core 5 protrudes from the sheath 4 resting in the groove 11 and wraps partway around the disk 9. One end of the core 5 is connected to a bolt 24 that is placed in the eccentric bore 15.
A second rotary element 30 is supported coaxially with the first rotary element 2. The second rotary element 30 essentially has the following segments: a disk 31 having an outer circumference portion 32 with an axial groove 34 provided in the outer circumference portion 32; the outer circumference portion is narrower than the main body of the disk 31 which is formed with surface faces 36 and 37 on opposite sides of the outer circumference portion 32; face 36 is oriented toward the first rotary element 2; and the face 37 is opposite face 36 the face remote from the first rotary element; an axial recess 39 is formed in the second rotary element 30 from the side including face 36; the rotary element 30 includes a central through bore 40, and an eccentric bore 44 in the vicinity of the outer circumference 32. The though bore 40 is divided into an axial region 41 of somewhat smaller diameter and an axial region 42 of somewhat larger diameter. A step 43 divides the bore 40 into a first and second region 56 and 57. The faces 36 and 37 are not rotationally symmetrical, that is they are not completely cylindrical; instead, face 36 has a bulging part 45 with a stop 46 and a knob 48 protrudes from the face 37. A slit 49 is provided in the knob 48 in which an elastomer molded element 50 is placed. The elastomeric molded element 40 protrudes in the rotational direction past the knob 48 on two sides and on each side forms a respective stop face 51 and 52. The axial recess cut 39 is also not rotationally symmetrical on its outer circumference but instead has an additional radial recess 54 extending variably into the bulging part 45 on the face 36. Located inside the axial recess 39, centrally to the through bore 40, is a guide element 55, which is connected to the disk 31 and is stepped on its outer circumference. The guide element 55 includes the first outer diameter region 57, beginning at the disk 31, and the smaller second outer diameter 58. Between the two outer diameters 57 and 58 is a step 59. A bolt 62 is placed in the eccentric bore 44. One end of a Bowden cable core 64 of a second part 66 of the transmission device is secured on the bolt 62. Part of the core 64 is located in the groove 34 and wraps partway around the outer circumference portion 32 of disk 31 of the second rotary element 30. From the second rotary element 30, the core 64 leads to a Bowden cable sheath 69 connected to a second retaining means 68. The core 64 and sheath 69, as a component of the second part 66 of the transmission device, lead to the control device 6, embodied for instance as a throttle valve, which is for instance disposed in the air intake tube 70 of an internal combustion engine, not shown.
A tension spring 72 in the form of a spiral is located between the first rotary element 2 and the second rotary element 30. It is located partly inside the axial recess of the second rotary element 30 and partly inside the axial recess 21 in the first rotary element 2. A first folded-over end 74 on the inner spiral of the tension spring 72 is inserted into one of the radial slits 23 of the spring guide element 16 on the first rotary element 2. A second folded-over end 75 on the outer spiral of the tension spring 72 engages the recess 54 in the bulging part 45 of the second rotary element 30. The second outer diameter 58 on the guide element 55 of the second rotary element 30 is somewhat smaller than the central through bore 12 of the first rotary element 2, and the first outer diameter 57 is markedly larger than the central through bore 12. The guide element 55 can therefore be thrust some distance into the through bore 12 of the first rotary element, until the face end 17 of the spring guide element 16 comes to rest on the step 59 of the guide element 55.
On the side of the second rotary element 30 remote from the first rotary element 2, a third substantially semi-circular rotary element 80 is disposed concentrically to the two rotary elements 2 and 30. The third rotary element has a center bore 81. A guide bushing 82 is seated in the center bore 81. The guide bushing 82 protrudes variably far out of the side of the third rotary element 80 oriented toward the second rotary element 30. The guide bushing 82 has an outer diameter 84, a center bore 85 and a face end 86. The third rotary element 80 also has a substantially semicircular partial ring 87 on its outside. Two spokes 89 and 90 extend inward from the partial ring 87 and merge with one another, encompassing the center bore 81. A tooth profile 92 extends over the circumference of the partial ring 87. The partial ring 87 extends over only a part of the outer circumference of the third rotary element 80. A recess 94 is formed inside the third rotary element 80, between the partial ring 87 and the two spokes 89 and 90. A bearing face 96 is formed on the spoke 89, oriented toward the recess 94. A bearing face 97 is formed on the spoke 90, likewise oriented toward the recess 94. A boltlike attachment 101 protrudes axially from the spoke 89 and a further boltlike attachment 102 protrudes axially from the spoke 90 on the third rotary element 80, on a side remote from the second rotary element 30. The part of the guide bushing 82 protruding from the third rotary element 80 on the side oriented toward the second rotary element 30 fits with slight play into the region 42 of the through bore 40, until the face end 86 comes to rest on the step 43 of the second rotary element 30.
The third rotary element 80 is supported on a shaft 110. The second rotary element 30 is also supported, together with the first rotary element 2, on the shaft 110. The shaft 110 is somewhat longer than the assembly comprising the first rotary element 2, the second rotary element 30 and the third rotary element 80. The shaft 110 has a first end 111, and a second end 112. The first end protrudes past the assembly comprising the three rotary elements on the side where the first rotary element 2 is located. The first end 111 has an annular groove 115, into which a retaining ring 117 can be snapped. The second end 112 of the shaft 110 is firmly joined in a bore 119 to a base plate 120.
The base plate 120 has a first side 124 and a second side 125. The first side 124 faces the rotary elements 2, 30 and 80, and the second side 125 is located on the opposite side of the base plate 120 from the first side 124.
A control motor 130 is disposed on the second side 125 of the base plate 120. Fastening elements such as screws for securing the control motor 130 to the base plate 120 are not shown in the drawing for the sake of simplicity. A rotor 132 protrudes from the face end of the control motor 130 oriented toward the base plate 120 and into a connecting bore 134. Since the rotor 132 is partly covered by either the base plate 120 or the control motor 130, only a stub of the rotor 132 is visible (FIGS. 2 and 5). A first drive wheel 131 of a gear is mounted on the rotor. For the sake of clarity, the first drive wheel 131 is shown in FIGS. 1, 2, 4 and 5 spaced apart from the control motor 130; in actuality, it is joined to the rotor 132 of the control motor 130. The connecting bore 134 is located in the base plate 120 between the first side 124 and the second side 125. The diameter of the connecting bore 23 in the first rotary element 2 is greater than an outer diameter of the first drive wheel 131 and is provided such that when the control motor 130 is fastened to the base plate 120, the first drive wheel 131 secured to the rotor 132 can be inserted into the connecting bore 134 of the base plate 120. The first drive wheel 131 protrudes variably far from the first side 124 of the base plate 120.
A stub 136, with a bore 137 in its center, is located on the first side 124 of the base plate 120. A notch 139 is provided along a jacket line of the stub 136. In the bore 137, a second shaft 140 is firmly connected to the stub 136 and thus to the base plate 120. A plate wheel 142 (FIGS. 1, 2 and 3) and a second drive wheel 144 are both rotatably supported on the second shaft 140. In the second exemplary embodiment (FIGS. 4 and 5), the plate wheel 142 is omitted and formed as a portion of the second drive wheel 144. The second shaft 140 protrudes through a central bore 145 in the plate wheel 142 and through a bore control 147 in the second drive wheel 144 and out of the second drive wheel 144 with one end 148, remote from the bore 137 in the base plate 120. On the end 148 of the second shaft 140 protruding past the second drive wheel 144, an annular groove 149 is provided. A retaining ring 151 can be snapped into the annular groove 149. The retaining ring 151 prevents the second drive wheel 144 and plate wheel 142 from sliding down off the second shaft 140. A first reverse torsion spring 155 is located between the plate wheel 142 and the first side 124 of the base plate 120. The reverse torsion spring 155 is a spring subjected to bending and takes the form of a spiral spring. The reverse torsion spring 155 surrounds the stub 136. An inner or first end 156 of the reverse torsion spring 155 engages the notch 139 of the stub 136. An outer or second end 157 of the reverse torsion spring 155 is pivotably connected to the plate wheel 142 (FIGS. 1, 2 and 3) or to the second drive wheel 144 (FIGS. 4 and 5). A polygonal first dog 165 protrudes radially outward from and beyond a cylindrical rim 162 of the plate wheel 142 (FIGS. 1 and 2). The dog 165 has a first stop end 167 and a second stop end 168, seen in the circumferential direction. The second drive wheel 144 substantially comprises a first disk portion 169 and a second disk portion 170. A first stop edge 171 and a second stop edge 172 (FIGS. 1 and 2) are provided on a side of the first disk portion 169 of the second drive wheel 144 toward the plate wheel 142. The two stop edges 171, 172 are embodied on a collar 174, axially engaging the outside of the plate wheel 142, and are disposed such that on a rotation of the second drive wheel 144, depending on the direction of rotation, either the first stop edge 171 comes to rest on the first stop end 167 of the plate wheel 142, or the second stop edge 172 comes to rest on the second stop end 168. In the second exemplary embodiment (FIGS. 4 and 5), the two stop edges 171, 172 are unnecessary and so are not provided. The first disk portion 169 has a larger diameter than the second disk portion 170. The first disk portion 169 and the second disk portion 170 are each provided with a toothed profile 173 on the outer circumference. A toothed profile of the first drive wheel 131 meshes with the toothed profile of the first disk portion 169 of the second drive wheel 144, and a toothed profile of the second disk portion 170 of the second drive wheel 144 meshes with the toothed profile on the partial ring 87 of the second rotary element 80.
A second dog 190 also protrudes radially from and beyond the cylindrical rim 162 of the plate wheel 142. Respective recesses 191 and 192 (FIGS. 1, 2 and 3) are provided in the cylindrical rim 162, on either side of the second dog 190 as seen in the circumferential direction.
In the first exemplary embodiment (FIGS. 1 and 2, a second reverse torsion spring is shown at 175. The second reverse torsion spring 175 is a spring subjected to bending and has the shape of a flat-strip spring curved in an arc. The reverse torsion spring 175 has two ends. The first spring end 177 is bent at an angle and is joined to the base plate 120 with the aid of a seat 178 and a screw 179. A stop plate 182 is integrated with the seat 178. Depending on the position of the third rotary element 80, the second spring end 180 can either rest on a stop 184 protruding from the first side 124 of the base plate 120 or it can come to rest on the bolt 102 of the third rotary element 80. The second reverse torsion spring 175 is absent in FIGS. 4 and 5.
In the first exemplary embodiment (FIG. 1-3), the two reverse torsion springs 155 and 175 form a reverse torsion spring means. In the second exemplary embodiment (FIGS. 4 and 5), the reverse torsion spring means is embodied by the first reverse torsion spring 155 alone.
The second exemplary embodiment (FIGS. 4 and 5) includes fewer parts than the first exemplary embodiment (FIGS. 1, 2 and 3). Among others, the details to be described below, identified by reference numerals 193-234, are found only in the first exemplary embodiment (FIGS. 1-3). FIG. 3 therefore applies only to the first exemplary embodiment.
In the first exemplary embodiment (FIGS. 1-3), a third bore 193 having an internal thread is located in the base plate 120, on the first side 124. A screw 194 having a head 195 and a shaft 197 is screwed into the third bore 193. A washer 199 and a sheath 204 are disposed between the screw head 195 and the base plate 120. The diameter of a hole in the washer 199 and the diameter of a hole in the sheath 204 are somewhat larger than the diameter of the screw shaft 197, so that this shaft can be passed through the washer 199 and sheath 204. The length of the shaft 197, the thickness of the washer 199, the length of the sheath 204 and the depth of the bore 193 having the thread are matched to one another in such a way that the screw 194 can be screwed far enough into the third bore 193 that the washer 199 and sheath 204 are firmly fastened between the screw head 195 and the base plate 120. The washer 199 and the sheath 204 are disposed on the screw shaft 197 such that the washer 199 rests on the screw head 195 and the sheath 204 rests on the base plate 120. The sheath 204 has an outer diameter 206. The outer diameter 206 is somewhat smaller than the diameter of a hole 208 in a star wheel 210. The star wheel 210 is located between the washer 199 and the base plate 120 and surrounds the sheath 204. Since the star wheel 210 is not as long as the sheath 204, the star wheel 210 can rotate freely even when the screw 194 is firmly tightened.
The plate wheel 142 with the second dog 190 and the star wheel 210 have a special appearance, adapted to one another, which will now be described in greater detail referring to FIG. 3. FIG. 3 shows a section transversely through the cylindrical rim 162 of the plate wheel 142, such that the section also extends through the second dog 190 and through the two recesses 191 and 192. Also shown in section are the stub 136 with the bore 137 and the notch 139 as well as the second shaft 140. FIG. 3 is a view vertically on a portion of the first side 124 of the base plate 120, onto the reverse torsion spring 155, the star wheel 210, the washer 199 and the screw head 195, as well as on the above-described section through the plate wheel 142. The plate wheel 142 has a circumference 215 and the star wheel 210 has a circumference 216 that is interrupted in a suitable manner. The plate wheel 142 has an axis of rotation 218 and the star wheel 210 has an axis of rotation 219. The distance between the axis of rotation 218 and the axis of rotation 219 is shorter than the sum of the radius of the circumference 215 plus the radius of the circumference 216. The plate wheel 142 and the star wheel 210 cooperate in a similar manner to a so-called single-tooth or Maltese cross gear known per se, and therefore its function will be described only briefly here. The star wheel 210 can assume only a position in which the cylindrical rim 162 of the plate wheel 142 can assume at least some distance into a first indentation 222 or into a second indentation 223 of the star wheel 210, and with each rotation of the plate wheel 142, the second dog 190 comes to mesh with the first notch 226 or the second notch 227 of the star wheel 210, depending on the rotational direction. The first notch 226 is delimited from the first indentation 222 by a point 231 and from the circumference 216 by an edge 232. The second notch 227 is delimited from the two indentations 222 and 223 by points 233 and 234. To enable the second dog 190 to enter into engagement with one of the notches 226 or 227 upon a rotation of the plate wheel 142, the edge 232 and the points 231, 233 and 234 must be capable of extending into one of the recesses 191 or 192.
The control motor 130 flanged to the second side 125 of the base plate 120 is covered with a hood 252. Located in the hood is an aperture 254, through which electrical lines, not shown, for supplying energy to and triggering the control motor 130 can be ducted. The parts of the apparatus disposed on the first side 124 can also be covered, with a second hood 256. The hood 256 is indicated in FIGS. 1 and 2 only by dot-dash lines, for the sake of clarity. The hood 256 has two recesses 257, only one of which is shown in FIGS. 4 and 5. The first part 1 of the transmission device is passed through the first recess 257, and the second part 66 of the transmission device is passed through the second recess 257. Located between the hood 252 and the hood 256 is the base plate 120, from which two corners 258 and 259 extend laterally past the hoods 252 and 256. One aperture each 261 and 262 is located in the corners 358 and 259. With these apertures 261 and 262, the base plate 120 and hence the entire apparatus can be secured, for instance with screws, not shown, to an arbitrary chassis, also not shown, such as a vehicle body.
Experiments have shown that the outcome of the intervention into the transmission device is better if the position of the control device 6 can be detected with a travel measurng system 265, such as a potentiometer. Measurement signals originating in the travel measuring system 265 can then be processed by a suitable electronic control unit, along with further set-point variables, to make control signals with which the control motor 130 is triggered.
In the apparatus having the transmission device 1, 66, a distinction can be made, as described above, between two operating states: an unregulated operating state and a regulated operating state.
In the unregulated operating state, the control motor 130 is not triggered. Because of the reverse torsion spring means, the third rotary element 80 is in a position of repose. The position of the third rotary element 80 can be defined structurally by providing that the first rotary element 2 and the second rotary element 30 can be rotated into any desired position, without one of the stop faces 51 and 52 of the second rotary element 30 coming to rest on one of the bearing faces 96 and 97 of the third rotary element 80. Thus, the first two rotary elements 2 and 30 can be rotated without having to rotate the rotor 132 of the control motor 130.
Pivotably connected to the first part 1 of the transmission device, in this exemplary embodiment the Bowden cable, are the operating element 3, on one end, and as described the first rotary element 2, on the other. Pivotably connected to the second part 66 of the transmission device are the second rotary element 30 on one side, as described above, and the control device 6, on the other. With the tension spring 72, the first end 74 of which can act upon the first rotary element 2 and the second end 75 of which can act upon the second rotary element 30, the stop 19 of the first rotary element 2 is pressed in the direction toward the stop 46 of the second rotary element 30. The tension spring 72 is installed with initial tension between the two rotary elements 2 and 30. Basically, it would suffice for a single radial slit 23 to be provided in the first rotary element 2 to receive the first end 74 of the tension spring 72. By providing a plurality of slits 23 in the first rotary element 2, however, the initial tension of the tension spring 72 can be adjusted in relatively small stages.
The first rotary element 2 is guided in the axial and radial directions by the guide element 55 having the two outer diameters 57 and 58 and having the step 59 and by the central through bore 12 in the first rotary element 2. However, the through bore 40 of the second rotary element 30 may also be embodied somewhat larger, so that a bushing can be inserted into it, onto which the first rotary element 2 and the second rotary element 30 are then mutually guided. By the initial tension of the spring 72 and the mutual guidance of the first rotary element 2 and second rotary element 30, these two rotary elements together with the tension spring 72 form a compact unit that is easy to install.
The first rotary element 2 is moved via the first part 1 of the transmission device. In the unregulated operating state, a movement of the first rotary element 2 is transmitted directly to the second rotary element 30, and its movement in turn is transmitted via the second part 66 of the transmission device to the control device 6. An adjustment of the operating element 3 and hence of the Bowden cable core 5 in a direction represented by an arrow 269 effects an identical adjustment of the Bowden cable core 64 and hence of the control device 6 in the direction represented by a further arrow 270. If the operating element 3 is adjusted in the direction counter to the arrow 269, the situation is comparable. There is a unique relationship between one position of the operating element 3 and one position of the control device 6.
In self-propelled machines, such as passenger cars, it is typically not possible to transmit both tensile and compressive forces with the transmission device. If that is the case, then a force of a restoring spring 266, disposed for instance on the control device 6, must be capable of returning the control device 6 to an initial position. With an operating force engaging the operating element 3, the control device 6 is then moved variably far away from its initial position by means of the transmission device. The restoring spring 266, however, acts upon the second rotary element 30 as well, counter to the tension spring 72. Since in the unregulated state the second rotary element 30 must not be allowed to execute any motion relative to the first rotary element 2, the force of the tension spring 72 must be greater than the force of the restoring spring 266, and frictional forces in the transmission device must be taken into account in this connection as well. If tensile and compressive forces can be transmitted with the transmission device, as is sometimes the case with stationary engines, then the restoring spring 266 can optionally be dispensed with and the tension spring 72 can be made weaker.
To reduce the weight and/or to enable simple installation and/or observation of the tension spring, recesses, not shown in the drawing, may be provided in the disk 9 of the first rotary element 2 and/or in the disk 31 of the second rotary element 30.
The third rotary element 80 is guided in the axial and radial directions with the aid of the guide bushing 82 in the central through bore 40 of the second rotary element, in the region having the greater diameter 42 and the step 43. This makes the third rotary element 80 easy to install, along with the second rotary element 30 and the first rotary element 2, on the first shaft 110 firmly connected to the base plate 120. However, the rotary elements 2, 30, 80 may instead be embodied in such a way that they are guided solely and directly on the first shaft 110.
The knob 48 on the second rotary element 30 having the elastomeric molded part 50 with the stop faces 51 and 52 protrudes into the recess 94 of the third rotary element 80. The recess 94 must provide enough room so that on the adjustment of the two rotary elements 2 and 30 from a desired rotated position to a second rotated position, the stop faces 51 and 52 of the second rotary element 30 do not come to rest on the bearing faces 96 and 97, if the third rotary element 80 is in its position of repose. In the unregulated operating state, this makes an adjustment of the control device 6 by means of the operating element 3 possible entirely without the influence of the control motor 130.
Instead of providing the knob 48 on the second rotary element 30, the knob 48 can also be provided on the third rotary element 80 and the recess 94 can be provided on the second rotary element 30.
The knob 48 having the stop faces 51, 52 of the second rotary element 30, together with the recess 94 and the bearing faces 96, 97 of the third rotary element 80, forms a coupling. In the regulated operating state, one of the stop faces 51, 52 comes to rest on one of the bearing faces 96, 97; that is, the coupling is operative. In the unregulated operating state, the stop faces 51, 52 can move away from the bearing faces 96, 97; that is, the coupling is inoperative. Accordingly, there is a coupling 48, 51, 52, 94, 96, 97 existing between the second and third rotary elements 30 and 80, that is not operative in certain positions of these rotary elements 30, 80 relative to one another.
If the diameter of the groove 11 of the first rotary element 2 is equal to that of the groove cut 34 of the second rotary element 30, then in the unregulated operating state, upon adjustment of the Bowden cable core 5 of the first part 1 of the transmission device by a certain amount, the Bowden cable core 64 of the second part 66 of the transmission device adjusts by precisely the same amount. On the other hand, if the two diameters differ, then the transmission of an adjustment of the core 5 to the core 64 is either reinforced or diminished. The grooves 11 and 34 of the two rotary elements 2 and 30 need not necessarily be circular, nor need they be necessarily centered with respect to the through bores 12 and 40. If at least one of the grooves 11, 34 is not central to the corresponding through bore 12, 40 and/or if one of the grooves is in the form of a cam, for example, then the transmission ratio between the first part 1 and the second part 66 of the transmission device can be defined arbitrarily within wide limits as a function of the rotational angle of the rotary elements 2, 30. For low power ranges of the driving engine, a relatively high transmission ratio can be selected, for example, and for high power ranges a relatively low transmission ratio can be selected.
With the apparatus shown as an example in FIGS. 1 and 2, the core 64 of the second part 66 of the transmission device and hence the control device as well can be adjusted by the control motor 130, in the regulated operating state, both in the direction of the arrow 270 and in the opposite direction. In the apparatus shown in FIGS. 4 and 5, an adjustment of the Bowden cable core 64 of the second part 66 of the transmission device and hence of the control device 6 by the control motor is intended only in the direction of the arrow 270.
In order to adjust the control device 6 via the control motor 130, for instance in the direction of the arrow 270, the third rotary element 80 must be rotated in a direction indicated by a further arrow 271, until the bearing face 96 comes to rest on the stop face 51, and the second rotary element 30 is rotated counter to the spring force of the tension spring 72. This moves the stop 46 of the second rotary element 30 away from the stop 19 of the first rotary element 2. The rotational angle of the third rotary element 80 is limited in the direction of the arrow 271 by the contact of the attachment 101 with the stop plate 182. Even an equally forceful actuation of the core 5 and hence of the first rotary element 2 counter to the direction of the arrow 269 has no effect, or virtually no effect, on the position of the core 64. An actuation of the first rotary element 2 counter to the direction of the arrow 269 can no lnger be transmitted to the second rotary element 30 and hence to the control device 6.
If the control motor 130 is to regulate motion in the other direction, i.e., counter to the direction of the arrow 270, which is provided for in the first exemplary embodiment (FIGS. 1-3), then the bearing face 97 of the third rotary element 80, for instance, must be made to contact the stop face 52 of the second rotary element 30, and the second rotary element 30 must be rotated by the third rotary element 80. The Bowden cable core 64 and the control device 6 are then adjusted counter to the direction of the arrow 270 as well. At the same time, however, the first rotary element 2 is rotated also. If the first part 1 of the transmission device is a cable, then the cable may sag somewhat; or if the first part 1 of the transmission device is a rod linkage, for example, then the operating element 3 is adjusted along with it somewhat, unless precautions against this are made in the rod linkage.
If adjustment via the control motor 130 is to be made in only one direction, then only one of the stop faces 51, 52 on the second rotary element 30 and only one of the bearing faces 96, 97 of the third rotary element 80 are needed.
If the control motor 130 is not triggered, then the reverse torsion spring means assures that the third rotary element 80 is returned to its position of repose. Since in the regulated operating state in the first exemplary embodiment (FIGS. 1 and 2) the Bowden cable core 64 and the control device 6 can be adjusted by the control motor 130 in both the direction of the arrow 270 and counter to it, the third rotary element 80 must be capable of being rotated out of its position of repose in both rotational directions from there, in each case up to a maximum angle. After the deflection of the third rotary element 80 in one direction, the reverse torsion spring means must be capable of restoring the third rotary element 80 in the opposite direction, and after deflection in the other direction, the reverse torsion spring means 155, 175 must likewise be capable of returning the third rotary element 80 in the opposite direction to its position of repose. The position of repose of the third rotary element 80 may extend over a certain rotational angle, depending on the design.
In the second exemplary embodiment (FIGS. 4 and 5), an adjustment of the Bowden cable core 64 and control device 6 by the control motor 130 is provided for only one direction, namely the direction of the arrow 270. It is accordingly sufficient if the reverse torsion spring means 155 is capable of restoring the third rotary element 80 in one one direction, that is, counter to the direction of the arrow 271. The reverse torsion spring means of the second exemplary embodiment (FIGS. 4 and 5) therefore includes only the reverse torsion spring 155.
In the first exemplary embodiment (FIGS. 1 and 2), if the third rotary element 80, in the regulated operating state, is rotated counter to the direction indicated by the arrow 271 out of its position of repose, the reverse torsion spring 175, which is one component of the reverse torsion spring means, is tensed by means of the attachment 102, which comes to rest on the second spring end 180 of the reverse torsion spring 175. The spring end 180 lifts from the stationary stop 184. The third rotary element can be rotated counter to the force of the reverse rotation spring 175 far enough that the second spring end 180, or part of the third rotary element 80, comes to rest on a stationary stop. If the third rotary element was rotated out of its position of repose counter to the direction of the arrow 271, then the restoring spring 175 can rotate the third rotary element 80 back again, until the second spring end 180 comes to rest on the stationary stop 184. Because of the stop 184, the reverse torsion spring 175 can be provided with an initial tension in the installed state.
In both exemplary embodiments, the third rotary element in the regulated operating state can be rotated out of its position of repose in the direction of the arrow 271 by the control motor 130. The reverse torsion spring means attempts to rotate the third rotary element 80 back into its position of repose. The reverse torsion spring 155, as part of the reverse torsion spring means, can act indirectly on the third rotary element 80, via the plate wheel 142 and the second drive wheel 144 (FIGS. 1 and 2) or via the drive wheel 144 alone (FIGS. 4 and 5). The reverse torsion spring 155 acts upon the third rotary element 80 counter to the direction of the arrow 271 until the position of repose is attained. In FIGS. 4 and 5, the reverse torsion spring 155 acts directly upon the second drive wheel 144, and via it then upon the third rotary element 80. To allow the reverse torsion spring 155 to act upon the third rotary element 80 in FIGS. 1 and 2, the first stop end 167 of the plate wheel 142 must come to rest on the first stop edge 171 of the drive wheel 144. Additionally, however, in the first exemplary embodiment (FIGS. 1 and 3) the third rotary element 80 must be capable of being adjusted by the control motor 130 past the position of repose defined by the reverse torsion spring 155, in the direction counter to the arrow 271. This happens in the first exemplary embodiment in that the drive wheel 144 can be rotated still farther relative to the plate wheel 142, causing the stop edge 171 to move away from the stop end 167. The drive wheel 144 can be rotated relative to the plate wheel 142 until on the other side the second stop edge 172 comes to rest on the second stop end 168 of the plate wheel 142.
In the first exemplary embodiment (FIGS. 1-3), on the one hand the reverse torsion spring 155 is supposed to be capable of rotating the third rotary element 80 counter to the direction of the arrow 271 back into the position of repose with sufficient force; on the other hand, it must be assured that the reverse torsion spring 155 does not rotate the third rotary element past its position of repose, yet as described above, continued rotation of the third rotary element 80 past this position of repose by the control motor 130 must still be possible.
To prevent the reverse torsion spring 155 from being capable, despite its initial tension, of rotating the third rotary element 80 backward past its position of repose, a catch mechanism is provided. The catch mechanism substantially comprises the plate wheel 142 and the star wheel 210. The number and angle of possible rotations of the plate wheel 142 are determined by the number of notches 226, 227 (FIG. 3) and indentations 222, 223 of the star wheel 210.
The plate wheel 142 cannot be rotated out of the position shown in FIG. 3 counter to the direction of and arrow 280 because the edge 232 of the plate wheel 142 is resting on the circumference 216 of the star wheel 210. If the plate wheel 142 is rotated out of the position shown if FIG. 3 in the direction of the arrow 180, then the dog 190 of the plate wheel 142, by engaging the first notch 226, rotates the star wheel 210 one increment farther, until the circumference 215 of the plate wheel 142 engages the first indentation 222 of the star wheel 210. As a result, a further rotation of the plate wheel 142 in the direction of the arrow 280 is enabled, until the dog 190 of the plate wheel 142 again rotates the star wheel 210 by one more increment by engaging the second notch 227. The circumference 215 of the plate wheel 142 thereupon engages the second indentation 223 of the star wheel 210. This enables a further rotation of the plate wheel 142 in the direction of the arrow 280, until the third rotary element 80 (FIGS. 1 and 2), with it attachment 101, strikes the stop plate 182. Depending on the desired rotational angle of the plate wheel 142, one notch 226, 227 or two or more notches 226, 227 may be provided in the star wheel 210. A correspondingly matched number indentations 222, 223 should then be provided.
The first drive wheel 131 joined to the rotor 132 of the control motor 130 turns the second drive wheel 144, which in turn can turn the third rotary element 80. The first drive wheel 131 meshes with the first disk portion 169 of the second drive wheel 144, and the second disk portion 170 of the second drive wheel 144 meshes with the third rotary element 180 via toothed profiles, and transmits a torque, generated by the rotor 132 of the control motor 130, to the third rotary element 80. However, the transmission of the torque may instead be effected by partly or completely replacing the toothed profiles of the drive wheels 131, 144 and of the third rotary element 80, for instance with friction linings, as a result of which a torque could be transmitted by friction.
The first reverse torsion spring 155 acts indirectly on the third rotary element 80 via the drive wheel 144. Because of the gear ratio between the drive wheel 144 and the third rotary element 80, this has the advantage that a restoring moment generated by the reverse torsion spring 155 is likewise stepped up or down, so that the restoring moment of the reverse torsion spring 155 can be lesser by design, in accordance with the gear ratio.
The reverse torsion spring 175 (FIGS. 1 and 2) acts directly upon the third rotary element 80. This has the advantage, especially if only a relatively small deflection of the reverse torsion spring 175 is intended, that a relatively strong flat strip can be used for this spring because of the relatively slight deflection; as a result, a sufficiently high restoring moment can also be generated upon the third rotary element 80.
In the first exemplary embodiment shown in and described in detail in conjunction with FIGS. 1 and 2, it is possible in the regulated operating state for the second rotary element 30 to rotated by the control motor 130 in both rotational directions. Thus the Bowden cable core 64 and the thus the control device 6 can be adjusted in either direction.
If the rotation of the second and third rotary elements 30, 80 by the control motor 130 is intended to be possible in only one direction, then one of the two reverse torsion springs 155, 175 suffices for the reverse torsion, because in that case the reverse torsion needs to be operative in only one direction. If the reverse torsion means comprises only the reverse torsion spring 155, for instance, as is the case in the second exemplary embodiment (FIGS. 4 and 5), then the catch mechanism, comprising the plate wheel 142 and the star wheel 210, can be omitted, because in that case the reverse torsion spring 155 is capable of rotating the third rotary element 80 backward far enough that the attachment 102 on the third rotary element 80 comes to rest on a stationary stop plate 282, for instance attached to the base plate 120. The second end 157 of the reverse torsion spring 155 can then be disposed directly on the drive wheel 144. If the reverse torsion means comprises only the reverse torsion spring 175, then the stop 184 for the reverse torsion spring 175 on the base plate can be omitted, because the reverse torsion spring 175 can rotate the third rotary element backward far enough that a portion, intended for this purpose, of the third rotary element 80 comes to rest on a stationary stop. The catch mechanism 142, 210 can be omitted as well.
For the reverse torsion, two differently embodied reverse torsion springs 155, 175 were suitably selected in the first exemplary embodiment (FIGS. 1 and 2). However, it is also possible for both of these reverse torsion springs to be embodied and deflected like either the spring 155 or the spring 175. It would also be possible for the two reverse torsion springs 155, 175 to exchange places with one another.
By inserting a second drive wheel 144 between the first drive wheel 131 and the third rotary element 80, it is also possible to keep the center-to-center distance between the rotor 132 of the control motor 130 and the first shaft 110, on which the rotary elements 2, 30 and 80 are disposed, rather short. The first drive wheel 131 is then disposed in such a way with respect to the third rotary element 80 that it does not protrude radially past the outer circumference thereof.
The toothed profile 92 of the third rotary element 80 extends only in the vicinity of the partial ring 87, which provides a certain compensation in weight for the attachments 101, 102, which are disposed somewhat to one side.
The control motor 130 may be a rotary motor, or a linear motor producing a longitudinal motion. It may be driven electrically, hydraulically, pneumatically, or the like.
The apparatus according to the invention can be used with transmission devices between the operating element 3 and the control device 6 for the driving engine, for instance in stationary engines and in self-propelled engines, such as in passenger cars and trucks. The operating element may for example be hand- or foot-actuated. The transmission device, with the operating element and the control device, may be designed in such a way that the operating element returns to an initial position if an operating force disappear. On the other hand, it may instead be such that if the operating force disappears it remains in any previously set position. The driving engine may be any type of engine the output of which is determinable by the control device, an example being an internal combustion engine.
To enable adjusting the output between a minimum and a maximum value, the second rotary element 30 must be rotatable in two rotational directions (FIG. 1) by at least an angle alpha (α) between a first terminal position and a second terminal position. It may be provided that this angle alpha (α) is attainable only in the unregulated operating state via the operating element 3, or only in the regulated operating state via the control motor 130 and the third rotary element 80. On the other hand, it may also be that the first terminal position, for instance, in one rotational direction is attainable only via the control motor, while the second terminal position is attainable only via the operating element 3. If in the unregulated operating state the output can be adjusted between the maximum and the minimum value via the operating element 3 or Bowden cable core 5, without causing the rotation of the third rotary element 80 and control motor 130, then the recess 94 must be large enough not to prevent a rotation of the second rotary element 30 by the angle alpha (α).
As described above, in the apparatus described in terms of the second exemplary embodiment (FIGS. 4 and 5), the Bowden cable core 64 can be adjusted by the control motor 130 in the direction of the arrow 270. This apparatus can therefore serve in a motor vehicle, for example, upon startup and in acceleration, to prevent or limit drive slip between the driven wheels and the road surface. As soon as suitable sensors detect drive slip, i.e., a loss of traction, the control motor 130 is triggered via an electronic control unit. Via the rotary elements 80 and 30 and the Bowden cable core 64, the control motor 130 then adjusts the control device 6 toward reduced output by the driving engine, until the sensors can no longer detect excessive drive slip.
In the apparatus described in conjunction with the first exemplary embodiment (FIGS. 1-3), the Bowden cable core 64 can be adjusted by the control motor 130 in both the direction of the arrow 270 and the opposite direction. In a motor vehicle, for instance, this apparatus can therefore be used not only to prevent drive slip but also to prevent or limit braking slip, resulting from a braking moment of the driving engine, between the driven wheels and the road surface. As soon as suitable sensors detect braking slip, the control motor 130 is again triggered via the electronic control unit, such that via the rotary elements 80 and 30 the control motor adjusts the cable core 64 counter to the direction of the arrow 270 and hence adjusts the control device 6 in the direction of higher output, until the sensors can no longer detect excessive braking slip.
Drive slip may for instance arise if the operating element 3 is actuated overly forcefully in the direction of higher output. Braking slip may arise, for instance, if the operating element 3 is suddenly actuated in the direction of reduced output and/or when a transmission located between the driven wheels and the driving engine is shifted into a lower gear. Both drive slip and braking slip have a negative effect on the performance of the motor vehicle.
When the control motor 130 is triggered via a suitable electronic control unit, then the apparatus can also be used, in a self-propelled engine such as in a passenger car, for instance, for automatic vehicle speed control or for cruise control.
Of many applications for the apparatus, in the version of the first exemplary embodiment (FIGS. 1 and 2), the following example of a possible case can be given, on the following assumptions: Use in a passenger car with the driving engine in the form of an internal combustion engine with externally supplied ignition; a throttle valve in the intake tube as the control device 6; a gas pedal as the operating element 3; and a Bowden cable as the transmission device 1, 66. An adjustment of the control device 3/Bowden cable core 64 in the direction of the arrow 270 represents a reduction in output. An adjustment in the opposite direction effects an increase in output. The restoring spring 266 acts on the control device 6 in the direction of minimal output. The operating force can act on the operating element 3, in this case the gas pedal, counter to the restoring spring 266.
The following conditions are also assumed:
(a) If the operating force disappears, in the unregulated operating state, the output should not drop below an increased idling output; hence reliable operation under all conditions, for instance when the engine is cold, is assured.
(b) In the unregulated operating state, the engine should be adjustable via the operating element 3/ gas pedal without causing the control motor 130 and the third rotary element 80 to rotate as well.
(c) As needed, for instance when the engine is warm, the control motor 130 should be capable via the third rotary element 80 of lowering the actual output to below the increased idling output.
(d) If a set-point output determined by an electronic unit is less than the output equivalent to an instantaneous gas pedal position, for example because driven wheels are spinning, then it should be possible to reduce the output.
(e) At a gas pedal position equivalent to a relatively low output, it should be possible to increase the actual output, for instance in the event of overly high engine braking moment, but for safety reasons, for instance, only up to a firmly defined value.
To meet condition (a), a stop (not shown) on the first rotary element or a stop of the Bowden cable core 5 in the first part of the transmission device, or a stop on the gas pedal, must in particular assure that the restoring spring 266 can retract the control device 6 or the second rotary element 30 in the direction of the arrows 269, 270 only as far as a zero position, corresponding to the increased idling output. The zero position of the second rotary element 30 is shown in FIG. 1 as a dot-dash line 285. To meet condition (b), the recess 94 must in particular be sufficiently large, and the second rotary element 30 must be movable counter to the direction of the arrow 270 via the first rotary element 2 into the terminal position equivalent to maximal output. To this end, the second rotary element 30 must be freely rotatable relative to the third rotary element 80 by an angle delta (δ) (FIG. 1). To meet condition (c), the control motor 130 must in particular be capable, via the third rotary element 80, of adjusting the second rotary element 30 past the zero position in the direction of the arrow 270. This angle in the direction of lesser output is likewise limitable, via stops, to an angle gamma (γ). To meet condition (d), the control motor 130 must in particular be capable, via the third rotary element 80, of rotating the second rotary element 30 to a variable extent in the direction of the arrow 270. To meet condition (e), the control motor 130 must in particular be capable of rotating the third rotary element out of its position of repose by an angle beta (β) (FIG. 1) counter to the direction of the arrow 271. By means of a stop, for instance between the third rotary element 80 and the base plate 120, the angle beta (β) is reliably defined. Depending on the initial position, the second rotary element 30 is rotated maximally by the angle beta (β) counter to the direction of the arrow 270. Even in the event of a malfunction of the control motor 130 or an error in the control signals acting on the control motor, the angle beta (β) and hence the output cannot be unintentionally exceeded.
The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | An apparatus for motor vehicles having traction control and/or anti-lock brakes. In a known apparatus, a distinction can be made between an unregulated and a regulated operating stage. In the regulated operating state, the position of a control device is determined by means of a control motor. In the unregulated operating state, a position of an operating element is transmitted to a control device with the aid of the transmission device. When the operating element is adjusted and the control device is restored by a restoring spring, however, a rotor of a control motor is adjusted along with them. This requires great actuation forces and a strong restoring spring. In this system, a third rotary element is provided. In the unregulated operating state, the third rotary element returns to a position of repose. In that case there is then no longer any operative connection between the transmission device and the control motor. The control device can thus be adjusted by the operating element with relative slight actuating forces. Nor is a relatively strong restoring spring necessary. Even if an electronic control system should fail, the control device can be adjusted without problems via the operating element. The apparatus is particularly suitable for motor vehicles having traction control and/or anti-lock brakes. | 1 |
BACKGROUND
[0001] FIG. 1 shows a perspective view of a typical computer 100 where a top cover (not shown) of a chassis 101 is removed. As can be seen in FIG. 1 , various kinds of electronic parts 102 are disposed on a circuit board 103 of the computer 100 . The circuit board 103 is disposed on a bottom surface of the chassis 101 via supports 105 .
[0002] FIG. 2 shows a perspective view of the computer 100 in FIG. 1 where an expansion card 201 and the attachment part 206 are installed. As can be seen in FIG. 2 , similar to the circuit board 103 of the computer 100 , the circuit board 203 of the expansion card 201 has various kinds of electronic parts 202 thereon.
[0003] The chassis 101 includes an attachment part 206 . Attachment part 206 is constituted by a left side surface of chassis 101 and a wall 207 disposed in the middle of the chassis 101 . The supports 205 and 208 are disposed on a left and right end of the circuit board 203 of the expansion card 201 , and the support 205 and 208 are disposed on the end surface of the circuit board 203 , for example, by screws (not shown). Also, the supports 205 and 208 are attached to the chassis 101 and the wall 207 respectively, for example, by screws (not shown) so that the expansion card 201 is installed in the chassis 101 .
SUMMARY OF INVENTION
[0004] One or more embodiments of the present invention relate to an air baffle with an integrated expansion card attachment for receiving an expansion card having a handle attached thereto, the air baffle comprising: a first wall comprising a first guide and a second guide projecting from a side surface of the first wall, wherein the first guide a second guide form a transverse space therebetween; and a second wall parallel to the first wall disposed a distance from the first wall approximately equal to a width of the expansion card, wherein the second wall comprises a snap retainer having a projected portion thereof, wherein the transverse space formed between the first and second guides of the first wall has a size approximately equal to a thickness of the expansion card such that a first end of the expansion card is firmly held by the first guide and the second guide when the expansion card is inserted into the transverse space, wherein the projected portion inserts between the handle attached to the expansion card and the expansion card in order to hold the expansion card in place, and wherein the expansion card is held apart from and parallel to a circuit board of a computer such that an air channel is created between the first wall and the second wall for air to pass across the circuit board of the computer and the expansion card.
[0005] One or more embodiments of the present invention relate to a computer system comprising: a circuit board disposed within a chassis; an air baffle with an integrated expansion card attachment disposed within the chassis; an expansion card having a handle attached thereto; wherein the air baffle comprises: a first wall comprising a first guide and a second guide projecting from a side surface of the first wall, wherein the first guide a second guide form a transverse space therebetween; and a second wall parallel to the first wall disposed a distance from the first wall approximately equal to a width of the expansion card, wherein the second wall comprises a snap retainer having a projected portion thereof, wherein the transverse space formed between the first and second guides of the first wall has a size approximately equal to a thickness of the expansion card such that a first end of the expansion card is firmly held by the first guide and the second guide when the expansion card is inserted into the transverse space, wherein the projected portion inserts between the handle attached to the expansion card and the expansion card in order to hold the expansion card in place, and wherein the expansion card is held apart from and parallel to a circuit board of a computer such that an air channel is created between the first wall and the second wall for air to pass across the circuit board of the computer and the expansion card.
[0006] Other aspects and advantageous of the invention will be apparent from the following description and appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0007] FIG. 1 shows a perspective view of a typical computer where a top cover of a chassis is removed.
[0008] FIG. 2 shows a perspective view of a computer in FIG. 1 where an expansion card is installed.
[0009] FIG. 3 shows a perspective view of the computer where a top cover of the chassis is removed.
[0010] FIG. 4 shows an enlarged view of the first wall as shown in FIG. 3 including others.
[0011] FIG. 5 shows an enlarged view of a part of the second wall, which shows a snap retainer.
[0012] FIG. 6 shows a perspective view of an expansion card.
[0013] FIG. 7 shows a back surface of the expansion card, to which the handle is attached.
[0014] FIG. 8 shows a perspective view of the handle.
[0015] FIG. 9 shows a perspective view of the computer where the expansion card is installed.
[0016] FIG. 10 shows a flow diagram of installing the expansion card.
[0017] FIGS. 11 (A)-(C) shows the expansion card and the snap retainer when installing the expansion card.
DETAILED DESCRIPTION
[0018] Specific embodiments of the invention will now be described in detail with reference to the accompanying figures. Like elements in the various figures are denoted by like reference numerals for consistency.
[0019] In the following detailed description of embodiments of the invention, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.
[0020] FIG. 3 shows a perspective view of a part of computer 300 having an attachment for an expansion card before installing the expansion card (not shown). As can be shown in FIG. 3 , a computer 300 has various kinds of electronic parts 301 , components or units, such as integrated circuits, transistors, processors, heat sinks, connectors, etc. on the circuit board 302 of the computer 300 . Such electronic parts, components or units 301 are enclosed in the chassis 303 . In one or more embodiments, the present invention uses the circuit board 302 as a bottom wall, employs two side walls, and uses the expansion card itself as a top wall of an air channel for air to flow across the electronic components of the circuit board 302 and the expansion for cooling.
[0021] The attachment for an expansion card includes the first wall 304 and the second wall 305 . The first wall 304 is disposed on the circuit board 302 of the computer 300 at a side of a slot 306 approximately perpendicular to the circuit board 302 . Also, the second wall 305 is disposed on the circuit board 302 at a side of a slot 307 approximately perpendicular to the circuit board 302 and parallel to the first wall 304 . The first wall 304 and the second wall 305 may be disposed on the circuit board 302 by screws, adhesives, bonding or other attachment methods known in the art. Also, one end of the first wall 304 is disposed at a side of the inside surface of the chassis 303 . Similarly, one end of the second wall 305 is disposed at a side of the inside surface of the chassis 303 . As a result, the part D of the circuit board 302 of the computer 300 is surrounded by the first wall 304 , the second wall 305 , and a part of the chassis 303 . Further, the third wall 308 is attached to the first wall 304 by a plurality of rods 310 . Similarly, the fourth wall 309 is attached to the second wall 305 by a plurality of rods 311 .
[0022] FIG. 4 shows an enlarged view of FIG. 3 oriented towards the first wall. As can be shown in FIG. 4 , the first wall 304 has a plurality of first guides 401 - 404 and a plurality of second guides 405 - 407 . The first guides 401 - 404 and the second guides 405 - 407 are disposed on a side surface of the first wall 304 in a line at a different height respectively so that there is a transverse space horizontally between the bottom surface of the first guides 401 - 404 and the top surface of the second guides 405 - 407 . The first guides 402 and 403 and the second guides 405 - 407 are disposed alternately along the each line. The width of this transverse space between the first guides 401 - 404 and the second guides 405 - 407 is approximately the same as the thickness of a circuit board of an expansion card as explained below. The shape and size of the second guides 405 - 407 are the approximately same as the first guides 402 and 403 , but the first guides 401 and 402 are smaller than the second guides 405 - 407 in width. The first guide 401 is disposed above the second guide 405 , and the first guide 404 is disposed above the end the second guide 407 . In addition, the transverse space has openings 408 - 410 on the second guides 405 - 407 . In one or more embodiments, the first and second guides 401 - 407 are formed integrally as a part of the first wall 304 . One skilled in the art will appreciate that these guides could be separately formed and attached to the first wall.
[0023] Further, as explained above, the third wall 308 is attached to the first wall 304 by a plurality of rods 310 . Specifically, as shown in FIG. 4 , rods 310 include three rods 411 - 412 . One end of the rod 411 is attached to one top end of the first wall 410 , and one ends of rods 412 and 413 are attached in the middle of the other ends of the first wall 410 respectively. The rod 412 is approximately parallel to the first wall while the rods 411 and 413 have the same predetermined angle to the side surface of the first wall. Also, the rod 411 is parallel to the rod 413 . The rods 411 and 413 and the rod 412 are crossed in the middle of the rods 411 - 413 in the air, and the other ends of the rods 411 - 413 are attached to the third wall 308 at the end thereof. Thus, the third wall 308 is supported in the air above the circuit board 302 at a predetermined angle to the side surface of the first wall 304 . Because the fourth wall 309 is supported by the second wall 305 similarly although the direction of the rods 312 and the fourth wall 309 are opposite, as can be shown in FIG. 3 , the explanation regarding the fourth wall 309 and the rods 312 are omitted.
[0024] One of the ordinary skilled in the art will appreciate that any other shapes or numbers of the first guides 401 - 404 and the second guides 405 - 407 may be used so long as the expansion card 600 is firmly held by these guides and the air passes smoothly when the expansion card 600 is installed, as described below. Also, one of the ordinary skilled in the art will appreciate other positions or numbers of the rods or ways to support the third and fourth wall 308 and 309 may be employed so long as the direction of the air is changed effectively by the third 308 and fourth wall 309 as explained below. In addition, there may be no openings 408 - 410 at the space between the first guides 401 - 404 and the second guides 405 - 407 .
[0025] FIG. 5 shows an enlarged view of a part of the second wall, which shows a snap retainer. As can be shown in FIG. 5 , the snap retainer 501 is integrally formed as a part of the second wall 305 . The snap retainer 501 is disposed parallel to the second wall 305 , and the height and the thickness of the snap retainer 501 are approximately the same as the second wall 305 . There are two cut outs 504 and 505 at the sides of the snap retainer 501 such that the snap retainer 501 is flexibly supported by the lower part of the second wall 305 . Also, the snap retainer 501 itself may be flexible.
[0026] Further, the snap retainer 501 has a projected portion 502 in the middle upper part thereof which is disposed on the surface of the snap retainer 501 and parallel to the circuit board 307 . The shape of the projected portion 502 is approximately triangle in the sectional view, and the width becomes narrower toward the tip of the projected portion 502 . Furthermore, the position of the projected portion 502 to the circuit board 302 of the computer 300 is approximately the same as the position of the space between the first guides 401 - 404 and the second guides 405 - 407 so that the expansion card 600 is held approximately parallel to the circuit board 302 of the computer 300 when the expansion card 600 is attached, as described below. In addition, there is a thick portion 503 at the top of the snap retainer 501 . Those skilled in the art will appreciate that the height at which the expansion card 600 is held above the circuit board 302 may vary depending on the type of computer 300 is involved.
[0027] One of the ordinary skilled in the art will appreciate that other shapes, sizes, or numbers of the projected portion 502 may be employed so long as the expansion card 600 is firmly held by the projected portion 502 and an air passes smoothly between the circuit board 302 of the computer 300 and the expansion card 600 as explained below. Also, in one or more embodiments, the projected portion 502 and the snap retainer 501 are formed integrally as a part of the second wall 305 . However, the projected portion 502 and the snap retainer 501 may be separately formed and attached to the snap retainer 501 and the second wall 305 .
[0028] FIG. 6 shows a perspective view of an expansion card 600 . FIG. 7 shows a back surface of the expansion card 600 , to which the handle 701 is attached. FIG. 8 shows a perspective view of the handle 701 . As can be shown in FIG. 6 , various electronic parts 601 are disposed on the circuit board 602 . As can be shown in FIG. 7 , the handle 701 is attached to the back surface of the circuit board of the expansion card 600 at one end of the circuit board 602 . As can be shown in FIG. 8 , the handle 701 has a support 801 , a guide portion 802 , and a handle portion 803 . The support 801 may be attached to the bottom surface of the circuit board 602 by screws, adhesives, bonding or other attachment methods known in the art. The distance between the guide portion 802 and the bottom surface of the circuit board 602 is longer than the distance between the handle portion 803 and the bottom surface of the circuit board 602 . Thus, it is easily held by fingers using the handle portion 803 . In addition, one of the ordinary skilled in the art will appreciate that other shapes, sizes, or numbers of handle 701 may be used so long as the expansion card 600 is firmly held by the projected portion 502 as described below.
[0029] FIG. 9 shows a perspective view of the computer where the expansion card 600 is installed. As can be seen in FIG. 9 , the end circuit board 602 is inserted between the first guides 401 - 404 and the end the guides 405 - 407 . Also, the projected portion 502 of the snap retainer 501 is inserted between the back surface of the circuit board 602 and the bottom surface of the guide portion 802 of the handle 701 . As a result, the expansion card 600 is held firmly between the first wall 304 and the second wall 305 above and approximately parallel to the circuit board 302 of the computer 300 as described in detail below.
[0030] In operation, when the expansion card 600 is installed to the attachment, which includes the first wall 304 and the second wall 305 , there is an opening between the circuit board 302 of the computer 300 and the circuit board 602 of the expansion card 600 so that an air passes between them smoothly and the ventilation of the computer 300 is improved. The use of the expansion card itself as a wall of air channel eliminates the need for a separate part and saves production cost. In one or more embodiments, the expansion card 600 is attached to the attachment facing downward such that the electronic parts 601 of the expansion card 600 are cooled by the air passing through the air channel. Further, as can be shown in FIG. 3 , by the third wall 308 and forth wall 309 , the air from the parts A-C gathers and enters into the part D shown in FIG. 3 where the expansion card 600 is installed. Thus, electronic parts 601 and 301 on the part D of the circuit board 302 and on the expansion card 600 are effectively cooled. In addition, the angle of the third wall 308 and forth wall 309 may be adjusted to effectively send the air from the parts A-C to the part D.
[0031] FIG. 10 shows a flow diagram of installing the expansion card to the computer. In one or more embodiments of the invention, one or more of the steps described below may be omitted, repeated, and/or performed in a different order. FIGS. 11 (A)-(C) show the expansion card 600 and the snap retainer 501 when installing the expansion card 600 .
[0032] First, the handle 701 is attached to the back surface of the circuit board 602 of the expansion card 600 (Step 901 ). Second, one end of the expansion card 600 , which does not have the handle 701 , is inserted to the transverse space between the first guides 401 - 404 and the second guides 405 - 407 (Step 902 ). At this time, the other end of the expansion card 600 has not yet contacted to the projected portion 502 so that the snap retainer 501 is perpendicular to the circuit board 302 of the computer 300 as shown in FIG. 11 (A). Third, the other end of the expansion card 600 is pushed down toward the projected portion 502 using the handle portion 803 of the handle 701 . While pushing down the expansion card, the projected portion 502 is moved back by the bottom surface of the expansion card 600 as shown in FIG. 11 (B) because the snap retainer 501 is flexibly held by the second wall 305 . Then, the end of the circuit board 602 passes the tip of the projected portion 502 , and, the projected portion 502 is finally inserted between the bottom surface of the guide portion 802 of the handle 701 and the top surface of the circuit board 602 as shown in FIG. 11 (C) (Step 903 ). At this time, because the snap retainer 501 is flexibly held by the second wall 305 and the shape of the projected portion 502 is triangle in the sectional view as explained above, the circuit board 602 of the expansion card 600 is firmly held by the projected portion 502 and the transverse space of the first wall 304 .
[0033] In view of above, this attachment provides a simple, tool-less, user-friendly mechanism for installing an expansion card. Also, the expansion card 600 is also used as a part of an air baffle when attached so that the electronic parts 301 and 601 of the computer 300 and the expansion card 600 are effectively cooled. Also, this use of the expansion card 600 to create an air channel within the air baffle allows for the improved use of the limited space in the chassis 303 of the computer 300 . Further, this use of the expansion card 600 itself as a wall for defining the air channel reduces the number of the parts to form such an air baffle and reduces cost.
[0034] While the invention 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 can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. | An air baffle with an integrated expansion card attachment is disposed in a computer for receiving an expansion card having a handle attached thereto. The air baffle includes a first wall including a first guide and a second guide projecting from a side surface of the first wall. The first guide a second guide form a transverse space therebetween. The air baffle includes a second wall parallel to the first wall disposed a distance from the first wall approximately equal to a width of the expansion card. The second wall includes a snap retainer having a projected portion thereof. The transverse space formed between the first and second guides of the first wall has a size approximately equal to a thickness of the expansion card such that a first end of the expansion card is firmly held by the first guide and the second guide when the expansion card is inserted into the transverse space. The projected portion inserts between the handle attached to the expansion card and the expansion card in order to hold the expansion card in place. The expansion card is held apart from and parallel to a circuit board of a computer such that an air channel is created between the first wall and the second wall for air to pass across the circuit board of the computer and the expansion card. | 7 |
RELATED APPLICATION
[0001] The present disclosure relates to subject matter contained in priority Korean Application No. 10-2008-0094954, filed on Sep. 26, 2009 and U.S. Patent Application No. 61/136,711, filed on Sep. 26, 2008, which are herein expressly incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a liquid storage container and a clothes dryer having the same, and particularly, to a liquid storage container capable of storing liquid material such as fragrant material sprayed into a drum of a clothes dryer, and the clothes dryer having the same.
[0004] 2. Background of the Invention
[0005] In general, a clothes dryer indicates an apparatus for drying laundry having completely undergone a dehydration process after a washing process, by introducing the laundry into, a drum of the clothes dryer, and by evaporating moisture inside the laundry by supplying hot blast into the drum.
[0006] The clothes dryer comprises a drum disposed in the clothes dryer and into which laundry is introduced, a driving motor for driving the drum, a blow fan for blowing air into the drum, and a heating means for heating the air introduced into the drum.
[0007] The heating means may use high-temperature electric resistance heat generated by using an electric resistance, or combustion heat generated by combusting gas.
[0008] Air having been discharged from the drum contains moisture of the laundry inside the drum, thereby changing into high-temperature humid air. According to a method for processing the high-temperature humid air, the clothes drier may be classified. More concretely, the clothes drier is classified into a condensation type clothes dryer for condensing moisture inside high-temperature humid air by heat-exchanging the high-temperature humid air with external air through circulation in the clothes dryer without discharging the high-temperature humid air out of the clothes dryer, and an exhaustion type clothes dryer for directly discharging high-temperature humid air having passed through the drum to the outside.
[0009] When drawing the laundry having completely undergone a washing process out of a washing machine so as to introduce the laundry into the clothes dryer, a user may have discomfort in smelling odor of used washing water and detergent, or odor of the laundry prior to the washing process. Accordingly, it was required to supply fresh feeling of the laundry to the user by removing the odor of the laundry. For this end, there have been efforts to supply functional material such as fragrant material into the drum. The fragrant material to be stored in a storage container has to be supplied with an appropriate amount corresponding to a usage amount. Accordingly, there has been required a means to allow the user to conveniently check a remaining amount of the fragrant material inside the storage container.
SUMMARY OF THE INVENTION
[0010] Therefore, an object of the present invention is to provide a liquid storage container capable of storing liquid material and easily checking a remaining amount of the liquid material.
[0011] Another object of the present invention is to provide a clothes dryer having a liquid storage container capable of easily checking a remaining amount of liquid material.
[0012] To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a liquid storage container, comprising: a reservoir installed at a clothes dryer, and configured to store liquid therein; a light transmitting window disposed above the reservoir; and a level indicator disposed to form an acute angle with respect to the surface of the light transmitting window, and configured to be partially or wholly immersed into the liquid stored in the reservoir according to a level of the liquid.
[0013] According to the amount of the liquid stored in the reservoir, an immersed degree of the level indicator into the liquid may become different. Accordingly, a user may check a remaining amount of the liquid with his or her naked eyes. Especially, the level indicator may be disposed to form an acute angle with respect to the surface of the light transmitting window. Accordingly, even if the light transmitting window is located above the clothes dryer, the entire level indicator may be easily checked. This may allow the user to precisely and conveniently check the remaining amount of the liquid.
[0014] The level indicator may be implemented as a calibration display portion. The calibration display portion may include numbers or characters for providing information about a remaining amount of the liquid, on a side surface of a calibration.
[0015] The calibration display portion may be protruding from a bottom surface of the reservoir, or may be integrally formed with the reservoir.
[0016] The level indicator may be a plate-type calibration display portion. The plate-type calibration display portion may be separately formed from the reservoir. In this case, a lower side of the plate-type calibration display portion may be utilized as a storage space, which enhances a spatial utilization degree.
[0017] The level indicator may be arranged at the center of the reservoir, or may be arranged so as to contact an inner wall of the reservoir.
[0018] The liquid storage container may further comprise a guide groove extending along the level indicator, and a floating member which moves along the guide groove. Even in the case that transparent liquid is stored in the liquid storage container, an immersed degree of the level indicator into the transparent liquid may be easily checked by a user.
[0019] According to another aspect of the present invention, there is provided a liquid storage container, comprising: a reservoir installed at a clothes dryer, and configured to store liquid therein; a light transmitting window disposed above the reservoir; and a level indicator disposed to form an acute angle with respect to the surface of the liquid stored in the reservoir, and configured to be partially or wholly immersed into the liquid stored in the reservoir according to a level of the liquid.
[0020] According to still another aspect of the present invention, there is provided a clothes dryer, comprising: a body; a drum rotatably installed in the body; a liquid supplying apparatus configured to supply liquid material into the drum; and a liquid storage container comprising: a reservoir installed at the body, and configured to store liquid therein; a light transmitting window disposed above the reservoir; and a level indicator disposed to form an acute angle with respect to the surface of the light transmitting window, and configured to be partially or wholly immersed into the liquid stored in the reservoir according to a level of the liquid, wherein the liquid storage container may be one of the aforementioned liquid storage containers.
[0021] According to yet still another aspect of the present invention, there is provided a clothes dryer, comprising: a body; a drum rotatably installed in the body; a liquid supplying apparatus configured to supply liquid material into the drum; and a liquid storage container comprising: a reservoir installed at the body, and configured to store liquid therein; a light transmitting window disposed above the reservoir; and a level indicator disposed to form an acute angle with respect to the surface of the liquid stored in the reservoir, and configured to be partially or wholly immersed into the liquid stored in the reservoir according to a level of the liquid, wherein the liquid storage container may be one of the aforementioned liquid storage containers.
[0022] According to yet still another aspect of the present invention, there is provided a liquid storage container, comprising: a reservoir installed at a clothes dryer, and configured to store liquid therein; a light transmitting window disposed above, the reservoir; and, a level indicator installed in the reservoir, and configured to be partially or wholly immersed into the liquid stored in the reservoir according to a level of the liquid.
[0023] According to yet still another aspect of the present invention, there is provided a clothes dryer, comprising: a body; a drum rotatably installed in the body; a liquid supplying apparatus configured to supply liquid material into the drum; and a liquid storage container, wherein the liquid storage container comprises: a reservoir installed at the body, and configured to store liquid therein; a light transmitting window disposed above the reservoir; and a level indicator installed in the reservoir, and configured to be partially or wholly immersed into the liquid stored in the reservoir according to a level of the liquid.
[0024] In the present invention, an immersed degree of the level indicator into the liquid, stored in the reservoir may become according to a level of the liquid, which may be easily checked by a user. This may allow the user to conveniently and rapidly check a remaining amount of the liquid.
[0025] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
[0027] In the drawings:
[0028] FIG. 1 is a perspective view of a clothes dryer having a liquid storage container according to a first embodiment of the present invention;
[0029] FIG. 2 is an enlarged perspective view of the liquid storage container of FIG. 1 ;
[0030] FIG. 3 is a perspective view of a bottom surface of the liquid storage container of FIG. 2 ;
[0031] FIG. 4 is a perspective view of a clothes dryer having a liquid storage container according to a second embodiment of the present invention;
[0032] FIG. 5 is a sectional view of the liquid storage container of FIG. 4 ; and
[0033] FIG. 6 is a cut-out perspective view of a clothes dryer having a liquid storage container according to a third embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Description will now be given in detail of the present invention, with reference to the accompanying drawings.
[0035] Hereinafter, a liquid storage container and a clothes dryer having the same according to the present invention will be explained in more detail with reference to the attached drawings.
[0036] FIGS. 1 to 3 show an inner structure of a clothes dryer having a liquid storage container according to a first embodiment of the present invention. FIG. 1 shows only an inner structure of the clothes dryer except for an outer panel. In the preferred embodiment of FIGS. 1 to 3 , the liquid storage container has been applied to the clothes dryer. However, the liquid storage container may be also applied to any apparatus for containing specific liquid to be supplemented. For instance, the liquid storage container of FIG. 1 . may be also applied to a washing machine having a drying function.
[0037] An upper side of the clothes dryer constitutes an upper plate 10 . The upper plate 10 forms the appearance of the clothes dryer together with a front plate, side plates, and a rear plate. A front supporter 20 is disposed at a front side of the clothes dryer. The front supporter 20 is disposed on a front surface of a drum 30 , and rotatably supports the drum 30 together with a rear supporter (not shown).
[0038] A reservoir 100 for storing fragrant material therein is installed on a bottom surface of the upper plate 10 . The reservoir 100 may serve to store therein not only fragrant material, but also any liquid material. A fragrant material supplying pipe 110 connected to a nozzle (not shown) through which fragrant material is sprayed into the drum 30 is connected to one side surface of the reservoir 100 . And, a fragrant material discharging pipe 112 is connected to a bottom surface of the reservoir 100 . The fragrant material discharging pipe 112 serves to discharge fragrant material remaining in the reservoir 100 when other type of fragrant material is to be sprayed into the drum 30 .
[0039] A cut-out portion 12 is disposed on the upper plate 10 at a position above the reservoir 100 . The reservoir 100 is arranged so that a reservoir cover 102 can be exposed out through the cut-out portion 12 . An introduction opening 104 is formed at the reservoir cover 102 , and the introduction opening 104 may be opened or closed by a lid 120 A cover 130 configured to open or close the cut-out portion 12 is rotatably coupled to one side of the cut-out portion 12 .
[0040] A central portion of the bottom surface of the reservoir 100 is upwardly protruding to form a calibration display portion 106 . As both side walls 108 of the calibration display portion 106 are connected to the bottom surface of the reservoir 100 , the calibration display portion 106 and the reservoir 100 are integrally formed with each other. Here, the calibration display portion 106 is arranged so that its surface can form an acute angle with respect to the surface of the reservoir cover 102 corresponding to an upper surface of the reservoir 100 . Also, the surface of the calibration display portion 106 forms an acute angle with respect to the surface of liquid stored in the reservoir 100 . The angle may be determined according to a height and a width of the reservoir 100 . For instance, the calibration display portion 106 may be arranged so as to have a length corresponding to ⅔ of a length of the bottom surface of the reservoir 100 or more than.
[0041] Preferably, the introduction opening is arranged in a direction perpendicular to the calibration display portion 106 without overlapping each other. This may prevent liquid put into the introduction opening for supplementation from colliding with the surface of the calibration display portion 106 thereby dispersing out.
[0042] Calibrations 109 are formed on the surface of the calibration display portion 106 . Alternatively, the surface of the calibration display portion 106 may be divided into a plurality of regions, and the regions may be set to have different colors from each other. As another example, information corresponding to calibrations, such as substantial numeric values or maximum or minimum values may be displayed near the calibration.
[0043] Hereinafter, the operation of the liquid storage container will be explained in more detail.
[0044] Once fragrant material is put in the reservoir 100 , the calibration display portion 106 is partially or entirely immersed into the fragrant material according to a level of the fragrant material. For instance, when the fragrant material is filled-up in the reservoir 100 , the upper side of the calibration display portion 106 has a maximum level. However, as the fragrant material is continuously used, the level of the calibration display portion 106 is gradually lowered.
[0045] A user can periodically check a remaining amount of the fragrant material, and can supplement the fragrant material by opening the cover 130 . Since the reservoir 100 is disposed on the upper plate 10 , the user's eyes are toward the lower side from the upper side of the reservoir cover 102 . Since the calibration display portion 106 is arranged so as to form an acute angle with respect to the surface of the reservoir cover 102 , an angle between the user's eyes and the surface of the calibration display portion 106 becomes close to a right angle. Accordingly, the user can easily check a remaining amount of the fragrant material. This is more facilitated when the reservoir has a higher height and a narrower width.
[0046] In the case that the fragrant material is transparent, the user may have a difficulty in recognizing the level of the calibration display portion. For this, a guide groove extending in a lengthwise direction of the calibration display portion may be formed at the center of the calibration display portion. And, a floating member slid along the guide groove may be installed in the guide groove. Since the floating member precisely informs the level of the fragrant material, the user can more easily check the remaining amount of the fragrant material.
[0047] FIG. 4 is a perspective view of a clothes dryer having a liquid storage container according to a second embodiment of the present invention, which shows only the upper plate 10 of the clothes dryer.
[0048] A cut-out portion 12 is formed at a part of the upper plate 10 , and a reservoir 200 is fixed to a bottom surface of the cut-out portion 12 . Here, the reservoir 200 may be integrally formed with the upper plate 10 . The reservoir 200 has an opened upper surface, and a calibration display portion 210 is formed at one side of the reservoir 200 so as to be protruding from a bottom surface of the reservoir 200 . The calibration display portion 210 is integrally formed with the reservoir 200 . And, a calibration plate 212 having a plurality of calibrations thereon is attached onto an upper surface of the calibration display portion 210 . The calibration plate 212 is formed of a different material, or is formed to have a different color from the calibration display portion 210 . This may allow the user to more efficiently check the calibrations. It is also possible to directly form calibrations on the surface of the calibration display portion 210 without forming the calibration plate 212 .
[0049] A cover plate 220 formed of a transparent or semi-transparent material is mounted to the opened upper surface of the reservoir 200 . The cover plate 220 includes an orifice portion 222 and an opening 224 . The orifice portion 222 prevents liquid for supplementation from flowing to an upper surface of the cover plate 220 . A cover 230 is rotatably installed at one side of the cut-out portion 12 . And, the cover 230 includes a protrusion 232 having a shape corresponding to the orifice portion 222 , and a seal 234 for blocking the opening 224 . The opening can be easily opened just by opening the cover 230 including the sealing 234 .
[0050] In the preferred embodiment, the calibration display portion 210 is positioned below the calibration plate 212 . However, only the calibration plate 212 may be fixed to a side wall of the reservoir 200 without implementing the calibration display portion 210 . In this case, a spatial utilization degree of the inside of the reservoir 200 can be enhanced.
[0051] Referring to FIG. 6 , a reservoir 300 can be opened or closed by a cover 330 hinge-coupled to the cut-out portion 12 without implementing the cover plate. The reservoir 300 includes a calibration display portion 310 protruding from a bottom surface of the reservoir 300 , and a calibration plate 312 attached onto the calibration display portion 310 .
[0052] In the aforementioned embodiments, the calibration display portion serving as the level indicator is arranged so as to be inclined with respect to the upper surface of the reservoir, or the surface of the cover plate and the liquid. However, calibrations may be directly formed on an inner wall of the reservoir, which simplifies the structure of the reservoir. As the upper surface of the reservoir or the surface of the cover plate may be arranged so as to be inclined with respect to the liquid stored in the reservoir, the user's wide viewing angle may be obtained.
[0053] The foregoing embodiments and advantages are merely exemplary and to are not to be construed as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.
[0054] As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims. | Disclosed is a liquid storage container and a clothes dryer having the same. The liquid storage container comprises: a reservoir installed at the clothes dryer, and configured to store liquid therein; a light transmitting window disposed above the reservoir; and a level indicator configured to be partially or wholly immersed into the liquid stored in the reservoir according to a level of the liquid. According to the amount of the liquid stored in the reservoir, an immersed degree of the level indicator into the liquid may become different. Accordingly, a user may easily and rapidly check a remaining amount of the liquid with his or her naked eyes. | 3 |
This is a divisional of application Ser. No. 12/292,035 filed Nov. 10, 2008.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a light irradiating device for generating radiation from an LED light source, which enhances cell-mediated immunity. Also, the present invention is concerned with a method for enhancing cell-mediated immunity using the same.
2. Description of the Related Art
In humans, immunity, representative of the hallmarks of health, may be greatly weakened by excessive exercise, stress, and other factors.
An improvement in immunity allows the body to more easily surmount stress and to become healthy. In fact, immunopotentiation prevents the body from being infected with pathological microorganisms such as bacteria, fungi, viruses, etc. and, in the case of infection, helps the body overcome diseases and return to the healthy state.
Various studies have been done on the regional or systemic effects of visible light on the body, and thus far, lots of results have been reported concerning neonatal jaundice, improvement of microcirculation, promotion of wound healing, pain relief, control of circadian rhythms, etc.
For this reason, light therapy using visible light has recently become a new trend in natural medicine.
It was not until the late 1980s that light therapy attracted intensive attention thanks to the possibility of being a new alternative medicine. Since then, this medical field has made great progress. It is now widely known that light, whether natural or artificial, has a significant influence on one's usual states of feeling and of mind as well as physical and mental health. For instance, LLLT (low level light therapy) with low-frequency, narrow-band radiation has been proven helpful for pain relief and wound healing.
Studies on the relationship between visible light and immunity may be summarized as follows.
A division of immunity is characterized by the cells involved: humoral immunity is the aspect of immunity that is mediated by B-lymphocytes secreting antibodies such as immunoglobulins whereas the protection provided by cell mediated immunity involves T-lymphocytes acting most significantly.
Visible light has an influence on both of the divisions of immunity.
Irradiation with light in the wavelength range of UV elicits immune reactions mainly at the skin. Because UV light, short in wavelength, cannot penetrate the dermis layer, it mostly acts to suppress cell-mediated immunity at the skin.
On the other hand, visible light ranging in wavelength from 380 to 780 nm penetrates through the epidermis and the dermis to the vessels millimeters distant from the skin surface, so that it can be used to induce photoreactions in blood as well as the irradiated spot.
Samoilova et al. (2004) showed that visible light, unlike UV light, induces blood cells to experience structural and functional changes which are immediately transmitted to entire circulating blood pools through vessels.
Zhevago et al. (2004) reported that exposure to visible light alters immunoglobulin levels in blood with a sharp increase in the levels of IgM and IgA.
According to Kubasova et al. (1995), irradiation with a combination of low-energy density visible light and infrared light was observed to induce the formation of lymphoblasts.
Mach et al. (1999) focused on the effect of visible light on wound healing, reporting that T lymphocytes, responsible for cell-mediated immunity, play an important role in the visible light-induced wound healing.
Based on results from a histological examination on the skin exposed to 630 nm visible light for 8 hours, Takezaki et al. (2006) reported the gathering of T lymphocytes to the exposed skin region.
Visible radiations, although within the same wavelength range, differ from one another in properties depending on wavelength bands. In photodynamic therapy, in fact, visible light is used to potentiate or suppress immunity depending on the wavelengths thereof and the combined use of a sensitizer.
For reference, showing immunosuppressive properties, the UV light UVA or UVB is used for therapy for contact dermatitis or delayed hypersensitivity.
Taken together, results from previous studies indicate that the biological functions of light are determined by its wavelengths and irradiation energies.
Leading to the present, invention, intensive and thorough research into light therapy using visible light, conducted by the present inventors, resulted in the finding that visible light within a specific single wavelength band activates the structure of proteins involved in the activation of T lymphocytes responsible for cell-mediated immunity and that the visible light with the specific wavelength shows far higher immunopotentiation than typical visible light.
The visible light used in the present invention is quite different from the light used in conventional low level light therapy in terms of wavelength band, light coherency and energy density. Whereas the low level light therapy with low-frequency narrow-band light has an influence on the irradiated spot only, the light therapy using the light irradiating device of the present invention enhances cell-mediated immunity which is effected across the whole body.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a light irradiating device for irradiating and generating light in a specific wavelength band which activates the structure of proteins involved in the activation of T lymphocytes responsible for cell-mediated immunity thus effecting immunopotentiation, and a method for enhancing immunity using the same.
It is another object of the present invention to provide a light irradiating device for generating light in a specific wavelength band, which is so convenient for a user to carry that it can be used amidst daily life activities.
It is a further object of the present invention to provide a light irradiating device for generating light in a specific wavelength band, which can be used as a light source in a backlight unit or is applicable to various goods, such as a display, a cell phone, etc., thus enhancing immunity during the performance of daily life activities.
The above objects can be accomplished by a provision of a light irradiating device irradiating radiations which have a peak wavelength at 610±20 nm or 710±30 nm, radiant power of 0.01˜20 mW and a dose ranging in time (T)×light power density (P) from 0.5 mJ·cm −2 ˜5 J·cm −2 , thereby effecting immunopotentiation.
Preferably, the single wavelength of the radiations has a peak at 610±5 nm, 710±5 nm and an radiant power of 0.1˜20 mW.
In the light irradiating device, LED, laser diode or OLED may be used as a light source as long as it generates a radiation with a peak wavelength at 610±20 nm or 710±30 nm. In this regard, a band pass filter may be provided for the light source so as to emit the radiation.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is an illustration of a light irradiating device in accordance with an embodiment of the present invention;
FIG. 2 is a spectrum of light with a wavelength band of 610±20 nm;
FIG. 3 is a spectrum of light with a wavelength band of 710±30 nm;
FIG. 4 is a view showing agarose gels on which PCR products from light-exposed or non-exposed rats are separated and stained with ethidium bromide;
FIG. 5 is a graph showing FACS results of CD4+ T lymphocytes and CD8+ T lymphocytes before exposure to the light;
FIG. 6 is a graph showing FACS results of CD4+ T lymphocytes and CD8+ T lymphocytes after-exposure to the light;
FIG. 7 shows representative flow cytometry of the experimental groups after exposure to the light.
FIG. 8 is a graph showing FACS results of CD4+ T lymphocytes and CD8+ T lymphocytes after the experimental group is exposed to the light and then not exposed for 5 weeks;
FIG. 9 is an illustrative view showing the application of the light irradiating device to a display monitor;
FIG. 10 is spectra of radiation emitted from a typical LCD monitor; and
FIG. 11 is spectra of radiation emitted from a typical cell phone.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference now should be made to the drawings to describe the present invention in detail.
FIG. 1 is an illustration of a light irradiating device in accordance with an embodiment of the present invention. This light irradiation device comprises a body 10 housing an LED light source 20 , designed to irradiate one of single wavelength-band rays with peaks of 610±20 nm and 710±30 nm.
The body 10 may be cylindrical and may be provided at one end thereof with a bandpass filter through which the light generated from the LED 20 passes to have a peak wavelength of 610±20 nm or 710±30 nm.
With reference to FIGS. 2 and 3 , there are spectra of the light irradiated from the light irradiating device of the present invention that are 610±20 nm and 710±30 nm in peak wavelength, respectively.
In accordance with an embodiment of the present invention, the body 10 may be provided with a controller for maintaining the emitted light from the LED 20 at such a wavelength band as to have a peak wavelength of 610±20 nm or 710±30 nm and to be of a predetermined light intensity.
The light emitted from the LED 20 ranges in radiant power from 0.01 to 20 mW.
An experimental result obtained in the development of the present invention indicates that when the light energy of the light emitted from the light irradiating device falls within the range 0.5 mJ·cm −2 <T×P<5 J·cm −2 wherein T is time of single radiation dose and P is light power density, desirable immunopentiation is obtained.
In order for the light irradiating device of the present invention to have an influence on the immune system, an exposure time of at least 10 μs is required when the emitted light has a light radiant power of 0.01˜20 mW and a light power density of 5 μW·cm −2 ˜5 kW·cm −2 .
The light irradiating device of the present invention was examined for effects on immunity through the following experiments conducted by the present inventors.
A better understanding of the present invention may be obtained through the following examples which are set forth to illustrate, but are not to be construed as limiting the present invention.
[Animals and Animal Handling]
35 male, specific pathogen-free Sprague-Dawley rats in their 8 th week of life were bred in a controlled room at 22° C. with a 12-hour light/dark cycle by turning on and off fluorescent lamps and allowed to freely approach water and feedstuff. The experimental animals were handled at the Institute of Biomedical Science and Technology in Konkuk University, Korea, and the experimental protocols were approved by the Institutional Animal Care and Use Committee of Konkuk University.
[Light Irradiating Devices Used in Experiments]
Used were Device A for irradiating light with a peak wavelength of 540 nm, Device B for irradiating light with a peak wavelength of 610 nm, and Device C for irradiating light with a peak wavelength of 710 nm.
Three of the devices were fabricated directly by the present inventors and employed LED light sources and irradiated light with a radiant power of 0.047 mW.
[Irradiation]
The experimental rates were divided into four groups: five exposed to the 540 nm light from Device A; eleven exposed to the 610 nm light from Device B; eleven exposed to 710 nm light from Device C; and eight as a non-exposed control.
While eight control rats were under the fluorescent lamps of the breeding room during the 12 hour light cycle, the experimental groups were irradiated with the light of 540 nm, 610 nm and 710 nm wavelengths from Devices A, B and C, respectively for the same time period.
This procedure was continuously repeated for 28 days.
EXPERIMENTAL EXAMPLE 1
RT-PCR
Total RNA was isolated from 1 ml of whole blood sampled from tail veins of the experimental rats using QiaAmp RNA blood mini (Qiagen GmbH, Hilden, Germany) according to the instructions of the manufacturer.
2 μg of mRNA was used for reverse transcription with Superscript II (Invitrogen, Branfort, Conn., USA). 2 μl of the cDNA thus obtained was amplified by PCR.
PCR primers for IL-1β, IL-4, IL-6 and IFNγ are listed in Table 1, below.
TABLE 1
Product
Target
Direc-
sizes
genes
tions
Sequences
(bp)
IL-1β
Sense
5′-CTGTCCTGATGAGAGCATCC-3′
330
Reverse
5′-TGTCCATTGAGGTGGAGAGC-3′
IFNγ
Sense
5′-GCTGTTACTGCCAAGGCACA-3′
400
Reverse
5′-CGACTCCTTTTCCGCTTCCT-3′
IL-4
Sense
5′-GAGCTATTGATGGGTCTCAGC-3′
400
Reverse
5′-GGCTTTCCAGGAAGTCTTTCA-3′
IL-6
Sense
5′-ACAAGTCCGGAGAGGAGACT-3′
490
Reverse
5′-GGATGGTCTTGGTCCTTAGC-3′
After initiation with denaturing at 94° C. for 2 min, PCR was performed with 30 cycles of denaturing at 94° C. for 20 sec, annealing at 58° C. for 40 sec and extension at 72° C. for 1 min.
The PCR products thus obtained were identified by separation on 1% agarose gel.
EXPERIMENTAL EXAMPLE 2
Flow Cytometry
From 1.5 ml of blood samples from the rats, monocytes were isolated with the aid of Ficoll-paque (Amersham Bioscience, Uppsala, Sweden).
Cells were placed at a density of 5×10 5 cells per test tube into test tubes and treated on ice for 1 hour with 0.25 μg of a PE-conjugated anti-rat-CD4 antibody (BD Bioscience Pharmigen, Cambridge, U.K) or a PE-conjugated anti-rat-CD8a antibody (BD Bioscience Pharmigen, Cambridge, U.K), followed by washing twice with phosphate buffered saline (PBS) and 5% fetal bovine serum.
The cells were measured for fluorescence using a flow cytometer (FACS Calibur, Beckton-Dickinson, Mountain View, Calif., USA) and analyzed using a cell Quest Pro program (Beckton-Dickinson, Mountain View, Calif., USA).
[Results of RT-PCR for Cytokines]
With reference to FIG. 4 , PCR products obtained in Experimental Example 1 are visualized with ethidium bromide on agarose gel.
As seen in this figure, the experimental groups exposed to 610 nm or 710 nm light were found to increase in IL-4 mRNA level in comparison with the control, but not detected for IFNγ.
An increase in the mRNA level of IL-1β and IL-6 was observed from the 710 nm Group, but with no statistical significance.
No differences were found between the 540 nm Group and the control with regard to the expression levels of IL-4, IL-6 and IFNγ.
Thus, flow cytometry analysis was conducted only on the 610 nm Group, the 710 nm Group and the control as follows.
[Results of Flow Cytometry Analysis for CD4 + /CD8 + T Lymphocytes]
Along with the control, the 610 nm Group and the 710 nm Group were analyzed for the distribution of CD4+ and CD8+ T lymphocytes using FACS. % distribution of CD4+ T lymphocytes in the 710 nm Group was increased with a statistical significance (p<0.05)), but neither the control nor the 610 nm Group was observed to increase in the % distribution (see FIGS. 5 and 6 ).
In FIGS. 5 and 6 , the difference between the experimental groups was obtained using the one-way ANOVA and the bonferroni procedure.
Significant difference for the distribution of CD8+ was detected in none of the groups.
FIG. 7 shows representative flow cytometry of the experimental groups after exposure to the light.
When, after exposure to the light for four weeks (28 days), the 710 nm Group was not irradiated with the light for five weeks, as in the control, the light-induced CD4+ T lymphocyte increase was not detected, but the level was returned back to the control (see FIG. 8 ).
The results from the flow cytometric analysis indicate that light with a peak wavelength of 710 nm induced the proliferation of CD4+ helper T lymphocytes.
Also, the results from the RT-PCR analysis show that the LED radiation with a peak wavelength of 710 nm increases the level of IL-4 mRNA, which is produced mainly in CD4+ helper T lymphocytes, supporting the results of the flow cytometry.
In spite of its effective ability to proliferate CD4+ T lymphocytes, the LED radiation with a peak wavelength of 710 nm was found to have no influence on the synthesis of the cytokines IL-1β and IL-6, which are potential inducers of acute phase reactant proteins acting as inflammation indices.
Also, the LED radiation with a peak wavelength of 610 nm was found to activate CD4+ helper T cells by increasing IL-4 mRNA levels, as analyzed on DNA level by RT-PCR.
Accordingly, it is expected that, when illuminated on the body, radiations with peaks at 610 nm±20 nm and at 710±30 nm are useful in immunopoentiation and that the light irradiating device of the present invention may be installed in various goods.
For example, when used as a light source for indoor lamps of rooms and vehicles, for instrument panels of vehicles, etc., the light irradiating device of the present invention is expected to irradiate the body with radiations which are highly effective in immunopotentiation without interference with daily life activities.
When equipped with a mounting means 30 , the light irradiating device of the present invention finds a further broad range of applications including neighboring structures (computer monitors, electronic appliances, desks, etc.).
Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. | Disclosed are a light irradiating device for enhancing cell-mediated immunity and a method using the same. The light irradiating device generates a radiation with a specific peak wavelength at 610±20 nm or 710±30 nm which activates the structure of proteins involved in the activation of T lymphocytes responsible for cell-mediated immunity thus effecting immunopotentiation. | 0 |
BACKGROUND
1. Field of Invention
The inventions described herein relate in general to circuits for controlling an output current of a Rambus DRAM. More particularly, they relate to an output current control circuit enabling reduction of circuit area and current consumption compared with known devices.
2. General Background and Related Art
FIG. 1 (Prior Art) is a block diagram of a known circuit arrangement for controlling output driving of a Rambus DRAM. An output current controller 10 produces a current control signal ictrl <0:6> that controls a current flow of an output driver by increasing or decreasing a current control counter. This is accomplished by measuring actual voltage levels VOH and VOL from a data port DQA. A gate voltage generator, VTG GNR 11 produces a gate voltage Vgate as a new voltage level. A gate voltage distributor 12 provides an upper device of the output driver with a voltage envg <0:6> attained by multiplexing a time clock enabling signal tclk enable and the current control signal ictrl <0:6> generated from voltage generator 11 in accordance with the gate voltage Vgate generated from voltage generator 11 . A slew-rate controller 13 produces control codes sl 1 and sl 2 specifying a slew rate of an output regardless of power, voltage, and temperature. A phase splitter 14 generates clocks tclk 1 and tclk 1 b having 180° difference from one another and based on an input time clock tclk. A MUX/predriver 15 outputs input data eread and oread, which are synchronized with the clocks tclk 1 and tclk 1 b output from the phase splitter 14 , to an output driver 16 in the form of voltages q and q 1 to output driver 16 , constituting a lower device of the output driver in accordance with the control codes sl 1 and sl 2 provided by the slew rate controller 13 . Output driver 16 provides a pad PAD with a an appropriate current by providing a pull-down path of a Rambus signal logic(RSL) by turning on/off N-type MOS transistors in accordance with the voltage envg<0:6> distributed by the gate voltage distributor 12 and the voltages q and q 1 output from the MUX/predriver 15 .
In the output current controller 10 at an initial stage of active operation, actual current levels are measured from a pair of input pads DQA<4> and DQA<3>(not shown in the drawing) respectively. A count value is then decreased the output current control counter if the measured current levels are higher than a specific value, or the count value is then increased if the measured current levels are lower than the specific value. Thus, the output current controller 10 outputs the output current control signal ictrl<0:6>, which adjusts the number of turned-on transistors of the output driver 16 so as to satisfy an output current flow of the output driver 16 , to the gate voltage distributor 12 .
A time clock enabling signal tclk enable is input to the gate voltage distributor 12 from an external input. In this case, the gate voltage generator 11 provides the gate voltage distributor 12 with a gate voltage Vgate which is a voltage having a new level as a source power. Ultimately, the gate voltage distributor 12 receives the output current control signal ictrl <0:6> output from the output current controller 10 , the time clock enabling signal tclk enable, and the gate voltage Vgate output from the voltage generator 11 . The gate voltage distributor 12 multiplexes the current control signal ictrl <0:6> and time clock enabling signal tclk enable received by the output current controller 10 , selects and outputs the gate voltage Vgate or a ground voltage VSS enabling to adjust the turning-on number in accordance with the multiplexed value, and then outputs it to the output driver 16 .
FIG. 2 (Prior Art) is a schematic diagram including detailed circuits of the gate voltage distributor 12 and the output driver 16 shown in FIG. 1 (Prior Art). A Vgate voltage as a new voltage, which is produced by carrying out comparison and amplification on a reference voltage Vgref input to an inverting input (−) of an operational amplifier OP 1 and a voltage input to a non-inverting input terminal (+) by being fed back from an output terminal, is output to an inverter I 1 . In this case, a NAND gate ND 1 carries out a NAND operation on the current control signal ictrl <0:6> output from the current controller 10 and the time clock enabling signal tclk_enable and then provides the inverter I 1 with them. The inverter I 1 then inverts the output signal from NAND gate ND 1 in a manner that the output driver 16 is provided with the gate enabling signal envg <0:6> having a gate voltage level using the gate voltage Vgate output from amplifier OP 1 as a source if the signal output from the NAND gate ND 1 is low or the gate enabling signal envg <0:6> having a ground voltage level using the ground voltage VSS as a source if the signal output from the NAND gate ND 1 is high. Therefore, lower transistors Tr 1 to Trn of the output driver 16 are turned on as many as the number of the gate enabling signals envg having the gate voltage level output from the inverter I 1 .
Receiving a time clock tclk form outside, the phase splitter 14 produces a pair of clocks tclk 1 and tclkb having a 180° phase difference (see FIG. 1) and then provides the MUX/predriver 15 with the clocks tclk 1 and tclkb. Even and odd data are input to the MUX/predriver 15 from outside. The slew-rate controller 13 (see FIG. 1) outputs the control codes sl 1 and sl 2 to the MUX/predriver 15 so as to fix a slew rate of an output regardless of power, voltage, and temperature. Therefore, the MUX/predriver 15 transmits the even data to the output driver 16 if receiving the clock tclk 1 from the phase splitter 14 or the odd data to the output driver 16 if receiving the other clock tclk 1 b having a different phase (180° from tclk 1 ).
Receiving the control codes sl 1 and sl 2 (shown in FIG. 1) from the slew-rate controller 13 , the MUX/predriver 15 outputs the control voltages q and q 1 to the output driver 16 so as to turn on/off the lower device of the output driver 16 such as the lower transistors. Transistors Tr 1 to Trn as the upper device of the output driver 16 are turned on as many as the number adjusted by the output voltage envg <0:6> of the gate voltage distributor 12 , while the other transistors T 1 to Tn and Q 1 to Qn as the lower device of the output driver 12 are turned on by the MUX/predriver 15 so as to form a pull-down path.
Capacitors ‘C 1 ’ and ‘C 2 ’ of the output driver 16 are decoupling capacitors preventing noise coupling. The upper and lower transistors become turned on so as to supply the corresponding pad with a satisfactory output current by adjusting an output of RSL (Rambus signaling level), that is a swing width, and carry output data on a channel.
Generally, a command, so-called current control, is carried out periodically in a Rambus DRAM so as to maintain a constant output current at a data port. The data port in Rambus DRAM is constructed with 8 bit buses DQA[7:0] and DQB[7:0] (not shown in FIG. 2 ). A known output current control circuit for controlling currents output from the data ports DQA[7:0] and DQB[7:0] constantly is explained by referring to FIG. 3 as follows.
FIG. 3 is a block diagram of the output current controller 10 shown in FIG. 1 . An enabling signal CCEval becomes active (‘high’ when a ‘current control command’ is applied to a Rambus DRAM from a controller (not shown in the drawing). The output current controller 10 includes a first current detector 31 outputting a signal CClncrA having a ‘low’ value if a current flow received from a couple of the data ports (not shown in the drawing) DQA<4> and DQA<3> by the enabling signal CCEval is higher than a target value through a comparison therebetween or a signal CClncrA having a ‘high’ value if the current flow is lower than the target value. A first output current control counter 32 produces a signal cvalA_pre<6:0> of which control value of 7 bits is incremented by 1 than the currently-output current control signal ictrla<6:0> if the signal CClncrA received from the first current detector 31 or a signal cvalA_pre<6:0> of which control value of 7 bits is decremented by 1 than the currently-output current control signal if the signal CClncrA has a ‘low’ value. A first output current latch counter 33 latches the signal cvalA_pre<6:0> received from the first output current control counter 32 when a received control signal ccUpdata becomes active (‘high’) and produces the latched signal as the current control signal ictrla<6:0>.
Moreover, the output current controller 10 includes a second current detector 41 outputting a signal CClncrB having a ‘low’ value if a current flow received from a couple of the data ports (not shown in the drawing) DQA<4> and DQA<3> by the enabling signal CCEval is higher than a target value through a comparison therebetween or a signal CClncrB having a ‘high’ value if the current flow is lower than the target value, a second output current control counter 42 produces a signal cvalB_pre<6:0> of which control value of 7 bits is incremented by 1 than the currently-output current control signal ictrla<6:0> if the signal CClncrB received from the second current detector 41 or a signal cvalB_pre<6:0> of which control value of 7 bits is decremented by 1 than the currently-output current control signal if the signal CClncrB has a ‘low’ value, and a second output current latch counter 43 latching the signal cvalB_pre<6:0> received from the second output current control counter 42 when a received control signal ccUpdate becomes active(‘high’) and produces the latched signal as the current control signal ictrlb<6:0>.
The operation of output current controller 10 shown in FIGS. 1 and 3 (Prior Art) is explained by referring to an operational timing graph shown in FIG. 4 (Prior Art). The enabling signal CCEval becomes active as ‘high’ when the ‘current control command’ is applied to Rambus DRAM from the controller (not shown in the drawing). The first and second current detectors 31 and 41 controlled by the enabling signal CCEval are operated respectively so as to compare the current flow received from the two data ports DQA<3> and DQA<4> to the target vale. In this case, the signals CClncrA and CClncrB having ‘low’ values are output if the current flow received from the data ports DQA<4>/DQA<3> and DQB<4>/DQB<3> is higher than the target value so as to reduce a current flow output to the present data ports. If the current flow received from the data ports DQA<4>/DQA<3> and DQB<4>/DQB<3> is lower than the target value, the signals having ‘high’ values are output so as to increase the current flow output to the present data ports.
Subsequently, the first and second output current control counters 32 and 42 , if the signals received respectively from the first and second current detectors 31 and 41 have ‘high’ values, produce the signals cvalA_pre<6:0> and cvalB_pre<6:0> of which control values of 7 bits are incremented by 1 than the currently-output current control signals ictrla<6:0> and ictrlb<6:0>. And, if the signals received respectively from the first and second current detectors 31 and 41 have ‘low’ values, the first and second output current control counters 32 and 42 produce the signals cvalA_pre<6:0> and cvalB_pre<6:0> of which control values of 7 bits are decremented by 1 than the currently-output current control signals ictrla<6:0> and ictrlb<6:0>.
The first and second output current latch counters 33 and 43 , when the control signal ccUpdate is on a active state(‘high’), latch the signals cvalA_pre<6:0> and cvalB_pre<6:0> received from the first and second output current control counters 32 and 42 so as to produce the current control signals ictrla<6:0> and ictrlb<6:0>.
Therefore, the output current controller 10 according to the related art increases or decreases the output current control counters by measuring actual current values from the two data ports DQA[7:0] and DQB 7 :[7:0], thereby enabling to control a current flow of the output driver 16 .
Unfortunately, the output current controller 10 includes the first and second output current control counters 32 and 42 having the same function and construction for increasing or decreasing the control values of 7 bits using the signals CClncrA and CClncrB received from the first and second current detectors 31 and 41 , which increases circuit area and power consumption.
SUMMARY
Among the inventions described in this patent document, there is detailed a circuit for controlling an output current in a Rambus DRAM that substantially obviates the disadvantages of the known circuit arrangements.
Provided herein are circuit arrangements that control an output current in a Rambus DRAM using less circuit area and current consumption compared with the known arrangements. This is accomplished in part by using a single output current control counter instead of a pair of first and second output current controllers 32 and 42 as in the known arrangements. Our arrangements also control the current of data ports DQA and DQB using multiplexing.
Additional features and advantages of the invention will become evident by reading the detailed description below in conjunction with the accompanying drawings.
Among the inventions described herein there is provided a circuit for controlling output currents of the data ports in a Rambus DRAM having two data ports DQA and DQB. First and second current evaluation means output first and second control signals respectively by evaluating currents of the data ports DQA and DQB. A current control value producing means produces a next current control value for the data port DQA by receiving the first control signal and a present current control value of the data port DQA and produces a next current control value for the data port DQB by receiving the second control signal and a present current control value of the data port DQB. The current control value producing means repeats the process to produce the next current control values alternately. First and second control value latch means latch the respective current control values of the data ports DQA and DQB produced by the current control value producing means.
According to another aspect of the inventions, there is provided a circuit for controlling output current in a Rambus DRAM, which is operated by responding to an enabling signal becoming active when a ‘current control command’ is applied to the Rambus DRAM from a controller. A first current detector produces a detection signal attained by comparing current flows received from first and second terminals of a first data port by the enabling signal to a predetermined target value. A second current detector produces a detection signal attained by comparing current flows received from first and second terminals of a second data port by the enabling signal to a predetermined target value. A first multiplexer selects one of the signals received from the first and second current detectors by a first control signal and outputs the selected signal. A second multiplexer selects one of first and second output current control signals by the first control signal and outputs the selected output current control signal. An output current control counter produces a signal incremented or decremented by ‘1 bit’ from the signal received from the second multiplexer by the signal received from the first multiplexer. A first output current latch counter latches the signal received from the output current control counter by a second control signal and produces the latched signal as the first output current control signal. A second output current latch counter latches the signal received from the output current control counter by a third control signal and produces the latched signal as the second output current control signal.
The output current control circuit does not need to have the dedicated output current control counters for each of data ports DQA and DQB, as in known arrangements. Instead, the output current control circuit includes only one output current control counter, and generates output current control signals alternately for data ports DQA and DQB by using multiplexing technique. Therefore, it is possible to eliminate the redundancy, while the whole circuit performs the same operation. Although the present invention requires two additional multiplexers for performing multiplexing the related signals of the two data port DQA and DQB, the present invention is effective in reducing the chip area (compared with known arrangements) which is necessary to implement the entire circuit. That is because the area of one output current counter is much larger than that of two multipliers. The arrangements taught herein are effective in reducing the power consumption which is necessary to drive the circuit.
The foregoing general description and the following detailed description 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 specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings:
FIG. 1 (Prior Art) is a block diagram of a known circuit arrangement for controlling output driving of a Rambus DRAM;
FIG. 2 (Prior Art) is a detailed circuit diagram of the gate voltage distributor and the output driver shown in FIG. 1 (Prior Art);
FIG. 3 (Prior Art) is a block diagram of the output current controller shown in FIG. 1 (Prior Art);
FIG. 4 (Prior Art) is a timing diagram explaining the operation of the output current controller shown in FIG. 2 (Prior Art);
FIG. 5 is a block diagram of a circuit for controlling an output current in a Rambus DRAM according to the present invention;
FIG. 6 A and FIG. 6B are schematic circuit diagrams of the first and second multiplexers, respectively shown in FIG. 5;
FIG. 7 is a schematic diagram of a control signal producing circuit for producing control signals of the first and second multiplexers shown in FIG. 5 and FIG. 6; and
FIG. 8 is a timing diagram explaining operation of the output current controller shown in FIG. 5 .
DETAILED DESCRIPTION
Non-limiting presently preferred embodiments of the inventions will be explained in detail to enable practicing the inventions claimed herein. This description should be taken in conjuction with the drawings, together constituting the explanation of the inventions. Where possible, the same reference numerals are used to illustrate like elements throughout the specification.
It is intended to provide an explanation of a circuit for controlling an output current of data ports in a Rambus DRAM having data ports DQA and DQB.
FIG. 5 is a block diagram of a circuit for controlling output current of a Rambus DRAM according to the present invention. An enabling signal CCEval becomes active(‘high’ when a ‘current control command’ is applied to a Rambus DRAM from a controller (not shown in the drawing). An output current controller according to the present invention includes a first current detector 110 outputting a signal CClncrA having a ‘low’ value if a current flow received from a pair of data ports (not shown in the drawing) DQA<4> and DQA<3> by the enabling signal CCEval is higher than a target value by a comparison therebetween or a signal CClncrA having a ‘high’ value if the current flow is lower than the target value. A second current detector 120 outputs a signal CClncrB having a ‘low’ value if a current flow received from a pair of data ports (not shown in the drawing) DQA<4> and DQA<3> by the enabling signal CCEval is higher than a target value by comparison therebetween or a signal CClncrB having a ‘high’ value if the current flow is lower than the target value. A first multiplexer 130 selects to output the signals CClncrA and CClncrB received from the first and second current detectors 110 and 120 responsive to a control signal Select. A second multiplexer 150 receives the output current control signals ictrla<6:0> and ictrlb<6:0> output and selects to output the signals responsive to the control signal Select. An output current control counter 140 produces a signal Cval_pre<6:0> of which bits are incremented/decremented by 1 from the signal ictrla<6:0> or ictrlb<6:0> received from the second multiplexer 150 by the signal CClncrA or CClncrB received from the first multiplexer 130 . A first output current latch counter 160 latches the signal cvalA_pre<6:0> received from the output current control counter 140 when a first control signal ccUpdateA becomes active(‘high’) and produces the latched signal as the current control signal ictrla<6:0>, and a second output current latch counter 170 latches the signal cvalB_pre<6:0> received from the second output current control counter 140 when the received control signal ccUpdateB becomes active(‘high’) and produces the latched signal as the current control signal ictrlb<6:0>.
The enabling signal CCEval becomes active as ‘high’ when the ‘current control command’ is applied to Rambus DRAM from the controller (not shown in the drawing). The first and second current detectors 110 and 120 compare the current flow received from the two data ports DQA<4>/DQA<3> and DQB<4>/DQB<3> to the target vale. In this case, the signals CClncrA and CClncrB having ‘low’ values are output if the current flow received from the data ports DQA<4>/DQA<3> and DQB<4>/DQB<3> is higher than the target value so as to reduce a current flow output to the present data ports. If the current flow received from the data ports DQA<4>/DQA<3> and DQB<4>/DQB<3> is lower than the target value, the signals having ‘high’ values are output so as to increase the current flow output to the present data ports.
The first multiplexer 130 selects the signal CClncrA or CClncrB received from the first and second current detectors 110 and 120 by the control signal Select and outputs the selected signal to the output current control counter 140 . In this case, the first multiplexer 130 controls the control signal(‘low’) so as to output the signal CClncrA received from the first current detector 110 on an initial operation.
FIG. 6A is a schematic circuit diagram of the first multiplexer 130 shown in FIG. 5 . The first multiplexer 130 is constructed with a transfer gate 132 transmitting the signal CClncrA received from the first current detector 110 (see FIG. 5) to the output current control counter 140 (see FIG. 5) responsive to the control signal Select. Another transfer gate 133 transmits the signal CClncrB received from the second current detector 120 (see FIG. 5) to the output current control counter 140 (see FIG. 5) responsive to the control signal Select. Transfer gates 132 and 133 , which are constructed with PMOS and NMOS transistors, are operated oppositely by the control signal Select and inverter 131 .
FIG. 6B is a schematic circuit diagram of the second multiplexers 150 shown in FIG. 5 . The second multiplexer 150 receives the output current control signals ictrla<6:0> and ictrlb<6:0> output from the first and second output current latch counters 160 and 170 and then outputs the signal selected by the control signal Select to the output current control counter 140 . In this case, the second multiplexer 150 controls the control signal Select(‘low’) so that the output current control signal ictrlas<6:0> received from the first output current latch counter 160 is output therefrom on an initial operation.
The second multiplexer 150 is constructed with a transfer gate 152 transmitting the signal ictrla<6:0> received from the first output current latch counter 160 to the output current control counter 140 by the control signal Select and another transfer gate 153 transmitting the signal ictrlb<6:0> received from the second output current latch counter 170 to the output current control counter 140 responsive to the control signal Select. The transfer gates 152 and 153 , which are constructed with PMOS and NMOS transistors, are operated oppositely by the control signal Select and inverter 151 .
The output current control counter 140 , when the signal CClncrA or CClncrb received from the first multiplexer 130 has a ‘high’ value, produces a signal Cval_pre<6:0> which is incremented by 1 bit from the signal ictrla<6:0> or ictrlb<6:0> received from the second multiplexer 150 . And, the output current controller 140 , when the signal CClncrA or CClncrb received from the first multiplexer 130 has a ‘low’ value, produces a signal Cval_pre<6:0> which is decremented by 1 bit from the signal ictrla<6:0> or ictrlb<6:0> received from the second multiplexer 150 .
The first output current latch counter 160 latches the signal Cval_pre<6:0> received from the output current control counter 140 when the control signal ccUpdateA becomes active(‘high’) and producing the latched signal as the current control signal ictrla<6:0>.
The second output current latch counter 170 latches the signal Cval_pre<6:0> received from the second output current control counter 140 when the received control signal ccUpdateB becomes active (‘high’) and producing the latched signal as the current control signal ictrlb<6:0>.
FIG. 7 is a schematic circuit diagram of a control signal producing circuit for producing control signals of the first and second multiplexers 130 and 150 shown in FIG. 5 and in FIGS. 6A and 6B, respectively.
An OR gate 201 receives the control signal ccUpdateB for updating the output current control signal ictrlb<6:0> toward the data port DQB and a reset signal as two inputs. A latch circuit 202 produces the control signal Select for the first and second multiplexers 130 and 150 by utilizing the signal from OR gate 201 as a reset signal RST. The control signal ccUpdateA updates the output current control signal ictrla<6:0> at the other data port DQA as an enabling signal EN. A power source voltage Vcc is input to the D port of latch circuit 202 .
The control signal Select as the output signal of the latch circuit 202 is changed from ‘0(low)’ to ‘1’ as soon as the control signal ccUpdateA is changed into ‘1 (high)’. When the control signal ccUpdateB becomes ‘1’, the latch circuit 202 resets. Thus, the control signal Select becomes initialized to ‘0’ again.
Operation of the output current control circuit, as described above, is explained by referring to the attached drawings as follows.
A Rambus DRAM carries out a ‘current control command’ periodically(about 100 ms) so as to maintain a constant output current(about 30 mA) from the data ports DQA and DQB. Such an operation is carried out in a manner that a memory controller (not shown in the drawing) applies the current control command to the Rambus DRAM periodically from outside. When the memory controller applies the current control command to the Rambus DRAM, the current control enabling signal CCEval becomes active as ‘high’. Once the current control enabling signal CCEval becomes ‘high’, the first and second current detectors 110 and 120 detecting currents of the data ports DQA and DQB respectively measure the present current flow with the voltage states of the data ports DQA<4>/DQA<3> and DQB<4>/DQB<3>. If the present current flow is less than the target value(about 30 mA), the detection signals CClncrA and CClncrB from the first and second current detectors 110 and 120 become ‘1’. If the present current flow is larger than the target value(about 30 mA), the detection signals CClncrA and CClncrB from the first and second current detectors 110 and 120 become ‘0’.
Meanwhile, the data port DQA is completely separated from the other data port DQB, whereby current flows of the data ports DQA and DQB may be different from each other. Thus, the detection signals CClncrA and CClncrB output from the first and second current detectors 110 and 120 may differ in values. When the detection signals CClncrA and CClncrB output from the first and second current detectors 110 and 120 are ‘1(high)’, the output current control signals ictrla<6:0> and ictrla<6:0> controlling currents are increased since the present current flow is less than the target flow. On the other hand, when the detection signals CClncrA and CClncrB output from the first and second current detectors 110 and 120 are ‘0(low)’, the output current control signals ictrla<6:0> and ictrla<6:0> controlling currents are decreased since the present current flow is larger than the target flow.
As shown in FIG. 5, the output current control counter 140 , which increments or decrements the output current control signals ictrla<6:0> and ictrlb<6:0> controlling the currents of the respective data ports DQA and DQB one by one in accordance with the detection signals CClncrA and CClncrB, is singly constructed in the present invention, a significant savings in circuit ‘real estate’ from the known circuit arrangements. Also, the output current control counter 140 is constructed with the first and second multiplexers 130 and 150 so that the output currents of the data ports DQA and DQB are multiplexed by the control signal Select.
By setting the control signal Select as ‘0’ in the initial stage, the operation of the first and second multiplexers 130 and 150 are controlled such that the output current control counter 140 receives the detection signal CClncrA output from the first detector 110 and the signal ictrla<6:0> output from the first output current latch counter 160 .
The output current control counter 140 outputs the signal Cval_pre<6:0>, which is attained by incrementing(when CClncrA =‘1’) or decrementing (when CClncrA =‘0’) the present value of the output current control signal ictrla<6:0> received from the first output current latch counter 160 by ‘1’ in accordance with the value of the detection signal CClncrA, to the first and second output current latch counter parts 160 and 170 .
The first output current latch counter 160 latches the signal Cval_pre<6:0> received from the output current control counter 140 and updates the output current control signal ictrla<6:0> as an output signal as soon as the control signal ccUpdateA is changed into ‘1’. In this case, the second output current latch counter 170 fails to operate.
As shown in FIG. 7, the control signal Select changes from ‘0’ to ‘1’ the moment the control signal ccUpdateA for updating the output current control signal ictrla toward the data port DQA is changed into ‘1’. Thus, the detection signal CClncrB output from the second current detector 120 is transferred to the output current control counter 140 through the first multiplexer 130 , and the output current control signal ictrlb<6:0> output from the second output current latch counter 170 is transferred to the output current control counter 140 through the second multiplexer 150 . Therefore, the output current control counter 140 increments or decrements the value of the output current control signal ictrlb<6:0> output from the second output current latch counter 170 by 1 in accordance with the detection signal CClncrB output from the second current detector 120 and then outputs the incremented or decremented value. Subsequently, the second output control latch counter 170 latches the signal Cval_pre<6:0> received from the output current control latch 140 the moment the control signal ccUpdateB is changed into ‘1’, and updates the output current control signal ictrla<6:0> which is an output signal.
As shown in FIG. 7, when the control signal ccUpdateB becomes ‘1’, the latch circuit 202 is reset so as to initialize again the value of the control signal Select as ‘0’. This is for re-starting the updating though a path toward the data port DQA when the current control command is applied thereto again.
FIG. 8 is a timing diagram explaining operation of the output current controller shown in FIG. 5 . New control values of which values are incremented by 1 than the previous control values ictrla<6:0> and ictrlb<6:0> since the detection values CClncrA and CClncrB output from the first and second current detectors 110 and 120 are ‘1’. These new control values are transferred to a block (not shown in the drawing) so as to adjust a current flow.
As illustrated in the drawing, the output current control signal ictrla<6:0> output from the first output current latch counter 160 is firstly updated. The output current control signal ictrlb<6:0> output from the second output current latch counter 170 is then updated. Hence, the output current control circuit according to the present invention requires only one output current control counter 140 . Instead, the present invention uses the first and second multiplexers 130 and 150 such that the output currents of the data ports DQA and DQB are multiplexed by the control signal Select. In this case, the first and second multiplexers 130 and 150 are circuits occupying a very small area.
Therefore, the control circuit according to the present invention, compared with known circuit arrangements, require one less output current control counter, thereby reducing the required circuit area significantly and also reducing power consumption. Also, the time taken for updating both of the output current control signals ictrla<6:0> and ictrlb<6:0> in the output current control circuit of the present invention is equal to that of known circuit arrangements.
According to the above-mentioned present invention, the output current control circuit does not need to have the dedicated output current control counters for each of data ports DQA and DQB, as in the prior art. Instead of that, the output current control circuit includes only one output current control counter, and generates output current control signals alternately for data ports DQA and DQB by using multiplexing technique. Therefore, it is possible to eliminate the redundant part, while providing the same performance and saving power and circuit real estate. Although the present invention requires additional two multiplexers for performing multiplexing the related signals of the two data port DQA and DQB, the present invention is effective in reducing the chip area which is necessary to implement the entire circuit. That is because the area of one output current counter is much larger than that of two multipliers. And the present invention is effective in reducing the power consumption which is necessary to drive the circuit.
The foregoing embodiments are merely exemplary and are not to be construed as limiting the present invention. The present teachings can be readily applied to other types of apparatuses. The description of the present invention is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. | Disclosed is a circuit for controlling output currents of the data ports in a Rambus DRAM having two data ports DQA and DQB. The disclosed circuit arrangements save power and require less chip ‘real estate’ than do known circuit arrangements. First and second current evaluation means output first and second control signals respectively by evaluating currents of the data ports DQA and DQB. A current control value producing means produces a next current control value for the data port DQA by receiving the first control signal and a present current control value of the data port DQA and producing another next current control value for the data port DQB by receiving the second control signal and a present current control value of the data port DQB. The current control value producing means repeats the process to produce the next current control values alternately, and first and second control value latch means for latching the respective current control values of the data ports DQA and DQB produced by the current control value producing means. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates generally to a rear end for a racing car used in sprint racing, and, more particularly, to a rear end having offset drive gears for transferring rotational power from the engine to the rear axle of the racing car.
Sprint cars and smaller racing cars are powered by an engine supported in a frame and connected to a rear end gear box that transfers rotational power to the rear wheels of the racing car. The rear end gear box has a disconnect mechanism that interrupts the transmission of rotational power to the rear wheels. When the racing car is being operated on the race track, the rear end gear box is engaged to transfer power from the engine. When the operator desires to stop the movement of the racing car, the rear end gear box is operably disconnected from the engine so that rotational power is no longer being transferred.
In current state of the art racing car rear ends, the drive shaft connected between the engine and the rear end gear box transfers a substantial amount of power to the rear end. In some sprint cars, the engine can produce 950 horsepower to drive the racing car which may weigh only about 1300 pounds. The torque involved in the transfer of this much power, along with the external forces encountered during the racing of the sprint car, results in a movement of the drive shaft relative to the rear end. This slight “whipping” and vibrational movement of the drive shaft can place substantial wear on the bearings housed within the rear end. To minimize the wear problem, a swivel coupling has been adopted so that the swivel coupling can absorb the movement of the drive shaft without causing substantial wear problems.
The placement of a swivel coupling into the engine end of the rear end gear box causes spatial problems. Because of the ring gear contained within the rear end gear box to drive the rear axle of the racing car, the swivel coupling and a bearing for rotationally supporting the swivel coupling are located on the outside of the rear end housing. As a result, the bearing has to be a sealed bearing that contains its own lubricant, since the bearing is not in flow communication with the oil flow within the rear end housing. If the swivel coupling were located inside the conventional gear box, the interior portion of the swivel coupling would interfere with the ring gear. Accordingly, the swivel coupling is positioned outside the rear end housing where stability and rigidity of the swivel coupling is compromised. Furthermore, the swivel coupling is not lubricated from the oil within the rear end housing.
Sprint racing cars only turn to the left when racing around the track. Manufacturers have employed different strategies for shifting the center of gravity of the racing car to the left of the car centerline. One concept was to shift the engine to the left of the car centerline; however, the resulting coupling of the drive shaft between the engine and the rear end placed too much stress on the swivel coupler, reducing the life of the swivel coupler. Extending the life of the bearings and the swivel coupler is important to successful operation of the racing cars. If the swivel coupler or the bearings fail during a race, the race car is finished for the night.
Therefore, it would be desirable to provide a rear end structure for a racing car that would be operable to recess the swivel coupler and the associated bearing internal of the rear end housing so that the swivel coupler and the bearing would be lubricated by the oil within the rear end housing. It would also be desirable to provide a rear end structure for a racing car that results in a shifting of the center of gravity of the racing car to the left to increase the stability of the racing car while make turns on the race track.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a rear end gear box for a racing car in which the swivel coupling connecting the drive shaft from the engine to the rear end drive mechanism is mounted within the rear end housing.
It is another object of this invention to provide a rear end structure that shifts the center of gravity of the racing car to the left of the centerline of the car.
It is still another object of this invention to offset the drive shaft relative to the driven shaft within the rear end gear box structure.
It is a feature of this invention that the swivel coupler is supported internally of the rear end housing.
It is another feature of this invention that the bearing associated with supporting the swivel coupler is also mounted internally of the rear end housing.
It is an advantage of this invention that the swivel coupler and the bearing rotatably supporting the swivel coupler are lubricated by the oil within the rear end gear box housing.
It is another advantage of this invention that the supporting of the swivel coupler within the rear end housing increase the stability and the rigidity of the swivel coupler.
It is still another advantage of this invention that the operative life of the swivel coupler is increased by supporting the swivel coupler within the rear end gear box housing.
It is still another feature of this invention that the drive shaft is located in the rear end housing at an offset from a vertical plane extending through the center of the rear end housing in alignment with the driven shaft mounted within the rear end gear box housing.
It is yet another feature of this invention that the positioning of the drive shaft of the rear end gear box on the centerline of the racing car in alignment with the engine drive shaft places the center of gravity of the rear end structure to the left of the centerline of the racing car.
It is yet another advantage of this invention that rear end gear box shifts the center of gravity of the racing car to the left of the car centerline.
It is still another advantage of this invention that the rear end housing increases the stability of the racing car while turning around the race track.
It is still another feature of this invention that the cover over the transfer gears at the back end of the rear end gear box structure incorporates an O-ring to seal the cover against the rear end gear box housing.
It is still another advantage of this invention that the use of the O-ring allows for the cover to be closed quickly for a quick change of the transfer gears.
It is yet another object of this invention to provide a rear end gear box for a sprint racing car which is durable in construction, inexpensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective in use.
These and other objects, features and advantages are accomplished according to the instant invention by providing a rear end gear box for a racing car in which the swivel coupler and the bearing rotatably supporting the swivel coupler are mounted within the rear end housing so that oil within the rear end housing will lubricate the swivel coupler and its bearing. The input shaft delivering rotational power from the engine is offset to the right of the driven shaft within the rear end housing so that the center of gravity of the rear end is shifted to the left of the car centerline to increase stability of the car in turns. The recessed swivel coupler has an extended operating life due to increase stability and rigidity provided by the support from the housing structure. The cover for the back end of the rear end structure where the transfer gears are located is provided with an O-ring to facilitate a quick change of the transfer gears.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages of this invention will be apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein:
FIG. 1 is a side elevational view of a rear end gear box housing incorporating the principles of the instant invention, the front or engine end of the rear end gear box being to the right side of the figure and the back end on the left side, the movement of the external shift lever being depicted in phantom;
FIG. 2 is a top plan view of the rear end gear box housing depicted in FIG. 1 ;
FIG. 3 is an end elevational view of the engine end of the rear end gear box housing shown in FIGS. 1 and 2 ;
FIG. 4 is a end elevational view of the back end of the rear end gear box housing opposite to the view of FIG. 3 ;
FIG. 5 is a cross sectional view through the rear end gear box taken along lines 5 - 5 of FIG. 3 , the drive components being depicted for transferring the rotational power from the engine of the racing car to the rear axle;
FIG. 6 is an enlarged partial cross-sectional view of the input driveline to depict the swivel coupling recessed into the input cowling of the housing;
FIG. 7 is an enlarged partial cross-sectional view of the input driveline to depict the shift coupler;
FIG. 8 is an enlarged elevational view of the shift coupler apparatus with the shift coupler in the “on” position;
FIG. 9 is an enlarged elevational view of the shift coupler apparatus similar to that of FIG. 9 , but showing the shift coupler in the “off” position;
FIG. 10 is a plan view of the interior side of the cover for the transfer cowling to show the O-ring disposed within the cover; and
FIG. 11 is a cross-sectional view of the cover for the transfer cowling taken along lines 11 - 11 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, a rear end gear box forming part of a racing car and incorporating the principles of the instant invention can best be seen. The rear end gear box 10 is deployed at the rear axle of a racing car, such as a sprint car, in which the engine (not shown) is connected directly to the rear end gear box 10 which is operable to transfer the rotational power from the engine to the rear axle to drive the racing car around the race track. Such racing cars do not utilize a multiple gear transmission between the engine and the rear end gear box 10 , as these racing cars only have two operating conditions, on and off. Accordingly, the rear end gear box 10 includes a shifter 19 that is operable to operatively connect the input from the engine to the rear axle, or to disconnect the input from the engine to the rear axle.
The rear end gear box 10 includes a housing 12 that includes a front input cowling 13 , a rear transfer cowling 14 and a central ring gear cowling 15 . The rear axle 16 of the racing car passes through the center of the ring gear cowling 15 and extends transversely therethrough to drive the rear wheels (not shown) on opposing sides of the rear end gear box 10 . The shifter 19 is mounted on the housing 12 near the transfer cowling 14 . The shifter 19 is operatively connected, such as via a push/pull cable (not shown) to a shift lever (not shown) deployed in the operator's cockpit to control the on/off operative function of the racing car. The rotative movement of the shifter 19 causes a linear movement of the shift mechanism ** within the rear end gear box 10 , as will be described in greater detail below.
The operation of the rear end gear box 10 is best seen in FIG. 5 . The power input shaft 21 is part of the input driveline 20 connected directly to the engine (not shown) and delivers rotational power from the engine into the rear end gear box 10 . Because of the amount of power delivered from the engine and the operational loads associated with the movement of the racing car around a race track, the power input shaft 21 is subject to a substantial amount of vibration and movement. As depicted in FIG. 6 , to minimize the damage caused for an oscillating power input shaft 21 , the power input shaft 21 is connected to a swivel coupler 25 that includes a coupling sleeve 26 mounted on the splines 22 at the end of the power input shaft 21 . The coupling sleeve 26 is formed with rounded crown splines 27 that accommodate slight movements of the input shaft 21 relative to the rear end 10 while engaged with the transfer coupler 28 that is rotatably supported within the front input cowling 13 by bearings 28 a mounting in the housing 12 . A snap ring 29 a retains the transfer coupler 28 against the bearing 29 and retains the swivel coupler 25 within the front input cowling 13 . The coupling sleeve 26 is secured within the transfer coupler 28 by a seal 26 a secured by a snap ring to allow the movement of the coupling sleeve 26 relative to the transfer coupler 28 .
Thus, the power input shaft 21 rotatably drives the coupling sleeve 26 , through interengaged splines, and the coupling sleeve 26 drives the transfer coupler 28 which has an enlarged front end 28 a to accommodate the movement of the rounded crown splines 27 of the coupling sleeve 26 and a smaller rearward end 28 b projecting rearwardly of the bearing 29 . A transfer shaft 31 has a forward portion 32 received within the rearward end 28 b of the transfer coupler 28 so that the rotation of the transfer coupler 28 drives the rotation of the transfer shaft 31 .
As best seen in FIGS. 5 and 7 , the rearward end 33 of the transfer shaft 31 drives a shift coupler 35 which has a forward portion 36 supported by the bearings 36 a and engaged with the rearward end 33 of the transfer shaft 31 . The shift coupler 35 also includes a linearly movable shift collar 37 having splines 37 a engagable with the rearward splines 36 b and being slidable over the stub shaft 39 rotatably supported by bearings 39 a . The shift collar 37 captures the internal shift lever 38 connected to the shifter 19 so that when the shifter 19 is pivoted the internal shift lever 38 slides the shift collar 37 on the stub shaft 39 to move the splines 37 a on the shift collar into or out of engagement with the splines 36 b on the forward portion 36 of the shift coupler 35 .
In operation, which is best seen in FIGS. 5 and 7 - 9 , the transfer shaft 31 rotatably drives the forward portion 35 of the shift coupler 35 . The stub shaft 39 , which carries the shift collar 37 thereon for sliding movement relative to the stub shaft 39 along splines formed on the stub shaft 39 so that the shift collar 37 transfers rotational power from the forward portion 36 of the shift coupler 35 to the stub shaft 39 when the shift collar 37 is slid into engagement with the rearward splines 37 b of the forward portion 37 of the shift coupler 35 . When the shift collar 37 is moved out of engagement with the forward portion 36 of the shift coupler 35 , the driveline 20 is disconnected and rotational power cannot be transferred from the engine to the rear axle 16 .
Referring again to FIG. 5 , the transfer cowling 14 houses the bearing 39 a rotatably supporting the stub shaft 39 and also a second bearing 39 b that also rotatably supports the stub shaft 39 . A drive gear 41 is mounted on the stub shaft 39 between the two stub shaft bearings 39 a , 39 b within the transfer cowling 14 for rotation with the stub shaft 39 . The drive gear is operatively engaged with a driven gear 42 mounted on a second stub shaft 43 , forming the output driveline 40 , which is supported by three bearings 43 a , 43 b and 43 c . The first bearing 43 a is located in the transfer cowling 14 above the bearing 39 b for the first stub shaft 39 . The second bearing 43 b is located at the central portion of the stub shaft 43 , and the third bearing 43 c is located at the inner distal end of the stub shaft 43 .
The second stub shaft 43 has the driven gear 42 supported within the transfer cowling 14 along with the drive gear 41 so that both the drive gear 41 and the driven gear 42 can be accessed quickly and easily by removing the cover 45 that is bolted to and sealed against the transfer cowling 14 . Preferably, as depicted in FIGS. 10 and 11 , the cover 45 carries an O-ring 46 that seals the cover 45 when compressed against the peripheral ring of the transfer cowling 14 . The O-ring 46 provides an effective seal to prevent leakage of lubricating oil from the housing 12 , but is carried by the cover 45 so that the replacement of the cover 45 on the transfer cowling 14 does not require the manipulation of a conventional gasket that is placed between the cover 45 and the transfer cowling 14 .
Referring again to FIG. 5 , the second stub shaft 43 also carries at the inner distal end a pinion 48 that is engagable with a ring gear 49 mounted within the ring rear cowling 15 . The ring gear 49 is affixed to the rear axle 16 to transfer rotational power thereto and affect a driving of the rear axle 16 . Accordingly, the driveline 20 transfers rotational power from the engine through the swivel coupling 25 , the shift coupler 35 , the interengaged transfer gears 41 , 42 and the pinion 48 to drive the ring gear 49 and the rear axle 49 .
Placement of the swivel coupling 25 internally of the housing 12 would normally interfere with the rotation of the ring gear 49 . To allow the recessing of the swivel coupling 25 into the housing 12 to allow the housing 12 to provide a stable and rigid support of the swivel coupling 25 , the power input shaft 21 is offset to the right of the line of the second stub shaft 43 carrying the pinion 48 . Specifically, the center of the power input shaft 21 , as well as the transfer shaft 31 and the first stub shaft 39 , were rotated approximately 16 degrees about the centerline of the second stub shaft 43 , as is represented in FIG. 4 . Accordingly, a vertical plane passing through the center of the first stub shaft 39 is offset to the right of a vertical plane passing through the center of the second stub shaft 43 .
Since the power input shaft 21 is properly mounted in direct longitudinal alignment with the engine, particularly due to the amount of power being transferred through the power input shaft 21 , the entire remaining mass of the rear end gear box 10 has the center of gravity shifted to the left, as compared to a conventional rear end gear box structure with the first and second stub shafts 39 , 43 being vertically aligned. The shift in the center of gravity of the rear end gear box 10 has a resulting shift in the center of gravity of the entire racing car to the left of the longitudinal centerline of the racing car. As a consequence, the racing car has more stability in turns around the race track.
Recessing the swivel coupling 25 and the bearing 29 associated with the swivel coupling 25 into the housing 12 allows both the swivel coupling 25 and the bearing 29 to be lubricated by the oil within the housing 12 . This direct lubrication of the swivel coupling 25 and the bearing 29 , along with the more rigid support of the swivel coupling 25 , results in a longer operating life of the swivel coupling 25 and the bearing 29 compared to the conventional mounting of the swivel coupling externally of the housing 12 .
It will be understood that changes in the details, materials, steps and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention. | A rear end gear box for a racing car has the swivel coupler and the bearing rotatably supporting the swivel coupler mounted within the rear end housing so that oil within the rear end housing will lubricate the swivel coupler and its bearing. The input shaft delivering rotational power from the engine is offset to the right of the driven shaft mounted within the rear end housing so that the center of gravity of the rear end is shifted to the left of the car centerline to increase stability of the car in turns. The recessed swivel coupler has an extended operating life due to increase stability and rigidity provided by the support from the housing structure. The cover for the back end of the rear end structure where the transfer gears are located is provided with an O-ring to facilitate a quick change of the transfer gears. | 8 |
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application No. 60/558,078, entitled, “Subsea Test Tree,” filed Mar. 30, 2004, and to U.S. Provisional Application No. 60/580,474, entitled, “Tools for Completing Subsea Wells,” filed Jun. 17, 2004, each of which is herein incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates to subsea well technology, and specifically to an improved tubing hanger running tool and subsea test tree control system and method of controlling hydraulic/electric tools or equipment used during drilling, testing or completion of a subsea well.
BACKGROUND OF THE INVENTION
[0003] A subsea well constructed for producing hydrocarbons consists of a series of concentric drilled and cased bores. The casings typically include sections of threaded and coupled pipes screwed together. The casings are run into the well bore, suspended (landed) in a wellhead attached to the first casing string (referred to as conductor pipe), and cemented in place by circulating cement down the casing and up into the annular area between the casing and well bore.
[0004] In the process of drilling and equipping (completing) a subsea well, it is often necessary to suspend production tubing in the subsea wellhead or christmas tree with a device known as a tubing hanger. The tubing typically consists of sections of threaded and coupled steel pipes similar to casing, but smaller in diameter and usually higher in pressure rating. Unlike casing, the tubing is not cemented in place and therefore can be replaced. In addition to suspending the tubing in the wellhead or in a Christmas tree, the tubing hanger also seals off the annular space between the tubing and the production casing and provides access to down-hole devices such as safety valves, chemical injection ports, down-hole pressure gauges, as well as other devices.
[0005] In some drilling and completion procedures, a subsea well is connected to a floating platform on the surface of the sea through a Blowout Preventer Stack (BOP) and a marine drilling riser. For example, this is often done in performing a Drill Stem Test or a flow test and cleanup for a completed subsea well. During such procedures, a subsea test tree (SSTT) is landed in the wellhead, or subsea tree, for safety purposes. The SSTT is the primary safety device in containing well pressure in the event that the floating drilling vessel is required to disconnect from the well in an emergency.
[0006] The process of running the SSTT is cumbersome and time consuming to the well operator and requires the rental of expensive equipment (i.e. control panel, hydraulic power supply, control umbilical, hose reel, etc.). Along with the drilling rig time associated with rigging up and running the umbilical and strapping it to the work string, this procedure can add five hundred thousand dollars or more to the well cost, depending on the water depth. The cost can include the rental cost of the SSTT itself, the umbilical, and the control panel and hydraulic power system, as well as the rig time to run the SSTT with the umbilical, strapping the umbilical to the tie back string and rigging up the hydraulic control system.
SUMMARY OF THE INVENTION
[0007] In general, in an aspect, the invention provides a system for providing power to elements down-hole in a subsea well. The system includes a control pod having at least one shuttle valve, a down-hole hydraulically-actuated device having at least one internal porting mechanism in fluid communication with the at least one shuttle valve, a blowout preventer stack connected to the down-hole device, the blowout preventer stack including a first ram and a second ram, and a choke line in fluid communication with an area between the first ram and the second ram. The at least one shuttle valve controls distribution of hydraulic pressure applied through the choke line to the internal porting mechanism for selective distribution of power to the hydraulically-actuated device.
[0008] Embodiments of the invention may include one or more of the following features. The shuttle valves may be battery activated shuttle valves. The system may include an acoustic signal generator. The shuttle valves may be controlled by an acoustic signal generated by the acoustic signal generator. The shuttle valves can be controlled with electronic signals received by the control pod. The shuttle valves can be electrically controlled. The control pod may include a receiver to decode pressure pulses generated to control the shuttle valves. The down-hole hydraulically actuated device may include a component in at least one of a tubing hanger running tool, a subsea test tree, and a tubing hanger. The blowout preventer stack may include a port positioned between the first ram and the second ram. The choke line can be in fluid communication with the port. The system can include an electronic control panel and a slip ring to provide control commands to the shuttle valves in the control pod.
[0009] Additional aspects of the invention are directed to a method of providing hydraulic and electric power to tools in a subsea test tree system, the system comprising a blowout preventer stack having a first ram and a second ram and a choke line through which hydraulic pressure is provided to a port in the blowout preventer stack. The method includes isolating an area between the first ram and the second ram of the blowout preventer, distributing hydraulic pressure through the choke line to the area between the first ram and the second ram of the blowout preventer, and controlling the distribution of hydraulic pressure through the choke line to a hydraulically-actuated device by actuating shuttle valves.
[0010] Embodiments of the invention may include one or more of the following features. The method may further comprise generating an acoustic signal and controlling the shuttle valves with the acoustic signal. The method may also comprise generating pressure pulses, receiving the pressure pulses in a control pod housing the shuttle valves, and decoding the pressure pulses to control the shuttle valves. The method may include closing the area between the first ram and the second ram above and below an inlet from the choke line and providing a seal for hydraulic fluid in the blowout preventer.
[0011] Various features of the invention may provide one or more of the following capabilities. Using the sealing capabilities of the BOP and the existing hydraulic power and control functions allows the user to avoid having to obtain the umbilical, the control unit and a hydraulic power supply. Also, rig time is lessened due to the elimination of the necessity of hooking up the aforementioned components, as well as the time required to run the umbilical. Savings can be as much as one-half of the standard cost of renting and running a known subsea test tree. Safety is enhanced by the elimination of the control umbilical required in the current SSTT designs.
[0012] Various features of the invention may provide one or more of the following capabilities. In embodiments of the invention, the need for a hose reel, a control umbilical, a hydraulic control panel, a hydraulic power supply and down-hole accumulator are substantially eliminated. The rig time associated with running the control umbilical is also substantially eliminated. The efficiency of the drilling of a subsea well can be more cost effective and safer for the user.
[0013] These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings briefly described below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings briefly described below.
[0015] FIG. 1 is a schematic diagram of a floating drilling rig.
[0016] FIG. 2 is a schematic diagram of a Subsea Test Tree/Tubing Hanger Running Tool.
[0017] FIG. 3 is a schematic diagram of an alternative Subsea Test Tree/Tubing Hanger Running Tool.
[0018] FIG. 4 is a schematic diagram of a Subsea Test Tree/Tubing Hanger Running Tool having an electric power ram.
[0019] FIG. 4A is a magnified schematic diagram of the electric power ram of FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
[0020] The features and other details of the invention will now be more particularly described with reference to the accompanying drawings. It will be understood that particular embodiments described herein are shown by way of illustration and not as limitations of the invention. The principal features of this invention can be employed in various embodiments without departing from the scope of the invention.
[0021] Embodiments of the invention are related to subsea well technology, and specifically to an improved tubing hanger running tool (THRT) and subsea test tree (SSTT). Embodiments of the invention eliminate a control umbilical and associated hydraulic power pack, as well as associated reel and control panel. Embodiments of the invention use a choke and/or kill line of the blowout preventer system (BOP) to supply hydraulic power. Further, embodiments of the invention use battery powered shuttle valves to direct hydraulic fluid through internal piping and ports to perform many functions in a subsea system. Embodiments of the invention supply hydraulic power to the THRT and to the tubing hanger and SSTT through a blowout preventer that is generally employed in the drilling and completion (equipping for production) of a subsea well. Embodiments and portions of the invention can be used for completing a subsea well, flow testing a subsea well, or for purposes other than completing or testing. Other applications of the embodiments will be apparent to those skilled in the art.
[0022] In embodiments of the invention, hydraulic power is provided through a port in the side of the THRT, rather than through a control umbilical. The port is isolated between two pipe rams in the blowout preventer (BOP). Embodiments of the invention further provide closing the pipe rams such that hydraulic power can be supplied to the port through the choke or kill line that is available on standard subsea blowout preventer stacks. Further, battery-powered shuttle valves are used to direct hydraulic fluid through internal piping to functions that require the hydraulic fluid. Shuttle valves are controlled in at least one of a number of ways, including, but not limited to, by acoustic signals, electronic signals, pressure pulse telemetry, and electrically.
[0023] Referring to FIG. 1 , a schematic of the general arrangement of a floating drilling operation and selected systems therein is shown. A subsea well system 10 includes a floating drilling rig 12 positioned above sea level, and a marine riser 14 , a lower marine riser package 16 and a BOP stack 18 , all positioned below sea level. Subsea wells are built by establishing a wellhead housing on a conductor casing pipe, and with a blowout preventer stack 18 installed, drilling a well bore down to the producing formation and installing concentric casing strings, which are cemented at the lower ends and sealed with mechanical seal assemblies at each string's upper end. The lower marine riser 16 is a sub-system of the blowout preventer stack 18 , and allows the rig and riser system to be disconnected from the BOP stack in the event an emergency disconnect is required. The system depicted is a guide-lineless system. Other systems, including systems that utilize guide lines, are known in the art.
[0024] In order to equip the cased well for production, a tubing string is run in through the BOP 18 and a tubing hanger is landed in the wellhead. Thereafter, the BOP stack 18 is removed and replaced by a tree having one or more production bores extending vertically to respective lateral production fluid outlet ports in the wall of the tree. In an alternate embodiment, the tubing hanger may be landed in a subsea christmas tree mounted on the wellhead. The tubing hanger is generally installed by using a hydraulically activated tubing hanger running tool.
[0025] To equip the well for production, a tubing hanger running tool (THRT) 26 and a subsea test tree (SSTT) 28 may be employed. Referring to FIG. 2 , components that may be used with the THRT 26 and SSTT 28 include a hose reel 30 , a hydraulic power pack 32 , an electro-hydraulic control panel 34 , an electro-hydraulic control umbilical 36 , a flow control head 38 , a BOP control panel 40 , a choke line 42 , a BOP control umbilical 44 , a marine riser 14 , an accumulator 46 for the THRT and the SSTT, a control pod 48 for the THRT and the SSTT, a retainer valve 50 , a hydraulic disconnect 52 , a ball joint 54 , an annular BOP 56 , BOP pipe rams 58 and a tubing hanger 60 . The tubing hanger 60 is connected to the THRT 26 , the umbilical 36 is connected to the control pod 48 , and the assembly is run into the well through the drilling riser 16 and blowout preventer stack 18 , which are attached to the wellhead. Alternatively, the BOP 56 may be landed on the subsea christmas tree, and the tubing hanger may be run and landed in the subsea christmas tree. The THRT 26 and the SSTT 28 can be run together or separately.
[0026] The THRT 26 provides several functions, including but not limited to: facilitating “soft landing” features of the tubing hanger; testing of the various tubing hanger seals; and actuating locking rings to lock the tubing hanger in place. These functions may be actuated by hydraulic pressure delivered to the THRT 26 from the surface vessel (e.g., the floating production platform or drilling rig 12 ) through the control umbilical 36 connected to the dedicated hydraulic power unit 32 on the surface vessel 12 , and operated with the hydraulic control panel 34 . Generally, the control umbilical 36 system transfers high and low pressure fluid supply, annulus fluids and electrical power/signals to the BOP, subsea tree and other equipment down-hole.
[0027] The SSTT 28 has hydraulically actuated valves that are powered and controlled through the electro-hydraulic control line 36 running from the surface platform 12 to the SSTT 28 . The system is run on a high pressure riser, or tie back string 63 , run inside the marine riser 14 and landed and sealed inside the wellhead or subsea tree. The control umbilical 36 is strapped to the tieback string 63 . A surface tree is hooked up to the tie back string to control the flow of the well and allow wireline lubricator access to the well for wireline work. The SSTT 28 cuts the wireline, seals the well, and releases the tie back string in the event that the platform is required to disconnect from the well, for example, in an emergency.
[0028] Referring to FIG. 3 , the electro-hydraulic control panel 34 , power pack 32 , hose reel 30 and electro-hydraulic umbilical 36 of the system of FIG. 2 can be replaced by an electronic control panel 61 and a slip ring 62 around the running string 64 . The system of FIG. 3 operates without a down-hole accumulator. The system includes the retainer valve 50 , the hydraulic disconnect 52 , the control pod 48 , the pipe rams 58 , the SSTT 28 and the THRT 26 . The electronic control panel 61 and the slip ring 62 provide the control commands (e.g., electronically, electrically, acoustically, etc.) to the battery operated shuttle valves in the control pod 48 . The shuttle valves direct/control hydraulic power fluid to the various functions of the THRT 26 , the tubing hanger 60 and the SSTT 28 .
[0029] The hydraulic power in the system of FIG. 3 is provided via a choke/kill line 42 . The control pod 48 includes a series of shuttle valves 68 . The series of shuttle valves 68 in the control pod 48 for the THRT/SSTT are manifolded to hydraulic power supplied through internal porting in the THRT 26 and the SSTT 28 . The hydraulic power is supplied through the choke or kill line 42 via a port in the THRT 26 . The port is spaced between the lower two pipe rams 58 in the BOP stack 18 . For example, the rams 58 are closed, which isolates the port so the port can receive hydraulic power from the choke/kill line 42 . The choke or kill line 42 is generally approximately 3 inches in diameter; however, other dimensions are possible and envisioned. The hydraulic power can have sufficient capacity/volume so as to substantially eliminate the need for a down-hole accumulator.
[0030] Control of the hydraulic power fluid to the various functions to be operated is through the internal manifold and shuttle valves 68 in the control pod 48 . The lower pipe rams 58 are closed above and below the inlet from the kill line to provide a seal for the hydraulic power fluid to enter a port in the THRT 26 . The port is connected to the internal manifold and shuttle valves.
[0031] When actuated, the shuttle valves 68 direct hydraulic power to the various functions in the tubing hanger/THRT/SSTT. These functions include, but are not limited to, soft landing, seal testing, and a tubing hanger lockdown function.
[0032] A hydraulic passage can be made from the THRT 26 , through the tubing hanger and, by using galley seals, is connected with a passageway through the subsea christmas tree. On the outside of the tree an additional manifold of shuttle valves 68 distributes the hydraulic power to the various hydraulically activated tree functions (valves, connectors, test ports, etc.) The shuttle valves 68 may be battery activated and controlled, as described below. In this way, the tree can be functioned/operated without the need for a separate electrical umbilical.
[0033] The shuttle valves 68 in the control pod 48 are battery operated, for example. Battery power to the shuttle valves 68 can be controlled in a number of ways, now discussed for simplicity in terms of shuttle valve controls. The battery pack for the shuttle valves 68 may be controlled by acoustic signal through the water (or work string). The signal is picked up and decoded by a receiver in the control pod 48 and the shuttle valves are then actuated by electric impulse from the decoder. Electric power is provided by a battery pack in the control pod for the SSTT 28 and the THRT 26 .
[0034] Referring to FIGS. 4 and 4 A, a separate set of rams 58 in the BOP stack 18 can be used to provide electric power to the control pod 48 . The BOP includes the rams 58 , 59 , a power sub 72 having insulation 74 and split lines 76 that provide electrical power from the BOP control umbilical 44 . The opposing rams 58 , 59 include electrodes 70 horizontally opposed but offset in the vertical plane. Electric power is supplied from the control umbilical 44 for the BOP stack 18 . The configuration shown in FIG. 4A is non-orienting and transmits electric power through anodes in the ram body to the power sub in the running string. The annulus in the BOP stack 18 is filled with a non-conductive fluid circulated into place through the choke or kill line. Pressure on the rams 58 , 59 as they close around the power sub squeezes out the non-conductive fluid and makes the electrical connection. An orienting device can be used in the wellhead and BOP stack 18 . Wet mate-able electrical connectors can be used in the rams 58 and the power sub.
[0035] In alternatives of the embodiments described herein, the principle applied to the control pod, THRT and SSTT can also be applied to a christmas tree running tool. In the case of a christmas tree running tool, the hydraulic power may be supplied through the tree running/landing string. The tree running tool (CTRT) is hydraulically locked to the tree, and hydraulic passages connect from a manifold in the CTRT, through the tree to another manifold external to the tree, thence to the various tree functions. Hydraulic power through both hydraulic manifolds may be controlled by battery operated shuttle valves. The shuttle valves are controlled according to at least one of the various methods discussed above.
[0036] In embodiments of the invention, the battery operated shuttle valves are controlled by acoustic signals and acoustic decoder. Alternatively, the shuttle valves 68 are controlled by pressure pulse telemetry as is used in “logging while drilling” (LWD) tools. The coded series of pressure pulses is generated on the surface and decoded by a receiver in the control pod 48 . The receiver directs electric power, from a battery pack in the control pod 48 , to the shuttle valves 68 . A further alternative method by which to control the shuttle valves 68 is by a special landing string containing an electric conductor embedded in or attached to the wall of the pipe. In this method the electric power is supplied directly to the shuttle valves 68 through a multiplexing system similar to a multiplex system for controlling production from subsea wells. A still further alternative includes controlling the shuttle valves by use of a landing string employing an electronic signal transmission wire attached to or embedded in the pipe to control battery powered shuttle valves 68 in the control pod 48 . For example, Grant Prideco's product Intellipipe™ can be used to provide an electronic signal transmission. Any other method of delivering a signal to a battery pack power supply in order to activate the shuttle valves 68 without the use of an umbilical connection to the down-hole tools is possible and envisioned.
[0037] From the foregoing detailed description it has been shown how the objects of the invention have been obtained in a preferred manner. However, modifications and equivalence of the disclosed concepts such as those which would occur to one of ordinary skill in the art are intended to be included within the scope of the present invention. Such equivalents are considered to be within the scope of the present invention.
[0038] Various substitutions, alterations, and modifications may be made to the invention without departing from the spirit and scope of the invention as defined by the claims. Other aspects, advantages, and modifications are within the scope of the invention. The contents of all references, issued patents, and published patent applications cited throughout this application are hereby incorporated by reference. The appropriate components, processes, and methods of those patents, applications and other documents may be selected for the present invention and embodiments thereof. | A system for providing power to elements down-hole in a subsea well includes a control pod having at least one shuttle valve, a down-hole hydraulically-actuated device having at least one internal porting mechanism in fluid communication with the at least one shuttle valve, a blowout preventer stack connected to the down-hole device, the blowout preventer stack including a first ram and a second ram, and a choke line in fluid communication with an area between the first ram and the second ram. The at least one shuttle valve controls distribution of hydraulic pressure applied through the choke line to the internal porting mechanism for selective distribution of power to the hydraulically-actuated device. | 4 |
This is a continuation of application Ser. No. 601,943, filed Oct. 22, 1990, which is a division of application Ser. No. 307,326, filed Feb. 6, 1989, now U.S. Pat. No. 4,990,163, issued Feb. 5, 1991.
FIELD OF THE INVENTION
The present invention relates to materials and processes which enhance bone ingrowth in porous surfaces, such as titanium implants. Specifically, materials and processes are presented which permit calcium phosphate ceramic materials to be uniformly deposited by electrophoresis.
BACKGROUND OF THE INVENTION
Bone tissue consists of approximately 60-67% by weight of calcium phosphate crystals finely dispersed in a collagenous matrix, and also contains about 10% water. Some bone-forming reactions have been described. However, neither the actual sequence nor the specific mechanisms leading to bone formation are fully understood. It is logical, however, to consider bone formation as the result of two major trains of events, i.e., a first one that produces the collagen precursor matrix; the next a sequence of steps that leads to calcification, i.e., the mineralization of the organic matrix. These two phases are distinct, since it is possible to microscopically distinguish the calcified tissue from the non-calcified (osteoid) tissue in bone tissue that is being laid down.
Cementless fixation of permanent implants has become a widespread surgical procedure which aids in avoiding some of the late complications of cemented prosthesis. See, "Total joint replacement arthroplasty without cement", Galante, J. O., guest editor Clin. Orthop. 176, section I, symposium, pages 2-114 (1983); Morscher, E., "Cementless total hip arthroplasty", Clin. Orthop. 181, 76-91 (1983); Eftekhar, N. S., "Long term results of total hip arthroplasty", Clin. Orthop. 225, 207-217 (1987). In principle, cementless fixation can be achieved by using any of three methods: bone tissue ingrowth in porous coatings, bone tissue apposition on undulated, grooved, or surface structured prostheses, and fixation through chemical reaction with a bioactive implant surfaces. See, Hulbert, S. F., Young, F. A., Mathews, R. S., Klawitter, J. J., Talbert, C. D., Stelling, F. H., "Potential of ceramic materials as permanently implantable skeletal prostheses", J. Biomed. Mater. Res. 4, 433-456 (1970); Griss, P., Silber, R., Merkle, B., Haehner, K., Heimke, G., Krempien, B., "Biomechanically induced tissue reactions after Al 2 O 3 -ceramic hip joint replacement. Experimental study and early clinical results", J. Biomed. Mater. Res. Symp. No. 7, 519-528 (1976); Hench, L. L., Splinter, R. J., Allen, W. C., Greenlee, T. K., Jr., "Bonding mechanisms at the interface of ceramic prosthetic materials", J. Biomed. Mater. Res. Symp. 2, 117-141 (1973). Common to these three principles of fixation is the necessity that the surrounding tissues establish and maintain a bond with the device. This can be contrasted with the cemented reconstructions of which failure is invariably associated with destruction or resorption of surrounding bone tissue. See, Charnley, J., "Low-friction arthroplasty of the hip", Springer-Verlag, Berlin, Heidelberg, New York (1979); Ducheyne, P., "The fixation of permanent implants: a functional assessment", Function Behavior of Orthopaedic Biomaterials, Vol. II, CRC Press, Boca Raton, Fla. (1984).
Cementless fixation methods are not free from limitations. When porous coated devices are used the device is not permanently fixed at the time of surgery. A finite time is needed for bone tissue to develop in the porous coating interstices and eventually create sufficient fixation for patients to use their reconstructed joints fully.
It is known that bioactive materials such as calcium phosphate ceramics (CPC) provide direct bone contact at the implant-bone interface and guide bone formation along their surface. These effects are termed collectively osteoconduction. See, Gross, V., Schmitz, H. J., Strunz, V., "Surface Activities of bioactive glass, aluminum oxide, and titanium in a living environment. In: "Bioceramics: material characteristics versus in vivo behavior", Ed P. Ducheyne, J. Lemons, Ann. N.Y. Acad. Sci., 523 (1988); R. LeGeros et al., "Significance of the porosity and physical chemistry of calcium phosphate ceramics: biodegradation-bioresorption", In: "Bioceramics: material characteristics versus in vivo behavior", Ed P. Ducheyne, J. Lemons, Ann. N.Y. Acad. Sci., 523 (1988). This property of bioactive ceramics is attractive, not only because it may help in averting long term bone tissue resorption, but also because it enhances early bone tissue formation in porous metal coatings such that full weight bearing can be allowed much sooner after surgery. Calcium phosphate ceramics, although widely known to be bone conductive materials, do not, however, have the property of osteo-induction, since they do not promote bone tissue formation in non-osseous implantation sites.
The enhancement of bony ingrowth was first documented with slip cast coatings. Ducheyne, P., Hench, L. L., "Comparison of the skeletal fixation of porous and bioreactive materials", Trans. 1st Mtg. Europ. Soc. Biomater, p. 2PS, September, 1977, Strasbourg; Ducheyne, P., Hench, L. L., Kagan, A., Martens, M., Mulier, J. C., "The effect of hydroxyapatite impregnation on bonding of porous coated implants", Trans. 5th annual mtg., Soc. Biomat. p. 30 (1979); Ducheyne, P., Hench, L. L., Kagan, A., Martens, M., Burssens, A., Mulier, J. C., "The effect of hydroxyapatite impregnation on skeletal bonding of porous coated implants", J. Biomed. Mater. Res. 14, 225-237 (1980). A porous stainless steel fiber network was coated with a slip cast CPC lining, and a marked increase of bone ingrowth was observed in comparison to the same porous metal without the CPC lining. This effect was pronounced at 2 and 4 weeks, but had disappeared at 12 weeks, because the slower full ingrowth without CPC lining had achieved the same level of ingrowth as that of the earlier extensive ingrowth caused by the osteoconductive lining.
Subsequently, the effect was studied mostly with plasma sprayed coatings, by numerous researchers. The studies to date, with the exception of one, have confirmed the beneficial effect of calcium phosphate based ceramic linings. See, J. L. Berry, J. M. Geiger, J. M. Moran, J. S. Skraba, A. S. Greenwald, "Use of tricalcium phosphate or electrical stimulation to enhance the bone-porous implant interface", J. Biomed. Mater.Res. 20, 65-77 (1986); H. C. Eschenroeder, R. E. McLaughlin, S. I. Reger, "Enhanced stabilization of porous coated metal implants with tricalcium phosphate granules", Clin. Orthop. 216, 234-246 (1987); D. P. Rivero, J. Fox, A. K. Skipor, R. M. Urban, J. O. Galante, "Calcium phosphate-coated porous titanium implants for enhanced skeletal fixation", J. Biomed. Mater. Res. 22, 191-202 (1988); M. D. Mayor, J. B. Collier, C. K. Hanes, "Enhanced early fixation of porous coated implants using tricalcium phosphate", Trans. 32nd ORS, 348 (1986); Cook, S. D., Thomas, K. A., Kay, J. F., Jarcho, M., "Hydroxyapatite-Coated porous titanium for use as an orthopaedic biologic attachment system" , Clin. Orthop. 230, 303-312 (1988); H. Oonishi, T. Sugimoto, H. Ishimaru, E. Tsuji, S. Kushitani, T., Nasbashima, M. Aona, K. Maeda, N. Murata, "Comparison of bone ingrowth into Ti-6A1-4V beads coated and uncoated with hydroxyapatite", Trans. 3rd World Biomat. Conf., Kyoto, p. 584 (1988). Yet, the magnitude of the effect has varied from study to study, and was not as pronounced as in an experiment performed by the present inventor. See, Ducheyne, et al., "The effect of hydroxyapatite impregnation . . . ", supra. More recently, it has been found that porous titanium, spherical bead coatings, plasma sprayed with two calcium phosphate powders (either hydroxyapatite or beta-tricalcium phosphate before spraying) also did not yield a clinically meaningful effect. See, Ducheyne, P., Radin, S., Cuckler, J. M., "Bioactive ceramic coatings on metal: structure property relationships of surfaces and interfaces", "Bioceramics 1988" Ed. H. Oonishi, Ishiyaku Euroamerica, Tokyo (1988 in press).
The variability of the effect among the studies noted suggests materials and processing induced parametric influences. The extensive characterization of some plasma sprayed coatings has unveiled that considerable changes of the physical and chemical characteristics of the ceramic subsequent to the deposition are possible. Specifically, differences in chemical composition, the trace ions present, the phases and their crystal structure, macro- and micro-porosity in the ceramic film, specific surface area, thickness, size and morphology of the pores and of the porous coating itself, and the chemical characteristics of the underlying metal may have occurred among the various studies.
Much of the prior art teaches the use of plasma spray techniques to form ceramic coating. Limitations of plasma spray coatings include: possible clogging of the surface porosity, thereby obstructing bone tissue ingrowth; difficulty in producing a uniform coating--although the HA can flow at the time of impact, plasma spraying is still very much a line of sight process, thus, it is not possible to coat all surfaces evenly, and certainly not the deeper layers of the coating, or the substrate; and finally if viscous flow is wanted, high temperatures are reached by the powders and uncontrolled, and thus unwanted transformation reactions can occur. Efforts to avoid these transformation reactions can be successful by minimizing the time of flight. However, a low intensity of viscous flow will result from this and thus, incomplete coverage of the metal can be the result. Thus, at present, it is difficult to obtain an optimal end-product, however, improved ceramic powders may overcome these limitations and provide useful coatings using plasma spraying techniques.
The search thus continues for the optimal characteristics of the ceramic and for a process by which calcium phosphate ceramics may be deposited upon porous metal surfaces in a uniform manner and with predictable results. Although it is possible to coat flat plates of metals such as titanium by electrophoretic deposition, actual experiments by the applicants to deposit a uniform ceramic film on porous titanium using the information available prior to the current invention were unsuccessful. Referring to FIG. 1 and FIG. 2, there is illustrated a portion of a porous metallic device which is comprised of a woven mesh. Analysis of porous metallic devices with failed ceramic coatings showed that the ceramic particles were deposited primarily in the few areas indicated in FIG. 1 and FIG. 2. It is apparent that only those areas that were well exposed to the flow of particles were covered. During electrophoresis, the particles are electrically attracted to the metal; with a finite amount of particles in the solution, the particles will migrate first to the most accessible areas 20 of the metallic device 10, such as the tops of the wires. Further, some particles will be able to cross the potential field created by the wires if the particles are sufficiently far from each of the wires and be deposited on the substrate 30 to which the woven mesh is affixed. However, very few particles actually overcome this combination of attractive forces and adhere to the interstitial areas 15. Thus, the known electrophoretic process to coat flat titanium plates does not provide an adequately coated device.
Therefore, it can be seen that there remains a long felt, yet unfulfilled need for both a material with optimum characteristics and a deposition process which will allow uniform deposition of ceramic materials in a repeatable and commercially viable manner.
SUMMARY OF THE INVENTION
The present invention provides products and methods for enhancing the calcification phase of bone tissue growth. Since the calcification phase is a rate-limiting step of the reactions leading to bone tissue formation, the enhancement of calcification also enhances overall bone growth rates. Thus, the present invention provides materials and processes whereby calcification in porous coated bone implants is enhanced.
It has now been found that by using powdered calcium phosphate of sufficiently small particle size and of selected compositions, substantially improved coating materials result. Moreover, by using a lower voltage potential, and commensurately, a longer deposition time cycle, uniform calcium phosphate films of acceptable thickness and quality may be electrophoretically deposited. In order to prevent agglomeration of the small particles while in solution, the process of the present invention utilizes ultrasonic agitation during the deposition process.
The size of the particles used to practice the present invention is critical. As particle size is decreased, its ability to travel and adhere to the interstices improves. Also, if the weight concentration of the particles in solution is kept constant, then a larger quantity of particles is available and proportionately, more will remain in suspension and migrate into the interstices. The calcium phosphate powder of the present invention uses particles with a mean diameter of about 1×10 -6 to 5×10 -6 meters. The small particle size leads to the problem of agglomeration, both in the powdered form prior to mixing in solution and by the formation of clusters in solution. It is necessary therefore, to subject the solution to ultrasonic agitation immediately upon mixing, and to maintain this agitation during the electrophoretic deposition.
The deposition process of the present invention discloses optimal ranges for several parameters which must be controlled. Specifically, electric potential gradients between 45-90 V/cm, and most preferably of 90 V/cm are disclosed. Previously, preferably much higher gradients between 105-150 V/cm had been used for flat plate deposition. When the electric potential gradient is reduced, the time of deposition must be increased to achieve a sufficient thickness in the deposited film. However, the time for depositing layers between 20-80×10 -6 meters by the process disclosed is less than 60 seconds at the highest potential gradient of the range disclosed, i.e., 90 V/cm and using the porous mesh coatings of FIG. 1. Such conditions are considered acceptable for most commercial applications.
The preferred coating created in accordance with the present invention may also be subsequently sintered. The small particle size used results in shrinkage occurring during sintering, thereby leading to exposure of the underlying metal if the coating is too thin. For this reason, a minimum thickness for uniform ceramic coatings subsequent to sintering of 5×10 -6 meters and preferably of 20×10 -6 meters is disclosed.
The coatings achieved by the present invention, using ultrasonic agitation during the deposition process, provide a consistent electrophoretic yield from deposit to deposit, and also provide a great number of coatings for a given suspension bath. This advantage provided by the present invention results in a considerable increase in production efficiency and economic viability. The solution of the present invention lacks the agglomerations typically present; these large clusters do not remain in suspension and thereby substantially limit the number of films which may be deposited from one suspension. Previously, no more than 3 uniform depositions on flat titanium could be made. The presence of agglomerations in the prior art process reduces the amount of smaller particles available for deposition in a given solution concentration by weight, these few small particles are then used rapidly, and the solution must be replaced frequently in order to continue further deposition.
The present invention also provides novel electrophoretic coatings, which consist essentially of oxyhydroxyapatite and alpha- and beta-tricalcium phosphate, and which are essentially free of tetracalcium phosphate. By not heat treating in air (calcination) the calcium phosphate powder used and also by using a calcium-deficient hydroxyapatite with a limited amount of adsorbed water, substantially improved coatings are achieved. Normally, if calcium deficient hydroxyapatite is calcined prior to electrophoresis and subsequently sintered, tetracalcium phosphate is formed. This compound is unwanted since it is much too stable and will therefore not enhance bone ingrowth significantly. The present invention avoids the formation of tetracalcium phosphate and obtains oxy-hydroxyapatite, and alpha- and beta-tricalcium phosphate, which is highly desirable. It has also been found that it is preferable that the calcium deficient powder contain less than about 5% by weight of adsorbed water; if the water content is higher, electrophoretic deposition is highly ineffective in the non-aquepous suspension used in the present invention.
It is therefore an object of the present invention to create CPC materials which are useful in hard tissue reconstruction as materials which enhance bone tissue calcification.
It is a specific object of the present invention to provide easily reproducible, porous coated metal devices and which have uniform CPC coatings.
It is another object of the present invention to provide ceramic materials which will enhance bone formation in joint replacement devices.
Other objects will become apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a portion of porous metal mesh which has an insufficient coating of calcium phosphate ceramic deposited by electrophoresis using materials and processes other than those disclosed;
FIG. 2 is a cross sectional view of the porous metal mesh of FIG. 1.
FIG. 3 is a view of a mesh similar to FIG. 1, but coated in accordance with present invention;
FIG. 4 is a cross sectional view of the coated mesh of FIG. 3.
DETAILED DESCRIPTION
The present invention provides ceramic materials and the process for making them which enhance calcification to a greater degree than any other previously known ceramic coatings.
The approach taken contradicts the logic and thinking in the field of bioactive ceramics. The state-of-the-art of calcium phosphate ceramic coatings for enhancement of bone tissue ingrowth teaches the use of either hydroxyapatite (HA) coatings or beta-tricalcium phosphate coatings or a combination of both. It does so in view of the relatively high stability of the HA or the perceived slow degradability of beta-TCP. HA is considered stable and it is desired to be stable since it is used as a coating on dense, non-porous coated prostheses in which the HA coating serves as a permanent attachment vehicle. The state-of-the-art also teaches plasma spray deposition. It has now been found, however, that the choice of these materials, by themselves or in combination with plasma spraying is a poor choice. Stable or slowly degrading materials or coatings have been found to be suboptimal. Instead, the present invention teaches the use of materials and coating with the highest dissolution rate as measured by the release of calcium.
The materials of the present invention are unstable Ca-(PO 4 ) compounds that are a microscopic mixture of electrophoretically formed Cy-P type materials and not a physical mixture of powders of different Ca-P type materials; in addition, they have a specific surface area which, in the case of coatings, exceeds 1 m 2 /g. Separately, hydroxyapatite, oxy-hydroxyapatite, alpha- and beta-tricalcium phosphate do not have a high dissolution rate; however, when formed by electrophoresis and subsequently sintered in a microscopic mixture, the resulting dissolution rate increases by ten fold. This result is particularly surprising since the HA, oxy-HA, alpha- and beta-TCP are powders, and it would be expected by those of ordinary skill to have a higher dissolution rate since powders have a much greater exposed surface area than coatings.
The present invention provides a novel prosthetic surface for implantation in bony tissue comprising a porous titanium substrate uniformly coated with a coating consisting essentially of oxyhydroxyapatite, alpha-tricalcium phosphate (hereinafter alpha TCP) and beta-tricalcium phosphate (hereinafter beta-TCP). The porous metal devices that were used to reduce part of the invention to practice are made using orderly oriented wire mesh (OOWM) porous metal coatings, see P. Ducheyne, M. Martens, P. De Meester, J. C. Mulier, "Titanium implants with porous structure for bone ingrowth: a general approach", "Titanium and Its Alloys for Surgical Implants", ed. H. A. Luckey, ASTM, Philadelphia, Pa., 1983; P. Ducheyne, M. Martens, "Orderly oriented wire meshes (OOWM) as porous coatings on orthopaedic implants", I Morphology, J. Clin. Materials, 1 59-67, (1986); P. Ducheyne, M. Martens, "Orderly oriented wire meshes (OOWM) as porous coatings on orthopaedic implants; II: the pore size, interfacial bonding and microstructure after pressure sintering of titanium OOWM", J. Clin. Materials, 1, 91-98 (1986); the method that was used to prepare some of the coatings or powders of the current invention was electrophoretical deposition of CPC films followed by sintering, see, Ducheyne, P., Van Raemdonck, W., Heughebaert, J. C., Heughebaert, M., "Structural analysis of hydroxyapatite coatings on titanium", Biomaterials 7, 97-103 (1986), which are hereby incorporated by reference.
Referring to FIG. 3 and 4, it can be seen that the methods of the present invention result in a ceramic coating which covers substantially all exposed surfaces of the metallic device 10. One of ordinary skill will realize that FIGS. 2 and 3 are generalized representations, not made to any scale. Thus, the methods of the present invention and the ceramic materials disclosed permit porous surfaces, such as the woven wire mesh shown to be electrophoretically coated with a calcium phosphate ceramic material.
Preparation of Coatings
For comparative purposes, a number of different types of coatings were created using the following procedures. CPC powders are either obtained commercially or synthesized. Referring to Table 1, the HA-1 powder is a "Calcium Phosphate Tribasic" (Merck, Darmstadt, Germany). This powder is identical to the HA-1 disclosed previously, see, Ducheyne, P., Van Raemdonck, W., Heughebaert, J. C., Heughebaert, M., "Structural analysis of hydroxyapatite coatings on titanium", Biomaterials 7, 97-103 (1986), which is hereby incorporated by reference. Hydroxyapatite HAp-1 and HAp-2, and tricalciumphosphate apatitic-TCP (ap-TCP) and beta-TCP may be synthesized according to procedures disclosed previously, see, Bonel, G., Heughebaert, J. C., Heughebaert, M., Lacout, J. L., Lebugle, A., "Apatitic Calcium Orthophosphates and related compounds for biomaterials preparation", In Bioceramics: "Material Characteristics vs. in vivo behavior", Ed. P. Ducheyne, J. Lemons, Ann. N.Y. Ac. Sci., 523 (1988), which are hereby incorporated by reference. The two numbers of HAp refer to two different lots.
The powders used and some of their characteristics are summarized in Table 1. The X-ray diffraction (XRD) patterns may be determined using, for example, a Rigaku diffractometer with Cu-K alpha radiation at 45 kV, 35 mA, a scanning rate of 1° 2(theta)/min. and a computerized diffractogram analyzer.
The infrared spectrum is obtained using a Fourier transform infrared spectroscope (FTIR) (Nicolet 5 DxC). Spectra were recorded on 1% powder-KBr mixtures in the diffuse reflectance operational mode.
A calcination, which, however is not wanted or necessary to make the ceramic products of the present invention, typically for 1 hour at 900° C. in air, was performed on some of the powders used for comparison purposes. One of the effects of this step is to substantially remove adsorbed water.
The porous coated specimens used to generate the accompanying data were Ti-6A1-4V alloy plates, 3×10×10 mm, with a commercial purity (c.p.) Ti, orderly oriented wire mesh pressure sintered as described previously, see, P. Ducheyne, M. Martens, "Orderly oriented wire meshes (OOWM) as porous coatings . . . ", supra. The wire mesh was a 16 mesh size twill weave of 0.50 mm diameter wire, Id. The composition of the Ti alloy plate fell within the specifications of ASTM standard F-136. Prior to the electrophoretic deposition the metal specimens were ultrasonically cleaned in acetone, immersed for 10 sec. into a 2% HF+20% HNO 3 aqueous solution, and subsequently rinsed in distilled water.
The CPC coatings were electrophoretically deposited from a 3% suspension of the powders in isopropanol. A 10 mm distance between the lead anode and the cathodic metal specimen was used. The electrophoretic yield on dense or porous coated metal substrates was determined for electrical fields between 60 and 100 V/cm and time of deposition from 10 to 60 sec. Before applying the voltage, the suspensions were ultrasonically stirred in order to break the powder particle clusters. All metal substrates were weighed prior to and subsequent to the deposition process.
Any thermal treatment of the CPC subsequent to electrophoresis, was carried out in vacuum and at relatively low temperatures, in order to minimize the effect on the mechanical properties of the underlying metal. Typical parameters were 925° C., 2 hours, 10 -6 to 10 -7 torr and FTIR characterization studies subsequent to deposition and sintering, if any, were made on either the deposited coatings or scraped off powders respectively.
In view of their intended in vivo use, the assessment of stability in simulated physiological solutions was determined first. Specifically, a solution devoid of calcium and phosphate ions, i.e., a 0.05M tris-(hydroxy)methylaminomethane - HC1buffered solution (pH-7.3 at 37° C.), was chosen and both the dissolved calcium and the weight loss due to debonding of the coating as a function of immersion time were measured. The CPC coatings were obtained starting from HA-1 powder exclusively. The coatings were deposited at 90 V for 60 sec. A 1 mg/1 ml coating weight to solution volume was used, i.e., specimens with a 10 mg coating were immersed in 10 ml of solution contained in 23 mm diameter polystyrene vials. The vials were placed onto a shaker in a water-jacketed incubator. For each time of immersion four separate specimens were used. As controls, solutions without specimens and solutions with as received HA-1 powder were used. Similarly, four samples were used for each immersion time. At the end of each immersion time, the specimens were dried and weighed immediately.
The amount of calcium eluted from each of the specimens was measured in triplicate by flame atomic absorption spectroscopy (AAS) Standard solutions of 0.1, 0.5, 1, 2, 5, and 10×10 -3 mg/ml of calcium were made from a 1,000 mg/ml stock solution of calcium with 1% by weight of lanthanum chloride.
The specific areas of the powders and CPC coatings on porous Ti used were measured by the B.E.T. technique on a Quantasorb, Quantachrome instrument (Greenvale, N.Y.). The morphology of the powders, and the coatings prior to and as a result of the immersion tests was analyzed using scanning electron microscopy (Philips SEM 500, Eindhoven, The Netherlands). All powders, including those used for comparative purposes only and which are not an object of the present invention were prepared for S.E.M. analysis by suspending them ultrasonically in the isopropanol solution (5 mg/30 ml isopropanlol). A droplet of the suspension subsequently was dripped onto the polished aluminum SEM-specimen holder. This technique allowed the powders to be visualized as particles the way they were in solution, and not as clusters that these particles usually form.
The characteristics of the various powders, some of which were only used for comparative purposes, are summarized in Table 1. The Ca/P atomic ratio was determined by X-Ray diffraction. The specific surface area values were either measured before or determined for other syntheses using identical synthesizing procedures.
As indicated in Table 1, the Ca/P ratios of HA-1, HAP-1 and -2, and TCP were 1.61, 1.67, 1.67 and 1.47 respectively. Thus HA-1 is a Ca-deficient, non-stoichiometric apatite, corresponding to the formula Ca 10-x (HPO 4 ) 6 (OH) 2-2x . The HAp-1 and -2 has a perfect hydroxyapatitic stoichiometry and therefore is used to assess the effects of a departure from stoichiometry associated with HA-1. The Ap-TCP powders were used in view of the combination of an apatitic structure with a TCP stoichiometry. The infrared spectra prior to and after calcination of HA-1, HAp-1 and TCP further support the X-Ray diffraction identifications. A broad band is observed in the 3000-3600 cm -1 range which is indicative of the stretching vibration of the hydroxyl ions in the adsorbed water, and peaks seen at 875, 1412 and 1455 cm -1 are due to the presence of carbonate groups. Prior to calcination, the hydroxyl peaks at 630 and 3570 cm -1 observed are small; however, they are considerably more intense after calcination. Furthermore, subsequent to calcination of HA-1, two characteristic peaks for beta-TCP were observed: 940 and 970 cm -1 . Thus the calcination produces a full crystallization of the hydroxyapatite and a partial transformation to beta-TCP in HA-1.
The infrared spectra of HAp-1 indicate that it is a poorly crystallized apatite with a considerable amount of adsorbed water prior to, but a pure hydroxyapatite subsequent to, calcination. The IR spectrum prior to calcination shows a very small OH peak at 3570 cm -1 , a very strong NO 3 - band at 1390 cm -1 and a broad band indicative of adsorbed water in the 3000-3600 cm -1 range. Subsequent to calcination, the OH-peak appears larger, the NO 3 peak disappeared and the two bands at 1040 and 1090 cm -1 specific for the nu-3 stretching vibrations of the PO 4 group in hydroxyapatite have become distinct. Thus, in conjunction with the X-Ray diffraction data, the infrared results indicate that HAp-1, calcined, is a well crystallized stoichiometric anhydrous hydroxyapatite.
The infrared spectrum of the TCP shows it is a poorly crystallized apatic structure prior to heating. There is a broad band indicative of adsorbed water in the 3000 to 3600 cm -1 range. The subsequent calcination step produces the strong peaks at 940 and 970 cm -1 characteristic of beta-TCP. Yet, there are also traces of beta-C 2 P 2 O 7 as revealed by the small peaks or shoulders at 570, 725, 1026, 1106, 1187 and 1212 cm -1 .
A comparative analysis of the electrophoretic yield, i.e., whether or not CPC powders can be electrophoretically deposited follows from Table 2. This table summarizes the coating weight for one condition of electrophoresis (100 V/cm for 60 sec.) 1 for all dissimilar powders of the study, i.e., HA-1, HAp-1 and Ap- or beta-TCP. Table 2 also represents the water content and the current density during the electrophoresis. It follows from this table that both HAp-1, non calcined and Ap-TCP, which is also a non-calcined powder, cannot be deposited. The weight of the deposit is virtually zero. Calcination produces, among other effects, the elimination of the adsorbed water. Subsequent to this heat treatment both powders can be deposited, as is indicated by the coating weight. Since irrespective of composition or crystal structure, deposition is both possible or excluded, it would therefore follow from these data that the adsorbed water interferes with the electrophoretic transport. Yet the HA-1 powder contains some adsorbed water and, as shown in Table 1, it does electrophorectically deposit. Thus, there is a critical concentration of adsorbed water above which electrophoretic deposition is not possible. This critical value is probably about 5%, considering that the non-stoichiometric HA-1 powder can still be deposited with a 4.8% water content. With too high a water content the adsorbed water becomes sufficiently accessible at the particle surface immersed in the alcohol solution and the electric energy is consumed in a hydrolysis reaction and no longer in particle transport.
Specific surface areas varied by an order of magnitude among the powders that can be deposited (see Table 1). Therefore, this parameter does not appear to exert a predominant effect. Neither does the morphology of the particles affect the outcome of the electrophoretic deposition process substantially.
HA-1 powder was used to establish the relationship between the electrophoretic deposition parameters (time, voltage) and the coating thickness. A given thicknesses can be obtained in a shorter time when a higher voltage is applied. Obviously, porous coated surfaces required longer deposition times than smooth titanium specimens for similar deposit thicknesses. A uniform thickness of the deposit in the porous coating cannot be achieved with thin coatings (<5×10 -3 mm) and with higher voltage gradients (>105 V/cm).
Table 3 summarizes the chemical compositions and crystal structures of the CPC powders and coatings for which HA-1 and HAp-1 were the starting powders. For the sake of convenience, some of the as-received characteristics reported above also are included in this table. The following symbols are used:
AR: as received
C: Calcination (900° C., 1 hour, air, furnace cooling)
ED: electrophoretic deposition (90 V/cm, 60 sec.)
VT: heat treatment in vacuum (10 -7 torr) without underlying Ti substrate (925° C., furnace cooling under vacuum); the subscript indicates the hours at temperature.
VS: sintering in vacuum (10 -7 torr) with an underlying Ti substrate (925° C., 2 hours, furnace cooling under vacuum)
When the pure hydroxyapatite is vacuum treated at 925° C. without an underlying Ti substrate the XRD pattern indicates it is a highly crystalline apatic structure. The analysis of the FTIR spectrum then indicates it is an oxyhydroxyapatite material. Specifically the nu-4 vibration of PO 4 in the 550-600 cm -1 interval, and the absence of the weak presence of the 3570 cm -1 and 630 cm -1 OH-absorption bands provide strong evidence for the presence of a partially, if not nearly fully dehydroxylated apatitic structure Ca 10 (PO 4 ) 6 (OH) 2-2y O y [] y with the symbol [ ] representing a vacancy.
The time of vacuum treatment, i.e., 8 or 24 hours, does not yield a meaningful difference; qualitatively, the same structures are identified.
When the pure HAp (i.e., HAp1-C) is electrophoretically deposited onto the titanium substrate, removed from it, and heat treated (without an underlying Ti substrate) the structural findings do not change. That is, the electrophoretic deposition in isopropanol does not affect the structure of the CPC powder.
When the pure HAp (i.e., HAp1-C) is, however, deposited and vacuum sintered onto the underlying titanium substrate, it transforms to a mixture of oxyhydroxyapatite and tetracalcium phosphate. The latter phase is formed because the underlying titanium substrate easily attracts phosphorous. Therefore, with a reduced concentration of P, the Ca to P ratio increases from its initial value of 1.67, eventually resulting in a partial transformation to tetracalcium phosphate.
The structural and compositional changes that occur in CPC that are not pure hydroxyapatite do not necessarily differ from those occurring in the pure hydroxyapatite. This is in particular true when as the starting compound for electrophoresis, vacuum treatment or vacuum sintering a mixture of pure hydroxyapatite and some other compound is used. This can be done by using HA-1 in the calcined condition (HA-1 - C), since this powder is a mixture of pure hydroxyapatite and beta-tricalcium phosphate. Subjecting this powder to the same treatment, i.e., electrophoretic deposition and vacuum sintering, as the pure hydroxyapatite (HAp-1, C), produces the same qualitative transformations: that is, the hydroxyapatite transforms to a mixture of oxyhydroxyapatite and tetracalcium phosphate. In addition, however, the presence of beta-tricalciumphosphate must be considered; and this compound partially transforms to alpha-tricalciumphosphate.
The ceramics and coatings of the present invention are generally unstable, do not have substantial amounts of tetracalciumphosphate, and exhibit high dissolution rates. They consist essentially of oxyhydroxyapitite, alpha-TCP and beta-TCP. Whereas sintering the commercially obtained CPC powder HA-1 in the calcined condition on titanium does not produce principally different results from the experimentation with pure hydroxyapatite (HAp-1), the eventual structure with the non-calcined commercial powder HA-1 diverge markedly, however, the mechanisms are still the same. HA-1, non-calcined, is a Ca-deficient hydroxyapatite. When vacuum treated on a titanium substrate, four concurrent effects take place. First, the effect of calcination itself, i.e., transformation of the Calcium deficient hydroxyapatite to a pure hydroxyapatite and beta-tricalcium phosphate mixture; second, the partial dehydroxylation of the hydroxyapatite to form oxyhydroxyapatite; third, the partial transformation of beta-TCP to alpha-TCP; and fourth, the preferential diffusion of P to the Ti substrate, thereby increasing the Ca to P ratio in the mixture. The first three effects are present in HA-1, AR, VT (i.e., without the underlying metal substrate) and thus the net effect is a transformation to a mixture of oxyhydroxyapatite, beta- and alpha-TCP, as follows from the XRD pattern and FTIR spectrum. Such phase transformation can also be achieved with other processes which subject calcium deficient hydroxyapatite to high temperature and to an atmosphere provoking full or partial dehydroxylation.
With the underlying Ti substrate the average Ca to P ratio of the coating increases from its original value of 1.61. Based upon the experimental observations, the ratio never reaches 1.67 or higher during sintering, since only oxyhydroxyapatite, and beta- and alpha-TCP is observed. Thus, when the CPC coating has a Ca/P ratio prior to sintering of 1.67, the loss of P leads to a mixture of compounds, with a ratio of 1.67 and 2; when the ratio before sintering is below 1.67, e.g., 1.61 it is possible to still obtain a mixture of compounds with respective atomic ratios of 1.5 and 1.67 subsequent to vacuum sintering on titanium. One of ordinary skill in the art will realize that the effect of the underlying titanium on the desired phase transformation in the ceramic will occur regardless of the deposition process used, so long as the reaction time is sufficient and no other substances interfere with the phosphorous diffusion.
As was the case for the pure hydroxyapatite, the electrophoretic deposition does not change the characteristics of the powder: the XRD patterns of HA-1, AR prior to and/or after electrophoretic are identical.
In Vivo Experiments
In order to determine the effects of the various coatings described above on actual bone ingrowth, certain experiments were conducted. The experiments are best understood by referring to the data contained in Tables 4-6. The process of the present invention was carried out using a starting powder, HA1, which is a calcium deficient hydroxyapatite (Merck). CAP 1 is formed by making a composite of 75% HA1 and 25% poly(lactic acid) (% by weight). The composite is deposited by making a suspension in an easily vaporizable solvent (methylene chloride) and dipping a porous metallic specimen into it. CAP 2 is a film formed by electrophoretic deposition. The film is 75×10 -6 meters thick; the deposition process occurred at a potential of 90 V/cm for 60 seconds. CAP 3, a sintered material, was formed using CAP 2 material. The sintering occurred in a vacuum (10 -6 torr, at 925° C. for 2 hours. The type, thickness and other parameters associated with each coating is contained in Table 6, as well as the initial in vitro dissolution rate for each coating.
The results illustrated in Tables 4-6, were obtained using rectangular plugs 10×5×5 mm, possessing an orderly oriented cp (commercial purity) Ti mesh surface coated with the three calcium phosphate films described above: CAP 1, CAP 2, and CAP 3; an uncoated plug served as a control. In vitro dissolution rates were determined by immersion in 0.05M tris physiologic solutions for periods of time ranging from 5 minutes to 24 hours. Table 4 reports the dissolution rates observed. In accordance with the present invention, the coating formed should be relatively unstable. Dissolution rates are an indication of that instability when exposed to physiologic solutions. Coatings of the present invention should exhibit initial dissolution rates under the experimental conditions described above in excess of 15×10 -7 mg/cm 2 .sec, preferably about 60×10 -7 mg/cm 2 .sec, as indicated for CAP 3 coating described in Table 5.
Thirty adult beagle dogs were equally divided into study periods of 2, 4 and 6 weeks. One of each type plug was press fit into the medial and lateral supracondylar region of both hind limbs. Each specimen was pull tested at sacrifice to determine the interfacial bonding. The decohesion and shear strengths and the levels of statistical significance among the various material types are contained in Tables 4 and 5. One of each type plug was press fit into the medial and lateral supracondylar region of both hind limbs according to a predetermined randomized order. Radiographs were taken pre- and post-operatively and at sacrifice. Each implant underwent mechanical pullout testing to determine ultimate shear strength. A randomized block ANOVA followed by a Student-Newman-Keuls test compared the groups. No implants became infected. On radiographic review, no lucencies were present at the bond/coating interface. Initial dissolution rates for CAP 1, CAP 2, and CAP 3 were 2.7×10 -7 , 5.5×10 -7 and 6×10 -6 mg/cm 2 s respectively. Ultimate shear strength increased both over time and with increasing dissolution rates (see Table 4). The uncoated mesh strengths were 2.7, 3.3. and 3.6 MPA for the 2, 4 and 6 week time periods. CAP 1 strengths were 2.1, 2.8 and 4.2 MPA which were not statistically different from the uncoated mesh. CAP 2 strengths were 3.6, 4.8 and 5.2 MPA. CAP 3 strengths were 4.1, 5.6 and 6.6 MPA. At 6 weeks, the CAP 3 mesh was significantly stronger than the CAP 2 mesh.
As seen from Tables 4-6, the CAP 3 coating, which has the highest dissolution rate, also promotes the best mechanical bond. This dissolution of the coating acts by providing a local source of ions essential for tissue calcification. The CAP 3 coating is also quite uniform and complete, having been deposited in accordance with the preferred processing parameters discussed above (and used for the comparative coatings as well). The CAP 1 coating is not acceptable, since it results in lower initial bonding strength compared to the porous metal coating without the ceramic used as a control. The CAP 2 coating is acceptable and demonstrates the advantages of using the preferred embodiment coating method.
As seen from the above, superior prosthetic surfaces are achieved by using porous titanium coatings which are uniformly coated with ceramic films of specific composition, under controlled deposition procedures. The resulting CAP 3 films are relatively unstable, having higher dissolution rates which result from the fact that they are essentially free of tetracalcium phosphate, and instead consist essentially of alpha and beta tricalcium phosphate, and oxyhydroxyapatite.
While the present invention has been described in connection with prothesis implantation, other major applications of the calcification enhancement materials of the present invention is bone augmentation. A press fit prosthesis needs to attract calcified tissue as quickly as possible in those areas where bone is not present. This absence of bone can be the result of surgical destruction or of prior bone trauma. In the mandibula or the maxilla, loss of bone mass follows from full or partial loss of dentition. The bone can be rebuilt with calcification promoting substances. Such rebuilding can be undertaken without, or alteratively with proteins that are derived from bone tissue. Such proteins can be made in larger quantities by genetic engineering techniques if necessary. Such proteins may trigger the formation of the organic matrix of bone in non bone-tissue sites. Thus, when the underlying pathology is such that the bone metabolism is seriously affected, a trigger is needed, supplemented with a substance that enhances the calcification and the overall rate of bone formation. These instances can be situations of larger mandibular or maxillar bone loss, due either to pathology (cysts), absence of dentition, filling of extracted tooth root sites or periodontal lesions. Additional applications for the combined use of biological growth factors and calcium phosphate ceramics are conditions of traumatic bone loss and the absence of normal healing processes like in non-unions. Yet another application could be the surgical repair of osteoporotic bone loss and concomitant bone collapse. Thus, those of ordinary skill in the art will recognize that the ceramic coatings of the present invention can be removed from the underlying metallic substrate on which they are formed, and be injected in powdered form or otherwise introduced into proximity with bony tissue, to substrate on which they are formed, and be injected in powdered form or otherwise introduced into proximity with bony tissue, to promote its growth.
TABLE 1__________________________________________________________________________Characteristics of the starting CPC powders Water NO.sub.3.sup.2- CO.sub.3.sup.2- Chemical Ca/P content content content SSADemomination Snythesis formula ratio % (by wt.) % (by wt.) % (by wt.) m.sup.2 /g__________________________________________________________________________HA1 p* CA.sub.10-x 1.61 4.8 -- 1.5 76.0.sup.1As rec'd (HPO.sub.4).sub.6-x (OH).sub.2-xHA1c P* + C*** HA + " -- -- -- n.d.(calcined) β -TCP mixtureHAP1 P* + L*** CA.sub.10 (PO.sub.4).sub.6 1.67 9.9 -- -- 42.sup.1 (OH).sub.2 P + L + C*** CA.sub.10 (PO.sub.4).sub.6 " 0 3.7.sup.2 (OH).sub.2HAP2-A P + L CA.sub.10 (PO.sub.4).sub.6 1.67 15.6 -- -- (OH).sub.2AP-TCP P + L CA.sub.9 (HPO.sub. 4) 1.47 11 -- -- 64.sup.2 (PO.sub.4).sub.5 OHβ-TCP P + L + C CA.sub.9 (PO.sub.4).sub.6 + 0 -- -- 4. traces β- 4..sup.2 CA.sub.2 P.sub.2 O.sub.7__________________________________________________________________________ p* precipitation L** lyophilization C*** calcination 900° C., 1 hr, 01iL n.d.: not determined .sup.1 Ducheyne, P., Van Raemdonck, W., Heughebaert, J. C., Heughebaert, M. "Structural analysis of hydroxyapatite coatings on titanium". Biomaterials 7, 97-103 (1986). .sup.2 Bonel, G., Heughebaert, J. C., Heughebaert, M., Lacout, JL., Lebugle, A. "Apatitic Calcium Orthophosphates and related compounds for biomaterials preparation". In Bioceramics: "Material Characteristics vs. in vivo behavior" Ed. P. Ducheyne, J. Lemons, Ann. N.Y. Ac. Sci., 523 (1988).
TABLE 2______________________________________Electrophoretic deposition results for variousCPC powders deposited at 100 V/cm for 60 sec. Water Current Coating Content density + weightPowder % (by weight) (mA/cm.sup.2) (mg/cm.sup.2)______________________________________HA1-(nc*) 4.8 15-30 10 ± 2HAp-1 (nc*) 9.9 >1000 0HAp-1 (c**) 0 <20 10Ap-TCP (nc*) 11 19-21 0β-TCP (c**) 0 <15 15______________________________________ Notes: (*) nc: noncalcined (**) c: calcined +: the current density decreases during deposition, therefore only a rang is indicated
TABLE 3______________________________________Characteristics of the treated CPC powders and coatings.Basepowder treatment structural characteristics______________________________________HAp-1 AR (precip poorly crystalized and hydroxyapatite (single lyophilized phase material)HAp-1 AR + C pure hydroxyapatite (single phase material) AR + C + VT.sub.8 . . . oxyhydroxyapatite (single phase material) AR + C + VT.sub.24 . . . oxyhydroxyapatite (single phase material) AR + C + ED + VS . . . oxyhydroxyapatite, tetracalciumphosphateHA1 AR + C hydroxyapatite (HA) + β-tricalcium - phosphate(β-TCP) (two phase material) . . . oxyhydroxyapatite + tetracalciumphosphate + α-TCPHA1 AR Ca-deficient hydroxyapatite (one phase material) AR + ED Ca-deficient hydroxyapatite (same as AR) AR + VT.sub.2 . . . oxyhydroxyapatite with traces of α-, β-TCP AR + ED + VS . . . oxyhydroxyapatite with α-, β-TCP + --______________________________________
TABLE 4__________________________________________________________________________initial in vitro Ca dissolution rates; in vivobonding at different times after implanation (n = 10) initial in vitro in vivoceramic Ca dissolution rate interfacial decohesion shear strength (MPa + S.D.)coating (10.sup.7 × mg/cm.sup.2 · s) 2 wks 4 wks 6 wks__________________________________________________________________________none: -- 2.68 (1.44) 3.34 (0.40) 3.61 (0.72)(porous metal only)CAP 1 2.7 2.17 (0.96) 2.83 (0.19) 4.26 (0.52)CAP 2 5.7 3.59 (1.00) 4.83 (0.49) 5.24 (0.72)CAP 3 60.0 4.13 (1.43) 5.62 (0.44) 6.62 (0.66)__________________________________________________________________________
TABLE 5______________________________________ Time of implantation (weeks)Pairs 2 4 6______________________________________no coatingvs CAP 1 <0.2 <0.2 <0.5CAP 2 0.1 0.05 0.05CAP 3 0.005 0.01 0.001CAP 1vs CAP 2 0.005 0.002 0.1CAP 3 0.001 0.001 0.001CAP 2vs CAP 3 0.2 0.2 0.05______________________________________
TABLE 6______________________________________ CAP 1 CAP 2 CAP 3______________________________________initial in vitro 2.7 5.5 60dissolution rate(10.sup.-7 · mg · cm.sup.-2 · sec.sup.-1)in vitro coating 0.2 52.7 13.3degradation* (%)coating composition poly (lactic calcium oxyhy- acid)-calcium deficient droxy- deficient apatite apatite, apatite α- and composite β TCPthickness (μm) 50 75 75specific surface area / 55.0 9.2(m.sup.2 /g)______________________________________ *coating weight loss due to particle release after 1 hr. of immersion | Improved ceramics which promote bone ingrowth are disclosed. The coating of the present invention consists essentially of oxyhydroxyapatite, and alpha- and beta-tricalcium phosphate. Methods of making and using the ceramics are also disclosed. The present invention uses a microscopically powdered form of calcium-phosphate materials and electrophoretic deposition to create ceramics having significantly higher dissolution rates than previous materials. By agitating the electrophoretic solution, agglomeration is prevented and a uniform coating is achieved. Thus, the present invention presents both improved ceramic materials and novel methods of depositing them uniformly upon metal surfaces, such as titanium wire mesh. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and incorporates herein by reference Japanese Patent Application No. 2002-38879 filed on Feb. 15, 2002.
FIELD OF THE INVENTION
[0002] The present invention relates to an adjustment-circuit embedded semiconductor sensor and a torsion bar type torque sensor system that uses the adjustment-circuit embedded semiconductor sensor.
BACKGROUND OF THE INVENTION
[0003] A conventional torsion bar type torque sensor system uses a permanent magnet as a magnetic flux generator, so that residual magnetic flux density variation due to temperature variation adversely affects on sensitivity of a torque sensor. Deviation in a size, kind, and material characteristic of the permanent magnet results in fluctuation of the sensitivity and an offset value (zero point output) of the torque sensor.
[0004] The conventional torsion bar type torque sensor system is therefore equipped with a temperature sensor such as a thermistor around the permanent magnet. According to temperature detected by the temperature sensor, adjustment for the fluctuation is executed in a circuit outside the sensor.
[0005] However, the above method, so-called an external adjustment method, involves additional installment of a separated external adjustment circuit for the adjustment or enlargement of a control section of the torque sensor system when the adjustment circuit is added to the control section of the torque sensor system. This results in increasing a size and cost of the torque sensor system. Furthermore, replacement of the sensor part itself due to its breakdown invalidates previous adjustment data in the above adjustment circuit. This therefore poses replacement of the entire torque sensor system including the external adjustment circuit, which eventually increases cost in maintenance. The above problem occurs not only in the torsion bar type torque sensor system but also in a usual sensor system.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide an adjustment-circuit embedded semiconductor sensor and a torsion bar type torque sensor system that adopt the adjustment-circuit embedded semiconductor sensor.
[0007] To achieve the above and other objects, an output-adjustment embedded semiconductor sensor is provided with a plurality of sections, which are integrated in the sensor. Here, a detecting section detects at least either of a physical amount and a chemical amount as an electric amount. A thermal detecting section detects a temperature. A non-volatile rewritable memory section rewritably stores adjustment data to adjust an error of the detected electric amount. An adjustment computation section for outputting an adjusted signal after offset adjustment of the detected electric amount, sensitivity adjustment and temperature adjustment, based on the detected temperature and stored adjustment data.
[0008] Namely, the semiconductor sensor is formed of a monolithic one-chip IC including the above sections, so that it internally executes the offset adjustment, sensitivity adjustment and temperature adjustment. Breakdown of the sensor therefore involves only replacement of the sensor itself without any replacement nor additional adjustment of the external circuit, which results in simplifying maintenance of the sensor system.
[0009] It is preferable that the semiconductor sensor is further provided with an operation control section for externally receiving an operation command and subsequent adjustment data. Here, the operation control section writes the subsequent adjustment data in the non-volatile rewritable memory when the operation command is a writing command. This enables writing of the adjustment data to the non-volatile rewritable memory to be easy.
[0010] It is furthermore preferable that when the operation command is a writing-prohibiting command, the operation control section prohibits the writing of the subsequent adjustment data in the non-volatile rewritable memory. This prevents noise or other abnormal events from rewriting false adjustment data to the non-volatile rewritable memory.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:
[0012] FIG. 1 is an axial section view of a torque sensor system according to a first embodiment of the present invention;
[0013] FIG. 2 is a disassembled perspective view of the torque sensor system;
[0014] FIG. 3 is a block diagram of a magnetometric sensor IC of the torque sensor system;
[0015] FIG. 4 is a schematic block diagram of a lock section of the magnetometric sensor IC;
[0016] FIG. 5 is a block diagram of a magnetometric sensor IC according to a second embodiment;
[0017] FIG. 6 is a block diagram of a magnetometric sensor IC according to a third embodiment; and
[0018] FIG. 7 is a disassembled perspective view of a torque sensor system according to a fourth embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0019] (Structure)
[0020] A torque sensor system as a first embodiment of the present invention is used for, e.g., electric power steering equipment. Referring to FIG. 1 , the torque sensor system is disposed between an input shaft 2 and an output shaft 3 , both of which compose a steering shaft, detects steering torque applied to the steering shaft.
[0021] The input and output shafts 2 , 3 are, relatively rotationally and torque-transmittably, combined by a torsion bar 4 . A ring magnet 5 is fixed by fitting it together with the edge of the input shaft 2 , while a magnetic yoke 6 is fixed to the edge of the output shaft 3 .
[0022] The circumferential area of the ring magnet 5 is magnetized in alternate poles at a predetermined circumferential pitch. The magnetic yoke 6 has two magnetic yoke halves 6 A, 6 B that are fixed coaxially with the output shaft 3 at a predetermined spacing. The magnetic yoke halves 6 A, 6 B, made of a soft magnetic member, are roughly L-shaped and roughly U-shaped, respectively, in an axial section as shown in FIG. 1 . They have teeth that surround the ring magnet 5 , at a predetermined gap relative to the circumference of the ring magnet 5 , and axially extend at a predetermined circumferential pitch. They also have circular ring plates that radially-outwardly extend from the bottom edges of the teeth, and cylinder hollows that axially extend from the circumferential edges of the circular ring plates. The teeth of the magnet yoke halves 6 A, 6 B are circumferentially and alternately disposed. Magnetic flux from N pole of the ring magnet 5 reaches S pole of the ring magnet 5 via a circuit. This circuit travels through teeth of one of the yoke halves 6 A, 6 B that radially-outwardly adjoins the N pole, the cylinder hollow of the one of the yoke halves 6 A, 6 B, the cylinder hollow of the other of the yoke halves 6 A, 6 B, and the teeth of the other of the yoke halves 6 A, 6 B.
[0023] A magnetometric sensor IC 7 is fixed in a stationary state within the axial spacing between the magnetic yoke halves 6 A, 6 B, for detecting the magnetic field variation in the spacing. Pins 8 are for fixing the torsion bar 4 .
[0024] In the above structure, application of torque to the input shaft 2 leads to torsion in the torsion bar 4 , so that the torque is transmitted to the output shaft 3 . Occurrence of relative rotational position difference (i.e., relatively rotated angle) between the ring magnet 5 and the magnetic yoke 6 causes variation in the magnetic flux density between the cylinder hollows of the magnetic yoke 6 . This variation of the magnetic flux density is externally outputted.
[0025] The magnetometric sensor (M sensor) IC 7 will be explained below, referring to FIG. 3 . The magnetometric sensor IC 7 that is integrated to one chip includes the following: three terminals of a voltage source terminal 7 A, a ground (GND) terminal 7 B, and an output terminal 7 C; a thermal detector 7 E for detecting temperature in a vicinity of the magnetometric sensor IC 7 ; an oscillator 7 F for providing reference clock to each section of the IC; a magnetometric sensor 7 G such as a hall element for detecting magnetic flux density; an analog/digital (A/D) converter section 7 H for converting output analog voltage of the magnetometric sensor 7 G to a digital value; a non-volatile memory 7 N for storing adjustment data, a computation section 7 I for computing adjustment of digital signals outputted from the A/D converter section 7 H based on data stored in the non-volatile memory 7 N; a digital/analog (D/A) converter section 7 J for reconvert, to analog voltage, the digital values of the computed result in the computation section 7 I; a buffer 7 K for externally outputting the reconverted analog voltage; a logic section 7 L for determining computing operation of the computation section 7 I based on power voltage applied to the voltage source terminal 7 A; and a lock section 7 M for disabling rewriting to the non-volatile memory 7 N based on the determination of the logic section 7 L.
[0026] The logic section 7 L detects voltage level applied to the voltage source terminal 7 A to determine whether the voltage level corresponds to usual measurement operation or writing operation in the non-volatile memory 7 N. When the writing operation is determined, the logic section 7 L digitalizes voltage variation of the voltage source terminal 7 A to obtain digital signals. The digital signals are written in the non- volatile memory 7 N through the lock section 7 M. The logic section 7 L has a comparator for determining the power voltage level. When the usual measurement operation is determined, the lock section 7 M commands prohibition of the writing in the non- volatile memory 7 N, based on a command from the logic section 7 M.
[0027] The computation section 7 I, the logic section 7 L, and the lock section 7 M are formed from well-known generalized circuitry. They are also obviously realized from usual hardware logic circuitry or microcomputer software, so that detail explanation about the circuitry is not described hereunder.
[0028] (Usual Detecting Operation)
[0029] A usual operation voltage (e.g., 5V) is applied to the voltage source terminal 7 A, so that each circuit of the magnetometric sensor IC 7 is supplied with necessary power (electric voltage, electric current).
[0030] The oscillator 7 F provides each circuit with pulse signals of a constant cycle as the reference clock. An analog voltage value of the magnetic flux density information outputted from the magnetometric sensor 7 G is converted by the A/D converter section 7 H to digital values to be transmitted to the computation section 7 I. A voltage value of temperature information outputted from the thermal detector 7 E is transmitted to the magnetometric sensor 7 G and the computation section 7 I. A measurement signal, indicating that a usual measurement should be executed at present, outputted from the logic section 7 L is transmitted to the computation section 7 I. The computation section 7 I, based on the above information and parameters stored in the non-volatile memory 7 N, adjusts the magnetic flux density information detected by the magnetometric sensor 7 G to digital information to transmit to the D/A converter section 7 J. The digital information is converted by the D/A converter section 7 J to analog voltage to externally transmit via the buffer 7 K.
[0031] (Non-detecting Operation)
[0032] An unusual voltage (e.g., 6V and more) other than the usual operation voltage is applied to the voltage source terminal 7 A longer than a predetermined period, so that the logic section 7 L detects the unusual voltage to determine that a program mode is commanded. The logic section 7 L then reads out binarized voltage variation patterns (e.g., high-8V, low-6V) to determine an external command. The external command includes a rewriting command for rewriting the data stored in the non-volatile memory 7 N, a data-reading command for commanding the computation section 7 I to externally output the data stored in the non-volatile memory 7 N via the buffer 7 K, and a lock command for retaining the data stored in the non-volatile memory 7 N. When the logic section 7 L determines the lock command, it commands the lock section 7 M to prohibit rewriting of the non-volatile memory 7 N. The installment of the lock section 7 M prevents wrong rewriting in the non-volatile memory 7 N even when voltage variation due to an external disturbance is wrongly determined to be the rewriting command.
[0033] Referring to FIG. 4 , the lock section 7 M is typically formed between an R/W terminal of the logic section 7 L and an R/W terminal of the non-volatile memory 7 N. The lock section 7 M includes a transfer gate or a MOS transistor 71 forming an inverter circuit, and a circuit for intermittently controlling the MOS transistor 71 based on a potential state inputted through a one-time writable non-volatile memory (PROM) such as a fuse ROM. When the logic section 7 L blows out the PROM to irreversibly turn off, the transfer gate is set to off to prohibit the logic section 7 L from writing in the non-volatile memory 7 N. By contrast, writing capability can be once again possible by other methods such as ultra-violet erasure other than the voltage signal method.
[0034] (Effect)
[0035] A conventional torque sensor system is controlled with a detecting signal of a torque sensor. The conventional torque sensor system is composed of the torque sensor, a torque sensor unit as a mechanical part, and an electronic control unit (ECU) that computes, with the output signal from the torque sensor unit, a control signal to output. Adjustment of a torque sensor characteristic is executed in the ECU by adjusting, before shipment of the system, an adjustment circuit attached to the ECU or by storing adjustment information in a non-volatile memory of the ECU. Breakdown of the above torque sensor unit involves entire replacement of the torque sensor system on site or additional adjustment in the ECU after the partial replacement. Breakdown of the ECU also involves the same procedures similar to that in the breakdown of the torque sensor unit. A lot of recovery work is therefore imposed to the above breakdown.
[0036] In the embodiment, the magnetometric sensor, constituting the torque sensor, has the integrated non-volatile memory and various processing circuits, so that offset adjustment, sensitivity adjustment, and temperature characteristic adjustment are executed within the torque sensor. When the torque sensor is broken, the recovery work involves only replacement of the broken torque sensor without adjustment in the ECU. This results in credibly decreasing time and cost of the recovery work. When the ECU is broken, only replacement of the ECU is involved without any additional adjustment in the replaced ECU. Decrease of components in the torque sensor leads to high reliability. Adjustment information can be modified and stored according to other system specifications, so that flexibility to various usages is enhanced.
Second Embodiment
[0037] Referring to FIG. 5 , in a second embodiment, a serial output section 70 is adopted for executing serial output of digital signals as substitution of the D/A converter section 7 J and buffer 7 K shown in FIG. 3 .
[0038] In this embodiment, adoption of the serial output can prevent several problems resulting from the analog voltage output such as an error from voltage reduction due to wiring resistance, and adverse effect from electromagnetic noise. Additionally, in an ECU that receives the digital signal outputted from the serial output section 70 , adverse effect from high frequency noise is decreased through a low-pass filter without decreasing accuracy of the digital signals.
Third Embodiment
[0039] Referring to FIG. 6 , in a third embodiment, an analog computation circuit 7 P is adopted as substitution of the computation section 7 I shown in FIG. 3 . The analog computation circuit 7 P is formed from various computation circuits using operational amplifiers for executing computation commanded by the logic section 7 L. Based on the substitution, an output signal is converted, by a D/A converter section 7 J, to analog voltage to output to the analog computation circuit 7 P. In this embodiment, adoption of the analog computation circuit 7 P leads to deletion of the A/D converter section 7 H shown in FIG. 3 , so that simple circuitry and rapid computation are realized.
Fourth Embodiment
[0040] Referring to FIG. 7 , in a fourth embodiment, a pair of magnetism-collecting rings 9 A, 9 B is added. The pair of the magnetism-collecting rings 9 A, 9 B, made of a soft magnetic member, is for drawing to converge, to one point, magnetic flux that generates from a ring magnet 5 and passes between a pair of two magnetic yoke halves 6 A, 6 B. The magnetism-collecting rings 9 A, 9 B are fixed in stationary state at a predetermined narrow gap relative to circumferential edges of circular ring plates of the magnetic yoke halves 6 A, 6 B, respectively. The magnetism-collecting rings 9 A, 9 B have magnetism-collecting plates 9 C, 9 D, respectively. The magnetism-collecting plates 9 C, 9 D, made of a soft magnetic member, extend radially-outwardly at predetermined points while facing with each other with a predetermined axial spacing. The predetermined axial spacing between the plates 9 C, 9 D is much narrower than that between the rings 9 A, 9 B. The axial spacing between the rings 9 A, 9 B are set to be adequately large, while the magnetic yoke halves 6 A, 6 B have no cylinder hollows shown in FIGS. 1 and 2 .
[0041] Under the above structure, the magnetic flux enter one of the magnetism-collecting rings 9 A, 9 B from adjoining one of the annular ring plates of the yokes 6 A, 6 B. It then proceeds to the other of the manetism-collecting ring 9 A, 9 B through the mutual plates 9 C, 9 D. It further proceeds to the other of the annular ring plates of the yokes 6 A, 6 B. Almost all the magnetic flux is therefore converged between the plates 9 C, 9 D, passing through a magnetometric sensor IC 7 that is disposed between the plates 9 C, 9 D. This structure enhances sensitivity of the torque sensor and reduces errors from axial displacement, in comparison with that of the first embodiment shown in FIGS. 1 and 2 . | A torsion bar type torque sensor system is provided with the following: an elastic member that receives a torque and converts the torque to a torsion displacement; a multipolar ring magnet in which N poles and S poles are circumferentially and alternately magnetized; a pair of magnetic yoke halves disposed coaxially with the ring magnet; and a magnetometric sensor that detects magnetic flux generated between the pair of the magnetic yoke halves. The magnetometric sensor is made of a semiconductor that integrates a semiconductor magnetometric sensor, a non- volatile memory, a computation circuit, and an output circuit. This structure provides a torque sensor system that has an excellent maintainability. | 6 |
BACKGROUND OF THE INVENTION
The invention relates generally to piping systems and in particular to a fitting for use with a tubing containment system. Currently, flexible piping, such as corrugated stainless steel tubing, is used in a number of applications requiring primary and secondary containment. Various plumbing as well as local and federal mechanical codes and specifications require that certain types of installations of flexible piping be protected by a secondary containment system. Tubing containment systems exist in the art to contain fluids if the tubing fluids. One existing tubing containment system is disclosed in U.S. Pat. No. 7,004,510, the entire contents of which are incorporated herein by reference. A threaded fitting for use with a tubing containment system is disclosed in U.S. patent application Ser. No. 12/207,626, the entire contents of which are incorporated herein by reference.
SUMMARY
Embodiments of the invention include a fitting for use with metal tubing in a jacket, the fitting comprising: an adapter, the adapter having a tubular member defining a longitudinal passage having a longitudinal axis for fluid flow; a body for receiving the tubing, the body positioned opposite the adapter and aligned with the longitudinal axis; a sealing member positioned between the adapter and the body; a retainer positioned external to the sealing member, the retainer receiving the adapter and receiving the body; a first flange located near the adapter and a second flange located near the body; and a fastener for drawing the first flange and second flange towards each other.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of an exemplary flanged fitting for use in a tubing containment system attached to tubing.
FIG. 2 is a cross-sectional view of the adapter of FIG. 1 .
FIG. 3 is a cross-sectional view of the body of FIG. 1 .
FIG. 4 is an enlarged, cross-sectional view of the ferrule of FIG. 1 .
FIG. 5 is a cross-sectional view of a fitting in an alternate embodiment.
FIG. 6 is an enlarged, cross-sectional view of a portion of FIG. 5 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a cross-sectional view of an exemplary flanged fitting coupled to a tubing containment system. The fitting includes an adapter 100 and a body 200 . Adapter 100 includes a longitudinal through passage 106 to allow fluid (gas, liquid, etc.) to flow. As described in U.S. Pat. Nos. 5,799,989, 6,079,749 and 6,428,052, adapter 100 interacts with a sealing member 300 to compress corrugated tubing between the adapter 100 and sealing member 300 to form a fluid tight seal. Sealing member 300 may be a formed by split ring washers, a collet or other member. Retainer 400 is used to keep the sealing member 300 in place and guide the body into position during use. A ferrule 500 engages the jacket 702 of the corrugated tubing 700 to mechanically secure the jacket 702 to body 200 . Ferrule 500 also creates fluid tight seal against body 200 as described in further detail herein.
FIG. 2 is a cross-sectional view of the adapter 100 of FIG. 1 . Adapter 100 includes a tubular member 102 defining through passage 106 along longitudinal axis 104 . A shoulder 108 extends away from tubular member 102 , and is generally perpendicular to longitudinal axis 104 . Flange 600 contacts shoulder 108 when the fitting is assembled as described herein. A guiding surface 110 tapers from the shoulder 108 , and has an oblique angle relative to the longitudinal axis 104 of the fitting. In an exemplary embodiment, the angle of the guiding surface 110 matches the angle of an inlet surface 402 on retainer 400 . Adapter 100 includes an o-ring groove 112 for receiving an o-ring that seals against the interior of retainer 400 . Adapter 100 includes an adapter sealing surface 114 that contacts the exposed corrugated tubing 700 and compresses the metal tubing 700 between the adapter sealing surface 114 and a sealing surface 302 on sealing member 300 . In an exemplary embodiment, the angle of the adapter sealing surface 114 matches the angle of the sealing surface on sealing member 300 .
FIG. 3 is a cross-sectional view of the body 200 of FIG. 1 . Body 200 includes an o-ring groove 204 formed on an exterior surface of the body at a first body end proximate the adapter 100 . An o-ring may be positioned in the o-ring groove 204 to provide an enhanced seal between the body 200 and the retainer 400 . Body 200 also includes features that provide for venting of fluid in the event of a fluid. Body 200 includes a vent opening 206 that extends through an exterior wall of body 200 . Vent opening 206 provides for egress of fluid leaking from tubing 700 ( FIG. 1 ). Sensors (not shown) may be placed in fluid communication with vent opening 206 for monitoring of leaking fluid.
A ferrule 500 is positioned on a rear end of the body 200 and engages the jacket 702 of tubing 700 ( FIG. 1 ). The ferrule 500 is received in a frusto-conical annular recess 208 on the rear of the body 200 where tubing 700 enters the fitting. The recess 208 has a recess surface having an angle “a” relative to a longitudinal axis of the fitting, 104 . In an exemplary embodiment, angle “a” equals 30 degrees.
FIG. 4 is an enlarged, cross-sectional view of the ferrule 500 of FIG. 1 . Ferrule 500 has a dual tapered surface 502 having a first section 504 and a second section 506 . The first section 504 has a steep angle (e.g., 45 degrees) to define a sharp edge 510 . This edge 510 is driven into the tubing jacket 702 when the fitting is assembled as described in further detail herein. The second section 506 has a more shallow angle “b” (e.g., 20 degrees). By making angle “b” less than angle “a” (on the recess 208 ) the edge 510 of ferrule 500 is driven towards the centerline of the body, into the jacket 702 . Edge 510 engages jacket 702 and provides a mechanical attachment between the body 200 and the jacket 702 . This provides a fluid-tight, mechanical attachment to the jacket 702 to control axial extension of the hose assembly under pressure. Also, the compression of ferrule 500 into the frusto-conical annular recess 208 and also provides a fluid-tight, metal-to-metal seal. Jacket 702 may be similar to that described in U.S. patent application Ser. No. 12/207,626.
In assembling the fitting to the tubing 700 , the tubing 700 is fed through flange 650 , ferrule 500 , and body 200 . The distal end of tubing 700 has the jacket 702 removed to expose at least one valley of the corrugated tubing 700 . Corrugated tubing 700 has an exterior surface of undulating peaks and valleys. Sealing member(s) 300 is placed in an exposed valley of corrugated tubing 700 . The tubing 700 is pulled back through the body 200 until the sealing member 300 contacts a shoulder 220 .
Retainer 400 is slid over the sealing member 300 . Adapter 100 is inserted into the retainer 400 , guided by guiding surface 110 coacting with inlet surface 402 . Flange 600 is positioned around tubular member 102 . Fasteners (e.g., bolts) 800 pass though openings 602 in flange 600 and engage threads 652 in flange 650 . In exemplary embodiments, four bolts are used.
As the bolts 800 are tightened, adapter sealing surface 114 contacts the exposed corrugated tubing 700 and compresses the metal tubing 700 between the adapter sealing surface 114 and a sealing surface 302 on sealing member 300 . As flange 600 and flange 650 are drawn towards each other, the compression of the metal tubing 700 between the adapter sealing surface 114 and the sealing surface 302 folds the metal tubing 700 to form two layers of metal between adapter sealing surface 114 and sealing surface 302 . This defines a metal-to-metal seal between the adapter 100 and tubing 700 .
Further, as the bolts 800 are tightened, the ferrule 500 is driven into frusto-conical annular recess 208 in body 200 . As the angle “a” of the recess 208 is greater than the angle “b” of second section 506 of tapered surface 502 , the ferrule 500 is driven into the jacket 702 . The edge 510 of ferrule 500 engages the jacket 702 to provide a secure fluid tight, mechanical connection. The compression of the ferrule 500 into recess 208 forms a fluid-tight seal between ferrule 500 and body 200 .
FIG. 5 is a cross-sectional view of a fitting 900 in an alternate embodiment. Many of the elements of fitting 900 are similar to those of fitting 100 , and bear the same reference numeral. Fitting 900 varies in that the adapter sealing surface 902 is different than adapter sealing surface 114 . FIG. 6 is an enlarged view showing the adapter sealing surface 902 . Adapter sealing surface 902 has the same angle relative to the longitudinal axis 104 as sealing surface 302 .
As shown in FIG. 6 , the adapter sealing surface includes a cutaway 904 rendering the surface area of the adapter sealing surface 902 less than that of sealing surface 302 . Cutaway 904 includes a first wall 906 substantially parallel to longitudinal axis 104 . As second wall 908 is substantially perpendicular to longitudinal axis 104 . In use, bolts 800 are tightened driving the adapter 100 into body 200 . This compresses metal tubing 700 between the adapter sealing surface 902 and sealing surface 302 as shown in FIG. 6 . As a peak of the metal tubing is compressed, the edge between sealing surface 902 and first wall 906 applies force to the tubing 700 to form an annular crimp 710 in the tubing 700 . This crimp serves as a line seal and accommodates imperfections in the tubing 700 due to weld seams, mechanical tolerances, etc.
The tubing containment system may be used in a number of applications including direct underground burial, above ground outdoor use, indoor use at elevated pressure for safety and other secondary containment and sensing systems for petrochemical lines.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation. | A fitting for use with metal tubing in a jacket, the fitting including: an adapter, the adapter having a tubular member defining a longitudinal passage having a longitudinal axis for fluid flow; a body for receiving the tubing, the body positioned opposite the adapter and aligned with the longitudinal axis; a sealing member positioned between the adapter and the body; a retainer positioned external to the sealing member, the retainer receiving the adapter and receiving the body; a first flange located near the adapter and a second flange located near the body; and a fastener for drawing the first flange and second flange towards each other. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a water resistant sunscreen and insect repellent on a disposable applicator. More particularly, the present invention relates to a single-use disposable towel or wipe made from a non-woven, woven or porous material saturated with a combination water resistant sunscreen and insect repellent composition. The water resistant sunscreen and insect repellant composition, when rubbed over the skin, provides a thin, non-greasy film that provides protection against insect bites as well as the harmful effects of the sun.
It is well known that sunlight contains ultraviolet A and ultraviolet B rays (UVA and UVB rays). Prolonged exposure to the sun's ultraviolet rays can be extremely harmful to unprotected skin, and in some cases can lead to a person developing early wrinkles, skin cancer and other skin related problems. Sunscreens and sunblocks have been developed to reduce the harmful effects of the sun on the skin—they are generally contained in lotions which vary on a scale of increasing protection from 1 to 50 (although there are questions regarding the effectiveness of products claiming protection factors above about 30). The scale is called the Sun Protection Factor (“SPF”). The SPF value of a sunscreen allows the consumer to determine the degree of sunburn protection that the user desires for a given period of time from direct exposure to the sun's ultraviolet rays.
Another well known problem that arises from spending time outdoors is exposure to insects and insect bites. Mosquitoes, flies and ticks can be annoying and can cause painful bites which have the potential to spawn secondary infections or transmit diseases such as West Nile virus, Lyme disease, spotted fever and numerous other serious illnesses. Insect repellents are often used to discourage biting insects from landing on treated skin or clothing.
Combination sunscreen-insect repellents are well known compositions for protecting the skin against both insect bites and the harmful effects of prolonged exposure to the sun. Generally, they are commercially available in the form of aerosols, pump sprays or lotions that have a limited effectiveness and other considerable draw-backs. Primarily, combination sunscreen and repellant compositions can be greasy, have a foul odor and are only effective for short periods of time. These compositions typically require multiple applications and are easily removed in water. This is a distinctive problem in warm or humid climates or when a person is engaged in an activity which causes them to perspire.
In addition, aerosols, pump sprays and lotions can be somewhat difficult to apply. They are not easily controlled, especially around irregular surfaces such as the face. This can result in the unintentional inhalation of mist or vapors, or possibly cause excess chemical to come in contact and irritate the user's eyes. Furthermore, because of the high viscosity, lotions are sometimes ineffective in permitting the sunscreen-repellent composition from absorbing into skin surfaces that are partially covered by hair, such as the legs or chest. Lotion, even after being massaged into such areas after application, tends to intermingle with the hair. Instead of being absorbed into the skin, the lotion will merely congeal on top of the surface—providing less protection for the user.
Furthermore, existing aerosols, pump sprays and lotions containing both sunscreen and insect repellent agents are inconvenient and bulky. They are relatively heavy and require a large storage area for transporting. In addition, the applicators, e.g., pump and spray bottles often break before the compositions are used up, thus wasting product.
Accordingly, there exists a need for a combination sunscreen and insect repellent that is long lasting and effective, but fast, easy and safe to apply. Desirably, such a combination sunscreen and insect repellant provides a single use, one-step controlled application that is water resistant, non-greasy, pleasant smelling and cost effective. More desirably, such a composition has reasonable manufacturing and packaging costs, and uses industry standard effective and long lasting materials.
BRIEF SUMMARY OF THE INVENTION
A disposable personal applicator is formed from a non-woven, woven or porous fibrous material that is saturated with a composition containing a waterproof sunscreen and insect repellent. A preferred composition includes a sunscreen agent, an insect repellent agent, a solvent and a film forming agent present in an amount effective to form a thin film when the composition is applied to the skin of a person.
The sunscreen agent is present in an amount effective to provide a SPF from about 5 to 50. Preferably, the sunscreen agent is present in an amount effective to provide a SPF from about 15 to 30.
One suitable sunscreen agent is a composition of homosalate at a concentration of about 2.0 percent to about 15.0 percent by weight of the total composition, octinoxate at a concentration of about 7.5 percent by weight of the total composition, octisalate at a concentration of about 4.0 percent to about 5.0 percent by weight of the total composition and oxybenzone at a concentration of about 5.0 percent to about 6.0 percent by weight of the total composition. The sunscreen can include inactive ingredients, such as acrylates, octylacrylamide copolymer or an alcohol such as ethanol.
A preferred insect repellent agent is DEET present in a concentration of about 5.0 to about 35.0 weight percent of the weight percent of the total composition. A suitable delivery agent is an alcohol based agent, such as ethanol.
The applicator towel is a non-woven, woven or porous fibrous material. The material can be a polymeric fiber, a natural fiber, or a blend of polymeric and natural fibers. Suitable polymeric non-woven, woven or porous fibers are polyethylene fibers, polypropylene fibers or a blend thereof. The non-woven, woven or porous fibrous material can also be formed as a biodegradable material.
These and other features and advantages of the present invention will be apparent from the following detailed description, in conjunction with the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
While the present invention is susceptible of embodiment in various forms, there is hereinafter described a presently preferred embodiment with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiment illustrated.
It should be further understood that the title of this section of this specification, namely, “Detailed Description Of The Invention”, relates to a requirement of the United States Patent Office, and does not imply, nor should be inferred to limit the subject matter disclosed herein.
The present invention provides a single use disposable personal applicator is formed as a towel or wipe made of a non-woven, woven or porous fibrous material that is saturated with a composition containing a waterproof sunscreen and insect repellent. When rubbed over a user's skin, the towel releases a thin, non-greasy film containing the combination sunscreen-repellent composition that provides the wearer with protection against insect bites as well as the harmful effects of prolonged exposure to the sun.
A preferred form of the sunscreen-repellent composition contains a sun a sunscreen agent, an insect repellent agent, a solvent and a film forming agent which is present in an amount effective to form a thin film when the composition is applied to the skin of a user. The composition is saturated in a wipe, preferably a non-woven, woven or porous wipe, which is used to apply the composition to the skin. Once the wipe is rubbed over the skin, sunscreen-repellent composition is released from the wipe and absorbed into the surface of the skin.
It is anticipated that a variety of sunscreen active agents can be used in the present towel composition. For example, sunscreen active agents such as aminobenzoic acid up to about 15.0 percent by weight, avobenzone up to about 3.0 percent by weight, cinoxate up to about 3.0 percent by weight, dioxybenzone up to about 3.0 percent by weight, methyl anthranilate up to about 5.0 percent by weight, octocrylene up to about 10.0 percent by weight, pandimate O up to about 8.0 percent by weight, phenyl benzimidazone sulfonic acid up to about 4.0 percent by weight, sulisobenzone up to about 10.0 percent by weight, titanium dioxide up to about 25.0 percent by weight, trolamine salicylate up to about 12.0 percent by weight and zinc oxide up to about 25.0 percent by weight are anticipated to be suitable for the present towel composition.
A present applicator is a towel article having a sunscreen active agent composition of homosalate at a concentration of about 2.0 percent to about 15.0 percent by weight, octinoxate at a concentration of about 7.5 percent by weight, octisalate at a concentration of about 4.0 percent to about 5.0 percent by weight and oxybenzone at a concentration of about 5.0 percent to about 6.0 percent by weight. The inactive ingredients in the sunscreen can include, for example, acrylates, octylacrylamide copolymer, alcohol (such as ethanol) and, if desired, a fragrance.
The resulting sunscreen has a long efficacy period when subjected to perspiration, underwater submersion or extreme environmental conditions having high humidity. Moreover, the sunscreen agent is present in the composition in an amount effective to provide a SPF of between about 5 and 50, and preferably about 15 to 30.
A suitable insect repellent is M-toluamide, N,N-diethyl, commonly known as DEET, in an amount of about 2.0 percent to about 99.0 percent, and preferably, about 5.0 weight percent to about 35.0 weight percent. DEET is known in the art and is the active ingredient in many commercially available insect repellent products. It has been shown to be safe for direct application to human skin, and is effective in repelling biting insects such as mosquitoes, flies and ticks which may carry infectious diseases. The resulting composition containing the repellent agent has a pleasant odor, and is applied in such a manner that minimizes concerns regarding inhaling or ingesting mists or vapors. Since the DEET is combined with the sunscreen agent, the repellent agent is highly resistant to water, yet can be easily removed by scrubbing with soap and water. The composition was tested under strict laboratory conditions using appropriate protocols approved by the FDA and EPA.
One solvent for use in the present formulation of the water resistant sunscreen and insect repellent composition is an alcohol such as ethanol. The solvent is present in a concentration of about 2.0 to about 80.0 percent by weight of the composition, and preferably is present in a concentration of about 60.0 percent of the composition. Suitable film forming agents are DEET and sunscreen mixtures. The film forming agent serves to protect, and is present in a concentration of about 2.0 to about 80.0 percent by weight of the composition, and preferably is present in a concentration of about 40.0 percent of the composition.
The towel or wipe applicator of the present invention is a non-woven, woven or porous fibrous material which has a high wet strength and provides a pleasant feel when rubbed over the skin. It is sufficiently bulky and strong to prevent break up during use, but not too substantive to make the user reluctant to dispose of the article after single use. The fibrous material can be made from either a natural or polymeric fiber, and has a basis weight of about 15 to 90 grams per square meter (gsm). Suitable polymeric materials for forming the fibers of the non-woven, woven or porous towel or wipe are polyethylene and polypropylene. It is anticipated that other synthetic materials and natural materials having similar characteristics and weight would be equally suitable for use in the current invention, which other synthetic and natural materials are within the scope and spirit of the present invention. It is also anticipated that a readily biodegradable or dispersible material can be used for the towel to reduce environmental concerns regarding disposal or the like.
The towel or wipe applicator is evenly saturated with the sunscreen-repellent composition in such a manner that the composition is released when the wipe is rubbed over the user's skin. One embodiment of the towel has the wiper (dry towel) saturated with a composition of about 1.0 to about 45.0 percent by weight of sunscreen, about 1.0 to about 45.0 percent by weight of insect repellent, about 2.0 to about 80.0 percent by weight of solvent and about 1.0 to about 80.0 percent by weight of film forming agent. A preferred towel includes the sunscreen agent mixtures in a concentration of about 38.0 percent, the alcohol solvent (e.g., ethanol) in a concentration of about 47.0 percent, and the film forming agent DEET and sunscreen mixtures in a concentration of about 31.0 percent. A present applicator includes a towel that is about 22.4 percent by weight of the applicator in total (total towel and composition), DEET that is about 15.5 percent by weight of the applicator in total; sunscreen that is about 15.5 percent by weight of the applicator in total and alcohol (e.g., ethanol) that is about 46.5 percent by weight of the applicator in total.
All patents referred to herein, are hereby incorporated herein by reference, whether or not specifically done so within the text of this disclosure.
In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular.
From the foregoing it will be observed that numerous modifications and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present invention. It is to be understood that no limitation with respect to the specific embodiments disclosed is intended or should be inferred. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims. | A single-use disposable applicator for applying sunscreen and insect repellent to the skin is a non-woven, woven or porous fibrous material wipe that is saturated with a composition containing a waterproof sunscreen agent and an insect repellent. A film forming agent and solvent may also be present. When rubbed over the skin, the wipe provides a thin, non-greasy film that provides protection against UV absorption and insect repellent properties. The sunscreen and insect repellent combination contained in the wipe has an SPF factor between 2 and 50 and is long lasting and water resistant, which makes it ideal for use during hot or humid weather conditions. | 0 |
TECHNICAL FIELD
[0001] The invention pertains to a device to support cardiac function. In particular, the device according to the invention serves to support a pumping function of a heart.
BACKGROUND
[0002] Due to illness, the pumping function of a heart can be reduced, which is also called cardiac insufficiency. Cardiac insufficiency is from the medical as well as from the economical standpoint of great and increasing importance. In the second decade of this century, 23 million people worldwide will suffer from cardiac insufficiency; the annual rate of new cases will be about 2 million people. In the US alone, 5 million people are currently suffering from cardiac insufficiency. Here, the annual rate of new cases is approximately 550,000 people. Already in this decade, the number of incidences in people over 50 years of age will double to more than 10 million. The same applies to the European continent.
[0003] Causes for cardiac insufficiency can be impaired contractility or reduced filling of the cardiac chambers due to damage to the myocardium. Hypertension can lead to an increased pumping resistance, which can also negatively affect the pumping function of the heart. The pumping function of a heart can also be reduced by leaking valves (e.g., a leaking aortic valve or mitral valve). Impairments of the cardiac conduction system generate arrhythmias, which can also lead to a reduced pumping function of the heart. If the movement of the heart is restricted from the outside, e.g., due to an accumulation of fluid in the pericardium, this can result in a reduced pumping function as well. Cardiac insufficiency often leads to shortness of breath (especially in the case of left ventricular insufficiency), or to water retention in the lungs or in the abdomen (in particular in the case of right ventricular insufficiency).
[0004] Different types of cardiac insufficiencies are treatable with medication or surgery. In some cases of arrhythmias, normal cardiac rhythm can be restored with a pacemaker. A leaking valve can be replaced surgically with a cardiac valvular prosthesis. A reduced pumping function can be assisted by an implanted heart pump. A treatment approach addressing the various causes of heart insufficiency is to assist the pumping function of the heart by means of an implant, which exerts mechanical pressure onto the heart and therefore improves its pumping performance.
[0005] Some known mechanical ventricular assist devices have been disclosed in U.S. Pat. No. 5,749,839 B1 and U.S. Pat. No. 6,626,821 B1, and in WO application 00/25842. These documents disclose mechanical ventricular assist devices that require open-chest surgery. Many cardiac assist systems are complex and can only be implanted by means of an elaborate surgical procedure. All cardiac assist systems are integrated into the blood circulation of the patients. Improved centrifugal or magnetically supported impeller systems carry blood continuously. The contact of the blood with the surface of the implanted systems poses a great engineering and medical challenge. Common complications of cardiac assist systems are strokes, hemorrhage and septicemia. They often lead to long-term hospitalization and frequent re-admissions of patients already released from the hospital.
SUMMARY
[0006] Various aspects of the invention feature a heart support system having a constraint sized to fit about at least a portion of an adult human heart in a living body, an expandable chamber disposed within the constraint so as to apply pressure against the heart when expanded, and a connector system including a pneumatic connection port in hydraulic communication with the expandable chamber.
[0007] In several examples the system includes a sheath configured to transition from a non-expanded state into an expanded state, with the sheath being self-expanding and being configured to be inserted into a delivery system, and which in the expanded state can at least partially enclose a heart. One potential advantage of the device is that it may be implanted using minimally invasive procedures.
[0008] In some implementations, the sheath can be made of a wire mesh, which can have diamond-shaped cells. Preferably, the mesh is made of a shape memory alloy. The crossing points of the wires of the wire mesh can be permanently attached to each other, thus increasing the stability of the sheath. The crossing points may also be separable, which increases the flexibility of the sheath and thereby can make the sheath easier to compress. Or some of the crossing points may be permanently interconnected while other crossing points are not permanently interconnected. By selecting suitable crossing points to be permanently interconnected, and crossing points that are not permanently interconnected, the stability and flexibility of the sheath can be adjusted.
[0009] According to one aspect of the invention, the sheath can also consist of a lattice structure, with the lattice structure consisting of links, and multiple links defining one cell. The lattice structure exhibits a diamond-shaped lattice structure. The links and the intersections of the links exhibit enforcements in order to increase the stability of the sheath. The effect of the enforcements is similar to the effect of the interconnected crossing points in embodiments of the sheath in the form of a wire mesh. The links and the intersections can also be made of a thinner or weaker material in order to increase the flexibility of the sheath. The effect of a thinner or weaker material at intersections is similar to the effect of the non-interconnected intersections in embodiments of the sheath in the form of a wire mesh.
[0010] The sheath can also be made of a solid material, from which parts have been removed. For example, the sheath can be made of a tube or an individually shaped sheath sleeve, into which holes have been formed or cut. The holes can be formed such that the sheath exhibits increased stability in some areas, and increased flexibility in other areas.
[0011] Generally, areas of increased stability are desired in situations, in which the sheath acts as an abutment. Areas of greater flexibility can enable the natural motion of the heart. Increased flexibility is also advantageous for compressing the sheath into a delivery system.
[0012] The sheath generally exhibits openings being created by the wires of the wire mesh, the links of the lattice structure, or by the holes formed in the sheath sleeve. The openings can be rectangular, diamond-shaped or round. The cells or holes can have a pin opening of 1 mm to 50 mm. A pin opening is defined as the largest diameter of a pin, which can be pushed through a cell or a hole. Using the holes, the stability and flexibility of the sheath can be adjusted individually. The holes also allow the exchange of substances from the inside of the sheath with the outer environment of the sheath.
[0013] The sheath can be covered with a membrane; the membrane may, in particular, be made of polyurethane, silicon or polytetrafluorethylene (PTFE). The membrane can reduce the mechanical stress exerted by the sheath onto the pericardium or the myocardium. The membrane can also increase the biocompatibility of the sheath. A coating of the membrane with an active substance is also conceivable.
[0014] Another aspect of the present invention features a method of manufacturing a cardiac assist device. The method includes using a virtual or real image of a heart and forming a sheath based on the shape of the heart image.
[0015] The method can be used to manufacture a custom-made sheath. The shape of the sheath can match the form of the 3D-image of the surface of the heart, spatially stretched by a factor. In particular, the stretch factor can range from 1.01 to 1.2. A sheath applied to a true-to-scale real or virtual 3D image of the heart should exhibit a distance to the 3D image of 1 to 10 mm, in particular 2 to 8 mm, in particular 3 to 5 mm.
[0016] Additional features and advantages of the invention will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
[0017] FIG. 1 shows a human torso with an implanted device and an extracorporeal supply unit.
[0018] FIG. 2 shows a human torso with an implanted device and a partially implanted supply unit.
[0019] FIG. 3 shows a human heart with the device.
[0020] FIGS. 4 a and 4 b show a cross-section through the heart with the device along line A-A in FIG. 3 .
[0021] FIG. 5 shows a step of the implantation of the device.
[0022] FIG. 6 shows a step of the implantation, in which a pericardium seal has not yet been screwed shut.
[0023] FIG. 7 shows a step of the implantation, in which a pericardium seal is screwed shut.
[0024] FIG. 8 shows a partially expanded sheath with a sleeve.
[0025] FIGS. 9 a - c show different views of a closed pericardium seal.
[0026] FIG. 10 shows a tool for the closing of a pericardium seal.
[0027] FIG. 11 shows a plug connector system of the device.
[0028] FIG. 12 a shows a heart with anatomical points of reference.
[0029] FIG. 12 b shows a cross-section of the heart from FIG. 12 a.
[0030] FIG. 13 a shows a 3D view of part of a heart with a system of coordinates.
[0031] FIG. 13 b shows a 2D-rollout of the 3D view from FIG. 13 a with a system of coordinates.
[0032] FIG. 14 a shows a 3D view of a sleeve with augmentation and positioning units.
[0033] FIG. 14 b shows a 2D rollout of a sleeve with augmentation and positioning units from FIG. 14 a.
[0034] FIGS. 15 a - b show one compressed and one expanded augmentation unit in the form of a chamber with a bellows-type section.
[0035] FIG. 16 a shows a 3D view of a sleeve with sensors and/or electrodes.
[0036] FIG. 16 b shows a 2D rollout of the sleeve with sensors and/or electrodes from FIG. 16 a.
[0037] FIG. 17 shows a sample embodiment for a sleeve with augmentation and positioning units.
[0038] FIG. 18 shows a sample embodiment for a sleeve with sensors and electrodes.
DETAILED DESCRIPTION
[0039] FIG. 1 shows an embodiment ( 10 ) of a device in the implanted state. In this example, the device is implanted into a human body. The device, however, can also be implanted into an animal body, in particular into the body of a mammal like a dog, a cat, a rodent, a primate, an even-toed ungulates or an odd-toed ungulate. Depending on the species, the form and the mode of operation of the device is adjusted, in order to accommodate anatomical and/or physiological needs of the individual species.
[0040] FIG. 1 shows a human torso with the device. The device includes a sheath ( 2 ), which can at least partially enclose the heart ( 61 ). Multiple components inserted in the sheath ( 2 ) support the cardiac function ( 61 ). The device also includes a supply unit ( 30 ).
[0041] The sheath ( 2 ), which can at least partially enclose the heart ( 61 ), is configured to transition from a non-expanded state into an expanded state. Preferably, the sheath ( 2 ) is self-expanding and can be inserted into a delivery system in the non-expanded state. The sheath ( 2 ) can be a mesh, in particular a wire mesh, whereby the wire mesh can be at least partially made of a shape memory alloy.
[0042] The sheath ( 2 ) at least partially encloses the heart ( 61 ) in the implanted state and is located inside the pericardium ( 6 ). Embodiments in which the sheath ( 2 ) is placed outside of the pericardium ( 6 ) are possible as well. These embodiments are not described separately; rather, the description for embodiments for implantation inside and outside the pericardium ( 6 ) (with the exception of the not-required pericardial seal ( 5 ) in embodiments of the sheath ( 2 ) for implantation outside the pericardium ( 6 )) is applicable. The architecture of the sheath ( 2 ) is explained in greater detail in a later section of the description.
[0043] Located inside the expandable sheath ( 2 ) is at least one expandable unit, which can be used to apply pressure to the heart ( 61 ). The expandable unit can be a mechanical unit, configured to transition between an expanded and a non-expanded state. Such a mechanical unit can include spring elements, which can be tensioned and released, or lever elements, which can be folded and unfolded. Preferably, the expandable units are chambers, which can be filled with a fluid. Suitable fluids for the filling of a chamber include liquids, gases, or solids (like nanoparticle mixtures, for example), or mixtures of fluids and/or gases and/or solids. The expandable unit can be secured inside the sheath ( 2 ). Preferably, the expandable unit is attached to a sleeve, which can be inserted into the sheath ( 2 ). The at least one expandable unit is described in greater detail with reference to FIG. 8 .
[0044] The sheath ( 2 ) can furthermore include at least one sensor and/or one electrode, which can be used to detect at least one parameter of the heart ( 61 ). The sensor can be configured to determine the heart rate, the ventricular pressure, the contact force between the heart wall and the expandable unit, the systolic blood pressure, the diastolic blood pressure, the pressure applied to a surface of the heart, the fluid presence, the acidity, the electrical resistance, the osmolarity, the oxygen saturation or the flow through a vessel. The sensor can also be configured to measure the pressure applied by an expandable unit onto a surface, the pH-value, the electrical resistance, the osmolarity of a solution, the oxygen saturation of tissue or blood or the flow through a vessel. The sensor can be attached inside or on the sheath ( 2 ). Preferably, the sensor is secured on a sleeve configured to be inserted into the sheath ( 2 ). In addition to the at least one sensor or in place of the sensor, the sheath ( 2 ) can also include at least one electrode configured to measure a parameter, like e.g. the action potential at the myocardium during the excitation process, or to stimulate a tissue with currents. The sensor can also be an electrode. The sensor and the electrode are explained in greater detail in a later section of the description.
[0045] FIG. 1 shows a supply unit ( 30 ), which can be worn outside the body. The supply unit can also be partially or completely implanted into the body, which will be explained in the following sections in greater detail. If the supply unit ( 30 ) is worn outside the body, it may be attached to a chest belt, to a hip belt, or to an abdominal belt. The supply unit ( 30 ) is equipped with an energy storage device allowing the expandable unit to be powered. The energy storage device can be available in the form of a rechargeable battery providing electrical energy to expand the expandable unit. The rechargeable battery is exchangeable. The supply unit ( 30 ) can also include a pressure storage device supplying a compressed gas, to inflate an inflatable chamber. Suitable gases are, among others, compressed air, CO 2 , or inert gases. The housing of the supply unit ( 30 ) itself can serve as a pressure storage housing. The supply unit ( 30 ) can furthermore contain pumps, valves, sensors and displays. The supply unit ( 30 ) can furthermore include a microprocessor configured to receive and process data from the at least one sensor. If the supply unit ( 30 ) is worn outside the body, the required energy can be transferred by direct connection via a cable ( 4 ) or connectionless via electromagnetic induction, for example. The data from the at least one sensor can also be transmitted directly via a cable ( 4 ) or connectionless via wireless technology like bluetooth, for example.
[0046] The device can furthermore include a cable ( 4 ) connecting the expandable unit and/or the sensor or the electrode to the supply unit ( 30 ). If the supply unit ( 30 ) is connected directly to the expandable unit and/or to the sensor, or the electrode, a cable ( 4 ) is not required. If the expandable unit is a mechanical unit which, using electrical energy, is configured to transition from a non-expanded state into an expanded state, or from an expanded state into a non-expanded state, the cable ( 4 ) includes lines configured to transfer the required energy from the supply unit ( 30 ) to the expandable unit. The sleeve can include internal chambers, configured to enable hydraulic alteration of the volume of at least one of the internal chambers of the sleeve. If the expandable unit is a chamber that can be filled by means of a fluid, the cable ( 4 ) includes at least one line allowing the flow of fluid from the supply unit ( 30 ) into the chamber. In some implementations, the cable ( 4 ) includes at least one pneumatic or hydraulic line. If the device includes one sensor or one electrode at, in or on the sheath, then the line leading to the sensor or the electrode can also be in the cable ( 4 ). Embodiments can also exhibit separate cables for providing energy for the expandable unit and for the sensor, or the electrode.
[0047] The cable ( 4 ) connecting the supply unit ( 30 ) to the expandable unit and/or the sensor, or the electrode, can be a single continuous cable or a multi-part cable. In the case of a continuous cable connection, the cable ( 4 ) can be attached to the expandable unit and/or the sensor or one electrode. A connector ( 90 ) can be attached to the end of the cable ( 4 ). The connector ( 90 ) can be connected to the supply unit ( 30 ) via the matching connector ( 91 ). Alternatively, a cable with a connector is only attached to the supply unit ( 30 ). In this case, the matching connector is installed on the sheath ( 2 ), on the expandable unit and/or on the sensor or electrode. In case of a multi-part cable, a cable ( 4 ) with a connector ( 91 ) can be attached to the expandable unit and/or at the sensor or the electrode, and a cable can also be attached to the supply unit ( 30 ), at the end of which can be a connector. The cable ( 4 ) and the connector ( 90 ) are described in greater detail in a later section of the description.
[0048] FIG. 2 shows an embodiment ( 11 ) of the device in the implanted state, where the supply unit ( 31 ) is implanted into the body. Preferred locations for the implantation of the supply unit ( 31 ) are the chest (thoracic) cavity and the abdominal (peritoneal) cavity, which are separated from each other by the diaphragm ( 63 ).
[0049] The sheath ( 2 ) shown in FIG. 2 , the pericardium seal ( 5 ), and the cable ( 4 ) of the device are essentially identical to the components shown in FIG. 1 . The supply unit ( 31 ) can include an energy storage device, which can be used to power the expandable unit located inside the sheath ( 2 ). The energy storage device can be provided in the form of a rechargeable battery, which supplies electrical energy in order to expand the expandable unit. The supply unit ( 31 ) can furthermore contain sensors and one or more microprocessors. If the expandable unit includes at least one chamber, which can be filled with a fluid, then the supply unit ( 31 ) can include pumps, valves, and a pressure reservoir. The pressure reservoir can provide a compressed gas in order to inflate an inflatable chamber. Suitable gases are, among others, compressed air, CO2, or inert gases. The housing of the supply unit ( 31 ) itself can represent the housing of the pressure reservoir. A preferred place for the implantation of the supply unit ( 31 ) is inside the right lateral chest cavity above the liver ( 62 ) and above the diaphragm ( 63 ). Alternatively, or in addition to the pressure reservoir ( 32 ) in the supply unit ( 31 ), the pressure reservoir ( 32 ) can be preferably implanted inside the right lateral abdominal cavity below the diaphragm ( 63 ) and above the liver ( 62 ).
[0050] The pressure reservoir ( 32 ) can be connected to the supply unit ( 31 ) with a tube ( 33 ), which penetrates the diaphragm ( 63 ). The opening in the diaphragm required for the tube ( 33 ) to pass through can be sealed with a seal. The seal can be designed similar to the pericardium seal, as previously described. The supply unit can be connected via a cable ( 4 ) directly with the expandable unit and/or the sensor, or the electrode. Alternatively, at the end of the cable ( 4 ) can also be a connector configured to connect via a matching connector to the supply unit ( 31 ) or to the expandable unit and/or to the sensor or the electrode.
[0051] The cable ( 4 ) runs preferably in the chest cavity above the diaphragm ( 63 ). In the case of a multi-part cable, a cable with a connector can be attached to the expandable unit and/or the sensor or one electrode, and a cable with a matching connector can be attached to the supply unit ( 31 ).
[0052] Alternatively or in addition to a rechargeable battery in the supply unit ( 31 ), a rechargeable battery ( 34 ) can be implanted subcutaneously, into the abdominal wall. The energy required in the supply unit ( 31 ) can be transferred, for example, by electromagnetic induction from an extracorporeal controller ( 35 ) transcutaneously to the rechargeable battery ( 34 ) and be transmitted by an electric cable ( 36 ) from the rechargeable battery ( 34 ) to the supply unit ( 31 ). The extra-corporeal controller ( 35 ) can include an exchangeable rechargeable battery and/or a charging device. The extracorporeal controller ( 34 ) can contain, among others, microprocessors and displays, which can be used for system monitoring of the device and for a display of the operating status. The data from the sensor can be transmitted connectionless via a wireless technology like bluetooth, for example, to and between the supply unit ( 31 ) and the controller ( 34 ).
[0053] FIG. 3 shows an example of a human heart ( 61 ), as well as a sheath ( 2 ), a sleeve ( 7 ) with expandable units ( 71 , 72 ), a sleeve ( 80 ) with sensors ( 81 ) and/or electrodes a cable ( 4 ) with a connector ( 90 ), a catheter ( 103 ) of a delivery system, and a pericardium seal ( 5 ) of the device.
[0054] In this embodiment, the sheath ( 2 ) is shown in the form of a wire mesh. Instead of a wire mesh, the sheath ( 2 ) can alternatively be formed as a lattice consisting of links. In this case, the links create a lattice structure with openings. The sheath ( 2 ) can also consist of a continuous material, from which parts have been removed; for example, the sheath ( 2 ) can consist of a tube and an individually shaped sheath sleeve, into which holes have been formed or cut.
[0055] The sheath ( 2 ) represented in FIG. 3 consists of a mesh made of wires. The wires form crossing points (intersections), which can be permanently interconnected. The wires could, for example, be welded together at their crossing points. Connecting the wires at crossing points increases the stability of the sheath ( 2 ). The crossing points can be free from each other, increasing the flexibility of the sheath ( 2 ) and therefore leading to an easier compressibility of the sheath ( 2 ). In some embodiments, the sheath includes wires that do not cross each other, forming longitudinally oriented struts. Increased sheath flexibility is especially helpful if the sheath ( 2 ) is to be inserted into a delivery system with a smaller diameter catheter ( 103 ). Some of the crossing points of the sheath ( 2 ) can also be permanently interconnected and others not. Through appropriate selection of crossing points that are permanently interconnected and crossing points that are separable, the stability and flexibility of the sheath ( 2 ) can be customized. Areas requiring increased stability in the implanted state can be stabilized by connecting the wires at the crossing points. These can be areas serving as bearing surfaces or abutments for expandable units ( 71 , 72 ). Such abutments can be located directly under an expandable unit ( 71 , 72 ) or next to areas with expandable units ( 71 , 72 ). Areas requiring increased flexibility can be areas which during insertion into a delivery system must be compressed more than other areas. Areas requiring increased flexibility can also be areas, in which an increased flexibility supports the natural movement of the heart. If the sheath ( 2 ) is not made of a wire mesh but of a latticework or a sheath sleeve with holes, the stability and/or the flexibility of selected areas of the sheath ( 2 ) can be adjusted as well. In these cases, adjustments can be brought about by choosing the width of the links and/or the thickness of the links, through the choice of the material to be used, through modifications of the material in certain areas through application of energetic radiation, like heat, for example. Preferably, the sheath ( 2 ) exhibits openings being formed by the wires of a wire mesh, the links of a latticework, or the holes in a sheath sleeve. These openings enable compression of the sheath ( 2 ); they allow the exchange of substances from inside the sheath ( 2 ) with areas outside the sheath ( 2 ) and vice versa; they reduce the amount of material being used for the sheath ( 2 ), and they allow an increased flexibility of the sheath ( 2 ). Shapes which are difficult to realize with solid materials are easier to achieve with mesh-type or lattice-type structures. The openings can be rectangular, round or oval. The openings defined by the wires, the links or the holes in a sheath sleeve have a diameter of approximately 1 to 50 mm, preferably 4 mm to 10 mm. The diameter of an opening is defined as pin opening, meaning that the diameter of the opening represents the largest diameter of a cylindrical pin that can pass through an opening (e.g., a cell or a hole).
[0056] The sheath ( 2 ) is preferably made of a material allowing expansion. Preferably, the sheath ( 2 ) is formed from a material selected from the group consisting of nitinol, titanium and titanium alloys, tantalum and tantalum alloys, stainless steel, polyamide (PA), polyurethane (PUR), polyether ether ketone (PEEK), polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyethylene terephthalate (PET), polymer fiber materials, carbon fiber materials, aramide fiber materials, glass fiber materials and combinations thereof. A material suitable for forming a self-expanding sheath ( 2 ) is at least partially made of a shape memory alloy. Examples of shape memory alloys include NiTi (nickel-titanium; nitinol), NiTiCu (nickel-titanium-copper), CuZn (copper-zinc), CuZnAl (copper-zinc-aluminum), CuAlNi (copper-aluminum-nickel), FeNiAl (iron-nickel-aluminum) and FeMnSi (iron-manganese-silicon).
[0057] The sheath ( 2 ) preferably exhibits a form adapted to the individual shape of the patient's heart, or a cup-shaped form. The individual shape of the patient's heart can be reconstructed from CT or MRI image data. The sheath ( 2 ) is open at the top. The upper rim of the sheath ( 2 ) preferably exhibits loops of a wire or straps, which are formed by links. The loops or straps can serve as anchoring points for a sleeve ( 80 ) with at least one sensor ( 81 ) or one electrode, and/or for a sleeve ( 7 ) with at least one expandable unit ( 71 , 72 ). Positioned at the lower end of the cup-shaped sheath is preferably an opening, through which one or multiple leads of the sensor ( 81 ) or of the electrode, and/or of the expandable unit ( 71 , 72 ) can be passed. The shape of the sheath ( 2 ) at least partially represents the anatomical shape of a heart ( 61 ), in particular the lower part of a heart ( 61 ). Details regarding the shape of the sheath ( 2 ) are explained in greater detail in a later section of the description.
[0058] The sheath ( 2 ) can be covered by a membrane ( 21 ), in particular by a membrane ( 21 ) made of polyurethane or silicon. The membrane ( 21 ) is configured to reduce the mechanical stress applied by the sheath ( 2 ) onto the pericardium ( 6 ) or the myocardium ( 61 ). The membrane ( 21 ) can also increase the biocompatibility of the sheath ( 2 ). The membrane ( 21 ) can be attached to the inner surface or to the outer surface of the sheath ( 2 ). The membrane ( 21 ) can also be manufactured by dipping the mesh- or lattice-type sheath ( 2 ) into an elastomer-containing liquid, which subsequently envelops the latticework or the mesh. The membrane ( 21 ) can then stretch across the openings of the mesh or the lattice. A membrane ( 21 ) on the mesh or the lattice can also improve the abutment properties of an expandable unit ( 71 , 72 ). If an expandable unit ( 71 , 72 ) is, for example, an inflatable chamber, then a membrane ( 21 ) across, at or on the mesh or the lattice can prevent parts of the chambers being pressed through the mesh or the lattice while the chamber is expanding. The membrane ( 21 ) can furthermore prevent excessive widening of the sheath ( 2 ), in particular during inflation of an inflatable chamber. A membrane ( 21 ) on a mesh or a lattice can ensure that an expandable unit positioned on the lattice or the mesh expands into a direction from the mesh or lattice towards the inside only. The membrane ( 21 ) does not interfere with the compressibility of the sheath ( 2 ) while being inserted into a delivery system.
[0059] The sheath ( 2 ) and/or the membrane ( 21 ) can also include an active pharmaceutical ingredient, for example, an anti-thrombotic ingredient, an anti-proliferative ingredient, an anti-inflammatory ingredient, an anti-neoplastic ingredient, an anti-mitotic ingredient, an anti-microbial ingredient, a biofilm synthesis inhibitor, an antibiotics ingredient, an antibody, an anti-coagulating ingredient, a cholesterol-lowering ingredient, a beta blocker, or a combination thereof. Preferably, the ingredient is in the form of a coating on the sheath ( 2 ) and/or the membrane ( 21 ). The sheath ( 2 ) and/or the membrane ( 21 ) can also be coated with extra-cellular matrix proteins, in particular fibronectin or collagen. Bio-compatible coating can be advantageous if ingrowth of the sheath ( 2 ) is desired.
[0060] The expandable unit ( 71 , 72 ) is located inside the sheath ( 2 ). FIG. 3 shows a sheath ( 2 ), into which a sleeve ( 7 ) with expandable units ( 71 , 72 ) in the form of inflatable chambers is inserted. The expandable unit ( 71 , 72 ) is being supplied by a line ( 41 ) inside the cable ( 4 ). The expandable unit ( 71 , 72 ) can be a hydraulic or a pneumatic chamber. The expandable unit ( 71 , 72 ) can be attached directly to the sheath ( 2 ) without a sleeve ( 7 ). The expandable unit ( 71 , 72 ) can also be attached to a sleeve ( 7 ), and the sleeve ( 7 ) can be attached inside the sheath ( 2 ). The expandable unit ( 71 , 72 ) can be designed to apply pressure to the heart ( 61 ). The applied pressure can be a permanent pressure, or it can be a periodically recurring pressure. The device can include different types of expandable units ( 71 , 72 ). The device can include at least one augmentation unit ( 71 ). The device can include at least one positioning unit ( 72 ). The augmentation unit ( 71 ) and/or the positioning unit ( 72 ) can be attached directly to the sheath ( 2 ) or onto a sleeve ( 7 ), which is inserted into the sheath ( 2 ).
[0061] An augmentation unit ( 71 ) is a unit that can be periodically expanded and relaxed, and thereby applies a rhythmical pressure to the heart ( 61 ). The pressure is preferably applied in the areas of the heart muscle, under which a ventricle is located. By applying pressure on a ventricle by means of the augmentation unit ( 71 ) the natural pumping motion of the heart ( 61 ) is being amplified or substituted, and the blood inside the heart ( 61 ) is pumped from the ventricle into the discharging artery. A pressure applied by an augmentation unit ( 71 ) to a right ventricle assists the ejection of the blood from the right ventricular chamber into the pulmonary artery. A pressure applied by an augmentation unit ( 71 ) to a left ventricle assists the ejection of the blood from the left ventricular chamber into the aorta. The positioning of the augmentation unit ( 71 ) inside the sheath ( 2 ) is explained in greater detail in a later section of the description.
[0062] A positioning unit is preferably expanded during the operation of the device in support of the heart function more statically than periodically. The positioning unit ( 72 ) can be expanded in order to fix the device to the heart and to ensure proper fitting of the device. A positioning device ( 72 ) can also be used to respond to changes in the myocardium (e.g., shrinking of the myocardium due to lack of fluids or enlargement of the myocardium due to the absorption of fluids). If the size of the myocardium decreases or increases within a particular period of time, a positioning unit can be expanded or relaxed further in order to ensure a perfect fit. The positioning unit ( 72 ) may, for example, also be used to ensure that the device does not lose contact to the heart wall over the span of a heartbeat. Loss of contact can lead to impact stress between the myocardium and the device, and/or cause malfunction of the sensors ( 81 ) and/or electrodes. In some implementations, the positioning unit ( 72 ) can counteract the pathological, progressive expansion of the damaged myocardium in heart failure patients. The positioning of the positioning unit ( 72 ) inside the sheath ( 2 ) is explained in greater detail in a later section of the description.
[0063] Located at the lower end of the sheath ( 2 ) can be an opening, through which the lead ( 83 ) from the sensor ( 81 ) or the electrode and/or the line ( 41 ) of the expandable unit ( 71 , 72 ) can be passed. The opening can be installed at the lower distal end of the sheath ( 2 ). Alternatively, the opening can also be installed on one side of the sheath ( 2 ). Shown in FIG. 3 is an opening at the lower distal end of the sheath ( 2 ), through which one cable ( 4 ), which includes all leads ( 41 , 83 ), has been routed. Instead of one cable ( 4 ), there can be multiple separate cables. The cables can be routed through one opening of the sheath ( 2 ) or through multiple openings of the sheath ( 2 ). Attached to the end of the cable ( 4 ) is a connector ( 90 ), which is used to connect the sensor ( 81 ) or the electrode, and/or the expandable unit ( 71 , 72 ) to a supply unit. The sheath ( 2 ) is preferably brought inside the pericardium ( 6 ). The cable ( 4 ) is then passed through the pericardium ( 6 ). The device can include a pericardium seal ( 5 ). The seal can seal the opening of the pericardium, which is required for the cables to pass through. The pericardium ( 6 ) is a connective-tissue-type sac surrounding the heart ( 61 ), and which, due to a narrow lubricant layer, gives the heart ( 61 ) the ability to move freely. As a lubricant, it contains a serous fluid, also called liquor pericardii. In order to prevent this lubricant from escaping from the pericardium ( 6 ) through the cable opening, and to prevent any other fluids or solids (like, for example, cells, proteins, foreign matter, etc.) from entering the pericardium ( 6 ), a pericardium seal ( 5 ) can be installed around the cable ( 4 ). The pericardium seal ( 5 ) seals the opening of the pericardium ( 6 ) to the cable ( 4 ). The pericardium seal ( 5 ) can include a first sealing component with a first sealing lip, and a second sealing component with a second sealing lip. A cable ( 4 ) can be routed through a central lumen of the seal. The first sealing lip and/or the second sealing lip can seal the pericardium opening. Located inside the central lumen can be an additional sealing component, which seals the cable ( 4 ) against the pericardium seal ( 5 ) and, if necessary, fixes it as well. The first and the second sealing component can be combined. Preferably, the first and the second sealing component can be secured with a mechanism. Possible mechanisms to secure the sealing components are screw mechanisms, clamping mechanisms, or a bayonet mechanism. The first sealing component and/or the second sealing component can be expandable, or even self-expanding. The pericardium seal ( 5 ) is explained in greater detail in a later section of the description.
[0064] FIGS. 4 a and 4 b show a cross-section of the heart ( 61 ) and part of the device for the support of the cardiac function ( 61 ) along line A-A in FIG. 3 . Starting from the outside to the inside, the following layers are represented: The sheath ( 2 ) with a membrane ( 21 ), a sleeve ( 7 ) with at least one expandable unit ( 71 , 72 ), a sleeve ( 80 ) with at least one sensor ( 81 ) or one electrode ( 82 ), and a transverse cross-section of the heart ( 60 ). Three augmentation units ( 71 ) and three positioning units ( 72 ) are illustrated as examples. In FIG. 4 a , the expandable units ( 71 , 72 ) have been drawn in the non-expanded state. In FIG. 4 b , the augmentation units ( 71 ) have been drawn in the expanded state. The expandable unit ( 71 , 72 ) is located in an area adjacent to a ventricle. An expansion of the expandable unit ( 71 , 72 ) can reduce the volume of the ventricle and cause blood to be ejected from the ventricular chamber. The sensor ( 81 ) or the electrode ( 82 ) is installed in a particular location, where at least one parameter of the heart ( 61 ) can be measured. An electrode ( 82 ) can be installed in a particular location, where the myocardium can be stimulated. In FIGS. 4 a and 4 b , four sensors ( 81 ) in the sleeve ( 80 ) and three electrodes ( 82 ) at the inside of the sleeve ( 80 ) are illustrated as examples.
[0065] FIG. 5 shows a delivery system ( 100 ), which can be used to implant the device to support the cardiac function. The delivery system ( 100 ) includes a catheter ( 103 ), which has a lumen. Preferably, the catheter ( 103 ) is an elongated, tubular component, into which the device for the support of the cardiac function can be inserted in its compressed state. The cross-section of the catheter ( 103 ) and/or of the lumen can be circular, oval or polygonal. The delivery system ( 100 ) can further include a guide wire ( 101 ) and/or a dilatation component. The dilatation component can be soft cone-shaped tip ( 102 ) with a shaft. The guide wire ( 101 ) can be passed through a puncture of the chest wall ( 65 ) between the ribs ( 64 ) and of the pericardium ( 6 ). The soft, cone-shaped tip ( 102 ) can have at the center a circular, oval or polygonal lumen. The soft, cone-shaped tip ( 102 ) can be pushed over the guide wire ( 101 ) and the puncture can be dilated without injury to the epicardium. The distal section of the catheter ( 103 ) of the delivery system ( 100 ) can be passed through the dilated opening. At the distal end of the catheter ( 103 ), a first sealing component ( 51 , 52 ) of the pericardium seal can be snapped on or otherwise attached. The catheter ( 103 ) may, for example, be pushed onto a cone ( 55 ) located at the end of the first sealing component ( 51 , 52 ). Not shown is another embodiment, where a cone is located at the side of the catheter, onto which the first sealing component can be pushed. The catheter ( 103 ) with the attached first sealing component ( 51 , 52 ) of the pericardium seal can be guided via the shaft of the soft tip ( 102 ) and inserted into the pericardium ( 6 ).
[0066] Alternatively, the catheter ( 103 ) and the first sealing component ( 51 , 52 ) of the pericardium seal can be parts that are not interconnected to each other. In this case, the catheter ( 103 ) is initially inserted into the pericardium ( 6 ), and the first sealing component ( 51 , 52 ) can then be pushed into the pericardium via the catheter or withdrawn from the pericardium ( 6 ) through the lumen of the catheter ( 103 ). The first sealing component ( 51 , 52 ) can be a self-expanding sealing component, and is configured to unfold inside the pericardium ( 6 ). Alternatively, a non-expandable part ( 51 ) of the first sealing component contains a self-expanding sealing lip ( 52 ) or a sealing lip ( 52 ), which is configured to fold down while the first seal component ( 51 , 52 ) is being inserted, and which opens up inside the pericardium ( 6 ). The first sealing component ( 51 , 52 ) can expand into a mushroom or umbrella-like shape.
[0067] A second sealing component ( 53 , 54 ) can be inserted along the catheter ( 103 ) or through the catheter ( 103 ). For example, the second sealing component ( 53 , 54 ) can be moved via the catheter ( 103 ) of the delivery system ( 100 ) to the distal end of the delivery system ( 100 ), and then coupled with the first sealing component ( 51 , 52 ). The second sealing component ( 53 , 54 ) can be expandable or non-expandable. The second sealing component ( 53 , 54 ) can be coupled to the first sealing component ( 51 , 52 ). The second sealing component ( 51 , 52 ) is preferably self-expanding, and can in its expanded form assume the shape of a mushroom or an umbrella. The second sealing component ( 53 , 54 ) can be secured with the first sealing component ( 51 , 52 ). Shown in FIG. 5 is a screw mechanism. Other mechanisms to secure the sealing components ( 51 , 52 , 53 , 54 ) include a clamping mechanism or a bayonet seal. After securing the sealing components ( 51 , 52 , 53 , 54 ), the catheter ( 103 ) of the delivery system ( 100 ) can remain on the cone ( 55 ) of the first sealing component ( 51 ) or remain in the lumen of the sealing component ( 51 , 52 ). After the guide wire ( 101 ) and the shaft of the soft tip ( 102 ) have been pulled out of the catheter, the shell with the sensor or the electrode and/or with the expandable unit can be inserted through the lumen of the catheter ( 103 ). The sheath is preferably self-expanding and at least partially encloses the heart ( 61 ) after expansion. Located at the lower end of the sheath can be a connector or a cable with a connector. The supply unit can be directly attached to the sheath, or be connected to the sheath via a cable. After the sheath has been delivered, the delivery system ( 100 ) can be removed. The delivery system ( 100 ) is detached from the sheath by using a pre-weakened breaking point ( 104 ) of the delivery system ( 100 ) and/or on the catheter ( 103 ). Preferably, there are one or multiple pre-weakened breaking points ( 104 ) along a longitudinal axis of the delivery system ( 100 ). The pre-weakened breaking point ( 104 ) can be represented by a breaking line. When the delivery system ( 100 ) is broken open along a pre-weakened breaking point ( 104 ), the delivery system ( 100 ) can be split, unrolled and removed. The delivery system ( 100 ) can also include grasping components ( 105 ), which can be used to apply a force to the delivery system ( 100 ). Preferably, the grasping components ( 105 ) can be used to apply a force directed sideways from the catheter ( 103 ) onto the delivery system ( 100 ) suitable to break open the pre-weakened breaking point ( 104 ).
[0068] The delivery system ( 100 ) can further include a sensor ( 107 ). The sensor can be a temperature sensor ( 107 ) to measure the temperature within the catheter before and during the implantation of the sheath. The temperature sensor ( 107 ) can include a thermocouple, a crystal oscillator or an infrared camera. Alternatively, the sensor can be a sensor to measure at least one of the temperature, pH-value, osmolarity and oxygen saturation of a fluid within the catheter. The wall of the catheter ( 103 ) can further contain heating elements ( 108 ).
[0069] The heating elements ( 108 ) can be used to heat the catheter ( 103 ) and its content before or during implantation. The delivery system ( 100 ) can contain one, two, three, four or more heating elements ( 108 ). The heating elements ( 108 ) can be arranged along the circumference of the catheter wall ( 103 ) equidistantly or irregularly. The heating elements ( 108 ) can span the whole length of the catheter ( 103 ) or cover the length of the catheter only partially. The heating elements ( 108 ) can be adjacent to the catheter wall ( 103 ) at the inside or the outside or they can be within the catheter wall.
[0070] The heating elements ( 108 ) can include heating filaments, heating coils or heating wires, which produce heat via an electrical current. The heating elements ( 108 ) can further consist of ducts within the catheter wall that are perfused by a tempered fluid. The catheter can be heated by using a perfusion fluid whose temperature is higher than the ambient temperature. The ducts can also be perfused by a fluid whose temperature is lower than the ambient temperature, in this way the ducts are utilized to cool down the catheter and its content to a lower temperature. With a temperature sensor and the heating elements, the temperature within the catheter can be maintained at a specific level between −5° C. and +40° C.
[0071] FIG. 6 shows a step of the implantation of the device. After the first sealing component ( 51 , 52 ) in the pericardium ( 6 ) has assumed the expanded form, the sheath ( 2 ), which is preferably self-expanding, can be passed through the lumen of the catheter ( 103 ) of the delivery system and lumen of the first sealing component ( 51 ). After entering through the pericardium seal, the sheath ( 2 ) with the sensor or the electrode and/or the expandable unit expands inside the pericardium ( 6 ).
[0072] Shown in FIG. 6 is also the second sealing component ( 58 , 59 ) before being coupled with the first sealing component ( 51 , 52 ). In this embodiment, the second sealing component ( 58 , 59 ) is a ring-shaped component ( 58 ), e.g., a nut, on which a sealing disk ( 59 ) can be attached to its distal side. The second sealing component ( 58 , 59 ) can be expandable or non-expandable. The second sealing component ( 58 , 59 ) can be moved on the catheter ( 103 ). In this embodiment, the first sealing component ( 51 , 52 ) the sheath with the sensor or the electrode and/or with the expandable unit can be inserted through the lumen and the second sealing component ( 58 , 59 ) exhibit thread sections, which can be screwed together.
[0073] FIG. 7 shows a step of the implantation of the device. In this embodiment, the first sealing component ( 51 , 52 ) is coupled with the second sealing component ( 53 ). The pericardium ( 6 ) can thereby be sealed. The expandable sheath ( 2 ) is partially located inside the pericardium ( 6 ) and can be expanded. FIG. 7 shows markings ( 22 , 23 , 24 ) applied to the sheath ( 2 ). The device generally contains at least one marking ( 22 , 23 , 24 ), which can facilitate the correct placement of the sheath ( 2 ). The marking ( 22 , 23 , 24 ) can be a visual mark, in particular a color marking. The marking ( 22 , 23 , 24 ) can be a phosphorescent or fluorescent marking, making it easier to see in dark environment. Such environments can be present in the operating room itself, and can also be caused by the casting of shadows. Such environments can also be inside the body of a patient. The marking ( 22 , 23 , 24 ) can be made of a material able to be represented by imaging techniques. Suitable imaging techniques include X-rays, CT-methods, and MRI-methods. For example, the marking ( 22 , 23 , 24 ) can be formed of a more radiopaque material than the material of adjacent regions. The marking ( 22 , 23 , 24 ) can have the form of a point, a circle, an oval, a polygon, or the form of a letter. Other forms can be areas created by the connecting of dots. The form can be, for example, a half-moon or a star. The marking ( 22 , 23 , 24 ) can be applied to the sheath ( 2 ) or applied to a sleeve. The marking can be applied in the form of a line. The line can start at the upper edge of the sheath ( 2 ). The line can run from an upper edge of the sheath ( 2 ) to a point at the lower tip of the sheath ( 2 ). The line can run from the upper edge of the sheath perpendicular to the lower tip of the sheath ( 2 ). The starting point of the line at the upper edge of the sheath ( 2 ) can be located at a place, which in the implanted state is close to an area, or at an area, which is level with the cardiac septum. The marking ( 22 , 23 , 24 ) can be located at crossing points of the mesh or the lattice. If the sheath ( 2 ) includes a sheath sleeve, into which holes were formed, the marking ( 22 , 23 , 24 ) can be worked into the sheath sleeve. For example, a hole can be manufactured with a predefined form, which then serves as marking ( 22 , 23 , 24 ).
[0074] The delivery system and/or the catheter ( 103 ) of the delivery system can include one or multiple markings ( 106 ). A marking ( 106 ) on a delivery system can be formed like a marking on a sheath. The marking ( 106 ) can have the form of a dot or the form of a line. A marking ( 106 ) in the form of a line can be a line, which at least partially describes a circumference of the delivery system. A marking ( 106 ) in the form of a line can be a longitudinal line along an axis of the delivery system. A marking ( 106 ) in the form of line can be a straight line or a meandering line. A marking ( 106 ) in the form of a line can be a line running diagonally on a catheter ( 103 ) of a delivery system. A marking ( 106 ) can facilitate the orientation of the delivery system during implantation. A marking ( 106 ) at or on the delivery system can be in alignment with a line at or on a medical implant. For example, the medical implant can be a device for the support of the cardiac function, which can be compressed. In a compressed state, the device can be inserted into a delivery system. One or multiple markings ( 22 , 23 , 24 ) on or at the device can be aligned with one or multiple markings ( 106 ) on or at the delivery system. Such markings ( 22 , 23 , 24 , 106 ) facilitate the orientation of a medical implant. Markings ( 22 , 23 , 24 ) can also be located along an axis of a medical implant. Such markings ( 22 , 23 , 24 ) can be helpful in tracking the progress of the discharge of a medical implant out of the delivery system. The delivery system and/or a catheter ( 103 ) can be made of a transparent material, which allows the medical implant to be visually traceable during insertion.
[0075] FIG. 8 shows a step of the implantation of the device. In this example, the first sealing component ( 51 , 52 ) and the second sealing component ( 53 ) of the pericardium seal are interconnected. The device for the support of the cardiac function has already been partially discharged from the delivery system. Shown is a self-expanding sheath ( 2 ). In this embodiment, the sheath ( 2 ) is formed from a wire mesh exhibiting loops ( 26 , 28 ) at the upper edge and/or at the lower edge of the sheath ( 2 ). The sheath ( 2 ) can also be formed of a lattice structure and can exhibit links in the form of straps at the upper edge and/or at the lower edge of the sheath ( 2 ). If the sheath ( 2 ) is formed from a sheath sleeve, into which holes have been formed, the upper edge and/or the lower edge of the sheath ( 2 ) can be designed such that at least one strap is located at the upper and/or lower edge of the sheath ( 2 ). The sheath ( 2 ) represented in FIG. 8 includes a sleeve ( 80 ), which is inserted into the sheath ( 2 ). Another sleeve including at least one expandable unit can be located between the sleeve ( 80 ) and the sheath ( 2 ).
[0076] One or both sleeves can be fastened to the loops ( 26 , 28 ) or straps of the sheath ( 2 ). A sleeve can, in particular, be hooked onto the loops ( 26 , 28 ) or the straps of the sheath ( 2 ). In such case, the sleeve ( 80 ) can exhibit at least one pocket ( 27 ), which can be pulled over at least one loop ( 26 , 28 ) or at least one strap. Another embodiment can include a sleeve ( 80 ), which is turned inside out at its upper edge and/or at its lower edge. This inversion can form a pocket ( 27 ) around the entire sleeve ( 80 ) or around a part thereof, which can be hooked into the upper edge and/or the lower edge of the sheath ( 2 ). In FIG. 8 , the sheath ( 2 ) exhibits multiple markings ( 22 , 23 , 24 , 25 ). As previously described, these markings ( 22 , 23 , 24 , 25 ) can assume different forms or positions. In this case, the markings ( 22 , 23 , 24 , 25 ) are attached to the upper edge and the lower tip of the sheath ( 2 ).
[0077] FIGS. 9 a - c show different views of a pericardium seal ( 5 ). The pericardium seal ( 5 ) serves to prevent the loss of pericardium fluid or also as an option to apply artificial pericardium fluid, medications or other therapeutics. The prevention of loss of pericardium fluid also serves to prevent adhesions of the system with the epicardium. The pericardium seal ( 5 ) generally includes a first sealing component ( 51 ) and a second sealing component ( 52 ). The first sealing component ( 51 ) has a central lumen, and the second sealing component ( 53 ) has a central lumen. The first sealing component ( 51 ) can be coupled with the second sealing component ( 53 ). After coupling the first sealing component ( 51 ) to the second sealing component ( 52 ), the pericardium seal ( 5 ) exhibits a lumen running through the pericardium seal ( 5 ). The lumen can be formed exclusively by the central lumen of the first sealing component ( 51 ), or the lumen can be formed exclusively by the central lumen of the second sealing component ( 53 ). In another embodiment, the lumen can also be formed from both lumens of the two coupled sealing components ( 51 , 53 ). Located in the lumen can be a sealing gasket, an O-ring, a labyrinth seal or another sealing component ( 56 ). A sealing component ( 56 ) in the lumen of the pericardium seal can seal the pericardium seal ( 5 ) against an object protruding through the pericardium seal ( 5 ). For example, a cable can be passed through the pericardium seal ( 5 ), which is then sealed against the pericardium seal ( 5 ). A sealing component ( 56 ) in the lumen can serve not only to seal but also to fix an object protruding through the lumen of the pericardium seal. The sealing component ( 56 ) can be attached to both sealing components ( 51 , 53 ) or to one of both sealing components ( 51 , 53 ) only.
[0078] Using a mechanism, the first sealing component ( 51 ) can be secured with the second sealing component ( 53 ). A mechanism to secure a first sealing component ( 51 ) with a second sealing component ( 53 ) can include a screw mechanism or clamping mechanism. A mechanism to secure a first sealing component ( 51 ) with a second sealing component ( 53 ) can also include a bayonet catch. The first sealing component ( 51 ) and the second sealing component ( 53 ) can be made of the same material or made of different materials. Suitable materials for the first sealing component ( 51 ) and/or the second sealing component ( 53 ) include synthetic materials, metals, ceramics or combinations thereof.
[0079] Attached to the first sealing component ( 51 ) can be a first sealing lip ( 52 ). The first sealing lip ( 52 ) can be part of the first sealing component ( 51 ) or can be attached to the first sealing component ( 51 ). Attached to the second sealing component ( 53 ) can be a second sealing lip ( 54 ). The second sealing lip ( 54 ) can be part of the second sealing component ( 53 ) or can be attached to the second sealing component ( 53 ). The first sealing lip ( 52 ) and the second sealing lip ( 54 ) can be formed of the same material or of different materials. One or both sealing lips ( 52 , 54 ) can be part of the respective sealing component ( 51 , 53 ) and can be formed from the same material as the associated sealing component ( 51 , 53 ). The first sealing lip ( 52 ) and/or the second sealing lip ( 54 ) can be formed of a synthetic material (preferably of an elastomer), natural rubber, rubber, silicon, latex or a combination thereof. The first sealing lip ( 52 ) and/or the second sealing lip ( 54 ) can be disk-shaped. The first sealing lip ( 52 ) and/or the second sealing lip ( 54 ) can exhibit a concave or a convex curvature. Curved sealing lips ( 52 , 54 ) can better adapt to anatomic conditions. The pericardium exhibits a convex form in the area of the cardiac apex. With the sealing lips ( 52 , 54 ) exhibiting a curvature in the shape of the anatomically available form, an improved anatomic fit of the pericardium seal ( 5 ) can be achieved.
[0080] Curved sealing lips ( 52 , 54 ) can also be used to achieve better sealing properties. The first sealing lip ( 52 ) and/or the second sealing lip ( 54 ) can have reinforcements. With increasing radial distance from the lumen of the pericardium seal towards the outside, the first sealing lip ( 52 ) and/or the second sealing lip ( 54 ) can exhibit increased flexibility. Increased flexibility at the edges of sealing lip ( 52 , 54 ) can strengthen the sealing properties of the sealing lip ( 52 , 54 ) and can also support the anatomically correct positioning of the sealing lip ( 52 , 54 ). Increased flexibility at the edges of the sealing lip ( 52 , 54 ) can be achieved through the choice of material. Each sealing lip ( 52 , 54 ) can be made of one material or of multiple materials. Reinforcements of a sealing lip ( 52 , 54 ) can be concentric reinforcements or radial reinforcements. Reinforcements can be achieved by means of variable material thicknesses or by introduction of a reinforcing material. The reinforcing material can be the same material as the base material of the sealing lip ( 52 , 54 ), having been converted into a different form of the material. Alternatively, regions, that are not to be reinforced can be weakened by converting the material of the sealing lip ( 52 , 54 ) into a weaker form of the material. A weakening of the material can be induced by exposure to energetic radiation (e.g., heat). Reinforcements of the material can also be achieved by application of material, whereby the applied material can be the same material as the base material of the sealing lip ( 52 , 54 ), or whereby the applied material can be a material different from the base material of the sealing lip ( 52 , 54 ). Suitable materials for the reinforcement of sections of a sealing lip ( 52 , 54 ) are metals, ceramics, rubber, or a combination thereof.
[0081] One of the two sealing components ( 51 , 53 ) can exhibit a coupling mechanism, allowing the coupling of a sealing component ( 51 , 53 ) with the delivery system or a catheter of the delivery system. The coupling mechanism can consist, for example, of a cone ( 55 ) located at the first sealing component ( 51 ), onto which the delivery system or a catheter of a delivery system can be clamped. The clamping effect can be achieved by the diameter of the cone ( 55 ) being larger than the luminal diameter of the delivery system, for example. The coupling mechanism to couple the pericardium seal ( 5 ) to the delivery system can also be available at the second sealing component ( 53 ). The coupling mechanism can also be provided as a separate part in addition to the sealing components ( 51 , 53 ), and can link the delivery system to one of the two sealing components ( 51 , 53 ) of the pericardium seal ( 5 ). Other embodiments of the coupling mechanism may include, among others, a non-conical (e.g., cylindrical) extension on one of the sealing components ( 51 , 53 ), onto which the delivery system can be placed or glued. In some embodiments, the catheter of the delivery system and a sealing component form a single integrated part. In some embodiments, the catheter can after successful insertion and securing of the pericardium seal ( 5 ) be disconnected from the sealing component ( 51 , 53 ) or the pericardium seal ( 5 ) by means of a pre-weakened breaking point.
[0082] One or both sealing components ( 51 , 53 ) can exhibit engaging components ( 57 ). These engaging components ( 57 ) can be used to apply a force to one or both sealing components ( 51 , 53 ) appropriate to couple and/or secure the sealing components ( 51 , 53 ). Engaging components ( 57 ) on one or on both sealing components ( 51 , 53 ) can be holes, indentations or elevations. The engaging components ( 57 ) can be installed around the circumference of the sealing component ( 51 , 53 ) at an equal distance from each other. The circumferential distance between the engaging components ( 57 ) can also vary. FIGS. 9 a - c illustrate six engaging components ( 57 ) equidistantly disposed around the circumference. On the ring-shaped sealing component ( 53 ), the six engaging components ( 57 ) are installed at an angular distance of approximately 60°. In the case of two, three, four, five, six, eight or more evenly distributed engaging components ( 57 ), the angular distance is 180°, 120°, 90°, 72°, 60°, 45° or less, respectively. The engaging components ( 57 ) can also be installed in an unevenly spaced configuration.
[0083] FIG. 10 shows a pericardium seal ( 5 ) and a tool ( 11 ) to secure a pericardium seal ( 5 ). The pericardium seal ( 5 ) shown in FIG. 10 is essentially identical to the seal shown in FIG. 9 . As an example, the tool ( 11 ) is represented as an elongated tubular tool. Located at the distal end of the tool ( 11 ) are components ( 111 ), which can be at least partially engaged with the engaging components ( 57 ) of a sealing component ( 53 ). In the embodiment shown in FIG. 10 , the inside of the tubular tool ( 11 ) exhibits at the distal end six elevations ( 111 ) pointing to the inside, which can engage with the six engaging components ( 57 ) of the sealing component ( 53 ), for example, with six indentations on the sealing component ( 53 ). The tool ( 11 ) essentially exhibits the same number of components ( 11 ), which are complementary to the engaging components ( 57 ) of the sealing component ( 53 ). The tool ( 11 ) shown in FIG. 10 is a tubular tool, consisting of a complete tube. The tubular component of the tool ( 11 ) can also be half a tube, a quarter tube, or a third of a tube. In the extreme case, instead of the tube, only one shaft or multiple shafts can be attached to a distal, ring-shaped tool. A shaft can extend from the ring-shaped tool in longitudinal direction. A shaft can also extend laterally away from a longitudinal axis of the tool. Other embodiments of the tool ( 11 ) (not shown) can be provided in the form of a modified box wrench or a modified open-end wrench.
[0084] FIG. 11 shows a connector system consisting of two connectors ( 90 , 92 ). The device for the support of the cardiac function includes a sheath with at least one sensor or at least one electrode and/or at least one expandable unit, whereby the sensor or electrode and/or the expandable unit are connected to a supply unit. The sensor or the electrode and/or the expandable unit can be directly connected to the supply unit. The sensor or the electrode and/or the expandable unit can be connected to the supply unit via a cable ( 4 ). The sensor or the electrode and/or the expandable unit can be directly linked to the supply unit via the cable ( 4 ), or the sensor or the electrode and/or the expandable unit can be connected to the supply unit. The supply unit can include a connector ( 92 ). The connector ( 92 ) can be attached directly to the supply unit. The connector ( 92 ) can be connected to the supply unit via a cable ( 4 ). The sensor or the electrode and/or the expandable unit can include a cable ( 4 ). At the end of the cable ( 4 ) can be a connector ( 90 ). The connector ( 90 ) at the end of the cable of the sensor or of the expandable unit matches the connector ( 92 ) at the supply unit. The connector ( 90 ) of the sensor or of the electrode and/or the expandable unit can be a male or a female connector. A female connector on the side of the sensor or the electrode and/or the expandable unit can be advantageous, since the female connector in contrast to the male connector does not include any pins ( 951 ) or any other terminals, which can protrude and therefore could break. If an exchange of the supply unit is required, the connector system is disconnected, and a new supply unit is connected to the connector ( 90 ) of the sensor or the electrode and/or the at least expandable unit. The reconnection of the connector ( 90 ) with a supply unit might cause pins ( 951 ) or other terminals to break. If the pins ( 951 ) or terminals are located in a male connector on the side of the sheath with the sensor or the at last one electrode and/or the expandable unit, an exchange of the sheath may be required. A female connector on the side of the sheath with the sensor or the electrode and/or the expandable unit can be advantageous, since the breaking of pins ( 951 ) or other terminals cannot occur at a female connector. The connector system ( 90 , 92 ) usually includes two connectors. The device can consist of a connector system ( 90 , 92 ) for the sensor or the electrode and/or the expandable unit, or of multiple connector systems. If multiple connector systems are used, a connector system for electrical leads and a connector system for hydraulic and/or pneumatic lines can be provided. The connector system ( 90 , 92 ) represented in FIG. 11 is a connector system consisting of connections to supply the sensor or the electrode and the expandable unit. The number of connections depends on how many sensors or electrodes and how many expandable units are being used. In some implementations, the number does not necessarily have to correlate directly with the number of sensors or electrodes and/or the number of expandable units. Split leads/lines on both sides of the connector system ( 90 , 92 ) are possible, and a pneumatic or hydraulic line is configured to supply one, two, three, four, five, six or more fillable chambers. The filling of the multiple chambers by one line does not have to occur simultaneously; it can also occur individually by means of individually controllable valves. Likewise, one electrical lead inside the cable can be used for multiple sensors or electrodes, and switches can individually energize circuits. The connector system ( 90 , 92 ) represented in FIG. 11 includes four hydraulic or pneumatic connection ports ( 93 , 94 ) and one connection for electrical leads ( 95 , 96 ). The connecting port for electrical leads ( 95 , 96 ) shown in FIG. 11 exhibits 16 connecting components in the form of pins ( 951 ) and pin sockets ( 961 ). More or fewer connections for electrical leads ( 95 , 96 ) and/or pneumatic or hydraulic lines ( 93 , 94 ) can exist in one connector system. The pneumatic or hydraulic lines ( 93 , 94 ) can include one, two, three, four, five, six, seven, eight, nine or ten connections.
[0085] The electric leads ( 95 , 96 ) can include one, two, three, four, five, six, seven, eight, nine, ten, twelve, fourteen, sixteen, twenty or more connections. One electrical connector for electric leads ( 95 , 96 ) can have one, two, three, four, five, six, seven, eight, nine, ten, twelve, fourteen, sixteen, twenty or more connecting components in the form of pins ( 951 ) and pin sockets ( 961 ). The number of connecting components in the form of pins ( 951 ) and pin sockets ( 961 ), however, is identical for the respective pair of connections for electricals leads ( 95 , 96 ). Each of the connections ( 93 , 94 , 95 , 96 ) in one or in both of the connectors of the connector systems ( 90 , 92 ) can have its own seal ( 931 , 952 ). The seal ( 931 , 952 ) of the individual connections ( 93 , 94 , 95 , 96 ) can be a sealing tape or a sealing gasket. The connector system ( 90 , 92 ) can in addition or only one seal inside the connector system ( 973 ) or around the connector system. A seal via the connector system can be a sealing tape or a sealing gasket. The connector parts ( 90 , 92 ) can be interconnected in order to create the connector system ( 90 , 92 ). The connector parts ( 90 , 92 ) can have a guide peg ( 972 ) and a guide slot ( 974 ). The guide peg ( 972 ) and the guide slot ( 974 ) can prevent wrong connection of the two connector parts and/or turning the connector parts the wrong way during connection. The connector parts ( 90 , 92 ) can also include two, three, or more guide pegs ( 972 ) and guide slots ( 974 ). In the case of two or more guide pegs ( 972 ) and guide slots ( 974 ), unequal distances between the individual guide pegs ( 972 ) and guide slots ( 974 ) can be used. The interconnected connector parts ( 90 , 92 ) can also be secured with a mechanism ( 971 ). Such mechanism ( 971 ) can be a screwing mechanism or a clamping mechanism or a bayonet catch. A mechanism to secure the interconnected connector system ( 90 , 92 ) can also be a retainer nut, a clamp, a latch or a snap-lock mechanism. Securing the connector system ( 90 , 92 ) is advantageous, since any accidental partial or complete disconnection of the connector system ( 90 , 92 ) can interrupt the supply of the sensor or the at least one electrode and/or the expandable unit.
[0086] FIG. 12 shows a model for the preparation of a system of coordinates. The development of a system of coordinates can facilitate the manufacture of a device for the support of the cardiac function, since the position for the sensor or one electrode and/or the expandable unit and/or the marking can be exactly defined. FIG. 12 a shows a heart ( 61 ) with anatomical points of reference. The example illustrates the heart ( 61 ) with the aortic arch (AO) originating at the left ventricle (LV) (with head arteries, neck arteries, and subclavian arteries (TR, CL, SCL) branching off), and the pulmonary artery (PU) originating at the right ventricle (RV). Also shown are sections of the inferior vena cava (IVC) and the superior vena cava (SVC). The broken line ( 601 ) represents the height of the valve plane. The point ( 604 ) of the cardiac apex is defined by letting a perpendicular ( 603 ) fall from this plane ( 601 ) through the most distal point of the cardiac apex. The device includes a sheath, into which a sleeve with at least one sensor or one electrode and/or a sleeve with at least one expandable unit can be inserted. The dimension of the sheath and/or the sleeve can be designed such that the upper edge of the sleeve ( 602 ) runs parallel to the valve plane with a downward offset in the direction of the cardiac apex at a distance from the valve plane of 1 mm to 30 mm, 3 mm to 20 mm, 5 mm to 10 mm, preferably 5 mm. The upper edge of the sheath is shown by the line ( 602 ) in FIG. 12 a . The lower edge of the sheath ( 605 ) and/or the sleeve can be parallel to the valve plane with a distance to the most distal point ( 604 ) of 1 mm to 30 mm, 3 mm to 20 mm, 5 mm to 10 mm, preferably 5 mm. FIG. 12 b shows a cutting plane B-B along the line ( 602 ) shown in FIG. 12 a , i.e., along the line corresponding to the upper edge of the sheath.
[0087] FIG. 12 b shows the right ventricular chamber (RV) and the left ventricular chamber (LV), the heart wall and the septal wall separating the cardiac chambers. The points ( 608 ) and ( 609 ) are defined as the points of intersection of the centerlines of the heart wall with the septal wall. The point ( 608 ) is also called the anterior intersecting point of the centerlines of the heart wall with the septal wall. The point ( 609 ) is also called the posterior intersecting point of the centerlines of the heart wall with the septal wall. The center point on a line connecting points ( 608 ) and ( 609 ) is defined as point ( 607 ). These points can be used to define a system of polar coordinates. The z-axis ( 606 ) of the polar coordinate system is defined as the line connecting the most distal point ( 604 ) to the center point ( 607 ) of the line connecting points ( 608 ) and ( 609 ). The circumferential direction of the coordinate system is suggested by the reference numeral ( 610 ) and defined as angle measure φ, whereby a line radially running from the z-axis ( 606 ) through the anterior point of intersection ( 608 ) is defined as φ=0°.
[0088] FIG. 13 shows a sheath and/or sleeve with the coordinate system described above in conjunction with FIG. 12 . FIG. 13 a shows a 3D-model ( 611 ) of a sheath or sleeve with the z-axis ( 606 ) extending through the most distal point ( 604 ) and the center point ( 607 ) of the line connecting points ( 608 ) with ( 609 ). The points ( 608 ) and ( 609 ) are the anterior and the posterior point of intersection of the center lines of the heart wall with the septal wall, whereby the φ=0° line is drawn through the point ( 608 ). The broken line connecting the points ( 608 ) and ( 609 ) along an outer circumference of the sheath or the sleeve, represents the position of the septal wall of the heart as projected onto the sheath/sleeve. At the upper edge of the sheath or the sleeve, the angle measures starting at φ=0° are shown in 30° increments, whereby—viewed from above—the angles increase counterclockwise. Longitudinal lines ( 613 ) projected onto the sheath/sleeve respectively extend along these angles up to the cardiac apex ( 604 ). The angle measure of φ=360° then again corresponds to the angle measure of φ=0°. Contour lines ( 614 ) are indicated at distances of 15 mm increments. The contour lines ( 614 ) and planes are running perpendicular to the z-axis ( 606 ). The broken-dotted line ( 615 ) constitutes a cutting line, where the 3D shape ( 611 ) can be cut open and rolled out. FIG. 13 b shows a rolled-out sheath or sleeve ( 612 ), which has been cut along the line ( 615 ) in FIG. 13 a and then rolled out. The positions ( 608 , 609 ) and lines ( 613 , 614 , 615 , 616 ) shown in FIG. 13 b represent the same positions and lines that are shown in FIG. 13 a.
[0089] FIG. 14 shows a sleeve ( 7 ) with at least one expandable unit ( 71 , 72 ). The 3D-shape of the sleeve ( 7 ) in FIG. 14 a is comparable to the 3D-model explained in conjunction with FIG. 13 a and shows a coordinate system as described above. The sleeve ( 7 ) can at least partially enclose a heart. The sleeve ( 7 ) can at least partially have the shape of a heart. The sleeve ( 7 ) can have a shape similar to the sheath. The sleeve can be inserted into the sheath. The sleeve can be made of synthetic material, polymer, natural rubber, rubber, latex, silicon or polyurethane.
[0090] In FIG. 14 a , the sleeve ( 7 ) with at least one expandable unit ( 71 , 72 ) is shown as a sleeve ( 7 ) with a multiplicity of chambers. FIG. 14 b shows a 2D-rollout of the 3D-model from FIG. 14 a . The rollout represented in FIG. 14 b is essentially identical to the rollout of a 3D-model explained in conjunction with FIG. 13 b . Unlike in FIG. 13 a , the 3D-model in FIG. 14 a is rotated such that a view from above into the sleeve ( 7 ) is possible. In FIGS. 14 a and 14 b , four expandable units ( 71 , 72 ) are shown as examples, three of which are augmentation units ( 71 ) and one is a positioning unit ( 72 ). The expandable units ( 71 , 72 ) can be structurally similar but can serve different purposes, as described above.
[0091] Generally, an augmentation unit ( 71 ) can be periodically expanded and relaxed in order to be configured to apply pressure to the heart. This pressure is preferably applied in ventricular areas. By applying pressure to a ventricle via the augmentation unit ( 71 ) the natural pumping motion of the heart is supported or substituted, and the blood inside the ventricular chamber is pumped into the corresponding artery. A pressure applied by an augmentation unit ( 71 ) to a right ventricle leads to the blood being ejected from the right ventricle into the pulmonary artery. A pressure applied by an augmentation unit ( 71 ) to a left ventricle leads to the blood being ejected from the left ventricle into the aorta.
[0092] FIG. 14 shows three augmentation units ( 71 ), which are located at the upper edge of the sleeve ( 7 ). In this example, each of the augmentation units ( 71 ) is supplied by its own line ( 41 ).
[0093] In the case of augmentation units ( 71 ) in the form of inflatable chamber, the lines ( 41 ) are preferably pneumatic or hydraulic lines. Other embodiments include one, two, three, four, five, six or more augmentation units ( 71 ), which are supplied by one, two, three, four, five, six or more lines ( 41 ). The line ( 41 ) can be made of synthetic material, polymer, natural rubber, rubber, latex, silicon, or polyurethane. The line ( 41 ) can run above, adjacent to or below the augmentation unit ( 71 ). The line ( 41 ) can preferably run below a positioning unit ( 72 ), so that no pressure points result between the line ( 41 ) and the heart wall. The line ( 41 ) can also run above or adjacent to a positioning unit ( 72 ).
[0094] The augmentation units ( 71 ) A1, A2, and A3 shown in FIG. 14 are located in an area at the upper edge of the sleeve ( 7 ) and are each supplied by their own respective line ( 41 ). The augmentation units ( 71 ) A1 and A2 can—as illustrated in FIG. 14 —be positioned such that they can assist a left ventricle. Augmentation unit ( 71 ) A3 is positioned to assist a right ventricle. The individual augmentation units ( 71 ) A1, A2 and A3 can be expanded individually. Augmentation units ( 71 ) A1 and A2 can assist cardiac function for a heart with left ventricular insufficiency. Augmentation unit ( 71 ) A3 can serve to support a right ventricular insufficiency.
[0095] Augmentation units ( 71 ) A1, A2 and A3 can be used for support of a bilateral heart insufficiency. The augmentation units ( 71 ) can be expanded synchronously or asynchronously. Preferably, the expansion of the augmentation units ( 71 ) can be coordinated such that a natural pumping function of the heart is supported.
[0096] A positioning unit ( 72 ) is a unit, which can also be expanded. Preferably, a positioning unit is expanded during operation of the device for the support of the cardiac function more statically than periodically. The positioning unit ( 72 ) can be expanded in order to fix the device to the heart and to optimize the accuracy of the fit of the device. A positioning unit ( 72 ) can also help to respond to changes of the myocardium. If the size of the myocardium decreases or increases, a positioning unit can be expanded or relaxed further in order to ensure a perfect fit.
[0097] FIG. 14 illustrates a positioning unit ( 72 ), which essentially fills the spaces between the three augmentation units ( 71 ) on the sleeve ( 7 ). The positioning unit ( 72 ) can have a distance from one or multiple augmentation units ( 71 ) of 1 mm, 3 mm, 5 mm, 10 mm, 20 mm, 30 mm, 40 mm or more. The positioning unit ( 72 ) can be supplied by its own line ( 41 ), in the case of a chamber fillable with a fluid, by a pneumatic or hydraulic line. Other embodiments include one, two, three, four, five, six or more positioning units ( 72 ), which are supplied by one, two, three, four, five, six or more pneumatic or hydraulic lines ( 41 ). The line ( 41 ) can consist of a synthetic material, polymer, natural rubber, rubber, latex, silicon or polyurethane. The line ( 41 ) for the supplying of the positioning unit ( 72 ) can run below the positioning unit ( 72 ). The positioning unit ( 72 ), shown in FIG. 14 , fills the spaces between the augmentation units ( 71 ). The depicted positioning unit ( 72 ) has extensions that protrude into the spaces between the augmentation units ( 71 ).
[0098] FIG. 15 shows an expandable unit ( 71 , 72 ) in the form of a chamber ( 710 ). The depicted chamber is a bellows-shaped chamber ( 710 ). A bellows-shaped chamber ( 710 ) has at least one section in the form of bellows. Preferably, chamber 710 is a folding bellows consisting of one, two, three, four, five, six, seven or more folds. An outwardly bent edge ( 711 ) can be defined as a fold. An inwardly bent edge ( 712 ) can be defined as a fold. In some embodiments, the regions of the chamber wall between the folds are less stable than the folds. One, multiple or all bent edges ( 711 , 712 ) can be reinforced. A reinforcement of a bent edge ( 711 , 712 ) is advantageous, since the bent edge ( 711 , 712 ) can be exposed to increased stress due to the expanding and relaxing of the chamber ( 710 ). A reinforcement of one or multiple bent edges ( 711 , 712 ) can reduce or prevent material fatigue along the bent edge ( 711 , 712 ). Reinforcement of a bent edge ( 711 , 712 ) can be achieved through a greater wall thickness of the material at the bent edge ( 711 , 712 ). A bent edge ( 711 , 712 ) can also be reinforced through application of additional material, wherein the applied material can be the same material as the underlying material, or wherein the applied material can be a different material than the underlying material. A chamber ( 710 ) can exhibit a top side ( 713 ), a bottom side and a side surface, whereby the side surface is preferably designed in the shape of a bellows. The top ( 713 ) and/or the bottom side can be oval, circular, elliptical, or polygonal. The top side ( 713 ) can have a different shape than the bottom side.
[0099] A bellows-shaped chamber ( 710 ) can be inserted into a sheath of the type described above. The chamber ( 710 ) can be directly attached or fixed inside the sheath. The chamber ( 710 ) can be attached to structural components of the sheath, like, for example, a wire of a wire mesh, a strap of a latticework, or a structure on a sheath sleeve.
[0100] The chamber ( 710 ) can be attached to crossing points of a mesh or latticework. The sheath can be covered by a membrane, as described above. In these cases, the chamber ( 710 ) can also be attached to the membrane. The membrane can also be a bottom side of the chamber ( 710 ).
[0101] The bellows-shaped chamber ( 710 ) can also be fastened to a sleeve ( 7 ). Multiple bellows-shaped chambers ( 710 ) can be fastened to a sleeve ( 7 ). The sleeve ( 7 ) can at least partially have the shape of a heart. The sleeve ( 7 ) can have a shape similar to that of the sheath. The sleeve ( 7 ) can be inserted into the sheath. The sheath ( 7 ) can be fastened and/or fixed inside the sheath. The sleeve ( 7 ) can, in addition to one or multiple augmentation units like, for example, one or multiple bellows-shaped chambers ( 710 ), also exhibit one or multiple positioning units. The bottom side of the chamber ( 710 ) can be made of the same material as the sleeve ( 7 ). The sleeve ( 7 ) can be part of the chamber ( 710 ). The sleeve ( 7 ) can form the bottom side of the chamber. In those cases, only the lateral surfaces, which can be bellows-shaped, are applied to a sleeve ( 7 ). In addition, a top side ( 713 ) can be attached as well. The top side ( 713 ) can be a sleeve as well. Embodiments consist of two sleeves ( 7 ), whereby the sleeves ( 7 ) create the top side and the bottom side of the chambers, and lateral surfaces are formed between the sleeves. In this case, lateral surfaces can also be formed by joining, in particular by welding or gluing together of the two sleeves. The sleeves ( 7 ) can be joined together, in particular, welded or glued together, such that a chamber is formed. In some embodiments, the sleeves are connected to each other in a common edge region. In some embodiments, the chamber defines a gap of 0.1 mm to 5 mm. The line supplying the chamber can be formed similar to the chamber at least partially by joining the two sleeves ( 7 ), in particular by welding or gluing together of the two sleeves ( 7 ). Located on one of the two sleeves ( 7 ) or on both sleeves ( 7 ) can be one or multiple sensors or one or multiple electrodes.
[0102] The sleeve ( 7 ) with the expandable unit can at the upper edge and/or at the lower edge exhibit at least one pocket. The pocket can be at least partially pulled over a structural shape of a sheath. The pocket can, for example, be at least partially pulled over a loop of a wire mesh or a strap of a latticework.
[0103] The sleeve ( 7 ) with the expandable unit can contain an active agent. The sleeve ( 7 ) may, for example, contain an anti-thrombotic agent, an anti-proliferative agent, an anti-inflammatory agent, an anti-neoplastic agent, an anti-mitotic agent, an anti-microbial agent, a biofilm synthesis inhibitor, an antibiotic agent, an antibody, an anticoagulative agent, a cholesterol-lowering agent, a beta blocker, or a combination thereof. The agent is preferably provided in the form of a coating on the sleeve ( 7 ). The sleeve ( 7 ) can also be coated with extra-cellular matrix proteins, in particular, fibronectin or collagen.
[0104] FIG. 16 shows a sleeve ( 80 ) with at least one sensor ( 81 ) and/or at least one electrode ( 82 ). The 3D-shape of the sleeve ( 80 ) in FIG. 16 a is comparable to the 3D-model described in FIG. 13 a and shows a coordinate system as described above. The sleeve ( 80 ) can at least partially enclose a heart. The sleeve ( 80 ) can at least partially have the shape of a heart. The sleeve ( 80 ) can have a shape similar to that of the sheath. The sleeve ( 80 ) can be inserted into the sheath. The sleeve ( 80 ) can be made of a synthetic material, polymer, natural rubber, rubber, latex, silicon or polyurethane. The sleeve ( 80 ) can exhibit a thickness of 0.1 mm to 1 mm, preferably 0.2 mm to 0.5 mm. The sleeve ( 80 ) with the sensor ( 81 ) and/or the electrode ( 82 ) can be pressed against the myocardium by the sleeve with the expandable units. The sleeve ( 80 ) can be coated, in particular, with a lubricant, which reduces the friction between the myocardium and the sleeve ( 80 ) with the sensor ( 81 ) and/or the electrode ( 82 ). A coating, in particular, a coating with a lubricant can also be provided between the sleeve ( 80 ) with the sensor ( 81 ) and/or the electrode ( 82 ) and the sleeve with the expandable unit. The sensor ( 81 ) and/or the electrode ( 82 ) can be worked, molded or welded into the sleeve ( 80 ) or attached, glued onto or sewn onto the sleeve ( 80 ). The sensor ( 81 ) and/or the electrode ( 82 ) can be equipped with reinforcements configured to prevent bending during the compression of the device.
[0105] In FIG. 16 a , the sleeve ( 80 ) is depicted with at least one sensor ( 81 ) and/or at least one electrode ( 82 ) as a sleeve ( 80 ) with a multiplicity of sensors ( 81 ) and electrodes ( 82 ). FIG. 16 b shows a 2D-rollout of the 3D-model from FIG. 16 a . The rollout depicted in FIG. 16 b essentially matches the rollout of a 3D-model explained in conjunction with FIG. 13 b . Unlike in FIG. 13 a , the 3D-model in FIG. 16 a is rotated to allow a view from above into the sleeve ( 80 ). In FIGS. 16 a and 16 b , eight sensors ( 81 ) or electrodes ( 82 ) are shown as examples. Other embodiments can include one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve or more sensors ( 81 ) and/or electrodes ( 82 ). The sleeve ( 80 ) with the sensor ( 81 ) or at least one electrode ( 82 ) can be a net of sensors ( 81 ) or electrodes ( 82 ). The net of sensors ( 81 ) or electrodes ( 82 ) can at least partially enclose the heart. The sensors ( 81 ) or electrodes ( 82 ) in the net of sensors ( 81 ) or electrodes ( 82 ) can be interconnected. The sleeve ( 80 ) can function as the carrier of the net of sensors ( 81 ) or electrodes ( 82 ). The net of sensors ( 81 ) or electrodes ( 82 ) can also be only partially attached to a sleeve ( 80 ). The net of sensors ( 81 ) or electrodes ( 82 ) can also be inserted without a sleeve ( 80 ) into a sheath as the one described above.
[0106] The sensor ( 81 ) or the electrode ( 82 ) can determine a physical or a chemical property of its environment. The property can be detected qualitatively or quantitatively. The sensor ( 81 ) can be an active sensor or a passive sensor. The sensor ( 81 ) can detect at least one parameter of the heart. The sensor ( 81 ) can be configured to determine the heart rate, the ventricular pressure, the systolic blood pressure, the diastolic blood pressure, pressure applied to a surface of the heart, fluid presence, acidity, electrical resistance, osmolarity, oxygen saturation or flow through a vessel. The sensor ( 81 ) can be configured to measure the pressure applied by an expandable unit onto a surface, the pH-value, the electric resistance, the osmolarity of a solution, or the flow through a vessel. The sensor can also be used as an electrode.
[0107] The electrode ( 82 ) can be configured to electrically stimulate areas of the heart and/or to measure the electrical activity at the epicardium during the excitation process. The electrode ( 82 ) can be configured to stimulate the myocardium with the use of electrical impulses. An electrical stimulation can induce a myocardium to contract. The electrode ( 82 ) can be a pacemaker electrode. The electrode ( 82 ) can be an extra-cardial stimulation electrode. With an electrode ( 82 ), the myocardium can be stimulated before, during or after a support of the pumping function of the heart by a sheath with at least one expandable unit. The expansion of an expandable unit can occur before, during or after stimulation with an electrode ( 82 ). The device for the support of the cardiac function can be operated only with at least one expandable unit or only through stimulation with at least one electrode ( 82 ). Simultaneous operation of the expandable unit and the electrode ( 82 ) can be synchronous or asynchronous. The electrode can also be used a sensor.
[0108] The sensor ( 81 ) or the electrode ( 82 ) can be fastened to the sleeve ( 80 ). The sensor ( 81 ) or the at least one electrode ( 82 ) can be glued, sewed or welded to the sleeve ( 80 ). The sensor ( 81 ) or the electrode ( 82 ) can be attached to the inside of the sleeve ( 80 ), preferably welded in. The sensor ( 81 ) or the electrode ( 82 ) can be connected via a lead ( 84 ) to a supply unit. The data detected by the sensor ( 81 ) or the electrode ( 82 ) can be transmitted connectionless via wireless technology, like bluetooth, for example.
[0109] The contacts of the electrodes or sensors or the entire sleeve can be coated with a substance, which increases or improves conductivity. A graphite coating on the contacts, for example, can increase their conductivity.
Example #1
[0110] FIG. 17 shows an embodiment of a sleeve ( 7 ) with at least one expandable unit ( 71 , 72 ). FIG. 17 depicts a 2D-rollout of a 3D-model described in conjunction with FIG. 13 . The illustrated sheath includes three augmentation units ( 71 ) (A1, A2, A3) and a positioning unit ( 72 ) (P). In some embodiments, the augmentation units A1 and A2 each occupy an area of 28.6 cm 2 on the sleeve. The area occupied by augmentation unit A3 in this example is 34.5 cm 2 . The positioning unit ( 72 ) (P) occupies an area 114.5 cm 2 . Under normal conditions, the nominal expansion of the positioning unit (P) is 5 mm (e.g., the positioning unit is partially expanded and exhibits a thickness of 5 mm). The positioning unit can be a chamber, which can be filled and unfilled with a fluid. The thickness of the positioning unit can therefore be between 1 mm and 10 mm, preferably between 3 mm and 7 mm. By changing the thickness of the positioning unit ( 72 ) (P) an increase or decrease of the size of the heart can be compensated, and the correct fit of the sleeve ( 7 ) and/or the sheath essentially remains guaranteed.
[0111] In this example, the thicknesses of augmentation units A1 and A2 can be expanded by about 1.9 cm in order to build up a pressure onto a ventricle (here, the left ventricle). The effective volume expansion of the augmentation units A1 and A2 in this example is 40 ml. The effective volume expansion of the augmentation unit A3 in this example is 50 ml and leads to an effective expansion of the thickness by 1.45 cm. Every corner of an augmentation unit can be described by the coordinates of the corner points (vertices). The coordinate system has been explained in conjunction with FIG. 13 .
[0112] In this example, augmentation unit A1 extends from vertex 1 (φ=359°; z=100) via vertex 2 (φ=48°; z=85) and vertex 3 (φ=48°; z=40) to vertex 4 (φ=328°; z=56), and, in the implanted state, lies flat against the left ventricle. The connection of vertex 1 to vertex 2 essentially extends parallel to the upper edge of the sleeve ( 7 ) at a distance (d) of about 5 mm. The connection of vertex 2 to vertex 3 essentially extends along the φ=48° line. The connection of vertex 3 to vertex 4 essentially extends parallel to the upper edge of the sleeve ( 7 ) shown in the 3D-model. The connection of vertex 4 to vertex 1 essentially extends along the septal line ( 616 ). The corners of the augmentation unit A1 are rounded and describe a circular arc with a diameter of 4 mm.
[0113] In this example, augmentation unit A2 extends from vertex 1 (φ=116°; z=69) via vertex 2 (φ=182°; z=74) and vertex 3 (φ=212°; z=37) to vertex 4 (φ=116°; z=26) and, in the implanted state, lies flat against the left ventricle. The connection of vertex 1 to vertex 2 essentially extends parallel to the upper edge of the sleeve ( 7 ) at a distance (d) of about 5 mm. The connection of vertex 2 to vertex 3 essentially extends along the septal line ( 616 ). The connection of vertex 3 to vertex 4 essentially extends parallel to the upper edge of the sleeve ( 7 ) shown in the 3D-model.
[0114] The connection of vertex 4 to vertex 1 essentially extends along the φ=116° line. The corners of the augmentation unit A2 are rounded and describe a circular arc with a diameter of 4 mm.
[0115] In this example, the augmentation unit A3 extends from vertex 1 (φ=235°; z=92) via vertex 2 (φ=303°; z=108) and vertex 3 (φ=303°; z=64) to vertex 4 (φ=235°; z=48) and, in the implanted state, lies flat against the right ventricle. The connection of vertex 1 to vertex 2 essentially extends parallel to the upper edge of the sleeve ( 7 ) at a distance (d) of about 5 mm. The connection of vertex 2 to vertex 3 essentially extends along the φ=303° line. The connection of vertex 3 to vertex 4 essentially extends parallel to the upper edge of the sleeve ( 7 ) shown in the 3D-model. The connection of vertex 4 to vertex 1 essentially extends along the φ=235° line. The corners of augmentation unit A3 are rounded and describe a circular arc with a diameter of 4 mm.
[0116] The positioning unit P in the example of FIG. 17 is designed to essentially fill the spaces between the augmentation units ( 71 ) on the sleeve ( 7 ). The positioning unit ( 72 ) can also be described as a positioning unit ( 72 ) with extensions, which fill in the areas of the sleeve ( 7 ) that are not filled by the augmentation units. In this embodiment, the positioning unit P is essentially located at a lateral distance (d) from the augmentation units ( 71 ) and the upper edge of the sleeve ( 7 ) of about 5 mm. The positioning unit ( 72 ) is also located at a distance from the cutting line ( 615 ), which can be advantageous during manufacturing. If the sleeve ( 7 ) with the expandable unit is formed in a two-dimensional state, all augmentation units ( 71 ) and positioning units ( 72 ) can be attached to the sleeve ( 7 ) before the sleeve ( 7 ) is rolled into a three-dimensional form.
[0117] In the example of FIG. 17 , the lines ( 41 ) supplying the expandable units ( 71 , 72 ) are hydraulic or pneumatic lines ( 41 ) extending radially from the lower edge of the sheath to the augmentation units. The line ( 41 ) for the augmentation unit A2 extends along the line φ=15° and ends at the height of z=54. The line ( 41 ) for augmentation unit A2 extends along the line φ=165° and ends at the height of z=31. The line ( 41 ) for augmentation unit A3 extends along the line φ=270° and ends at the height of z=65. The line ( 41 ) for the positioning unit P extends along the line φ=330° and ends at a height of z=25.
Example #2
[0118] FIG. 18 shows an embodiment for a sleeve ( 80 ) with at least one sensor ( 81 ) and/or an electrode ( 82 ). Shown in FIG. 18 is a rollout as described in conjunction with FIG. 13 . The sleeve ( 80 ) of this embodiment includes eight sensors ( 81 ) or electrodes ( 82 ), whereby four of these are pressure sensors (force sensor FS1, FS2, FS3, FS4) ( 81 ), and four are electrocardiogram electrodes (e.g., ECG1, ECG2, ECG3, ECG4) ( 82 ). The sleeve ( 80 ) can be made of a synthetic material, polymer, natural rubber, rubber, latex, silicon or polyurethane. The sleeve ( 80 ) can have a thickness of 0.1 to 1 mm, preferably 0.2 mm to 0.5 mm. The four pressure sensors ( 81 ) can be integrated into the sleeve ( 80 ), for example, molded or welded to the inside surface of the sheath. The pressure sensors ( 81 ) can be equipped with reinforcements, which can prevent bending during the compression of the device. The ECG electrodes ( 82 ) can be attached at the side of sleeve ( 80 ) facing the heart. In the embodiment in FIG. 18 , a system of coordinates is depicted as described in conjunction with FIG. 13 . Using the coordinate system, the positions of the sensors ( 81 ) and electrodes ( 82 ) can be determined as follows: pressure sensor FS1 is located at coordinate (φ=17°; z=71), pressure sensor FS2 is located at coordinate (φ=158°; z=48), pressure sensor FS3 is located at coordinate (φ=268°; z=78), pressure sensor FS4 is located at coordinate (φ=67°; z=61). ECG electrode ECG1 is located at coordinate (φ=76°; z=54), ECG electrode ECG2 is located at coordinate (φ=352°; z=39), ECG electrode ECG3 is located at coordinate (φ=312°; z=93) and ECG electrode ECG4 is located at coordinate (φ=187°; z=18). For smaller or larger hearts, the angular coordinates for the sensors ( 81 ) and/or electrodes ( 82 ) essentially remain the same; while the z-value is scaled by a factor. For example, for smaller hearts, the scaling factor can be between 0.85 and 0.95, and for larger hearts, the scaling factor can be between 1.05 and 1.15. | A heart support system featuring a constraint sized to fit about at least a portion of an adult human heart in a living body, an expandable chamber disposed within the constraint so as to apply pressure against the heart when expanded and a connector system including a pneumatic connection port in hydraulic communication with the expandable chamber. The heart support system can include a supply unit with: a source of pressurized fluid and a pneumatic supply line extending from the pressurized fluid source. The pneumatic supply line is connectable to the pneumatic connection port. | 0 |
[0001] This application claims the benefit of the filing date of U.S. Provisional Application No. 61/046,201 filed Apr. 18, 2008, entitled “Clonidine Formulations in a Biodegradable Polymer Carrier,” and U.S. Provisional Application No. 61/046,213 filed Apr. 18, 2008, entitled “Medical Devices and Methods Including Polymers Having Biologically Active Agents Therein,” both of which are hereby incorporated by reference thereto.
BACKGROUND
[0002] Pain control is of prime importance to anyone treating many different diseases and medical conditions. Proper pain relief imparts significant physiological and psychological benefits to the patient. Not only does effective pain relief mean a smoother more pleasant recovery (e.g., mood, sleep, quality of life, etc.) with earlier discharge from medical/surgical/outpatient facilities, but it may also reduce the probability of the acute pain state progressing to a chronic pain syndrome.
[0003] Pain serves an important biological function. It signals the presence of damage or disease within the body and is often accompanied by inflammation (redness, swelling, and/or burning). There are two types of pain based on temporal classification: acute pain and chronic pain. Acute pain refers to pain experienced when tissue is being damaged or is damaged. Acute pain serves at least two physiologically advantageous purposes. First, it warns of dangerous environmental stimuli (such as hot or sharp objects) by triggering reflexive responses that end contact with the dangerous stimuli. Second, if reflexive responses do not avoid dangerous environmental stimuli effectively, or tissue injury or infection otherwise results, acute pain facilitates recuperative behaviors. For example, acute pain associated with an injury or infection encourages an organism to protect the compromised area from further insult or use while the injury or infection heals. Once the dangerous environmental stimulus is removed, or the injury or infection has resolved, acute pain, having served its physiological purpose, ends. As contrasted to acute pain, in general, chronic pain serves no beneficial purpose. Chronic pain results when pain associated with an injury or infection continues in an area once the injury or infection has resolved. Chronic pain may involve injury and changes to the nervous system which is referred to as neuropathic pain. Chronic pain may also involve persistent activation of physiological or nociceptive pathways if the insult is prolonged such as pain associated with certain types of cancer.
[0004] There are many painful diseases or conditions that require proper pain and/or inflammation control, including but not limited to rheumatoid arthritis, osteoarthritis, spinal disc herniation (i.e., sciatica), carpal/tarsal tunnel syndrome, lower back pain, lower extremity pain, upper extremity pain, cancer, tissue pain and pain associated with injury or repair of cervical, thoracic, and/or lumbar vertebrae or intervertebral discs, rotator cuff, articular joint, TMJ, tendons, ligaments, muscles, spondilothesis, stenosis, discogenic back pain, and joint pain or the like.
[0005] One category of chronic pain is chronic pelvic pain syndromes. Chronic pelvic pain may occur in both men and women of all ages and results from a variety of injuries and disorders. It is a common and debilitating problem that can significantly impair the quality of life of the patient suffering from it. Chronic pelvic pain occurs in the pelvic or lower abdominal region and can last for six months or longer.
[0006] In men, chronic pelvic pain may result from chronic idiopathic prostatitis (also referred to as nonbacterial prostatitis or chronic pelvic pain syndrome), chronic bacterial prostatitis or interstitial cystitis where the symptoms typically include in addition to pelvic pain, urinary urgency and frequency, sexual dysfunction and in most cases patients have a hypertonic pelvic floor muscles upon physical examination. The most common treatment for these disorders involves pharmacologic treatments typically orally administered such as antibiotics, anti-inflammatory agents, alpha blockers, anti-spasmodics, analgesics, and muscle relaxants. Alpha blockers have successfully treated symptoms of prostatitis in some patients, although the improvements have been modest and adverse event rates have been significant. Oral muscle relaxants may help decrease pelvic floor tone but often associated with dose-limiting side effects which limit their usefulness.
[0007] Other types of chronic pelvic pain experienced by men include chronic testicular pain (CTP), post vasectomy pain, genitofemoral neuralgia and other pain originating from the testicles, groin, or abdomen. The incidence of patients with CTP, also referred to as orchialgia, orchidynia, or chronic scrotal pain, is large and may be caused by on-going inflammation of the testicle (orchitis) or epididymis (epdidymitis), trauma, tumors, hernia, torsion (twisting of the testicle), varicocele, hydrocele, spermatocele polyarteritis nodosa, and previous surgical interventions such as vasectomy and hernia surgery.
[0008] Typically, testicle removal and spermatic cord denervation procedures are used to treat CTP. In spermatic cord denervation procedures, nerves in or adjacent to the spermatic cord, i.e., the genitofemoral nerve or sympathetic nerves, are severed or permanently removed. Such procedures may result in permanent and substantial pain relief regardless of the origin of pain. However, severing or removing these nerves may result in loss of sensation in the testicle and/or scrotum, loss of the cremasteric reflex which may cause fertility issues, and even loss of blood flow causing the testicle to die. Therapeutic nerve blocks may also be used to treat CTP, but generally only relieve pain temporarily.
[0009] Chronic pelvic pain is also a common medical problem affecting women today. Sources of pain may include injury to nerves resulting from surgical procedures, non-surgical conditions, vulvodynia which can be very debilitating but has no obvious source, and interstitial cystitis (painful bladder syndrome). Surgical procedures that may injure nerves in the pelvic region resulting in pelvic pain may include urological operations in the pelvic area, gynecological surgery, and hysterectomy. Non-surgical conditions which cause pain in women include adhesions, endometriosis, and pelvic congestion. Irritable bowel syndrome may also be considered a chronic pelvic pain condition. Surgical procedures aimed at removing the suspected painful bladder have generally been unsuccessful and often result in worsening of the pain state. This result suggests that the chronic pain state has extended beyond the peripheral organ and may involve central sensitization with the spinal cord that receives sensory input from the peripheral organs.
[0010] One known class of pharmaceuticals used to treat pain is opioids. This class of compounds is well-recognized as being among the most effective type of drugs for controlling pain, such as post-operative pain. Unfortunately, because opioids are administered systemically, the associated side effects raise significant concerns, including disabling the patient, depressing the respiratory system, constipation, and psychoactive effects such as sedation and euphoria, thereby instituting a hurdle to recovery and regained mobility. Consequently, physicians typically limit the administration of opioids to within the first twenty-four hours post-surgery. Although opioids may be used to manage severe episodes of chronic pelvic pain, chronic opioid use may be associated with the development of tolerance leading to the need for higher doses to produce sustained analgesic effects. They may also be associated with addiction.
[0011] One class of pharmaceutical agents are benzodiazepines, which act on the central nervous system to produce various levels of sedative-hypnotic, muscle-relaxant, anxiolytic, and anticonvulsant effects. The members of this class function by interacting with various subunits of the GABA A receptor that regulates the flux of chloride ions across neuronal cell membranes. Benzodiazepines do not directly activate the GABA A receptors but instead modulate the receptor thereby enhancing the effects of the endogenous agonist, gamma-amino-butyric acid (GABA); GABA is the major inhibitory neurotransmitter in the central nervous system. As a class, benzodiazepines are all lipophilic in the nonionized state. Benzodiazepines are often subcategorized by their duration of effect from ultra-short acting to long-acting agents and are available in oral, intramuscular, intravenous, and rectal formulations. Specific drugs that are members of the benzodiazepine class include alprazolam, chlordiazepoxide, clonazeparn, chlorazepate, diazepam, estazolam, flurazepam, halazepam, lorazepam, midazolam, oxazepam, quazepam, temazepam, and triazilam.
[0012] One specific benzodiazepine that is well known to the medical profession is midazolam, which is widely recognized as an ultra short-acting benzodiazepine derivative. It has potent anxiolytic, amnestic, hypnotic, anticonvulsant, skeletal muscle relaxant, and sedative properties. In general, midazolam, also referred to as 8-chloro-6-(2-fluorophenyl)-1-methyl-4H-imidazo[1,5-a][1,4]benzodiazepine (C 18 H 13 ClFN 3 ), may be represented by the following chemical structure:
[0000]
[0013] Midazolam has been used historically to produce both local and regional anesthesia. Midazolam acts on the benzodiazepine binding site of GABA A receptors. When bound it enhances the binding of GABA to the GABA A receptor which results in inhibitory effects on the central nervous system. It can be administered intraspinally (epidural or intrathecal) to treat the spinal cord and provide analgesia for pelvic operations, child delivery, and post surgical recovery. Midazolam is only available as injectable formulations.
[0014] There is a need to develop effective formulations of this class of compounds for this application that provide sustained release of benzodiazepines, such as midazolam, thereby provided prolonged pain relief.
SUMMARY
[0015] Compositions and methods are provided comprising a benzodiazepine that are administered in order to treat prolonged episodes of pain, such as that associated with chronic pelvic pain conditions. The compositions and methods of the present invention may also for example be used to treat pain due to a spinal disc herniation (i.e., sciatica), spondilothesis, stenosis, osteoarthritis, carpal/tarsal tunnel syndrome, tendonitis, temporomandibular joint disorder (TMJ) and discogenic back pain and joint pain, as well as pain that accompanies or follows surgery.
[0016] In one embodiment, an implantable drug depot useful for reducing, preventing or treating pain, such as chronic pelvic pain, in a patient in need of such treatment is provided. The drug depot comprises a polyorthoester (“POE”) and a therapeutically effective amount of a benzodiazepine. The drug depot is administered intraspinally to reduce, prevent or treat pain. The drug depot is capable of releasing the benzodiazepine in an amount between 5 and 50 mg per day for a period of 30 to 135 days. The benzodiazepine may be present in an amount of about 1 to about 50 wt. % of the drug depot.
[0017] In another embodiment, a pharmaceutical formulation comprising a benzodiazepine, wherein the benzodiazepine comprises from about 1 wt. % to about 50 wt. %, 10 wt. % to about 40 wt. % or about 20 wt. % to about 35 wt. % of the formulation, and a polyorthoester is provided. The pharmaceutical composition may for example, be part of a drug depot. The drug depot may: (i) consist of only the benzodiazepine and the polyorthoester; or (ii) consist essentially of the benzodiazepine and the polyorthoester; or (iii) comprise the benzodiazepine, the polyorthoester and one or more other active ingredients, surfactants, excipients or other ingredients or combinations thereof. When there are other active ingredients, surfactants, excipients or other ingredients or combinations thereof in the formulation, in some embodiments these other compounds or combinations thereof comprise less than 20 wt. %, less than 19 wt. %, less than 18 wt. %, less than 17 wt. %, less than 16 wt. %, less than 15 wt. %, less than 14 wt. %, less than 13 wt. %, less than 12 wt. %, less than 11 wt. %, less than 10 wt. %, less than 9 wt. %, less than 8 wt. %, less than 7 wt. %, less than 6 wt. %, less than 5 wt. %, less than 4 wt. %, less than 3 wt. %, less than 2 wt. %, less than 1 wt. % or less than 0.5 wt. % of the drug depot. The drug depot is capable of releasing the benzodiazepine over a period of at least thirty days.
[0018] According to another embodiment, there is an implantable drug depot for reducing, preventing or treating chronic pelvic pain in a patient in need of such treatment, the implantable drug depot comprising a benzodiazepine in an amount of from about 1 wt. % to about 50 wt. % of the drug depot and a polyorthoester in an amount of at least 50 wt. % of the drug depot.
[0019] In still another embodiment, a method for treating pain, such as chronic pelvic pain, is provided. The method comprises implanting a drug depot intraspinally in an organism to reduce, prevent or treat chronic pelvic pain. The drug depot comprises a benzodiazepine and a polyorthoester. The benzodiazepine is present in an amount from about 1 wt. % to about 50 wt. %, about 10 wt. % to about 40 wt. % or about 20 wt. % to about 35 wt. % of the drug depot.
[0020] In still yet another embodiment, an implantable drug depot comprising a therapeutically effective amount of a benzodiazepine and a polyorthoester is provided. The drug depot is capable of releasing an initial bolus dose of the midazolam at a site beneath the skin of a patient, and the drug depot is capable of releasing a sustained release dose of an effective amount of the midazolam over a subsequent period of 30 to 135 days. The benzodiazepine comprises about 1 wt. % to about 50 wt. % of the total wt. % of the drug depot and the polyorthoester comprises at least about 50 wt. % of the drug depot.
[0021] In another embodiment, a method of making an implantable drug depot is provided. The method comprises combining a polyorthoester and a therapeutically effective amount of a benzodiazepine and forming an implantable drug depot from the combination.
[0022] In various embodiments, the benzodiazepine may be in the form of a base. Alternatively, the benzodiazepine may be in the form of a salt. One example of a salt is a hydrochloride salt. The benzodiazepine may also be in the form of a mixture of a hydrochloride salt and free base.
[0023] The drug depot in various embodiments may comprise a hydrophilic agent, such as baclofen, to help control release and/or provide a co-therapeutic effect.
[0024] The benzodiazepine in the various embodiments is capable of being released in an amount between 0.25 and 10 mg per day for a period of 30 to 180 days. The drug depot in the various embodiments is capable of releasing about 5% to about 100% of the benzodiazepine relative to a total amount of the benzodiazepine loaded in the drug depot over a period of 30 to 200 days after the drug depot is implanted in the organism.
[0025] The benzodiazepine in various embodiments is selected from the group consisting of alprazolam, chlordiazepoxide, clonazepam, chlorazepate, diazepam, estazolam, flurazepam, halazepam, lorazepam, midazolam, oxazepam, quazepam, temazepam, triazilam, and combinations thereof. In some embodiments, the benzodiazepine is medazolam.
[0026] The polyorthoester in the various embodiments may comprise about 50 wt. % to about 99 wt. % of the total wt. % of the drug depot. The polyorthoester is capable of degrading or degrades in 200 days or less after the drug depot is implanted at a site.
[0027] The drug depot in the various embodiments may further comprise one or more of polyaspirin, polyphosphazene, polyanhydride; polyketal, collagen, starch, pre-gelatinized starch, hyaluronic acid, chitosan, gelatin, alginate, albumin, fibrin, vitamin E analog, d-alpha tocopheryl succinate, poly-ε-caprolactone, dextran, polyvinylpyrrolidone, polyvinyl alcohol, PEGT-PBT copolymer, PEO-PPO-PEO, sucrose acetate isobutyrate, a different polyorthoester or a combination thereof.
[0028] The drug depot in various embodiments may comprise a radiographic marker adapted to assist in radiographic imaging. The radiographic marker may comprise barium, bismuth, tantalum, tungsten, iodine, calcium phosphate, and/or metal beads. The drug depot in various embodiments is capable of releasing between 0.25 and 10 milligrams (mg) per day of a benzodiazepine to reduce, prevent or treat chronic pelvic pain.
[0029] The target site in the various embodiments comprises the lumbosacral epidural space or at least one muscle, ligament, tendon, cartilage, spinal disc, spinal foraminal space near the spinal nerve root, facet or synovial joint, or spinal canal.
[0030] The pain may be associated with pelvic pain such as interstitial cystitis or chronic nobacterial prostatitis, hernia repair, orthopedic or spine surgery or a combination thereof. The surgery may be arthroscopic surgery, an excision of a mass, hernia repair, spinal fusion, thoracic, cervical, or lumbar surgery, pelvic surgery or a combination thereof.
[0031] Additional features and advantages of various embodiments will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practice of various embodiments. The objectives and other advantages of various embodiments will be realized and attained by means of the elements and combinations particularly pointed out in the description and appended claims.
DETAILED DESCRIPTION
[0032] For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing quantities of ingredients, percentages or proportions of materials, reaction conditions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
[0033] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a range of “1 to 10” includes any and all subranges between (and including) the minimum value of 1 and the maximum value of 10, that is, any and all subranges having a minimum value of equal to or greater than 1 and a maximum value of equal to or less than 10, e.g., 5.5 to 10.
Definitions
[0034] It is noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the,” include plural referents unless expressly and unequivocally limited to one referent. Thus, for example, reference to “a drug depot” includes one, two, three or more drug depots.
[0035] A “drug depot” is the composition in which the midazolam is administered to the body. Thus, a drug depot may comprise a physical structure to facilitate implantation and retention in a target site. The drug depot may also comprise the drug itself. The term “drug” as used herein is generally meant to refer to any substance that alters the physiology of a patient. The term “drug” may be used interchangeably herein with the terms “therapeutic agent,” “therapeutically effective amount,” and “active pharmaceutical ingredient” or “API.” It will be understood that unless otherwise specified a “drug” formulation may include more than one therapeutic agent, wherein exemplary combinations of therapeutic agents include a combination of two or more drugs. The drug depot provides a concentration gradient of the therapeutic agent for delivery to the target site.
[0036] “Target site” as used herein is used to refer to an area of the body to which the drug is administered. Target sites desirably used with the methods of this invention include specific regions within the spinal canal. As used herein, the term “spinal region” includes the spinal canal (including the spinal cord, intrathecal space, dura, epidural space, etc.), vertebrae, spinal discs, nerve roots, and the ligaments, tendons and muscles in between and surrounding the vertebrae. In one embodiment of the invention, the target site is epidural. In other embodiments the target site is in the intrathecal or peridural spaces of the spinal region. The target sites for the administration of a drug to alleviate pelvic pain in subjects also experiencing bladder or pelvic floor disorders is desirably in the epidural, peridural or intrathecal spaces in the spinal region between the sacrum and/or coccyx, desirably between Co1 and L1, between S5 and S1, between S2 and L1, or between T10 and S4. In one embodiment, the target site is the spinal region that may be accessed through the sacral hiatus or the sacral foramen.
[0037] A “therapeutically effective amount” or “effective amount” is such that when administered, the drug results in alteration of the biological activity, such as, for example, inhibition of inflammation, reduction or alleviation of pain or spasticity, improvement in the condition through muscle relaxation, etc. The dosage administered to a patient can be as single or multiple doses depending upon a variety of factors, including the drug's administered pharmacokinetic properties, the route of administration, patient conditions and characteristics (sex, age, body weight, health, size, etch), extent and duration of symptoms, concurrent treatments, frequency of treatment and the effect desired. In some embodiments, the formulation is designed for sustained release. In other embodiments, the formulation comprises one or more immediate release surfaces and one or more sustained release surfaces.
[0038] A “depot” includes but is not limited to capsules, microspheres, microparticles, microcapsules, microfibers particles, nanospheres, nanoparticles, coating, matrices, wafers, pills, pellets, emulsions, liposomes, micelles, gels, or other pharmaceutical delivery compositions or a combination thereof. Suitable materials for the depot are ideally pharmaceutically acceptable biodegradable and/or any bioabsorbable materials that are preferably FDA approved or GRAS materials. These materials can be polymeric or non-polymeric, as well as synthetic or naturally occurring, or a combination thereof.
[0039] As used herein, “biodegradable” and “bioerodible” are used interchangeably and are intended to broadly encompass materials including, for example, those that tend to break down upon exposure to physiological environments. Biodegradable and/or bioerodible polymers known in the art include, for example, linear aliphatic polyester homopolymers (e.g., polyglycolide, polylactide, polycaprolactone, and polyhydroxybutyrate) and copolymers (e.g., poly(glycolide-co-lactide), poly(glycolide-co-caprolactone), poly(glycolide-co-trimethylenecarbonate), poly(lactic acid-co-lysine), poly(lactide-co-urethane), poly(ester-co-amide)); polyanhydrides; polyketals; and poly(orthoesters), “Biocompatible” means that the depot will not cause substantial tissue irritation or necrosis at the target tissue site.
[0040] The phrases “sustained release” and “sustain release” (also referred to as extended release or controlled release) are used herein to refer to one or more therapeutic agent(s) that is introduced into the body of a human or other mammal and continuously or continually release an amount of one or more therapeutic agents over a predetermined time period and at a therapeutic level sufficient to achieve a desired therapeutic effect throughout the predetermined time period. Reference to a continuous or continual release is intended to encompass release that occurs as the result of biodegradation in vivo of the drug depot, or a matrix or component thereof, or as the result of metabolic transformation or dissolution of the therapeutic agent(s) or conjugates of therapeutic agent(s).
[0041] The phrase “immediate release” is used herein to refer to one or more therapeutic agent(s) that is introduced into the body and that is allowed to dissolve in or become absorbed at the location to which it is administered, with no intention of delaying or prolonging the dissolution or action of the drug.
[0042] The two types of formulations (sustain release and immediate release) may be used in conjunction. The sustained release and immediate release may be in one or more of the same depots. In various embodiments, the sustained release and immediate release may be part of separate depots. For example, a bolus or immediate release formulation of midazolam may be placed at or near the target site and a sustain release formulation may also be placed at or near the same site. Thus, even after the bolus becomes completely exhausted, the sustain release formulation would continue to provide the active ingredient for the intended tissue.
[0043] In various embodiments, the drug depot can be designed to cause an initial burst dose of therapeutic agent within the first twenty-four hours after implantation. “Initial burst” or “burst effect” refers to the release of therapeutic agent from the depot during the first twenty-four hours after the depot comes in contact with a biological fluid (e.g., interstitial fluid, synovial fluid, cerebrospinal fluid, etc.). The “burst effect” is believed to be due to the increased release of therapeutic agent from the depot. In alternative embodiments, the depot is designed to avoid this initial burst effect.
[0044] “Treating” or “treatment” of a disease or condition refers to executing a protocol that may include administering one or more drugs to a patient (human, or other mammal), in an effort to alleviate or eliminate signs or symptoms of the disease or condition. Alleviation can occur prior to signs or symptoms of the disease or condition appearing, as well as after their appearance. Thus, treating or treatment includes preventing or prevention of disease or undesirable condition. In addition, treating or treatment does not require complete alleviation of signs or symptoms, does not require a cure, and specifically includes protocols that have only a marginal effect on the patient.
[0045] “Localized” delivery includes delivery where one or more drugs are deposited within or near a tissue, for example, a nerve root of the nervous system or a region of the spinal cord, or in close proximity (within about 0.1 cm, or preferably within about 1.0 cm, for example) thereto.
[0046] The term “mammal” refers to organisms from the taxonomic class “mammalia,” including but not limited to humans, other primates such as chimpanzees, apes, orangutans and monkeys, rats, mice, cats, dogs, cows, horses, etc.
[0047] The phrase “pain management medication” includes one or more therapeutic agents that are administered to prevent, alleviate or remove pain entirely. These include anti-inflammatory agents, muscle relaxants, analgesics, anesthetics, narcotics, and so forth, and combinations thereof.
[0048] The phrase “release rate” refers to the percentage of active ingredient that is released over fixed units of time, e.g., mcg/hr, mcg/day, 10% per day for ten days, etc. As persons of ordinary skill know, a release rate profile may, but need not, be linear. By way of a non-limiting example, the drug depot may be a ribbon-like fiber that releases the midazolam over a period of time.
[0049] The term “solid” is intended to mean a rigid material, while, “semi-solid” is intended to mean a material that has some degree of flexibility, thereby allowing the depot to bend and conform to the surrounding tissue requirements.
[0050] The term “gel” is intended to mean a semi-solid material that may be flowable upon application to the target site, then may harden or increase in viscosity upon delivery.
[0051] “Targeted delivery system” provides delivery of one or more drug depots, gels or depots dispersed in the gel having a quantity of therapeutic agent that can be deposited at or near the target site as needed for treatment of pain, inflammation or other disease or condition.
[0052] Reference will now be made in detail to certain embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the illustrated embodiments, it will be understood that they are not intended to limit the invention to those embodiments. On the contrary, the invention is intended to cover all alternatives, modifications, and equivalents that may be included within the invention as defined by the appended claims.
[0053] The headings below are not meant to limit the disclosure in any way; embodiments under any one heading may be used in conjunction with embodiments under any other heading.
Benzodiazepine
[0054] In various embodiments, the benzodiazepine is selected from the group consisting of alprazolam, chlordiazepoxide, clonazepam, chlorazepate, diazepam, estazolam, flurazepam, halazepam, lorazepam, midazolam, oxazepam, quazepam, temazepam, triazilam, and combinations thereof. In some embodiments, the benzodiazepine is midazolam.
[0055] When referring to benzodiazepines, such as midazolam, the active ingredient may be in the salt form or the base form (e.g., free base). In various embodiments, if it is in the base form, it may be combined with a polymer such as a polyorthoester under conditions in which there is not significant polymer degradation. By way of a non-limiting example, when formulating a benzodiazepine, such as midazolam, with a polyorthoester, it may be desirable to use the base formulation.
[0056] Further, the benzodiazepine, such as midazolam, may be in the salt form and one well-known commercially available salt for midazolam is its hydrochloride salt. Some other examples of potentially pharmaceutically acceptable salts include those salt-forming acids that do not substantially increase the toxicity of a compound, such as, salts of mineral acids such as hydriodic, hydrobromic, phosphoric, metaphosphoric, nitric and sulfuric acids, as well as salts of organic acids such as tartaric, acetic, citric, malic, benzoic, glycolic, gluconic, gulonic, succinic, arylsulfonic, e.g., p-toluenesulfonic acids, and the like.
[0057] The benzodiazepine may also be administered with other suitable analgesic agents that include, but are not limited to, acetaminophen, clonidine, bupivacaine, opioid analgesics such as buprenorphine, butorphanol, dextromoramide, dezocine, dextropropoxyphene, diamorphine, fentanyl, alfentanil, sufentanil, hydrocodone, hydromorphone, ketobemidone, levomethadyl, mepiridine, methadone, morphine, nalbuphine, opium, oxycodone, papavereturn, pentazocine, pethidine, phenoperidine, piritramide, dextropropoxyphene, remifentanil, tilidine, tramadol, codeine, dihydrocodeine, meptazinol, dezocine, eptazocine, and nonopioid analgesics such as flupirtine, amitriptyline, carbamazepine, gabapentin, pregabalin, or a combination thereof.
[0058] The benzodiazepine, such as midazolam, may also be administered with non-active ingredients. These non-active ingredients may have multi-functional purposes including the carrying, stabilizing and controlling of the release of the therapeutic agent(s). The sustained release process, for example, may be by a solution-diffusion mechanism or it may be governed by an erosion-sustained process. Typically, the depot will be a solid or semi-solid formulation comprised of a biocompatible material that can be biodegradable.
[0059] Exemplary excipients that may be formulated with bupivacaine in addition to the biodegradable polymer include but are not limited to MgO, PEG, MPEG, Span-65, Span-85, pluronic F127, TBO-Ac, sorbital, cyclodextrin, maltodextrin, maltose, mannitol, pluronic F68, CaCl 2 , and combinations thereof. In some embodiments, the excipients comprise from about 0.001 wt. % to about 50 wt. % of the formulation. In some embodiments, the excipients comprise from about 0.001 wt. % to about 40 wt. % of the formulation. In some embodiments, the excipients comprise from about 0.001 wt. % to about 30 wt. % of the formulation. In some embodiments, the excipients comprise from about 0.001 wt. % to about 20 wt. % of the formulation. In some embodiments, the excipients comprise from about 0.1 wt. % to about 10 wt. % of the formulation. In some embodiments, the excipients comprise from about 0.001 wt. % to about 2 wt. % of the formulation. In some embodiments, the excipients comprise from about 0.1 wt. % to about 5 wt. % of the formulation. In some embodiments, the excipients comprise from about 0.1 wt. % to about 2 wt. % of the formulation.
[0060] In various embodiments, the depot may comprise a biodegradeable polyorthoester. The mechanism of the degradation process of the polyorthoester can be hydrolytic. In various embodiments, the degradation can occur either at the surface (heterogeneous or surface erosion) or uniformly throughout the drug delivery system depot (homogeneous or bulk erosion). Polyorthoester materials can be obtained from A.P. Pharma, Inc. (Redwood City, Calif.) or through the reaction of a bis(ketene acetal) such as 3,9-diethylidene-2,4,8,10-tetraoxospiro[5,5]undecane (DETOSU) with suitable combinations of diol(s) and/or polyol(s) such as 1,4-trans-cyclohexanedimethanol and 1,6-hexanediol or by any other chemical reaction that produces a polymer comprising orthoester moieties. Some exemplary polyorthoester materials suitable for use in the present invention are described in U.S. patent Application Publication Number 2008/0033140, entitled “Poly(Orthoester) Polymers, and Methods of Making and Using Same” which is hereby incorporated by reference in its entirety.
[0061] In some embodiments, the drug depot may not be completely biodegradable. For example, the drug depot may comprise polyorthoester and one of more of the following: polyurethane, polyurea, polyether(amide), PEBA, thermoplastic elastomeric olefin, copolyester, and styrenic thermoplastic elastomer, steel, aluminum, stainless steel, titanium, metal alloys with high non-ferrous metal content and a low relative proportion of iron, carbon fiber, glass fiber, plastics, ceramics or combinations thereof. Typically, these types of drug depots may need to be removed after a certain amount of time.
[0062] In various embodiments, the depot may comprise a bioerodable, a bioabsorbable, and/or a biodegradable biopolymer in addition to a polyorthoester that may provide immediate release, or sustained release of the benzodiazepine. The biopolymer may also include one or more of the following biopolymers: polyaspirins, polyphosphazenes, polyanhydrides; polyketals, collagen, starch, pre-gelatinized starch, hyaluronic acid, chitosans, gelatin, alginates, albumin, fibrin, vitamin E analogs, such as alpha tocopheryl acetate, d-alpha tocopheryl succinate, poly-ε-caprolactone, dextrans, polyvinylpyrrolidone, polyvinyl alcohol (PVA), PEGT-PBT copolymer (PolyActive®), PEO-PPO-PEO (Pluronics®), Poloxamer 407, SAIB (sucrose acetate isobutyrate), a different polyorthoester or other biodegradeable polymer or combinations thereof. As persons of ordinary skill are aware, MPEG may be used as a plasticizer for a POE, but other polymers/excipients may be used to achieve the same effect. mPEG imparts malleability to the resulting formulations.
[0063] The depot may optionally contain inactive materials such as buffering agents and pH adjusting agents such as potassium bicarbonate, potassium carbonate, potassium hydroxide, sodium acetate, sodium borate, sodium bicarbonate, sodium carbonate, sodium hydroxide, sodium phosphate, magnesium oxide or magnesium carbonate; degradation/release modifiers; drug release adjusting agents; emulsifiers; preservatives such as benzalkonium chloride, chlorobutanol, phenylmercuric acetate and phenylmercuric nitrate, sodium bisulfate, sodium bisulfite, sodium thiosulfate, thimerosal, methylparaben, polyvinyl alcohol and phenylethyl alcohol; solubility adjusting agents; stabilizers; and/or cohesion modifiers. If the depot is to be placed in the spinal area, in various embodiments, the depot may comprise sterile preservative free material.
[0064] The depot can be of different sizes, shapes and configurations. There are several factors that can be taken into consideration in determining the size, shape and configuration of the drug depot. For example, both the size and shape may allow for ease in positioning the drug depot at the target tissue site that is selected as the implantation or injection site. In some embodiments, the shape and size of the system should be selected so as to minimize or prevent the drug depot from moving after implantation or injection. In various embodiments, the drug depot can be shaped like a sphere, a pellet, a cylinder such as a rod or fiber, a flat surface such as a disc, film or sheet (e.g., ribbon-like) or the like. Flexibility may be a consideration so as to facilitate placement of the drug depot. In one embodiment, the drug depot has the shape of a ribbon and has a length of from about 10 mm to 200 mm. In another embodiment, the drug depot is in the form of microspheres having an average diameter from about 1 micron to about 500 microns, more specifically from about 1 micron to about 250 microns, more specifically, from about 1 micron to about 150 microns, and more specifically from about 10 microns to about 100 microns.
[0065] Radiographic markers can be included on the drug depot to permit the user to position the depot accurately into the target site of the patient. These radiographic markers will also permit the user to track movement and degradation of the depot at the site over time. In this embodiment, the user may accurately position the depot in the site using any of the numerous diagnostic imaging procedures. Such diagnostic imaging procedures include, for example, X-ray imaging or fluoroscopy. Examples of such radiographic markers include, but are not limited to, barium, bismuth, tantalum, tungsten, iodine, calcium phosphate, and/or metal beads or particles. In various embodiments, the radiographic marker could be a spherical shape or a ring around the depot.
[0066] In some embodiments, the drug depot has pores that control release of the drug from the depot. The pores allow fluid into the depot to displace and/or dissolve the drug.
Gel
[0067] In various embodiments, midazolam and polyorthoester are administered with or in a gel. The gel may have a pre-dosed viscosity in the range of about 1 to about 200,000 centipoise (cP), 100 to about 20,000 cP, or 500 to about 10,000 cP. After the gel is administered to the target site, the viscosity of the gel will increase and the gel will have a modulus of elasticity (Young's modulus) in the range of about 1×10 2 to about 6×10 5 dynes/cm 2 , or 2×10 4 to about 5×10 5 dynes/cm 2 , or 5×10 4 to about 5×10 5 dynes/cm 2 .
[0068] The gel may be of any suitable type, as previously indicated, and should be sufficiently viscous so as to prevent the gel from migrating from the targeted delivery site once deployed; the gel should, in effect, “stick” or adhere to the targeted tissue site or conform to the target tissue space. The gel may, for example, solidify upon contact with the targeted tissue or after deployment from a targeted delivery system. The targeted delivery system may be, for example, a syringe, a catheter, sheath, needle or cannula or any other suitable device. The targeted delivery system may inject the gel into or on the targeted site. The therapeutic agent may be mixed into the gel prior to the gel being deployed at the targeted site. In various embodiments, the gel may be part of a two-component delivery system and when the two components are mixed, a chemical process is activated to form the gel and cause it to stick or to adhere to the target site.
[0069] The gel may harden or stiffen after delivery. Typically, hardening gel formulations may have a pre-dosed modulus of elasticity in the range of about 1×10 2 to about 3×10 5 dynes/cm 2 , or 2×10 2 to about 2×10 5 dynes/cm 2 , or 5×10 2 to about 1×10 5 dynes/cm 2 . The post-dosed hardening gels (after delivery) may have a rubbery consistency and have a modulus of elasticity in the range of about 1×10 4 to about 2×10 5 dynes/cm 2 , or 1×10 5 to about 7×10 5 dynes/cm 2 , or 2×10 5 to about 5×10 5 dynes/cm 2 .
[0070] If the gel includes the benzodiazepine, such as midazolam, and a polyorthoester, the polyorthoester concentration may affect the rate at which the gel hardens (e.g., a gel with a higher concentration of polymer may coagulate more quickly than gels having a lower concentration of polymer). In various embodiments, when the gel hardens, the resulting matrix is solid but is also able to conform to the irregular surface of the target site.
[0071] The percentage of polyorthoester present in the gel may also affect the viscosity of the polymeric composition. For example, a composition having a higher percentage by weight of polymer is typically thicker and more viscous than a composition having a lower percentage by weight of polymer. A more viscous composition tends to flow more slowly. Therefore, a composition having a lower viscosity may be preferred in some instances. In some embodiments, the polyorthoester comprises 20 wt. % to 90 wt. % of the formulation.
[0072] In various embodiments, the molecular weight of the polymers that make up the gel can be varied by many methods known in the art. The choice of method to vary molecular weight is typically determined by the composition of the gel (e.g., polymer, versus non-polymer). For example, in various embodiments, the degree of polymerization can be controlled by varying the amount of polymer initiators (e.g. benzoyl peroxide), organic solvents or activator (e.g. DMPT), crosslinking agents, polymerization agent, reaction time and/or by including chain transfer or chain terminating agents.
[0073] The gel can vary from low viscosity, similar to that of water, to high viscosity, similar to that of a paste, depending on the molecular weight and concentration of the polyorthoester used in the gel. The viscosity of the gel can be varied such that the composition can be applied to a patient's tissues by any convenient technique, for example, by brushing, dripping, injecting, or painting. Different viscosities of the gel are selected to conform to the technique used to deliver the composition.
[0074] The gel may optionally have a viscosity enhancing agent such as, for example, hydroxypropyl cellulose, hydroxypropyl methylcellulose, hydroxyethyl methylcellulose, carboxymethylcellulose and salts thereof, Carbopol, poly-(hydroxyethylmethacrylate), poly-(methoxyethylmethacrylate), poly(methoxyethoxyethyl methacrylate), polymethylmethacrylate (PMMA), methylmethacrylate (MMA), gelatin, polyvinyl alcohols, propylene glycol, NiPEG, PEG 200, PEG 300, PEG 400, PEG 500, PEG 600, PEG 700, PEG 800, PEG 900, PEG 1000, PEG 1450, PEG 3350, PEG 4500, PEG 8000 or combinations thereof.
Drug Delivery
[0075] It will be appreciated by those with skill in the art that the depot can be administered to the target site using a catheter or a “cannula”, “trocar” or “needle” that can be a part of a drug delivery device e.g., a syringe, a gun drug delivery device, or any medical device suitable for the application of a drug to a targeted site. The catheter, cannula, trocar or needle of the drug depot device is designed to cause minimal physical and psychological trauma to the patient.
[0076] Catheters, cannulas, trocars or needles include tubes that may be made from materials, such as for example, polyurethane, polyurea, polyether(amide), PEBA, thermoplastic clastomeric olefin, copolyester, and styrenic thermoplastic elastomer, steel, aluminum, stainless steel, titanium, metal alloys with high non-ferrous metal content and a low relative proportion of iron, carbon fiber, glass fiber, plastics, ceramics or combinations thereof. The cannula or needle may optionally include one or more tapered regions. In various embodiments, the cannula or needle may be beveled. The cannula or needle may also have a tip style vital for accurate treatment of the patient depending on the site for implantation. Examples of tip styles include, for example, Trephine, Cournand, Veress, Huber, Seldinger, Chiba, Francine, Bias, Crawford, deflected tips, Hustead, Lancet, or Tuohey. In various embodiments, the cannula or needle may also be non-coring and have a sheath covering it to avoid unwanted needle sticks.
[0077] The dimensions of the hollow cannula or needle, among other things, will depend on the site for implantation. For example, the width of the epidural space is only about 3-5 mm for the thoracic region and about 5-7 mm for the lumbar region. Thus, the needle or cannula, in various embodiments, can be designed for these specific areas.
[0078] Some examples of lengths of the cannula or needle may include, but are not limited to, from about 50 to 150 mm in length, for example, about 65 mm for epidural pediatric use, about 85 mm for a standard adult and about 110 mm for an obese adult patient. The diameter of the cannula or needle will also depend on the site of implantation. In various embodiments, the diameter includes, but is not limited to, from about 0.05 to about 1.655 (mm). The gauge of the cannula or needle may be the widest or smallest diameter or a diameter in between for insertion into a human or animal body. The widest diameter is typically about 14 gauge, while the smallest diameter is about 22 gauge. In various embodiments, the gauge of the needle or cannula is about 18 to about 22 gauge. In some embodiments, the needle or cannula may include two lumens; one for administering the drug depot and a second for administering a radiocontrast agent. This allows both to be administered without having to reposition the needle.
[0079] In various embodiments, like the drug depot and/or gel, the cannula or needle includes dose radiographic markers that indicate location at or near the site beneath the skin, so that the user may accurately position the depot at or near the site using any of the numerous diagnostic imaging procedures. Such diagnostic imaging procedures include, for example, X-ray imaging or fluoroscopy. Examples of such radiographic markers include, but are not limited to, barium, bismuth, tantalum, tungsten, iodine, gold, calcium, and/or metal beads or particles.
[0080] In various embodiments, the needle or cannula may include a transparent or translucent portion that can be visualized by ultrasound, fluoroscopy, X-ray, or other imaging techniques. In such embodiments, the transparent or translucent portion may include a radiopaque material or ultrasound responsive topography that increases the contrast of the needle or cannula relative to the absence of the material or topography.
[0081] The drug depot, and/or medical device to administer the drug may be sterilizable. In various embodiments, one or more components of the drug depot, and/or medical device to administer the drug are sterilized by radiation in a terminal sterilization step in the final packaging. Terminal sterilization of a product provides greater assurance of sterility than from processes such as an aseptic process, which require individual product components to be sterilized separately and the final package assembled in a sterile environment.
[0082] In various embodiments, a kit is provided that may include additional parts along with the drug depot and/or medical device combined together to be used to implant the drug depot. The kit may include the drug depot device in a first compartment. The second compartment may include a canister holding the drug depot and any other instruments needed for the localized drug delivery. A third compartment may include gloves, drapes, wound dressings and other procedural supplies for maintaining sterility of the implanting process, as well as an instruction booklet. A fourth compartment may include additional cannulas and/or needles. A fifth compartment may include an agent for radiographic imaging. Each tool may be separately packaged in a plastic pouch that is radiation sterilized. A cover of the kit may include illustrations of the implanting procedure and a clear plastic cover may be placed over the compartments to maintain sterility.
[0083] In one embodiment, the drug depot is desirably delivered to the lumbosacral spinal region. A depot may be delivered to that space via a drug delivery catheter. The techniques for such delivery method are well known in the art. In one embodiment, the Seldinger technique is used and an introducer having a lumen is used to enter the spinal space through one of the sacral hiatuses or sacral foramina, a guidewire is passed through the introducer, the introducer is removed and the catheter is advanced over the wire until it is in position for drug delivery.
[0084] In various embodiments, to administer the gel having the drug depot dispersed therein to the desired site, first the cannula or needle can be inserted through the skin and soft tissue down to the target site and the gel administered at or near the target site. In those embodiments where the drug depot is separate from the gel, first the cannula or needle can be inserted through the skin and soft tissue down to the site of injection and one or more base layer(s) of gel can be administered to the target site. Following administration of the one or more base layer(s), the drug depot can be implanted on or in the base layer(s) so that the gel can hold the depot in place or reduce migration. If required, a subsequent layer or layers of gel can be applied on the drug depot to surround the depot and further hold it in place. Alternatively, the drug depot may be implanted first and then the gel placed around the drug depot to hold it in place. By using the gel, accurate and precise implantation of a drug depot can be accomplished with minimal physical and psychological trauma to the patient. The gel also avoids the need to suture the drug depot to the target site reducing physical and psychological trauma to the patient.
[0085] The formulations of the present application may be used as medicaments in the form of pharmaceutical preparations. The preparations may be formed in an administration with a suitable pharmaceutical carrier that may be solid or liquid and organic or inorganic, and placed in the appropriate form for parenteral or other administration as desired. As persons of ordinary skill are aware, known carriers include but are not limited to water, gelatin, lactose, starches, stearic acid, magnesium stearate, talc, vegetable oils, benzyl alcohols, gums, waxes, propylene glycol, polyalkylene glycols and other known carriers for medicaments.
[0086] In some embodiments, the benzodiazepine and polyorthoester formulations are suitable for parenteral administration. The term “parenteral” as used herein refers to modes of administration that bypass the gastrointestinal tract, and include for example, intravenous, intramuscular, continuous or intermittent infusion, intraperitoneal, intrasternal, subcutaneous, intra-operatively, intrathecally, intradiskally, peridiskally, epidurally, perispinally, intraarticular injection or combinations thereof. In some embodiments, the injection is intrathecal, which refers to an injection into the spinal canal (subarachnoid space surrounding the spinal cord).
[0087] Various techniques are available for forming at least a portion of a drug depot from the biocompatible polymer(s), therapeutic agent(s), and optional materials, including solution processing techniques and/or thermoplastic processing techniques. Where solution processing techniques are used, a solvent system is typically selected that contains one or more solvent species. The solvent system is generally a good solvent for at least one component of interest, for example, biocompatible polymer and/or therapeutic agent. The particular solvent species that make up the solvent system can also be selected based on other characteristics, including drying rate and surface tension.
[0088] Solution processing techniques include solvent casting techniques, spin coating techniques, web coating techniques, solvent spraying techniques, dipping techniques, techniques involving coating via mechanical suspension, including air suspension (e.g., fluidized coating), ink jet techniques and electrostatic techniques. Where appropriate, techniques such as those listed above can be repeated or combined to build up the depot to obtain the desired release rate and desired thickness.
[0089] In various embodiments, a solution containing a solvent and a biocompatible polymer are combined and placed in a mold of the desired size and shape. In this way, polymeric regions, including barrier layers, lubricious layers, and so forth can be formed. If desired, the solution can further comprise, one or more of the following: the benzodiazepine and other therapeutic agent(s) and other optional additives such as radiographic agent(s), etc. in dissolved or dispersed form. This results in a polymeric matrix region containing these species after solvent removal. In other embodiments, a solution containing solvent with dissolved or dispersed therapeutic agent is applied to a pre-existing polymeric region, which can be formed using a variety of techniques including solution processing and thermoplastic processing techniques, whereupon the therapeutic agent is imbibed into the polymeric region.
[0090] Thermoplastic processing techniques for forming a depot or portions thereof include molding techniques (for example, injection molding, rotational molding, and so forth), extrusion techniques (for example, extrusion, co-extrusion, multi-layer extrusion, and so forth) and casting.
[0091] Thermoplastic processing in accordance with various embodiments comprises mixing or compounding, in one or more stages, the polyorthoester and one or more of the following: the benzodiazepine, optional additional therapeutic agent(s), radiographic agent(s), and so forth. The resulting mixture is then shaped into an implantable drug depot. The mixing and shaping operations may be performed using any of the conventional devices known in the art for such purposes.
[0092] During thermoplastic processing, there exists the potential for the therapeutic agent(s) to degrade, for example, due to elevated temperatures and/or mechanical shear that are associated with such processing. For example, the benzodiazepine may undergo substantial degradation under ordinary thermoplastic processing conditions. Hence, processing is preferably performed under modified conditions, which prevent the substantial degradation of the therapeutic agent(s). Although it is understood that some degradation may be unavoidable during thermoplastic processing, degradation is generally limited to 10% or less. Among the processing conditions that may be controlled during processing to avoid substantial degradation of the therapeutic agent(s) are temperature, applied shear rate, applied shear stress, residence time of the mixture containing the therapeutic agent, and the technique by which the polymeric material and the therapeutic agent(s) are mixed.
[0093] Mixing or compounding a polyorthoester with therapeutic agent(s) and any additional additives to form a substantially homogenous mixture thereof may be performed with any device known in the art and conventionally used for mixing polymeric materials with additives.
[0094] Where thermoplastic materials are employed, a polymer melt may be formed by heating the biocompatible polymer, which can be mixed with various additives (e.g., therapeutic agent(s), inactive ingredients, etc.) to form a mixture. A common way of doing so is to apply mechanical shear to a mixture of the biocompatible polymer(s) and additive(s). Devices in which the biocompatible polymer(s) and additive(s) may be mixed in this fashion include devices such as single screw extruders, twin screw extruders, banbury mixers, high-speed mixers, ross kettles, and so forth.
[0095] Any of the various additives and a polyorthoester may be premixed prior to a final thermoplastic mixing and shaping process, if desired (e.g., to prevent substantial degradation of the therapeutic agent among other reasons).
[0096] For example, in various embodiments, a polyorthoester is precompounded with a radiographic agent (e.g., radio-opacifying agent) under conditions of temperature and mechanical shear that would result in substantial degradation of the therapeutic agent, if it were present. This precompounded material is then mixed with therapeutic agent under conditions of lower temperature and mechanical shear, and the resulting mixture is shaped into the benzodiazepine containing drug depot. Conversely, in another embodiment, the polyorthoester can be precompounded with the therapeutic agent under conditions of reduced temperature and mechanical shear. This precompounded material is then mixed with, for example, a radio-opacifying agent, also under conditions of reduced temperature and mechanical shear, and the resulting mixture is shaped into the drug depot.
[0097] The conditions used to achieve a mixture of the polyorthoester and therapeutic agent and other additives will depend on a number of factors including, for example, the additive(s) used, as well as the type of mixing device used.
[0098] In other embodiments, a polyorthoester and one or more therapeutic agents are premixed using non-thermoplastic techniques. For example, the polyorthoester can be dissolved in a solvent system containing one or more solvent species. Any desired agents (for example, a radio-opacifying agent, a therapeutic agent, or both radio-opacifying agent and therapeutic agent) can also be dissolved or dispersed in the solvents system. Solvent is then removed from the resulting solution/dispersion, forming a solid material. The resulting solid material can then be granulated for further thermoplastic processing (for example, extrusion) if desired.
[0099] As another example, the therapeutic agent can be dissolved or dispersed in a solvent system, which is then applied to a pre-existing polymer matrix (the pre-existing drug depot can be formed using a variety of techniques including solution and thermoplastic processing techniques, and it can comprise a variety of additives including a radio-opacifying agent and/or viscosity enhancing agent), whereupon the therapeutic agent is imbibed on or in the polymer matrix. As above, the resulting solid material can then be granulated for further processing, if desired.
[0100] Typically, an extrusion process may be used to form the drug depot comprising a polyorthoester, therapeutic agent(s) and radio-opacifying agent(s). Co-extrusion may also be employed, which is a shaping process that can be used to produce a drug depot comprising the same or different layers or regions (for example, a structure comprising one or more polymeric matrix layers or regions that have permeability to fluids to allow immediate and/or sustained drug release). Multi-region depots can also be formed by other processing and shaping techniques such as co-injection or sequential injection molding technology.
[0101] In various embodiments, the depot that may emerge from the thermoplastic processing (e.g., pellet) is cooled. Examples of cooling processes include air cooling and/or immersion in a cooling bath. In some embodiments, a water bath is used to cool the extruded depot. However, where a water-soluble therapeutic agent such as midazolam is used, the immersion time should be held to a minimum to avoid unnecessary loss of therapeutic agent into the bath.
[0102] In various embodiments, immediate removal of water or moisture by use of ambient or warm air jets after exiting the bath will also prevent re-crystallization of the drug on the depot surface, thus controlling or minimizing a high drug dose “initial burst” or “bolus dose” upon implantation or insertion if this is release profile is not desired.
[0103] In various embodiments, the drug depot can be prepared by mixing or spraying the drug with the polyorthoester and then molding the depot to the desired shape. In various embodiments, the benzodiazepine is used and mixed or sprayed with a polyorthoester, and the resulting depot may be formed by extrusion and dried.
[0104] In various embodiments, there is a pharmaceutical formulation comprising: a benzodiazepine, wherein the benzodiazepine comprises from about 0.1 wt. % to about 70 wt. % of the formulation, and at least a polyorthoester. In some embodiments, the benzodiazepine comprises from about 1 wt. % to about 50 wt. %, about 5 wt. % to about 50 wt. %, about 5 wt. % to about 40 wt. % or about 10 wt. % to about 35 wt. % of the formulation. In some embodiments, the polyorthoester comprises from about 30 wt. % to about 99.9 wt. %, from about 50 wt. % to about 99 wt. %, from about 50 wt. % to about 95 wt. %, from about 60 wt. % to about 95 wt. %, or from about 65 wt. % to about 90 wt. % of the formulation.
[0105] In various embodiments, the drug is present in the depot in the form of a particle and the particle size is from about 0.1 to 1,000 microns in diameter, however, in various embodiments ranges from about 1 micron to 250 microns, or 5 microns to 50 microns in diameter may be used. In some embodiments, the polyorthoester comprises at least 30 wt. %, at least 40 wt. %, at least 50 wt. %, at least 60 wt. %, at least 70 wt. %, at least 80 wt. % of the formulation, at least 85 wt. % of the formulation, at least 90 wt. % of the formulation, at least 95 wt. % of the formulation or at least 99 wt. % of the formulation. It should be noted that particle size may be altered by techniques such as mortar and pestle, grinding, spray drying, jet-drying or jet milling.
[0106] In some embodiments, at least 75% of the drug particles have a size from about 1 micron to about 200 microns in diameter, more specifically from about 5 microns to about 50 microns in diameter. In some embodiments, at least 85% of the particles have a size from about 1 micron to about 200 microns in diameter, more specifically from about 5 microns to about 50 microns in diameter. In some embodiments, at least 95% of the particles have a size from about 1 micron to about 200 microns in diameter, more specifically from about 5 microns to about 50 microns in diameter. In some embodiments, all of the particles have a size from about 1 micron to about 200 microns in diameter, more specifically from about 5 microns to about 50 microns in diameter.
[0107] In some embodiments, there is a pharmaceutical formulation comprising: a benzodiazepine, and comprises from about 0.1 wt. % to about 70 wt. % of the formulation, and at least a polyorthoester, wherein the polyorthoester comprises at least 30 wt. % of the formulation. In some embodiments, there is a pharmaceutical formulation comprising: a benzodiazepine, wherein a portion of the benzodiazepine is in the form of a salt, such as a hydrochloride salt, and a portion is in the form of a benzodiazepine base, and the mixture comprises about 0.1 wt. % to about 70 wt. % of the formulation, and at least a polyorthoester, wherein the polyorthoester comprises at least 30 wt. % of the formulation.
[0108] In some embodiments, there are methods for treating pain, such as chronic pelvic pain. These methods comprise: administering a pharmaceutical composition to an organism, wherein the pharmaceutical composition comprises from about 0.1 wt. % to about 99 wt. % of the formulation comprising at least a polyorthoester and a benzodiazepine. In some embodiments, the loading is from about 5 wt. % to about 95 wt. %. In some embodiments, the loading is from about 10 wt. % to about 90 wt. %. In some embodiments, the loading is from about 20 wt. % to about 80 wt. %.
[0109] In some embodiments, the formulations are rigid or slightly rigid with varying length, widths, diameters, etc. For example, certain formulations may have a diameter of between about 0.5-3 mm and a length of about 50-100 mm.
[0110] In some embodiments, the benzodiazepine, such as midazolam, is released at a rate of 0.25 mg-10 mg per day for a period of at least thirty days. In some embodiments, this release rate continues for, at least forty days, at least sixty days, at least ninety days, at least one hundred days, at least one-hundred and thirty-five days, at least one-hundred and fifty days, or at least one hundred and eighty days. For some embodiments, 7.5-1,800 milligrams of the benzodiazepine as formulated with a polyorthoester are implanted into a person at or near a target site. It is important to limit the total daily dosage released to an amount less than that which would be harmful to the organism.
[0111] The dosage may be from approximately 0.25 to approximately 10 mg/day. Additional dosages of midazolam include from approximately 0.5 mg/day to approximately 8 mg/day, from approximately 1 mg/day to approximately 8 mg/day, and from approximately 1 mg/day to approximately 5 mg/day.
[0112] In one exemplary dosing regimen, a rat may be provided with sufficient midazolam in a biodegradable POE polymer to provide sustained release of 10 μg/day midazolam for 90 days. The total amount of midazolam that is administered over this time period would be approximately 900 μg. In another exemplary dosing regimen, a human is provided with sufficient midazolam in a biodegradable POE polymer to provide sustained release of 10 mg/day midazolam for 90 days. The total amount of midazolam that is administered over this time period would be approximately 900 mg.
[0113] Having now generally described the invention, the same may be more readily understood through the following reference to the following examples, which are provided by way of illustration and are not intended to limit the present invention unless specified.
EXAMPLES
Example 1
Preparation of Polyorthoester
[0114] A polyorthoester having a molecular weight of 133 kDaltons was synthesized by combining a stoichiometric mixture of 3,9-diethylidene-2,4,8,10-tetraoxospiro[5,5]undecane (DETOSU) with a mixture of diols including trans-1,4-cyclohexanedimethanol (54 mole %), 1,6-hexanediol (45 mole %) and diethyl-tartrate (1 mole %). Midazolam was purchased from Orgamol (Switzerland). Methanol and acetone were purchased from Sigma-Aldrich.
[0115] Methods: The following compositions were used to prepare a polyothoester: DETOSU at 34.9998 g (164.90 mmole), Trans-cyclohexanedimethanol at 12.5898 g (87.30 mmole), 1,6-hexanediol at 8.5965 g (72.75 mmole), Diethyltartrate at 0.3333 g (1.62 mmole), Para-toluenesulfonicacid at 2325 μl of a 1% (w/v) solution in tetrahydrofuran (THF) and 315 ml of Tetrahydrofuran. In particular, a 1000 ml round bottomed flask was pyro-cleaned, washed with soap and water, then rinsed with acetone, isopropanol, 0.1N NaOH and deionized water, and then oven-dried. All spatulas to be used for preparing the polymer were washed and dried in the oven for at least 2 hours. A small glass beaker was also washed and dried in the oven. All of the reactants were weighed in a beaker. In a N 2 glove box, DETOSU was first weighed into the beaker followed by the diols. 200 ml of THF was then added to dissolve the solids and this solution was poured into the round bottomed flask. The rest of the THF was then added to the beaker again and then into the flask. The solution was allowed to stir for 30 minutes. A 1% PTSA catalyst was then added to the solution at which point the solution exothermed vigorously and became very thick. The stirring was then stopped and the solution remained in the flask overnight. An IR scan of a sample of the polymer solution was taken the next day and it showed that the polymerizaion was complete (there was a minor peak at 3501 cm −1 but that was due to the thickness of the sample on the IR plate).
[0116] A blender was washed and dried in the oven for at least 8 hours. A tweezer was also dried. In the N 2 glove box, ˜500 ml of anhydrous methanol was added to the blender. Four (4) drops of triethylanine were then added to the waring blender. The polymer solution was then slowly poured into a methanol solution. The polymer precipitated out easily. The precipitated polymer was then redissolved in minimal THF and poured in fresh methanol. The polymer precipitated again and was then put in a mylar boat and dried in the vacuum oven at fill vacuum and 50° C. for two days. The POE polymer was then transferred to a dried jar.
Example 2
Preparation of POE-Midazolam Microspheres
[0117] In some embodiments it may be desirable to make drug depots in the form of microspheres. This can be accomplished using methods and apparatus known to those of skill in the art and described herein.
[0118] For example, microspheres are prepared using a water/oil emulsion with a vacuum-controlled hardening step. 850 mg of the polymer from Example 1, polyorthoester (54 mole % trans-cylcohexanedimethanol, 45% 1,6-hexanediol and 1% diethyltartrate) is dissolved in methylene chloride along with midazolam (150-mg) at a solids concentration of 1-g per 12-ml. The solution is then filtered through a 0.2 μm PTFE syringe filter. The polymer/drug solution, 12-ml, is added slowly over 1 minute into a 120-ml jar containing 60-ml of a 10 mM Trizma® base buffer at pH 8.5 with 1% (w/v) polyvinylalcohol (Sigma-Aldrich) while being mixed at 6,000 rpm with an IKA Ultra-Turrax T-18 high-shear mixer. The solution is mixed for 2 minutes and then poured into a 250-ml round bottom flask, followed by 20-ml of water used to rinse the jar. The flask is immediately placed on a rotoevaporator and the pressure is reduced from 700 mbar to 5 mbar over 45 minutes and held at 5 mbar for 15 minutes. The hardened microsphere suspension is poured into two 50-ml conical tubes and centrifuged at 1000 rpm for 2 minutes. The supernatant is poured off and the spheres from each tube are transferred to a single 50-ml conical tube and rinsed with 45-ml of water, centrifuged again, and the supernatant is poured off. This is repeated 2 more times and the spheres are then resuspended in 7-ml of water and frozen in liquid nitrogen. The frozen suspension is lyophilized for 24 hours and then transferred to a vacuum oven at 25° C. and dried for 1 week. The microspheres mean particle size is measured with a Horiba LA-950 particle size analyzer.
Example 3
In-vitro Release of Midazolam
[0119] Drug elution of midazolam from the microspheres described in Example 2 is measured using a pouch method. The pouch method involves adding 15-mg of the spheres described in Example 2 to a ¾″ by ¾″ nylon pouch with a 5-micron mesh size. The pouch is prepared by heating sealing 3 sides of the nylon mesh, adding the spheres, and then heat sealing the final side of the pouch. The pouch is placed in 10-ml of phosphate buffered saline pH 7.4 contained in a vial and placed in an incubator/shaker at 37° C. and 100 RPM. Sampling is performed by removing 8-ml of media with a pipette and then adding 8-ml of fresh media to the vial. The samples are then returned to the incubator/shaker. Sampling is performed daily for the first week and then once per week for 180 days. Drug concentrations in the elution media are measured by HPLC with UV detection.
Example 4
Preparation of Spray Dried Midazolam
[0120] In some embodiments, the midazolam is formulated with the POE as a particle. It may be desired to have the particles within a desired size range. This can be accomplished by dissolving the midazolam in an appropriate solvent and spray drying the solution using methods and apparatus known to those of skill in the art and described herein.
[0121] For example, midazolam is dissolved in methylene chloride to yield a solution. The solution is spray dried in a Buchi B-290 Mini Spray Dryer (Buchi Laboratorium AG, Switzerland) using a 120 kHz Sono-Tek ultrasonic nozzle (Sono-Tek Corp., Milton, N.Y.). Exemplary processing parameters include: inlet temp. (40° C.), aspirator (80%), nitrogen inlet (50 mm), spray flow rate (80 mL/hr) and ultrasonic generator (0.8 watts). The spray dried powder is collected and dried, such as for an additional 24 hours at 70° C. and 15 mmHg vacuum.
Example 5
Preparation of Melt Extruded Rods
[0122] In some embodiments, the midazolam is melt extruded with the POE. This can be accomplished by using methods and apparatus known to those of skill in the art and described herein.
[0123] For example, several formulations having midazolam drug loadings of 5% (w/w), 10% (w/w), 20% (w/w), 30% (w/w), 40% (w/w) and 50% (w/w) are prepared for melt extrusion with POE described in Example 1. Each formulation contains POE polymer ground into powder using a Retsch (Retsch GmbH, Germany) rotor mill with an 80 micrometer sieve filter and spray dried midazolam as described in Example 4. All formulations are dry mixed with a spatula prior to being fed into a Haake Mini-Lab twin screw extruder (Thermo Fischer Scientific, Waltham, Mass.) set at 120° C. and 30 RPM. The rods are extruded out of a 0.75 mm diameter die and pulled by hand to obtain a final diameter of ˜0.7-0.8 mm.
[0124] The rods are then cut with a razor blade to desired length depending on the corresponding drug loadings. Pellets from each formulation are placed in 20 mL scintillation vials for drug elution testing. In-vitro elution studies are carried out at 37° C. in phosphate-buffered saline (PBS, pH 7.4). In particular, the pellets are incubated in 5 mL of phosphate buffered saline pH 7.4 (Hyclone, 0.0067M) at 37° C. under mild agitation. At pre-selected times over a 135 day period, the buffer is removed for analysis and replaced with fresh buffer medium. The drug content is quantified at 220 nm by a Molecular Devices SpectraMax M2 (Sunnyvale, Calif.) plate reader.
Example 6
Preparation of Spray Dried POE-Midazolam Microparticles
[0125] In some embodiments, the midazolam and POE are spray dried together to form microparticles. This can be accomplished using methods and apparatus known to those of skill in the art and described herein.
[0126] For example, midazolam and POE are dissolved together in methylene chloride to yield a solution. The solution is spray dried in a Buchi B-290 Mini Spray Dryer (Buchi Laboratorium AG, Switzerland) using a 120 kHz Sono-Tek ultrasonic nozzle (Sono-Tek Corp., Milton, N.Y.). Exemplary processing parameters include: inlet temp. (40° C.), aspirator (80%), nitrogen inlet (50 mm), spray flow rate (80 mL/hr) and ultrasonic generator (0.8 watts). The spray dried powder is collected and dried, such as for an additional 24 hours at 70° C. and 15 mmHg vacuum.
Example 7
Epidural Administration of POE-Midazolam Depot in a Rat Model of Bladder Pain
[0127] In some embodiments, the drug depot is implanted in a mammal. This can be accomplished by using methods and apparatus known to those of skill in the art and described herein.
[0128] For example, an animal model that has been used frequently to study pelvic pain conditions is a rat model of bladder pain. In this model, a female rat is lightly anesthetized with isoflurane and a transurethral catheter is placed into the bladder. The catheter is connected to a pressure transducer so that the pressure within the bladder can be continuously monitored and recorded over time. Fluid is continuously infused into the bladder using a syringe pump at a rate of 0.1 mL/min to cause the bladder to contract repeatedly each time it become fill. This is referred to as a volume-evoked micturition reflex or contraction. A repeated series of bladder contractions (pressure spikes) over time is collected using this method. To mimic normal bladder activity, 0.9% saline is infused into the bladder; to mimic painful bladder activity, a dilute solution of acetic acid (0.5%) is infused into the bladder. Acetic acid infusion produces a marked increase in the frequency of bladder contractions. In human patients that suffer from interstitial cystitis, a common form of pelvic pain, increased frequency of urination and urinary urgency are common clinical symptoms.
[0129] In order to evaluate the effects of epidurally administered drugs on normal and painful bladder activity (frequency of reflex bladder contractions), midazolam is continuously administered via an epidural drug depot.
[0130] For example, a drug depot designed to deliver 10 μg/day of midazolam is epidurally administered to the mid-lumbar epidural space. The baseline bladder activity is measured before implanting the epidural drug depot, the drug depot system is implanted on day 0 and cystometrograms are recorded periodically over 135 days during which midazolam (25 μg/day) is released into the lumbar epidural space.
[0131] It will be apparent to those skilled in the art that various modifications and variations can be made to various embodiments described herein without departing from the spirit or scope of the teachings herein. Thus, it is intended that various embodiments cover other modifications and variations of various embodiments within the scope of the present teachings. | Effective treatments of pain for extended periods of time are provided. The treatments include the administration of one or more drug depots intraspinally wherein the drug depots include an effective amount of a benzodiazepine, such as midazolam, formulated within a polyorthoester. By administration of one or more drug depots, one can relieve pain caused by diverse sources, including but not limited to chronic pelvic pain syndromes, spinal disc herniation (i.e. sciatica), spondilothesis, stenosis, discongenic back pain and joint pain, as well as pain that is incidental to surgery. In some embodiments, the relief can be for at least twenty-five days, at least fifty days, at least one hundred days or at least one hundred and thirty-five days. | 0 |
RELATED APPLICATION
This application is a divisional of Ser. No. 153,854 filed Nov. 18, 1993, now U.S. Pat No. 5,525,723.
BACKGROUND OF THE INVENTION
Captopril, (S)-1-(3-mercapto-2-methyl-1-oxopropyl)-L-proline, having the structural formula ##STR2## is an orally active angiotensin converting enzyme inhibitor useful for treating hypertension and congestive heart failue. See Ondetti et al. U.S. Pat. No. 4,105,776.
Enalapril, (S)-1-[N-[1-(ethoxycarbonyl)-3-phenylpropyl]-L-alanyl]-L-proline, having the structural formula ##STR3## is also an orally active angiotensin converting enzyme inhibitor. Enalapril contains the L-alanyl-L-proline dipeptide. A related compound, lisinopril, also possesses oral angiotensin converting enzyme inhibitor activity and contains the L-lysyl-L-proline dipeptide. See Harris et al. U.S. Pat. No. 4,374,829.
Fosinopril sodium, (4S) -4-cyclohexyl-1-[[(R)-[(S)-1-hydroxy-2-methylpropoxy](4-phenylbutyl)-phosphinyl]acetyl]-L-proline propionate (ester), sodium salt having the structural formula ##STR4## is also an orally active angiotensin converting enzyme inhibitor useful for treating hypertension. See Petrillo U.S. Pat. No. 4,337,201.
Haslanger et al. in U.S. Pat. No. 4,749,688 disclose treating hypertension by administering neutral metalloendopeptidase inhibitors alone or in combination with atrial peptides or angiotensin converting enzyme inhibitors.
Neustadt in U.S. Pat. No. 5,075,302 disclose that mercaptoacyl amino lactams of the formula ##STR5## wherein Y includes propylene and butylene, R 1 is lower alkyl, aryl or heteroaryl, and R 2 is hydrogen, lower alkyl, lower alkoxy lower alkyl, aryl-lower alkyl or heteroaryl-lower alkyl are endopeptidase inhibitors. Neustadt disclose employing such compounds alone or in combination with angiotensin converting enzyme inhibitors to treat cardiovascular diseases such as hypertension, congestive heart failure, edema, and renal insufficiency.
Delaney et al. U.K. Patent 2,207,351 disclose that endopeptidase inhibitors produce diuresis and natriuresis and are useful alone or in combination with angiotensin converting enzyme inhibitors for the reduction of blood pressure. Delaney et al. include various mercapto and acylmercapto amino acids and dipeptides among their endopeptidase inhibiting compounds.
Flynn et al. in European Patent Application 481,522 disclose dual inhibitors of enkephalinase and angiotensin converting enzyme of the formulas ##STR6## wherein n is zero or one and Z is O, S, --NR 6 -- or ##STR7## Additional tricyclic dual inhibitors are disclosed by Warshawsky et al. in European Patent Applications 534,363, 534,396 and 534,492.
Karanewsky et al. in U.S. Pat. Nos 4,432,971 and 4,432,972 disclose phosphonamidate angiotensin converting enzyme inhibitors of the formula ##STR8## wherein X is a substituted imino or amino acid or ester.
Karanewsky in U.S. Pat. No. 4,460,579 discloses angiotensin converting enzyme inhibitors including those of the formula ##STR9## and in U.S. Pat. No. 4,711,884 discloses angiotensin converting enzyme inhibitors including those of the formula ##STR10## wherein x is a thiazine or thiazepine.
Ruyle in U.S. Pat. No. 4,584,294 disclose angiotensin converting enzyme inhibitors of the formula ##STR11##
Parsons et al. in U.S. Pat. No. 4,873,235 disclose angiotensin converting enzyme inhibitors of the formula ##STR12##
SUMMARY OF THE INVENTION
This invention is directed to novel compounds containing a fused multiple ring lactam which are useful as angiotensin converting enzyme inhibitors. Some of these compounds also possess neutral endopeptidase inhibitory activity. This invention is also directed to pharmaceutical compositions containing such selective or dual action inhibitors and the method of using such compositions. This invention is also directed to the process for preparing such novel compounds and novel intermediates.
The novel fused multiple ring lactam compounds of this invention include those compounds of the formula ##STR13## and pharmaceutically acceptable salts thereof wherein: ##STR14## R 1 and R 12 are independently selected from hydrogen, alkyl, alkenyl, cycloalkyl, substituted alkyl, substituted alkenyl, aryl, substituted aryl, heteroaryl, cycloalkyl-alkylene-, aryl-alkylene-, substituted aryl-alkylene-, and heteroaryl-alkylene- or R 1 and R 12 taken together with the carbon to which they are attached complete a cycloalkyl ring or a benzofused cycloalkyl ring;
R 2 is hydrogen, ##STR15## or R 11 --S--; R 3 , R 5 and R 7 are independently selected from hydrogen, alkyl, substituted alkyl, aryl-(CH 2 ) p -, substituted aryl-(CH 2 ) p -, heteroaryl-(CH 2 ) p -, ##STR16## R 4 is alkyl, cycloalkyl-(CH 2 ) p -, substituted alkyl, aryl-(CH 2 ) p -, substituted aryl-(CH 2 ) p -, or heteroaryl-(CH 2 ) p -;
R 6 is alkyl, substituted alkyl, cycloalkyl-(CH 2 ) p -, aryl-(CH 2 ) p -, substituted aryl-(CH 2 ) p -, or heteroaryl-(CH 2 ) p -;
R 8 is hydrogen, lower alkyl, cycloalkyl, or phenyl;
R 9 is hydrogen, lower alkyl, lower alkoxy, or phenyl;
R 10 is lower alkyl or aryl-(CH 2 ) p -;
R 11 is alkyl, substituted alkyl, cycloalkyl(CH 2 ) p -, aryl-(CH 2 ) p -, substituted aryl-(CH 2 ) p -, heteroaryl-(CH 2 ) p -, or --S--R 11 completes a symmetrical disulfide wherein R 11 is ##STR17## m is one or two; n is zero or one;
q is zero or an integer from 1 to 3;
p is zero or an integer from 1 to 6; ##STR18## represents an aromatic heteroatom containing ring selected from ##STR19## X 1 is S or NH; X 2 is S, O, or NH; and
R 13 is hydrogen, lower alkyl, lower alkoxy, lower alkylthio, chloro, bromo, fluoro, trifluoromethyl, amino, --NH(lower alkyl), --N(lower alkyl) 2 , or hydroxy.
DETAILED DESCRIPTION OF THE INVENTION
The term "alkyl" refers to straight or branched chain radicals having up to seven carbon atoms. The term "lower alkyl" refers to straight or branched radicals having up to four carbon atoms and is a preferred subgrouping for the term alkyl.
The term "substituted alkyl" refers to such straight or branched chain radicals of 1 to 7 carbons wherein one or more, preferably one, two, or three, hydrogens have been replaced by a hydroxy, amino, cyano, halo, trifluoromethyl, --NH(lower alkyl), --N(lower alkyl) 2 , lower alkoxy, lower alkylthio, or carboxy.
The term "halo" refers to chloro, bromo, fluoro, or iodo.
The terms "lower alkoxy" and "lower alkylthio" refer to such lower alkyl groups as defined above attached to an oxygen or sulfur.
The term "cycloalkyl" refers to saturated rings of 3 to 7 carbon atoms with cyclopentyl and cyclohexyl being most preferred.
The term "alkenyl" refers to straight or branched chain radicals of 3 to 7 carbon atoms having one or two double bonds. Preferred "alkenyl" groups are straight chain radicals of 3 to 5 carbons having one double bond.
The term "substituted alkenyl" refers to such straight or branched radicals of 3 to 7 carbons having one or two double bonds wherein a hydrogen has been replaced by a hydroxy, amino, halo, trifluoromethyl, cyano, --NH(lower alkyl), --N(lower alkyl) 2 , lower alkoxy, lower alkylthio, or carboxy.
The term "alkylene" refers to straight or branched chain radicals having up to seven carbon atoms, i.e. --CH 2 --, --(CH 2 ) 2 --, --(CH 2 ) 3 --, --(CH 2 ) 4 --, ##STR20## etc.
The term "aryl" refers to phenyl, 1-naphthyl, and 2-naphthyl. The term "substituted aryl" refers to phenyl, 1-naphthyl, and 2-naphthyl having a substituent selected from lower alkyl, lower alkoxy, lower alkylthio, halo, hydromy, trifluoromethyl, amino, --NH(lower alkyl), or --N(lower alkyl) 2 , and di- and tri-substituted phenyl, 1-naphthyl, or 2-naphthyl wherein said substituents are selected from methyl, methoxy, methylthio, halo, hydroxy, and amino.
The term "heteroaryl" refers to unsaturated rings of 5 or 6 atoms containing one or two O and S atoms and/or one to four N atoms provided that the total number of hetero atoms in the ring is 4 or less. The heteroaryl ring is attached by way of an available carbon or nitrogen atom. Preferred heteroaryl groups include 2-, 3-, or 4-pyridyl, 4-imidazolyl, 4-thiazolyl, 2- and 3-thienyl, and 2- and 3-furyl. The term heteroaryl also includes bicyclic rings wherein the five or six membered ring containing O, S, and N atoms as defined above is fused to a benzene or pyridyl ring. Preferred bicyclic rings are 2- and 3-indolyl and 4- and 5-quinolinyl. The mono or bicyclic heteroaryl ring can also be additionally substituted at an available carbon atom by a lower alkyl, halo, hydroxy, benzyl, or cyclohexylmethyl. Also, if the mono or bicyclic ring has an available N-atom such N atom can also be substituted by an N-protecting group such as ##STR21## 2,4-dinitrophenyl, lower alkyl, benzyl, or benzhydryl.
The compounds of formula I wherein ##STR22## can be prepared by coupling the acylmercapto containing sidechain of the formula ##STR23## with a fused multiple ring lactam of the formula ##STR24## to give the product of formula ##STR25## wherein R 3 is an easily removable ester protecting group such as methyl, ethyl, t-butyl, or benzyl. The above reaction can be performed in an organic solvent such as methylene chloride and in the presence of a coupling reagent such as 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, dicylcohexylcarbodiimide, benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate, or carbonyldiimidazole. Alternatively, the acylmercapto carboxylic acid of formula II can be converted to an activated form prior to coupling such as an acid chloride, mixed anhydride, symmetrical anhydride, activated ester, etc.
The product of formula IV can be converted to the mercaptan product of formula I wherein R 2 is hydrogen and R 3 is hydrogen by methods known in the art. For example, when R 6 is methyl and R 3 is methyl or ethyl treatment with methanolic sodium hydroxide yields the products wherein R 2 and R 3 are hydrogen.
The products of formula I wherein R 2 is hydrogen can be acylated with an acyl halide of the formula ##STR26## wherein halo is F, Cl or Br or acylated with an anhydride of the formula ##STR27## to give other products of formula I wherein R 2 is ##STR28##
The products of formula I wherein R 2 is --S--R 11 and R 11 is alkyl, substituted alkyl, cycloalkyl-(CH 2 ) p -, aryl-(CH 2 ) p -, substituted aryl-(CH 2 ) p -, or heteroaryl-(CH 2 ) p - can be prepared by reacting the products of formula I wherein R 2 is hydrogen with a sulfonyl compound of the formula
H.sub.3 C--SO.sub.2 --S--R.sub.11 (VII)
in an aqueous alcohol solvent to yield the desired products. The compounds of formula VII are known in the literature or can be prepared by known methods, see for example, Smith et al., Biochemistry, 14, p 766-771 (1975).
The symmetrical disulfide products of formula I can be prepared by direct oxidation of the product of formula I wherein R 2 is hydrogen with iodine as note, for example, Ondetti et al. U.S. Pat. No. 4,105,776.
The acylmercapto sidechain compounds of formula II wherein R 12 is hydrogen are described in the literature. See, for example, Ondetti et al. U.S. Pat. Nos. 4,105,776 and 4,339,600, Haslanger et al. U.S. Pat. No. 4,801,609, Delaney at al. U.S. Pat. No. 4,722,810, etc.
The acylmercapto sidechain compounds of formula II wherein R 1 and R 12 are both other than hydrogen and n is zero can be prepared by reacting the substituted carboxylic acid of the formula ##STR29## with bis[(4-methoxy)phenyl]methyldisulfide in the presence of lithium diisopropylamide to give the compound of the formula ##STR30## Treatment of the compound of formula IX with strong acid such as trifluoromethanesulfonic acid removes the methoxybenzyl protecting group and is followed by acylation with the acyl halide of formula V or anhydride of formula VI to give the compound of formula II wherein R 1 and R 12 are both other than hydrogen and n is zero.
The acylmercapto sidechain compounds of formula II wherein R 1 and R 12 are both other than hydrogen and n is one can be prepared by reacting the substituted carboxylic acid of the formula ##STR31## with para-toluenesulfonyl chloride in pyridine to give the lactone of the formula ##STR32## Treatment of the lactone of formula XI with a cesium thioacid of the formula ##STR33## in the presence of dimethylformamide yields the desired acylmercapto sidechain of formula II wherein R 1 and R 12 are both other than hydrogen and n is one.
The compounds of formula I wherein A is ##STR34## can be prepared by coupling the acid of the formula ##STR35## wherein R 7 is an ester protecting group with the fused multiple ring lactam of formula III in the presence of a coupling reagent as defined above to give the product of the formula ##STR36## Alternatively, the acid of formula XIII can be converted to an activated form such as an acid chloride prior to the coupling reaction.
The acids of formula XIII are described by Warshawsky et al. in European Patent Application 534,396 and 534,492.
The compounds of formula I wherein A is ##STR37## can be prepared by reacting a keto acid or ester of the formula ##STR38## with fused multiple ring lactam of formula III under reducing conditions to give the product of the formula ##STR39##
The keto acids and esters of formula XV are described in the literature. See, for example, Ruyle U.S. Pat. No. 4,584,294 and Parsons et al. U.S. Pat. No. 4,873,235.
Alternatively, the fused multiple ring lactam compound formula III can be reacted with a triflate of the formula ##STR40## to give the product of formula XVI.
The compounds of formula I wherein A is ##STR41## can be prepared by coupling a phosphonochloridate of the formula ##STR42## wherein R 5 is lower alkyl or benzyl with a fused multiple ring lactam of formula III to give the product of the formula ##STR43## Preferably, the compound of formula III is in its hydrochloride salt form and R 3 is lower alkyl or benzyl. The R 3 and R 5 ester protecting groups can be removed, for example, by hydrogenation to give the corresponding products of formula I wherein R 3 and R 5 are hydrogen.
The phosphonochloridates of formula XVIII are known in the literature. See, for example, Karanewsky et al. U.S. Pat. Nos 4,432,971 and 4,432,972 and Karanewsky U.S. Pat. No. 4,460,579.
The ester products of formula I wherein R 5 or R 7 is ##STR44## can be prepared by treating the corresponding compounds of formula I wherein R 5 or R 7 is hydrogen and R 3 is an ester protecting group with a compound of the formula ##STR45## wherein L is a leaving group such as chloro, bromo, or tolylsulfonyloxy followed by removal of the R 3 ester protecting group.
The ester products of formula I wherein R 3 is ##STR46## can be prepared by treating the corresponding compounds of formula I wherein R 3 is hydrogen and R 2 is ##STR47## with a compound of formula XX.
The fused multiple ring lactams of formula III can be prepared according to the following process which also forms part of thia invention. An N-protected carboxylic acid of the formula ##STR48## can be coupled with the amino acid ester of the formula ##STR49## to give the compound of the formula ##STR50## This reaction can be performed in the presence of a coupling reagent as defined above.
The alcohol of formula XXIII can be converted to the corresponding aldehyde such as by treatment with 4-methylmorpholine N-oxide and tetrapropyl ammonium perruthenate or treatment with oxalyl chloride, dimethylsulfoxide, and triethylamine. This aldehyde can then be cyclized by treatment with a strong acid such as trifluoroacetic acid or trifluoroacetic acid followed by trifluoromethanesulfonic acid to give the compound of the formula ##STR51##
Alternatively, the N-protected carboxylic acid of the formula XXI can be coupled with the amino acid ester of the formula ##STR52## to give the compound of the formula ##STR53##
The compound of formula XXVI can be cyclized by treatment with strong acid such as trifluoroacetic acid or trifluoroacetic acid followed by trifluoromethanesulfonic acid to give the compound of formula XXIV.
Treatment of compound XXIV with hydrazine monohydrate removes the N-phthalimido protecting group and gives the fused multiple ring lactam of formula III.
The compounds of formula I contain three asymmetric centers in the fused multiple ring lactam portion of the structure with an additional center possible in the side chain. While the optically pure form of the fused multiple ring lactam described above is preferred, all such forms are within the scope of this invention. The above described processes can utilize racemates, enantiomers, or diastereomers as starting materials. When diastereomeric compounds are prepared, they can be separated by conventional chromatographic or fractional crystallization methods. Preferably, the hydrogen attached to the bridgehead carbon is in the orientation shown below ##STR54##
The compounds of formula I wherein R 3 , R 5 and/or R 7 are hydrogen can be isolated in the form of a pharmaceutically acceptable salt. Suitable salts for this purpose are alkali metal salts such as sodium and potassium, alkaline earth metal salts such as calcium and magnesium, and salts derived from amino acids such as arginine, lysine, etc. These salts are obtained by reacting the acid form of the compound with an equivalent of base supplying the desired ion in a medium in which the salt precipitates or in aqueous medium and then lyophilizing.
Preferred compounds of this invention are those wherein:
A is ##STR55## R 2 is hydrogen, ##STR56## or R 11 --S--; R 3 is hydrogen or lower alkyl of 1 to 4 carbons;
n is zero or one;
R 12 is hydrogen;
R 11 is lower alkyl of 1 to 4 carbons;
R 1 is aryl-CH 2 --, substituted aryl-CH 2 --, heteroaryl-CH 2 --, cycloalkyl-CH 2 -- wherein the cycloalkyl is of 5 to 7 carbons, or straight or branched chain alkyl of 1 to 7 carbons;
R 6 is lower alkyl of 1 to 4 carbons or phenyl;
m is one or two; and ##STR57##
Most preferred are the above compounds wherein:
R 2 is hydrogen or ##STR58## especially hydrogen; R 3 is hydrogen;
n is zero;
R 1 is benzyl; and
m is two.
The compounds of formula I wherein A is ##STR59## are dual inhibitors possessing the ability to inhibit angiotensin converting enzyme and neutral endopeptidase. The compounds of formula I wherein A is ##STR60## are selective inhibitors possessing the ability to inhibit the angiotensin converting enzyme. Thus, all of the compounds of formula I including their pharmaceutically acceptable salts are useful in the treatment of physiological conditions in which angiotensin converting enzyme inhibitors have been shown to be useful. Such conditions include disease states characterized by abnormalities in blood pressure, intraocular pressure, and renin including cardiovascular diseases particularly hypertension and congestive heart failure, glaucoma, and renal diseases such as renal failure. The dual inhibitors are also useful in the treatment of physiological conditions in which neutral endopeptidase inhibitors have been shown to be useful. Such conditions also include cardiovascular diseases particularly hypertension, hyperaldosteronemia, renal diseases, glaucoma, as well as the relief of acute or chronic pain. Thus, the compounds of formula I are useful in reducing blood pressure and the dual inhibitors of formula I are additionally useful for this purpose due to their diuresis and natriuresis properties. The compounds of formula I including their pharmaceutically acceptable salts can be administered for these effects to a mammalian host such as man at from about 1 mg. to about 100 mg. per kg. of body weight per day, preferably from about 1 mg. to about 50 mg. per kg. of body weight per day. The compounds of formula I are preferably administered orally but parenteral routes such as subcutaneous, intramuscular, and intravenous can also be employed as can topical routes of administration. The daily dose can be administered singly or can be divided into two to four doses administered throughout the day.
The inhibitors of formula I can be administered in combination with human ANF 99-126. Such combination would contain the inhibitor of formula I at from about 1 to about 100 mg. per kg. of body weight and the human ANF 99-126 at from about 0.001 to about 0.1 mg. per kg. of body weight.
The inhibitors of formula I can be administered in combination with other classes of pharmaceutically active compounds. For example, a calcium channel blocker, a potassium channel activator, a cholesterol reducing agent, etc.
The inhibitors of formula I or a pharmaceutically acceptable salt thereof and other pharmaceutically acceptable ingredients can be formulated for the above described pharmacetical uses. Suitable compositions for oral administration include tablets, capsules, and elixirs, and suitable compositions for parenteral administration include sterile solutions and suspensions. Suitable compositions for treating glaucoma also include topical compositions such as solutions, ointments, and solid inserts as described in U.S. Pat. No. 4,442,089. About 10 to 500 mg. of active ingredient is compounded with physiologically acceptable vehicle, carrier, excipient, binder, preservative, stabilizer, flavoring, etc., in a unit dose form as called for by accepted pharmaceutical practice.
The following examples are illustrative of the invention. Temperatures are given in degrees centigrade. Thin layer chromatography (TLC) was performed in silica gel unless otherwise stated.
EXAMPLE 1
[4S-[4α,7α(R*),13bβ]]-1,3,4,6,7,8,13,13b-Octahydro-6-oxo-7-[(2-mercapto-1-oxo-3-phenylpropyl)amino]-2H-pyrido[1',2':1,2]azepino[3,4-b]indole-4-carboxylic acid
a) N-Phthalimido-L-tryptophan,dicyclohexylamine salt
A slurry of L-tryptophan (15.0 g., 73.4 mmol.) and sodium carbonate (7.785 g, 73.4 mmol.) in water (200 ml.) was stirred at room temperature for 15 minutes, then treated with N-carbethoxyphthalimide (16.098 g., 73.4 mmol.). The non-homogeneous solution became yellow immediately. After stirring for 2 hours, the clear yellow solution was cooled to 0° C. and acidified with 6 N hydrochloric acid. The resulting solid was collected by filtration and washed with water. The solid was dissolved in ethyl acetate and washed with water and brine, then dried (sodium sulfate), filtered and stripped to give a yellow oil/foam. The foam was flash chromatographed (Merck silica gel, 5% acetic acid in ethyl acetate) to give the slighly impure desired free acid as a yellow oil. The oil was dissolved in ethyl acetate/ethyl ether and treated with dicyclohexylamine (14.5 ml.) to give pure title compound as a yellow powder (18.955 g.); m.p. 145°-148° (decomp.) TLC: (5% acetic acid in ethyl acetate) R f =0.57.
b) N-(N-Phthalimido-L-tryptophyl)-6-hydroxy-L-norleucine, methyl ester
Hydrogen chloride gas was bubbled in a slurry of 6-hydroxy-L-norleucine [prepared as described by Bodanszky et al., J. Med. Chem., 21, p. 1030-1035 (1978), 1.00 g., 6.9 mmol.] in dry methanol (35 ml.) until the mixture became homogeneous and began to reflux. The solution was then let cool and was stirred at room temperature for 2.5 hours. The methanol was removed by rotary evaporation and the residue was azeotroped twice with toluene to give crude 6-hydroxy-L-norleucine, methyl ester hydrochloride as a gum. Meanwhile, the dicyclohexylamine salt product from part (a) (3.506 g., 6.8 mmol.) was partitioned between 5% potassium bisulfate and ethyl acetate. The ethyl acetate extract was washed with additional 5% potassium bisulfate and brine, then dried (sodium sulfate), filtered and stripped to give N-phthalimido-L-tryptophan as the free acid.
The above crude 6-hydroxy-L-norleucine, methyl ester, hydrochloride was dissolved in dimethylformamide (6 ml.) and methylene chloride (25 ml.) and treated with 4-methylmorpholine (1.30 ml., 1.20 g., 11.8 mmol.). The solution was cooled to 0° C. and treated with N-phthalimido-L-tryptophan followed by hydroxybenzotriazole (925 mg., 6.8 mmol.) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.438 g., 7.5 mmol.). The mixture was stirred at 0° C. for 0.5 hour and then at room temperature for 2.5 hours. The solution was partitioned between ethyl acetate and water and the organic layer was washed successively with 0.5 N hydrochloric acid, water, 5% sodium bicarbonate, and brine, then dried (sodium sulfate), filtered and stripped to give 3.06 g., of title product as a yellow foam. TLC: (ethyl acetate) R f =0.35.
c) N-(N-Phthalimido-L-tryptophyl)-6-oxo-L-norleucine, methyl ester
To a pre-dried (magnesium sulfate) solution of 4-methylmorpholine N-oxide (760 mg., 6.5 mmol.) in methylene chloride (90 ml.) was added the product from part (b) (2.065 g., 4.3 mmol.), dry 4 A molecular sieves (10 g.) and tetrapropyl ammoniumperruthenate (85 mg.). The mixture was stirred at room temperature and was charged with additional tetrapropyl ammoniumperruthenate (35 mg.) after 1, 2, and 3 hours of stirring. After 3.5 hours, the dark mixture was diluted with ethyl acetate and filtered through a short plug of Merck silica gel. The filtrate was stripped and the residue was flash chromatographed (Merck silica gel, 20:80-hexanes:ethyl acetate) to give 1.160 g., of title product as a yellow foam. TLC (ethyl acetate) R f =0.49.
d) [4S-[4α,7α,13bα]]-1,3,4,6,7,8,13,13b-Octahydro-6-oxo-7-phthalimido-2H-pyrido[1',2':1,2]azepino[3,4-b]indole-4-carboxylic acid, methyl ester
A solution of the product from part (c) (990 mg., 2.08 mmol.) was gently refluxed in a solution of methylene chloride (26 ml.) and trifluoroacetic acid (240 μl) for 3.5 hours. The cooled solution was washed with saturated sodium bicarbonate, dried (sodium sulfate), filtered and stripped. The residue was flash chromatographed (Merck silica gel, 12% ethyl acetate in methylene chloride) to give a solid. Recrystallization from ethyl ether/methylene chloride afforded 499 mg. of the desired product as a crystalline light yellow solid; m.p. 185° C. (decomp.); [α] D =-117.2° (c=0.8, chloroform). TLC (20% ethyl acetate in methylene chloride) R f =0.39.
e) [4S-[4α,7α,13b,βB]]-1,3,4,6,7,8,13,13b-Octahydro-7-amino-6-oxo-2H-pyrido[1',2':1,2]azepino[3,4-b]indole-4-carboxylic acid, methyl ester
A slurry of the product from part (d) (570 mg., 1.24 mmol.) in methanol (5 ml.) was treated with hydrazine monohydrate (133 μl., 129 mg., 2.6 mmol.). Slight heating was neccessary to effect a homogeneous solution. After stirring at room temperature for 15 hours, the mixture (thick with precipitate) was stirred with 16 ml. of 0.5 N hydrochloric acid at 0° C. for 2.5 hours. The solution was filtered and the solid was washed with water. The filtrate was washed with ethyl acetate, made basic with 1 N sodium hydroxide and subsequently extracted twice with methylene chloride. The pooled methylene chloride extracts were dried (sodium sulfate), filtered and stripped to afford the product as a solid (145 mg.). The original aqueous insoluble precipitate was partially dissolved in methanol and partitioned with vigorous shaking between ethyl acetate and 0.5 N hydrochloric acid. The aqueous layer was separated and made basic with 2 N sodium hydroxide and subsequently extracted twice with methylene chloride. The pooled methylene chloride extracts were dried (sodium sulfate), filtered and stripped to give additional desired product (approximately 200 mg.). The isolated solids were pooled, taken up in methylene chloride, concentrated and triturated with ethyl ether to give 319 mg. of title compound as a white solid; m.p. 204°-206° C. (decomp.). [α] D =-30.3° (c=0.5, chloroform). TLC (8:1:1, methylene chloride:acetic acid:methanol) R f =0.35.
) (S)-2-(Acetylthio)benzenepropanoic acid, dicyclohexylamine salt
Sodium nitrite (10.3 g., 280 mmol.) was added to a solution of D-phenylalanine (30.0 g., 181 mmol.) and potassium bromide (73.5 g.) in sulfuric acid (2.5 N, 365 ml.) over a period of one hour while maintaining the temperature of the reaction mixture at 0° C. The mixture was stirred for an additional hour at 0° C. and then for one hour at room temperature. The reaction solution was extracted with ether, the ether was back extracted with water, and the ether layer was dried over sodium sulfate. Ether was removed in vacuo, and distillation of the oily residue afforded 25.7 g. of (R)-2-bromo-3-benzenepropanoic acid; b.p. 141° (0.55 mm of Hg.); [α] D =+14.5° (c=2.4, chloroform).
A mixture of thioacetic acid (7 ml., 97.9 mmol.) and potassium hydroxide (5.48 g., 97.9 mmol.) in acetonitrile (180.5 ml.) was stirred under argon at room temperature for 13/4 hours. The mixture was cooled in an ice-bath, and a solution of (R)-2-bromo-3-benzenepropanoic acid (20.4 g., 89 mmol.) in acetonitrile (20 ml.) was added over a ten minute period. The reaction was stirred under argon at room temperature for 5 hours, filtered, and the acetonitrile was removed in vacuo. The oily residue was redissolved in ethyl acetate and washed with 10% potassium bisulfate and water. Removal of the ethyl acetate in vacuo afforded 19.6 g. of crude product. The crude product was purified via its dicyclohexylamine salt using isopropyl ether as solvent for crystallization. An analytical sample of (S)-2-(acetylthio) benzenepropanoic acid, dicyclohexylamine salt was prepared by recrystallization from ethyl acetate; m.p. 146°-147°; [α] D =-39.6° (c=1.39, chloro form).
Anal. calc'd. for C 11 H 12 O 3 S·C 12 H 23 N: C,68.11; H,8.70; N,3.45; S,7.91
Found: C,67.93; H,8.71; N,3.37; S,7.94.
g) [4S-[4α,7α(R*),13bβ]]-1,3,4,6,7,8,9,13,13b-Octahydro-7-[[2-(acetylthio)-1-oxo-3-phenylpropyl]amino]-6-oxo-2H-pyrido[1',2':1,2]azepino[3,4-b]indole-4-carboxylic acid, methyl ester
The dicyclohexylamine salt from part (f) (450 mg., 1.11 mmol.) was partitioned between ethyl acetate and 5% potassium bisulfate. The ethyl acetate layer was washed with water and brine, then dried (sodium sulfate), filtered and stripped to give the free acid as a colorless oil. A solution of the acid and the product from part (e) (316 mg., 0.965 mmol.) in dry methylene chloride (11 ml.) was treated with triethylamine (149 μl., 108 mg., 1.07 mmol.). The mixture was cooled to 0° C. and subsequently treated with benzotriazol-1-yloxy-tris(dimethylamino) phosphonium hexafluorophosphate (449 mg., 1.02 mmol.). After stirring at 0° C. for 1 hour and at room temperature for 4.5 hours, the mixture was diluted with ethyl acetate and washed successively with 0.5 N hydrochloric acid, water, and saturated sodium bicarbonate/brine. The ethyl acetate layer was dried (sodium sulfate), filtered and stripped and the residue was flash chromatographed (Merck silica gel, 65:35-ethyl acetate:hexanes) to give 462 mg. of title product as a white foam. TLC (70:30, ethyl acetate:hexane) R f =0.39.
h) [4S-[4α,7α(R*),13bβ]]-1,3,4,6,7,8,13,13b-Octahydro-6-oxo-7-[(2-mercapto-1-oxo-3-phenylpropyl)amino]-2H-pyrido[1',2':1,2]azepino[3,4b]indole-4-carboxylic acid
A solution of the product from part (g) (444 mg., 0.83 mmol.) in methanol (9 ml., deoxygenated via argon bubbling) and tetrahydrofuran (2 ml.) was treated with 1 N sodium hydroxide (10 ml., deoxygenated via argon bubbling) and the mixture was stirred at room temperature with argon bubbling. Additional methanol and tetrahydrofuran were added periodically to replace that lost by evaporation. After 1.5 hours, the mixture was acidified with 1 N hydrochloric acid (15 ml.), diluted with water, and extracted with ethyl acetate. The ethyl acetate extract was washed with brine, dried (sodium sulfate), filtered, and stripped to give a pale yellow residue. The residue was flash chromatographed (Merck silica gel, 1% acetic acid in ethyl acetate). The fractions containing the desired product were pooled, stripped, and azeotroped twice with ethyl acetate. The resulting oil was dissolved in a small amount of ethyl acetate and ethyl ether and triturated with hexane. The resulting foam was collected by filtration and dried in vacuo to give 266 mg, of title product as a hard white foam; [α] D =+15.9° (c=0.5, chloroform). TLC (1% acetic acid in ethyl acetate) R f =0.39. HPLC: YMC S3 ODS column (6.0×150 mm); eluted with 40% A: 90% water-10% methanol-0.2% phosphoric acid and 60% B: 10% water-90% methanol-0.2% phosphoric acid; flow rate 1.5 ml/min detecting at 220 nm; t R =20.46 min indicates a purity of 96.3%.
Anal. calc'd. for C 26 H 27 N 3 O 4 S·0.7 H 2 O: C, 63.71; H, 5.84; N, 8.57; S, 6.54
Found: C, 63.61; H, 5.94; N, 8.23; S, 6.32.
EXAMPLE 2
[5S-[5α(R*),8α,11αβ]]-5,6,9,10,11,11a-Hexahydro-5-[(2-mercapto-1-oxo-3-phenylpropyl)amino]-6-oxo-4H,8H-pyrido[1,2-a]thieno[3,2-c]azepine-8-carboxylic acid
a) N-Phthalimido-3-(2-thienyl)-L-alanine
3-(2-Thienyl)-L-alanine(2.24 g., 13.1 mmol.) was suspended in water/p-dioxane (20 ml./10 ml.) at room temperature under argon. Sodium carbonate (1.39 g.) was added and the mixture was stirred until homogeneous. N-Carbethoxyphthalimide (2.87 g.) was added, and the resulting mixture was stirred for 4.5 hours and then cooled to 0° C. The pH was adjusted to 1.5 with 6 N hydrochloric acid and the mixture was extracted with ethyl acetate. The organic layer was washed successively with 10% potassium bisulfate and brine, dried (sodium sulfate), filtered, and concentrated. The crude product was flash chromatographed (Merck silica gel) eluting with 1:1 ethyl acetate/hexane/1% acetic acid. The fractions containing clean desired product were combined, concentrated, azeotroped with ethyl acetate, and washed with water to remove the acetic acid. The organic layer was dried (sodium sulfate), filtered, and concentrated to give 2.70 g. of the title compound as a white crystalline product; m.p. 166°-168° C.; [α] D =-153.6° (c=0.46, methylene chloride). TLC (1% acetic acid in 1:1 ethyl acetate/hexane) R f =0.5.
b) N-[N-Phthalimido-3-(2-thienyl)-L-alanyl]-6-hydroxy-L-norleucine, methyl ester
N-Methylmorpholine (1.51 ml., 14.5 mmol.) was added to a solution of 6-hydroxy-L-norleucine, methyl ester, hydrochloride (8.53 mmol.) in methylene chloride (34 ml)/dimethylformamide (9 ml.) at room temperature under argon. The resulting mixture was cooled to 0° C. and N-phthalimido-3-(2-thienyl)-L-alanine (2.57 g., 8.54 mmol.), hydroxybenzotriazole (1.19 g., 8.80 mmol.) and 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (1.80 g., 9.4 mmol.) were added sequentially. After stirring at 0° C. for 30 minutes, the mixture was warmed to room temperature and stirred for 1.5 hours. The volatiles were evaporated and the residue was partitioned between ethyl acetate and water. The organic layer was washed successively with 0.5 N hydrochloric acid, water, saturated sodium bicarbonate, and brine, and the organic layer was dried (sodium sulfate), filtered, and concentrated. The residue was flash chromatographed (Merck silica gel) eluting with 2:1 ethyl acetate/hexane to give 3.13 g. of title compound as a white foam. TLC (5% acetic acid in ethyl acetate) R f =0.68.
c) N-[N-Phthalimido-3-(2-thienyl)-L-alanyl]-6-oxo-L-norleucine, methyl ester
To a solution of 4-methylmorpholine N-oxide (1.12 g., 9.6 mmol., pre-dried over magnesium sulfate) and the product from part (b) (2.83 g., 6.37 mmol.) was added 4A molecular sieves and tetrapropyl ammoniumperruthenate (200 mg.). The resulting mixture was stirred for 2 hours at room temperature. The mixture was filtered through Celite and the volatiles were evaporated. The residue was flash chromatographed (Merck silica gel) eluting with 1:1 ethyl acetate/hexane to give 1.54 g. of title compound as white crystals; m.p. 125°-126° C.; [α] D =-70.3° (c=0.46, methylene chloride). TLC (1:1, ethyl acetate/hexane) R f =0.27.
d) (S)-1-[N-Phthalimido-3-(2-thienyl)-L-alanyl]-4-tetrahydro-2-pyridinecarboxylic acid, methyl ester
Trifluoroacetic acid (73 μl) was added to a solution of the product from part (c) (1.53 g., 3.45 mmol.) in methylene chloride (36 ml.) at room temperature under argon. The mixture was gently refluxed for 3.5 hours. After cooling to room temperature, the mixture was washed with 50% saturated sodium bicarbonate, dried (sodium sulfate), filtered, and concentrated. The residue was flash chromatographed (Merck silica gel) eluting with 2:1 hexane/ethyl acetate to give 1.22 g. of title compound as a white foam. TLC (3:2, hexane/ethyl acetate) R f =0.42.
e) [5S-[5α,8α,11aβ]]-5,6,9,10,11,11a-Hexahydro-6-oxo-5-phthalimido-4H,8H-pyrido[1,2-a]thieno[3,2-c]azepine-8-carboxylic acid, methyl ester
The product from part (d) (1.16 g., 2.74 mmol.) was dissolved in methylene chloride (35 ml.) at room temperature under argon. Trifluoromethanesulfonic acid (1.82 ml.) was added and the resulting mixture was stirred for 1 hour. The mixture was poured into ice water and extracted with ethyl acetate. The organic layer was washed with brine, dried (sodium sulfate), filtered and concentrated to give 1.1 g of a yellow solid-like residue. The residue was dissolved in methylene chloride (8 ml.)/methanol (10 ml.) and cooled to 0° C. The mixture was treated with excess diazomethane for 5 minutes. The excess diazomethane was destroyed with acetic acid and the volatiles were removed. The yellow residue was flash chromatographed (Merck silica gel) eluting with 2:1 hexane/ethyl acetate to give 720 mg. of a white crystalline product. Recrystallization from hot ethyl acetate/hexane gave 670 mg. of analytically pure title compound; m.p. 163.5°-164° C.; [α] D =-119.5° (c=0.43, methylene chloride). TLC (2:1, hexane/ethyl acetate) R f =0.15.
f) [5S-[5α,8α,11aβ]]-5,6,9,10,11,11a-Hexahydro-5-amino-6-oxo-4H, 8H-pyrido[1,2-a]thieno[3.2-c]azepine-8-carboxylic, methyl ester
The product from part (e) (670 mg., 1.58 mmol.) was suspended in methanol (8 ml.) at room temperature under argon. The mixture was treated with hydrazine monohydrate (0.17 ml.), became homogeneous, and was stirred for 16 hours. The mixture was filtered to remove the white precipitate and the filtrate was stripped, treated with methylene chloride, filtered and stripped again to give a white crystalline solid. The solid was recrystallized from hot ethyl acetate and hexane to give 372 mg. of title compound as white needle-like crystals; m.p. 151°-154° C.; [α] D =-20-9° (c=0.47, methylene chloride). TLC (4% methanol in methylene chloride) R f =0.39.
g) [5S-[5α(R*),8α,11aβ]]-5,6,9,10,11,11a-Hexahydro-5-[[2-(acetylthio)-1-oxo-3-phenylpropyl]amino]-6-oxo-4H,8H-pyrido[1,2-a]thieno[3,2-c]azepine-8-carboxylic acid, methyl ester
(S)-2-(Acetylthio)benzenepropionic acid, dicyclohexylamine salt (589 mg., 1.45 mmol.) was partitioned between ethyl acetate and 10% potassium bisulfate. The organic layer was washed with brine, dried (sodium sulfate), filtered, and concentrated to give (S)-2-(acetylthio) benzenepropanoic acid as an oil. The residue was dissolved in methylene chloride (15 ml.) at room temperature under argon. Following the addition of the product from part (f) (371 mg., 1.26 mmol.), the mixture was cooled to 0° C. and triethylamine (0.19 ml., 1.39 mmol.) was added. The resulting mixture was stirred for 5 minutes then benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (585 mg., 1.32 mmol.) was added. After being stirred at 0° C. for 1 hour, the reaction mixture was warmed to room temperature and was stirred for 16 hours. The volatiles were evaporated and the residue was dissolved in ethyl acetate and washed successively with 1 N hydrochloric acid, water, 50% saturated sodium bicarbonate, and brine. The organic layer was dried (sodium sulfate), filtered, and concentrated and the residue was flash chromatographed (Merck silica gel ) eluting with 3:2 hexane/ethyl acetate to give 508 mg. of the desired product as a white foam. TLC (1:1, ethyl acetate/hexane) R f =0.64.
h) [5S-[5α(R*),8 α,11aβ]]-5,6,9,10,11,11a-Hexahydro-5-[(2-mercapto-1-oxo-3-phenylpropyl)amino]-6-oxo-4H,8H-pyrido[1,2-a]thieno[3,2-c]azepine-8-carboxylic acid
A solution of the product from part (g) (496 mg., 1.1 mmol.) in methanol (10 ml., deoxygenated via argon bubbling) was cooled to 0° C. and treated with 1 N sodium hydroxide (8 ml., deoxygenated via argon bubbling). The resulting mixture was stirred under argon for 1 hour. The mixture was warmed to room temperature and stirred an additional 2.5 hours. The mixture was acidified with 10% potassium bisulfate and extracted with ethyl acetate. The organic layer was washed successively with water and brine, dried (sodium sulfate), filtered and concentrated to give a yellow oil. This residue was flash chromatographed (Merck silica gel) eluting with 1% acetic acid in 3:2 hexane/ethyl acetate. The fractions containing pure product were combined, concentrated, azeotroped with ethyl acetate, and washed with water to remove any acetic acid. The organic layer was dried (sodium sulfate), filtered and concentrated. The residue was taken up in ethyl acetate and triturated with hexane. The solvent was removed and the residue was slurried in hexane, stripped, and dried in vacuo to give 416 mg. of title product as a white powdery foam; [α] D =+24.0° (c=0.52, methanol). TLC (2% acetic acid in ethyl acetate) R f =0.84.
HPLC: YMC S-3 ODS (C- 18) 6.0×150 mm; 64% (10% water-90% methanol-0.2% phosphoric acid)/36% (90% water-10% methanol-0.2% phosphoric acid), flow rate=1.5 ml/min, isocratic, detecting at 220 nm; t R =11.8 min. indicates a purity of 95%.
Anal. calc'd. for C 22 H 24 N 2 O 4 ·0.8 water·0.25 hexane ·0.25 ethyl acetate C, 58.55; H, 6.24; N, 5.57; S, 12.76;
Found C, 58.55; H, 5.88; N, 5.64; S, 12.56.
EXAMPLE 3
[5S-[5α(R*),8α,11aβ]]-5,6,9,10,11,11a-Hexahydro-5-[(2-mercapto-1-oxo-3-phenylpropyl)amino]-6-oxo-4H,8H-pyrido[1,2-a]thieno[2,3-c]azepine-8-carboxylic acid
a) N-Phthalimido-3-(3-thienyl)-L-alanine
3-(3-Thienyl)-L-alanine (2.45 g., 14.3 mmol.) was suspended in water/p-dioxane (22 ml/11 ml.) at room temperature under argon. Sodium carbonate (1.52 g.) was added and the mixture was stirred until homogeneous. N-Carbethoxyphthalimide (3.14 g.) was added, and the resulting mixture was stirred for 3.0 hours and then cooled to 0° C. The pH was adjusted to 1.5 with 6 N hydrochloric acid and the mixture was extracted with ethyl acetate. The organic layer was washed successively with 10% potassium bisulfate and brine, dried (sodium sulfate), filtered, and concentrated. The crude product was flash chromatographed (Merck silica gel) eluting with 1:1 ethyl acetate/hexane/1% acetic acid. The fractions containing clean desired product were combined, concentrated, azeotroped with ethyl acetate, and washed with water to remove the acetic acid. The organic layer was dried (sodium sulfate), filtered, and concentrated to give 3.22 g. of title compound as a white crystalline product; m.p. 166°-168° C.; [α] D =-146.8° (c=0.46, methylene chloride). TLC (1% acetic acid in 1:1 ethyl acetate/hexane) R f =0.31.
b) N-[N-Phthalimido-3-(3-thienyl)-L-alanyl]-6-hydroxy-L-norleucine, methyl ester
N-Methylmorpholine (1.89 ml., 18.12 mmol.) was added to a solution of 6-hydroxy-L-norleucine, methyl ester, hydrochloride (10.66 mmol.) in methylene chloride (41 ml.)/dimethylformamide (11 ml.) at room temperature under argon. The resulting mixture was cooled to 0° C. and N-phthalimido-3-(3-thienyl)-L-alanine (3.21 g., 10.66 mmol.), hydroxy-benzotriazole (1.48 g., 10.98 mmol.), and 1-ethyl-3-(3dimethylaminopropyl)carbodiimide (2.25 g., 11.73 mmol.) were added sequentially. After stirring at 0° C. for 30 minutes, the mixture was warmed to room temperature and stirred for 2 hours. The volatiles were evaporated and the residue was partitioned between ethyl acetate and water. The organic layer was washed successively with 0.5 N hydrochloric acid, water, saturated sodium bicarbonate, and brine, and the organic layer was dried (sodium sulfate), filtered, and concentrated. The residue was flash chromatographed (Merck silica gel) eluting with 4:1 ethyl acetate/hexane to give 3.8 g. of title compound as a white foam. TLC (ethyl acetate) R f =0.56.
c) N-[N-Phthalimido-3-(3-thienyl)-L-alanyl]-6-oxo-L-norleucine, methyl ester
Oxalyl chloride (0.84 ml., 9.78 mmol.) was added to a flask containing methylene chloride (40 ml.) at -78° C. under argon. Following the dropwise addition of dimethylsulfoxide (1.39 ml., 19.56 mmol.) in methylene chloride (2 ml.), the mixture was stirred for 20 minutes. A solution of the product from part (b) (3.62 g., 8.15 mmol.) in methylene chloride (20 ml.) was added, the mixture was stirred for 15 minutes, triethylamine (7.0 ml.) was added, and the mixture was stirred for 5 minutes. After warming to room temperature, the mixture was partitioned between ethyl acetate and 0.5 N hydrochloric acid and the organic layer was washed with brine, dried (sodium sulfate), filtered, and concentrated to obtain white crystals. The crystals were triturated with ethyl ether and collected by filtration to give 3.04 g. of title compound; m.p. 102°-104° C.; [α] D =-58.0° (c=0.68, methylene chloride). TLC (ethyl acetate) R f =0.83.
d) (S)-1-[N-Phthalimido-3-(3-thienyl)-L-alanyl]-4-tetrahydro-2-pyridinecarboxylic acid, methyl ester
Trifluoroacetic acid (0.15 ml.) was added to a solution of the product from part (c) (3.02 g., 6.83 mmol.) in methylene chloride (70 ml.) at room temperature under argon. The mixture was gently refluxed for 3 hours. After cooling to room temperature, the mixture was washed with 50% saturated sodium bicarbonate, dried (sodium sulfate), filtered, and concentrated. The residue was flash chromatographed (Merck silica gel) eluting with 3:2 hexane/ethyl acetate to give 2.49 g. of title compound as a white foam. TLC (3:2, hexane/ethyl acetate) R f =0.44.
e) [5S-[5α,8α,11aβ]]-5,6,9,10,11,11a-Hexahydro-6-oxo-5-phthalimido-4H,8H-pyrido[1,2-a]thieno[2,3-c]azepine-8-carboxylic acid, methyl ester
The product from part (d) (2.29 g., 5.40 mmol.) was dissolved in methylene chloride (70 ml.) at room temperature under argon. Trifluoromethanesulfonic acid (3.6 ml.) was added and the resulting mixture was stirred for 0.5 hour. The mixture was poured into ice water and extracted with ethyl acetate. The organic layer was washed with brine, dried (sodium sulfate), filtered and concentrated to give a dark orange oil. The residue was dissolved in methylene chloride (15 ml.)/methanol (20 ml.) and cooled to 0° C. The mixture was treated with excess diazomethane for 5 minutes. The excess diazomethane was destroyed with acetic acid and the volatiles were removed. The residue was flash chromatographed (Merck silica gel) eluting with 1:1 hexane/ethyl acetate to give 441 mg. of title compound as a white crystalline product; m.p. 132°-134° C.; [α] D =-87.4° (c=0.47, methylene chloride). TLC (1:1, hexane/ethyl acetate) R f =0.5.
f) [5S-[5α,8α,11aβ]]-5,6,9,10,11,11a-Hexahydro-5-amino-6-oxo-4H,8H-pyrido[1,2-a]thieno[2,3-c]azepine-8-carboxylic acid, methyl ester
The product from part (e) (370 mg., 0.87 mmol.) was suspended in methanol (8 ml.) at room temperature under argon. After methylene chloride (4 ml.) was added to effect a homogeneous mixture, the mixture was treated with hydrazine monohydrate (0.09 ml., 1.92 mmol., 2.2 equiv.) and was stirred for 1.5 hours. The volatiles were evaporated and the residue was chased with toluene (×2). The residue was redissolved in methanol and stirred at room temperature for 72 hours. The mixture was filtered to remove the white precipitate and the filtrate was stripped, treated with methylene chloride, filtered and stripped again to give 300 mg. of title product as a yellow oil. TLC (4% methanol in methylene chloride) R f =0.63.
g) [5S-[5α(R*),8α,11aβ]]-5,6,9,10,11,11a-Hexahydro-5-[[2-(acetylthio)-1-oxo-3-phenylpropyl]amino]-6-oxo-4H,8H-pyrido[1,2-a]thieno[2,3-c]azepine-8-carboxylic acid, methyl ester
(S)-2-(Acetylthio)benzenepropanoic acid, dicyclohexylamine salt (406 mg., 1.0 mmol.) was partitioned between ethyl acetate and 10% potassium bisulfate. The organic layer was washed with brine, dried (sodium sulfate), filtered, and concentrated to give (S)-2-(acetylthio)benzenepropanoic acid as an oil. The residue was dissolved in methylene chloride (10 ml.) at room temperature under argon. Following the addition of the product from part (f) (0.87 mmol.), the mixture was cooled to 0° C. and triethylamine (0.13 ml., 0.96 mmol.) was added. The resulting mixture was stirred for 5 minutes then benzotriazol-1-yloxytris(dimethylaminopropyl)-phosphonium hexafluorophosphate (403 mg., 0.91 mmol.) was added. After being stirred at 0° C. for 1 hour, the reaction mixture was warmed to room temperature and was stirred for 16 hours. The volatiles were evaporated and the residue was dissolved in ethyl acetate and washed successively with 1 N hydrochloric acid, water, 50% saturated sodium bicarbonate, and brine. The organic layer was dried (sodium sulfate), filtered, and concentrated and the residue was flash chromatographed (Merck silica gel) eluting with 3:2 hexanemethyl acetate to give 367 mg. of the desired product as a yellow oil. TLC (1:1, ethyl acetate/hexane) R f =0.52.
h) [5S-[5α(R*),8α,11aβ]]-5,6,9,10,11,11a-Hexahydro-5-[(2-mercapto-1-oxo-3-phenylpropyl)amino]-6-oxo-4H,8H-pyrido[1,2-a]thieno[2,3-c]azepine-8-carboxylic acid
A solution of the product from part (g) (365 mg., 0.78 mmol.) in methanol (8 ml., deoxygenated via argon bubbling) was cooled to 0° C. and treated with 1 N sodium hydroxide (6 ml., deoxygenated via argon bubbling). The resulting mixture was stirred under argon for 0.5 hour. The mixture was warmed to room temperature and stirred an additional 4.5 hours. The mixture was acidified with 10% potassium bisulfate and extracted with ethyl acetate. The organic layer was washed successively with water and brine, dried (sodium sulfate), filtered and concentrated to give a yellow oil. This residue was flash chromatographed (Merck silica gel) eluting with 1% acetic acid in 3:2 hexane/ethyl acetate. The fractions containing pure product were combined, concentrated, azeotroped with ethyl acetate, and washed with water to remove any acetic acid. The organic layer was dried (sodium sulfate), filtered and concentrated. The residue was taken up in ethyl acetate and triturated with hexane. The solvent was removed and the residue was slurried in hexane, stripped, and dried in vacuo to give 310 mg. of title compound as a white powdery foam; [α] D =+29.8° (c=0.38, methylene chloride). TLC (2% acetic acid in ethyl acetate) R f =0.82.
HPLC: YMC S-3ODS (C- 18) 6.0×150 mm; 65% (10% water-90% methanol-0.2% phosphoric acid)/35% (90% water-10% methanol-0.2% phosphoric acid), flow rate=1.5 ml/min, isocratic, detecting at 220 nm; t r =11.9 min indicates a purity of 99.2%
Anal. calc'd. for C 22 H 24 N 2 O 4 S 2 ·1.0 H 2 O: C, 57.05; H, 5.67; N, 6.05; S, 13.84;
Found C, 57.15; H, 5.56; N, 5.95; S, 13.30.
EXAMPLE 4
1000 tablets each containing the following ingredients:
______________________________________[5S-[5α(R*),8α,11aβ]]-5,6,9,10,11, 200 mg.11a-Hexahydro-5-[(2-mercapto-1-oxo-3-phenylpropyl)amino]-6-oxo-4H,8H-pyrido[1,2-a]thieno[2,3-c]azepine-8-carboxylic acidCornstarch 100 mg.Gelatin 20 mg.Avicel (microcrystalline cellulose) 50 mg.Magnesium stearate 5 mg. 375 mg.______________________________________
are prepared from sufficient bulk quantities by mixing the product of Example 3 and cornstarch with an aqueous solution of the gelatin. The mixture is dried and ground to a fine powder. The Avicel and then the magnesium stearate are admixed with granulation. The mixture is then compressed in a tablet press to form 1000 tablets each containing 200 mg. of active ingredient.
In a similar manner, tablets containing 200 mg. of the product of Examples 1 or 2 can be prepared.
Similar procedures can be employed to form tablets or capsules containing from 50 mg. to 500 of active ingredient. | Compounds of the formula ##STR1## are useful as intermediates in the preparation of compounds possessing ACE and NEP inhibition activity. | 2 |
CROSS REFERENCE TO RELATED APPLICATION APPLICATIONS
This application is a continuation of U.S. application Ser. No. 13/328,779, filed Dec. 16, 2011 (now U.S. Pat. No. 8,523,623), which is a continuation of U.S. application Ser. No. 12/890,240, filed Sep. 24, 2010 (now U.S. Pat. No. 8,079,888), which is a continuation of U.S. application Ser. No. 12/400,214, filed Mar. 9, 2009 (now U.S. Pat. No. 7,811,145), which is a continuation of U.S. application Ser. No. 12/028,227, filed Feb. 8, 2008 (now U.S. Pat. No. 7,500,893), which is a continuation of U.S. application Ser. No. 11/554,197, filed Oct. 30, 2006 (now U.S. Pat. No. 7,335,080), which is a continuation of Ser. No. 11/143,703, filed Jun. 3, 2005 (now U.S. Pat. No. 7,134,930), which is a continuation of U.S. application Ser. No. 10/847,339, filed May 18, 2004 (now U.S. Pat. No. 7,147,528), which is a continuation of U.S. application Ser. No. 10/295,906, filed Nov. 18, 2002, (now U.S. Pat. No. 7,097,524), which is also a continuation of U.S. application Ser. No. 09/772,739, filed Jan. 30, 2001, (now U.S. Pat. No. 6,485,344), which claims priority from U.S. Provisional Application Ser. No. 60/238,988, filed Oct. 10, 2000; the entire disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to inflatable flotation devices. In particular, the present invention relates to inflatable flotation devices which are collapsible through use of a spring mechanism.
2. Description of the Related Art
Inflatable flotation devices are well known in the form of floats, rafts, lifeboats, life preservers and other like devices. Previously known devices generally maintain their shape through air pressure alone and generally collapse when deflated.
In one of many examples, U.S. Pat. No. 3,775,782 issued to Rice et al. describes an inflatable rescue raft. When deflated, the raft can be rolled into a compact size.
Also well known in the art are collapsible items which are collapsible through the use of a collapsible metal or plastic spring. U.S. Pat. No. 4,815,784 shows an automobile sun shade which uses these collapsible springs. The springs are also used in children's play structures (U.S. Pat. Nos. 5,618,246 and 5,560,385) and tent-like shade structures (U.S. Pat. Nos. 5,579,799 and 5,467,794).
The collapsible springs are typically retained or held within fabric sleeves provided along the edges of a piece of fabric or other panel. The collapsible springs may be provided as one continuous loop, or may be a strip or strips of material connected at the ends to form a continuous loop. These collapsible springs are usually formed of flexible coilable steel, although other materials such as plastics are also used. The collapsible springs are usually made of a material which is relatively strong and yet is flexible to a sufficient degree to allow it to be coiled. Thus, each collapsible spring is capable of assuming two configurations, a normal uncoiled or expanded configuration, and a coiled or collapsed configuration in which the spring is collapsed into a size which is much smaller than its open configuration. The springs may be retained within the respective fabric sleeves without being connected thereto. Alternatively, the sleeves may be mechanically fastened, stitched, fused, or glued to the springs to retain them in position.
SUMMARY OF THE DISCLOSURE
A device comprises a spring and a sleeve. The spring is configured to form a closed loop. The spring is moveable between a coiled configuration when the spring is collapsed and an uncoiled configuration when the spring is expanded. The spring defines a circumference while in the uncoiled configuration. The spring is disposed within the sleeve. The sleeve includes an inflatable portion disposed about at least a portion of the circumference.
It is therefore an object of the present invention to provide a collapsible flotation device.
It is another object of the present invention to provide a collapsible flotation device which is easily collapsed and extended to full size through a mechanical means.
It is yet another object of the present invention to provide a collapsible flotation device which is easily collapsed and extended to full size through the use of a spring.
It is yet a further object of the present invention to provide a collapsible flotation device which requires minimal force to twist and fold into the collapsed configuration.
Finally, it is an object of the present invention to accomplish the foregoing objectives in a simple and cost effective manner.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of the preferred embodiment of the present invention;
FIG. 2 is a cross sectional view of the preferred embodiment of the present invention taken along line II-II of FIG. 1 ;
FIG. 3 is a view of a joining method as used in one embodiment of the present invention;
FIG. 4 is a top view of an alternate embodiment of the present invention;
FIG. 5 is a top view of another alternate embodiment of the present invention;
FIG. 6 is a cross section view of the alternate embodiment of the present invention across line VI-VI of FIG. 5 ;
FIG. 7 is a top view of an alternative embodiment of the present invention;
FIG. 8 is a cross sectional view of the embodiment of the present invention, taken along line VIII-VIII of FIG. 7 ; and
FIG. 9 is a plan view of another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following detailed description is of the best presently contemplated modes of carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating general principles of embodiments of the invention.
The present invention provides a collapsible flotation device. The device includes a coilable metal or plastic spring. The coilable spring can be made from other materials, however, it is important that the coilable spring be made from a material that is strong and flexible. The spring must be coilable such that it folds on top of itself to become more compact. In its uncoiled state, the coilable spring can be round or oval or any shape satisfactory for use as a flotation device. Because it is to be used in water, the coilable spring is preferably either manufactured from a waterproof material or coated to protect any material which is not waterproof. The coilable spring can be a single continuous element or can include a joining means, such as a sleeve, for joining the ends of one or more spring elements together. The coilable spring can be of any appropriate shape and dimension. The coilable spring also has memory such that is biased to return to its uncoiled configuration when not held in the coiled configuration.
Stretched across the coilable spring is a flexible panel of material. The flexible panel can be one continuous piece or can be made up of several different types of material. In a preferred embodiment, the center portion of the flexible panel is mesh to allow water to flow through while the perimeter edges are nylon or polyester. At the edges of the flotation device, the material is a double thickness, forming a pocket around the perimeter of the flotation device. In this pocket are one or more inflatable chambers. One inflatable chamber may surround the entire perimeter of the flotation device or it may be divided into two or more inflatable chambers with each inflatable chamber having a means for inflating and deflating the inflatable chamber. In a preferred embodiment, one inflatable chamber is specifically designed to accommodate the user's head. In this embodiment, the pocket formed by the material is wider along a small portion of the perimeter of the flotation device to allow for a wider inflatable chamber. This will prevent the user's head from sinking below the rest of the user's body. The size of the inflatable chamber can vary significantly and need only be as wide as necessary to support the user's body weight. A preferred embodiment includes an inflatable chamber which is 3 inches in diameter when inflated. The inflatable chamber can be made from any appropriate float material but is preferably resistant to punctures. The coilable spring may also be located within the perimeter pocket. If one inflatable chamber is selected, the coilable spring can be placed inside or outside the inflatable chamber. If multiple inflatable chambers are used, the coilable spring will be outside the inflatable chambers. Alternatively, the coilable spring may be located outside the perimeter pocket along the outer edge of the flotation device. The coilable spring may be attached to the flexible panel through mechanical means such as fastening, stitching, fusing, or gluing.
A preferred embodiment of the flotation device is shown in FIGS. 1 and 2 in its expanded configuration. The perimeter pocket 12 portion of the flexible panel is nylon while the central portion 14 of the flexible panel is made from a mesh material. The pillow 16 is part of the perimeter pocket 12 as it includes a double layer of fabric to accept an inflatable chamber 20 between the layers of fabric. In this particular embodiment, there are two inflatable chambers 20 in the perimeter pocket of the flotation device and one in the pillow 16 , each of which includes a means for inflating the inflatable chamber 20 . The inflation means is a valve on the underside of the flotation device. The inflatable chambers 20 in the perimeter pocket of the flotation device expand to approximately a 3-inch diameter when inflated. The coilable spring 18 is made from flexible, collapsible steel and is coated with a layer of PVC 22 to protect the coilable spring 18 from corroding and rusting due to contact with water during normal use of the flotation device. The coilable spring 18 also has memory such that will open to its uncoiled configuration when not held in the coiled configuration. The coilable spring 18 can be a single unitary element or can include sleeves 24 for joining the ends of one or more strips as shown in FIG. 3 in which the ends of the coilable spring 18 within the sleeve 24 are shown in dashed lines for clarification.
Alternatively or in addition to the perimeter inflatable chambers, the device can include inflatable chambers 26 which cross the panel as shown in FIG. 4 . FIGS. 5 and 6 show a further alternate embodiment of the present invention in which the coilable spring 18 is attached to the external perimeter of the pocket portion 12 of the flexible panel through the use of a mechanical means. In this particular embodiment, several loops 28 are used to attach the coilable spring 18 to the pocket portion 12 of the flexible panel.
While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention. | A device comprises a spring and a sleeve. The spring is configured to form a closed loop. The spring is moveable between a coiled configuration when the spring is collapsed and an uncoiled configuration when the spring is expanded. The spring defines a circumference while in the uncoiled configuration. The spring is disposed within the sleeve. | 1 |
BACKGROUND OF THE INVENTION
It is known to machine bores with an extremely high accuracy of size using arbor or mandrel honing. Examples are the machining of very small bores for car injection systems, the machining of bores in hydraulic components and the machining of the large and small offices in connecting rods.
In the case of arbor honing the honing tool set to the final diameter is moved at high rotation speed, but low stroke speed at least once and at the most three times through the bore. As a result of the high circumferential speed of the honing tool compared with the stroke speed, the honing angle during arbor honing is very small.
The problem of the invention is to further develop a honing method, whilst retaining the advantages obtained by arbor honing, with regards to a tribologically favourable surface topography.
SUMMARY OF THE INVENTION
Whereas during normal arbor honing using an arbor honing tool, the bore is only slowly traversed with a high rotational speed, the invention proposes that the arbor honing tool be at least partly used in a manner not conventional in the case of arbor honing. With a small allowance for the bore to be machined, e.g. the first stroke with the arbor honing tool can be run through with an increased stroke speed to rotational speed ratio, i.e. in other words very rapidly.
If said allowance is not as small, e.g. the first stroke, i.e. the first passage through the bore can take place at the normal speed and subsequently the tool can be rapidly retracted. Under the indicated conditions, this can also lead to the production of a cross-structure.
However, according to a further development, the bore is initially machined in the conventional manner with a stroke and a return stroke and only then is the arbor honing tool used in the unconventional manner.
Thus, the bore to be machined is machined in the same way as hitherto. Use is made of an arbor honing tool, which is moved through the bore in at least one stroke and a return stroke at a high rotational speed, but low stroke speed. Subsequently either the circumferential speed is modified or the stroke speed increased. Then, using the same tool, the bore is machined again, but now as a result of the higher stroke speed compared with the rotational speed, there is a larger angle of the honing tracks. On retraction it can be ensured that a cross-structure is obtained, which then leads to the desired, improved tribological characteristics.
As a result of the characteristics of an arbor honing tool, which undergoes stress relief, the possibility arises during the return stroke that the abrasion is deeper than the honing tracks of the forward stroke. In certain circumstances this can lead to a risk of no cross-structure being formed. In order to obviate this risk in all cases, according to a further development of the invention the tool is reset prior to the remachining return stroke and is consequently stress-relieved. This resetting or stress relief can take place to such an extent that the honing tracks occurring during the return stroke have the same depth as those formed during the forward stroke.
However, it is also possible and is proposed by the invention, to perform remachining with several and in particular rapid strokes, so that as a result of the plurality of strokes there are cross-structures having the same depth.
A further infeeding of the tool is possible, so as to reliably cover the previously formed tracks.
It is also possible during the downward stroke to make the abrasion so small that in the case of a fixed set tool during the upward stroke not all the tracks of the downward stroke are abraded.
According to a further development of the invention, following onto remachining a further remachining takes place, in which the peaks of the surface structure are smoothed. This constitutes a type of plateau machining in order to be able to produce a specific support structure.
According to the invention, the same tool as for the preceding remachining can be used for said smoothing.
However, it is also possible and is proposed by the invention that the smoothing of the peaks can take place with the aid of another tool by means of arbor honing or normal honing.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features, details and advantages of the invention can be gathered from the following description of a preferred embodiment thereof, the claims, whose wording is by reference made into part of the content of the description, and the attached drawings, wherein show:
FIG. 1 A schematic view of the cross-section through a bore prior to the start of the honing proposed by the invention.
FIG. 2 A schematic view of the bore after the first stroke.
FIG. 3 A schematic view of the bore after the first return stroke.
FIG. 4 A schematic view of the bore after the first remachining stroke.
FIG. 5 A schematic view of the bore at the end of remachining.
FIG. 6 A schematic view of the bore for machining with a different tool.
DETAILED DESCRIPTION
FIG. 1 diagrammatically shows the cross-section through a work-piece 1 with the bore 2 contained therein. The bore 2 has resulted from a preceding machining step and has been brought to a particular size by grinding, turning or some other machining method. The structure of the bore 2 is now to be smoothed and it is to be brought to its finished size. For this purpose a honing tool 3 is used, which is in fact a mandrel or arbor honing tool. This tool 3 contains a front, slightly conical cutting zone 4 , which is shown in highly exaggerated form in the diagrammatic drawing. The tool 3 is moved at high rotational speed and low travel or stroke speed through the bore 2 , so that there is an abrasion of the wall of the bore 2 , i.e. the surface. The diameter of the bore increases and following the passage of the tool 3 has a surface structure with honing tracks 5 . The state after the first passage of the tool 3 through the bore 2 is shown in FIG. 2 . The honing tracks 5 are almost parallel to the surface 6 of the workpiece 1 or expressed differently almost perpendicular to the rotation axis of the honing tool 3 . This angle differing only slightly from zero results from the high rotational speed of the tool compared with the stroke speed.
Following the first passage through the bore 2 , the tool 3 is retracted again, so that it assumes the position shown in FIG. 3 . During retraction new honing tracks 5 are produced, which are once again very shallow as a result of the kinematics described. However, they now have a different orientation, because the honing tracks obtained during retraction in the example shown are deeper than the previously produced honing tracks. As a result only the honing tracks produced during the return stroke remain visible. Up to this point the honing method corresponds to a conventional arbor honing method.
Now in a following re-machining process the speed of the honing tool 3 is reduced and/or its stroke speed increased. After the first re-machining stroke, the honing tracks 5 shown in FIG. 4 are obtained, and which are now disposed at a much larger angle. The angle corresponds to the angle during a conventional honing method, which functions with numerous strokes. In order to produce this structure of the honing tracks a single stroke is not sufficient, because the abrasion of the material in the preceding operation has already taken place by arbor honing. The tool 3 must now be retracted again through the bore 2 . As a result of a small diameter difference between the tool and the workpiece, the abrasive grains here only have a limited penetration depth. The tracks of the preceding downward stroke are retained. The small diameter difference can, in certain circumstances, be brought about in that the tool is somewhat relieved, so that its external diameter is slightly reduced to profile 3 ′ shown in FIG. 5 . This makes it possible for the honing tracks occurring during retraction to have the same depth as the honing tracks occurring during the forward stroke and as shown in FIG. 4 . Thus, a structure of the honing tracks is obtained in the manner shown in FIG. 5 after retracting the honing tool. Peaks may be formed in the surface structure as result of the re-machining operation. These peaks can be reduced or flattened by using the same tool or a different tool 7 as shown in FIG. 6 .
The invention combines the advantages of arbor honing with the advantages of normal honing. The advantages of arbor honing, such as a high cylinder size accuracy, low tool costs, low machine costs and limited machining and subsidiary times can be combined with a tribologically suitable surface topography, as can be achieved using normal honing. | A honing method proposes that using an arbor honing tool a remachining be carried out using the same tool either simultaneously or following onto arbor honing, in which the ratio of the stroke speed to the rotational speed of the tool is significantly increased. This leads to a cross-structure of the honing tracks allowing a better oil holding capacity. | 1 |
This application is a continuation-in-part of application Ser. No. 785,679 filed Apr. 7, 1977, now abandoned. The latter is a continuation of application Ser. No. 705,102 filed June 14, 1975 (now abandoned).
The present invention relates to methods for protecting proteic foodstuffs against spoilage and, more specifically, to novel, improved processes of that character which do not require refrigeration of the foodstuff.
The process has two stages, one denominated the stabilizing stage and the other called the recovery stage. In the first stage the foodstuff--an animal ("animal" is used generically herein to identify mammals, birds, fishes, selachii, crustaceans, etc.) or part thereof--is immersed in a stabilizing liquid composed of an acid or alkaline buffer solution, a proteolytic enzyme which is active in an acid or alkaline medium, depending upon the pH of the stabilizing liquid, and an antioxidant. Thereafter, the product may be stored at room temperature in either closed or open containers.
The second stage is composed of three steps. In the first step, the pH of the foodstuff is adjusted to a preferred level by immersing the product in an acid or alkaline solution. This results in a rapid change of pH from acid to alkaline or vice versa which has been given the name "ionic blow".
In the second step, carried out after the product has been drained, the product is placed in another receptacle which contains a hypertonic solution at a selected pH to dehydrate the cells of the foodstuff, eliminating the hypotonic solution therefrom.
In the third step the product is placed in yet another receptacle which contains a rehydrating solution. Here, the foodstuff recovers ions it may have lost during preceding steps. This results in the foodstuff being restored, as nearly as possible, to its original, fresh or unpreserved form.
BACKGROUND OF THE INVENTION
My novel process may be used to preserve a great variety of proteic foodstuffs. One, commercially important application is the manufacture of fish meal for animal consumption.
Based, for example, on tests involving lamb breeding, the results obtained by feeding fish meal as heretofore prepared were definitely inferior to those expected based on the amount of nitrogen reported by previous tests of fish meal. This was due to the very low digestibility of such meal, to its high content of toxic amines, and to its high bacterial counts.
In reviewing the processes of manufacturing of fish meal heretofore employed, I found that the low digestibility is due to:
1. the fact that the making of the product involves dehydration by application of a direct flame in rotary furnace; or
2. that this is done at a very high temperature in a steam dehydrator (with the further disadvantage that the meal obtained by this process has a highly increased bacterial count); and
3. that meal obtained by the so-called "instant drying process" also suffers a very high thermal treatment which lowers digestibility.
Furthermore, in some heretofore employed processes, the foodstuff is polluted with exhaust gases from internal combustion engines, this being added to the pollutants already in the fish because of the state of decomposition or decay it normally has when it is manufactured into meal.
In an effort to overcome the disadvantages of the foodstuff preservation methods just described, a test was made in Teacapan, State of Sinaloa, Mexico of a modification of the Uruguayan system of fish siloing called "BIOPEZ" which, in turn, is a modification of the Swedish system designed by Virtanen. The tested process involves a bacterial promoted, hydrolysis or fermentation of fish, producing a paste which, while difficult to transport, can be delivered in tank trucks to distribution stations or to the consumer.
More specifically, the fish are ground and then transferred to cement vats. To each 100 kilograms of ground fish is added 20 kilograms of concentrated yeast (Cndomycetaceae subfamilia, Saecharomycetoideae genus, Saccaromyces isolated from the body of sea-bass (Micropogon opercularis)). The ingredients are intimately mixed, and the mixture is agitated three times a day for 6-7 days, after which fermentation is completed. The paste retains its original volume and has a dark brown color with a pleasant odor similar to that of dry figs and a firm consistency. To preserve the preparation for extended periods, 20 kilograms of 50% sulphuric acid are added to each 100 kilograms of paste giving a pH of 4.0-4.5. The paste may be directly fed to the animal without neutralizing it.
While an improvement over the other processes described above, the Mexican (modified Uruguayan) process just discussed is still not satisfactory as far as the quality of the product is concerned.
Another heretofore available technique for preserving protein foodstuffs is the process of "formol sprinkling" used in Peru. However, this only protects the product for a few hours, and it is generally inapplicable. Furthermore, the 37.2% by weight formaldehyde used in the process lowers the digestibility of proteins, increasing costs. Furthermore, formaldehyde acts superficially, not penetrating to the viscera of even small fish such as anchovies; and the amounts which are used are critical.
In short, to obtain adequate protein heretofore required the use of a fresh product; the only practical manner to achieve this to now has been to protect the material against decomposition by refrigeration. This may be done with ice as is done with shrimps and in the U.S. Gulf zone to manufacture fish meal or by using refrigerated brine as is done in Peru. Economically, neither of these two techniques is feasible for foodstuffs intended for consumption by animals.
OBJECTS OF THE INVENTION
It will be apparent to the reader from the foregoing that the primary object of the present invention resides in a novel, improved method of preserving proteic foodstuffs against decomposition.
Another object of the present invention is to provide a process for preserving fishes, crustaceans, mollusks, selachii, birds and mammals which allows them to be maintained at room temperature for long periods without decay.
Another object of the present invention is to provide a process for preserving proteic foodstuffs which minimizes changes in their proteins that would interfere with the digestibility of those constituents.
Still another of the objects of the present invention resides in providing a process for preserving foodstuffs which avoids the oxidation of fats, preventing deterioration and avoiding self-combustion during storage.
Other important objects, features, and advantages of the invention will be apparent to the reader from the preceding, from the appended claims, and from the ensuing detailed description of exemplary, preferred modes of carrying out its precepts.
DETAILED DESCRIPTION OF THE INVENTION
The process of preserving proteic foodstuffs described briefly above has been tested on many species of land and sea animals with good results. In the application of the process to the manufacture of fish meal, the protein was preserved in its initial condition; and bacterial counts were kept at less than 100 bacteria per gram during the whole process. Furthermore, the fats in the product were prevented from becoming rancid.
The meal, as preserved, had a digestibility of 98 percent and favorably passed biological toxicity tests; the amino acid composition was very similar to that of the meal obtained by the reduction and heat-transfer methods described in FOODSTUFFS, Jan. 18, 1969, pp. 44 and 45.
The processing costs were very low, and a study based thereon showed that a good recovery and profit could be obtained by selling the meal at prevailing market prices.
The tests which produced the foregoing results involved a great variety of marine species of all shapes and sizes. They could be preserved without evisceration, and a thick magma that could be readily processed into a meal was obtained.
In the tests carried out to "preserve" fish, the specimens generally maintained their shape.
As discussed above, my novel process for preserving proteic foodstuffs has a stabilization stage followed by a recovery stage.
In the first, stabilization stage, the animal or other proteic material is immersed in a liquid called a "stabilizer". This may be effected at room temperature with complete animals (even with viscera) or with portions of any size.
It is possible to protect the whole animal or just a part thereof; e.g., the meat, blood, viscera, etc. The time for which the foodstuff is immersed will vary according to the size of the animal, the nature of its skin, the temperature at which the process is carried out, the concentration in which the "stabilizing" liquid or "stabilizer" is used, etc.
After this first stage, the product can be handled and stored at room temperature. It is convenient to do so in bags (of polyethylene, for example) or in boxes or other packages which can be closed or sealed to avoid the dehydration of their contents. However, it is also possible to handle the product in bulk or in unsealed bags. In this case the product undergoes dessication but does not decay.
The second, revovery stage is also effected by immersion in liquid, in this case in three steps.
In the first step, the "protecting" or preservative effect of the stabilizing liquid is eliminated, and microorganisms present in the foodstuff are killed. In the second step, the product is washed; and, in the third step, the product is returned as nearly as possible to its initial condition; i.e., to the condition it enjoyed prior to immersion in the stabilizing liquid.
The first stage of this system is very simple. It only requires a vessel for the stabilizing liquid. The shape and size of the vessel may vary, but it is necessary that the product be totally immersed in the liquid for the entire time necessary to insure its protection. The stabilizing stage is preferably effected at a site where the foodstuff can be protected against the sun, dust, insects, and animals.
At the end of this first stage of the process, the product may stored at room temperature as indicated above. It is only necessary to allow for the outflow of excess liquid which will slowly come off of the product during storage.
If the product is to be handled in bulk or packaging which is not waterproof; it is preferably to accelerate this exudation of liquid so that the product can be transported in a dry dehydrated condition.
In the first, stabilizing stage of my process, use is made of the hydrogen ion to protect the proteins in the foodstuff being treated, advantage being taken of the inhibiting effect of such ions on enzymatic mechanisms which cause autolysis of cells. The hydrogen ions furnished by the donor also create a bacteriostatic and fungistatic environment, thus preventing microorganisms present in the foodstuff from attacking the proteic constituents thereof.
The component furnishing the hydrogen ions may be a potable organic acid such as acetic, citric, or lactic or an inorganic acid, preferably potable, such as hydrochloric or phosphoric. In any case the acid should be free of pollutants.
An enzyme is employed to break down the proteic intercellular cement between the cells of the material being treated especially those of the epithelal tissues. This permits the hydrogen ion furnishing component to penetrate rapidly into the material being treated.
The enzymes employed for my purposes are proteolytic; they may be of animal or vegetal origin, or they can be produced by different strains of bacterias or molds (fungi). Enzymes that I have successfully used are pepsin, papain, and bromelain.
The amount employed varies according to the activity of the enzyme. To guard against autolysis of the foodstuff cells, however, I employ the selected enzyme in a concentration which is approximately one tenth of that which would result in proteolytic activity. While the enzyme concentrations I employ thus do not result in breakdown of the cells, they are nevertheless capable of effecting the wanted dissolution of the intercellular cement.
Enzymatic action is insured by using a buffer to adjust the pH of the stabilizing liquid to a level ≦5 which is optinum for the particular enzyme being used. As a buffer I employ the same acid employed as the hydrogen ion donor or a salt of that acid.
Besides protecting the protein of the foodstuff being preserved, it is also necessary to inhibit decomposition of its fatty contituents. This is achieved in situ by adding a potable antioxidant to the stabilizing liquid. The amount of antioxidant is correlated to the amount of fat in the product so that the amount of antioxidant will not exceed the limits allowed for the use to which the product will be put.
Other processes for preserving foodstuffs which employ acidic materials are of course known. One example of such a process is pickling. A proteic product pickled with an organic acid at a pH lower than 4.5 may be preserved for long periods.
Another food preservation process employing an acid was developed by A. I. Virtamen for preserving green feed. This process, which involves the acidification of the product by one or more strong organic acids was used in Sweden in 1936 to preserve fish in an "ensiloed" condition at a pH of 2.
Another prior art process of the type in question was developed by Edin in Denmark in 1940 for making fish paste. In this process molasses, a yeast culture, and sulphuric acid are added to the raw material. This process works at a pH from 4 to 4.5.
Finally, Olsson (1940), Hanson and Lavern (1951), Petersen (1951), and Carl (1952) described a food preservation process in which use is made of mixtures of sulphuric acid plus hydrochloric acid, free sulphuric acid (i.e., free of arsenic), formic acid, sulphuric acid plus formic acid, and lactic acid plus molasses and a bacterial culture.
In all of the foregoing processes, the material being preserved must be milled, minced, shredded, or otherwise comminuted. This step with its cost, perhaps unwanted changes in the physical characteristics of the foodstuff, and other disadvantages are eliminated by my process.
The concept of treating proteic foodstuffs with a proteolytic enzyme is of course also not per se claimed to be novel. However, no one has herefore employed an enzyme in a food preservation process or, more particularly, to break down intercellular cement so that an acidic or alkaline material can penetrate through the foodstuff and create an environment which inhibits reactions that would cause decay of the foodstuff.
For example, Ramsbottom et al U.S. Pat. No. 2,321,623 and Schack et al U.S. Pat. No. 3,533,803, both cited in parent application Ser. No. 785,679, are not concerned with preserving proteic foodstuffs but with tenderizing "the flesh of edible animal carcasses" by using enzymes. The Rutman (U.S. Pat. No. 3,561,973) and Brocklesby (U.S. Pat. No. 2,934,433) patents cited in that application are equally remote. The first is concerned with a method for digesting a mixture of pulped fish and fat, the second with a high temperature process for peptizing insoluble proteins.
As mentioned above, the product being preserved is immersed seriatim in three different liquids in the second, recovery stage of the process. The objective of the first step is to rapidly change the pH of the product. This, which is done by immersing the product in an alkaline solution and which I term the "ionic blow", produces a beneficial bactericidal and fungicidal effect.
The pH adjustment is facilitated by two characteristics of the stabilized product. First, the opening of the intercellular spaces allows the recovery liquid to penetrate to the interior of the product, insuring a rapid and adequate concentration of the hydroxyl ion in all cells of the product.
Second, the cells are dehydrated when they are submitted to the stabilizing solution as the latter is hypertonic. This dehydrated condition speeds penetration of the hydroxyl ions into the cells as the first recovery solution is hypotonic.
The bactericidal effect is obtained because most bacterial strains commonly found on the skin and mucous membrane of animals and in the contents of the intestinal tract are active only at a pH which is neutral, slightly acid, or slightly alkaline. When they are subjected to a sudden and large change in pH, first toward acidity and then toward alkalinity, or vice versa; i.e., to an ionic blow, they do not survive.
The same is true of fungi found in the environments just described.
The hypotonic alkaline solution employed to deliver the ionic blow is prepared by dissolving a potable base in water in an amount sufficient to produce a pH ≧9. Suitable bases include sodium, potassium, and calcium hydroxides and mixtures of the foregoing.
This and the subsequent steps of the recovery stage should be performed under sterile conditions. Once the protective effect of the stabilizing liquid has been taken away by immersing the product in the alkaline solution, the product becomes highly susceptible to pollution by bacteria or fungi. If one carries out the second stage steps under strict aseptic conditions, the final product may be kept at room temperature in hermetically sealed, sterilized packages. If the conditions are not sufficiently aseptic, it is necessary to refrigerate the reconstituted product to avoid decay.
The previously mentioned second step of the recovery stage involves the immersion of the foodstuff in a hypertonic solution having a pH of 5 to 7 in order to adjust the pH of the foodstuff to the desired level. Because of the previous breakdown of the intercellular cement this step also proceeds rapidly and efficiently. In addition, because of the lower osmotic pressure of the solution used to produce the ionic blow in the preceding step, that solution is efficiently expelled from the foodstuff cells by the hypertonic solution used in the second step.
The hypertonic solution can be prepared by dissolving any of a wide variety of potatable salts evident to the average chemist in water. Sodium chloride will typically be employed because of its low cost and widespread availability.
In the first and second steps of the recovery stage the ionic concentration in the foodstuff is altered by the osmotic pressure-induced passage of ions through the semi-permeable walls of the foodstuff cells. The electrolytic balance is restored and the fluid content of the foodstuff adjusted to the wanted level in the third step of the recovery stage, again by immersing the foodstuff in an appropriate solution.
The composition of the rehydrating solution employed in the third step will depend upon, and can readily be determined for, the particular foodstuff involved. One exemplary composition is defined hereinafter.
Preferred modes of carrying out my novel process are described in the examples wich follow.
EXAMPLE 1
To stabilize 100 kg. of sardine with an approximate content of 14 percent of fat, the following constituents were employed.
hydrochloric acid (30 percent), free of contaminants: 10 liters
potassium chloride: 7.9 grams
purified pepsin 1/10,000 (Difco): 1 gram
Ionol 2,6-di-tert-butyl 4-methyl phenol antioxidant (Shell): 1 gram
drinking water: 88 liters
A buffer solution (Solution A) was prepared by adding the potassium chloride dissolved in one liter of water to 88 liters of water. Thereafter the hydrochloric acid was added with continual stirring (a long stem funnel or a hose is used to add the acid under the surface and avoid the generation of toxic vapors).
The pepsin was dissolved in 400 ml of water, and the Ionol was added. This solution, called "Solution B", was mixed with Solution A; and the mixture was briefly homogenized before immersing the sardines in it to stabilize them.
The stabilized sardines were placed in perforated plastic boxes or nets to facilitate handling and immersed (in a tank) in a hypotonic solution made by diluting 14 liters of a 10 N sodium hydroxide solution (NaOh 10/N) in 86 liters of drinking water. The liquid was agitated to accelerate the alkalinization process.
The sardines were removed from the hypotonic solution, and excess fluid was allowed to drain off. Then the sardines were placed in another washing tank containing a hypertonic solution of sodium chloride to dehydrate the cells, thus accelerating the outflow of the hydroxyl ions. This solution was prepared by dissolving 12 grams of sodium chloride per liter in a large quantity of water.
The product was introduced into a third tank containing a rehydrating solution from which the product recovered ions lost in the previous steps. This solution contained:
______________________________________ Grams/literIon of water______________________________________Na.sup.+ 3220K.sup.+ 390Ca.sup.++ 100.2Mg.sup.++ 36.5Cl.sup.- 3660Perfect Osmolarity 306 m mol/liter______________________________________
EXAMPLE 2
100 kilograms of anchovies were stabilized using the procedure of Example 1 except that sea water was used instead of drinking water. The anchovies were then converted to a meal.
EXAMPLE 3
100 kilograms of shrimp were treated as described in Example 1. Both the stabilizing and recovery stages were employed.
The products identified in Examples 2 and 3 were tested for proteic efficiency and subchronic toxicity and subjected to microbiological and proximate analyses.
Proteic efficiency was evaluated using the protocol for measuring protein efficiency ratio (PER) promulgated by the assessor's group for proteins of the FAO (Food and Agricultural Organization, an agency of the United Nations).
The growth of animals used for testing the shrimp was superior to the growth of animals fed with the protein of reference (casein) by a ratio of 1.91:1.
The PER value obtained for casein was 2.51, and for the protein of the shrimps it was 2.78. This demonstrated the efficiency of the protein studied.
Sub-chronic toxicity tests were made on groups of 10 male rats and 10 females rats at two ingestion levels of the test product (shrimp of Example 3). The test period lasted 90 days. Besides recording and analyzing food ingestion and growth, hemoglobin behavior was investigated; and biochemical data were obtained for blood and urine during the last week of the test. The study was completed by macroscopically examining all the animals via post mortem examination. From eight to ten organs were weighed. Tissue samples (20 to 30) were incorporated in paraffin and examined microscopically. The microscopical examination was restricted to the samples obtained from the animals that were fed with the larger quantities of the test products.
Pathological examinations of organs such as the spleen, suprarenal gland and others showed them to be normal. The studies of haematic citology and blood chemistry gave values which are within normal limits.
In short, the shrimps processed as described in Example 3 were found to be non-toxic and usable for human consumption.
The results of the microbiological analyses of products described in Examples 2 and 3 were as follows:
TABLE I______________________________________Microbiological Analysis of Fresh Anchovy (Control)and Anchovy Meals Treated by Different Methods ofPreservationL O T Commercial Product of Control Process Example 2______________________________________Total countof colonies/g 12,900 230 not presentColiformNMP/g 4 not present not presentFungi count,colonies/g 30 not present not present______________________________________ NMP: Most probable number of colonies per gram Commercial Process: Peruvian method (formaldehyde and sodium nitrite, see prior discussion "Background etc."-
TABLE 2______________________________________Maximum Values in The Microbiological Control ofShrimps Preserved With The Preservation System ofEnzymatic Inhibition Shrimp of Control Example 3______________________________________Standard count of mesophillicorganisms - colonies/ml 2,200 0Standard count of coliformorganisms - NMP/ml 15 0Enterococcoes - colonies/ml 0 0Molds (Fungi) and yeastscolonies/ml 0 0______________________________________ Control: Shrimps frozen in natural state with heads conserved
The following table contains data gathered from proximate analyses of anchovy meal prepared as described in Example 2, anchovies treated with a commercial additive and converted into meal, and a control.
TABLE 3______________________________________Proximate Analyses of Fresh Anchovy (Control) andAnchovy Meal Treated by Different ProcessL O T Commercial Process of Control Process Example 2______________________________________Moisture 72.8 22.6 29.1Proteins BH 18.3 51.0 46.1(N × 6.25) BS 67.3 65.9 65.0Etherous BH 5.4 15.7 16.9Extract BS 19.9 20.3 23.8Ash BH 3.4 10.2 4.5 BS 12.5 13.2 6.4Non nitro- BH 0.1 0.5 3.4genized BS 0.3 0.6 4.8extract______________________________________ BH: Wet base BS: Dry base Commercial Process: same as identified in Table 1
To this point, my process for preserving proteic foods has been described primarily with reference to the use of an acidic buffering solution and hydrogen ions to protect the cells of the animal and inhibit activity of the accompanying microorganisms. However, as indicated above, the hydroxyl ion may also be employed for the same purpose. In that case I use a proteolytic enzyme which is active in an alkaline environment (pH≧9) and an alkaline buffer solution which is adjusted to the optimal pH for the selected enzyme. The remainder of the stabilizing stage remains the same.
Various materials may be employed to prepared alkaline buffers of the desired pH and to furnish the hydroxyl ions. These include sodium, potassium, and calcium hydroxides and combinations of those compounds.
In the second, recovery stage only the first step is changed and that only to the extent that an acid, rather than alkaline, hypotonic solution is used to produce the ionic blow. Those compounds which are used in the acidic buffer solutions can equally well be employed in the acidic hypotonic solutions.
With the exceptions identified above, the process using an alkaline buffer solution can be carried out essentially as described in Example 1.
The stabilization stage of my process can also be applied to whole animals to produce natural teaching models. These, among other advantages, do not have to be refrigerated. Also, the consistencies of the tissues remain similar to those of the unpreserved animal, and the preserved animals are not dangerous to handle.
The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description; and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | A method for protecting animal derived foodstuffs against spoilage which does not require refrigeration. The foodstuff is immersed in a stabilizer composed of a buffer solution, a proteolytic enzyme, and an antioxidant following which it may be stored at room temperature. The foodstuff can be reconstituted by rapidly reversing its pH by immersion in a hypotonic solution to kill bacteria present in the foodstuffs and then first immersing it in a hypertonic solution to eliminate the hypotonic solution and then rehydrating it. Alternatively, the foodstuff may be utilized, typically as an animal food and in meal form, without reconstituting it. | 0 |
RELATED APPLICATIONS
There are no current co-pending applications.
FIELD OF THE INVENTION
The presently disclosed subject matter is directed toward multi-player games. More particularly it is directed to a miniaturized, multiple player hockey game suitable for indoor and outdoor use.
BACKGROUND OF THE INVENTION
Hockey is one (1) of the fastest growing sports in the United States. While traditionally hockey was a winter sport only played in colder regions, one can now find hockey leagues in the spring, summer, and fall all across the United States. Fast, exciting, and fun, hockey can be, and is, played by the very young to the very old. From junior leagues to international teams, millions of Americans simply love hockey.
Hockey is a game usually associated with ice. Unfortunately this greatly reduces the possibility for many people to enjoy hockey. In addition to those without access to a hockey rink there are those who are out of shape, perhaps elderly or disabled, who have a different skill level than other players, or who for a variety of other reasons are not able to enjoy the physical aspects of hockey as played on ice.
Accordingly, there exists a need for a means by which the fun, competition, and thrills associated with the game of hockey can be enjoyed by all, regardless of access to a hockey rink. Beneficially such a means would enable multiple people to compete in a challenging environment. Preferably such a means would be easy to use, low in cost, simulate hockey play, could be used both indoors and outdoors, and would not require too much space.
SUMMARY OF THE INVENTION
The principles of the present invention provide for a multi-player hockey game that seeks to make the fun, competition, and thrills associated with the game of hockey accessible to those without access to a hockey rink. Beneficially the multi-player hockey game enables multiple people to compete in simulated hockey. The multi-player hockey game can be easily used indoors or out in a limited playing area and can be made available at low cost.
A hockey game that is in accord with the present invention includes a floor structure having a flat playing surface with a perimeter and a wall structure extending along that perimeter. The wall structure includes a first long wall, a first end wall, a second long wall, a second end wall, and a dividing wall that extends between the middle of the first long wall and the middle of the second long wall. The first long wall, first end wall, second long wall, and second end wall are rounded at their corners. The hockey game further includes a faceoff platform on top of the dividing wall. The first end wall has a half-oval-shaped first scoring aperture, the second end wall has a half-oval-shaped second scoring aperture; and the dividing wall includes two half-oval-shaped center apertures.
Beneficially the two (2) center apertures have the same dimensions as the first scoring aperture, while the second scoring aperture has the same dimensions as the first scoring aperture.
In practice the playing surface is comprised of a low-friction smooth plastic, faceoff platform is centered on the dividing wall and the wall structure is approximately six inches (6 in.) high. The hockey game may further include puck and at least two (2) hockey sticks. Beneficially the playing surface is approximately eight feet (8 ft.) long and three feet (3 ft.) wide. Also beneficially the hockey game includes indicia.
Preferably the wall structure is removable from the floor structure. The floor structure may include a recessed channel-shaped first wall slot and a recessed channel-shaped second wall slot and the first wall slot may receive the bottom edge of the first long wall while the second end wall receives the bottom edge of the second long wall. The first wall slot and the second wall slot may receive different ends of the first end wall. The floor structure may also include a recessed channel-shaped third wall slot, a recessed channel-shaped fourth wall slot, and a recessed channel-shaped fifth wall slot and the third wall slot, floor structure fourth wall slot, and floor structure fifth wall slot may receive bottom edges of floor structure dividing wall.
Another hockey game that is in accord with the present invention includes a floor structure having a flat playing surface with an outer perimeter. The floor structure has a recessed channel-shaped first wall slot disposed around part of the perimeter, a recessed channel-shaped second wall slot disposed around another part of the perimeter, a recessed channel-shaped third wall slot extending inward from the middle of the first wall slot, a recessed channel-shaped fourth wall slot extending inward from the middle of the second wall slot, and a recessed channel-shaped fifth wall slot disposed in line between the third wall slot and the fourth wall slot. The hockey game further includes a wall structure having a first long wall and a first end wall with bottom edges that are inserted into the first wall slot, a second long wall and a second end wall with bottom edges inserted into the second wall slot, and a dividing wall having bottom edges inserted into the third wall slot, into the fourth wall slot, and the fifth wall slot. In addition there is a faceoff platform on top of the dividing wall. The first long wall, the first end wall, the second long wall, and the second end wall have rounded corners. In addition, the first end wall has a half-oval-shaped first scoring aperture, the second end wall has a half-oval-shaped second scoring aperture, and the dividing wall includes two (2) half-oval-shaped center apertures.
In practice the two (2) center apertures have the same dimensions as the first scoring aperture, and the second scoring aperture has the same dimensions as the first scoring aperture. In addition, the playing surface is beneficially comprised of a low-friction smooth plastic and the faceoff platform is beneficially centered on the dividing wall. The hockey game may further include a puck and at least two (2) hockey sticks.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:
FIG. 1 is a perspective view of a hockey game 10 that is in accord with a preferred embodiment of the present invention;
FIG. 2 is an environmental view of an in-use hockey game;
FIG. 3 a is an exploded view of the hockey game 10 shown in FIGS. 1 and 2 ;
FIG. 3 b is a section view of the hockey game 10 taken along section line A-A of FIG. 2 ; and,
FIG. 3 c is a section view of the hockey game 10 taken along section line B-B of FIG. 2 .
DESCRIPTIVE KEY
10 hockey game
20 wall structure
22 long perimeter wall
24 end perimeter wall
25 divider wall
26 scoring aperture
27 faceoff platform
28 center aperture
40 lower floor structure
42 playing surface
43 horizontal edge
44 a first side wall slot
44 b second side wall slot
44 c third wall slot
44 d fourth wall slot
44 e fifth wall slot
50 hockey stick
52 grip
60 puck
70 indicia
100 player
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within FIGS. 1 through 3 c . However, the invention is not limited to the described embodiment, and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention and that any such work around will also fall under scope of this invention. It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.
The present invention describes a hockey game that includes a miniature hockey rink and a predetermined method of play. While described herein as being played indoors, that is for convenience of explanation only. The hockey game 10 is well suited for both indoor and outdoor play.
FIG. 1 presents a perspective view of a hockey game 10 that is in accord with a preferred embodiment of the present invention. The hockey game 10 includes a lower floor structure 40 having a flat plastic playing surface 42 that is approximately eight feet (8 ft.) long and three feet (3 ft.) wide. Those dimensions are very well suited for the majority of players and are usually highly beneficial and represent a scaled down hockey rink. However other dimensions maybe used with younger players or players with disabilities. As shown, the hockey game 10 includes the lower floor structure 40 and an upper wall structure 20 that is comprised of long perimeter walls 22 , end perimeter walls 24 , and a bisecting dividing wall 25 . The lower floor structure 40 and the upper wall structure 20 resemble a miniature hockey rink.
Referring now to FIGS. 1 and 2 , the hockey game 10 also includes a puck 60 and sufficient hockey sticks 50 to allow up to four (4) players to play the hockey game 10 . The long perimeter walls 22 , the end perimeter walls 24 , and the dividing wall 25 are beneficially about six inches (6 in.) high. The long perimeter walls 22 and the end perimeter walls 24 are rounded at the corners while the bisecting dividing wall 25 extends between the centers of the long perimeter walls 22 .
Still referring to FIGS. 1 and 2 , the end perimeter walls 24 each have a half-oval-shaped scoring aperture 26 that is approximately three to four inches (3-4 in.) wide. Each scoring aperture 26 represents an opponent's goal. Centered on top of the dividing wall 25 is a faceoff platform 27 . About half way between the center of the faceoff platform 27 and each long perimeter walls 22 is a center aperture 28 . Thus there are two center apertures. During play a player 100 (see FIG. 2 ) attempts to manipulate a puck 60 using a hockey stick 50 through one of the center apertures 28 and then into an opponent's scoring aperture 26 . Each center aperture 28 is shaped similarly to the scoring apertures 26 .
The outer surfaces of the long perimeter walls 22 and the end perimeter walls 24 , as well as the playing surface 42 may include various indicia 70 such as scripts or logos or images to customize and personalize the hockey game 10 . For example, the indicia 70 may include sports names/logos, personal names, symbols, lines, pictures, and the like, in various colors and patterns. Such indicia 70 may seek to align the hockey game 10 with professional or college teams, their colors, or sponsors.
The lower floor structure 40 is beneficially a flat plastic panel having a perimeter shape that is similar to but slightly larger than the perimeter formed by the long perimeter walls 22 and the end perimeter walls 24 . The extra dimensions of the lower floor structure 40 provide a horizontal edge 43 . Significantly, the lower floor structure 40 may be removed, if desired, to enable use of the upper wall structure 20 on an existing surface. The lower floor structure 40 includes the playing surface 42 , which is beneficially a low-friction surface that enables smooth sliding of a puck 60 during play.
Referring now to FIGS. 1 , 2 , 3 a , and 3 b , the lower floor structure 40 includes a recessed channel-shaped first wall slot 44 a and recessed channel-shaped second wall slot 44 b which are disposed around opposing perimeter edges of the lower floor structure 40 . The first wall slot 44 a and the second wall slot 44 b are configured to receive the bottom edges of the aforementioned long perimeter walls 22 and the end perimeter walls 24 . The first wall slot 44 a and the second wall slot 44 b are separated at the ends by the positions of the scoring apertures 26 . The first wall slot 44 a and the second wall slot 44 b are envisioned as being approximately one-quarter of an inch (¼ in.) deep and sized to receive, anchor and stabilize the long perimeter walls 22 and the end perimeter walls 24 .
Referring now to FIGS. 1 , 2 , 3 a , and 3 c , the lower floor structure 40 also includes a recessed third wall slot 44 c , a recessed fourth wall slot 44 d , and a recessed fifth wall slot 44 e . The third wall slot 44 c , fourth wall slot 44 d , and fifth wall slot 44 e are disposed along a line that bi-sects the lower floor structure 40 between the long perimeter walls 22 . The fourth wall slot 44 d extends perpendicularly inward from the second wall slot 44 b , while the fifth wall slot 44 e extends perpendicularly inward from the first wall slot 44 a . The third wall slot 44 c , fourth wall slot 44 d , and fifth wall slot 44 e are configured to receive the bottom edges of the aforementioned dividing wall 25 . Like the first wall slot 44 a and second wall slot 44 b , the third wall slot 44 c , fourth wall slot 44 d , and fifth wall slot 44 e are envisioned as being approximately one-quarter of an inch (¼ in.) deep and sized to receive, anchor and stabilize the dividing wall 25 .
Referring now to FIGS. 1 and 2 , the hockey game 10 preferably comes with at least two (2) plastic pucks 60 and at least four (4) hockey sticks 50 . This enables up to four (4) players to play the hockey game 10 . However, the hockey game 10 may include more hockey sticks 50 and pucks 60 as required to enable more players 100 to play. Each hockey stick 50 includes a sprayed on or adhesively bonded grip 52 comprised of foam rubber or another high-friction material which is located at the end of the long leg of the hockey stick 50 . The hockey game 10 , as well as the hockey sticks 50 and pucks 60 are envisioned as being introduced in both full-sized and scaled-down versions based upon particular age groups of the players 100 .
FIG. 2 shows the hockey game 10 in-use by two (2) players 100 . However, as previously mentioned it is envisioned that sufficient equipment is available for up to four (4) players 100 to play the hockey game 10 . The players 100 are envisioned as standing along the outside of the upper wall structure 20 and manipulating a puck 60 along the playing surface 42 using their hockey sticks 50 . Scoring is accomplished by causing the puck 60 to pass through the scoring aperture 26 at their opponent's end wall.
It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. After initial purchase or acquisition of the hockey game 10 , it would be installed and utilized as indicated in FIG. 2 .
The method of installing and utilizing the hockey game 10 may be achieved by performing the following steps: procuring a model of the hockey game 10 having a desired overall size which corresponds to an age-range of intended players 100 , as well as various desired external and internal indicia 70 ; selecting teams of players 100 ; positioning up to four (4) players 100 outside the long perimeter walls 22 and the end perimeter walls 24 ; starting the hockey game 10 by “facing-off” the puck 60 by placing the puck 60 up the central faceoff platform 27 ; tapping all of the player's hockey sticks 50 a pre-determined number of times in a synchronous manner to begin play; moving the puck 60 using the hockey sticks 50 along the playing surface 42 and through one of the center apertures 28 , if necessary; propelling the puck 60 through an opposing team's scoring aperture 26 to score a point; continuing to “face-off” the puck 60 and score points by repeating the above steps and following the general rules of a conventional hockey game until a team of players 100 obtains five (5) points; switching the players 100 from end-to-end of the hockey game 10 ; ending the hockey game 10 by continuing the playing and scoring sequence until a team of players 100 obtains a total of ten (10) points; starting another hockey game 10 by selecting different teams for subsequent play or playing additional games with the same teams as desired; and, enjoying a hockey-like game in an indoor environment afforded users of the present invention 10 .
The method of utilizing the hockey game 10 in an outdoor environment may be achieved by performing the following steps: removing the upper wall structure 20 from the lower floor structure 40 and placing the upper wall structure 20 upon a suitable existing paved surface; and, playing the hockey game 10 as previously described.
The use of the hockey game 10 provides the ability for hockey lovers of all ages and physical abilities to enjoy the action of the sport, regardless of their ability to access a conventional hockey rink.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions or substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention. | A miniaturized hockey game having a wall structure and a floor structure configured to represent a hockey rink along with hockey sticks and a puck. The wall structure is removable from the floor structure. To that end the floor structure include recessed grooves for receiving and supporting the wall structure. A faceoff platform is on top of a dividing wall of the wall structure. The wall structure includes scoring apertures for simulating nets and center apertures for providing obstacles to increase the difficulty of play. In use players stand along the perimeter of the hockey game and manipulate a puck using their hockey sticks to cause the puck to pass through the scoring apertures to score points. | 0 |
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